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Sample records for anthers

  1. Choreography of anthers

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Choreography of anthers. They open upwards initially. Turn around one after another. Presumably to make sure there is no self-pollination. Space below the anthers adequate for a honey bee or a bumble bee to get in and get out. Pollens can be transferred while flying out!

  2. Analysis of Anther Cell Differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Hong [Pennsylvania State Univ., University Park, PA (United States)

    2015-01-19

    This grant supports research on genes that regulate Arabidopsis anther development. The proposed research largely concerns that functions of two key regulatory genes: SPL and DYT1, which encode two putative transcription factors, as well as genes that interact with these genes. Last year, we reported progress in preparation for ChIP analysis with SPL and DYT1, in dyt1 and ams microarray experiments and initial data analysis, in functional analysis of one of the DYT1 target gene, MYB35.

  3. Identification of anther-specific/predominant genes regulated by gibberellin during development of lily anthers.

    Science.gov (United States)

    Hsu, Yi-Feng; Tzeng, Jhih-Deng; Liu, Ming-Che; Yei, Fung-Ling; Chung, Mei-Chu; Wang, Co-Shine

    2008-01-01

    We successfully identify anther-specific/predominant genes induced by gibberellin (GA) at the microspore stage of lily (Lilium longiflorum) anthers. We used a suppression-subtractive hybridization strategy to identify 22 individual cDNAs followed by a reverse RNA dot plot to determine their specificities at the microspore stage. Of the 22 genes, 12 are clearly anther-specific and three are anther-predominant. Sequence analysis revealed that five anther-specific/predominant genes are novel. The transcripts of anther-specific/predominant genes were differentially detected at the microspore development phase; some began accumulating in level as early as the occurrence of meiosis. When uniconazole, an inhibitor of GA biosynthesis was applied in young lily plants we found that all of the anther-specific/predominant genes, with the exception of LLA-139, were up-regulated by GAs in the anther while only some were responsive to the exogenous addition of 100 microM GA3. In situ hybridization with antisense riboprobes of selected genes in the anther showed a strong signal localized to the tapetal layer. The different actions of GA on gene expression in anthers are discussed.

  4. Anther development stage and gamma radiation effects on tomato anther-derived callus formation

    International Nuclear Information System (INIS)

    Brasileiro, Ana Christina R.; Willadino, Lilia; Guerra, Marcelo; Colaco, Waldeciro; Meunier, Isabelle; Camara, Terezinha R.

    1999-01-01

    Two experiments were carried (I) to determine tomato anther development stage influence on callus production; and (II) to investigate gamma radiation effects on anther culture. In the first experiment, anthers of a tomato hybrid (IPA 5 x Rotam 4-F 1 ) were grown on three media. Although calli were induced at all stages of anther development, varying from prophase I to mono nucleate microspore, callus frequency decreased as anther development progressed and calli induction were not significantly affected by all media tested. Anthers containing prophase I meiocytes produced the highest calli frequency. Anther and flower bud length both were significantly correlated with anther development stage. In the second experiment, seed and floral buds of tomato hybrids IPA 5 x Rotam 4 (F 2 ), IPA 6 x Rotam 4 (F 2 ) and IPA 8 x 217.1 (F 2 ) were submitted to gamma-ray and anthers were plated on two media described by Gresshoff and Doy (1972) supplemented with 2.0 mg L -1 NAA + 5.0 mg L -1 KIN and 2.0 mg L -1 NAA + 1.0 mg L -1 KIN. No significant differences for genotype and dosage testes were found for calli formation. (author)

  5. Induction of microspore-derived embryos by anther culture in ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-28

    Nov 28, 2011 ... obtained from A269, one of the genotypes tolerant to low temperature. The anthers cultured from April to May, gave the ... microspores in each anther and numerous haploid plants can be obtained from a single anther. ... in Turkey can be observed in several regions in both open fields and greenhouses.

  6. Biochemical Changes during Development Process of Anther ...

    African Journals Online (AJOL)

    ERCAN

    2012-02-20

    Feb 20, 2012 ... The measurement of starch contents was referred to the iodine staining ... The soluble sugar and starch contents of anther-derived embryos in loquat at different developmental stages. ... Means having the same letter in the columns are not significantly different according to Duncan's multiple range test.

  7. Biochemical Changes during Development Process of Anther ...

    African Journals Online (AJOL)

    ERCAN

    2012-02-20

    Feb 20, 2012 ... The main metabolic substances changes during the development process of anther-derived embryos in loquat (Eriobotrya japonica Lindl. ... provide energy for the new development phase (Zang et al., 2004; He and Qi, 2002). ... were used for experimental materials (Figure 1) such as embryogenic calluses ...

  8. Anther culture studies in W. Murcott mandarin genotype

    Directory of Open Access Journals (Sweden)

    Yıldız AKA KAÇAR

    2014-12-01

    Full Text Available Obtaining haploid plants is one of the important tool that shorten the plant breeding process. Anther culture is one of the method used for obtaining haploid plants. Anther culture studies are carried out for several plant species. In the present study, flowers at different sizes of W. Murcott mandarin were collected at the blooming period. Stage of mononuclear microspore of anthers was determined according to method of acetocarmine. Mononuclear microspore stage of anthers was observed in flowers 4-5 mm in diameter. Anther culture experiments were carried out with 4-5 mm in diameter anthers. In this study, temperature pre-treatment was performed at 4˚C and 25˚C for two days. Surface sterilization was performed in flowers and anthers were cultured in nutrient medium N6. Anther culture assays were performed with the three different concentrations of TDZ (0 mg l-1 TDZ, 0.1 mg l-1 TDZ, 0.5 mg l-1 TDZ. Half of anthers were cultured in dark condition while the other half in 16 hours light, 8 hours dark climate room conditions. Anthers containing mononuclear microspore stage were cultured and, changes occurring in the anther explants were discussed in the article.

  9. Anther Wall Formation in Solanaceae Species

    Science.gov (United States)

    CARRIZO GARCÍA, CAROLINA

    2002-01-01

    Anther wall formation was studied in 32 species belonging to 27 genera of Solanaceae. Dicotyledonous and basic types of wall formation were observed, as well as several deviations due to subsequent periclinal divisions in the layers formed (middle layers and sometimes the endothecium). One type of wall formation was observed in each species. Some genera are uniform in their type of wall formation, while others are heterogeneous; a similar situation was observed at the tribal level. Summarizing all reported information on anther wall formation in the Solanaceae, 64 % of species show the basic type, while the remaining 36 % show the dicotyledonous type. Thus, neither type predominates, and no single type characterizes genera, tribes or the entire family. PMID:12451025

  10. Chloroplasts in anther endothecium of Zea mays (Poaceae).

    Science.gov (United States)

    Murphy, Katherine M; Egger, Rachel L; Walbot, Virginia

    2015-11-01

    Although anthers of Zea mays, Oryza sativa, and Arabidopsis thaliana have been studied intensively using genetic and biochemical analyses in the past 20 years, few updates to anther anatomical and ultrastructural descriptions have been reported. For example, no transmission electron microscopy (TEM) images of the premeiotic maize anther have been published. Here we report the presence of chloroplasts in maize anthers. TEM imaging, electron acceptor photosynthesis assay, in planta photon detection, microarray analysis, and light and fluorescence microscopy were used to investigate the presence of chloroplasts in the maize anther. Most cells of the maize subepidermal endothecium have starch-containing chloroplasts that do not conduct measurable photosynthesis in vitro. The maize anther contains chloroplasts in most subepidermal, endothecial cells. Although maize anthers receive sufficient light to photosynthesize in vivo and the maize anther transcribes >96% of photosynthesis-associated genes found in the maize leaf, no photosynthetic light reaction activity was detected in vitro. The endothecial cell layer should no longer be defined as a complete circle viewed transversely in anther lobes, because chloroplasts are observed only in cells directly beneath the epidermis and not those adjacent to the connective tissue. We propose that chloroplasts be a defining characteristic of differentiated endothecial cells and that nonsubepidermal endothecial cells that lack chloroplasts be defined as a separate cell type, the interendothecium. © 2015 Botanical Society of America.

  11. Dynamic changes of main metabolic substances during anther ...

    African Journals Online (AJOL)

    The main metabolic substances changes during the development process of anther-derived embryos in loquat (Eriobotrya japonica Lindl. cv. 'Dawuxing') were studied. These include water contents, dry mass contents, carbohydrates, soluble proteins and nucleic acids. In the developmental stages of anther-derived ...

  12. Diallel analysis of anther culture response in wheat ( Triticum ...

    African Journals Online (AJOL)

    The four wheat (Triticum aestivum L.) genotypes differing in their ability to produce embryogenic callus from anther culture were reciprocally crossed and inheritance of anther culture response [callus induction frequency (CIF, %), embryogenic callus induction frequency (ECIF, %), regeneration capacity of callus (RCC, %) ...

  13. Anther development in tribe Epidendreae: orchids with contrasting pollination syndromes

    Directory of Open Access Journals (Sweden)

    Benjamín Valencia-Nieto

    2018-02-01

    Full Text Available Background Epidendreae is one of the most diverse tribes among the orchids with remarkable variation in life form, floral morphology and pollination syndromes. Its circumscription was recently revised and subtribes Agrostophyllinae and Calypsoinae were transferred into this tribe. One of the principal floral characters utilized in classification of orchids is the incumbency or bending of the column. This study records and compares late stages of anther, column and lip development, and discusses anther characters in fifteen representative taxa of five of the six subtribes in Epidendreae with respect to classification and pollination biology. Methods A series of late floral stages were sampled and fixed for examination under scanning electron microscope. Results Anther incumbency or bending in this group varies from 90° to almost 180°. Incumbency in the late stages of development is reached in Bletiinae, Ponerinae, Pleurothallidinae and Laeliinae whereas incumbency is reached early in its development in Corallorhiza and Govenia of Calypsoinae. Discussion Our observations indicate that the position of Chysis in subtribe Bletiinae needs revision based on differences in a number floral, and in particular of anther characters; and that Coelia only shares the early anther incumbency with Calypsoinae members, but not the rest of floral and anther characters. Anatomical characters such as crystals around the actinocytic stomata on the anther cap and sugar crystals in Laeliinae; lack of rostellum in Bletiinae; coalescent anther with the column, lack of trichomes and papillae on lip keels, and underdeveloped rostellum in Chysis; a mechanism by which the anther cap comes off (it is joined with the grooved lip by a claw in Isochilus are all related to pollination syndromes and reproductive biology.

  14. Embryogenic callus induction and regeneration in anther culture of ...

    African Journals Online (AJOL)

    . Initially, two experiments were conducted to identify the appropriate morphological stage of capitula (buds) for harvesting maximum number of responsive anthers and to study the optimum cold pretreatment duration for callus induction from ...

  15. Ethylene regulates the timing of anther dehiscence in tobacco.

    Science.gov (United States)

    Rieu, I; Wolters-Arts, M; Derksen, J; Mariani, C; Weterings, K

    2003-05-01

    We investigated the involvement of ethylene signaling in the development of the reproductive structures in tobacco ( Nicotiana tabacum L.) by studying flowers that were insensitive to ethylene. Ethylene-insensitivity was generated either by expression of the mutant etr1-1 ethylene-receptor allele from Arabidopsis thaliana or by treatment with the ethylene-perception inhibitor 1-methylcyclopropene (MCP). Development of ovaries and ovules was unaffected by ethylene-insensitivity. Anther development was also unaffected, but the final event of dehiscence was delayed and was no longer synchronous with flower opening. We showed that in these anthers degeneration of the stomium cells and dehydration were delayed. In addition, we found that MCP-treatment of detached flowers and isolated, almost mature anthers delayed dehiscence whereas ethylene-treatment accelerated dehiscence. This indicated that ethylene has a direct effect on a process that takes place in the anthers just before dehiscence. Because a similar function has been described for jasmonic acid in Arabidopsis, we suggest that ethylene acts similarly to or perhaps even in concurrence with jasmonic acid as a signaling molecule controlling the processes that lead to anther dehiscence in tobacco.

  16. Organelles genome stability of wheat plantlets produced by anther ...

    African Journals Online (AJOL)

    Yomi

    2012-03-15

    Mar 15, 2012 ... Key words: RFLP analysis, wheat plantlets, wheat anther culture, doubled haploids, genetic stability, mitochondria and chloroplast genome. INTRODUCTION. Wheat (Triticum aestivum L.) is one of the most important staple food crops of the family Poaceae. Among the food crops, wheat is a common source ...

  17. Establishment of plant regeneration system from anther culture of ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-28

    Nov 28, 2011 ... system can be applied for both genetic transformation and doubled haploid plant induction. Key words: Tagetes ... ornamental plant and has strong adaptability to adverse environments as it ... Table 1. Effect of genotypes on callus induction and shoot regeneration from anthers of Tagetes patula. Genotype.

  18. Comparison of anther and microspore culture in androgenic ...

    African Journals Online (AJOL)

    The aim of this study was to compare the efficiency of broccoli anther and microspore culture methods for doubled haploid (DH) lines production. We evaluated the main influencing factors and optimized the culture methods to improve embryo induction and plant regeneration for efficient doubled haploid production in ...

  19. Cryopreservation and plant regeneration of anther callus in Hevea ...

    African Journals Online (AJOL)

    Callus induced from anther of Hevea brasiliensis was successfully cryopreserved in liquid nitrogen (LN) by vitrification method and subsequently regenerated into plants. The effects of different preculture time, loading and dehydration duration on callus viability after cryopreservation were evaluated. The effective ...

  20. Androgenic potential and anther in vitro culture of Lagenaria ...

    African Journals Online (AJOL)

    Androgenic potential and anther in vitro culture of Lagenaria siceraria (Molina) Standl an edible-seed cucurbit. Kouakou Laurent Kouakou, Tra Serge Doubi, Tra Serge Koffi, Kouadio Ignace Kouassi, Tanoh Hilaire Kouakou, Jean-Pierre Baudoin, Irié Arsène Zoro Bi ...

  1. Cloning and sequence analysis of the defective in anther ...

    African Journals Online (AJOL)

    To clone the defective in anther dehiscence1 (DAD1) gene fragment of Chinese kale, about 700 bp product was obtained by PCR amplification using Chinese kale genomic DNA as the template and a pair of specific primers designed according to the conserved sequence of DAD1 genes of Arabidopsis thaliana and ...

  2. Attempts to induce haploids in anther cultures of sugar, fodder and wild species of beet

    Directory of Open Access Journals (Sweden)

    Janina Rogozińska

    2014-01-01

    Full Text Available In the present investigation, aimed at obtaining beet haploids from anthers, the effect of mineral media, potato and sugar beet extract and p-fluorophenylalanine (PFP in combination with growth substances was tested. Nutrient-starved plants as anther-donors, anther-starvation, cold treatment and photoperiod were also analysed. On all mineral media the anthers produced callus and roots; however, the percentage depended on the combination of growth substances used. The best medium for differentiation was that of Linsmaier and Skoog with 25 µM zeatin or 6-(3-methyl-2-butenylaminopurine with 5 µM naphthalene-l-acetic acid (25.5%. The addition of PFP caused an increase in the percentage of anther differentiation (41.6%. Besides callus and roots on one of the anthers (in ca. 140000 tested, vegetative buds were formed from which numerous plants were obtained (2n. Plant and anther nutrient starvation did not improve the anther response to differentiation, nor did it induce haploid development, similarly as cold treatment of inflorescences or isolated anthers. The anthers of wild species showed lower ability to differentiate than those of sugar or fodder beets. Cytological analyses showed formation of multicellular structures until ca. the 12-th day of anther culture; afterwards, they degenerated.

  3. ROLE OF POLYAMINES IN INHIBITION OF ETHYLENE BIOSYNTHESIS AND THEIR EFFECTS ON RICE ANTHER CULTURE DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Iswari S. Dewi

    2016-10-01

    Full Text Available The polyamines such as putrescine, spermidine, and spermine were reported to increase green plant regeneration in rice anther culture. Low response of anther culture of rice sub-species indica may be improved with the addition of putrescine in the culture media. Four experiments were conducted to study the role of polyamines in inhibition of ethylene biosynthesis and their effects on rice anther culture development. Anthers of two subspecies of rice, indica (IR64, Krowal, Jatiluhur and japonica (Taipei 309 were cultured onto media supplemented with putrescine (N6P and without putrescine (N6. Youngpanicles containing the anthers at mid-to-late nucleate microspores were cold pretreated at 5 + 2°C and incubated in the dark for 8 days before the anthers were cultured. Resultsshowed that medium without putrescine produced an earlier senescence of indica rice anther than that of japonica. The addition of 10-3 M putrescine into the culture media inhibited ethylene biosynthesis as anther senescence delayed, increased the three polyamines contents, and decreased the ACC content as well as ACC oxydase activity in anther-derived calli. In the anther and anther-derived calli of subspecies indica, the totalpolyamines content was lower (10.14 nM g-1 anther and 8.48 nM g-1 calli than that of subspecies japonica (12.61 nM g-1 anther and 10.16 nM g-1 calli, whereas the ethylene production was higher (32.31 nM g-1 anther and 2.48 nM g-1 calli than the japonica (31.68 nM g-1 anther and 1.76 nM g-1 calli. This study suggests that application of 10-3 M putrescine in anther culture of rice subspecies indica improves androgenesis by inhibitingearly senescence of cultured anthers and enhancing embryo or callus formation from microspores.

  4. High production of wheat double haploids via anther culture

    Directory of Open Access Journals (Sweden)

    Kondić-Šipka Ankica

    2007-01-01

    Full Text Available Androgenous and regeneration abilities of 14 randomly selected F1 hybrids of wheat (Triticum aestivum L. were analyzed. Anthers were grown in vitro on a modified Potato-2 inductive medium. The hybrid NS111-95/Ana had the highest average values for androgenous capacity (33% and callus yield (119%, while the hybrid NS 92-250/Tiha had the lowest values for these traits (9 and 21%, respectively. Seven genotypes (50% had a frequency of green plants relative to the number of isolated anthers of over 10%, with the highest frequency of 21.3% (NS111-95/Sremica. This hybrid produced 12.8 doubled haploid (DH lines per spike used for isolation. In the other genotypes, the number of produced DH lines per spike ranged from 1 (30­Sc.Smoc.88-89/Hays-2 to 11.2 (NS111-95/Ana. As half of the randomly selected genotypes exhibited high green plant regeneration ability and a high production of DH lines per spike, it can be concluded that in vitro anther culture can be successfully used in breeding programs for rapid production of homozygous wheat lines.

  5. Anther specializations related to the division of labor in Microlicia cordata (Spreng. Cham. (Melastomataceae

    Directory of Open Access Journals (Sweden)

    Mariana de Souza Carvalho Velloso

    2018-03-01

    Full Text Available ABSTRACT In heterantherous flowers, some anthers have an attraction and feeding function, while others are related to plant reproduction. Microlicia cordata has dimorphic stamens organized in two cycles: the antesepalous one with large stamens and pink anthers, and the antepetalous one with small stamens and yellow anthers. Division of labor was analyzed using the parameters of structure, composition, amount and estimated viability of pollen, and the color of floral parts. The anthers of the pollinating stamens were larger than the anthers of the feeding stamens, although anatomically similar. There was a difference in the amount of pollen produced by the anthers of the two cycles, but no difference was found in pollen viability. Considering a bee color vision model, the color of the anthers of the pollinating stamens contrasted less with that of the corolla, and thus is probably less attractive to visitors. Conversely, the anthers of the feeding stamens and the ventral appendage of the connective of the pollinating stamens contrasted more with the corolla, presenting the same color to the pollinators. These results are in accordance with the idea of division of labor among anthers of heterantherous flowers, especially regarding the quantity of pollen and the color of the floral parts.

  6. Genetic Architecture of Anther Extrusion in Spring and Winter Wheat

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    Quddoos H. Muqaddasi

    2017-05-01

    Full Text Available Hybrid wheat breeding is gaining prominence worldwide because it ensures higher and more static yield than conventionally bred varieties. The cleistogamous floral architecture of wheat (Triticum aestivum L. impedes anthers inside the floret, making it largely an inbreeder. For hybrid seed production, high anther extrusion is needed to promote cross pollination and to ensure a high level of pollen availability for the seed plant. This study, therefore, aimed at the genetic dissection of anther extrusion (AE in panels of spring (SP, and winter wheat (WP accessions by genome wide association studies (GWAS. We performed GWAS to identify the SNP markers potentially linked with AE in each panel separately. Phenotypic data were collected for 3 years for each panel. The average levels of Pearson's correlation (r among all years and their best linear unbiased estimates (BLUEs within both panels were high (r(SP = 0.75, P < 0.0001;r(WP = 0.72, P < 0.0001. Genotypic data (with minimum of 0.05 minor allele frequency applied included 12,066 and 12,191 SNP markers for SP and WP, respectively. Both genotypes and environment influenced the magnitude of AE. In total, 23 significant (|log10(P| > 3.0 marker trait associations (MTAs were detected (SP = 11; WP = 12. Anther extrusion behaved as a complex trait with significant markers having either favorable or unfavorable additive effects and imparting minor to moderate levels of phenotypic variance (R2(SP = 9.75−14.24%; R2 (WP = 9.44−16.98%. All mapped significant markers as well as the markers within their significant linkage disequilibrium (r2 ≥ 0.30 regions were blasted against wheat genome assembly (IWGSC1+popseq to find the corresponding genes and their high confidence descriptions were retrieved. These genes and their orthologs in Hordeum vulgare, Brachypodium distachyon, Oryza sativa, and Sorghum bicolor revealed syntenic genomic regions potentially involved in flowering-related traits. Moreover, the

  7. Obtaining barley haploid embryos and seedlings using anther culture technique

    International Nuclear Information System (INIS)

    Arabi, M.I.E.; Al-Safadi, B.; Mir Ali, N.

    2000-01-01

    The effect of three barley genotypes (Igri, Arabi abiad, and Taqa 76), three irradiation doses (0, 5, and 10 Gy), and two media (FW, modified FW), on the number of formed embryos, and the ratio between regenerated embryos to green seedlings and albinos, were studied using anther culture. Also the study involved the compatibility between seedling morphology and chromosome number. results indicated significant differences among the genotypes, and media in callus and embryos formation and also in the ratio and albino seedlings. However, the effect of gamma rays dose was significant only on embryos regeneration. A high percentage of compatibility (90%) was obtained between the seedling morphology and chromosome number. (author)

  8. Aquaporins of the PIP2 class are required for efficient anther dehiscence in tobacco.

    Science.gov (United States)

    Bots, Marc; Vergeldt, Frank; Wolters-Arts, Mieke; Weterings, Koen; van As, Henk; Mariani, Celestina

    2005-03-01

    Several processes during sexual reproduction in higher plants involve the movement of water between cells or tissues. Before flower anthesis, anther and pollen dehydration takes place before the release of mature pollen at dehiscence. Aquaporins represent a class of proteins that mediates the movement of water over cellular membranes. Aquaporins of the plasmamembrane PIP2 family are expressed in tobacco (Nicotiana tabacum) anthers and may therefore be involved in the movement of water in this organ. To gain more insight into the role these proteins may play in this process, we have analyzed their localization using immunolocalizations and generated plants displaying RNA interference of PIP2 aquaporins. Our results indicate that PIP2 protein expression is modulated during anther development. Furthermore, in tobacco PIP2 RNA interference plants, anther dehydration was slower, and dehiscence occurred later when compared with control plants. Together, our results suggest that aquaporins of the PIP2 class are required for efficient anther dehydration prior to dehiscence.

  9. Anther and isolated microspore culture of wheat lines from northwestern and eastern Europe

    DEFF Research Database (Denmark)

    Holme, I B; Olesen, A; Hansen, N J P

    1999-01-01

    Hexaploid wheat genotypes from north-western Europe show low responses to current anther culture techniques. This phenomenon was investigated on 145 north-western European wheat lines. Twenty-seven lines from eastern Europe were included to observe the response pattern of wheat from an area, where...... the technique has been used successfully. On average, eastern European wheat lines produced 3.6 green plants per 111 anthers, while only 1.4 green plants per 111 anthers were obtained in north-western European lines. This difference was due to the high capacity for embryo formation among the eastern European...... lines, while the ability to regenerate green plants was widespread in both germplasm groups. Isolated wheat microspore culture performed on 85 of these wheat lines gave an average 3.7-fold increase in green plants per anther compared with the anther culture response. The increased recovery of green...

  10. Meiosis of anther culture regenerants in asparagus (Asparagus officinalis L.

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    Leonardo Galli

    1998-03-01

    Full Text Available Pollen mother cells obtained from regenerated plants of asparagus (Asparagus officinalis L., in a population composed exclusively of male plants, through the process of anther culture from the hybrid G27 X 22-8, were analyzed during meiosis. It was observed that, during theprocess of anther culture by organogenesis, the pollen mother cells of the regenerants had great genomic instability, as evidenced by disturbances in all the meiotic phases of the first and second division. Furthermore, structural chromosomal abnormalities, in addition to aneuploidy and polyploidy, were observed.Foi analisada a meiose em células mãe de pólen de plantas de aspargo (Asparagus officinalis L. de uma população composta exclusivamente de plantas masculinas, obtidas através do processo de cultura de anteras do híbrido G27 X 22-8. Foi observado que, durante o processo de cultura de anteras, via calogênese, as células mãe de pólen dos regenerantes apresentaram grande instabilidade genômica, evidenciada por irregularidades nas fases de diacinese, assim como de metáfase, anáfase, telófase da primeira e segunda divisão meiótica. Além disto, o processo originou anormalidades cromossômicas estruturais em adição às aneuploidias e poliploidias.

  11. Anther development and microsporegenesis in Gossypium herbaceum L.

    Directory of Open Access Journals (Sweden)

    Zahra Tajik Khaveh

    2016-11-01

    Full Text Available Gosseypium herbaceum L. is known as cotton plant belongs to the family Malvaceae. This plant is widely distributed throughout western India, Africa, Middle East countries, central Asia, and Availability is found in Iran, Afghanistan, Russian and Turkistan. Gossypium herbaceum L. is a cultivateda cotton species (2n=2x =26,A₁ A₁ has favorable traits such as excellent drought tolerance and resistance to sucking insects and leaf curl virus. In this study, microsporegenesis and anther development of G.herbaceum were studied. The flower, in different developmental stages, were removed, fixed in formalin-glacial acetic acid- lcohol(FAA,stored in 70%ethanol,embedded in paraffin and then sliced at 8-10Mm by rotary microtom. Staining was carried out by periodic Acid Shiff (PASand contrasted with hematoxylin. Scanning electron microscope(SEM was used to analyze the mature pollen grains. The results indicated that anthers wall development followed the dicotyledonous type and were tetrasporangiate which composed of epidermal layer, endotheciumlayer, middle layer and tapetum layer.

  12. Research on cotton anther development of three male-sterile lines

    International Nuclear Information System (INIS)

    Dou Liping; Tang Canming; Yue Jieyu; Wang Qingya

    2009-01-01

    Pollens of Sumian 22 were irradiated by 60 Co γ-rays at a dose of 20Gy, then fertilized to pistil and harvested seed. Three male-sterile lines were selected from M 1 plants, their anther observed by paraffin slice technique. Although there were some different characteristics during the abortion anther development, the abortion was consistent: the abortion stage from the development periods of pollen mother cells to microspore, pollen mother cells, tapetum, middle layer cells and the shape of anther were affected, the results contained micronucleus and double nucleus, cytoplasm expansion during the period of meiosis, tapetum and middle layer cells and so on were abnormal. (authors)

  13. Genetic analysis of anther culture response in maize.

    Science.gov (United States)

    Petolino, J F; Thompson, S A

    1987-06-01

    Response frequencies in maize (Zea mays L.) anthers cultured in vitro were examined in a diallel set of crosses among four commercial inbred lines. Significant differences among the genotypes were observed, with the crosses H99xFR16 and Pa91xFR16 displaying the highest responses. General (GCA) and specific (SCA) combining ability mean squares were calculated and determined to be highly significant. GCA effects among the parental lines were highest for FR16 and lowest for LH38. Nongenotypic, plant-toplant differences were also found to make a significant contribution to the overall variation observed. The results from this study indicate that parents which give rise to highly responsive hybrids can be identified and that genetic improvement is possible through selection.

  14. Anther development stage and gamma radiation effects on tomato anther-derived callus formation; Efeitos do estadio de desenvolvimento da antera e da radiacao gama na formacao de calos derivados de anteras de tomate

    Energy Technology Data Exchange (ETDEWEB)

    Brasileiro, Ana Christina R.; Willadino, Lilia [Universidade Federal Rural de Pernambuco, Recife, PE (Brazil). Lab. de Cultura de Tecidos Vegetais. E-mail: lilia@truenet.com.br; Guerra, Marcelo [Pernambuco Univ., Recife, PE (Brazil). Dept. de Botanica. Lab. de Citogenetica Vegetal; Colaco, Waldeciro [Pernambuco Univ., Recife, PE (Brazil). Dept. de Energia Nuclear. Lab. de Radioagronomia; Meunier, Isabelle [Universidade Federal Rural de Pernambuco, Recife, PE (Brazil). Dept. de Engenharia Florestal; Camara, Terezinha R. [Universidade Federal Rural de Pernambuco, Recife, PE (Brazil). Dept. de Quimica. Lab. de Cultura de Tecidos Vegetais

    1999-12-01

    Two experiments were carried (I) to determine tomato anther development stage influence on callus production; and (II) to investigate gamma radiation effects on anther culture. In the first experiment, anthers of a tomato hybrid (IPA 5 x Rotam 4-F{sub 1}) were grown on three media. Although calli were induced at all stages of anther development, varying from prophase I to mono nucleate microspore, callus frequency decreased as anther development progressed and calli induction were not significantly affected by all media tested. Anthers containing prophase I meiocytes produced the highest calli frequency. Anther and flower bud length both were significantly correlated with anther development stage. In the second experiment, seed and floral buds of tomato hybrids IPA 5 x Rotam 4 (F{sub 2}), IPA 6 x Rotam 4 (F{sub 2}) and IPA 8 x 217.1 (F{sub 2}) were submitted to gamma-ray and anthers were plated on two media described by Gresshoff and Doy (1972) supplemented with 2.0 mg L{sup -1} NAA + 5.0 mg L{sup -1} KIN and 2.0 mg L{sup -1} NAA + 1.0 mg L{sup -1} KIN. No significant differences for genotype and dosage testes were found for calli formation. (author)

  15. Performance of dihaploid wheat lines obtained via anther culture

    Directory of Open Access Journals (Sweden)

    Salomon Marcus Vinicius

    2003-01-01

    Full Text Available The anther culture technique has been used in breeding programs to obtain haploid plants from hybrid plants of F1 generation and to develop more efficiently wheat cultivars. To study the behavior of dihaploid wheat lines and two check cultivars, IAC-24 and IAC-289, experiments were carried out under sprinkler irrigation at Monte Alegre do Sul, SP, Brazil, in an Haplic Acrisol and at Tatuí, SP, Brazil, in a Rhodic Ferrasol, during the years 1999 and 2000. Genotypes were evaluated for grain yield, 100 grain weight, plant height, resistance to leaf rust (Puccinia recondita f. sp. tritici Rob. Desm. and lodging. The genotypes were also evaluated under laboratory conditions for their Al+3 toxicity tolerance using nutrient solutions. The line 8, originated from ANA/IAC-24 cross, presented high grain yield, semidwarf plant type, heavy grain, leaf rust resistance and tolerance to Al+3 toxicity. The lines 4, 11, 12 and 14, also presented high tolerance to Al+3 toxicity in association to grain yield above 3.000 kg ha-1. These lines are suitable to be used in breeding programs to develop cultivars for acid soils.

  16. Cold stress alters transcription in meiotic anthers of cold tolerant chickpea (Cicer arietinum L.).

    Science.gov (United States)

    Sharma, Kamal Dev; Nayyar, Harsh

    2014-10-11

    Cold stress at reproductive phase in susceptible chickpea (Cicer arietinum L.) leads to pollen sterility induced flower abortion. The tolerant genotypes, on the other hand, produce viable pollen and set seed under cold stress. Genomic information on pollen development in cold-tolerant chickpea under cold stress is currently unavailable. DDRT-PCR analysis was carried out to identify anther genes involved in cold tolerance in chickpea genotype ICC16349 (cold-tolerant). A total of 9205 EST bands were analyzed. Cold stress altered expression of 127 ESTs (90 up-regulated, 37 down-regulated) in anthers, more than two third (92) of which were novel with unknown protein identity and function. Remaining about one third (35) belonged to several functional categories such as pollen development, signal transduction, ion transport, transcription, carbohydrate metabolism, translation, energy and cell division. The categories with more number of transcripts were carbohydrate/triacylglycerol metabolism, signal transduction, pollen development and transport. All but two transcripts in these categories were up-regulated under cold stress. To identify time of regulation after stress and organ specificity, expression levels of 25 differentially regulated transcripts were also studied in anthers at six time points and in four organs (anthers, gynoecium, leaves and roots) at four time points. Limited number of genes were involved in regulating cold tolerance in chickpea anthers. Moreover, the cold tolerance was manifested by up-regulation of majority of the differentially expressed transcripts. The anthers appeared to employ dual cold tolerance mechanism based on their protection from cold by enhancing triacylglycerol and carbohydrate metabolism; and maintenance of normal pollen development by regulating pollen development genes. Functional characterization of about two third of the novel genes is needed to have precise understanding of the cold tolerance mechanisms in chickpea anthers.

  17. The Distribution Features of Polysaccharides and Lipids in the Development of Tomato Anthers

    Directory of Open Access Journals (Sweden)

    Zhu Yun

    2015-07-01

    Full Text Available The regulation of nutrient transportation and transformation in developing anthers is very complex. We analyzed the distribution and features of polysaccharides and lipids in the developing anthers of tomatoes using histochemical methods. Some starches appeared in the connective somatic tissue of anthers during the sporogenous cell stage. Before meiosis of the microspore mother cell, a thick polysaccharide callose wall was formed, accompanied by a reduction in the connective tissue starches. During the tetrad stage after meiosis, the polysaccharide material in the anther did not change. At the early microspore stage, the starches in the connective cells again increased, and polysaccharide material appeared in the partial intine of pollen. At the late microspore stage, a large vacuole formed that did not contain lipids or starches, and only the pollen wall contained red polysaccharides. At this stage, the connective somatic cell starch amounts decreased, and the tapetal cells changed shape and degenerated. After microspore division, abundant lipids appeared in the bicellular pollen, and starches accumulated following pollen development. As the anthers matured, many lipids and some starches accumulated in the epidermal cells. Nutrient metabolism within the tomato pollen characteristically accumulated lipids first and then starches, while the mature pollen accumulated starches and lipids simultaneously. This characteristic pattern of nutrient metabolism in tomato pollen shows species specificity among plants.

  18. Pretreatment Stress Enhances Embryogenic Callus Production in Anther Culture of Sturt's Desert Pea (Swainsona formosa

    Directory of Open Access Journals (Sweden)

    ZULKARNAIN

    2007-03-01

    Full Text Available The aims of the experiment were to investigate the effect of pretreatment stress on the proliferation of anther-derived embryogenic callus, and its subsequent embryo regeneration in Swainsona formosa. Anthers were pretreated in starvation medium at cold (4 °C temperature and cultured. Cultures were initially placed in darkness for four weeks, followed by 16-h photoperiod at 25 ± 1 °C. The stress pretreatment was found to enhance embryogenic callus formation on cultured anthers. Further, somatic embryos were successfully regenerated from embryogenic callus upon transferred onto regeneration medium supplemented with 1% sucrose and 4.63 µM kinetin, and later plantlets were obtained. Meanwhile, nonembryogenic callus continued to grow resulting in more callus mass without showing any embryoid initiation.

  19. Development of anthers and pollen in Brazilian heterostylic species of Erythroxylum (Erythroxylaceae): an ecological approach

    International Nuclear Information System (INIS)

    Silva, L.D.; Fernandes, C. L.

    2016-01-01

    This study describes the development of anthers and pollen in heterostylic flowers of two species of Erythroxylum. The features of anthers and their developmental pattern, which is of the dicotyledonous type, do not vary according to morphs or species. The pollen grains of both morphs show differences in their morphology, development, and content stored as a reserve source. In both species, thrum (short-styled) flowers presented bicellular pollen grains, while pin (long-styled) ones yielded bi- and tricellular pollen grains. The presence of inviable pollen grains in the two flower morphs of both species and the malformation of one of the four microsporanges in the thrum flowers of E. campestre are noteworthy. We verified that features found both in the anther wall and in the pollen grains could be related to the reproductive success and adaptation of the species to the Brazilian savanna biome. (author)

  20. Efficiency of anther culture technique in the production of wheat double haploids

    Directory of Open Access Journals (Sweden)

    Kondić-Špika Ankica Đ.

    2008-01-01

    Full Text Available The objective of the study was to investigate efficiency of anther culture in the production of spontaneous double haploids from randomly selected heterozygous genotypes of wheat (Triticum aestivum L.. Anthers of 20 F1 wheat combinations were grown in vitro on a modified Potato-2 medium. All of the examined genotypes have shown the ability to produce pollen calluses as well as to regenerate green plants. On average for the whole experiment material, 47.2 calluses were produced per 100 cultured anthers. The green plant regeneration ranged from 0.8 to 13.4 green plants per spike, with an overall mean of 5.8. From the total of 582 regenerated green plants, 47.9% (279 were spontaneous double haploids. The final average yield from the study was 2.8 double haploids per spike.

  1. Expression and regulation of two novel anther-specific genes in Lilium longiflorum.

    Science.gov (United States)

    Tzeng, Jhih-Deng; Hsu, Ssu-Wei; Chung, Mei-Chu; Yeh, Fung-Ling; Yang, Chin-Ying; Liu, Ming-Che; Hsu, Yi-Feng; Wang, Co-Shine

    2009-03-01

    Two stage-specific genes have been isolated from a subtractive cDNA library constructed from developing anthers of lily (Lilium longiflorum). The proteins encoded by the two genes have a strong hydrophobic region at the N-terminus, indicating the presence of a signal peptide. The deduced LLA-67 is a new type of small cysteine-rich protein whose sequence exhibits four consecutive CX(3)CX(6-10) repeats that could form signal-receiving finger motifs, while the deduced LLA-115 protein shows significant similarities to a rice unknown protein, and putative cell wall proteins of Medicago truncatula and Arabidopsis. The transcripts of LLA-67 and LLA-115 were anther specific and differentially detected at the phase of microspore development. In situ hybridization with antisense riboprobes of the two genes in the anther showed strong signals localized to the tapetal layer of the anther wall. The LLA-67 mRNA was also detected in the microspore at the phase of microspore development but the LLA-115 mRNA was not. The LLA-115 gene can be exogenously induced by gibberellin (GA), whereas the LLA-67 gene cannot be induced. Studies with the GA biosynthesis inhibitor uniconazole and an inhibitor of ethylene activity, 2,5-norbornadien (NBD), revealed that the two genes were negatively regulated by ethylene and a cross-talk between GA and ethylene was involved in the regulation of the two genes occurring in young anthers. The treatment of NBD caused the tapetum to become densely cytoplasmic and highly polarized, whereas uniconazole arrested tapetal development to a status close to that of control. DNA blots of lily genomic DNA indicated that the two genes were encoded by a small gene family. The different actions of hormones on gene expression and the possible function of the gene products in young anthers are discussed.

  2. Improvement of rice anther culture and application of the technique in mutation breeding

    International Nuclear Information System (INIS)

    Chen Qiufang; Wang Cailian; Lu Yimei; Jin Wei

    2001-01-01

    The ability of callus formation and green plant regeneration was very different for different rice type and varieties in anther culture. The differentiation and regeneration of green plants were obviously improved when the rice anthers at about 30 d after culture on induction medium were irradiated with 20 Gy of γ-rays and calli were cultured on the differentiation medium containing 30 mg/L colchicines. The stimulation effect of γ-irradiation combined with colchicines was much better than that of their single use. Mutation frequency and selective efficiency in M 2 were obviously increased by application of the technique

  3. [Analysis of genetic control of maize response in anther culture within a diallelic set].

    Science.gov (United States)

    Satarova, T N

    2002-01-01

    The androgenic ability in anther culture in vitro was examined within a diallel set of five maize lines. The complex analysis of genetic variation components, Hayman's diagram, and genetic parameters showed that the anther response is under the control of an additive-dominant genetic system. The examined lines possessed the different correlation of dominant and recessive alleles controlling androgenesis. And 44 was the line with the biggest number of recessive genes, which determined the increase in the trait. The level of dominance varied in different loci, though in the whole the degree of dominance approached to the complete one.

  4. SHI/STY Genes Affect Pre- and Post-meiotic Anther Processes in Auxin Sensing Domains in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Leandro H. Estornell

    2018-02-01

    Full Text Available In flowering plants, mature sperm cells are enclosed in pollen grains formed in structures called anthers. Several cell layers surrounding the central sporogenous cells of the anther are essential for directing the developmental processes that lead to meiosis, pollen formation, and the subsequent pollen release. The specification and function of these tissues are regulated by a large number of genetic factors. Additionally, the plant hormone auxin has previously been shown to play important roles in the later phases of anther development. Using the R2D2 auxin sensor system we here show that auxin is sensed also in the early phases of anther cell layer development, suggesting that spatiotemporal regulation of auxin levels is important for early anther morphogenesis. Members of the SHI/STY transcription factor family acting as direct regulators of YUC auxin biosynthesis genes have previously been demonstrated to affect early anther patterning. Using reporter constructs we show that SHI/STY genes are dynamically active throughout anther development and their expression overlaps with those of three additional downstream targets, PAO5, EOD3 and PGL1. Characterization of anthers carrying mutations in five SHI/STY genes clearly suggests that SHI/STY transcription factors affect anther organ identity. In addition, their activity is important to repress periclinal cell divisions as well as premature entrance into programmed cell death and cell wall lignification, which directly influences the timing of anther dehiscence and the pollen viability. The SHI/STY proteins also prevent premature pollen germination suggesting that they may play a role in the induction or maintenance of pollen dormancy.

  5. Determination of suitable microspore stage and callus induction from anthers of kenaf (Hibiscus cannabinus L.).

    Science.gov (United States)

    Ibrahim, Ahmed Mahmood; Kayat, Fatimah Binti; Hussin, Zeti Ermiena Surya Mat; Susanto, Dwi; Ariffulah, Mohammed

    2014-01-01

    Kenaf (Hibiscus cannabinus L.) is one of the important species of Hibiscus cultivated for fiber. Availability of homozygous parent lines is prerequisite to the use of the heterosis effect reproducible in hybrid breeding. The production of haploid plants by anther culture followed by chromosome doubling can be achieved in short period compared with inbred lines by conventional method that requires self pollination of parent material. In this research, the effects of the microspore developmental stage, time of flower collection, various pretreatments, different combinations of hormones, and culture condition on anther culture of KB6 variety of Kenaf were studied. Young flower buds with immature anthers at the appropriate stage of microspore development were sterilized and the anthers were carefully dissected from the flower buds and subjected to various pretreatments and different combinations of hormones like NAA, 2,4-D, Kinetin, BAP, and TDZ to induce callus. The best microspore development stage of the flower buds was about 6-8 mm long collected 1-2 weeks after flower initiation. At that stage, the microspores were at the uninucleate stage which was suitable for culture. The best callus induction frequency was 90% in the optimized semisolid MS medium fortified with 3.0 mg/L BAP + 3.0 mg/L NAA.

  6. Haploid plant production in Zantedeschia aethiopica ‘Hong Gan’ using anther culture

    NARCIS (Netherlands)

    Zhang, X.; Wu, Q.; Li, X.; Zheng, S.; Wang, S.; Guo, L.; Zhang, L.; Custers, J.B.M.

    2011-01-01

    This report describes advances in the anther culture of Zantedeschia aethiopica. Important factors for improvement as compared to the earlier procedure were: (1) using flowers from inflorescences developed at relatively low temperature during winter, (2) high temperature stress treatment at 32 °C

  7. Determination of Suitable Microspore Stage and Callus Induction from Anthers of Kenaf (Hibiscus cannabinus L.

    Directory of Open Access Journals (Sweden)

    Ahmed Mahmood Ibrahim

    2014-01-01

    Full Text Available Kenaf (Hibiscus cannabinus L. is one of the important species of Hibiscus cultivated for fiber. Availability of homozygous parent lines is prerequisite to the use of the heterosis effect reproducible in hybrid breeding. The production of haploid plants by anther culture followed by chromosome doubling can be achieved in short period compared with inbred lines by conventional method that requires self pollination of parent material. In this research, the effects of the microspore developmental stage, time of flower collection, various pretreatments, different combinations of hormones, and culture condition on anther culture of KB6 variety of Kenaf were studied. Young flower buds with immature anthers at the appropriate stage of microspore development were sterilized and the anthers were carefully dissected from the flower buds and subjected to various pretreatments and different combinations of hormones like NAA, 2,4-D, Kinetin, BAP, and TDZ to induce callus. The best microspore development stage of the flower buds was about 6–8 mm long collected 1-2 weeks after flower initiation. At that stage, the microspores were at the uninucleate stage which was suitable for culture. The best callus induction frequency was 90% in the optimized semisolid MS medium fortified with 3.0 mg/L BAP + 3.0 mg/L NAA.

  8. Cloning and expression analysis of a new anther-specific gene ...

    Indian Academy of Sciences (India)

    The expression of CaMF4 was detected in both the flower buds at stage 8 and open flowers of the male fertile line. In contrast to this observation, expression of CaMF4 was not detected in any organs of the male sterile line. Further analysis revealed that CaMF4 was expressed particularly in anthers of the fertile line.

  9. Microspore embryogenesis in barley: anther pre-treatment stimulates plant defence gene expression

    NARCIS (Netherlands)

    Jacquard, C.; Mazeyrat-Gourbeyre, F.; Devaux, P.; Boutilier, K.A.

    2009-01-01

    Microspore embryogenesis (ME) is a process in which the gametophytic pollen programme of the microspore is reorientated towards a new embryo sporophytic programme. This process requires a stress treatment, usually performed in the anther or isolated microspores for several days. Despite the

  10. Effect of AgNO 3 on androgenesis of Brassica oleracea L. anthers ...

    African Journals Online (AJOL)

    The present article is a synthesis study accomplished at Vegetable Research and Development Station Bacau regarding the implication of silver nitrate (AgNO3) in modulating the morphogenetic reaction of white cabbage anthers cultivated in vitro. According to literature, silver nitrate is a strong inhibitor of ethylene action.

  11. Mutant in tobacco anther culture induced by 60Co γ-rays

    International Nuclear Information System (INIS)

    Tong Daoru; Jia Xinghua

    1991-01-01

    The tobacco anthers at uninucleate eccentric stage were irradiated by 60 Co γ-rays for the purpose of inducing desirable mutants. The results showed that the induction frequency of plantlets increased following 1kR of 60 Co γ-rays treatment. However, the time of plantlet induction was delayed and the percentage of responding anthers as well as the number of plantlets induced per anther significantly decreased after 3kR of 60 Co γ-ray radiation which was considered as a semilethal exposure. The plantlet numbers induced per anther were extremely low following 6kR of 60 Co γ-ray radiation. A white flower mutant appeared in the induced progenies. The tobacco leaf quality of this mutant were significantly improved as compared with its parental line. The mutant line has been tested and proved to have commercial value though the resistance to the black shank of tobacco slightly decreased as compared with the parental line

  12. Cloning and expression analysis of a new anther-specific gene ...

    Indian Academy of Sciences (India)

    separation of the sporogenous cells, microspore mitosis, pollen differentiation and others (Glover et al. 1988). Anther and pollen formation, and development are a critical period in the plant life cycle, which involves the precise expression of coordinated genes and a wide variety of gene interactions (Goldberg et al. 1993).

  13. Multiploidy occurrence in tomato calli from anther culture | Julião ...

    African Journals Online (AJOL)

    ... duration did not directly influence the occurrence of endoreduplication. In this work, this type of somaclonal variation has been reported for the first time in tomato anther culture, and their possible origin has been discussed. Key words: Callogenesis, flow cytometry, polyploidy, Solanum lycopersicum, somaclonal variation.

  14. Cloning and expression analysis of a new anther-specific gene ...

    Indian Academy of Sciences (India)

    Cloning and expression analysis of a new anther-specific gene CaMF4 in Capsicum annuum. XUEFENG HAO1,2, CHANGMING CHEN2, GUOJU CHEN2, BIHAO CAO2 and JIANJUN LEI1,2∗. 1Department of Biology, Taiyuan Normal University, Taiyuan 030012, Shanxi Province, People's Republic of China. 2College of ...

  15. Shifts from specialised to generalised pollination systems in Miconieae (Melastomataceae) and their relation with anther morphology and seed number.

    Science.gov (United States)

    Brito, V L G; Fendrich, T G; Smidt, E C; Varassin, I G; Goldenberg, R

    2016-07-01

    Most species in Melastomataceae have poricidal anthers related to specialised bee buzz-pollination, while some have anthers with large openings associated to non-bee pollination systems. We tracked the evolution of anther morphology and seed number on the Miconieae phylogenetic tree to understand the evolutionary shifts in such pollination systems. Anther morphometric data and seed number were recorded for 54 taxa. Pollinators (bees, flies, wasps) were recorded for 20 available species. Ancestral state reconstruction was made using Maximum Likelihood from nrITS sequences. We used phylogenetic eigenvector regressions to estimate phylogenetic signal and the adaptive component for these traits. Species pollinated by bees or bees and wasps tend to have smaller pores and fruits with more seeds. Species pollinated by flies or flies and bees and/or wasps tend to have larger pores and fruits with less seeds. Independent evolution occurred three times for anthers with large pores and twice for fruits with few seeds. We detected a phylogenetic signal in both traits, and negative correlated evolution between them. In actinomorphic small-flowered Miconieae, changes in anther morphology can be related to generalisation in the pollination system incorporating flies and wasps as pollinators and lessening the importance of buzzing bees in such process. Differences in pollen removal and deposition may explain differences in anther morphology and seed number in Miconieae. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  16. Effect of the genotype and gamma irradiation on the anther cultures of a 10x10 diallel cross of wheat

    International Nuclear Information System (INIS)

    Molina, L.; Aldana, F.

    2001-01-01

    Anther culture responsiveness, irradiation effect and reciprocal effect were evaluated on ten genotypes (V1-V10) and a 101x0 diallel cross. Gamma irradiation dose of 100 Gy was applied to seeds of parents and F 1 cross from which the donor plants were grown. Non-irradiated donor plants were also used for comparison. Anthers were plated on potato-2 callus induction medium and calli formed were transferred to MS medium supplemented with sucrose (3%), indolacetic acid (1.0 mg/L), kinetin (1.0 mg/L), inositol (100 mg/L) and solidified with agar (0.7%). Genotypes showed big differences for callus induction, plant regeneration and anther culturability rate. The most responsive materials were V2, V10 and V5 with 76.0, 27.4 and 10.8 green plants per 100 anthers respectively. No irradiation effect was found for the parents nor the F 1 crosses on the pooled data. Mean anther culture response of specific genotypes showed that irradiation significantly increased anther culturability rate of V3 from 0.1 to 27.6 green plants per 100 anthers. No reciprocal effect was observed. (author)

  17. Developing Tobacco Lines Resistant to Powdery Mildew (Erysiphe cichoracearum L.) by Anther Culture Technique for the Aegean Region

    OpenAIRE

    GENCER, A. Saniye

    2014-01-01

    The anther culture technique as a biotechnological application was combined with conventional breeding methods in order to improve tobacco varieties' resistant to powdery mildew prevailing in the Aegean region of Turkey. For this, resistance was transferred to two varieties from a genitor by the backcross method leading to derive haploid plants from the cultured anthers of BC1 plants firstly, and dihaploid plants by acenaphthene or colchicine treatments secondly. A total of 14 dihapl...

  18. Evolution of the selfing syndrome: Anther orientation and herkogamy together determine reproductive assurance in a self-compatible plant.

    Science.gov (United States)

    Toräng, Per; Vikström, Linus; Wunder, Jörg; Wötzel, Stefan; Coupland, George; Ågren, Jon

    2017-09-01

    Capacity for autonomous self-fertilization provides reproductive assurance, has evolved repeatedly in the plant kingdom, and typically involves several changes in flower morphology and development (the selfing syndrome). Yet, the relative importance of different traits and trait combinations for efficient selfing and reproductive success in pollinator-poor environments is poorly known. In a series of experiments, we tested the importance of anther-stigma distance and the less studied trait anther orientation for efficiency of selfing in the perennial herb Arabis alpina. Variation in flower morphology among eight self-compatible European populations was correlated with efficiency of self-pollination and with pollen limitation in a common-garden experiment. To examine whether anther-stigma distance and anther orientation are subject to directional and/or correlational selection, and whether this is because these traits affect pollination success, we planted a segregating F2 population at two native field sites. Selection strongly favored a combination of introrse anthers and reduced anther-stigma distance at a site where pollinator activity was low, and supplemental hand-pollination demonstrated that this was largely because of their effect on securing self-pollination. The results suggest that concurrent shifts in more than one trait can be crucial for the evolution of efficient self-pollination and reproductive assurance in pollinator-poor habitats. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  19. Androgenesis in chickpea: Anther culture and expressed sequence tags derived annotation

    DEFF Research Database (Denmark)

    Panchangam, Sameera Sastry; Mallikarjuna, Nalini; Gaur, Pooran M.

    2014-01-01

    Double haploid technique is not routinely used in legume breeding programs, though recent publications report haploid plants via anther culture in chickpea (Cicer arietinum L.). The focus of this study was to develop an efficient and reproducible protocol for the production of double haploids...... with the application of multiple stress pre-treatments such as centrifugation and osmotic shock for genotypes of interest in chickpea for their direct use in breeding programs. Four genotypes, ICC 4958, WR315, ICCV 95423 and Arearti were tested for anther culture experiments. The yield was shown to be consistent...... was made to find putative candidates for androgenesis using Expressed Sequenced Tags (EST) and interolog based protein interaction analyses....

  20. PIP1 and PIP2 aquaporins are differentially expressed during tobacco anther and stigma development.

    Science.gov (United States)

    Bots, Marc; Feron, Richard; Uehlein, Norbert; Weterings, Koen; Kaldenhoff, Ralf; Mariani, Titti

    2005-01-01

    Several processes during sexual reproduction in higher plants involve the movement of water between cells or tissues, such as occurs during dehiscence of the anther and hydration of the pollen grain after it is deposited on a stigma. To get more insight in these processes, a set of putative aquaporins was cloned and it was found that at least 15 are expressed in reproductive organs, which indicates that the control of water flow is important for reproduction. Functional studies in Xenopus laevis oocytes using two of the cDNAs showed that NtPIP2;1 is an efficient aquaporin, whereas NtPIP1;1 is not. Expression studies on RNA and protein levels showed that PIP1 and PIP2 genes are differently expressed in reproductive organs: PIP1 RNA accumulates in the stigma, and PIP1 and PIP2 RNA can be detected in most tissues of the anther.

  1. DEAMINATION OF DEOXYCYTIDINE AND 5-METHYLDEOXYCYTIDINE IN DEVELOPING ANTHERS OF LILIUM LONGIFLORUM (VAR. CROFT)

    Science.gov (United States)

    Hotta, Yasuo; Stern, Herbert

    1961-01-01

    A study has been made of developmental variations in anthers of Lilium longiflorum with respect to the deamination of deoxycytidine and 5-methyldeoxycytidine. Although a periodicity of enzymatic activities surrounding the mitotic cycle has been found, the over-all evidence is against the significance of such periodicity to chromosome duplication. On the basis of evidence obtained a distinction has been drawn between enzyme systems functioning in a broad supporting role and those immediately tied to morphogenetic events. PMID:13716116

  2. Characterization of the global transcriptome for cotton (Gossypium hirsutum L.) anther and development of SSR marker.

    Science.gov (United States)

    Zhang, Xianwen; Ye, Zhenwei; Wang, Tiankang; Xiong, Hairong; Yuan, Xiaoling; Zhang, Zhigang; Yuan, Youlu; Liu, Zhi

    2014-11-10

    Cotton is an important fiber plant, and it's attractive to elucidate the molecular mechanism of anther development due to the close relationship between the anther fertility and boll-setting, and also fiber yield. In the present paper, 47.2 million paired-end reads with average length of 82.87 bp from the anthers of TM-1 (Gossypium hirsutum L.), a genetic standard line, were generated through transcriptome sequencing, and 210,965 unigenes of more than 100 bp were obtained. BLAST, KEGG, COG, and GO analyses showed that the genes were enriched in the processes of transcription, translation, and post-translation as well as hormone signal transduction, the transcription factor families, and cell wall-related genes mainly participating in cell expansion and carbohydrate metabolism. Further analysis identified 11,153 potential SSRs. A suit of 5122 primer pair sequences were designed, and 82 of 300 randomly selected primer pairs produced reproducible amplicons that were polymorphic among 22 cotton accessions from G. hirsutum, Gossypium barbadense and Gossypium arboreum. The UPGMA clustering analysis further confirmed high quality and effectiveness of these novel SSR markers. The present study provided insights into the transcriptome profile of the cotton and established a public information platform for functional genomics and molecular breeding. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. The effect of genotype on anther culture response of cultivated and wild oats

    Directory of Open Access Journals (Sweden)

    E. KIVIHARJU

    2008-12-01

    Full Text Available Anther culture ability was tested for 44 oat (Avena sativa L., six naked oat (A. sativa L., naked type and 15 wild oat (Avena sterilis L. genotypes, in addition to progeny of five intraspecific crosses of A. sativa and two interspecific crosses of A. sativa x A. sterilis. Anther culture response was affected considerably by genotype. Thirty one oat genotypes responded by callus growth on induction medium and seven of them produced embryo structures, two of the lines consistently. All naked oat genotypes produced embryo structures. Embryo production rates for the wild oat lines were comparable with those for the naked oat genotypes, and higher than for oat: 13 of the 15 genotypes tested produced embryo structures. Plant regeneration was possible only from wild oat. The regeneration ability was inherited in the progeny of the A. sativa x A. sterilis cross cv. Puhti x CAV 2648. The response of anthers of oat genotypes was inhibited by auxin on the induction medium, while naked oat, wild oat and A. sativa x A. sterilis crosses responded better on a medium containing 2,4-dichlorophenoxyacetic acid .;

  4. Differential Proteomic Analysis of Anthers between Cytoplasmic Male Sterile and Maintainer Lines in Capsicum annuum L.

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    Zhiming Wu

    2013-11-01

    Full Text Available Cytoplasmic male sterility (CMS, widely used in the production of hybrid seeds, is a maternally inherited trait resulting in a failure to produce functional pollen. In order to identify some specific proteins associated with CMS in pepper, two-dimensional gel electrophoresis (2-DE was applied to proteomic analysis of anthers/buds between a CMS line (designated NA3 and its maintainer (designated NB3 in Capsicum annuum L. Thirty-three spots showed more than 1.5-fold in either CMS or its maintainer. Based on mass spectrometry, 27 spots representing 23 distinct proteins in these 33 spots were identified. Proteins down-regulated in CMS anthers/buds includes ATP synthase D chain, formate dehydrogenase, alpha-mannosidas, RuBisCO large subunit-binding protein subunit beta, chloroplast manganese stabilizing protein-II, glutathione S-transferase, adenosine kinase isoform 1T-like protein, putative DNA repair protein RAD23-4, putative caffeoyl-CoA 3-O-methyltransferase, glutamine synthetase (GS, annexin Cap32, glutelin, allene oxide cyclase, etc. In CMS anthers/buds, polyphenol oxidase, ATP synthase subunit beta, and actin are up-regulated. It was predicted that male sterility in NA3 might be related to energy metabolism turbulence, excessive ethylene synthesis, and suffocation of starch synthesis. The present study lays a foundation for future investigations of gene functions associated with pollen development and cytoplasmic male sterility, and explores the molecular mechanism of CMS in pepper.

  5. Flavonoids in white and yellow perianths and yellow anthers of tulips (Tulipa gesneriana L.

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    Marcin Horbowicz

    2013-12-01

    Full Text Available The content of flavonoids in white and yellow perianths and yellow anthers of a few tulip cultivars were determined at the stage of full flowering. To analyses of flavonols a HPLC method was used. In anthers (yellow of all analyzed cultivars (Oscar, Pax, Profesor Wóycicki, Biała Dama, White Virgin, Calypso, Diana high content of quercetin (2,35 - 6,01 mg·g-1 F.W., kaempferol (1,09 - 9,47 mg·g-1 F.W. and apigenin (1,34 - 8,24 mg·g-1 F.W. was found. In analyzed white perianth of cvs. Oscar and White Virgin also high content of quercetin (1,3 - 1,80 mg·g-1 F.W. and kaempferol (1,90 mg·g-1 F.W. was documented and only traces of apigenin was found. In the yellow perianth of cv. Profesor Wóycicki the level of quercetin and kaempferol was much lower than in perianth of cvs. Oscar and White Virgin, and apigenin was absent. Thus, yellow anthers and white and yellow perianth of tulip cultivars are a rich source of flavonols.

  6. Development of a short duration upland rice mutant line through anther culture of gamma irradiated plants

    International Nuclear Information System (INIS)

    Kyin San Myint; Khine Oo Aung; Khin Soe

    2005-01-01

    This experiment was conducted in the field and at the tissue culture laboratory of the Plant Physiology Division, CARI, Yezin from 1994 to 1997. Upland rice, Yar-2 was used as the test variety. Dried seeds (14% moisture content) were treated with gamma rays at doses of 0, 300, 350, 400 and 450 Gy respectively. These seeds were planted separately according to the gamma-ray treatment they received. At booting stage, tillers were cut. Anthers from the top and middle portion of the panicle were taken. The pollen, at developmental stage in each anther, was examined using Acetocarmine dye. Pollens at the uninucleate to early binucleare stage were selected. Tillers having pollens at the above-mentioned stage were placed in a dark room at 25(±) 1 C and 16 hours photoperiod. When plantlets were obtained from these media, well-developed green plantlets were selected and planted in Yoshida solution to attain vigorous root growth. Diploid and haploid plants were formed from the anther culture method. At the heading stage, haploid plants were treated with colchicines to promote development into diploid plants. At maturity, plants produced from materials treated with different gamma doses were harvested separately. These homozygous lines were planted in the field and the characters were compared with their parents grown at the same time. The highest callus induction rate was found in materials treated with 450 Gy of gamma rays, but the lowest green plant regeneration rate was also observed at this dose. Among the forty-five homozygous lines obtained of the above materials, 7 lines, all from the 450 Gy gamma rays treated material, flowered earlier than the parents. One of the 7 early flowering lines, mutant line No 18, matured 19 days earlier but had the same yield as the parent. All other lines had a lower yield than the parent. Comparisons of yield and yield components of mutant line 18 and Yar-2 (parent) and comparison of quality characters are shown in tables

  7. Stimulation effects of γ-irradiation combined with colchicine on callus formation and green plant regeneration in rice anther culture

    International Nuclear Information System (INIS)

    Jin Wei; Chen Qiufang; Wang Cailian; Lu Yimei

    1999-09-01

    The ability of callus formation and green plant regeneration was very different for various rice types and varieties in rice anther culture. It was quite effective that rice anthers were irradiated with 10-40 Gy of γ-rays after 30 d incubation on induction medium and calli were treated on differentiation medium contained 10-75 mg/L of colchicine for increase of callus formation and green plant regeneration. Among these treatments, 10 Gy of γ-rats was the best for callus formation, and 20 Gy of γ-rays or 30 mg/L of colchicine was the most favourable for green plant regeneration. The simulation effect of 20 Gy of γ-irradiation combined with 30 mg/L of colchicine on green plant regeneration was much better than that of their separate use in rice anther culture

  8. Pretreatment Stress Enhances Embryogenic Callus Production in Anther Culture of Sturt’s Desert Pea (Swainsona formosa

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    ZULKARNAIN

    2007-03-01

    Full Text Available The aims of the experiment were to investigate the effect of pretreatment stress on the proliferation of anther-derived embryogenic callus, and its subsequent embryo regeneration in Swainsona formosa. Anthers were pretreated in starvation medium at cold (4 oC temperature and cultured. Cultures were initially placed in darkness for four weeks, followed by 16-h photoperiod at 25 + 1 oC. The stress pretreatment was found to enhance embryogenic callus formation on cultured anthers. Further, somatic embryos were successfully regenerated from embryogenic callus upon transferred onto regeneration medium supplemented with 1% sucrose and 4.63 M kinetin, and later plantlets were obtained. Meanwhile, nonembryogenic callus continued to grow resulting in more callus mass without showing any embryoid initiation.

  9. Tests of adaptation: functional studies of pollen removal and estimates of natural selection on anther position in wild radish.

    Science.gov (United States)

    Conner, Jeffrey K; Sahli, Heather F; Karoly, Keith

    2009-06-01

    There are a number of difficulties associated with the study of adaptation. One is a lack of variation in the trait, which is common in adaptations because past selection has removed unfit variants. This lack of variation makes it difficult to determine the relationship between trait variation and fitness. Another difficulty is proving causation in this trait-fitness relationship, because a correlated trait might be the actual adaptation. These difficulties can be ameliorated at least partially by combining studies of natural variation with studies of experimentally manipulated traits and traits whose variance has been augmented by artificial selection. We review here a number of our studies on the adaptive value of two aspects of anther position in wild radish (Raphanus raphanistrum, Brassicaceae): anther exsertion, i.e. the degree to which anthers protrude from the mouth of the corolla tube, and anther height dimorphism, i.e. the difference in lengths of the filaments between the two short and four long stamens. We have used both functional analyses, in which the response variable is pollen removal, and measurements of selection, in which the response variable is lifetime male fitness estimated by molecular genetic paternity analyses. In these studies we use both the natural variation in populations as well as manipulated variation, the latter through both stamen removal and artificial selection, to re-create the ancestral trait conditions. Our work provides convincing evidence that intermediate anther exsertion values are adaptive, and that this is probably an adaptation to a subset of the pollinator fauna, small bees. The picture for anther height dimorphism is much less clear, as the weight of current evidence suggests that current values of this trait might actually be maladaptive; however, if this is true it is difficult to understand how the dimorphism is maintained across the family Brassicaceae.

  10. Proteome analysis of the wild and YX-1 male sterile mutant anthers of wolfberry (Lycium barbarum L..

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    Rui Zheng

    Full Text Available Pollen development is disturbed in the early tetrad stage of the YX-1 male sterile mutant of wolfberry (Lycium barbarum L.. The present study aimed to identify differentially expressed anther proteins and to reveal their possible roles in pollen development and male sterility. To address this question, the proteomes of the wild-type (WT and YX-1 mutant were compared. Approximately 1760 protein spots on two-dimensional differential gel electrophoresis (2D-DIGE gels were detected. A number of proteins whose accumulation levels were altered in YX-1 compared with WT were identified by mass spectrometry and the NCBInr and Viridiplantae EST databases. Proteins down-regulated in YX-1 anthers include ascorbate peroxidase (APX, putative glutamine synthetase (GS, ATP synthase subunits, chalcone synthase (CHS, CHS-like, putative callose synthase catalytic subunit, cysteine protease, 5B protein, enoyl-ACP reductase, 14-3-3 protein and basic transcription factor 3 (BTF3. Meanwhile, activities of APX and GS, RNA expression levels of apx and atp synthase beta subunit were low in YX-1 anthers which correlated with the expression of male sterility. In addition, several carbohydrate metabolism-related and photosynthesis-related enzymes were also present at lower levels in the mutant anthers. In contrast, 26S proteasome regulatory subunits, cysteine protease inhibitor, putative S-phase Kinase association Protein 1(SKP1, and aspartic protease, were expressed at higher levels in YX-1 anthers relative to WT anthers. Regulation of wolfberry pollen development involves a complex network of differentially expressed genes. The present study lays the foundation for future investigations of gene function linked with wolfberry pollen development and male sterility.

  11. Ensuring Reproduction at High Temperatures: The Heat Stress Response during Anther and Pollen Development

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    Filomena Giorno

    2013-07-01

    Full Text Available Sexual reproduction in flowering plants is very sensitive to environmental stresses, particularly to thermal insults which frequently occur when plants grow in field conditions in the warm season. Although abnormalities in both male and female reproductive organs due to high temperatures have been described in several crops, the failure to set fruits has mainly been attributed to the high sensitivity of developing anthers and pollen grains, particularly at certain developmental stages. A global view of the molecular mechanisms involved in the response to high temperatures in the male reproductive organs will be presented in this review. In addition, transcriptome and proteomic data, currently available, will be discussed in the light of physiological and metabolic changes occurring during anther and pollen development. A deep understanding of the molecular mechanisms involved in the stress response to high temperatures in flowers and, particularly, in the male reproductive organs will be a major step towards development of effective breeding strategies for high and stable production in crop plants.

  12. Expressed sequences tags of the anther smut fungus, Microbotryum violaceum, identify mating and pathogenicity genes

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    Devier Benjamin

    2007-08-01

    Full Text Available Abstract Background The basidiomycete fungus Microbotryum violaceum is responsible for the anther-smut disease in many plants of the Caryophyllaceae family and is a model in genetics and evolutionary biology. Infection is initiated by dikaryotic hyphae produced after the conjugation of two haploid sporidia of opposite mating type. This study describes M. violaceum ESTs corresponding to nuclear genes expressed during conjugation and early hyphal production. Results A normalized cDNA library generated 24,128 sequences, which were assembled into 7,765 unique genes; 25.2% of them displayed significant similarity to annotated proteins from other organisms, 74.3% a weak similarity to the same set of known proteins, and 0.5% were orphans. We identified putative pheromone receptors and genes that in other fungi are involved in the mating process. We also identified many sequences similar to genes known to be involved in pathogenicity in other fungi. The M. violaceum EST database, MICROBASE, is available on the Web and provides access to the sequences, assembled contigs, annotations and programs to compare similarities against MICROBASE. Conclusion This study provides a basis for cloning the mating type locus, for further investigation of pathogenicity genes in the anther smut fungi, and for comparative genomics.

  13. Anther-preferential expressing gene PMR is essential for the mitosis of pollen development in rice.

    Science.gov (United States)

    Liu, Yaqin; Xu, Ya; Ling, Sheng; Liu, Shasha; Yao, Jialing

    2017-06-01

    Phenotype identification, expression examination, and function prediction declared that the anther-preferential expressing gene PMR may participate in regulation of male gametophyte development in rice. Male germline development in flowering plants produces the pair of sperm cells for double fertilization and the pollen mitosis is a key process of it. Although the structural features of male gametophyte have been defined, the molecular mechanisms regulating the mitotic cell cycle are not well elucidated in rice. Here, we reported an anther-preferential expressing gene in rice, PMR (Pollen Mitosis Relative), playing an essential role in male gametogenesis. When PMR gene was suppressed via RNAi, the mitosis of microspore was severely damaged, and the plants formed unmatured pollens containing only one or two nucleuses at the anthesis, ultimately leading to serious reduction of pollen fertility and seed-setting. The CRISPR mutants, pmr-1 and pmr-2, both showed the similar defects as the PMR-RNAi lines. Further analysis revealed that PMR together with its co-expressing genes were liable to participate in the regulation of DNA metabolism in the nucleus, and affected the activities of some enzymes related to the cell cycle. We finally discussed that unknown protein PMR contained the PHD, SWIB and Plus-3 domains and they might have coordinating functions in regulation pathway of the pollen mitosis in rice.

  14. Functional monoecy due to delayed anther dehiscence: a novel mechanism in Pseuduvaria mulgraveana (Annonaceae.

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    Chun-Chiu Pang

    Full Text Available Unlike most genera in the early-divergent angiosperm family Annonaceae, Pseuduvaria exhibits a diversity of floral sex expression. Most species are structurally andromonoecious (or possibly androdioecious, although the hermaphroditic flowers have been inferred to be functionally pistillate, with sterile staminodes. Pseuduvaria presents an ideal model for investigating the evolution of floral sex in early-divergent angiosperms, although detailed empirical studies are currently lacking. The phenology and pollination ecology of the Australian endemic species Pseuduvaria mulgraveana are studied in detail, including evaluations of floral scent chemistry, pollen viability, and floral visitors. Results showed that the flowers are pollinated by small diurnal nitidulid beetles and are protogynous. Pollen from both hermaphroditic and staminate flowers are shown to be equally viable. The structurally hermaphroditic flowers are nevertheless functionally pistillate as anther dehiscence is delayed until after petal abscission and hence after the departure of pollinators. This mechanism to achieve functional unisexuality of flowers has not previously been reported in angiosperms. It is known that protogyny is widespread amongst early-divergent angiosperms, including the Annonaceae, and is effective in preventing autogamy. Delayed anther dehiscence represents a further elaboration of this, and is effective in preventing geitonogamy since very few sexually mature flowers occur simultaneously in an individual. We highlight the necessity for field-based empirical interpretations of functional floral sex expression prior to evaluations of evolutionary processes.

  15. Functional monoecy due to delayed anther dehiscence: a novel mechanism in Pseuduvaria mulgraveana (Annonaceae).

    Science.gov (United States)

    Pang, Chun-Chiu; Scharaschkin, Tanya; Su, Yvonne C F; Saunders, Richard M K

    2013-01-01

    Unlike most genera in the early-divergent angiosperm family Annonaceae, Pseuduvaria exhibits a diversity of floral sex expression. Most species are structurally andromonoecious (or possibly androdioecious), although the hermaphroditic flowers have been inferred to be functionally pistillate, with sterile staminodes. Pseuduvaria presents an ideal model for investigating the evolution of floral sex in early-divergent angiosperms, although detailed empirical studies are currently lacking. The phenology and pollination ecology of the Australian endemic species Pseuduvaria mulgraveana are studied in detail, including evaluations of floral scent chemistry, pollen viability, and floral visitors. Results showed that the flowers are pollinated by small diurnal nitidulid beetles and are protogynous. Pollen from both hermaphroditic and staminate flowers are shown to be equally viable. The structurally hermaphroditic flowers are nevertheless functionally pistillate as anther dehiscence is delayed until after petal abscission and hence after the departure of pollinators. This mechanism to achieve functional unisexuality of flowers has not previously been reported in angiosperms. It is known that protogyny is widespread amongst early-divergent angiosperms, including the Annonaceae, and is effective in preventing autogamy. Delayed anther dehiscence represents a further elaboration of this, and is effective in preventing geitonogamy since very few sexually mature flowers occur simultaneously in an individual. We highlight the necessity for field-based empirical interpretations of functional floral sex expression prior to evaluations of evolutionary processes.

  16. Defective Pollen Wall is Required for Anther and Microspore Development in Rice and Encodes a Fatty Acyl Carrier Protein Reductase

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    Shi, J.; Shanklin, J.; Tan, H.; Yu, X.-H.; Liu, Y.; Liang, W.; Ranathunge, K.; Franke, R. B.; Schreiber, L.; Wang, Y.; Kai, G.; Ma, H.; Zhang, D.

    2011-06-01

    Aliphatic alcohols naturally exist in many organisms as important cellular components; however, their roles in extracellular polymer biosynthesis are poorly defined. We report here the isolation and characterization of a rice (Oryza sativa) male-sterile mutant, defective pollen wall (dpw), which displays defective anther development and degenerated pollen grains with an irregular exine. Chemical analysis revealed that dpw anthers had a dramatic reduction in cutin monomers and an altered composition of cuticular wax, as well as soluble fatty acids and alcohols. Using map-based cloning, we identified the DPW gene, which is expressed in both tapetal cells and microspores during anther development. Biochemical analysis of the recombinant DPW enzyme shows that it is a novel fatty acid reductase that produces 1-hexadecanol and exhibits >270-fold higher specificity for palmiltoyl-acyl carrier protein than for C16:0 CoA substrates. DPW was predominantly targeted to plastids mediated by its N-terminal transit peptide. Moreover, we demonstrate that the monocot DPW from rice complements the dicot Arabidopsis thaliana male sterile2 (ms2) mutant and is the probable ortholog of MS2. These data suggest that DPWs participate in a conserved step in primary fatty alcohol synthesis for anther cuticle and pollen sporopollenin biosynthesis in monocots and dicots.

  17. Influence of genotype, growth regulators, sucrose level and preconditioning of donor plants on flax (Linum usitatissimum L.) anther culture.

    Science.gov (United States)

    Burbulis, Natalija; Blinstrubiene, Ausra; Sliesaravicius, A; Venskutoniene, Egidija

    2005-01-01

    The effect of genotype, growth regulators and preconditioning of donor plants on callus induction in anther culture of flax was investigated. Anthers were cultured on modified MS medium supplemented with five different combinations of plant growth regulators. The results suggested that specific combinations of growth regulators must be designed for each genotype. Major differences between the present results and previous reports are discussed. The influence of sucrose concentration was also investigated. For flax cultivar, 'Mikael', callus induction was higher in medium supplemented with 1 mg l(-1) BAP and 2 mg l(-1) 2,4D containing 6% sucrose, while this combination of growth regulators significantly increased callogenesis in cultivars 'Lirina', 'Barbara' and 'Szaphir' when supplemented with 9% or 12% sucrose. The preconditioning of donor plants influenced callogenesis in subsequently isolated anthers. Anthers from donor plants grown at a lower temperature (18/14 degrees C) significantly increased callus induction over those from plants grown at a higher temperature (22/18 degrees C), although each genotype still required optimization of growth regulator combinations in the induction medium. Only 'Mikael' regenerated shoots when the callus was from induction medium supplemented with 2 mg I(-1) BAP and 1 mg l(-1) NAA.

  18. Anther-stigma separation is associated with inbreeding depression in Datura stramonium, a predominantly self-fertilizing annual.

    Science.gov (United States)

    Stone, Judy L; Motten, Alexander F

    2002-11-01

    Genetically based variation in outcrossing rate generates lineages within populations that differ in their history of inbreeding. According to some models, mating-system modifiers in such populations will demonstrate both linkage and identity disequilibrium with fitness loci, resulting in lineage-specific inbreeding depression. Other models assert that differences among families in levels of inbreeding depression are mainly attributable to random accumulation of genetic load, unrelated to variation at mating-system loci. We measured female reproductive success of selfed and outcrossed progeny from naturally occurring lineages of Datura stramonium, a predominantly self-fertilizing annual weed that has heritable variation in stigma-anther separation, a trait that influences selfing rates. Progeny from inbred lineages (as identified by high degree of anther-stigma overlap) showed equal levels of seed production, regardless of cross type. Progeny from mixed lineages (as identified by relatively high separation between anthers and stigma) showed moderate levels of inbreeding depression. We found a significant correlation between anther-stigma separation and relative fitness of selfed and outcrossed progeny, suggesting that family-level inbreeding depression may be related to differences among lineages in inbreeding history in this population. Negative inbreeding depression in putatively inbred lineages may be due in part to additive effects or to epistatic interactions among loci.

  19. Efficient transformation of Kalanchoe blossfeldiana and production of male-sterile plants by engineered anther ablation.

    Science.gov (United States)

    García-Sogo, Begoña; Pineda, Benito; Castelblanque, Lourdes; Antón, Teresa; Medina, Mónica; Roque, Edelín; Torresi, Claudia; Beltrán, José Pío; Moreno, Vicente; Cañas, Luis Antonio

    2010-01-01

    Engineered male sterility in ornamental plants has many applications such as facilitate hybrid seed production, eliminate pollen allergens, reduce the need for deadheading to extend the flowering period, redirect resources from seeds to vegetative growth, increase flower longevity and prevent gene flow between genetically modified and related native plants. We have developed a reliable and efficient Agrobacterium-mediated protocol for the genetic transformation of different Kalanchoe blossfeldiana commercial cultivars. Transformation efficiency for cv. 'Hillary' was 55.3% whereas that of cv. 'Tenorio' reached 75.8%. Selection was carried out with the nptII gene and increasing the kanamycin concentration from 25 to 100 mg l(-1) allowed to reduced escapes from 50 to 60% to virtually 0%. This method was used to produce male-sterile plants through engineered anther ablation. In our approach, we tested a male sterility chimaeric gene construct (PsEND1::barnase) to evaluate its effectiveness and effect on phenotype. No significant differences were found in the growth patterns between the transgenic lines and the wild-type plants. No viable pollen grains were observed in the ablated anthers of any of the lines carrying the PsEND1::barnase construct, indicating that the male sterility was complete. In addition, seed set was completely abolished in all the transgenic plants obtained. Our engineered male-sterile approach could be used, alone or in combination with a female-sterility system, to reduce the invasive potential of new ornamentals, which has become an important environmental problem in many countries.

  20. Down-Regulation of OsEMF2b Caused Semi-sterility Due to Anther and Pollen Development Defects in Rice

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    Luchang Deng

    2017-11-01

    Full Text Available Anther and pollen development are crucial processes of plant male reproduction. Although a number of genes involved in these processes have been identified, the regulatory networks of pollen and anther development are still unclear. EMBRYONIC FLOWER 2b (OsEMF2b is important for rice development. Its biological function in floral organ, flowering time and meristem determinacy have been well-studied, but its role, if only, on male reproduction is still unknown, because null mutants of OsEMF2b barely have anthers. In this study, we identified a weak allele of OsEMF2b, osemf2b-4. The T-DNA insertion was located in the promoter region of OsEMF2b, and OsEMF2b expression was significantly decreased in osemf2b-4. The osemf2b-4 mutant exhibited much more normal anthers than null mutants of OsEMF2b, and also showed defective floret development similar to null mutants. Cytological analysis showed various defects of anther wall and pollen development in osemf2b-4, such as slightly or extremely enlarged tapetum, irregular or normal morphology microspores, and partial or complete sterility. OsEMF2b was highly expressed in tapetum and microspores, and the protein was localized in the nucleus. The expression of 15 genes essential for anther and pollen development was investigated in both WT and osemf2b-4. Fourteen genes including GAMYB was up-regulated, and only PTC1 was down-regulated in osemf2b-4. This suggests that up-regulated GAMYB and down-regulated PTC1 might contribute to the defective anther and pollen development in osemf2b-4. Overall, our work suggests that OsEMF2b plays an essential role during post-meiotic anther and pollen development.

  1. Involvement of CAT in the detoxification of HT-induced ROS burst in rice anther and its relation to pollen fertility.

    Science.gov (United States)

    Zhao, Qian; Zhou, Lujian; Liu, Jianchao; Cao, Zhenzhen; Du, Xiaoxia; Huang, Fudeng; Pan, Gang; Cheng, Fangmin

    2018-05-01

    HT-induced ROS burst in developing anther is closely related to the lowered CAT activity as the result of the markedly suppressed OsCATB transcript, thereby causing severe fertility injury for rice plants exposed to HT at meiosis stage. The reproductive stage of rice plants is highly sensitive to heat stress. In this paper, different rice cultivars were used to investigate the relationship of HT-induced floret sterility with reactive oxygen species (ROS) detoxification in rice anthers under well-controlled climatic conditions. Results showed that high temperature (HT) exposure significantly enhanced the ROS level and malondialdehyde (MDA) content in developing anther, and the increase in ROS amount in rice anther under HT exposure was closely associated with HT-induced decline in the activities of several antioxidant enzymes. For various antioxidant enzymes, SOD and CAT were more susceptible to the ROS burst in rice anther induced by HT exposure than APX and POD, in which SOD and CAT activity in developing anther decreased significantly by HT exposure, whereas APX activity was relatively stable among different temperature regimes. HT-induced decrease in CAT activity was attributable to the suppressed transcript of OsCATB. This occurrence was strongly responsible for HT-induced increase in ROS level and oxidative-damage in rice anther, thereby it finally caused significant reduction in pollen viability and floret fertility for the rice plants exposed to HT during meiosis. Exogenous application of 1000 µM salicylic acid (SA) may alleviate HT-induced reduction in pollen viability and floret fertility, concomitantly with the increased CAT activity and reduced ROS level in rice anther.

  2. Effect of 60Co γ-rays irradiation pretreatment on callus inductivity and differentiation of strawberry anther

    International Nuclear Information System (INIS)

    Zhang Huiqin; Xie Ming; Jiang Guihua; Sun Congbo; Huang Pule; Wu Yanjun; Wu Qing

    2007-01-01

    Strawberry buds, in which a majority of pollen had single nuclear keeping to the side, were pretreated by 60 Co γ-rays irradiation at different doses. The irradiation effect on the callus inductivity and plant differentiation rate of strawberry anther were studied. The results indicated that the pretreatment by 60 Co γ-rays could increase the anther callus inductivity and plant differentiation rate significantly, and 20 Gy was the best dose. The callus inductivity of Akihime and Toyonoka increased by 39.09% and 35.68%, respectively, compared with the no-pretreatment materials. On the same media, the plant differentiation rate of Akihime and Toyonoka were also increased by 6.67%-6.72% and 4.73%-6.45%, respectively, compared with the two varieties of no-pretreatment. (authors)

  3. Embryogenesis induction, callogenesis, and plant regeneration by in vitro culture of tomato isolated microspores and whole anthers.

    Science.gov (United States)

    Seguí-Simarro, José M; Nuez, Fernando

    2007-01-01

    In this work, some of the different in vitro developmental pathways into which tomato microspores or microsporocytes can be deviated experimentally were explored. The two principal ones are direct embryogenesis from isolated microspores and callus formation from meiocyte-containing anthers. By means of light and electron microscopy, the process of early embryogenesis from isolated microspores and the disruption of normal meiotic development and change of developmental fate towards callus proliferation, morphogenesis, and plant regeneration have been shown. From microspores isolated at the vacuolate stage, embryos can be directly induced, thus avoiding non-androgenic products. In contrast, several different morphogenic events can be triggered in cultures of microsporocyte-containing anthers under adequate conditions, including indirect embryogenesis, adventitious organogenesis, and plant regeneration. Both callus and regenerated plants may be haploid, diploid, and mostly mixoploid. The results demonstrate that both gametophytic and sporophytic calli occur in cultured tomato anthers, and point to an in vitro-induced disturbance of cytokinesis and subsequent fusion of daughter nuclei as a putative cause for mixoploidy and genome doubling during both tetrad compartmentalization and callus proliferation. The potential implications of the different alternative pathways are discussed in the context of their application to the production of doubled-haploid plants in tomato, which is still very poorly developed.

  4. Haploid plant regeneration from anther cultures of three north american cultivars of strawberry (Fragaria x ananassa Duch.).

    Science.gov (United States)

    Owen, H R; Miller, A R

    1996-09-01

    A study was conducted to maximize plant regeneration frequencies from cultured anthers of 'Chandler', 'Honeoye', and 'Redchief' strawberries (Fragaria x ananassa Duch.). A comparison of auxins (IAA, NAA), cytokinins (BA, BPA, KIN) and carbohydrates (sucrose, glucose, maltose) in MS medium showed that the highest shoot regeneration across cultivars (8%) occurred when using a medium containing 2 mg/l IAA, 1 mg/l BA, and 0.2 M glucose. A comparison of MS, NN, and H1 inorganic medium (a new formulation based on the anther culture literature) solidified with either agar or gellan gum and containing IAA, BA, and glucose, showed the highest shoot regeneration across cultivars (19%) when using H1 and gellan gum. Lastly, media containing Fe-EDTA yielded more shoots than media containing Fe-Metalosate, and anthers cultured on Fe-EDTA media in darkness for 30d followed by 30d in white light produced more shoots (16% average regeneration) than those cultured on Fe-EDTA media under white or yellow light (16h photoperiod) for the initial 30d (0.3% and 5% respectively). Plants were acclimated ex vitro where they flowered and set fruit. Chromosome counts of root tip cells confirmed that haploid plants were obtained from all three cultivars.

  5. Development of embryoids by microspore and anther cultures of red beet (Beta vulgaris L. subsp. vulgaris

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    Krystyna GÓRECKA

    2017-03-01

    Full Text Available So far there is no information about receiving red beet androgenic embryos by androgenesis. Several factors were tested which affected this process: starch accumulation in microspores, correlation between bud length and microsporogenesis course, induction and regeneration medium composition. Ploidy level of obtained regenerants were evaluated. Treating anthers with α-amylase or watering donor plants with gibberellin increased number of obtained androgenic embryos. The highest percentage (80% of microspores at uninuclear stage appeared in buds with 1.3-1.5 mm. The B5 medium with 100 g·L-1 sucrose and 0.1 mg·L-1 2,4-D (2, 4-dichlorophenoxyacetic acid proved to be better for inducing androgenesis than MS medium supplemented with 0.2 mg·L-1 BAP (6-benzylaminopurine and 0.5 mg·L-1 IAA (indole-3-acetic acid. First androgenic embryos were placed on B5 medium without plant growth regulators and then on MS medium containing 0.2 mg·L-1 BAP and 1 mg·L-1 NAA (α-naphthaleneacetic acid. Androgenic embryos died on B5 regeneration medium without plant growth regulators. On MS medium first shoots and callus with and without roots were obtained. Rosettes withered during following passages whereas callus tissue developed further. The quantity of DNA in this tissue equivalent to 4X chromosomes.

  6. Identification of the tapetum/microspore-specific promoter of the pathogenesis-related 10 gene and its regulation in the anther of Lilium longiflorum.

    Science.gov (United States)

    Hsu, Ssu-Wei; Liu, Ming-Che; Zen, Kuo-Chang; Wang, Co-Shine

    2014-02-01

    A tapetum/microspore-specific pathogenesis-related (PR) 10 gene was previously identified in lily (Lilium longiflorum Thunb.) anthers. In situ hybridization and RNA blot analysis indicated that the lily PR10 genes are expressed specifically and differentially in the tapetum of the anther wall and in microspores during anther development. The accumulation of PR10 transcripts was exogenously induced by gibberellic acid (GA) and was suppressed by ethylene. Studies using inhibitors of GA and ethylene revealed that the lily PR10 is modulated by an antagonistic interaction between GA and ethylene. The treatment of norbornadien, an ethylene inhibitor, caused the tapetum to become densely cytoplasmic and highly polarized, whereas uniconazole, an inhibitor of GA biosynthesis, arrested tapetal development to a status close to that of control. The expression of the lily PR10g promoter in transgenic Arabidopsis was determined using the β-glucuronidase (GUS) reporter gene indicated that the decisive fragment required for anther specificity is located -1183 bp to -880 bp upstream of the transcription start site. The PR10gPro::barnase transgenic lines exhibited complete male sterility because of the disruption of the tapetum and the deformation of microspore/pollen. The anther specificity of lily PR10 highlights the importance of the tapetum/microspore-specific PR10g promoter for future biotechnological and agricultural applications. Copyright © 2013. Published by Elsevier Ireland Ltd.

  7. iTRAQ-facilitated proteomic profiling of anthers from a photosensitive male sterile mutant and wild-type cotton (Gossypium hirsutum L.).

    Science.gov (United States)

    Liu, Ji; Pang, Chaoyou; Wei, Hengling; Song, Meizhen; Meng, Yanyan; Ma, Jianhui; Fan, Shuli; Yu, Shuxun

    2015-08-03

    Male sterility is a common phenomenon in flowering plants, and it has been successfully developed in several crops by taking advantage of heterosis. Cotton (Gossypium hirsutum L.) is an important economic crop, used mainly for the production of textile fiber. Using a space mutation breeding technique, a novel photosensitive genetic male sterile mutant CCRI9106 was isolated from the wild-type upland cotton cultivar CCRI040029. To use CCRI9106 in cotton hybrid breeding, it is of great importance to study the molecular mechanisms of its male sterility. Here, histological and iTRAQ-facilitated proteomic analyses of anthers were performed to explore male sterility mechanisms of the mutant. Scanning and transmission electron microscopy of the anthers showed that the development of pollen wall in CCRI9106 was severely defective with a lack of exine formation. At the protein level, 6121 high-confidence proteins were identified and 325 of them showed differential expression patterns between mutant and wild-type anthers. The proteins up- or down-regulated in MT anthers were mainly involved in exine formation, protein degradation, calcium ion binding,etc. These findings provide valuable information on the proteins involved in anther and pollen development, and contribute to elucidate the mechanism of male sterility in upland cotton. Copyright © 2015. Published by Elsevier B.V.

  8. Evaluation of gelling agents on anther culture: response of two soybean cultivars

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    Milena Barcelos Cardoso

    2007-11-01

    Full Text Available Anthers of two soybean cultivars were cultured in B5 long basal culture media gelled with agarose or PhytagelTM. Cytological examinations of the anthers were carried out during the first 45 days of culture to assay the viability and developmental stage of microspores. Frequency of callus formation was recorded at 45 days of culture. The analysis of variance of the microspore viability assay showed significant Cultivar X Gelling Agent X Day of Culture interactions. The frequencies of viable microspores decreased significantly with time of culture, within each cultivar and gelling agent tested. The interaction Day X Cultivar was significant for the frequencies of binucleate symmetrical grains and multinucleate/multicellular structures. The effect of gelling agents on the frequency of binucleate symmetrical pollens grains and multinucleate/multicellular structures was not significant. About the frequencies of calli and embryogenic calli formed, a significant difference was detected between the cultivars (IAS5= 14.8% and BRS 133=6.6%. Gelling agents showed no effect over these frequencies.Anteras de duas cultivares de soja foram cultivadas em meio de cultura basal B5 longo gelificado com agarose ou Phytagel®. Análises citológicas das anteras foram conduzidas durante os primeiros 45 dias de cultura para avaliar a viabilidade e o estágio de desenvolvimento dos micrósporos. A freqüência de formação de calos foi analisada após 45 dias do início da cultura. A análise da variância da viabilidade do micrósporo mostrou interações significativas de Cultivar X Agente Gelificante X Dias de Cultura. As freqüências de grãos de pólen viáveis diminuíram significativamente com o tempo de cultura, dentro de cada cultivar e agente gelificante testado. A interação Dia X Cultivar foi significante para as freqüências de grãos de pólen binucleados simétricos e estruturas multinucleados/multicelulares. O efeito do agente gelificante na freq

  9. Multiple infections by the anther smut pathogen are frequent and involve related strains.

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    Manuela López-Villavicencio

    2007-11-01

    Full Text Available Population models of host-parasite interactions predict that when different parasite genotypes compete within a host for limited resources, those that exploit the host faster will be selected, leading to an increase in parasite virulence. When parasites sharing a host are related, however, kin selection should lead to more cooperative host exploitation that may involve slower rates of parasite reproduction. Despite their potential importance, studies that assess the prevalence of multiple genotype infections in natural populations remain rare, and studies quantifying the relatedness of parasites occurring together as natural multiple infections are particularly scarce. We investigated multiple infections in natural populations of the systemic fungal plant parasite Microbotryum violaceum, the anther smut of Caryophyllaceae, on its host, Silene latifolia. We found that multiple infections can be extremely frequent, with different fungal genotypes found in different stems of single plants. Multiple infections involved parasite genotypes more closely related than would be expected based upon their genetic diversity or due to spatial substructuring within the parasite populations. Together with previous sequential inoculation experiments, our results suggest that M. violaceum actively excludes divergent competitors while tolerating closely related genotypes. Such an exclusion mechanism might explain why multiple infections were less frequent in populations with the highest genetic diversity, which is at odds with intuitive expectations. Thus, these results demonstrate that genetic diversity can influence the prevalence of multiple infections in nature, which will have important consequences for their optimal levels of virulence. Measuring the occurrence of multiple infections and the relatedness among parasites within hosts in natural populations may be important for understanding the evolutionary dynamics of disease, the consequences of vaccine use

  10. Cultivate in vitro of wheat Anthers (Triticum Aestivum L.) In the ICA-TENZA and PAV -76 varieties

    International Nuclear Information System (INIS)

    Manrique O, Olga L.

    1994-01-01

    The objective of the present work consisted, in determining the cultivation conditions under which it was possible to induce through the technique of the cultivation of anthers, the callus formation and possible regeneration of green plants of wheat (Triticum aestivum L.) in the varieties ICA-Tenza and Pav -76. With the purpose of identifying the but appropriate state of development of the grain of pollen for the inoculation of the anthers, a cytologic study was made in which was correlation among the moriolic parameters of the plant; (inter liguler distances, auricle-knot distances and longitude of the edges) and the state of development of the microspore; Of the parameters, it was recommended to keep in mind the longitude from the edges when harvesting the experimental material. The anthers of both genotypes were inoculated in the means bases Pope 4 and N6, with hormonal levels of ELL (naftalen acetic acid) of 0.0, 0.5 and 1.0 mg/I. the answers of the genotypes were evaluated before the means of basal cultivation, in connection with the induction of tripes and the plants regeneration. Of the two used genotypes, the Pav -76 it presented bigger capacity to induce the formation of tripes, while the ICA-Tenza genotype presented a bigger answer capacity in the regeneration of plants so much green as albino. The results obtained allowed to establish that a relationship exists between the means of cultivation and the capacity of the genotypes to regenerate as much tripes as plants. Due to the drop survival of the regenerated plants, it was not possible to settle down with clarity a relationship of the ploidia level

  11. Recovery of Green Plantlets from Albino Shoot Primordia Derived from Anther Culture of Indica Rice (Oryza sativa L.)

    OpenAIRE

    Mohiuddin, Abul Kashem Md.; Karim, Nilufer Hye; Sultana, Shahanaz; Ferdous, Zannatul

    2011-01-01

    A simple method was developed to permit albino plant regeneration from anther culture of Hobigonj Boro (Hbj B) IV and Hbj B VI, two local varieties of aromatic indica rice from Bangladesh. Three crucial factors were identified for the albino shoot primordia to change into green plantlets in culture; components of M10 induction medium, callus size (range 0.2–0.4 cm long) and height of shoot primordia (range 2–3 mm). Immediate transfer of shoot primordia (2–3 mm) from M10 medium to regeneration...

  12. Comparative Analysis of Anther Transcriptome Profiles of Two Different Rice Male Sterile Lines Genotypes under Cold Stress

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    Bin Bai

    2015-05-01

    Full Text Available Rice is highly sensitive to cold stress during reproductive developmental stages, and little is known about the mechanisms of cold responses in rice anther. Using the HiSeq™ 2000 sequencing platform, the anther transcriptome of photo thermo sensitive genic male sterile lines (PTGMS rice Y58S and P64S (Pei’ai64S were analyzed at the fertility sensitive stage under cold stress. Approximately 243 million clean reads were obtained from four libraries and aligned against the oryza indica genome and 1497 and 5652 differentially expressed genes (DEGs were identified in P64S and Y58S, respectively. Both gene ontology (GO and Kyoto Encyclopedia of Genes and Genomes (KEGG analyses were conducted for these DEGs. Functional classification of DEGs was also carried out. The DEGs common to both genotypes were mainly involved in signal transduction, metabolism, transport, and transcriptional regulation. Most of the DEGs were unique for each comparison group. We observed that there were more differentially expressed MYB (Myeloblastosis and zinc finger family transcription factors and signal transduction components such as calmodulin/calcium dependent protein kinases in the Y58S comparison group. It was also found that ribosome-related DEGs may play key roles in cold stress signal transduction. These results presented here would be particularly useful for further studies on investigating the molecular mechanisms of rice responses to cold stress.

  13. Microspores irradiation in anther culture: testing a new technique to obtain mutations immediatly detected and fixed (Application to Nicotiana tabacum)

    International Nuclear Information System (INIS)

    Mondeil, Fanja

    1974-01-01

    In order to consider the effects of microspores irradiation on embryo development, and in order to observe the morphological responses of haploid plantlets derived from androgenetic anthers to ionizing irradiation, 1000, 1500 and 2000r of gamma rays were delivered on anthers of Nicotiana tabacum (DL 50 range calculated: 1500r). The cytological studies of embryo development revealed an apparent increase in irradiated microspores: cell division is stimulated but followed by an early mortality. A sharp rise in lethality effects was observed when gamma rays were applied beyond the seventh day of culture, when the proembryo contains an average of 4 cells. Morphological aberrations and colour changes in the Mo progeny derived from irradiated microspores are diverse. But after chromosome doubling and mutation checking out, all the plants were not recorded to have transmitted their aberrant characters. Thus, heritable character 'mutations) and not heritable character (variations) were obtained. The variations characters include dwarfing, excessive branching, fasciation and dichotomy of the stems, altered flower form, especially of petals. As to the leaves, they usually show induced changes in their colour (chlorotic areas, mosaic-colour changes, or an over-all colour changes), in their form (irregularity in outline) and in their texture (thickening, hairless leaf). Among the mutants, a monster tobacco, with excrescences on the leaves and the flowers is certainly the most conspicuous. But mutants also include altered leaf colour (over-all pale green) and altered flower colour, (dark red, clear pink, white) [fr

  14. Brassinosteroids promote development of rice pollen grains and seeds by triggering expression of Carbon Starved Anther, a MYB domain protein.

    Science.gov (United States)

    Zhu, Xiaolei; Liang, Wanqi; Cui, Xiao; Chen, Mingjiao; Yin, Changsong; Luo, Zhijing; Zhu, Jiaying; Lucas, William J; Wang, Zhiyong; Zhang, Dabing

    2015-05-01

    Transport of photoassimilates from leaf tissues (source regions) to the sink organs is essential for plant development. Here, we show that a phytohormone, the brassinosteroids (BRs) promotes pollen and seed development in rice by directly promoting expression of Carbon Starved Anther (CSA) which encodes a MYB domain protein. Over-expression of the BR-synthesis gene D11 or a BR-signaling factor OsBZR1 results in higher sugar accumulation in developing anthers and seeds, as well as higher grain yield compared with control non-transgenic plants. Conversely, knockdown of D11 or OsBZR1 expression causes defective pollen maturation and reduced seed size and weight, with less accumulation of starch in comparison with the control. Mechanically, OsBZR1 directly promotes CSA expression and CSA directly triggers expression of sugar partitioning and metabolic genes during pollen and seed development. These findings provide insight into how BRs enhance plant reproduction and grain yield in an important agricultural crop. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  15. Recovery of Green Plantlets from Albino Shoot Primordia Derived from Anther Culture of Indica Rice (Oryza sativa L.).

    Science.gov (United States)

    Mohiuddin, Abul Kashem Md; Karim, Nilufer Hye; Sultana, Shahanaz; Ferdous, Zannatul

    2011-05-01

    A simple method was developed to permit albino plant regeneration from anther culture of Hobigonj Boro (Hbj B) IV and Hbj B VI, two local varieties of aromatic indica rice from Bangladesh. Three crucial factors were identified for the albino shoot primordia to change into green plantlets in culture; components of M10 induction medium, callus size (range 0.2-0.4 cm long) and height of shoot primordia (range 2-3 mm). Immediate transfer of shoot primordia (2-3 mm) from M10 medium to regeneration medium followed by continuous incubation under fluorescent light (100-lux, 25±1°C) triggered albino shoot primordia to turn green in 2-3 days. Callus size did not show any effect on the change. Albino plantlets derived from anther callus cultured in KA, KB, KC, KD and KE media did not recover in both the varieties. Transfer of albino shoot primordia shorter or longer than 2-3 mm from the above 5 cultures to regeneration medium did not cause the shoot primordia to turn green. 100% albino shoot primordia initiated from Hbj B VI and 79% from Hbj B IV in M10 medium changed to green plantlets upon transfer to regeneration medium. Subsequent culture and subculture of green plantlets showed rapid formation of many new green plantlets.

  16. High-resolution fine mapping of ps-2, a mutated gene conferring functional male sterility in tomato due to non-dehiscent anthers

    NARCIS (Netherlands)

    Gorguet, B.J.M.; Schipper, E.H.; Heusden, van A.W.; Lindhout, P.

    2006-01-01

    Functional male sterility is an important trait for the production of hybrid seeds. Among the genes coding for functional male sterility in tomato is the positional sterility gene ps-2. ps-2 is monogenic recessive, confers non-dehiscent anthers and is the most suitable for practical uses. In order

  17. Intraspecific competition and mating between fungal strains of the anther smut Microbotryum violaceum from the host plants Silene latifolia and S-dioica

    NARCIS (Netherlands)

    Van Putten, WF; Biere, A; Van Damme, JMM

    We studied intraspecific competition and assortative mating between strains of the anther smut fungus Microbotryum violaceum from two of its host species, Silene latifolia and S. dioica. Specifically. we investigated whether strains from allopatric host populations have higher competitive ability on

  18. Intraspecific competition and mating between fungal strains of the anther smut Microbotryum violaceum from the host plants Silene latifolia and S-dioica.

    NARCIS (Netherlands)

    Van Putten, W.F.; Biere, A.; Van Damme, J.M.M.

    2003-01-01

    We studied intraspecific competition and assortative mating between strains of the anther smut fungus Microbotryum violaceum from two of its host species, Silene latifolia and S. dioica. Specifically, we investigated whether strains from allopatric host populations have higher competitive ability on

  19. The ASH1 HOMOLOG 2 (ASHH2 histone H3 methyltransferase is required for ovule and anther development in Arabidopsis.

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    Paul E Grini

    Full Text Available BACKGROUND: SET-domain proteins are histone lysine (K methyltransferases (HMTase implicated in defining transcriptionally permissive or repressive chromatin. The Arabidopsis ASH1 HOMOLOG 2 (ASHH2 protein (also called SDG8, EFS and CCR1 has been suggested to methylate H3K4 and/or H3K36 and is similar to Drosophila ASH1, a positive maintainer of gene expression, and yeast Set2, a H3K36 HMTase. Mutation of the ASHH2 gene has pleiotropic developmental effects. Here we focus on the role of ASHH2 in plant reproduction. METHODOLOGY/PRINCIPAL FINDINGS: A slightly reduced transmission of the ashh2 allele in reciprocal crosses implied involvement in gametogenesis or gamete function. However, the main requirement of ASHH2 is sporophytic. On the female side, close to 80% of mature ovules lack embryo sac. On the male side, anthers frequently develop without pollen sacs or with specific defects in the tapetum layer, resulting in reduction in the number of functional pollen per anther by up to approximately 90%. In consistence with the phenotypic findings, an ASHH2 promoter-reporter gene was expressed at the site of megaspore mother cell formation as well as tapetum layers and pollen. ashh2 mutations also result in homeotic changes in floral organ identity. Transcriptional profiling identified more than 300 up-regulated and 600 down-regulated genes in ashh2 mutant inflorescences, whereof the latter included genes involved in determination of floral organ identity, embryo sac and anther/pollen development. This was confirmed by real-time PCR. In the chromatin of such genes (AP1, AtDMC1 and MYB99 we observed a reduction of H3K36 trimethylation (me3, but not H3K4me3 or H3K36me2. CONCLUSIONS/SIGNIFICANCE: The severe distortion of reproductive organ development in ashh2 mutants, argues that ASHH2 is required for the correct expression of genes essential to reproductive development. The reduction in the ashh2 mutant of H3K36me3 on down-regulated genes relevant to

  20. Polyamine oxidase 7 is a terminal catabolism-type enzyme in Oryza sativa and is specifically expressed in anthers.

    Science.gov (United States)

    Liu, Taibo; Kim, Dong Wook; Niitsu, Masaru; Maeda, Shunsuke; Watanabe, Masao; Kamio, Yoshiyuki; Berberich, Thomas; Kusano, Tomonobu

    2014-06-01

    Polyamine oxidase (PAO), which requires FAD as a cofactor, functions in polyamine catabolism. Plant PAOs are classified into two groups based on their reaction modes. The terminal catabolism (TC) reaction always produces 1,3-diaminopropane (DAP), H2O2, and the respective aldehydes, while the back-conversion (BC) reaction produces spermidine (Spd) from tetraamines, spermine (Spm) and thermospermine (T-Spm) and/or putrescine from Spd, along with 3-aminopropanal and H2O2. The Oryza sativa genome contains seven PAO-encoded genes termed OsPAO1-OsPAO7. To date, we have characterized four OsPAO genes. The products of these genes, i.e. OsPAO1, OsPAO3, OsPAO4 and OsPAO5, catalyze BC-type reactions. Whereas OsPAO1 remains in the cytoplasm, the other three PAOs localize to peroxisomes. Here, we examined OsPAO7 and its gene product. OsPAO7 shows high identity to maize ZmPAO1, the best characterized plant PAO having TC-type activity. OsPAO7 seems to remain in a peripheral layer of the plant cell with the aid of its predicted signal peptide and transmembrane domain. Recombinant OsPAO7 prefers Spm and Spd as substrates, and it produces DAP from both substrates in a time-dependent manner, indicating that OsPAO7 is the first TC-type enzyme identified in O. sativa. The results clearly show that two types of PAOs co-exist in O. sativa. Furthermore, OsPAO7 is specifically expressed in anthers, with an expressional peak at the bicellular pollen stage. The physiological function of OsPAO7 in anthers is discussed. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  1. Effect of ovary induction on bread wheat anther culture: ovary genotype and developmental stage, and candidate gene association.

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    Ana María Castillo

    2015-06-01

    Full Text Available Ovary pre-conditioned medium and ovary co-culture increased the efficiency of green doubled haploid plant production in bread wheat anther culture. The positive effect of this medium led to a 6- and 11-fold increase in the numbers of embryos and green plants, respectively, having a greater effect on a medium-low responding cultivar. Ovary genotype and developmental stage significantly affected microspore embryogenesis. By he use of Caramba ovaries it was possible to reach a 2-fold increase in the number of embryos and green plants, and to decrease the rate of albinism. Mature ovaries from flowers containing microspores at a late binucleate stage raised the number of embryos and green plants by 25% and 46% as compared to immature ovaries (excised from flowers with microspores at a mid-late uninucleate stage. The highest numbers of embryos and green plants were produced when using mature Caramba ovaries. Ovaries from Galeón, Tigre and Kilopondio cultivars successfully induced microspore embryogenesis at the same rate as Caramba ovaries. Moreover, Tigre ovaries raised the percentage of spontaneous chromosome doubling up to 71%. Attempts were made to identify molecular mechanisms associated to the inductive effect of the ovaries on microspore embryogenesis. The genes TAA1b, FLA26 and WALI6 associated to wheat microspore embryogenesis, the CGL1 gene involved in glycan biosynthesis or degradation, and the FER gene involved in the ovary signalling process were expressed and/or induced at different rates during ovary culture. The expression pattern of FLA26 and FER could be related to the differences between genotypes and developmental stages in the inductive effect of the ovary. Our results open opportunities for new approaches to increase bread wheat doubled haploid production by anther culture, and to identify the functional components of the ovary inductive effect on microspore embryogenesis.

  2. Calogênese in vitro em anteras de coffea arabica L. In vitro callogenesis in anthers of Coffea arabica L.

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    Ednamar Gabriela Palú

    2004-08-01

    Full Text Available O café é um dos mais importantes produtos do mercado internacional; porém, o tempo gasto e os recursos despendidos são fatores limitantes para o melhoramento do cafeeiro por meio de métodos convencionais. Contudo, a cultura de anteras surge como uma alternativa viável e de curto prazo para solução desses problemas. Com o presente trabalho, objetivou-se a produção de dihaplóides com a cultura de anteras do cafeeiro (androgênese indireta, buscando um protocolo para a fase de indução de calos. Para tanto, foi efetuada a assepsia dos botões florais e das anteras, que, em seguida, foram inoculadas em meio IC e mantidas no escuro por 8 semanas, sob temperatura de 25ºC ± 1. Para induzir a calogênese em anteras da cv. Acaiá Cerrado, foram testadas as concentrações de 2,4-D (0, 1, 2 e 4 mg.L-1 x cinetina (0, 2, 4 e 8 mg.L-1 e 2,4-D (0; 0,5; 1 e 2 mg.L-1 x AIB (0; 0,5; 1 e 2 mg.L-1 mais 2iP (2 mg.L-1 e, para a cv. Rubi, as concentrações de 2,4-D (0, 1, 2 e 4 mg.L-1 x cinetina (0, 2, 4 e 8 mg.L-1. Foi observado que a maior porcentagem de indução de calogênese em anteras na cv. Acaiá Cerrado ocorre com as combinações de 2,4-D (2 mg.L-1 + cinetina (1,9 mg.L-1 e 2,4-D (0,86 mg.L-1 + AIB (1 mg.L-1+ 2iP (2 mg.L-1; para cv. Rubi, a combinação de 2,4-D (1,9 mg.L-1 e cinetina (4 mg.L-1.The coffee is one of the most important products of the international market, however the time and money wasted in breeding programs are limiting factors for its improvement. However, the anther culture appears as a viable alternative for a short time period solution for this problem. This work aimed to obtain the double haploids production from anther cultures of the coffee plant (indirect androgenesis aiming to optimize a protocol calluse induction. For this purpose, asseptic conditions of the flower budsand anthers were accomplished, folowed by inoculationin IC medium and the tissue were kept for eight weeks at 25ºC ± 1 in the dark. To induce

  3. A milestone in the doubled haploid pathway of cassava: a milestone in the doubled haploid pathway of cassava (Manihot esculenta Crantz): cellular and molecular assessment of anther-derived structures.

    Science.gov (United States)

    Perera, P I P; Ordoñez, C A; Lopez-Lavalle, L A Becerra; Dedicova, B

    2014-01-01

    This study was aimed at inducing androgenesis in cultured anthers of cassava (Manihot esculenta Crantz) to develop a protocol for the production of doubled haploids. Microspore reprogramming was induced in cassava by cold or heat stress of anthers. Since the anthers contain both haploid microspores and diploid somatic cells, it was essential to verify the origin of anther-derived calli. The origin of anther-derived calli was assessed by morphological screening followed by histological analysis and flow cytometry (FCM). Additionally, simple sequence repeat (SSR) and amplified fragmented length polymorphism (AFLP) assays were used for the molecular identification of the microspore-derived calli. The study clearly demonstrated the feasibility of producing microspore-derived calli using heat- or cold-pretreated anthers. Histological studies revealed reprogramming of the developmental pathway of microspores by symmetrical division of the nucleus. Flow cytometry analysis revealed different ploidy level cell types including haploids, which confirmed their origin from the microspores. The SSR and AFLP marker assays independently confirmed the histological and FCM results of a haploid origin of the calli at the DNA level. The presence of multicellular microspores in the in vitro system indicated a switch of developmental program, which constitutes a crucial step in the design of protocols for the regeneration of microspore-derived embryos and plants. This is the first detailed report of calli, embryos, and abnormal shoots originated from the haploid cells in cassava, leading to the development of a protocol for the production of doubled haploid plants in cassava.

  4. Microsporogenesis in vivo and in vitro. Autofluorescence of pollen wall of Lilium and changes in pollen wall of Gasteria in Lilium anther

    OpenAIRE

    M. T. Willemse

    2014-01-01

    Autafluarescence of the pollen wall of Lilium shows a correlative change with its development. When the pollen of Gasteria is injected into the anther of Lilium, it exhibits almost the same characteristics of wall autofluorescence as those of Lilium. Only the last stages of wall development are dissimilar. During this period the pollenkitt sticks to the pollen wall in Lilium only. The conclusion is that in the exine of Gasteria pollen, in contact with the locular fluid of Lilium, polymerizati...

  5. Cyto-histological processes during the differentiation of the tapetal cells in the anthers of Anthemis tinctoria L., Erigeron annuus (L. Pers. and E. canadensis L.

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    K. Bijok

    2015-01-01

    Full Text Available Tapetal cells in the anthers of Anthemis tinctoria, Erigeron annus and E. canadensis were uninucleate in the premeiotic stage of the PMC's. Ta-petum differentiation with inhibited cytokinesis took place during the period of meiotic divisions. In E. canadensis both mitoses were normal, wheareas in A. tinctoria and E. canadensis after both first and second mitotic divisions as a result of numerous disturbances polyploid nuclei were formed.

  6. Overexpression of rice black-streaked dwarf virus p7-1 in Arabidopsis results in male sterility due to non-dehiscent anthers.

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    Feng Sun

    Full Text Available Rice black-streaked dwarf virus (RBSDV, a member of the genus Fijivirus in the family Reoviridae, is propagatively transmitted by the small brown planthopper (Laodelphax striatellus Fallén. RBSDV causes rice black-streaked dwarf and maize rough dwarf diseases, which lead to severe yield losses in crops in China. Although several RBSDV proteins have been studied in detail, the functions of the nonstructural protein P7-1 are still largely unknown. To investigate the role of the P7-1 protein in virus pathogenicity, transgenic Arabidopsis thaliana plants were generated in which the P7-1 gene was expressed under the control of the 35S promoter. The RBSDV P7-1-transgenic Arabidopsis plants (named P7-1-OE were male sterility. Flowers and pollen from P7-1-transgenic plants were of normal size and shape, and anthers developed to the normal size but failed to dehisce. The non-dehiscent anthers observed in P7-1-OE were attributed to decreased lignin content in the anthers. Furthermore, the reactive oxygen species levels were quite low in the transgenic plants compared with the wild type. These results indicate that ectopic expression of the RBSDV P7-1 protein in A. thaliana causes male sterility, possibly through the disruption of the lignin biosynthesis and H2O2-dependent polymerization pathways.

  7. Overexpression of rice black-streaked dwarf virus p7-1 in Arabidopsis results in male sterility due to non-dehiscent anthers.

    Science.gov (United States)

    Sun, Feng; Yuan, Xia; Xu, Qiufang; Zhou, Tong; Fan, Yongjian; Zhou, Yijun

    2013-01-01

    Rice black-streaked dwarf virus (RBSDV), a member of the genus Fijivirus in the family Reoviridae, is propagatively transmitted by the small brown planthopper (Laodelphax striatellus Fallén). RBSDV causes rice black-streaked dwarf and maize rough dwarf diseases, which lead to severe yield losses in crops in China. Although several RBSDV proteins have been studied in detail, the functions of the nonstructural protein P7-1 are still largely unknown. To investigate the role of the P7-1 protein in virus pathogenicity, transgenic Arabidopsis thaliana plants were generated in which the P7-1 gene was expressed under the control of the 35S promoter. The RBSDV P7-1-transgenic Arabidopsis plants (named P7-1-OE) were male sterility. Flowers and pollen from P7-1-transgenic plants were of normal size and shape, and anthers developed to the normal size but failed to dehisce. The non-dehiscent anthers observed in P7-1-OE were attributed to decreased lignin content in the anthers. Furthermore, the reactive oxygen species levels were quite low in the transgenic plants compared with the wild type. These results indicate that ectopic expression of the RBSDV P7-1 protein in A. thaliana causes male sterility, possibly through the disruption of the lignin biosynthesis and H2O2-dependent polymerization pathways.

  8. Global transcriptome analysis of two ameiotic1 alleles in maize anthers: defining steps in meiotic entry and progression through prophase I

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    Fernandes John F

    2011-08-01

    Full Text Available Abstract Background Developmental cues to start meiosis occur late in plants. Ameiotic1 (Am1 encodes a plant-specific nuclear protein (AM1 required for meiotic entry and progression through early prophase I. Pollen mother cells (PMCs remain mitotic in most am1 mutants including am1-489, while am1-praI permits meiotic entry but PMCs arrest at the leptotene/zygotene (L/Z transition, defining the roles of AM1 protein in two distinct steps of meiosis. To gain more insights into the roles of AM1 in the transcriptional pre-meiotic and meiotic programs, we report here an in depth analysis of gene expression alterations in carefully staged anthers at 1 mm (meiotic entry and 1.5 mm (L/Z caused by each of these am1 alleles. Results 1.0 mm and 1.5 mm anthers of am1-489 and am1-praI were profiled in comparison to fertile siblings on Agilent® 4 × 44 K microarrays. Both am1-489 and am1-praI anthers are cytologically normal at 1.0 mm and show moderate transcriptome alterations. At the 1.5-mm stage both mutants are aberrant cytologically, and show more drastic transcriptome changes. There are substantially more absolute On/Off and twice as many differentially expressed genes (sterile versus fertile in am1-489 than in am1-praI. At 1.5 mm a total of 4,418 genes are up- or down-regulated in either am1-489 or am1-praI anthers. These are predominantly stage-specific transcripts. Many putative meiosis-related genes were found among them including a small subset of allele-specific, mis-regulated genes specific to the PMCs. Nearly 60% of transcriptome changes in the set of transcripts mis-regulated in both mutants (N = 530 are enriched in PMCs, and only 1% are enriched in the tapetal cell transcriptome. All array data reported herein will be deposited and accessible at MaizeGDB http://www.maizegdb.org/. Conclusions Our analysis of anther transcriptome modulations by two distinct am1 alleles, am1-489 and am1-praI, redefines the role of AM1 as a modulator of expression

  9. Efeitos do estádio de desenvolvimento da antera e da radiação gama na formação de calos derivados de anteras de tomate Anther development stage and gamma radiation effects on tomato anther-derived callus formation

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    Ana Christina R. Brasileiro

    1999-10-01

    Full Text Available Este trabalho foi conduzido visando: (I determinar a influência do estádio de desenvolvimento de anteras de tomate sobre a formação de calos e (II analisar o efeito da radiação gama no cultivo in vitro de anteras. No primeiro experimento, anteras de híbridos de tomate IPA 5 x Rotam 4 (F1 foram cultivadas em três meios nutritivos. Apesar da formação de calos ter sido induzida em todos os estádios de desenvolvimento, variando de prófase I à micrósporo mononucleado, a freqüência de calos produzidos decresceu com o avanço do estádio de desenvolvimento e se apresentou de forma semelhante nos meios testados. Anteras contendo meiócitos em estádio de prófase I mostraram maior freqüência de formação de calos. Tanto o comprimento da antera quanto o do botão floral apresentaram correlação significativa com o estádio de desenvolvimento. No segundo experimento, sementes e botões florais dos híbridos IPA 5 x Rotam 4 (F2, IPA 6 x Rotam 4 (F2 e IPA 8 x 217.1 (F2 foram submetidos à radiação gama e suas anteras foram cultivadas em dois meios descritos por Gresshoff & Doy (1972, contendo 2,0 mg L-1 de ANA + 5,0 mg L-1 de cinetina e 2,0 mg L-1 de ANA + 1,0 mg L-1 de cinetina. Não foram constatadas diferenças significativas, no que se refere à formação de calos, para os genótipos e doses estudadas - 200 Gy, para sementes e 20 Gy, para botões florais.Two experiments were carried (I to determine tomato anther development stage influence on callus production; and (II to investigate gamma radiation effects on anther culture. In the first experiment, anthers of a tomato hybrid (IPA 5 x Rotam 4 - F1 were grown on three media. Although calli were induced at all stages of anther development, varying from prophase I to mononucleate microspore, callus frequency decreased as anther development progressed and calli induction were not significantly affected by all media tested. Anthers containing prophase I meiocytes produced the highest

  10. Anther development of maize (Zea mays) and longstamen rice (Oryza longistaminata) revealed by cryo-SEM, with foci on locular dehydration and pollen arrangement.

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    Tsou, Chih-Hua; Cheng, Ping-Chin; Tseng, Chiung-Maan; Yen, Hsiao-Jung; Fu, Yu-Lan; You, Tien-Rong; Walden, David B

    2015-03-01

    Key message: Pollen maturation in Poaceae. Another development has been extensively examined by various imaging tools, including transmission electron microscopy, scanning electron microscopy, and light microscopy, but none is capable of identifying liquid water. Cryo-scanning electron microscopy with high-pressure rapid freeze fixation is excellent in preserving structures at cellular level and differentiating gas- versus liquid-filled space, but rarely used in anther study. We applied this technique to examine anther development of Poaceae because of its economic importance and unusual peripheral arrangement of pollen. Maize and longstamen rice were focused on. Here, we report for the first time that anthers of Poaceae lose the locular free liquid during late-microspore to early pollen stages; the majority of pollen grains arranged in a tight peripheral whorl develops normally and reaches maturity in the gas-filled loculus. Occasionally, pollen grains are found situated in the locular cavity, but they remain immature or become shrunk at anthesis. At pollen stage, microchannels and cytoplasmic strands are densely distributed in the entire pollen exine and intine, respectively, suggesting that nutrients are transported into the pollen from the entire surface. We propose that in Poaceae, the specialized peripheral arrangement of pollen grains is crucial for pollen maturation in the gas-filled loculus, which enables pollen achieving large surface contact area with the tapetum and neighboring grains to maintain sufficient nutrient flow. This report also shows that the single aperture of pollen in Poaceae usually faces the tapetum, but other orientation is also common; pollen grains with different aperture orientations show no morphological differences.

  11. Microsporogenesis in vivo and in vitro. Autofluorescence of pollen wall of Lilium and changes in pollen wall of Gasteria in Lilium anther

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    M. T. Willemse

    2014-01-01

    Full Text Available Autafluarescence of the pollen wall of Lilium shows a correlative change with its development. When the pollen of Gasteria is injected into the anther of Lilium, it exhibits almost the same characteristics of wall autofluorescence as those of Lilium. Only the last stages of wall development are dissimilar. During this period the pollenkitt sticks to the pollen wall in Lilium only. The conclusion is that in the exine of Gasteria pollen, in contact with the locular fluid of Lilium, polymerization of Lilium sporapollenin occurs instead of a structural addition to the wall. This polymerization is a continuous process during the entire development.

  12. Temperature stress differentially modulates transcription in meiotic anthers of heat-tolerant and heat-sensitive tomato plants

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    Pezzotti Mario

    2011-07-01

    Full Text Available Abstract Background Fluctuations in temperature occur naturally during plant growth and reproduction. However, in the hot summers this variation may become stressful and damaging for the molecular mechanisms involved in proper cell growth, impairing thus plant development and particularly fruit-set in many crop plants. Tolerance to such a stress can be achieved by constitutive gene expression or by rapid changes in gene expression, which ultimately leads to protection against thermal damage. We have used cDNA-AFLP and microarray analyses to compare the early response of the tomato meiotic anther transcriptome to moderate heat stress conditions (32°C in a heat-tolerant and a heat-sensitive tomato genotype. In the light of the expected global temperature increases, elucidating such protective mechanisms and identifying candidate tolerance genes can be used to improve breeding strategies for crop tolerance to heat stress. Results The cDNA-AFLP analysis shows that 30 h of moderate heat stress (MHS alter the expression of approximately 1% of the studied transcript-derived fragments in a heat-sensitive genotype. The major effect is gene down-regulation after the first 2 h of stress. The microarray analysis subsequently applied to elucidate early responses of a heat-tolerant and a heat-sensitive tomato genotype, also shows about 1% of the genes having significant changes in expression after the 2 h of stress. The tolerant genotype not only reacts with moderate transcriptomic changes but also exhibits constitutively higher expression levels of genes involved in protection and thermotolerance. Conclusion In contrast to the heat-sensitive genotype, the heat-tolerant genotype exhibits moderate transcriptional changes under moderate heat stress. Moreover, the heat-tolerant genotype also shows a different constitutive gene expression profile compared to the heat-sensitive genotype, indicating genetic differences in adaptation to increased temperatures. In

  13. MS26/CYP704B is required for anther and pollen wall development in bread wheat (Triticum aestivum L. and combining mutations in all three homeologs causes male sterility.

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    Manjit Singh

    Full Text Available Development of anthers and pollen represents an important aspect of the life cycle in flowering plants. Genes contributing to anther and pollen development have been widely studied in many plant species. Ms26/CYP704B genes play an important role in pollen development through biosynthesis of sporopollenin for pollen exine formation. To investigate the role of Ms26/CYP704B genes in anther and pollen development of bread wheat, mutations in the A-, B-, and D-homeologs of the putative Ms26/CYP704B gene were analyzed. Single and double homozygous mutants in any of the homeologs did not affect pollen development and male fertility. Triple homozygous mutants resulted in completely male sterile plants that were defective in pollen and anther development. Additionally, double homozygous-single heterozygous mutants were also male sterile although with varying levels of residual fertility. The fertility of these triple mutants was dependent upon the homeolog contributing the wild-type allele. Two heterologous Ms26/CYP704B genes, when transformed into a triple homozygous mutant background, completely restored male fertility, whereas a single gene was unable to restore fertility. Functional analysis of Ms26/CYP704B furthers the understanding of male fertility genes which can be utilized for the development of novel hybrid seed production systems in wheat.

  14. Cophylogeny of the anther smut fungi and their caryophyllaceous hosts: Prevalence of host shifts and importance of delimiting parasite species for inferring cospeciation

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    Yockteng Roxana

    2008-03-01

    Full Text Available Abstract Background Using phylogenetic approaches, the expectation that parallel cladogenesis should occur between parasites and hosts has been validated in some studies, but most others provided evidence for frequent host shifts. Here we examine the evolutionary history of the association between Microbotryum fungi that cause anther smut disease and their Caryophyllaceous hosts. We investigated the congruence between host and parasite phylogenies, inferred cospeciation events and host shifts, and assessed whether geography or plant ecology could have facilitated the putative host shifts identified. For cophylogeny analyses on microorganisms, parasite strains isolated from different host species are generally considered to represent independent evolutionary lineages, often without checking whether some strains actually belong to the same generalist species. Such an approach may mistake intraspecific nodes for speciation events and thus bias the results of cophylogeny analyses if generalist species are found on closely related hosts. A second aim of this study was therefore to evaluate the impact of species delimitation on the inferences of cospeciation. Results We inferred a multiple gene phylogeny of anther smut strains from 21 host plants from several geographic origins, complementing a previous study on the delimitation of fungal species and their host specificities. We also inferred a multi-gene phylogeny of their host plants, and the two phylogenies were compared. A significant level of cospeciation was found when each host species was considered to harbour a specific parasite strain, i.e. when generalist parasite species were not recognized as such. This approach overestimated the frequency of cocladogenesis because individual parasite species capable of infecting multiple host species (i.e. generalists were found on closely related hosts. When generalist parasite species were appropriately delimited and only a single representative of

  15. Identification of microRNAs and their target genes explores miRNA-mediated regulatory network of cytoplasmic male sterility occurrence during anther development in radish (Raphanus sativus L.

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    Wei Zhang

    2016-07-01

    Full Text Available MicroRNAs (miRNAs are a type of endogenous non-coding small RNAs that play critical roles in plant growth and developmental processes. Cytoplasmic male sterility (CMS is typically a maternally inherited trait and widely used in plant heterosis utilization. However, the miRNA-mediated regulatory network of CMS occurrence during anther development remains largely unknown in radish. In this study, a comparative small RNAome sequencing was conducted in floral buds of CMS line ‘WA’ and its maintainer line ‘WB’ by high-throughput sequencing. A total of 162 known miRNAs belonging to 25 conserved and 24 non-conserved miRNA families were isolated and 27 potential novel miRNA families were identified for the first time in floral buds of radish. Of these miRNAs, 28 known and 14 potential novel miRNAs were differentially expressed during anther development. Several target genes for CMS occurrence-related miRNAs encoding important transcription factors and functional proteins, which might be involved in multiple biological processes including auxin signaling pathways, signal transduction, miRNA target silencing, floral organ development and organellar gene expression. Moreover, the expression patterns of several CMS occurrence-related miRNAs and their targets during three stages of anther development were validated by qRT-PCR. In addition, a potential miRNA-mediated regulatory network of CMS occurrence during anther development was firstly proposed in radish. These findings contribute new insights into complex miRNA-mediated genetic regulatory network of CMS occurrence and advance our understanding of the roles of miRNAs during CMS occurrence and microspore formation in radish and other crops.

  16. Sex and parasites: genomic and transcriptomic analysis of Microbotryum lychnidis-dioicae, the biotrophic and plant-castrating anther smut fungus.

    Science.gov (United States)

    Perlin, Michael H; Amselem, Joelle; Fontanillas, Eric; Toh, Su San; Chen, Zehua; Goldberg, Jonathan; Duplessis, Sebastien; Henrissat, Bernard; Young, Sarah; Zeng, Qiandong; Aguileta, Gabriela; Petit, Elsa; Badouin, Helene; Andrews, Jared; Razeeq, Dominique; Gabaldón, Toni; Quesneville, Hadi; Giraud, Tatiana; Hood, Michael E; Schultz, David J; Cuomo, Christina A

    2015-06-16

    The genus Microbotryum includes plant pathogenic fungi afflicting a wide variety of hosts with anther smut disease. Microbotryum lychnidis-dioicae infects Silene latifolia and replaces host pollen with fungal spores, exhibiting biotrophy and necrosis associated with altering plant development. We determined the haploid genome sequence for M. lychnidis-dioicae and analyzed whole transcriptome data from plant infections and other stages of the fungal lifecycle, revealing the inventory and expression level of genes that facilitate pathogenic growth. Compared to related fungi, an expanded number of major facilitator superfamily transporters and secretory lipases were detected; lipase gene expression was found to be altered by exposure to lipid compounds, which signaled a switch to dikaryotic, pathogenic growth. In addition, while enzymes to digest cellulose, xylan, xyloglucan, and highly substituted forms of pectin were absent, along with depletion of peroxidases and superoxide dismutases that protect the fungus from oxidative stress, the repertoire of glycosyltransferases and of enzymes that could manipulate host development has expanded. A total of 14% of the genome was categorized as repetitive sequences. Transposable elements have accumulated in mating-type chromosomal regions and were also associated across the genome with gene clusters of small secreted proteins, which may mediate host interactions. The unique absence of enzyme classes for plant cell wall degradation and maintenance of enzymes that break down components of pollen tubes and flowers provides a striking example of biotrophic host adaptation.

  17. Rozwój warstw ściennych i otwieranie się pylnika u kilku dzikich gatunków ziemniaka (Solarium chacoense Bitt., S. phureja Juz. et Buk., 5. giberulosum Juz. et Buk., S. Commersonii Dun. [The development of the parietal layers and dehiscence of the anthers at some wild potato species (Solanum chacoense Bitt., S. phureja Juz. et Buk., S. giberulosum Juz. et Buk., and S. Commersonii Dun.

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    L. Hausbrandt

    2015-06-01

    Full Text Available The anthers in these species like in whole genus Solanum are poricidal still some differences have been observed in structure of their anther walls. The fibrous cells associated with dehiscence restricted usually to the area around the pore may form a single layer or may form compact mass often irregular in thickness or it may be lacking at all. Besides the apical pore one can observe a lateral dehiscence. By desintegra-tion of cells a gap is forming in the wall separating the two anther chambers which causes breaking it down. Then stomium like cells in epidermis contribute to the lateral opening.

  18. Improved production of doubled haploids of winter and spring triticale hybrids via combination of colchicine treatments on anthers and regenerated plants.

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    Ślusarkiewicz-Jarzina, Aurelia; Pudelska, Hanna; Woźna, Jolanta; Pniewski, Tomasz

    2017-08-01

    Double haploids (DH), obtained during androgenesis in vitro or by genome diploidisation in regenerated haploids, are one type of basic materials used in triticale breeding programmes. The aim of this study was to improve DH production by a combination of colchicine treatment methods on a sample of five winter and five spring triticale hybrids. Colchicine was applied in vitro either in the C17 medium to induce embryo-like structures (ELS) or in the 190-2 medium for green plant (GP) development. Regenerants which remained haploid were immersed in a colchicine solution either when placed on the medium prior to transferring to soil or when growing in pots, followed by the application or absence of cooling. Colchicine treatment during anther culture affected neither ELS nor GP development, but significantly increased the number of DH plants in comparison to spontaneous chromosome doubling. The highest efficiency was recorded when colchicine was applied in the induction medium (55%) versus the regeneration medium (44.5%) or no colchicine treatment (30%). The effectiveness of chromosome duplication in haploid plants ranged from 32 to 64.5% and it was the highest for the treatment on the medium followed by cooling. Individual hybrids differed regarding their capability of regeneration and chromosome doubling, which were consistent only to a low or moderate extent. However, taken together, winter and spring hybrids did not differ significantly. Combined colchicine application resulted in a high yield of DH production, 82.6% for all triticale hybrids, and can provide a considerable number of fertile DH lines for triticale breeding programmes.

  19. Pollination of Vietnamese Aspidistra xuansonensis (Asparagaceae) by female Cecidomyiidi flies: larvae of pollinator feed on fertile pollen in anthers of anthetic bisexual flowers.

    Science.gov (United States)

    Vislobokov, Nikolay A; Galinskaya, Tatiana V; Degtjareva, Galina V; Valiejo-Roman, Carmen M; Samigullin, Tahir H; Kuznetsov, Andrey N; Sokoloff, Dmitry D

    2014-09-01

    • Aspidistra is a species-rich, herbaceous monocot genus of tropical Southeast Asia. Most species are recently discovered and apparently endangered, though virtually nothing is known about their biology. Species of the genus are primarily distinguished using flower morphology, which is enormously diverse. However, the pollination process has not been directly observed in the center of diversity of the genus (N Vietnam and S China). Indirect and partly direct data on the only widely cultivated species of the genus (A. elatior) placed it among angiosperms with the most unusual pollination biology, though these data are highly controversial, suggesting pollen transfer by mollusks, crustaceans, flies, or possibly tiny soil invertebrates such as collembolans.• Pollination of Aspidistra xuansonensis in the center of diversity of the genus was studied using visual observations and videos and light and scanning electron microscopy investigation of flowers and their pollinators. Pollinators and their larvae were molecularly barcoded.• Aspidistra xuansonensis is pollinated by female cecidomyiid flies (gall midges). They oviposit on anthers, and larvae develop among the pollen mass. Molecular barcoding proved taxonomic identity of the larvae and the flies. The larvae neither damage floral parts nor cause gall formation, but feed on pollen grains by sucking out their content. The larvae move out of the flowers before decomposition starts. Carebara ants steal developing larvae from flowers but do not contribute to pollination.• More than one kind of myiophily is present in Aspidistra. Brood site pollination was documented for the first time in Aspidistra. The pollination system of A. xuansonensis differs from other kinds of brood site pollination in the exit of the larvae prior to the decomposition of floral parts. © 2014 Botanical Society of America, Inc.

  20. Loss of Arabidopsis GAUT12/IRX8 causes anther indehiscence and leads to reduced G lignin associated with altered matrix polysaccharide deposition

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    Hao, Zhangying; Avci, Utku; Tan, Li; Zhu, Xiang; Glushka, John; Pattathil, Sivakumar; Eberhard, Stefan; Sholes, Tipton; Rothstein, Grace E.; Lukowitz, Wolfgang; Orlando, Ron; Hahn, Michael G.; Mohnen, Debra

    2014-01-01

    GAlactUronosylTransferase12 (GAUT12)/IRregular Xylem8 (IRX8) is a putative glycosyltransferase involved in Arabidopsis secondary cell wall biosynthesis. Previous work showed that Arabidopsis irregular xylem8 (irx8) mutants have collapsed xylem due to a reduction in xylan and a lesser reduction in a subfraction of homogalacturonan (HG). We now show that male sterility in the irx8 mutant is due to indehiscent anthers caused by reduced deposition of xylan and lignin in the endothecium cell layer. The reduced lignin content was demonstrated by histochemical lignin staining and pyrolysis Molecular Beam Mass Spectrometry (pyMBMS) and is associated with reduced lignin biosynthesis in irx8 stems. Examination of sequential chemical extracts of stem walls using 2D 13C-1H Heteronuclear Single-Quantum Correlation (HSQC) NMR spectroscopy and antibody-based glycome profiling revealed a reduction in G lignin in the 1 M KOH extract and a concomitant loss of xylan, arabinogalactan and pectin epitopes in the ammonium oxalate, sodium carbonate, and 1 M KOH extracts from the irx8 walls compared with wild-type walls. Immunolabeling of stem sections using the monoclonal antibody CCRC-M138 reactive against an unsubstituted xylopentaose epitope revealed a bi-lamellate pattern in wild-type fiber cells and a collapsed bi-layer in irx8 cells, suggesting that at least in fiber cells, GAUT12 participates in the synthesis of a specific layer or type of xylan or helps to provide an architecture framework required for the native xylan deposition pattern. The results support the hypothesis that GAUT12 functions in the synthesis of a structure required for xylan and lignin deposition during secondary cell wall formation. PMID:25120548

  1. Anther and pollen development in some species of Poaceae (Poales Desenvolvimento da antera e do grão de pólen em espécies de Poaceae (Poales

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    AT. Nakamura

    2010-05-01

    Full Text Available Anther and pollen development were studied in Olyra humilis Nees, Sucrea monophylla Soderstr, (Bambusoideae, Axonopus aureus P. Beauv., Paspalum polyphyllum Nees ex Trin. (Panicoideae, Eragrostis solida Nees, and Chloris elata Desv. (Chloridoideae. The objective of this study was to characterise, embryologically, these species of subfamilies which are considered basal, intermediate and derivate, respectively. The species are similar to each other and to other Poaceae. They present the following characters: tetrasporangiate anthers; monocotyledonous-type anther wall development, endothecium showing annular thickenings, secretory tapetum; successive microsporogenesis; isobilateral tetrads; spheroidal, tricellular, monoporate pollen grains with annulus and operculum. Nevertheless, the exine patterns of the species studied are distinct. Olyra humilis and Sucrea monophylla (Bambusoideae show a granulose pattern, whereas in the other species, it is insular. In addition, Axonopus aureus and Paspalum polyphyllum (Panicoideae have a compactly insular spinule pattern, while Chloris elata and Eragrostis solida (Chloridoideae show a sparsely insular spinule pattern. The exine ornamentation may be considered an important feature at the infrafamiliar level.O desenvolvimento da antera e do grão de pólen de Olyra humilis Nees, Sucrea monophylla Soderstr. (Bambusoideae, Axonopus aureus P. Beauv., Paspalum polyphyllum Nees ex Trin. (Panicoideae, Eragrostis solida Nees and Chloris elata Desv. (Chloridoideae foi estudado visando caracterizar embriologicamente essas espécies de subfamílias consideradas basal, intermediária e derivada, respectivamente. As espécies são similares entre si e entre as demais Poaceae. Apresentam os seguintes caracteres: anteras tetrasporangiadas; desenvolvimento da parede da antera do tipo monocotiledôneo, endotécio com espessamento de parede anelar, tapete secretor; microsporogênese sucessiva; tétrades isobilaterais; grãos de

  2. Starch distribution in anthers, microspores and pollen grains in Aechmea recurvata (Klotzsch. L.B.Sm., Dyckia racinae L.B.Sm. and Tillandsia aeranthos (Loisel. L.B.Sm. (Bromeliaceae

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    João Marcelo Santos de Oliveira

    2015-03-01

    Full Text Available This paper presents a comparative description of the starch distribution in the anthers, microspores and pollen grains of Aechmea recurvata, Dyckia racinae and Tillandsia aeranthos. Flowers at different stages of development were processed according to plant microtechniques for observation by light microscope. Ten stages of embryological development were used as references for the comparative analysis of starch distribution and dynamics. The structural data showed a greater starch accumulation in the parietal layers and connective of D. racinae. It was observed that in the species studied, starch began to accumulate in microspore mother cell stage. The pollen grains in D. racinae and in T. aeranthos present two amylogenesis-amylolysis cycles, while A. recurvata presents only one. One amylogenesis-amylolysis cycle occurs in the parietal layers and/or connective tissue in all three species. The pollen grains in the three species are dispersed without starch and are characterized as the starchless type. Starch dynamics presents a close relation to the development of sporangia, microspores and pollen grains. It is believed that differences in the starch distribution and accumulation are related to the abiotic factors where the species are found.

  3. Efeitos de meios de cultura na formação de calos a partir de anteras de aspargo (Asparagus officinalis L. Effects of the culture media on the calli formation from Asparagus officinalis L. anthers

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    Vera Lúcia Bobrowski

    1995-07-01

    Full Text Available Técnicas auxiliares, como a cultura de anteras, possibilitam melhor eficiência na obtenção de novos genótipos de aspargo. Neste trabalho, foram utilizadas anteras contendo grãos de pólen, no estágio uninucleado, dos híbridos 56x22-8 e 47x22-8, em meio MS, semi-sólido e líquido, com diferentes concentrações de reguladores de crescimento: meio A - 0,5 mg/l BAP + 0,1 mg/l ANA + 0,5 mg/l 2,4-D + 20 g/l sacarose + 20 g/l glicose; meio B - 0,5 mg/l 2,4-D + 30 g/l sacarose; meio C - 3,0 mg/l ANA + 0,5 mg/l Kin + 30 g/l sacarose e meio D - 2,0 mg/l ANA + 0,5 mg/l Kin + 30 g/l sacarose. A formação de calos variou com o genótipo e o meio. Os meios líquidos apresentaram melhor eficiência na indução de calos do que os meios semi-sólidos. Para o híbrido 56x22-8 os melhores meios foram o A2 (líquido com 80,5% de indução de calos e dentre os meios semi-sólidos, o meio D1 com 41,6% de calos formados. Para o híbrido 47x22-8, o mais eficiente foi o meio D2 (líquido, com 68,1% de calos formados e, dentre os meios semi-sólidos, o D2, com 15,2%. Não ocorreram diferenças significativas, estatisticamente, entre os meios líquidos nem entre os meios semi-sólidos.Anther culture is an auxiliary technique to obtain new genotypes. In this work, anthers with pollen grains in the uninucleated stage of hybrids 56x22-8 and 47x22-8 were cultured in MS medium, semi-solid and liquid, with different concentrations of growth regulators: medium A - 0,5 mg/l BAP + 0,1 mg/l NAA + 0,5 mg/1 2,4-D + 20 g/l sucrose + 20 g/l glucose; medium B - 0,5 mg/1 2,4-D + 30 g/l sucrose; medium C - 3,0 mg/l NAA + 0,5 mg/l Kin + 30 g/l sucrose and medium D - 2,0 mg/l NAA + 0,5 mg/l Kin + 30 g/l sucrose. Callus formation varied with the genotype and the medium. Liquid media showed more efficiency in callus development than the semi-solids. For the hybrids 56x22-8 the best media were the liquid A2 with 80,5% of callus induction and among the semi-solids the D1, with 41

  4. Wound-induced expression of DEFECTIVE IN ANTHER DEHISCENCE1 and DAD1-like lipase genes is mediated by both CORONATINE INSENSITIVE1-dependent and independent pathways in Arabidopsis thaliana.

    Science.gov (United States)

    Ruduś, Izabela; Terai, Haruka; Shimizu, Takafumi; Kojima, Hisae; Hattori, Kazuki; Nishimori, Yuka; Tsukagoshi, Hironaka; Kamiya, Yuji; Seo, Mitsunori; Nakamura, Kenzo; Kępczyński, Jan; Ishiguro, Sumie

    2014-06-01

    Endogenous JA production is not necessary for wound-induced expression of JA-biosynthetic lipase genes such as DAD1 in Arabidopsis. However, the JA-Ile receptor COI1 is often required for their JA-independent induction. Wounding is a serious event in plants that may result from insect feeding and increase the risk of pathogen infection. Wounded plants produce high amounts of jasmonic acid (JA), which triggers the expression of insect and pathogen resistance genes. We focused on the transcriptional regulation of DEFECTIVE IN ANTHER DEHISCENCE1 and six of its homologs including DONGLE (DGL) in Arabidopsis, which encode lipases involved in JA biosynthesis. Plants constitutively expressing DAD1 accumulated a higher amount of JA than control plants after wounding, indicating that the expression of these lipase genes contributes to determining JA levels. We found that the expression of DAD1, DGL, and other DAD1-LIKE LIPASE (DALL) genes is induced upon wounding. Some DALLs were also expressed in unwounded leaves. Further experiments using JA-biosynthetic and JA-response mutants revealed that the wound induction of these genes is regulated by several distinct pathways. DAD1 and most of its homologs other than DALL4 were fully induced without relying on endogenous JA-Ile production and were only partly affected by JA deficiency, indicating that positive feedback by JA is not necessary for induction of these genes. However, DAD1 and DGL required CORONATINE INSENSITIVE1 (COI1) for their expression, suggesting that a molecule other than JA might act as a regulator of COI1. Wound induction of DALL1, DALL2, and DALL3 did not require COI1. This differential regulation of DAD1 and its homologs might explain their functions at different time points after wounding.

  5. BAP, 2,4-D e ácido acetilsalicílico na indução e diferenciação de calos em anteras de Coffea arabica L BAP, 2,4-D and acetyl-salicylic acid on the callus induction and differentiation in Coffea arabica L. anthers

    Directory of Open Access Journals (Sweden)

    Adelaide Siqueira Silva

    2009-10-01

    Full Text Available O melhoramento genético do cafeeiro por meio de métodos convencionais é um processo demorado para se obter uma nova cultivar. A redução desse tempo é possível através da produção de linhagens homozigóticas, oriundas de dihaplóides obtidas através da cultura de anteras. Objetivou-se aplicar a técnica da cultura de anteras em diferentes cvs. de Coffea arabica L. para induzir a formação de calos e regenerar plântulas di-haplóides, com uso de reguladores vegetais. Os experimentos foram conduzidos no laboratório de Biotecnologia Vegetal da Universidade Federal de Uberlândia (UFU. Anteras das cultivares Mundo Novo LCP-379-19 e Catuaí Vermelho H2077-2-5-44 foram inoculadas em meio MS suplementado com 2,0 mg L-1 de 2,4-D e AAS, nas concentrações de 0; 8; 16; 32 e 64 mg L-1. Calos de 'Catuaí Vermelho 44' foram subcultivados em meio MS acrescido de diferentes concentrações de BAP (0; 2; 4 e 8 mg L-1 e 2,4-D (0; 1; 2 e 4 mg L-1. Tanto para as cvs. Mundo Novo quanto para Catuaí Vermelho 44 o aumento das concentrações de AAS diminuiu a formação de próembrióides nos calos e somente o 2,4-D foi capaz de promover a formação de calos friáveis, porém o equilíbrio da auxina e da citocinina utilizadas no trabalho, favoreceram a produção de calos friáveis.Coffee plant breeding through conventional methods demands a long time to obtain new cultivars. The reduction of this period is possible through the production of homozygous lines, from dihaploids obtained via anther culture. The aim of this study was to apply the anther culture technique on different C. arabica L. cultivars to induce calli formation and to regenerate dihaploid seedlings with the use of plant growth regulators. The experiments were accomplished in the Plant Biotechnology laboratory at Uberlândia Federal University (UFU. Anthers of the cultivars Mundo Novo LCP-379-19 and Catuaí Vermelho H2077-2-5-44 were inoculated on MS medium supplemented with 2.0 mg L-1

  6. Establishment of plant regeneration system from anther culture of ...

    African Journals Online (AJOL)

    Frequencies of callus induction and shoot regeneration were 100 and 70.5%, respectively with the whole regeneration procedure completed in 40 days under light. This highly efficient, rapid regeneration system can be applied for both genetic transformation and doubled haploid plant induction. Key words: Tagetes patula, ...

  7. mbryogenic callus induction and regeneration in anther culture of ...

    African Journals Online (AJOL)

    preferred customer

    KN and IAA combinations, 2 mg/l KN combined with 1 mg/l IAA, was the most efficient for shoot regeneration. It was also found that 0.5 mg/l IBA ... lection cycle or used in development of synthetic cultivar of noug populations with desirable ..... SINET: Ethiop. J. Sci., 33(1), 2010. 53. Optimization of cold pre-treatment duration.

  8. Induction of microspore-derived embryos by anther culture in ...

    African Journals Online (AJOL)

    /L NAA, 1 mg/L BAP, 0.25% activated charcoal, 15 mg/L AgNO3, 30 g/L sucrose) and the Medium IV (modified MS medium containing 0.25% activated charcoal, 15 mg/L AgNO3, 4 mg/L NAA, 0.1mg/L BAP and with 0.5 mg/L ABA). There was ...

  9. Anther culture response in indica rice and variations in major ...

    African Journals Online (AJOL)

    Positive selection deems to be improvising those characters. The frequency distribution for number of panicles per plant and panicle length varied largely among the androclones in both direction of the parental mean. Whereas, all the androclones were found to be shorter than the parent and low yielder too. This study ...

  10. Pas de deux: An Intricate Dance of Anther Smut and Its Host

    Directory of Open Access Journals (Sweden)

    Su San Toh

    2018-02-01

    Full Text Available The successful interaction between pathogen/parasite and host requires a delicate balance between fitness of the former and survival of the latter. To optimize fitness a parasite/pathogen must effectively create an environment conducive to reproductive success, while simultaneously avoiding or minimizing detrimental host defense response. The association between Microbotryum lychnidis-dioicae and its host Silene latifolia serves as an excellent model to examine such interactions. This fungus is part of a species complex that infects species of the Caryophyllaceae, replacing pollen with the fungal spores. In the current study, transcriptome analyses of the fungus and its host were conducted during discrete stages of bud development so as to identify changes in fungal gene expression that lead to spore development and to identify changes associated with infection in the host plant. In contrast to early biotrophic phase stages of infection for the fungus, the latter stages involve tissue necrosis and in the case of infected female flowers, further changes in the developmental program in which the ovary aborts and a pseudoanther is produced. Transcriptome analysis via Illumina RNA sequencing revealed enrichment of fungal genes encoding small secreted proteins, with hallmarks of effectors and genes found to be relatively unique to the Microbotryum species complex. Host gene expression analyses also identified interesting sets of genes up-regulated, including those involving stress response, host defense response, and several agamous-like MADS-box genes (AGL61 and AGL80, predicted to interact and be involved in male gametophyte development.

  11. Cloning and expression analysis of a new anther-specific gene ...

    Indian Academy of Sciences (India)

    XUEFENG HAO

    Chen et al. 2011, 2012). Concurrently, an RNA-sequencing method was used to analyse differen- tial gene expression comparatively in blended flower buds of fertile and sterile plants in the 114AB genic male sterile– fertile line of C. annuum.

  12. Cloning and expression analysis of a new anther-specific gene ...

    Indian Academy of Sciences (India)

    XUEFENG HAO

    The process of germination and pollen development in. C. annuum could be influenced by the expression of these two genes, observed only in the flower buds of fertile plants in the mid stages (Chen et al. 2011, 2012). Concurrently, an RNA-sequencing method was used to analyse differen- tial gene expression ...

  13. Identification and Initial Characterization of the Effectors of an Anther Smut Fungus and Potential Host Target Proteins

    Directory of Open Access Journals (Sweden)

    Venkata S. Kuppireddy

    2017-11-01

    Full Text Available (1 Background: Plant pathogenic fungi often display high levels of host specificity and biotrophic fungi; in particular, they must manipulate their hosts to avoid detection and to complete their obligate pathogenic lifecycles. One important strategy of such fungi is the secretion of small proteins that serve as effectors in this process. Microbotryum violaceum is a species complex whose members infect members of the Caryophyllaceae; M. lychnidis-dioicae, a parasite on Silene latifolia, is one of the best studied interactions. We are interested in identifying and characterizing effectors of the fungus and possible corresponding host targets; (2 Methods: In silico analysis of the M. lychnidis-dioicae genome and transcriptomes allowed us to predict a pool of small secreted proteins (SSPs with the hallmarks of effectors, including a lack of conserved protein family (PFAM domains and also localized regions of disorder. Putative SSPs were tested for secretion using a yeast secretion trap method. We then used yeast two-hybrid analyses for candidate-secreted effectors to probe a cDNA library from a range of growth conditions of the fungus, including infected plants; (3 Results: Roughly 50 SSPs were identified by in silico analysis. Of these, 4 were studied further and shown to be secreted, as well as examined for potential host interactors. One of the putative effectors, MVLG_01732, was found to interact with Arabidopsis thaliana calcium-dependent lipid binding protein (AtCLB and with cellulose synthase interactive protein 1 orthologues; and (4 Conclusions: The identification of a pool of putative effectors provides a resource for functional characterization of fungal proteins that mediate the delicate interaction between pathogen and host. The candidate targets of effectors, e.g., AtCLB, involved in pollen germination suggest tantalizing insights that could drive future studies.

  14. Cultivate In Vitro Of Anthers Of Barley (Hordeum Vulgare L.) Vars. UNAGRO V-PM6 And DISSA

    International Nuclear Information System (INIS)

    Marquinez Casas, Xavier

    1994-01-01

    The barley is a autonomous cereal originated of the wild subspecies H. vulgare L. Only at the end of last century it acquired commercial importance with the establishment of the industry brewer (Chaparro and Moreno 1894); at the moment its national production is far from supplying the demand of the market. The Andean area is the most appropriate region for its cultivation in Colombia, mainly between 1800 and 3200 meters on the level of the sea, in the Boyaca, Cundinamarca and Narino departments. Their production is dedicated in a 80 at 85 for the industry brewer and malt industry and of the 15 at 20 for seeds, human food and animal

  15. Identification of miRNAs with potential roles in regulation of anther development and male-sterility in 7B-1 male-sterile tomato mutant

    Czech Academy of Sciences Publication Activity Database

    Omidvar, Vahid; Mohorianu, I.; Dalmay, T.; Fellner, Martin

    2015-01-01

    Roč. 16, OCT 28 (2015), s. 878 ISSN 1471-2164 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : 7B-1 mutation * Solanum lycopersicum * Male-sterility Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.867, year: 2015

  16. The impact of Cu treatment on phenolic and polyamine levels in plant material regenerated from embryos obtained in anther culture of carrot

    Czech Academy of Sciences Publication Activity Database

    Górecka, K.; Cvikrová, Milena; Kowalska, U.; Eder, Josef; Szafrańska, K.; Górecki, R.; Janas, K. M.

    2007-01-01

    Roč. 45, č. 1 (2007), s. 54-61 ISSN 0981-9428 R&D Projects: GA MŠk 1P05OC052 Institutional research plan: CEZ:AV0Z50380511 Source of funding: V - iné verejné zdroje Keywords : carrot culture * copper ions * embryo regeneration Subject RIV: GE - Plant Breeding Impact factor: 1.669, year: 2007

  17. Identification and Functional Analysis of microRNAs Involved in the Anther Development in Cotton Genic Male Sterile Line Yu98-8A

    Directory of Open Access Journals (Sweden)

    Xiaojie Yang

    2016-10-01

    Full Text Available Hybrid vigor contributes in a large way to the yield and quality of cotton (Gossypium hirsutum fiber. Although microRNAs play essential regulatory roles in flower induction and development, it is still unclear if microRNAs are involved in male sterility, as the regulatory molecular mechanisms of male sterility in cotton need to be better defined. In this study, two independent small RNA libraries were constructed and sequenced from the young buds collected from the sporogenous cell formation to the meiosis stage of the male sterile line Yu98-8A and the near-isogenic line. Sequencing revealed 1588 and 1536 known microRNAs and 347 and 351 novel miRNAs from male sterile and male fertile libraries, respectively. MicroRNA expression profiles revealed that 49 conserved and 51 novel miRNAs were differentially expressed. Bioinformatic and degradome analysis indicated the regulatory complexity of microRNAs during flower induction and development. Further RT-qPCR and physiological analysis indicated that, among the different Kyoto Encyclopedia Gene and Genomes pathways, indole-3-acetic acid and gibberellic acid signaling transduction pathways may play pivotal regulatory functions in male sterility.

  18. An anther- and petal-specific gene SlMF1 is a multicopy gene with homologous sequences on sex chromosomes

    Czech Academy of Sciences Publication Activity Database

    Matsunaga, S.; Lebel-Hardenack, S.; Kejnovský, Eduard; Vyskot, Boris; Grant, Sarah R.; Kawano, S.

    2005-01-01

    Roč. 80, - (2005), s. 395-401 ISSN 1341-7568 R&D Projects: GA ČR(CZ) GA204/05/2097 Institutional research plan: CEZ:AV0Z50040507 Keywords : dioecious plant * male flower * sex chromosomes Subject RIV: BO - Biophysics Impact factor: 1.081, year: 2005

  19. The interaction of 2,4-D application and mannitol pretreatment in anther and microspore culture of Hordeum vulgare L. cv. igri

    NARCIS (Netherlands)

    Hoekstra, S.; Bergen, S. van; Brouwershaven, I.R. van; Schilperoort, R.A.; Heidekamp, F.

    1996-01-01

    The influence of 2,4-dichlorophenoxyacetic acid (2,4-D) on embryo-like structures (ELS) and plant development from barley microspores was determined. Microspores cultured on filters enabled simple modification of growth regulator concentrations. Regeneration frequencies obtained with 2,4- D as

  20. Reference: 298 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available etophytes (pollen grains) takes place in a specialized structure called the anther. Successful pollen development, and thus reproduct...ion, requires high secretory activity in both anther tis

  1. Inquiring for a chance to obtain strawberry (Fragaria x ananassa Duch. dihaploids

    Directory of Open Access Journals (Sweden)

    Barbara Ciupka

    2014-01-01

    Full Text Available The possibility of dihaploid development from tetrahaploid anthers in strawberry has been tested in culture. From the total number of 4635 anthers taken from 57 tetrahaploid plants (secondary cycle of anther culture and 4042 anthers from 7 octoploid varieties - 119 plants were obtained. The success depended on the growing conditions of donor plants (field conditions appeared better and plant genotypes (tetrahaploids previously regenerated in vitro were better donors. The majority of plants regenerated from tetrahaploid anther callus (54.6% were mixoploids. The remaining plants were polyploids from 2n=4x=28 to 2n=8x=56. Only 3 mixoploid individuals had lower than 2n=4x=28 number of chromosomes. Plants regenerated from anther callus were capable of developing seeds and fruits. Seed germination was rather low and fruit yield varied. Still, it was possible to select a group of 12 plants, possibly of somaclonal origin, fit for further breeding.

  2. Isolation of low erucic acid-containing genotype of Indian mustard ...

    African Journals Online (AJOL)

    Reciprocal crosses were done between two cultivars; cv. RJ15 and cv. RLM198 of Indian mustard (Brassica juncea). Anther derived lines designated as A1 plants, were raised through anther culture from these F1 hybrid plants. 45% germination was obtained from distinctly shriveled and small A1 seeds and grown along ...

  3. Male function for ensuring pollination and reproductive success in ...

    Indian Academy of Sciences (India)

    In Berberis lycium anthers on alternate stamens dehisce, thus prolonging the male function so that pollination is affected and reproduction is ensured. The large pollen sac of each bithecous anther after the appearance of longitudinal dehiscence slit moves away from the filament while remaining attached at the tip of the ...

  4. Impact of genotype, age of tree and environmental temperature on ...

    African Journals Online (AJOL)

    Influence of ten different genotypes, age of trees and environmental temperature on induction of androgenesis and apperance albino horse chestnut embryos were studied. Efficiency of in vitro androgenesis via anther and microspore culture had been investigated. Microspores and anthers were used from the same closed ...

  5. Mutagenesis effects of X-irradiation on the germination, growth and ...

    African Journals Online (AJOL)

    Measurements at eight days interval were carried out on the plants' heights, its leaves widths, days to anther and silk for six consecutive times after planting. Results revealed, the day to anther (42) days and day to silk (35) days after planting respectively for the irradiated sects were delayed. A comparative study carried out ...

  6. Cloning and functional analysis in transgenic tobacco of a tapetum ...

    African Journals Online (AJOL)

    The 5'-flanking region of 1174 bp upstream of the translation start point (TSP) of a reported Arabidopsis anther-specific gene, Anther7 gene (ATA7), which putatively encodes a protein related to lipid transfer protein, was cloned and functionally analyzed in transgenic tobacco after been fused with β- glucuronidase (GUS) ...

  7. Regulatory networks in pollen development under cold stress

    Directory of Open Access Journals (Sweden)

    Kamal Dev Sharma

    2016-03-01

    Full Text Available Cold stress modifies anthers’ metabolic pathways to induce pollen sterility. Cold-tolerant plants, unlike the susceptible ones, produce high proportion of viable pollen. Anthers in susceptible plants, when exposed to cold stress, increase abscisic acid (ABA metabolism and reduce ABA catabolism. Increased ABA negatively regulates expression of tapetum cell wall bound invertase and monosaccharide transport genes resulting in distorted carbohydrate pool in anther. Cold-stress also reduces endogenous levels of the bioactive gibberellins (GAs, GA4 and GA7, in susceptible anthers by repression of the GA biosynthesis genes. Here we discuss recent findings on mechanisms of cold susceptibility in anthers which determine pollen sterility. We also discuss differences in regulatory pathways between cold-stressed anthers of susceptible and tolerant plants that decide pollen sterility or viability.

  8. Poor correlation between the removal or deposition of pollen grains and frequency of pollinator contact with sex organs.

    Science.gov (United States)

    Sakamoto, Ryota L; Morinaga, Shin-Ichi

    2013-09-01

    Pollinators deposit pollen grains on stigmas and remove pollen grains from anthers. The mechanics of these transfers can now be quantified with the use of high-speed video. We videoed hawkmoths, carpenter bees, and swallowtail butterflies pollinating Clerodendrum trichotomum. The number of grains deposited on stigmas did not vary significantly with the number of times pollinators contacted stigmas. In contrast, pollen removal from the anthers increased significantly with the number of contacts to anthers. Pollen removal varied among the three types of pollinators. Also, the three types carried pollen on different parts of their bodies. In hawkmoths and carpenter bees, a large number of contacted body part with anthers differed significantly from the body part that attached a large number of pollen grains. Our results indicate that a large number of contacts by pollinators does not increase either the male or female reproductive success of plants compared to a small number of contacts during a visit.

  9. Calcium controls the formation of vacuoles from mitochondria to regulate microspore development in wheat.

    Science.gov (United States)

    Li, Dong Xiao; Hu, Hai Yan; Li, Gan; Ru, Zhen Gang; Tian, Hui Qiao

    2017-09-01

    Potassium antimonite was used to investigate the localisation of calcium in developing wheat anthers to examine the relationship between Ca 2+ and pollen development. During anther development, calcium precipitate formation increased in anther wall cells prior to microspore mother cell meiosis and appeared in microspores, suggesting the presence of a calcium influx from anther wall cells into the locule. Initially, the precipitates in microspore cytoplasm primarily accumulated in the mitochondria and destroyed their inner membranes (cisterns) to become small vacuoles, which expanded and fused, ultimately becoming a large vacuole during microspore vacuolisation. After microspore division and large vacuole decomposition, many calcium precipitates again accumulated in the small vacuoles, indicating that calcium from the large vacuole moved back into the cytoplasm of bicellular pollen.

  10. The study of genotype, cold pretreatment, low-dose gamma irradiation and 2,4-D concentration effect on wheat doubled haploid production

    International Nuclear Information System (INIS)

    Naserian, B.; Vedadi, C.; Karbalaii, S.

    2005-01-01

    Full text: In this study, response of a cultivar (Atrak) and two lines (F3 2005 and F3 2104) of wheat , and effect of cold pretreatment, low dose gamma irradiation and 2,4-D (2,4 mg l -1 ) were investigated to anther culture response. Donar plants were grown under field conditions in early spring. Anthers were plated on modified CHB medium containing 2, 4-D (2, 4 mg l -1 ), 0.5 mg l -1 Kinetin and 90 g l -1 Sucrose. Percent of Callus formation in 100 anther and percent of plantlet in 100 calli were measured. Results indicated that genotype, cold pretreatment and 2,4-D concentrations had significant effect on anther culture response. F3 2005 showed highest callus induction and plantlet production and F3 2104 had lowest response. This experiment indicated that androgenic traits are controlled by genotype and environmental factors. Further more these traits are controlled independently. (author)

  11. Studies on the application of radiation for genetic transformation in higher plants

    International Nuclear Information System (INIS)

    Lee, Young Il; Song, Hi Sup; Kim, Jae Sung; Shin, In Chul; Lee, Sang Jae; Lee, Ki Woon; Lim, Yong Taek

    1992-02-01

    Present research carried out to develop the radiation application on the mutation research of genetic engineering. Some variants selected in M1 generation derived from the plantlet by the nodal stem culture of three potato cultivars irradiated with gamma rays, and the optimum dosage for mutation induction was revealed the range of 30 - 50 Gy of gamma ray. In the rice anther culture of the plant irradiated with gamma rays at different developmental stage of microspore, the haploidy callus formation rates were much higher in gamma ray irradiated anthers than those of non-irradiated, and the occurrence of a typical pollen was significantly increased up to 47% in the anthers irradiated with 30 Gy of gamma ray compared with 11% of non-irradiated anthers at the stage of pollen mother cell. A lot of variants were selected in rice, soybean, perilla and red pepper irradiated with gamma rays for breeding of earliness, short culm, high yielding and disease resistant mutant. (Author)

  12. Factors affecting quantity of pollen dispersal of spray cut chrysanthemum (Chrysanthemum morifolium).

    Science.gov (United States)

    Wang, Xiao-Guang; Wang, Hai-Bin; Chen, Fa-Di; Jiang, Jia-Fu; Fang, Wei-Min; Liao, Yuan; Teng, Nian-Jun

    2014-01-06

    Spray cut chrysanthemum is a vital flower with high ornamental value and popularity in the world. However, the excessive quantity of pollen dispersal of most spray cut chrysanthemum is an adverse factor during its flowering stage, and can significantly reduce its ornamental value and quickly shorten its vase life. More seriously, excessive pollen grains in the air are usually harmful to people, especially for those with pollen allergies. Therefore, in order to obtain some valuable information for developing spray cut chrysanthemum with less-dispersed or non-dispersed pollen in the future breeding programs, we here investigated the factors affecting quantity of pollen dispersal of spray cut chrysanthemum with four cultivars, i.e. 'Qx-097', 'Noa', 'Qx-115', and 'Kingfisher', that have different quantity of pollen dispersal. 'Qx-097' with high quantity of pollen dispersal has 819 pollen grains per anther, 196.4 disk florets per inflorescence and over 800,000 pollen grains per inflorescence. The corresponding data for 'Noa' with low quantity of pollen dispersal are 406, 175.4 and over 350,000, respectively; and 219, 144.2 and nearly 160,000 for 'Qx-115' without pollen dispersal, respectively. 'Kingfisher' without pollen dispersal has 202.8 disk florets per inflorescence, but its anther has no pollen grains. In addition, 'Qx-097' has a very high degree of anther cracking that nearly causes a complete dispersal of pollen grains from its anthers. 'Noa' has a moderate degree of anther cracking, and pollen grains in its anthers are not completely dispersed. However, the anthers of 'Qx-115' and 'Kingfisher' do not crack at all. Furthermore, microsporogenesis and pollen development are normal in 'Qx-097', whereas many microspores or pollen degenerate in 'Noa', most of them abort in 'Qx-115', and all of them degrade in 'Kingfisher'. These results suggest that quantity of pollen dispersal in spray cut chrysanthemum are mainly determined by pollen quantity per anther, and

  13. Programmed cell death promotes male sterility in the functional dioecious Opuntia stenopetala (Cactaceae).

    Science.gov (United States)

    Flores-Rentería, Lluvia; Orozco-Arroyo, Gregorio; Cruz-García, Felipe; García-Campusano, Florencia; Alfaro, Isabel; Vázquez-Santana, Sonia

    2013-09-01

    The sexual separation in dioecious species has interested biologists for decades; however, the cellular mechanism leading to unisexuality has been poorly understood. In this study, the cellular changes that lead to male sterility in the functionally dioecious cactus, Opuntia stenopetala, are described. The spatial and temporal patterns of programmed cell death (PCD) were determined in the anthers of male and female flowers using scanning electron microscopy analysis and histological observations, focusing attention on the transition from bisexual to unisexual development. In addition, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling assays were used as an indicator of DNA fragmentation to corroborate PCD. PCD was detected in anthers of both female and male flowers, but their patterns differed in time and space. Functionally male individuals developed viable pollen, and normal development involved PCD on each layer of the anther wall, which occurred progressively from the inner (tapetum) to the outer layer (epidermis). Conversely, functional female individuals aborted anthers by premature and displaced PCD. In anthers of female flowers, the first signs of PCD, such as a nucleus with irregular shape, fragmented and condensed chromatin, high vacuolization and condensed cytoplasm, occurred at the microspore mother cell stage. Later these features were observed simultaneously in all anther wall layers, connective tissue and filament. Neither pollen formation nor anther dehiscence was detected in female flowers of O. stenopetala due to total anther disruption. Temporal and spatial changes in the patterns of PCD are responsible for male sterility of female flowers in O. stenopetala. Male fertility requires the co-ordination of different events, which, when altered, can lead to male sterility and to functionally unisexual individuals. PCD could be a widespread mechanism in the determination of functionally dioecious species.

  14. Rice improvement involving altered flower structure more suitable to cross-pollination, using in vitro culture in combination with mutagenesis

    International Nuclear Information System (INIS)

    Min, S.K.

    1998-01-01

    Anther and somatic tissue culture in combination with mutagenesis were carried out to evaluate the efficiency of different mutagenic treatments of various in vitro culture materials, and to obtain some promising variants for rice improvement. Results indicated that in japonica rice radiation treatment of dry seeds and young panicles influenced the percentage of green plantlets regeneration from anther culture. Both treatments increased significantly the percentage of regenerated green plant lets in comparison with the control

  15. Optimization of controlled pollination in avocado (persea americana Mill., Lauraceae)

    OpenAIRE

    Alcaraz Arco, María Librada; Hormaza Urroz, José Ignacio

    2014-01-01

    Avocado has a singular synchronous protogynous dichogamy breeding system that promotes outcrossing. In this work different steps have been optimized to improve controlled pollinations in avocado in order to perform basic studies of reproductive biology and directed crosses in breeding programs. The results show that, in order to achieve successful fruit set, male flowers should be collected when all the anthers have dehisced and the pollen transferred by direct contact of the anthers with the...

  16. The influence of several factors on the efficiency of androgenesis in carrot.

    Science.gov (United States)

    Górecka, Krystyna; Krzyzanowska, Dorota; Górecki, Ryszard

    2005-01-01

    The influence of cultivar, donor plant and culture procedure on the efficiency of androgenesis was studied in carrot anther culture. Experiments were carried out on five carrot cultivars: CxC 9900 F1, Lucky B F1, HCM, Beta III and Perfekcja, which were chosen because of their high carotene contents. Two procedures of anther culture were compared: (1) incubation in darkness for two weeks, followed by exposure to continuous light and transfer onto a fresh medium of the same composition; and (2) incubation in darkness until embryos appeared, without transfer onto a fresh medium. Temperature was +27 degrees C all the time. Genotype played an important role in the process of androgenesis in carrot anther culture. The efficiency was the highest in cv. HCM - 5.6 embryos per 100 anthers. Considerable differences in the capacity for androgenesis were observed between individual donor plants. The ratio of embryos obtained per 100 anthers for cv. HCM varied from 0.0 to 48.9. The second procedure of anther culture proved to be more efficient, cheaper and less complicated.

  17. Cloning and characterisation of a putative pollen-specific polygalacturonase gene (CpPG1) differentially regulated during pollen development in zucchini (Cucurbita pepo L.).

    Science.gov (United States)

    Carvajal, F; Garrido, D; Jamilena, M; Rosales, R

    2014-03-01

    Studies in zucchini (Cucurbita pepo L. spp. pepo) pollen have been limited to the viability and morphology of the mature pollen grain. The enzyme polygalacturonase (PG) is involved in pollen development and pollination in many species. In this work, we study anther and pollen development of C. pepo and present the cloning and characterisation of a putative PG CpPG1 (Accession no. HQ232488) from pollen cDNA in C. pepo. The predicted protein for CpPG1 has 416 amino acids, with a high homology to other pollen PGs, such as P22 from Oenothera organensis (76%) and PGA3 from Arabidopsis thaliana (73%). CpPG1 belongs to clade C, which comprises PGs expressed in pollen, and presents a 34 amino acid signal peptide for secretion towards the cell wall. DNA-blot analysis revealed that there are at least another two genes that code for PGs in C. pepo. The spatial and temporal accumulation of CpPG1 was studied by semi-quantitative- and qRT-PCR. In addition, mRNA was detected only in anthers, pollen and the rudimentary anthers of bisexual flowers (only present in some zucchini cultivars under certain environmental conditions that trigger anther development in the third whorl of female flowers). However, no expression was detected in cotyledons, stem or fruit. Furthermore, CpPG1 mRNA was accumulated throughout anther development, with the highest expression found in mature pollen. Similarly, exo-PG activity increased from immature anther stages to mature anthers and mature pollen. Overall, these data support the pollen specificity of this gene and suggest an involvement of CpPG1 in pollen development in C. pepo. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  18. The examination of Hevea brasiliensis plants produced by in vitro culture and mutagenesis by DNA fingerprinting techniques

    International Nuclear Information System (INIS)

    Low, F.C.; Atan, S.; Jaafar, H.

    1998-01-01

    Rubber (Hevea brasiliensis) plants derived from anther and ovule culture as well as gamma-irradiated plants were examined by several DNA marker techniques. These include restriction fragment length polymorphisms (RFLPs), random amplified polymorphic DNA (RAPD), sequence tagged microsatellite sites (STMS), DNA amplification fingerprinting (DAF) and amplified fragment length polymorphisms (AFLPs). Compared to control plants produced by vegetative propagation (cutting and budding), plants produced by in vitro culture appeared to have a reduction in the number of rDNA loci. Two RAPD protocols were compared and found to be similar in amplification of the major DNA bands. After confirmation that the RAPD method adopted was reproducible, the technique was applied to the present studies. Eight out of the 60 primers screened were able to elicit polymorphisms between pooled DNA from in vitro culture plants. Variations in DNA patterns were observed between pooled DNA samples of anther-derived plants as well as between anther-derived and ovule-derived plants. Comparisons of RAPD patterns obtained between anther-derived plants exposed to increasing dosages of gamma-irradiation with non irradiated anther-derived plants revealed distinct DNA polymorphisms. The changes in DNA profiles did not appear to be correlated to the dosage of irradiation. Since somaclonal variation was detected, it was difficult to identify changes which were specifically caused by irradiation. Application of the STMS technique to tag micro satellite sequences (GA) n , (TA) n and (TTA) n in the hydroxymethylglutaryl coenzyme A reductase-1 (hmgr-1) gene failed to detect differences between plants derived from anther and ovule culture. Although restriction endonuclease digestions with methylation sensitive enzymes suggested that four in vitro culture plants examined exhibited similar digestion patterns as the controls, a change in cytosine methylation in one anther-derived plant was detected. Examination of

  19. Cells of the connective tissue differentiate and migrate into pollen sacs

    Science.gov (United States)

    Iqbal, M. C. M.; Wijesekara, Kolitha B.

    2002-01-01

    In angiosperms, archesporial cells in the anther primordium undergo meiosis to form haploid pollen, the sole occupants of anther sacs. Anther sacs are held together by a matrix of parenchyma cells, the connective tissue. Cells of the connective tissue are not known to differentiate. We report the differentiation of parenchyma cells in the connective tissue of two Gordonia species into pollen-like structures (described as pseudopollen), which migrate into the anther sacs before dehiscence. Pollen and pseudopollen were distinguishable by morphology and staining. Pollen were tricolpate to spherical while pseudopollen were less rigid and transparent with a ribbed surface. Both types were different in size, shape, staining and surface architecture. The ratio of the number of pseudopollen to pollen was 1:3. During ontogeny in the connective tissue, neither cell division nor tetrad formation was observed and hence pseudopollen were presumed to be diploid. Only normal pollen germinated on a germination medium. Fixed preparations in time seemed to indicate that pseudopollen migrate from the connective tissue into the anther sac.

  20. Genetic and cytological diversity in cherry tree accessions (Eugenia involucrata DC in Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    Divanilde Guerra

    2016-09-01

    Full Text Available This study aimed to evaluate the genetic and cytological diversity and stability of 35 cherry tree accessions collected in Rio Grande do Sul. We used 15 RAPD (Random Amplified Polymorphic DNA molecular markers and performed cytological analysis and number count of anthers. Analyses of genetic diversity allowed the separation of accessions into four groups, resulting in an average of 8.93 bands per primer amplified, 7.89 polymorphic bands, 88.08% of polymorphism and 86% of genetic similarity. Cytological analyses of gametic cells allowed for the characterization of accessions as diploids with n=11. In these, the average of meiotic cells considered normal was 82.12%; average pollen viability was 92.44% and in vitro germination was 40.26%; the average number of anthers was 161.85 anthers/flowers. Therefore, the accessions evaluated showed high genetic similarity and cytological stability and can be used in commercial plantations or hybridizations.

  1. Fluid dynamics of hydrophilous pollination in Ruppia (widgeon grass)

    Science.gov (United States)

    Musunuri, Naga; Bunker, Daniel; Pell, Susan; Fischer, Ian; Singh, Pushpendra

    2014-11-01

    The aim of this work is to understand the physics underlying the mechanisms of two-dimensional aquatic pollen dispersal, known as hydrophily, that have evolved in several genera of aquatic plants, including Halodule, Halophila, Lepilaena, and Ruppia. We selected Ruppia, which grows in the wetlands of the New Jersey/New York metropolitan area, for this study. Our experiments show that the pollen grains from an anther suddenly disperse and form a monolayer when they come in contact with a water surface. This is a crucial first step in the formation of floating porous pollen structures called ``pollen rafts,'' which often contain pollen grains from several anthers. The formation of porous pollen rafts increases the probability of pollination by increasing the two-dimensional reach of the pollen from each individual anther. The work was supported by National Science Foundation.

  2. Complete sterility studies in three mutants of cowpea (Vigna Unguiculata (L.) walp

    International Nuclear Information System (INIS)

    Adu-Dapaah, H. K.; Singh, B. B.; Fatokun, C. A.

    1999-01-01

    Three completely-sterile cowpea mutants IT85D-3625, IT85D-3628, IT85D-3641 obtained from spontaneous mutation and gamma irradiation were-characterized. Reciprocal crosses between them and fertile plants failed to set pods. These lines showed significant differences with respect to various traits such as number of pollen grain per anther, anther length and width, plant height, anther indehiscence,unopened flower buds, and premature abortion of pods and seeds. The major cause of sterility was chromosome aberrations. Complete sterility in each of the three lines was conditioned by a simple recessive gene pair. Sterility in each of the three mutants was associated with floral aberrations. The symbols cs 1 , cs 2 and cs 3 are being assigned to IT85D-3625, IT85D-2628 and IT85D-3641 respectively. The three mutants were homogeneous with reference to sterility inheritance. (au)

  3. Transcriptional regulation of male-sterility in 7B-1 male-sterile tomato mutant.

    Directory of Open Access Journals (Sweden)

    Vahid Omidvar

    Full Text Available The 7B-1 tomato (Solanum lycopersicum L. cv Rutgers is a male-sterile mutant with enhanced tolerance to abiotic stress, which makes it a potential candidate for hybrid seed breeding and stress engineering. To underline the molecular mechanism regulating the male-sterility in 7B-1, transcriptomic profiles of the 7B-1 male-sterile and wild type (WT anthers were studied using mRNA sequencing (RNA-Seq. In total, 768 differentially expressed genes (DEGs were identified, including 132 up-regulated and 636 down-regulated transcripts. Gene ontology (GO enrichment analysis of DEGs suggested a general impact of the 7B-1 mutation on metabolic processes, such as proteolysis and carbohydrate catabolic process. Sixteen candidates with key roles in regulation of anther development were subjected to further analysis using qRT-PCR and in situ hybridization. Cytological studies showed several defects associated with anther development in the 7B-1 mutant, including unsynchronized anther maturation, dysfunctional meiosis, arrested microspores, defect in callose degradation and abnormal tapetum development. TUNEL assay showed a defect in programmed cell death (PCD of tapetal cells in 7B-1 anthers. The present study provides insights into the transcriptome of the 7B-1 mutant. We identified several genes with altered expression level in 7B-1 (including beta-1,3 glucanase, GA2oxs, cystatin, cysteine protease, pectinesterase, TA29, and actin that could potentially regulate anther developmental processes, such as meiosis, tapetum development, and cell-wall formation/degradation.

  4. Phenotype-gene: 800 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available 800 http://metadb.riken.jp/db/SciNetS_ria224i/cria224u3ria224u976i abnormal for tr...ait of structure in organ named anther for AT2G43790 Bush Susan M et al. 2007. J. Exp. Bot. 58(8):2181-91. http://metadb.riken...named anther http://metadb.riken.jp/db/SciNetS_ria224i/cria224u1ria224u582i AT2G43790

  5. It takes two to tango: self incompatibility in the bromeliad Tillandsia streptophylla (Bromeliaceae) in Mexico.

    Science.gov (United States)

    Ramírez Morillo, Ivón M; Chi May, Francisco; Carnevali, Germán; May Pat, Filogonio

    2009-09-01

    Floral phenology and breeding system of Tillandsia streptophylla (Bromeliaceae) were studied in a low inundated forest in Yucatan, Mexico. During the flowering season, from March to August, terminal scapose 1-branched, paniculate inflorescences are produced with one flower per branch opening per day, over a period of 11-29 days. Flowers are tubular, light violet, with the stigma placed below the anthers, both protruding above the corolla. Flowers are protandrous, with anthers releasing pollen from 0500 hours and stigma becoming receptive around 0900 hours. Controlled experimental crosses suggest that Tillandsia streptophylla is self incompatible and therefore, pollinator-dependent.

  6. Untitled

    Indian Academy of Sciences (India)

    Figs, 12-27. Fig. 12, Cross-section of anther, X200. Figs. 13-15. A part of anther icte, x1,620. Figs. 16-18. Pollen grains, x2,125. Fig. 19. Archesporial cell, X2,125. Fig. 20. Megaspore mother cell, X2,125. Figs. 21-22. Tetrads, X2,125. Fig. 23. Functional nega- spore, X2,125. Fig. 24. Four-nucleate embryo-sac, X2,125. Fig. 25.

  7. Amomum nilgiricum (Zingiberaceae, a new species from Western Ghats, India

    Directory of Open Access Journals (Sweden)

    Thomas VP

    2012-01-01

    Full Text Available A new species of Amomum Roxb. from Western Ghats of Kerala is illustrated and described. Amomum nilgiricum VP.Thomas & M.Sabu, sp. nov. shows similarity with A. masticatorium Thwaites inlong drying ligule with an acuminate apex, pubescent anther and echinate capsules, but differs in clump forming habit with non-stoloniferous rhizomes, tomentose lamina beneath, long corolla tube, obovate to rhomboid labellum with clefted apex and without any colour design, emarginate anther crest and reduced staminodes. Detailed description, illustration, photographs, conservation status, and distributional details are provided.

  8. Pollen parameters estimates of genetic variability among newly ...

    African Journals Online (AJOL)

    Estimates of some pollen parameters where used to assess the genetic diversity among some newly selected Nigerian Roselle (Hibiscus sabdariffa L.). Standard procedures were used to determine the pollen parameters such as: percentage pollen fertility, percentage pollen sterility, pollen diameters as well as anther ...

  9. Evaluation of pollen production in Bromus catharticus Vahl and Guadua trinii (Nees Nees ex Rupr. (Poaceae for interpretation of fossil data

    Directory of Open Access Journals (Sweden)

    Jefferson Nunes Radaeski

    2016-12-01

    Full Text Available We evaluated pollen production per anther, per flower, and per spikelet of the grassland species Bromus catharticus and the forest taxon Guadua trinii (Poaceae, which have divergent pollination syndrome. We collected ten anthers of each taxon to determine differences in pollen production based on pollination system. Anthers were macerated and pollen grains were counted in a Neubauer chamber. Pollen morphology was observed using optical and scanning electron microscopy to establish relationships between pollen grain production and morphology. The anemophilous species Bromus catharticus (2,556,000 pollen grains/spikelet has twice the pollen production per anther and per spikelet compared to Guadua trinii (1,716,000 pollen grains/spikelet, a species that requires biotic assistance for pollination. Pollen grain size is inversely proportional to production. Microechinate ornamentation, which is not expected to occur in anemophilous species, was observed on pollen of both taxa. Our results indicate that the frequency of forest Poaceae in the quaternary records may be underestimated while frequency of grassland taxa may be overestimated, leading to misrepresentation of the respective flora in this period.

  10. Res May 2017 Cover Tp 04.05.17

    Indian Academy of Sciences (India)

    System5

    ... free ends of petals. Stamens 4, attached to the mouth of corollatube; anthers arrowhead-shaped, style exserted, stigmaintwo lobes, hairy. Fruitaberry,. 5-6 mm across, black when ripe. Flowers and fruits appear between November and June. This plantis distributed across the plains and Ghats - India, Sri Lanka and Burma.

  11. Cloning and functional analysis in transgenic tobacco of a tapetum ...

    African Journals Online (AJOL)

    Jane

    2010-10-11

    Oct 11, 2010 ... State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University,. Beijing ..... of GUS activity in the anther and pollen of transgenic tobacco T0 plants conferred by the constructs. ..... A chalcone synthase-like gene is highly expressed in the tapetum of.

  12. Transactivation of Ds by Ac-transposase gene fusions in tobacco

    NARCIS (Netherlands)

    Rommens, Caius M.T.; Haaren, Mark J.J. van; Buchel, Annemarie S.; Mol, Joseph N.M.; Tunen, Arjen J. van; Nijkamp, H. John J.; Hille, Jacques

    1992-01-01

    To study regulation of the (Ds) transposition process in heterologous plant species, the transposase gene of Ac was fused to several promoters that are active late during plant development. These promoters are the flower-specific chalcone synthase A promoter (CHS A), the anther-specific chalcone

  13. The Arabidopsis male-sterile mutant dde2-2 is defective in the ALLENE OXIDE SYNTHASE gene encoding one of the key enzymes of the jasmonic acid biosynthesis pathway

    DEFF Research Database (Denmark)

    von Malek, Bernadette; van der Graaff, Eric; Schneitz, Kay

    2002-01-01

    The Arabidopsis thaliana (L.) Heynh. mutant delayed-dehiscence2-2 (dde2-2) was identified in an En1/Spm1 transposon-induced mutant population screened for plants showing defects in fertility. The dde2-2 mutant allele is defective in the anther dehiscence process and filament elongation and thus e...

  14. Cotton Flowers: Pollen and Petal Humidity Sensitivities Determine Reproductive Competitiveness in Diverse Environments

    Science.gov (United States)

    Genetic diversity in reproductive abiotic stress tolerance has been reported for cotton [Gossypium hirsutum (L.)] based upon the percentage of anther dehiscence of mature pollen in adverse environments. This study investigated the abiotic stress tolerance of mature pollen and identified genetic vari...

  15. In vitro mutagenesis in Rosa hybrida using oryzalin as a mutagen ...

    African Journals Online (AJOL)

    Jane

    2011-06-27

    Jun 27, 2011 ... and genetic similarity among anther-derived monoploid regenera determined by RAPD analysis. Plant Cell Tissue Organ Cult. 53: 49-. 58. Vijaya N, Satyanarayan G, Prakash J, Pierk RLM (1991). Effect of culture media and growth regulators on in vitro Propagation of rose. Plant Sci. Biotechnol. Agric.

  16. R eprodu ced by Sabin et G atew ay u n der licen ce gran ted by th e ...

    African Journals Online (AJOL)

    with strategic planning, setting goals and objectives;' and'·decisibn making, 'with regard to. management ... To respond proactively to the digital transformation of oral health care, dental professionals must become .... one place to an~ther. fou'r categ~rf~s; Laptops,. Notebooks, Subn,otebooks, PersonaL Digital Assistants.

  17. Pollen grain morphology of three species and a variety of Ocimum ...

    African Journals Online (AJOL)

    Pollen grains from fresh anthers of three species and a variety of Ocimum occurring in South-western Nigeria were collected and acetolysed. This was in an attempt to use the pollen charac-teristics to delimit, classify and trace probable evolutionary relationships among the taxa. The structural morphology of the pollen ...

  18. Carbohydrate changes during flower senescence of the Easter Lily (Lilium Longiflorum Thunb.)

    Science.gov (United States)

    This research was initiated to examine changes in ethanol soluble carbohydrates and cell wall neutral sugar composition in various floral organs of cut Lilium longiflorum Thunb. (Easter lily) flowers. Fresh weight of anthers decreased sharply, reaching a minimum level 3 days post-anthesis (DPA). T...

  19. Induced androgenesis in vitro in mutated populations of barley, Hordeum vulgare

    Czech Academy of Sciences Publication Activity Database

    Vagera, Jiří; Novotný, J.; Ohnoutková, Ludmila

    2004-01-01

    Roč. 77, č. 1 (2004), s. 55-61 ISSN 0167-6857 R&D Projects: GA MZe QF4133; GA ČR GA521/03/0113; GA MZe QE1093 Institutional research plan: CEZ:AV0Z5038910 Keywords : anther culture * chlorophyll mutations * enhanced embryogenesis Subject RIV: GE - Plant Breeding Impact factor: 1.028, year: 2004

  20. Reduction of ploidy level by androgenesis in intergeneric Lolium-Festuca hybrids for turf grass breeding

    Czech Academy of Sciences Publication Activity Database

    Kopecký, David; Lukaszewski, A.J.; Gibeault, V.

    2005-01-01

    Roč. 45, č. 1 (2005), s. 274-281 ISSN 0011-183X Institutional research plan: CEZ:AV0Z50380511 Keywords : anther culture * pentaploid hybrids * perenne L. Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.925, year: 2005

  1. The effects of calcium on the expression of genes involved in ...

    African Journals Online (AJOL)

    USER

    2010-06-14

    Jun 14, 2010 ... involved in ethylene biosynthesis and signal perception during tomato flower abscission. Tao Xu ... plants; for example, calcium affects “triple responses” of etiolated tomato seedlings (Zhang et al., .... anther cone, exhibited a yellow color and the floral opening angle was approximately 90°. The flowers were ...

  2. In vitro regeneration of lychee (Litchi chinensis Sonn.)

    African Journals Online (AJOL)

    Administrator

    Visual observations of the cultures were made every week and the percentage of cultures showing callusing, shoot bud differentiation / development and/or ..... In their work on lychee anther culture, Fu and Tang (1983) used 2,4-D and NAA for callus induction and a different cytokinin,. (kinetin) but the same auxin (IAA) for ...

  3. Differential transcript abundance and genotypic variation of four putative allergen-encoding gene families in melting peach

    NARCIS (Netherlands)

    Yang, Zhaowei; Ma, Yingtao; Chen, Lin; Xie, Rangjin; Zhang, Xianqi; Zhang, Bo; Lu, Meidan; Wu, Shandong; Gilissen, Luud J. W. J.; van Ree, Ronald; Gao, Zhongshan

    2011-01-01

    We analysed the temporal and spatial transcript expression of the panel of 18 putative isoallergens from four gene families (Pru p 1-4) in the peach fruit, anther and leaf of two melting cultivars, to gain insight into their expression profiles and to identify the key family members. Genotypic

  4. Differential transcript abundance and genotypic variation of four putative allergen-encoding gene families in melting peach

    NARCIS (Netherlands)

    Yang, Z.; Ma, Y.; Chen, L.; Xie, R.; Zhang, X.; Zhang, B.; Lu, M.; Wu, S.; Gilissen, L.J.W.J.; Ree, van R.; Gao, Z.

    2011-01-01

    We analysed the temporal and spatial transcript expression of the panel of 18 putative isoallergens from four gene families (Pru p 1–4) in the peach fruit, anther and leaf of two melting cultivars, to gain insight into their expression profiles and to identify the key family members. Genotypic

  5. Ethylene production and post-pollination development in Dendrobium flowers treated with foreign pollen

    NARCIS (Netherlands)

    Ketsa, S.; Bunya-Atichart, K.; Doorn, van W.G.

    2001-01-01

    Dendrobium ‘Pompadour’ flowers fade early following pollination. This is associated with increased ethylene production and early epinasty. These effects are also produced by application of 1-aminocyclopropane-1-carboxylic acid (ACC) on the stigma. Pollen (one anther each) from Ruellia tuberosa L.

  6. USE OF CELL ENGINEERING FOR DEVELOPMENT OF THE CONSTANT INITIAL BREEDING MATERIAL OF WHITE HEAD CABBAGE CV. NADZEJA AND CMS SAMPLES

    Directory of Open Access Journals (Sweden)

    A. V. Yakimovich

    2013-01-01

    Full Text Available The anther derived androgenic plants of white head cabbage cv. Nadzeja and CMS samples were obtained. The cytological analysis of ploidy level of regenerated plants and doubled haploids obtained by treatment of meristems with colchicine was performed. On the basis of androgenic doubled hap loids of white head cabbage genotypes the seed plants were developed.

  7. Toward in vitro fertilization in Brachiaria spp.

    NARCIS (Netherlands)

    Dusi, D.; Alves, E.R.; Willemse, M.T.M.; Falcao, R.; Valle, do C.B.; Carneiro, V.T.C.

    2010-01-01

    Brachiaria are forage grasses widely cultivated in tropical areas. In vitro pollination was applied to accessions of Brachiaria spp. by placing pollen of non-dehiscent anthers on a solid medium near isolated ovaries. Viability and in vitro germination were tested in order to establish good

  8. The expression of VFL and VvTFL1 genes in relation to the effects of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-05-10

    May 10, 2010 ... in the ovule primordia and calyptra (Figures 4P and Q). Before flowering, VFL expression was detected in the calyx, calyptra, stigma, anther, entire ovary wall and ovule. (Figure 4R) and the expression in the nucellus tissue was more obvious (Figure 4S). The effect of GAs on the expression patterns of.

  9. Fulltext PDF

    Indian Academy of Sciences (India)

    System5

    2017-07-05

    Jul 5, 2017 ... light brown. Leaves are opposite, elliptic-ovate, thick and leathery. Flowers are white, in dense axillary clusters, 5mmin diameter. Calyx is cup-shaped and lightgreen. Petals free. Stamens are many; anthers with lightbluetinge. Stigma simple, longerthan the flower. Fruitaberry, blackwhenripe. Flowers ...

  10. Recombinant pollen allergens from Dactylis glomerata: preliminary evidence that human IgE cross-reactivity between Dac g II and Lol p I/II is increased following grass pollen immunotherapy

    NARCIS (Netherlands)

    Roberts, A. M.; van Ree, R.; Cardy, S. M.; Bevan, L. J.; Walker, M. R.

    1992-01-01

    We previously described the isolation of three identical complementary DNA (cDNA) clones, constructed from Orchard/Cocksfoot grass (Dactylis glomerata) anther messenger RNA (mRNA), expressing a 140,000 MW beta-galactosidase fusion protein recognized by IgE antibodies in atopic sera. Partial

  11. Inheritance patterns of the response to in vitro doubled haploid induction in perennial ryegrass (Lolium perenne L.)

    Czech Academy of Sciences Publication Activity Database

    Begheyn, R. F.; Roulund, N.; Vangsgaard, K.; Kopecký, David; Studer, B.

    2017-01-01

    Roč. 130, č. 3 (2017), s. 667-679 ISSN 0167-6857 Institutional support: RVO:61389030 Keywords : Androgenesis * Androgenic capacity * Anther culture * Doubled haploid (DH) * Perennial ryegrass (Lolium perenne L.) Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 2.002, year: 2016

  12. Res Oct 2016 Cover Tp 07.10.16

    Indian Academy of Sciences (India)

    System5

    Leaves are feather-compound. Flowers are borne in branched axillary inflorescence, small and bisexual. Sepals are covered with dense brownish scales. Stamens are 10 that form a hallow tube at the base arround the pistil. Anthers are free. Fruits are pear-shaped (1.7–2.8 cm long, 1.2-2.3 cm in diam.) and dehescent.

  13. Stamen morphoanatomy of Dyckia Schult.f. (Bromeliaceae, Pitcairnioideae species: new data for taxonomic use

    Directory of Open Access Journals (Sweden)

    Jordano Dorval Tavares de Carvalho

    2016-01-01

    Full Text Available ABSTRACT This study presents a morphoanatomical analysis of Dyckia ibicuiensis , D. polyclada and D. racinae stamens. Flowers at anthesis were desiccated and their stamens were processed using common light microscopic techniques. Morphologically, the androecium in these species is differentiated by the disposition of the stamens around the gynoecium and by general anther characteristics. Included stamens, with antesepalous filaments different from those of the antepetalous, anthers in a radial disposition, always curved, and sporangia facing the gynoecium characterize D. ibicuiensis and D. racinae . This configuration results from the filament connation, as well as special anatomical characteristics of the anthers, such as the connective with thickenings. In addition, these species are differentiated by the U-shaped thickening in the endothecium. D. polyclada is characterized by its small, free and exserted stamens, with a very short common tube, its anthers, that are not curved or organized around the gynoecium, and its divergent sporangia. The anatomical and morphological characteristics identified here are important for characterization of these species. Considering that the androecium is important in the delimitation of Dyckia , the increased use of these data should be equally important for other species and infrageneric groupings.

  14. Fulltext PDF

    Indian Academy of Sciences (India)

    Trincomali Wood of Tiliaceae is a tall evergreen tree with straight trunk, smooth brownish-grey bark and simple broad leaves. Inflorescence is much branched with white flowers. Stamens are many with golden yellow anthers. Fruit is a capsule with six spreading wings. Seeds bear short stiff hairs that cause skin irritation.

  15. Influence of genotype and plant growth regulator on somatic ...

    African Journals Online (AJOL)

    USER

    2010-06-28

    Jun 28, 2010 ... Zemdirbyste Agric. 94(4): 129-138. Burbulis N, Kupriene R, zilenaite L (2004). Embryogenesis, callogenesis and plant regeneration from anther cultures of spring rape (Brassica napus L.). Acta Universitatis Latviensis, Biol. 676: 153-158. Chen JT, Chang C, Chang WC (1999). Direct somatic embryogenesis.

  16. TRL1 gene expression in tomato (Solanum lycopersicum) floral organs after γ-irradiation

    International Nuclear Information System (INIS)

    Bondarenco, V.S.; Barbacar, N.I.

    2009-01-01

    The article describes the expression patterns of a novel RAD16-like TRL1 (tomato RAD16-like 1) gene in the floral organs of tomato during anther meiosis and mature flower stages. The data on the induction of the TRL1 expression as a result of γ-irradiation is discussed. (authors)

  17. Effect of activated charcoal, abscisic acid and polyethylene glycol on ...

    African Journals Online (AJOL)

    USER

    2010-06-21

    Jun 21, 2010 ... The influence of activated charcoal (AC), abscisic acid (ABA) and polyethylene glycol (PEG) on the maturation and conversion of horse chestnut (Aesculus hippocastanum L.) androgenic embryos were tested. Androgenic embryos originating from microspores and anther culture were maturated over 90.

  18. Effect of seasonal collection on callus Induction, proliferation and ...

    African Journals Online (AJOL)

    Hevea brasiliensis that is grown in Thailand and Southeast Asia is a very valuable source of natural rubber. However, few studies have been conducted to evaluate the effects of seasonal effect on plantlet regenera-tion through somatic embryogenesis from anther culture. Thus, this study discussed the effect of season on ...

  19. The oligolectic bee Osmia brevis sonicates Penstemon flowers for pollen: A newly documented behavior for the Megachilidae

    Science.gov (United States)

    James H. Cane

    2014-01-01

    Flowers with poricidally dehiscent anthers are typically nectarless but are avidly visited and often solely pollinated by bees that sonicate the flowers to harvest pollen. Sonication results from shivering the thoracic flight muscles. Honey bees (Apis) and the 4,000+ species of Megachilidae are enigmatic in their seeming inability to sonicate flowers. The oligolectic...

  20. Res July 2017 Cover Page Tp 05.07.17

    Indian Academy of Sciences (India)

    System5

    2017-07-05

    Jul 5, 2017 ... light brown. Leaves are opposite, elliptic-ovate, thick and leathery. Flowers are white, in dense axillary clusters, 5mmin diameter. Calyx is cup-shaped and lightgreen. Petals free. Stamens are many; anthers with lightbluetinge. Stigma simple, longerthan the flower. Fruitaberry, blackwhenripe. Flowers ...

  1. Fulltext PDF

    Indian Academy of Sciences (India)

    2016-01-22

    Jan 22, 2016 ... staminal movement. This makes the dehisced anthers stick to the stigma and deposit pollen there. [Sharma S and Verma S 2016 Male function for ensuring pollination and reproductive success in Berberis ... cemes, insects affect pollination by triggering the movement .... ecology (Pergamon Press: Oxford).

  2. A New Species of Kaempferia (Zingiberaceae from Southern Laos

    Directory of Open Access Journals (Sweden)

    Chayan Picheansoonthon

    2008-12-01

    Full Text Available A new species of Kaempferia L. (Zingiberaceae from Southern Laos, K. champasakensis, is described and illustrated. This new taxon can be easily recognized by its pure white flowers with the labellum divided two-third to the base and the large white ovate-elliptic to suborbicular anther crest with greatly varied apex. Relationship with other taxa is also discussed.

  3. Segregation distortion in F2 and doubled haploid populations of ...

    Indian Academy of Sciences (India)

    Keywords. anther culture; linkage map; skewed segregation; Oryza sativa L. Journal of ... (1998) revealed that two of the five regions showing segregation distortion in an indica–japonica DH population contributed to increase DH plant generation. ..... Lu C., Shen L., Tan Z., Xu Y., He P., Chen Y. and Zhu L. 1996 Com-.

  4. Breeding of newly licensed wheat variety Huapei 8 and improved ...

    African Journals Online (AJOL)

    ajl yemi

    2011-12-28

    Dec 28, 2011 ... progeny selection method. H2 was the best selection generation for traits with high heredity ability, and. H3 was the best selection for grain traits and yield test. Consequently, we bred and licensed six new wheat varieties derived from anther culture and significantly reduced breeding time to three to five.

  5. Palynological studies in tribe Chlorideae (Poaceae) from salt range ...

    African Journals Online (AJOL)

    Jane

    2011-08-15

    Aug 15, 2011 ... To determine pollen fertility, acetocarmine and glycerin jelly was used by the modified techniques used by Khan and Stace (1999). Anthers were squashed .... World. Kew bulletin additional series 13, Royal Botanic gardens,. Kew. p. 389. Edeoga HO, Okoli BE (1996). Apomictic behaviour in Costus after C.

  6. Plant species descriptions show signs of disease.

    Science.gov (United States)

    Hood, Michael E; Antonovics, Janis

    2003-11-07

    It is well known that diseases can greatly influence the morphology of plants, but often the incidence of disease is either too rare or the symptoms too obvious for the 'abnormalities' to cause confusion in systematics. However, we have recently come across several misinterpretations of disease-induced traits that may have been perpetuated into modern species inventories. Anther-smut disease (caused by the fungus Microbotryum violaceum) is common in many members of the Caryophyllaceae and related plant families. This disease causes anthers of infected plants to be filled with dark-violet fungal spores rather than pollen. Otherwise, their vegetative morphology is within the normal range of healthy plants. Here, we present the results of a herbarium survey showing that a number of type specimens (on which the species name and original description are based) in the genus Silene from Asia are diseased with anther smut. The primary visible disease symptom, namely the dark-violet anthers, is incorporated into the original species descriptions and some of these descriptions have persisted unchanged into modern floras. This raises the question of whether diseased type specimens have erroneously been given unique species names.

  7. Anthesis, the infectious process and disease progress curves for fusarium head blight in wheat

    Directory of Open Access Journals (Sweden)

    Erlei Melo Reis

    2016-06-01

    Full Text Available ABSTRACT Fusarium head blight of wheat (Triticum aestivum, caused by the fungus Gibberella zeae, is a floral infecting disease that causes quantitative and qualitative losses to winter cereals. In Brazil, the sanitary situation of wheat has led to research in order to develop strategies for sustainable production, even under adverse weather conditions. To increase the knowledge of the relationship among the presence of anthesis, the infectious process, the disease progress and the saprophytic fungi present in wheat anthers, studies were conducted in the experimental field of University of Passo Fundo (UPF, using the cultivar Marfim, in the 2011 growing season. The disease incidence in spikes and spikelets was evaluated. The presence of exserted anthers increased the spike exposure time to the inoculum. The final incidence of fusarium head blight, in the field, was dependent on the presence of exserted anthers. The disease followed an aggregation pattern and its evolution increased with time, apparently showing growth according to secondary cycles. The fungi isolated from exserted anthers (Alternaria sp., Fusarium sp., Drechslera spp. and Epicoccum sp. did not compete for the infection site of fusarium head blight in wheat, not interfering with the incidence of F. graminearum.

  8. Effects of embryo induction media and pretreatments in isolated ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-11-16

    Nov 16, 2009 ... gene transfer (Kasha et al., 1995; Zheng, 2003; Abdollahi et al., 2007). Nowadays ... somatic tissue in anther culture (Bonet and Olmedilla,. 2000). ..... J. Biol. Sci. 10: 3141-3145. Bonet FJ, Olmedilla A (2000). Structural changes during early embryogenesis in wheat pollen. Protoplasma 211: 94-102. Chen Y ...

  9. Pollination and seed production in Xerophyllum tenax (Melanthiaceae) in the Cascade Range of central Oregon.

    Science.gov (United States)

    Nan C. Vance; Peter Bernhardt; Retha M. Edens

    2004-01-01

    Xerophyllum tenax is a mass-flowering, nectarless herb in which self-pollination is unavoidable as anthers shed pollen onto the three, receptive stigmatic ridges attached to each pistil within a few hours after expansion of the perianth. We compared the pollination system with reproductive success in this species through controlled, hand-...

  10. Short-term high temperature growth conditions during vegetative-to-reproductive phase transition irreversibly compromise cell wall invertase-mediated sucrose catalysis and microspore meiosis in grain sorghum

    Science.gov (United States)

    Grain sorghum (Sorghum bicolor L. Moench) crop yield is significantly compromised by high temperature stress-induced male sterility, and is attributed to reduced cell wall invertase (CWI)-mediated sucrose hydrolysis in microspores and anthers leading to altered carbohydrate metabolism and starch def...

  11. Studies on the Flora of the Guianas. 1. Croton macradenis (sect. Podostachys, fam. Euphorbiacece), a new species from the Guianas

    NARCIS (Netherlands)

    Görts-van Rijn, A.R.A.; Punt, W.

    1983-01-01

    A new species of Croton, sect. Podostachys (C. macradenis) from French Guiana and Suriname is described. It has remarkable long glands. The distinctive characters of the species are the following: long, tubiform glands at the base of the leaves; male flowers with a hairy receptacle and 5-6 anthers ;

  12. nature of ergastic substances in some nigerian asteraceae 160

    African Journals Online (AJOL)

    DR. AMINU

    morphological characters e.g. capitula, highly reduced and modified florets, replacement of calyx by pappus, five epipetalous syngenecious anthers; bicarpellary condition; syncarpous inferior and unilocular ovary with single basal anatropus ovule, fruits as a rule are achenes (seeds). Seeds are the primary storage organs ...

  13. Defective Pollen Wall 2 ( DPW2 ) Encodes an Acyl Transferase Required for Rice Pollen Development

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Dawei [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Shi, Jianxin [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Rautengarten, Carsten [Univ. of Melbourne (Australia). ARC Centre of Excellence in Plant Cell Walls; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint BioEnergy Inst. and Biological Systems and Engineering Division; Yang, Li [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Qian, Xiaoling [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Uzair, Muhammad [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Zhu, Lu [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Luo, Qian [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; An, Gynheung [Kyung Hee Univ., Yongin (Korea). Crop Biotech Inst.; Waßmann, Fritz [Univ. of Bonn (Germany). Inst. of Cellular and Molecular Botany; Schreiber, Lukas [Univ. of Bonn (Germany). Inst. of Cellular and Molecular Botany; Heazlewood, Joshua L. [Univ. of Melbourne (Australia). ARC Centre of Excellence in Plant Cell Walls; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint BioEnergy Inst. and Biological Systems and Engineering Division; Scheller, Henrik Vibe [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint BioEnergy Inst. and Biological Systems and Engineering Division; Univ. of California, Berkeley, CA (United States). Dept. of Plant and Microbial Biology; Hu, Jianping [Michigan State Univ., East Lansing, MI (United States). Dept. of Energy Plant Research Lab.; Zhang, Dabing [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences; Univ. of Adelaide, SA (Australia). School of Agriculture, Food and Wine; Liang, Wanqi [Shanghai Jiao Tong Univ. (China). Joint International Research Lab. of Metabolic and Developmental Sciences

    2016-05-31

    Aliphatic and aromatic lipids are both essential structural components of the plant cuticle, an important interface between the plant and environment. Although cross links between aromatic and aliphatic or other moieties are known to be associated with the formation of leaf cutin and root and seed suberin, the contribution of aromatic lipids to the biosynthesis of anther cuticles and pollen walls remains elusive. In this study, we characterized the rice (Oryza sativa) male sterile mutant, defective pollen wall 2 (dpw2), which showed an abnormal anther cuticle, a defective pollen wall, and complete male sterility. Compared with the wild type, dpw2 anthers have increased amounts of cutin and waxes and decreased levels of lipidic and phenolic compounds. DPW2 encodes a cytoplasmically localized BAHD acyltransferase. In vitro assays demonstrated that recombinant DPW2 specifically transfers hydroxycinnamic acid moieties, using v-hydroxy fatty acids as acyl acceptors and hydroxycinnamoyl-CoAs as acyl donors. Thus, The cytoplasmic hydroxycinnamoyl-CoA:v-hydroxy fatty acid transferase DPW2 plays a fundamental role in male reproduction via the biosynthesis of key components of the anther cuticle and pollen wall.

  14. Res Feb 2017 Cover Tp 04.02.17

    Indian Academy of Sciences (India)

    System5

    Leaves are opposite, elliptic-oblong and leathery. Flowers are in a terminal cluster with many branches and are stalked; corolla with a short basal tube and a wheel-like free end, 6-8 mm in diameter. Stamens 5 and the anthers are yellowish. Fruit broadly ellipsoidal, red initially turning black when mature, 8-. 15 x 6–10 mm.

  15. Agricultural Extension Officers' Knowledge About the Role of ...

    African Journals Online (AJOL)

    Also 90.91% (40) and 68.18% (30) of the Extension Officers considered bees and lepidopterans respectively as pollinators. Furthermore, 88.64% (39) of the respondents indicated that pollinators transfer pollen grains from the anther to the stigma. Majority of the respondents (mean of1.95) considered increased fruit ...

  16. Successful development of a shed-microspore culture protocol for doubled haploid production in Indonesian hot pepper (Capsicum annuum L.)

    NARCIS (Netherlands)

    Supena, E.D.J.; Suharsono, S.; Jacobsen, E.; Custers, J.B.M.

    2006-01-01

    Various systems of anther and microspore cultures were studied to establish an efficient doubled haploid production method for Indonesian hot pepper (Capsicum annuum L.). A shed-microspore culture protocol was developed which outperformed all the previously reported methods of haploid production in

  17. The Effect of a Model's HIV Status on Self-Perceptions: A Self-Protective Similarity Bias.

    Science.gov (United States)

    Gump, Brooks B.; Kulik, James A.

    1995-01-01

    Examined how information about another person's HIV status influences self-perceptions and behavioral intentions. Individuals perceived their own personalities and behaviors as more dissimilar to anther's if that person's HIV status was believed positive compared with negative or unknown. Exposure to HIV-positive model produced greater intentions…

  18. Breeding of newly licensed wheat variety Huapei 8 and improved ...

    African Journals Online (AJOL)

    H2 was the best selection generation for traits with high heredity ability, and H3 was the best selection for grain traits and yield test. Consequently, we bred and licensed six new wheat varieties derived from anther culture and significantly reduced breeding time to three to five years. Huapei 8 was the newest released wheat ...

  19. 1772-IJBCS-Article-Abolade Adekunle

    African Journals Online (AJOL)

    hp

    A hybrid swarm involving O. sativa, O. glaberrima and O. longistaminata occuring in Jebba, Nigeria was studied to investigate the processes involved in the population dynamics. Reproductive parameters such as pollen stainability, pollen size, anther structure, seed set were investigated. The chromosomes of the hybrid.

  20. Brief communication

    Indian Academy of Sciences (India)

    2016-01-22

    Jan 22, 2016 ... nism of anther dehiscence and pollination. Flower dependency on insect visit to affect pollination was determined by pollina- tion experiments including unassisted selfing, manual cross- pollination and manual self-pollination, and percent fruit set was determined when flowering was over using the formula:.

  1. What to Follow "Make" and What to Follow "Do"--Corpus-Based Study on the De-Lexical Use of "Make" and "Do" in Native Speakers' and Chinese Students' Writing

    Science.gov (United States)

    Fu, Zhuqin

    2006-01-01

    To many Chinese students, learning the words such as "make" and "do" seems a piece of cake, yet learning how to use them appropriately is anther case. This paper aims to investigate Chinese learners' use of the verbs "make" and "do", two major representatives of high-frequency words from the perspective of…

  2. Flowering Trees

    Indian Academy of Sciences (India)

    Trincomali Wood of Tiliaceae is a tall evergreen tree with straight trunk, smooth brownish-grey bark and simple broad leaves. Inflorescence is much branched with white flowers. Stamens are many with golden yellow anthers. Fruit is a capsule with six spreading wings. Seeds bear short stiff hairs that cause skin irritation.

  3. Successfully combating prejudice

    Indian Academy of Sciences (India)

    Lawrence

    postdoctoral research I joined S. C. Maheshwari in the same department. This was a very rewarding period. I worked on vari- ous aspects of biochemistry of differentiation in plants, effects of plant hormones on transcription, and stumbled upon production of haploids through anther cultures of Datura innoxia. I felt very.

  4. The manifold characters of orbicules: structural diversity, systematic significance, and vectors for allergens

    NARCIS (Netherlands)

    Vinckier, S.; Cadot, P.; Smets, E.

    2005-01-01

    In the anthers of flowering plants, gymnosperms, and seed ferns, tiny (¡1 mm) granules might occur on the radial and innermost tangential wall of secretory tapetum cells. These sporopollenin granules develop simultaneously with the pollen exine and are called orbicules or Ubisch bodies. The present

  5. Cloning and molecular characterization of a copper chaperone gene ...

    African Journals Online (AJOL)

    Administrator

    2011-06-20

    Jun 20, 2011 ... scion interaction and mature budded clones exhibit significant intraclonal variability (Clément-Demange et al.,. 2007). A new type of “selfrooting juvenile clone (JC)” was generated from somatic plant production through embryo- genesis issued from rubber-tree anther explants (Wang et al., 1980; Chen et al.

  6. Allium : CGN downloadable dataset

    NARCIS (Netherlands)

    Hintum, van T.J.L.

    2014-01-01

    By 2014-26-06 data on experiments was available for the following traits. / Anther color 50 observations on 50 accessions / Bolting tendency 93 observations on 93 accessions / Botrytis aclada 34 observations on 19 accessions / Botrytis squamosa 15 observations on 9 accessions / Bulb base shape 354

  7. is regulated during fruit ripening and senescense, and involved

    Indian Academy of Sciences (India)

    The other tissues (such as shoots, young leaves, petals and anthers) were derived from the same pear trees of the local orchard. These samples were frozen immediately in liquid nitrogen and then stored at −80. ◦. C for RNA isolation. Fruit treatment. The mesocarp discs of pear fruit collected at 10 d after har- vest were ...

  8. Distribution of orbicules in Annonaceae mirrors evolutionary trend in angiosperms

    NARCIS (Netherlands)

    Huysmans, S.; Verstraete, B.; Smets, E.; Chatrou, L.W.

    2010-01-01

    Background and aims - Orbicules or Ubisch bodies have been recorded in many angiosperm families and although the first observations date back to 1865, their function in the anther remains enigmatic. In flowering plants a general evolutionary trend is observed from common occurrence of orbicules in

  9. A New Secondary Pollen Presentation Mechanism from a Wild Ginger (Zingiber densissimum) and Its Functional Roles in Pollination Process.

    Science.gov (United States)

    Fan, Yong-Li; Kress, W John; Li, Qing-Jun

    2015-01-01

    Secondary pollen presentation (SPP), a floral mechanism of reproductive adaptation, has been described for more than 200 years, with nine types SPP recorded. However, few studies have been done experimentally to link the floral mechanism of SPP to its functional roles in pollination process. This study aims to describe a new SPP mechanism from a wild ginger (Zingiber densissimum, Zingiberaceae) and explore how the pollen arrangement of SPP affects pollen removal during the interaction with different pollinators. Field observations and experiments revealed that flowers lasted for less than one day. The breeding system was partially self-incompatible. Two bee species, Macropis hedini (which carried pollen dorsally) and Amegilla zonata (which carried pollen ventrally) were the primary pollinators. About a third of pollen grains were relocated from the anther to the labellum staminode of flowers through the adherence of aggregated pollen chains, while other grains were presented on the anther. In a single visit, each bee species removed pollen grains from both the labellum staminode and the anther. Macropis hedini was more effective than Amegilla zonata. Our study describes a new SPP mechanism in angiosperms. The new SPP mode enables pollen grains presented on the anther and the labellum staminode simultaneously via the adherence of aggregated pollen chains, thus promoting pollen to be taken away by different pollinators. This SPP mechanism plays a key role during pollen removal and may have evolved under the pressure to improve male fitness.

  10. A New Secondary Pollen Presentation Mechanism from a Wild Ginger (Zingiber densissimum and Its Functional Roles in Pollination Process.

    Directory of Open Access Journals (Sweden)

    Yong-Li Fan

    Full Text Available Secondary pollen presentation (SPP, a floral mechanism of reproductive adaptation, has been described for more than 200 years, with nine types SPP recorded. However, few studies have been done experimentally to link the floral mechanism of SPP to its functional roles in pollination process. This study aims to describe a new SPP mechanism from a wild ginger (Zingiber densissimum, Zingiberaceae and explore how the pollen arrangement of SPP affects pollen removal during the interaction with different pollinators.Field observations and experiments revealed that flowers lasted for less than one day. The breeding system was partially self-incompatible. Two bee species, Macropis hedini (which carried pollen dorsally and Amegilla zonata (which carried pollen ventrally were the primary pollinators. About a third of pollen grains were relocated from the anther to the labellum staminode of flowers through the adherence of aggregated pollen chains, while other grains were presented on the anther. In a single visit, each bee species removed pollen grains from both the labellum staminode and the anther. Macropis hedini was more effective than Amegilla zonata.Our study describes a new SPP mechanism in angiosperms. The new SPP mode enables pollen grains presented on the anther and the labellum staminode simultaneously via the adherence of aggregated pollen chains, thus promoting pollen to be taken away by different pollinators. This SPP mechanism plays a key role during pollen removal and may have evolved under the pressure to improve male fitness.

  11. It is a matter of timing: asynchrony during pollen development and its consequences on pollen performance in angiosperms-a review.

    Science.gov (United States)

    Carrizo García, Carolina; Nepi, Massimo; Pacini, Ettore

    2017-01-01

    Functional pollen is needed to successfully complete fertilization. Pollen is formed inside the anthers following a specific sequence of developmental stages, from microsporocyte meiosis to pollen release, that concerns microsporocytes/microspores and anther wall tissues. The processes involved may not be synchronous within a flower, an anther, and even a microsporangium. Asynchrony has been barely analyzed, and its biological consequences have not been yet assessed. In this review, different processes of pollen development and lifetime, stressing on the possible consequences of their differential timing on pollen performance, are summarized. Development is usually synchronized until microsporocyte meiosis I (occasionally until meiosis II). Afterwards, a period of mostly asynchronous events extends up to anther opening as regards: (1) meiosis II (sometimes); (2) microspore vacuolization and later reduction of vacuoles; (3) amylogenesis, amylolysis, and carbohydrate inter-conversion; (4) the first haploid mitosis; and (5) intine formation. Asynchrony would promote metabolic differences among developing microspores and therefore physiologically heterogeneous pollen grains within a single microsporangium. Asynchrony would increase the effect of competition for resources during development and pollen tube growth and also for water during (re)hydration on the stigma. The differences generated by developmental asynchronies may have an adaptive role since more efficient pollen grains would be selected with regard to homeostasis, desiccation tolerance, resilience, speed of (re)hydration, and germination. The performance of each pollen grain which landed onto the stigma will be the result of a series of selective steps determined by its development, physiological state at maturity, and successive environmental constrains.

  12. Genomic comparisons of two Bacillus subtilis biocontrol strains with different modes of actions

    Science.gov (United States)

    Bacillus subtilis strains AS 43.3 and OH131.1 were isolated from wheat anthers and shown to be efficacious in managing Fusarium head blight in greenhouse and some field trials. Chemical analysis of the cell-free culture supernatant identified B. subtilis strain AS 43.3 to be a potent producer of the...

  13. microRNAs involved in auxin signalling modulate male sterility under high-temperature stress in cotton (Gossypium hirsutum).

    Science.gov (United States)

    Ding, Yuanhao; Ma, Yizan; Liu, Nian; Xu, Jiao; Hu, Qin; Li, Yaoyao; Wu, Yuanlong; Xie, Sai; Zhu, Longfu; Min, Ling; Zhang, Xianlong

    2017-09-01

    Male sterility caused by long-term high-temperature (HT) stress occurs widely in crops. MicroRNAs (miRNAs), a class of endogenous non-coding small RNAs, play an important role in the plant response to various abiotic stresses. To dissect the working principle of miRNAs in male sterility under HT stress in cotton, a total of 112 known miRNAs, 270 novel miRNAs and 347 target genes were identified from anthers of HT-insensitive (84021) and HT-sensitive (H05) cotton cultivars under normal-temperature and HT conditions through small RNA and degradome sequencing. Quantitative reverse transcriptase-polymerase chain reaction and 5'-RNA ligase-mediated rapid amplification of cDNA ends experiments were used to validate the sequencing data. The results show that miR156 was suppressed by HT stress in both 84021 and H05; miR160 was suppressed in 84021 but induced in H05. Correspondingly, SPLs (target genes of miR156) were induced both in 84021 and H05; ARF10 and ARF17 (target genes of miR160) were induced in 84021 but suppressed in H05. Overexpressing miR160 increased cotton sensitivity to HT stress seen as anther indehiscence, associated with the suppression of ARF10 and ARF17 expression, thereby activating the auxin response that leads to anther indehiscence. Supporting this role for auxin, exogenous Indole-3-acetic acid (IAA) leads to a stronger male sterility phenotype both in 84021 and H05 under HT stress. Cotton plants overexpressing miR157 suppressed the auxin signal, and also showed enhanced sensitivity to HT stress, with microspore abortion and anther indehiscence. Thus, we propose that the auxin signal, mediated by miRNAs, is essential for cotton anther fertility under HT stress. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  14. Characterization of a caleosin expressed during olive (Olea europaea L. pollen ontogeny

    Directory of Open Access Journals (Sweden)

    Rodríguez-García María

    2011-08-01

    Full Text Available Abstract Background The olive tree is an oil-storing species, with pollen being the second most active site in storage lipid biosynthesis. Caleosins are proteins involved in storage lipid mobilization during seed germination. Despite the existence of different lipidic structures in the anther, there are no data regarding the presence of caleosins in this organ to date. The purpose of the present work was to characterize a caleosin expressed in the olive anther over different key stages of pollen ontogeny, as a first approach to unravel its biological function in reproduction. Results A 30 kDa caleosin was identified in the anther tissues by Western blot analysis. Using fluorescence and transmission electron microscopic immunolocalization methods, the protein was first localized in the tapetal cells at the free microspore stage. Caleosins were released to the anther locule and further deposited onto the sculptures of the pollen exine. As anthers developed, tapetal cells showed the presence of structures constituted by caleosin-containing lipid droplets closely packed and enclosed by ER-derived cisternae and vesicles. After tapetal cells lost their integrity, the caleosin-containing remnants of the tapetum filled the cavities of the mature pollen exine, forming the pollen coat. In developing microspores, this caleosin was initially detected on the exine sculptures. During pollen maturation, caleosin levels progressively increased in the vegetative cell, concurrently with the number of oil bodies. The olive pollen caleosin was able to bind calcium in vitro. Moreover, PEGylation experiments supported the structural conformation model suggested for caleosins from seed oil bodies. Conclusions In the olive anther, a caleosin is expressed in both the tapetal and germ line cells, with its synthesis independently regulated. The pollen oil body-associated caleosin is synthesized by the vegetative cell, whereas the protein located on the pollen exine and

  15. The effect of ozone on pollen development in Lolium perenne L

    Energy Technology Data Exchange (ETDEWEB)

    Schoene, K.; Franz, J.-Th.; Masuch, G

    2004-10-01

    Perennial ryegrass plants (Lolium perenne L.) were exposed in 'Closed-Top Chambers' to different ozone concentrations and to charcoal filtered ambient air to study the effect of ozone on the development of pollen. Ozone at ambient (65 nl l{sup -1}, 8 h) and elevated (110 nl l{sup -1}, 4 h) concentrations affected the maturing of pollen by inhibiting starch accumulation in pollen throughout the anther. Affected pollen persisted in the vacuolated state while normal pollen in the same anther were filled with amyloplasts. The percentage of underdeveloped pollen--determined in transversal sections--was significantly higher in exposed plants than in plants grown in filtered air. Results indicate that ozone stress was responsible for the disrupted development of pollen in L. perenne.

  16. Auxins reverse plant male sterility caused by high temperatures.

    Science.gov (United States)

    Sakata, Tadashi; Oshino, Takeshi; Miura, Shinya; Tomabechi, Mari; Tsunaga, Yuta; Higashitani, Nahoko; Miyazawa, Yutaka; Takahashi, Hideyuki; Watanabe, Masao; Higashitani, Atsushi

    2010-05-11

    With global warming, plant high temperature injury is becoming an increasingly serious problem. In wheat, barley, and various other commercially important crops, the early phase of anther development is especially susceptible to high temperatures. Activation of auxin biosynthesis with increased temperatures has been reported in certain plant tissues. In contrast, we here found that under high temperature conditions, endogenous auxin levels specifically decreased in the developing anthers of barley and Arabidopsis. In addition, expression of the YUCCA auxin biosynthesis genes was repressed by increasing temperatures. Application of auxin completely reversed male sterility in both plant species. These findings suggest that tissue-specific auxin reduction is the primary cause of high temperature injury, which leads to the abortion of pollen development. Thus, the application of auxin may help sustain steady yields of crops despite future climate change.

  17. Floral phenology, secondary pollen presentation and pollination mechanism in Inula racemosa (Angiosperms: Asteraceae

    Directory of Open Access Journals (Sweden)

    P.A. Shabir

    2013-06-01

    Full Text Available Inula racemosa Hook. f. is protandrous, discharges pollen grains inside the anther tube and presents pollen secondarily onto the sweeping hairs of the style. The style and stigmatic branches present the yellow clumped pollen grains for pollination. This study describes floral functional morphology and phenology, anther dehiscence and pollen presentation, growth and behaviour of style during anthesis and pollination mechanism of I. racemosa. The species is entomophilous and is characterized by a highly asynchronous sexual phase. A large degree of asynchrony from floret to floret in a capitulum, and capitulum to capitulum in a plant, keeps the pollen dispersed for a longer duration. Two insect families were represented in the pollinator survey: Hymenoptera and Diptera. A significant correlation was observed between the number of capitula visited per bout and foraging time. We discuss morphological features of the ?owers which may enhance the pollen removal rate per bee visit and consequently cause a high visitation and pollination rate.

  18. High-temperature injury and auxin biosynthesis in microsporogenesis.

    Directory of Open Access Journals (Sweden)

    Atsushi eHigashitani

    2013-03-01

    Full Text Available Plant reproductive development is more sensitive than vegetative growth to many environmental stresses. With global warming, in particular, plant high temperature injury is becoming an increasingly serious problem. In wheat, barley, and various other commercially important crops, the early phase of anther development is especially susceptible to high temperatures. We recently demonstrated that high temperature causes cell-proliferation arrest and represses auxin signaling in a tissue-specific manner of the anther cells of barley and Arabidopsis. These phenomena were accompanied by comprehensive alterations in transcription including repression of cell-proliferation related genes and YUCCA auxin biosynthesis genes. Moreover, application of auxin completely improved the transcriptional alterations, the production of normal pollen grains, and seed setting rate under increasing temperatures. These denote that auxin, which has been used widely as potent and selective herbicides, is useful for the promotion of plant fertility and maintenance of crop yields under the global warming conditions.

  19. NOTES ON THE FLORAL MORPHOLOGY AND ANATOMY OF TESSMANNIANTHUS CARINATUS (MELASTOMATACEAE

    Directory of Open Access Journals (Sweden)

    RICARDO KRIEBEL

    2014-06-01

    Full Text Available This work reports the second collection of Tessmannianthus carinatus Almeda, a species previously known only from the type. Two flowering trees were encountered at the type locality of Cerro Jefe, Panama . Species in this genus are very rare and the colors and posture of fresh floral parts have seldom been observed and described. The first known images of flowers at anthesis are here provided. In addition, observations on the posture and color of the stamens were made, including dissections of a flower preserved in spirit, and scanning electron micrographs of the unusual anther apices. Lastly, anatomical sections were conducted of these flowers which revealed the presence of styloids in the hypanthium, anthers and styles. These crystals had only been reported from the wood of one species in the genus and their presence suggests a relationship to the tribes Astronieae and Henrietteeae.

  20. Pollen proteomics: from stress physiology to developmental priming.

    Science.gov (United States)

    Chaturvedi, Palak; Ghatak, Arindam; Weckwerth, Wolfram

    2016-06-01

    Pollen development and stress. In angiosperms, pollen or pollen grain (male gametophyte) is a highly reduced two- or three-cell structure which plays a decisive role in plant reproduction. Male gametophyte development takes place in anther locules where diploid sporophytic cells undergo meiotic division followed by two consecutive mitotic processes. A desiccated and metabolically quiescent form of mature pollen is released from the anther which lands on the stigma. Pollen tube growth takes place followed by double fertilization. Apart from its importance in sexual reproduction, pollen is also an interesting model system which integrates fundamental cellular processes like cell division, differentiation, fate determination, polar establishment, cell to cell recognition and communication. Recently, pollen functionality has been studied by multidisciplinary approaches which also include OMICS analyses like transcriptomics, proteomics and metabolomics. Here, we review recent advances in proteomics of pollen development and propose the process of developmental priming playing a key role to guard highly sensitive developmental processes.

  1. Microsporogenesis and flower development in Eucalyptus urophylla × E. tereticornis.

    Science.gov (United States)

    Yang, Jun; Kang, Xiangyang

    2015-03-01

    We compared microsporogenesis and flower development in Eucalyptus urophylla × E. tereticornis. In this study, although microsporogenesis and cytokinesis occurred simultaneously during meiosis of pollen mother cells, we observed a strong asynchronism in different anthers from a flower bud. The developmental period of microsporogenesis in anthers originated from the long thrum before the short thrum. Flower development was also asynchronous at different locations on a branch. The flower buds grew on the lower side of the branch and showed greater increases in diameter. In addition, we observed a relationship between microsporogenesis development and flower bud diameter growth. Generally, when the pachytene stage was first observed in a small single flower bud growing on top of a flowering branch, the remaining microsporogenesis stages (from diplotene to tetrad) in the whole branch occurred over the next 5-9 days. Thus, the start of microsporogenesis in E. urophylla × E. tereticornis could be determined, which may be applicable to future breeding studies.

  2. Nectar secretion in the flowers of comfrey (Symphytum officinale L. and nectar chemistry

    Directory of Open Access Journals (Sweden)

    Małgorzata Stpiczyńska

    2013-12-01

    Full Text Available Nectar secretion and nectar chemistry in the flowers of comfrey (Symphytum officinale L. were examined in the four stages of anthesis: large buds, before pollen exposure: II - freshy opened flowers with the beginning of anther dehiscence: III- completely opened flowers in the maximum of pollen exposure: lV- flowers at the final stage of anthesis, without pollen in the anthers. Individual flower stays fresh 2,5-3 days, on average. Disc-shaped nectaries of S.officinale are located at the base of the four-lobbed ovary. Nectar is released through the modified stomata. Start of nectar secretion was noted at the bud stage. Nectar volume, mass of nectar and sugars differed in the examined stages of anthesis and the biggest values were noted at the final stages. Dominant sugar in nectar was sucrose with smaller amounts of fructose and glucose. The presence of amino acids was also recorded.

  3. Sexual dimorphism in white campion: deletion on the Y chromosome results in a floral asexual phenotype

    International Nuclear Information System (INIS)

    Farbos, I.; Veuskens, J.; Vyskot, B.; Oliveira, M.; Hinnisdaels, S.; Aghmir, A.; Mouras, A.; Negrutiu, I.

    1999-01-01

    White campion is a dioecious plant with heteromorphic X and Y sex chromosomes. In male plants, a filamentous structure replaces the pistil, while in female plants the stamens degenerate early in flower development. Asexual (asx) mutants, cumulating the two developmental defects that characterize the sexual dimorphism in this species, were produced by gamma ray irradiation of pollen and screening in the M1 generation. The mutants harbor a novel type of mutation affecting an early function in sporogenous/parietal cell differentiation within the anther. The function is called stamen-promoting function (SPF). The mutants are shown to result from interstitial deletions on the Y chromosome. We present evidence that such deletions tentatively cover the central domain on the (p)-arm of the Y chromosome (Y2 region). By comparing stamen development in wild-type female and asx mutant flowers we show that they share the same block in anther development, which results in the production of vestigial anthers. The data suggest that the SPF, a key function(s) controlling the sporogenous/parietal specialization in premeiotic anthers, is genuinely missing in females (XX constitution). We argue that this is the earliest function in the male program that is Y-linked and is likely responsible for ''male dimorphism'' (sexual dimorphism in the third floral whorl) in white campion. More generally, the reported results improve our knowledge of the structural and functional organization of the Y chromosome and favor the view that sex determination in this species results primarily from a trigger signal on the Y chromosome (Y1 region) that suppresses female development. The default state is therefore the ancestral hermaphroditic state

  4. Production of engineered long-life and male sterile Pelargonium plants

    Directory of Open Access Journals (Sweden)

    García-Sogo Begoña

    2012-08-01

    Full Text Available Abstract Background Pelargonium is one of the most popular garden plants in the world. Moreover, it has a considerable economic importance in the ornamental plant market. Conventional cross-breeding strategies have generated a range of cultivars with excellent traits. However, gene transfer via Agrobacterium tumefaciens could be a helpful tool to further improve Pelargonium by enabling the introduction of new genes/traits. We report a simple and reliable protocol for the genetic transformation of Pelargonium spp. and the production of engineered long-life and male sterile Pelargonium zonale plants, using the pSAG12::ipt and PsEND1::barnase chimaeric genes respectively. Results The pSAG12::ipt transgenic plants showed delayed leaf senescence, increased branching and reduced internodal length, as compared to control plants. Leaves and flowers of the pSAG12::ipt plants were reduced in size and displayed a more intense coloration. In the transgenic lines carrying the PsEND1::barnase construct no pollen grains were observed in the modified anther structures, which developed instead of normal anthers. The locules of sterile anthers collapsed 3–4 days prior to floral anthesis and, in most cases, the undeveloped anther tissues underwent necrosis. Conclusion The chimaeric construct pSAG12::ipt can be useful in Pelargonium spp. to delay the senescence process and to modify plant architecture. In addition, the use of engineered male sterile plants would be especially useful to produce environmentally friendly transgenic plants carrying new traits by preventing gene flow between the genetically modified ornamentals and related plant species. These characteristics could be of interest, from a commercial point of view, both for pelargonium producers and consumers.

  5. Embryogenesis in Oak species. A review

    Directory of Open Access Journals (Sweden)

    Aranzazu Gomez-Garay

    2014-08-01

    Full Text Available Aim of study: A review on the propagation methods of four Quercus species, namely Q. suber, Q. robur, Q. ilex and Q. canariensis, through somatic embryogenesis and anther embryogenesis are presented.Area of study: The study comprises both Mediterranean and Atlantic oak species located in Spain.Material and Methods: Somatic embryogenesis was induced on immature zygotic embryos of diverse oak species, permitting the multiplication of half-sib families. Induction of haploid embryos and doubled haploids was assayed in both Q. suber and Q. ilex by temperature stress treatments of anthers containing late vacuolated microspores. The haploid origin of the anther embryos has been evaluated by quantitative nuclear DNA analysis through flow cytometry and by DNA microsatellite markers. Genetic transformation of cork oak has also been performed by means of Agrobacterium tumefaciens vectors. Proteomic analysis has been conducted to screen the diverse protein profiles followed by in vitro derived embryos during their development.Research highlights: Successful plant regeneration from both somatic and haploid embryos has been achieved. In the particular case of cork oak, doubled-haploid plants were obtained. Plantlets regenerated from selected parent trees through somatic embryogenesis were acclimated in the greenhouse and in the nursery, and were planted in an experimental plot in the field. Preliminary evaluation of the cork quality of the plants showed a good heritability correlation with the parent trees. This article revises the work of and is dedicated to Dr. M.A. Bueno, who devoted much of her professional life to the research on Biotechnology and Genetics of forest species, leading the Laboratory of Forest Biotechnology at the Spanish Institute of Agronomic Research (INIA.Key words: anther embryogenesis; microspore; pollen; Quercus canariensis; Quercus ilex; Quercus robur; Quercus suber; somatic embryogenesis. 

  6. DEVELOPMENT OF TOMATO HYBRIDS BASED ON FEMALE PARENTS FORMS WITH FUNCTIONAL MALE STERILITY

    Directory of Open Access Journals (Sweden)

    I. V. Uzun

    2016-01-01

    Full Text Available The rate of variability of functional male sterility (ps–2 depending on year of study, genotype and age of the plant is shown. The efficiency of the method of forced ejection of pollen from intact anthers to increase the degree of sterility is shown. The five tomato hybrids developed based on selected lines were submitted for the state variety trial of Moldova.

  7. De novo transcriptome assembly and comparative analysis of differentially expressed genes in Prunus dulcis Mill. in response to freezing stress.

    Directory of Open Access Journals (Sweden)

    Sadegh Mousavi

    Full Text Available Almond (Prunus dulcis Mill., one of the most important nut crops, requires chilling during winter to develop fruiting buds. However, early spring chilling and late spring frost may damage the reproductive tissues leading to reduction in the rate of productivity. Despite the importance of transcriptional changes and regulation, little is known about the almond's transcriptome under the cold stress conditions. In the current research, we used RNA-seq technique to study the response of the reproductive tissues of almond (anther and ovary to frost stress. RNA sequencing resulted in more than 20 million reads from anther and ovary tissues of almond, individually. About 40,000 contigs were assembled and annotated de novo in each tissue. Profile of gene expression in ovary showed significant alterations in 5,112 genes, whereas in anther 6,926 genes were affected by freezing stress. Around two thousands of these genes were common altered genes in both ovary and anther libraries. Gene ontology indicated the involvement of differentially expressed (DE genes, responding to freezing stress, in metabolic and cellular processes. qRT-PCR analysis verified the expression pattern of eight genes randomly selected from the DE genes. In conclusion, the almond gene index assembled in this study and the reported DE genes can provide great insights on responses of almond and other Prunus species to abiotic stresses. The obtained results from current research would add to the limited available information on almond and Rosaceae. Besides, the findings would be very useful for comparative studies as the number of DE genes reported here is much higher than that of any previous reports in this plant.

  8. De novo transcriptome assembly and comparative analysis of differentially expressed genes in Prunus dulcis Mill. in response to freezing stress.

    Science.gov (United States)

    Mousavi, Sadegh; Alisoltani, Arghavan; Shiran, Behrouz; Fallahi, Hossein; Ebrahimie, Esameil; Imani, Ali; Houshmand, Saadollah

    2014-01-01

    Almond (Prunus dulcis Mill.), one of the most important nut crops, requires chilling during winter to develop fruiting buds. However, early spring chilling and late spring frost may damage the reproductive tissues leading to reduction in the rate of productivity. Despite the importance of transcriptional changes and regulation, little is known about the almond's transcriptome under the cold stress conditions. In the current research, we used RNA-seq technique to study the response of the reproductive tissues of almond (anther and ovary) to frost stress. RNA sequencing resulted in more than 20 million reads from anther and ovary tissues of almond, individually. About 40,000 contigs were assembled and annotated de novo in each tissue. Profile of gene expression in ovary showed significant alterations in 5,112 genes, whereas in anther 6,926 genes were affected by freezing stress. Around two thousands of these genes were common altered genes in both ovary and anther libraries. Gene ontology indicated the involvement of differentially expressed (DE) genes, responding to freezing stress, in metabolic and cellular processes. qRT-PCR analysis verified the expression pattern of eight genes randomly selected from the DE genes. In conclusion, the almond gene index assembled in this study and the reported DE genes can provide great insights on responses of almond and other Prunus species to abiotic stresses. The obtained results from current research would add to the limited available information on almond and Rosaceae. Besides, the findings would be very useful for comparative studies as the number of DE genes reported here is much higher than that of any previous reports in this plant.

  9. A duplicated coxI gene is associated with cytoplasmic male sterility ...

    Indian Academy of Sciences (India)

    The new CMS line is comparable to euplasmic lines for almost all characters, except for flowers which bear slender, needle-like anthers with aborted pollen. Detailed Southern analysis revealed two copies of coxI gene in the CMS line. One copy, coxI-1 is similar to the coxI gene of B. juncea, whereas the second copy, coxI-2 ...

  10. Lower prevalence but similar fitness in a parasitic fungus at higher radiation levels near Chernobyl

    OpenAIRE

    Aguileta , Gabriela ,; Badouin , Helene; Hood , Michael E; Møller , Anders Pape; LE PRIEUR , STEPHANIE; Snirc , Alodie; Siguenza , Sophie; MOUSSEAU , TIMOTHY A.; Shykoff , Jacqui ,; Cuomo , Christina A.; Giraud , Tatiana

    2016-01-01

    International audience; Nuclear disasters at Chernobyl and Fukushima provide examples of effects of acute ionizing radiation on mutations that can affect the fitness and distribution of species. Here, we investigated the prevalence of Microbotryum lychnidis-dioicae, a pollinator-transmitted fungal pathogen of plants causing anther-smut disease in Chernobyl, its viability, fertility and karyotype variation, and the accumulation of nonsynonymous mutations in its genome. We collected diseased fl...

  11. The Threat Detection System that Cried Wolf: Reconciling Developers with Operators

    Science.gov (United States)

    2017-01-01

    January 2017, Vol. 24 No. 1 : 42–64 January 2017 them altogether ( Bliss , Gilson, & Deaton, 1995), potentially leading to disas- trous consequences. This...exclamation point ) are further examined manually by trained personnel (purple figure). In contrast, all items for which the system does not declare an...there are still time and opportunity to make adjust- ments. At that point , the PM can identify a concept of operations (CONOPS) in which the system

  12. People’s Republic of China Scientific Abstracts No. 179

    Science.gov (United States)

    1977-11-08

    No 2, April 1977 7 CHIH-WU HSUEH-PAO [ACTA BOTANICA SINICA] No 2, June 1977 22 I-CH’UAN HSUEH-PAO [ACTA GENETICA SINICA] No 1...of light energy. How luminescent molecules can store such great energy has not yet been ascertained. 11310 CSÖ: J*009 21 ACTA BOTANICA SINICA...and Peking Institute of Botany, Academia Sinica TITLE: "Studies on Maize Anther Culture" SOURCE: Peking CHIH-WU HSUEH-PAO [ACTA BOTANICA SINICA

  13. In vitro androgenetic cultures of Hyoscyamus niger L., H. albus L. and alkaloid content assay

    Directory of Open Access Journals (Sweden)

    Maria Wesołwska

    2014-01-01

    Full Text Available In vitro cultures of Hyoscyamus niger L. and H. albus L. anthers were initiated which resulted in obtaining androgenectic plants and callus cultures. The leaves of these pants and the callus cultures were subjected to analysis (TLC, GC for the presence of alkaloids, derivatives of tropane. In the studied material, alkaloids of different qualitative and quantitative composition from that of ground-grown plants were found.

  14. Download this PDF file

    African Journals Online (AJOL)

    2005-01-15

    Jan 15, 2005 ... Lemon yellow with very deep red base, pentamerous: shape obovate: 3.8-4.8 cm long and 2.2–3.8 cm wide. obovate. 0.3-0.4 cm long: filament red: anther yellow. Style light red; 1.8-. 2.1 cm long; stigma .... mudflats near the sea; also and on rocky grounds planted in front of houses, cultivated as ornamental ...

  15. Reproductive biology of Tinantia anomala (Torr. C.B. Clarke

    Directory of Open Access Journals (Sweden)

    Joanna Gębura

    2014-04-01

    Full Text Available Tinantia anomala (Torr. C.B. Clarke (Commelinaceae is an annual plant endemic to central Texas in the United States and Durango in northern Mexico. T. anomala has zygomorphic flowers with three different petals, androecium consists of six various stamens and gynoecium consists of three carpels. Furthermore in T. anomala’s flowers there are many staminal hairs (Faden 2006. Its semi-succulent, grass-like leaves emerge in late fall and remain green throughout the cold months. It grows rapidly in early spring and blooms mid-spring (from March to May. A few weeks later the fruits (capsules with four seeds usually appear. This entire cycle is usually completed by summer, when the plant has often turned yellow and limp. We studied T. anomala due to the occurrence of two types of strikingly different stamens occur in one flower. According to available literature, one type of the stamens (the upper one with smaller anthers produces sterile pollen grains which do not participate in fertilization but only attract insects. The other type, i.e. the lower stamens with bigger anthers can form abundant pollen grains used for pollination (Simpson et al. 1986. Our aim was to investigate type of pollination of T. anomala. Using many microscopic methods we were able to analyze and compare the morphology of two types of anthers and staminal hairs in T. anomala’s flowers. We also investigated this species in terms of development of its gametophytes. An embryo sac develops according to the type of Polygonum. Pollen grains develop during different ways depending on the chemical composition of each anther. We identified that the insects of Thysanoptera which preys on the withered flowers T. anomala could be responsible for pollination of this species under greenhouse condition.

  16. The coexistence of bicellular and tricellular pollen in Annona cherimola (Annonaceae): Implications for pollen evolution

    OpenAIRE

    Lora, Jorge; Herrero Romero, María; Hormaza Urroz, José Ignacio

    2009-01-01

    Most angiosperms release bicellular pollen. However, in about one-third of extant angiosperms, the second pollen mitosis occurs before anthesis such that pollen is tricellular upon release. The shift from bicellular to tricellular development has occurred several times independently, but its causes are largely unknown. In this work, we observed the coexistence of both kinds of pollen at anther dehiscence in Annona cherimola, a species that belongs to the basal angiosperm family Annonaceae. Ex...

  17. Pollen performance, cell number, and physiological state in the early-divergent angiosperm Annona cherimola Mill. (Annonaceae) are related to environmental conditions during the final stages of pollen development

    OpenAIRE

    Lora, Jorge; Herrero Romero, María; Hormaza Urroz, José Ignacio

    2012-01-01

    Pollen performance is an important determinant for fertilization success, but high variability in pollen behavior both between and within species occurs in different years and under varying environmental conditions. Annona cherimola, an early-divergent angiosperm, is a species that releases a variable ratio of bicellular and tricellular hydrated pollen at anther dehiscence depending on temperature. The presence of both bi- and tricellular types of pollen is an uncommon characteristic in angio...

  18. Physiological and proteomic approaches to address heat tolerance during anthesis in rice (Oryza sativa L.).

    Science.gov (United States)

    Jagadish, S V K; Muthurajan, R; Oane, R; Wheeler, T R; Heuer, S; Bennett, J; Craufurd, P Q

    2010-01-01

    Episodes of high temperature at anthesis, which in rice is the most sensitive stage to temperature, are expected to occur more frequently in future climates. The morphology of the reproductive organs and pollen number, and changes in anther protein expression, were studied in response to high temperature at anthesis in three rice (Oryza sativa L.) genotypes. Plants were exposed to 6 h of high (38 degrees C) and control (29 degrees C) temperature at anthesis and spikelets collected for morphological and proteomic analysis. Moroberekan was the most heat-sensitive genotype (18% spikelet fertility at 38 degrees C), while IR64 (48%) and N22 (71%) were moderately and highly heat tolerant, respectively. There were significant differences among the genotypes in anther length and width, apical and basal pore lengths, apical pore area, and stigma and pistil length. Temperature also affected some of these traits, increasing anther pore size and reducing stigma length. Nonetheless, variation in the number of pollen on the stigma could not be related to measured morphological traits. Variation in spikelet fertility was highly correlated (r=0.97, n=6) with the proportion of spikelets with > or = 20 germinated pollen grains on the stigma. A 2D-gel electrophoresis showed 46 protein spots changing in abundance, of which 13 differentially expressed protein spots were analysed by MS/MALDI-TOF. A cold and a heat shock protein were found significantly up-regulated in N22, and this may have contributed to the greater heat tolerance of N22. The role of differentially expressed proteins and morphology during anther dehiscence and pollination in shaping heat tolerance and susceptibility is discussed.

  19. Effects of Low Temperature Stress on Spikelet-Related Parameters during Anthesis in Indica–Japonica Hybrid Rice

    Directory of Open Access Journals (Sweden)

    Yanhua Zeng

    2017-08-01

    Full Text Available Poor spikelet fertility under low temperature (LT stress during anthesis limits the possibility of high yield potential in indica–japonica hybrid rice, leading to reduced stability of grain yield. However, the cause for it is still unclear. In this study, three indica–japonica hybrid rice cultivars, Yongyou9, Yongyou17 (both cold sensitive, and Yongyou538, and one japonica inbred rice cultivar, Zhejing88 (cold tolerant, were grown under LT (17°C and ambient temperature (AT (25°C during anthesis to test for their response with respect to spikelet fertility, pollen germination, and spikelet flowering. The results indicated that LT resulted in lower spikelet fertility in cold-sensitive cultivars than in cold-tolerant cultivars. Spikelet fertility was highly correlated with pollen germination on the stigma. The number of pollen grains and germinated pollen were higher in cold-tolerant cultivars than in cold-sensitive cultivars. Pollen fertility and pollen diameter were also higher in cold-tolerant cultivars, although the latter could achieve a high number of spikelets at anthesis in flowering patterns throughout the duration of LT stress. There were significant differences in anther width and volume between genotypes and treatments according to microscopic analyses, but no differences were observed in anther dehiscence. Moreover, variation in the number of pollen grains on stigmas and in spikelet fertility was not related to either the number of spikelets reaching anthesis or anther dehiscence. Overall, improved anther size, better pollen function, and higher spikelet fertility under LT stress were observed in cold-tolerant cultivars than in cold-sensitive cultivars. The results suggest that the increase in spikelet fertility is due to enhanced pollen germination rather than the number of spikelets reaching anthesis.

  20. Restoration of stamen development and production of functional pollen in an alloplasmic CMS tobacco line by ectopic expression of the Arabidopsis thaliana SUPERMAN gene.

    Science.gov (United States)

    Bereterbide, Agnès; Hernould, Michel; Farbos, Isabelle; Glimelius, Kristina; Mouras, Armand

    2002-03-01

    The alloplasmic male-sterile tobacco line Nta(rep)S, combining the nucleus of Nicotiana tabacum with the cytoplasm of Nicotiana repanda, exhibits cadastral-type anomalies due to a fusion of several stamens with the pistil. These anomalies share similarities with Arabidopsis superman mutants. SUPERMAN (SUP) is a cadastral gene controlling the boundary between whorls 3 (androecium) and 4 (gynoecium). Thus we hypothesized that the expression of the tobacco SUP orthologue might be impaired in the alloplasmic Nta(rep)S line, and that the deficiency could be complemented by the Arabidopsis SUP gene. Here we show that the ectopic expression of SUP in the alloplasmic male-sterile tobacco line Nta(rep)S significantly increases the frequency of flowers possessing free stamens, inducing the recovery of a proper structure for whorls 3 and 4. Furthermore, flowers of transgenic plants show a significant improvement of the morphology of stamens, and more particularly of the anthers, which are able to produce few but functional pollen. The data show that ectopic expression of Arabidopsis SUP reactivates the regulatory cascade of anther development. The plausible causes of the developmental defects of anthers in the alloplasmic male-sterile tobacco line are discussed in relation to the model of regulation of the Arabidopsis SUP gene.

  1. Sex-biased gene expression in dioecious garden asparagus (Asparagus officinalis).

    Science.gov (United States)

    Harkess, Alex; Mercati, Francesco; Shan, Hong-Yan; Sunseri, Francesco; Falavigna, Agostino; Leebens-Mack, Jim

    2015-08-01

    Sex chromosomes have evolved independently in phylogenetically diverse flowering plant lineages. The genes governing sex determination in dioecious species remain unknown, but theory predicts that the linkage of genes influencing male and female function will spur the origin and early evolution of sex chromosomes. For example, in an XY system, the origin of an active Y may be spurred by the linkage of female suppressing and male promoting genes. Garden asparagus (Asparagus officinalis) serves as a model for plant sex chromosome evolution, given that it has recently evolved an XX/XY sex chromosome system. In order to elucidate the molecular basis of gender differences and sex determination, we used RNA-sequencing (RNA-Seq) to identify differentially expressed genes between female (XX), male (XY) and supermale (YY) individuals. We identified 570 differentially expressed genes, and showed that significantly more genes exhibited male-biased than female-biased expression in garden asparagus. In the context of anther development, we identified genes involved in pollen microspore and tapetum development that were specifically expressed in males and supermales. Comparative analysis of genes in the Arabidopsis thaliana, Zea mays and Oryza sativa anther development pathways shows that anther sterility in females probably occurs through interruption of tapetum development before microspore meiosis. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  2. Cytological observations on microspore degeneration in cytoplasmic male sterility induced by gamma-irradiation in sugar beets

    International Nuclear Information System (INIS)

    Mikami, Tetsuo; Kinoshita, Toshiro; Takahashi, Man-emon

    1978-01-01

    Meiotic behaviours and the abnormalities of microsporogenesis were investigated in the complete sterile plants from four kinds of γ-line, which are the progenies of the male sterile mutants induced by γ-irradiations from H-2002, and these sterile plants were compared with those of H-19 MS with S cytoplasms in spontaneous origin. In the meiosis, there was no chromosomal abnormality showing the association of nine bivalents and the regular distribution of chromosomes irrespective of the source of cytoplasms. After the liberation of quartets, the conspicuous deformity of tapetal cells occurred in the complete sterile plants throughout all kinds of γ-line and H-19 MS. The modified type of anther tapeta was newly found in several plants from γ-114. The tapetal cells surrounding anther cavity enlarged vadially without the formation of tapetal plasmodium in this type. It is suggested that the different mechanism on pollen sterility has something to do with the cytoplasmic types which are responsible for the expression of complete sterile plants. The starch reaction in the middle layer and the endothecium of the anther also correlated with the type of tapetal abnormality. (Kobatake, H.)

  3. Effects of lighting and air movement on temperatures in reproductive organs of plants in a closed plant growth facility

    Science.gov (United States)

    Kitaya, Y.; Hirai, H.

    Temperature increases in plant reproductive organs such as anthers and stigmas could cause fertility impediments and thus produce sterile seeds under artificial lighting conditions without adequately controlled environments in closed plant growth facilities. There is a possibility such a situation could occur in Bioregenerative Life Support Systems under microgravity conditions in space because there will be little natural convective or thermal mixing. This study was conducted to determine the temperature of the plant reproductive organs as affected by illumination and air movement under normal gravitational forces on the earth and to make an estimation of the temperature increase in reproductive organs in closed plant growth facilities under microgravity in space. Thermal images of reproductive organs of rice and strawberry were captured using infrared thermography at air temperatures of 10 11 °C. Compared to the air temperature, temperatures of petals, stigmas and anthers of strawberry increased by 24, 22 and 14 °C, respectively, after 5 min of lighting at an irradiance of 160 W m-2 from incandescent lamps. Temperatures of reproductive organs and leaves of strawberry were significantly higher than those of rice. The temperatures of petals, stigmas, anthers and leaves of strawberry decreased by 13, 12, 13 and 14 °C, respectively, when the air velocity was increased from 0.1 to 1.0 ms-1. These results show that air movement is necessary to reduce the temperatures of plant reproductive organs in plant growth facilities.

  4. The role of stamens in ethylene production in Ipomoea nil

    International Nuclear Information System (INIS)

    Kiss, H.G.

    1989-01-01

    Ethylene production inhibits filament and corolla growth during young stages in flower development, and it promotes corolla unfolding and senescence in Ipomoea nil. Initial studies with the in vitro application of gibberellic acid (GA 3 ), demonstrated that decreased filament growth occurred when the anthers remained attached to the filaments during the young stages in development. The removal of the anthers from intact plants did not enhance filament growth until the synthesis of wound ethylene was inhibited by applied aminoethoxyvinylglycine (AVG) or cobalt chloride. It was hypothesized that the anthers were source tissues and that the filaments were transport vectors for the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) and indole-3-acetic acid (IAA) to regulate growth events in the various floral organs. To test this hypothesis, endogenous IAA and ACC and ethylene production were measured by enzyme linked immunosorbent assay (ELISA) or gas chromatography. The transport of 14 C-IAA and 14 C-ACC through filament segments and filaments within intact flower buds also was examined during flower development

  5. The bouquet of grapevine (Vitis vinifera L. cv. Cabernet Sauvignon) flowers arises from the biosynthesis of sesquiterpene volatiles in pollen grains

    Science.gov (United States)

    Martin, Diane M.; Toub, Omid; Chiang, Angela; Lo, Bernard C.; Ohse, Sebastian; Lund, Steven T.; Bohlmann, Jörg

    2009-01-01

    Terpenoid volatiles are important information molecules that enable pollinators to locate flowers and may protect reproductive tissues against pathogens or herbivores. Inflorescences of grapevine (Vitis vinifera L.) are composed of tiny green flowers that produce an abundance of sesquiterpenoid volatiles. We demonstrate that male flower parts of grapevines are responsible for sesquiterpenoid floral scent formation. We describe temporal and spatial patterns of biosynthesis and release of floral volatiles throughout the blooming of V. vinifera L. cv. Cabernet Sauvignon. The biosynthesis of sesquiterpene volatiles, which are emitted with a light-dependent diurnal pattern early in the morning at prebloom and bloom, is localized to anthers and, more specifically, within the developing pollen grains. Valencene synthase (VvValCS) enzyme activity, which produces the major sesquiterpene volatiles of grapevine flowers, is present in anthers. VvValCS transcripts are most abundant in flowers at prebloom stages. Western blot analysis identified VvValCS protein in anthers, and in situ immunolabeling located VvValCS protein in pollen grains during bloom. Histochemical staining, as well as immunolabeling analysis by fluorescent microscopy and transmission electron microscopy, indicated that VvValCS localizes close to lipid bodies within the maturing microspore. PMID:19359488

  6. Development of the gametophytes, flower, and floral vasculature in Dichorisandra thyrsiflora (Commelinaceae).

    Science.gov (United States)

    Hardy, C R; Stevenson, D W; Kiss, H G

    2000-09-01

    The flowers of Dichorisandra thyrsiflora (Commelinaceae) are monosymmetric and composed of three sepals, three petals, six stamens, and three connate carpels. The anthers are poricidal and possess a wall of five cell layers (tapetum included). This type of anther wall, not previously observed in the Commelinaceae, is developmentally derived from the monocotyledonous type via an additional periclinal division and the persistence of the middle layers through anther dehiscence. Secondary endothecial thickenings develop in the cells of the two middle layers only. The tapetum is periplasmodial and contains raphides. Microsporogenesis is successive and yields both decussate and isobilateral tetrads. Pollen is shed as single binucleate grains. The gynoecium is differentiated into a globose ovary, hollow elongate style, and trilobed papillate stigma. Each locule contains six to eight hemianatropous to slightly campylotropous crassinucellar ovules with axile (submarginal) placentation. The ovules are bitegmic with a slightly zig-zag micropyle. Megagametophyte development is of the Polygonum type. The mature megagametophyte consists of an egg apparatus and fusion nucleus; the antipodals having degenerated. The floral vasculature is organized into an outer and inner system of bundles in the pedicel. The outer system becomes ventral carpellary bundles. All other floral vascular traces originate from the inner system.

  7. Embryology of Ageratum conyzoides L. and A. fastigiatum R.M. King & H. Rob. (Asteraceae

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    Rafael de Oliveira Franca

    2015-03-01

    Full Text Available Ageratum has a complex circumscription, and recent studies have indicated its polyphyletism. The genus has been placed in the tribe Eupatorieae whose embryology is not fully known. Embryological data are conservative and important indicators of phylogenetic relationships and can improve family relationships. This study presents, for the first time in Eupatorieae, embryological data for Ageratum conyzoides and A. fastigiatum. Both species have common features of the family such as a unitegmic anatropous ovule, basal placentation, secretory tapetum, Polygonum megagametophyte, and Asterad embryogenesis. The data obtained reinforce the heterogeneity of the family embryology and show, for the first time, the anther wall development of the monocotyledonous type for Asteraceae. The species studied show also differences between themselves. A. conyzoides has bisporangiated and introrse anthers, conspicuous pappus, and cypselae with trichomes on the ribs, whereas A. fastigiatum has tetrasporangiate and latrorse anthers, pappus absent at maturity, and glabrous cypselae. The data presented support recent phylogenetic molecular studies, suggesting the replacement of A. fastigiatum to another genus along with Gyptidinae.

  8. Association Study Reveals Novel Genes Related to Yield and Quality of Fruit in Cape Gooseberry (Physalis peruviana L.

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    Francy L. García-Arias

    2018-03-01

    Full Text Available Association mapping has been proposed as an efficient approach to assist plant breeding programs to investigate the genetic basis of agronomic traits. In this study, we evaluated 18 traits related to yield, (FWP, NF, FWI, and FWII, fruit size-shape (FP, FA, MW, WMH, MH, HMW, DI, FSI, FSII, OVO, OBO, and fruit quality (FIR, CF, and SST, in a diverse collection of 100 accessions of Physalis peruviana including wild, landraces, and anther culture derived lines. We identified seven accessions with suitable traits: fruit weight per plant (FWP > 7,000 g/plant and cracked fruits (CF < 4%, to be used as parents in cape gooseberry breeding program. In addition, the accessions were also characterized using Genotyping By Sequencing (GBS. We discovered 27,982 and 36,142 informative SNP markers based on the alignment against the two cape gooseberry references transcriptomes. Besides, 30,344 SNPs were identified based on alignment to the tomato reference genome. Genetic structure analysis showed that the population could be divided into two or three sub-groups, corresponding to landraces-anther culture and wild accessions for K = 2 and wild, landraces, and anther culture plants for K = 3. Association analysis was carried out using a Mixed Linear Model (MLM and 34 SNP markers were significantly associated. These results reveal the basis of the genetic control of important agronomic traits and may facilitate marker-based breeding in P. peruviana.

  9. Association Study Reveals Novel Genes Related to Yield and Quality of Fruit in Cape Gooseberry (Physalis peruviana L.).

    Science.gov (United States)

    García-Arias, Francy L; Osorio-Guarín, Jaime A; Núñez Zarantes, Victor M

    2018-01-01

    Association mapping has been proposed as an efficient approach to assist plant breeding programs to investigate the genetic basis of agronomic traits. In this study, we evaluated 18 traits related to yield, (FWP, NF, FWI, and FWII), fruit size-shape (FP, FA, MW, WMH, MH, HMW, DI, FSI, FSII, OVO, OBO), and fruit quality (FIR, CF, and SST), in a diverse collection of 100 accessions of Physalis peruviana including wild, landraces, and anther culture derived lines. We identified seven accessions with suitable traits: fruit weight per plant (FWP) > 7,000 g/plant and cracked fruits (CF) cape gooseberry breeding program. In addition, the accessions were also characterized using Genotyping By Sequencing (GBS). We discovered 27,982 and 36,142 informative SNP markers based on the alignment against the two cape gooseberry references transcriptomes. Besides, 30,344 SNPs were identified based on alignment to the tomato reference genome. Genetic structure analysis showed that the population could be divided into two or three sub-groups, corresponding to landraces-anther culture and wild accessions for K = 2 and wild, landraces, and anther culture plants for K = 3. Association analysis was carried out using a Mixed Linear Model (MLM) and 34 SNP markers were significantly associated. These results reveal the basis of the genetic control of important agronomic traits and may facilitate marker-based breeding in P. peruviana .

  10. Characterization of leaf, flower, and pod morphology among Vietnamese cocoa varieties (Theobroma cacao L.)

    International Nuclear Information System (INIS)

    Viet, L.T.; Hang, P.T.; Everaert, H.; Rottiers, H.; Dung, T.N

    2016-01-01

    This study examined the morphological traits of 63 cocoa varieties that have been imported and cultivated in Vietnam. These cocoa varieties were collected from five regions in Southern Vietnam and were classified into three groups based on their phylogenetic relationships. Their morphological features were individually evaluated and analysed. This included leaf characteristics (leaf and stem anatomy) and flower features (ligule shape, anther number, pollen, stamen and ovule, fruit, seed). The results of this study showed a large variation across all morphological characteristics of the evaluated cocoa varieties. The Vietnamese cocoa flower showed a diversity of morphological characteristics including five shapes of ligule (oval, broad, deltoid, elliptic and sub-lanceolate) and each stamen also has a bilobed anther with the exception of trilobed anther for TD11. Furthermore, the shape of pollen grains was found homogeneous in all 63 varieties. The colour of the stamens and ovules was purple and white respectively for all examined samples. Three kinds of fruit shapes were identified, namely Angoleta, Amelonado and Cundeamor, and these were of various colours. Additionally, an anatomical analysis on the midrib structure of the leaves from the 63 varieties showed the highest similarity, likewise the stem structure. The colour of young leaves was observed as being green and red. This is the primary research that scrutinizes the morphological biodiversity of Vietnamese cocoa varieties during the three-decade development of the Vietnam cocoa project. The results have a practical applications for cocoa cross-breeding and botanical taxonomy. (author)

  11. The genetic architecture of traits associated with the evolution of self-pollination in Mimulus.

    Science.gov (United States)

    Fishman, Lila; Beardsley, Paul M; Stathos, Angela; Williams, Charles F; Hill, Jeffrey P

    2015-01-01

    Quantitative trait locus (QTL) mapping is a first step toward understanding the genetic basis of adaptive evolution and may also reveal reproductive incompatibilities unique to hybrids. In plants, the shift from outcrossing to self-pollination is common, providing the opportunity for comparisons of QTL architecture among parallel evolutionary transitions. We used QTL mapping in hybrids between the bee-pollinated monkeyflower Mimulus lewisii and the closely related selfer Mimulus parishii to determine the genetic basis of divergence in floral traits and flowering time associated with mating-system evolution, and to characterize hybrid anther sterility. We found a moderately polygenic and highly directional basis for floral size evolution, suggesting adaptation from standing variation or in pursuit of a moving optimum, whereas only a few major loci accounted for substantial flowering-time divergence. Cytonuclear incompatibilities caused hybrid anther sterility, confounding estimation of reproductive organ QTLs. The genetic architecture of floral traits associated with selfing in M. parishii was primarily polygenic, as in other QTL studies of this transition, but in contrast to the previously characterized oligogenic basis of a pollinator shift in close relatives. Hybrid anther sterility appeared parallel at the molecular level to previously characterized incompatibilities, but also raised new questions about cytonuclear co-evolution in plants. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  12. Scanning electron microscopy investigations regarding Adonis vernalis L. flower morphology

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    Irina Neta GOSTIN

    2009-11-01

    Full Text Available The floral morphology of Adonis vernalis L. was observed with a scanning electron microscope (SEM. The investigations are important to clarify some taxonomical problems and also could provide useful diagnostic elements for the identification of this medicinal plant in powdered materials. All floral organs are initiated spirally and centripetally and develop centripetally. The petals (8-12 are shorter than the sepals (5-6 in early developmental stages. The petals are disposed on spiral (with 3-4 whorls. The stamens (numerous are unbranched and reach maturity centripetally; they are free of the perianth. The anther walls consisting of a single layer epidermis in the anther wall surrounding the sporagenous tissue, one row of endothecium, two to four rows of middle layer and one row of tapetum layer. In the anther walls, the tapetal cells, by glandular type, persist later in ontogenesis. Pollen grains are tricolpate with echinate surface. The gynoecium is multiple, apocarpous with distinct carpels. The carpels are ascidiate from the beginning. At the base of each carpel, numerousness short, unicellular, trichomes are present. The stigma differentiates as two crests along the ventral slit of the ovary. Each carpel contains a single ovule inside the ovary cavity. The mature ovule is anatropous, with two integuments. It is almost parallel to the funicle.

  13. Pollen production in selected species of anemophilous plants

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    Krystyna Piotrowska

    2012-12-01

    Full Text Available In the study, structural features of flowers of the following allergenic plant species were analysed: Betula verrucosa, Secale cereale, Rumex acetosella, Plantago major and Artemisia vulgaris. Pollen production was established by calculating the number of pollen grains produced by the stamen, flower and inflorescence. The dates of occurrence and pollen grains concentration in the air of Lublin were determined. A positive correlation was found between the length of anthers and the number of pollen grains produced. The largest number of pollen grains per anther is produced by Secale cereale (22 360, whereas the smallest one by Plantago major (5 870. The other species produced intermediate numbers of pollen grains in the anther: Betula verrucosa - 11 160, Rumex acetosella - 10 850, Artemisia vulgaris - 9 580. The birch pollen season in Lublin lasts about a month, and pollen of this taxon reaches the highest airborne concentrations among the studied taxa. Low values of pollen concentrations are characteristic for rye and plantain, whereas slightly higher values are recorded for sorrel pollen. Mugwort pollen reaches high concentrations which are noted at the beginning of August.

  14. Rice improvement, involving altered flower structure more suitable to cross-pollination, using in vitro culture in combination with mutagenesis

    International Nuclear Information System (INIS)

    Min, S.K.

    1998-01-01

    Anther and somatic tissue culture in combination with mutagenesis were carried out to evaluate the efficiency of different mutagenic treatments of various in vitro culture materials, and to obtain some promising variants for rice improvement. Results indicated that in japonica rice radiation treatment of dry seeds and young panicles influenced the percentage of green plantlets regeneration from anther culture. Both treatments increased significantly the percentage of regenerated green plantlets in comparison with the control. Irradiation with 30 Gy of rice callus increased also the percentage of regenerated green plantlets. For indica rice, the combination of the suitable dose of gamma rays irradiation on seeds and an improved medium, increased the percentage of callus induction. This approach made it possible to use anther culture in indica rice breeding. Somatic tissue cultures combined with radiation-induced mutagenesis led to the development of a number of promising mutants including some new cytoplasm-nucleus interacting male-sterile lines with almost 100% stigma exertion. Their development would be of practical significance for increasing the genetic diversity for production of hybrid rice. (author)

  15. Chimeric calcium/calmodulin-dependent protein kinase in tobacco: differential regulation by calmodulin isoforms

    Science.gov (United States)

    Liu, Z.; Xia, M.; Poovaiah, B. W.

    1998-01-01

    cDNA clones of chimeric Ca2+/calmodulin-dependent protein kinase (CCaMK) from tobacco (TCCaMK-1 and TCCaMK-2) were isolated and characterized. The polypeptides encoded by TCCaMK-1 and TCCaMK-2 have 15 different amino acid substitutions, yet they both contain a total of 517 amino acids. Northern analysis revealed that CCaMK is expressed in a stage-specific manner during anther development. Messenger RNA was detected when tobacco bud sizes were between 0.5 cm and 1.0 cm. The appearance of mRNA coincided with meiosis and became undetectable at later stages of anther development. The reverse polymerase chain reaction (RT-PCR) amplification assay using isoform-specific primers showed that both of the CCaMK mRNAs were expressed in anther with similar expression patterns. The CCaMK protein expressed in Escherichia coli showed Ca2+-dependent autophosphorylation and Ca2+/calmodulin-dependent substrate phosphorylation. Calmodulin isoforms (PCM1 and PCM6) had differential effects on the regulation of autophosphorylation and substrate phosphorylation of tobacco CCaMK, but not lily CCaMK. The evolutionary tree of plant serine/threonine protein kinases revealed that calmodulin-dependent kinases form one subgroup that is distinctly different from Ca2+-dependent protein kinases (CDPKs) and other serine/threonine kinases in plants.

  16. Cell Death and Cell Cycle Arrest of Silene latifolia Stamens and Pistils After Microbotryum lychnidis-dioicae Infection.

    Science.gov (United States)

    Kawamoto, Hiroki; Yamanaka, Kaori; Koizumi, Ayako; Hirata, Aiko; Kawano, Shigeyuki

    2017-02-01

    Mechanisms of suppression of pistil primordia in male flowers and of stamen primordia in female flowers differ in diclinous plants. In this study, we investigated how cell death and cell cycle arrest are related to flower organ formation in Silene latifolia. Using in situ hybridization and a TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) assay, we detected both cell cycle arrest and cell death in suppressed stamens of female flowers and suppressed pistils of male flowers in S. latifolia. In female flowers infected with Microbotryum lychnidis-dioicae, developmental suppression of stamens is released, and cell cycle arrest and cell death do not occur. Smut spores are formed in S. latifolia anthers infected with M. lychnidis-dioicae, followed by cell death in the endothelium, middle layer, tapetal cells and pollen mother cells. Cell death is difficult to detect using a fluorescein isothiocyanate-labeled TUNEL assay due to strong autofluorescence in the anther. We therefore combined a TUNEL assay in an infrared region with transmission electron microscopy to detect cell death in anthers. We show that following infection by M. lychnidis-dioicae, a TUNEL signal was not detected in the endothelium, middle layer or pollen mother cells, and cell death with outflow of cell contents, including the nucleoplast, was observed in tapetal cells. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  17. Systematics of the southern African genus Ixia (Iridaceae. 2. The filiform-leaved I. capillaris complex

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    P. Goldblatt

    2008-08-01

    Full Text Available Field study and associated examination of herbarium specimens of the filiform-leaved species of section Morphixia o f the South African genus Ixia L. have resulted in an increase in the number of species with this derived leaf type.  Ixia capillaris and  I. pauciflora have until now been the only species with such leaves and they have not been regarded as immediately related in past accounts of the genus. The two foliage leaves, typically less than 2 mm w ide, with a leathery to succulent texture, and lacking a raised central vein or margins, are specialized in the genus. Associated finely fibrous corm tunics, spikes of 1-3 flowers, and when present, short, thread-like lateral branches, usually bearing 1 or 2 flowers, provide supporting evidence that the group is monophyletic.  I. capillaris as interpreted until now. comprises four species, three of them new and described here, and the large-flowered I. pauciflora includes two species, one of these described here. While I. capillaris has a branched stem, radially symmetric flowers with a penanth tube (4—5—7(—8 mm long, tepals 11-15 mm long and thus substantially exceeding the tube, filaments typically exserted 1-2 mm. and anthers (3—4—5 mm long. I. exiliflora has a tube 8-10 mm long and ± as long as the tepals, included filaments, and anthers 3.5—4.0 mm long. The new  I. dieramoides also has included filaments but a perianth tube 13—18(—22 mm long and tepals 11-18 mm long. A third new species. I. reclinata has large flowers with a tube 13-15 mm long, tepals 16-21 mm long, and unilateral, decimate stamens with the filaments exserted 8-10 mm. and anthers 4-5 mm long. Typical  I. pauciflora has flowers with unilateral stamens and filaments exserted 2-6 mm from the flower and anthers prominently displayed, but specimens until now included in that species w ith short, included filaments 3-5 mm long and anthers half included in the tube, are here regarded as I. dieramoides. The I

  18. Plant and Floret Growth at Distinct Developmental Stages During the Stem Elongation Phase in Wheat

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    Zifeng Guo

    2018-03-01

    Full Text Available Floret development is critical for grain setting in wheat (Triticum aestivum, but more than 50% of grain yield potential (based on the maximum number of floret primordia is lost during the stem elongation phase (SEP, from the terminal spikelet stage to anthesis. Dynamic plant (e.g., leaf area, plant height and floret (e.g., anther and ovary size growth and its connection with grain yield traits (e.g., grain number and width are not clearly understood. In this study, for the first time, we dissected the SEP into seven stages to investigate plant (first experiment and floret (second experiment growth in greenhouse- and field-grown wheat. In the first experiment, the values of various plant growth trait indices at different stages were generally consistent between field and greenhouse and were independent of the environment. However, at specific stages, some traits significantly differed between the two environments. In the second experiment, phenotypic and genotypic similarity analysis revealed that grain number and size corresponded closely to ovary size at anthesis, suggesting that ovary size is strongly associated with grain number and size. Moreover, principal component analysis (PCA showed that the top six principal components PCs explained 99.13, 98.61, 98.41, 98.35, and 97.93% of the total phenotypic variation at the green anther, yellow anther, tipping, heading, and anthesis stages, respectively. The cumulative variance explained by the first PC decreased with floret growth, with the highest value detected at the green anther stage (88.8% and the lowest at the anthesis (50.09%. Finally, ovary size at anthesis was greater in wheat accessions with early release years than in accessions with late release years, and anther/ovary size shared closer connections with grain number/size traits at the late vs. early stages of floral development. Our findings shed light on the dynamic changes in plant and floret growth-related traits in wheat and the

  19. The maize tapetum employs diverse mechanisms to synthesize and store proteins and flavonoids and transfer them to the pollen surface.

    Science.gov (United States)

    Li, Yubing; Suen, Der Fen; Huang, Chien-Yu; Kung, Shung-Yee; Huang, Anthony H C

    2012-04-01

    In anthers, the tapetum synthesizes and stores proteins and flavonoids, which will be transferred to the surface of adjacent microspores. The mechanism of synthesis, storage, and transfer of these pollen-coat materials in maize (Zea mays) differs completely from that reported in Arabidopsis (Arabidopsis thaliana), which stores major pollen-coat materials in tapetosomes and elaioplasts. On maize pollen, three proteins, glucanase, xylanase, and a novel protease, Zea mays pollen coat protease (ZmPCP), are predominant. During anther development, glucanase and xylanase transcripts appeared at a mid developmental stage, whereas protease transcript emerged at a late developmental stage. Protease and xylanase transcripts were present only in the anther tapetum of the plant, whereas glucanase transcript was distributed ubiquitously. ZmPCP belongs to the cysteine protease family but has no closely related paralogs. Its nascent polypeptide has a putative amino-terminal endoplasmic reticulum (ER)-targeting peptide and a propeptide. All three proteins were synthesized in the tapetum and were present on mature pollen after tapetum death. Electron microscopy of tapetum cells of mid to late developmental stages revealed small vacuoles distributed throughout the cytoplasm and numerous secretory vesicles concentrated near the locular side. Immunofluorescence microscopy and subcellular fractionation localized glucanase in ER-derived vesicles in the cytoplasm and the wall facing the locule, xylanase in the cytosol, protease in vacuoles, and flavonoids in subdomains of ER rather than in vacuoles. The nonoverlapping subcellular locations of the three proteins and flavonoids indicate distinct modes of their storage in tapetum cells and transfer to the pollen surface, which in turn reflect their respective functions in tapetum cells or the pollen surface.

  20. Isolation and characterization of the Jatropha curcas APETALA1 (JcAP1) promoter conferring preferential expression in inflorescence buds.

    Science.gov (United States)

    Tao, Yan-Bin; He, Liang-Liang; Niu, Longjian; Xu, Zeng-Fu

    2016-08-01

    The 1.5 kb JcAP1 promoter from the biofuel plant Jatropha curcas is predominantly active in the inflorescence buds of transgenic plants, in which the -1313/-1057 region is essential for maintaining the activity. Arabidopsis thaliana APETALA1 (AP1) is a MADS-domain transcription factor gene that functions primarily in flower development. We isolated a homolog of AP1 from Jatropha curcas (designated JcAP1), which was shown to exhibit flower-specific expression in Jatropha. JcAP1 is first expressed in inflorescence buds and continues to be primarily expressed in the sepals. We isolated a 1.5 kb JcAP1 promoter and evaluated its activity in transgenic Arabidopsis and Jatropha using the β-glucuronidase (GUS) reporter gene. In transgenic Arabidopsis and Jatropha, the inflorescence buds exhibited notable GUS activity, whereas the sepals did not. Against expectations, the JcAP1 promoter was active in the anthers of Arabidopsis and Jatropha and was highly expressed in Jatropha seeds. An analysis of promoter deletions in transgenic Arabidopsis revealed that deletion of the -1313/-1057 region resulted in loss of JcAP1 promoter activity in the inflorescence buds and increased activity in the anthers. These results suggested that some regulatory sequences in the -1313/-1057 region are essential for maintaining promoter activity in inflorescence buds and can partly suppress activity in the anthers. Based on these findings, we hypothesized that other elements located upstream of the 1.5 kb JcAP1 promoter may be required for flower-specific activation. The JcAP1 promoter characterized in this study can be used to drive transgene expression in both the inflorescence buds and seeds of Jatropha.

  1. De Novo Assembly and Transcriptome Analysis of Wheat with Male Sterility Induced by the Chemical Hybridizing Agent SQ-1.

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    Qidi Zhu

    Full Text Available Wheat (Triticum aestivum L., one of the world's most important food crops, is a strictly autogamous (self-pollinating species with exclusively perfect flowers. Male sterility induced by chemical hybridizing agents has increasingly attracted attention as a tool for hybrid seed production in wheat; however, the molecular mechanisms of male sterility induced by the agent SQ-1 remain poorly understood due to limited whole transcriptome data. Therefore, a comparative analysis of wheat anther transcriptomes for male fertile wheat and SQ-1-induced male sterile wheat was carried out using next-generation sequencing technology. In all, 42,634,123 sequence reads were generated and were assembled into 82,356 high-quality unigenes with an average length of 724 bp. Of these, 1,088 unigenes were significantly differentially expressed in the fertile and sterile wheat anthers, including 643 up-regulated unigenes and 445 down-regulated unigenes. The differentially expressed unigenes with functional annotations were mapped onto 60 pathways using the Kyoto Encyclopedia of Genes and Genomes database. They were mainly involved in coding for the components of ribosomes, photosynthesis, respiration, purine and pyrimidine metabolism, amino acid metabolism, glutathione metabolism, RNA transport and signal transduction, reactive oxygen species metabolism, mRNA surveillance pathways, protein processing in the endoplasmic reticulum, protein export, and ubiquitin-mediated proteolysis. This study is the first to provide a systematic overview comparing wheat anther transcriptomes of male fertile wheat with those of SQ-1-induced male sterile wheat and is a valuable source of data for future research in SQ-1-induced wheat male sterility.

  2. The Small-RNA Profiles of Almond (Prunus dulcis Mill. Reproductive Tissues in Response to Cold Stress.

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    Marzieh Karimi

    Full Text Available Spring frost is an important environmental stress that threatens the production of Prunus trees. However, little information is available regarding molecular response of these plants to the frost stress. Using high throughput sequencing, this study was conducted to identify differentially expressed miRNAs, both the conserved and the non-conserved ones, in the reproductive tissues of almond tolerant H genotype under cold stress. Analysis of 50 to 58 million raw reads led to identification of 174 unique conserved and 59 novel microRNAs (miRNAs. Differential expression pattern analysis showed that 50 miRNA families were expressed differentially in one or both of almond reproductive tissues (anther and ovary. Out of these 50 miRNA families, 12 and 15 displayed up-regulation and down-regulation, respectively. The distribution of conserved miRNA families indicated that miR482f harbor the highest number of members. Confirmation of miRNAs expression patterns by quantitative real- time PCR (qPCR was performed in cold tolerant (H genotype alongside a sensitive variety (Sh12 genotype. Our analysis revealed differential expression for 9 miRNAs in anther and 3 miRNAs in ovary between these two varieties. Target prediction of miRNAs followed by differential expression analysis resulted in identification of 83 target genes, mostly transcription factors. This study comprehensively catalogued expressed miRNAs under different temperatures in two reproductive tissues (anther and ovary. Results of current study and the previous RNA-seq study, which was conducted in the same tissues by our group, provide a unique opportunity to understand the molecular basis of responses of almond to cold stress. The results can also enhance the possibility for gene manipulation to develop cold tolerant plants.

  3. The Small-RNA Profiles of Almond (Prunus dulcis Mill.) Reproductive Tissues in Response to Cold Stress.

    Science.gov (United States)

    Karimi, Marzieh; Ghazanfari, Farahnaz; Fadaei, Adeleh; Ahmadi, Laleh; Shiran, Behrouz; Rabei, Mohammad; Fallahi, Hossein

    2016-01-01

    Spring frost is an important environmental stress that threatens the production of Prunus trees. However, little information is available regarding molecular response of these plants to the frost stress. Using high throughput sequencing, this study was conducted to identify differentially expressed miRNAs, both the conserved and the non-conserved ones, in the reproductive tissues of almond tolerant H genotype under cold stress. Analysis of 50 to 58 million raw reads led to identification of 174 unique conserved and 59 novel microRNAs (miRNAs). Differential expression pattern analysis showed that 50 miRNA families were expressed differentially in one or both of almond reproductive tissues (anther and ovary). Out of these 50 miRNA families, 12 and 15 displayed up-regulation and down-regulation, respectively. The distribution of conserved miRNA families indicated that miR482f harbor the highest number of members. Confirmation of miRNAs expression patterns by quantitative real- time PCR (qPCR) was performed in cold tolerant (H genotype) alongside a sensitive variety (Sh12 genotype). Our analysis revealed differential expression for 9 miRNAs in anther and 3 miRNAs in ovary between these two varieties. Target prediction of miRNAs followed by differential expression analysis resulted in identification of 83 target genes, mostly transcription factors. This study comprehensively catalogued expressed miRNAs under different temperatures in two reproductive tissues (anther and ovary). Results of current study and the previous RNA-seq study, which was conducted in the same tissues by our group, provide a unique opportunity to understand the molecular basis of responses of almond to cold stress. The results can also enhance the possibility for gene manipulation to develop cold tolerant plants.

  4. The estimation of Adonis vernalis populations in chosen patches of Lublin Upland

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    Bożena Denisow

    2012-12-01

    Full Text Available The number of Adonis vernalis populations, their size and abundance in xerothermic communities of the Lublin Upland have decreased significantly in the last 40-50 years, which indicates that there is a real risk of species extinction in the studied area. The paper is an attempt to indicate the possible factors which influence the decrease of Adonis vernalis populations. Detailed studies were carried out in six sites differing habitat conditions, land use and the size of Adonis vernalis populations. Observations were made of the abundance of blooming and the number of anthers per flower. The ability for reproduction was estimated indirectly by the mass of pollen delivered and its biological value. The populations of Adonis vernalis differ in number of anthers per flower (94.4 - 131.5, on average, the mass of pollen delivered (0.83 mg - 3.18 mg per 100 anthers, on average, the biological value of pollen and the size of pollen grains. Generally, stronger populations were characterized by better quality and a higher quantity of pollen. Potential energy of pollen in flowers from Pliszczyn and Łabunie was 69-72%, compared to 36%-47% in the remaining populations. Grass burning did not cause a reduction of potential biological value of Adonis vernalis pollen. Xerothermic swards in Pliszczyn and Kąty regularly burnt developed strong, most abundant populations of Adonis vernalis with favorable pollen. The development of the shrub layer, if it is out of control, stands in the way of satisfactory reproduction of halophilous Adonis vernalis.

  5. Comparative and Evolutionary Analysis of Grass Pollen Allergens Using Brachypodium distachyon as a Model System.

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    Akanksha Sharma

    Full Text Available Comparative genomics have facilitated the mining of biological information from a genome sequence, through the detection of similarities and differences with genomes of closely or more distantly related species. By using such comparative approaches, knowledge can be transferred from the model to non-model organisms and insights can be gained in the structural and evolutionary patterns of specific genes. In the absence of sequenced genomes for allergenic grasses, this study was aimed at understanding the structure, organisation and expression profiles of grass pollen allergens using the genomic data from Brachypodium distachyon as it is phylogenetically related to the allergenic grasses. Combining genomic data with the anther RNA-Seq dataset revealed 24 pollen allergen genes belonging to eight allergen groups mapping on the five chromosomes in B. distachyon. High levels of anther-specific expression profiles were observed for the 24 identified putative allergen-encoding genes in Brachypodium. The genomic evidence suggests that gene encoding the group 5 allergen, the most potent trigger of hay fever and allergic asthma originated as a pollen specific orphan gene in a common grass ancestor of Brachypodium and Triticiae clades. Gene structure analysis showed that the putative allergen-encoding genes in Brachypodium either lack or contain reduced number of introns. Promoter analysis of the identified Brachypodium genes revealed the presence of specific cis-regulatory sequences likely responsible for high anther/pollen-specific expression. With the identification of putative allergen-encoding genes in Brachypodium, this study has also described some important plant gene families (e.g. expansin superfamily, EF-Hand family, profilins etc for the first time in the model plant Brachypodium. Altogether, the present study provides new insights into structural characterization and evolution of pollen allergens and will further serve as a base for their

  6. High species richness of native pollinators in Brazilian tomato crops

    Directory of Open Access Journals (Sweden)

    C. M. Silva-Neto

    Full Text Available Abstract Pollinators provide an essential service to natural ecosystems and agriculture. In tomatoes flowers, anthers are poricidal, pollen may drop from their pore when flowers are shaken by the wind. However, bees that vibrate these anthers increase pollen load on the stigma and in fruit production. The present study aimed to identify the pollinator richness of tomato flowers and investigate their morphological and functional traits related to the plant-pollinator interaction in plantations of Central Brazil. The time of anthesis, flower duration, and the number and viability of pollen grains and ovules were recorded. Floral visitors were observed and collected. Flower buds opened around 6h30 and closed around 18h00. They reopened on the following day at the same time in the morning, lasting on average 48 hours. The highest pollen availability occurred during the first hours of anthesis. Afterwards, the number of pollen grains declined, especially between 10h00 to 12h00, which is consistent with the pollinator visitation pattern. Forty bee species were found in the tomato fields, 30 of which were considered pollinators. We found that during the flowering period, plants offered an enormous amount of pollen to their visitors. These may explain the high richness and amount of bees that visit the tomato flowers in the study areas. The period of pollen availability and depletion throughout the day overlapped with the bees foraging period, suggesting that bees are highly effective in removing pollen grains from anthers. Many of these grains probably land on the stigma of the same flower, leading to self-pollination and subsequent fruit development. Native bees (Exomalopsis spp. are effective pollinators of tomato flowers and are likely to contribute to increasing crop productivity. On the other hand, here tomato flowers offer large amounts of pollen resource to a high richness and amount of bees, showing a strong plant-pollinator interaction in the

  7. De Novo Assembly and Transcriptome Analysis of Wheat with Male Sterility Induced by the Chemical Hybridizing Agent SQ-1

    Science.gov (United States)

    Zhang, Gaisheng; Ju, Lan; Zhang, Jiao; Yu, Yongang; Niu, Na; Wang, Junwei; Ma, Shoucai

    2015-01-01

    Wheat (Triticum aestivum L.), one of the world’s most important food crops, is a strictly autogamous (self-pollinating) species with exclusively perfect flowers. Male sterility induced by chemical hybridizing agents has increasingly attracted attention as a tool for hybrid seed production in wheat; however, the molecular mechanisms of male sterility induced by the agent SQ-1 remain poorly understood due to limited whole transcriptome data. Therefore, a comparative analysis of wheat anther transcriptomes for male fertile wheat and SQ-1–induced male sterile wheat was carried out using next-generation sequencing technology. In all, 42,634,123 sequence reads were generated and were assembled into 82,356 high-quality unigenes with an average length of 724 bp. Of these, 1,088 unigenes were significantly differentially expressed in the fertile and sterile wheat anthers, including 643 up-regulated unigenes and 445 down-regulated unigenes. The differentially expressed unigenes with functional annotations were mapped onto 60 pathways using the Kyoto Encyclopedia of Genes and Genomes database. They were mainly involved in coding for the components of ribosomes, photosynthesis, respiration, purine and pyrimidine metabolism, amino acid metabolism, glutathione metabolism, RNA transport and signal transduction, reactive oxygen species metabolism, mRNA surveillance pathways, protein processing in the endoplasmic reticulum, protein export, and ubiquitin-mediated proteolysis. This study is the first to provide a systematic overview comparing wheat anther transcriptomes of male fertile wheat with those of SQ-1–induced male sterile wheat and is a valuable source of data for future research in SQ-1–induced wheat male sterility. PMID:25898130

  8. Genetic architecture of male floral traits required for hybrid wheat breeding.

    Science.gov (United States)

    Boeven, Philipp H G; Longin, C Friedrich H; Leiser, Willmar L; Kollers, Sonja; Ebmeyer, Erhard; Würschum, Tobias

    2016-12-01

    This study revealed a complex genetic architecture of male floral traits in wheat, and Rht-D1 was identified as the only major QTL. Genome-wide prediction approaches but also phenotypic recurrent selection appear promising to increase outcrossing ability required for hybrid wheat seed production. Hybrid wheat breeding is a promising approach to increase grain yield and yield stability. However, the identification of lines with favorable male floral characteristics required for hybrid seed production currently poses a severe bottleneck for hybrid wheat breeding. This study therefore aimed to unravel the genetic architecture of floral traits and to assess the potential of genomic approaches to accelerate their improvement. To this end, we employed a panel of 209 diverse winter wheat lines assessed for male floral traits and genotyped with genome-wide markers as well as for Rht-B1 and Rht-D1. We found the highest proportion of explained genotypic variance for the Rht-D1 locus (11-24 %), for which the dwarfing allele Rht-D1b had a negative effect on anther extrusion, visual anther extrusion and pollen mass. The genome-wide scan detected only few QTL with small or medium effects, indicating a complex genetic architecture. Consequently, marker-assisted selection yielded only moderate prediction abilities (0.44-0.63), mainly relying on Rht-D1. Genomic selection based on weighted ridge-regression best linear unbiased prediction achieved higher prediction abilities of up to 0.70 for anther extrusion. In conclusion, recurrent phenotypic selection appears most cost-effective for the initial improvement of floral traits in wheat, while genome-wide prediction approaches may be worthwhile when complete marker profiles are already available in a hybrid wheat breeding program.

  9. Morphology of floral papillae in Maxillaria Ruiz & Pav. (Orchidaceae).

    Science.gov (United States)

    Davies, K L; Turner, M P

    2004-01-01

    The labellar papillae and trichomes of Maxillaria Ruiz & Pav. show great diversity. Although papillae also occur upon other parts of the flower (e.g. column and anther cap), these have not yet been studied. Labellar trichomes of Maxillaria are useful in taxonomy, but hitherto the taxonomic value of floral papillae has not been assessed. The aim of this paper is to describe the range of floral papillae found in Maxillaria and to determine whether papillae are useful as taxonomic characters. Light microscopy, histochemistry, low-vacuum scanning and transmission electron microscopy. A total of 75 taxa were studied. Conical papillae with rounded or pointed tips were the most common. The column and anther cap usually bear conical, obpyriform or villiform papillae, whereas those around the stigmatic surface and at the base of the anther are often larger and swollen. Labellar papillae show greater diversity, and may be conical, obpyriform, villiform, fusiform or clavate. Papillae may also occur on multiseriate trichomes that perhaps function as pseudostamens. Labellar papillae contain protein but most lack lipid. The occurrence of starch, however, is more variable. Many papillae contain pigment or act as osmophores, thereby attracting insects. Rewards such as nectar or a protein-rich, wax-like, lipoidal substance may be secreted by papillae onto the labellar surface. Some papillae may have a protective role in preventing desiccation. Species of diverse vegetative morphology may have identical floral papillae, whereas others of similar vegetative morphology may not. Generally, floral papillae in Maxillaria have little taxonomic value. Nevertheless, the absence of papillae from members of the M. cucullata alliance, the occurrence of clavate papillae with distended apices in the M. rufescens alliance and the presence of papillose trichomes in some species may yet prove to be useful.

  10. Water status and associated processes mark critical stages in pollen development and functioning

    Science.gov (United States)

    Firon, Nurit; Nepi, Massimo; Pacini, Ettore

    2012-01-01

    Background The male gametophyte developmental programme can be divided into five phases which differ in relation to the environment and pollen hydration state: (1) pollen develops inside the anther immersed in locular fluid, which conveys substances from the mother plant – the microsporogenesis phase; (2) locular fluid disappears by reabsorption and/or evaporation before the anther opens and the maturing pollen grains undergo dehydration – the dehydration phase; (3) the anther opens and pollen may be dispersed immediately, or be held by, for example, pollenkitt (as occurs in almost all entomophilous species) for later dispersion – the presentation phase; (4) pollen is dispersed by different agents, remaining exposed to the environment for different periods – the dispersal phase; and (5) pollen lands on a stigma and, in the case of a compatible stigma and suitable conditions, undergoes rehydration and starts germination – the pollen–stigma interaction phase. Scope This review highlights the issue of pollen water status and indicates the various mechanisms used by pollen grains during their five developmental phases to adjust to changes in water content and maintain internal stability. Conclusions Pollen water status is co-ordinated through structural, physiological and molecular mechanisms. The structural components participating in regulation of the pollen water level, during both dehydration and rehydration, include the exine (the outer wall of the pollen grain) and the vacuole. Recent data suggest the involvement of water channels in pollen water transport and the existence of several molecular mechanisms for pollen osmoregulation and to protect cellular components (proteins and membranes) under water stress. It is suggested that pollen grains will use these mechanisms, which have a developmental role, to cope with environmental stress conditions. PMID:22523424

  11. Obtaining a new variety of rape by biotechnology

    International Nuclear Information System (INIS)

    Chen, Z.H.; Cun, S.X.; Zhang, Z.Z.; Wang, W.F.; Zhang, T.H.; Li, W.B.; Zhang, L.H.

    1990-01-01

    Full text: High-frequency induction of pollen embryoids and plantlets of rape was obtained by stepped float anther culture. In addition, somatic embryoids and plantlets were induced with a high frequency from several species by cell suspension culture. The erucic acid (EA) content of embryoids was analysed by a micro-analysis technique and a semi-micro-analysis of glucosinolates (GS) content in culture was used. A new variety 'H86-166' with low EA and low GS content was selected by these techniques. It gave a yield of 3169 kg/ha and has been released for commercial production on about 1000 ha in Yunnan Province. (author)

  12. Pflanzliche Zellkulturtechniken als Züchtungsschritt am Beispiel Raps

    Science.gov (United States)

    Hoffmann, Franz

    1980-06-01

    A supplementation of classical plant breeding is now necessary due to the limitations imposed by available genetic variability and the slowness of the method. Therefore, cell culture techniques could play an important role in the future. Using rape seed, in which plants derived from anther culture and in vitro mutagenesis are already field tested, it has been shown that, in this case, somatic genetics is very close to becoming a practical method. For most of the other crop plants, in particular the cereals, no such unconventional breeding techniques have yet been satisfactorily established for commercial use.

  13. Calcium in pollen-pistil interaction in `Petunia hybrida Hor`. Pt. 1. Localization of Ca{sup 2+} ions in mature pollen grain using pyroantimonate and autoradiographic methods

    Energy Technology Data Exchange (ETDEWEB)

    Bednarska, E.; Butowt, R. [Uniwersytet Mikolaja Kopernika, Torun (Poland)

    1994-12-31

    The localization of Ca{sup 2+} in the mature pollen grain and the flow of these ions the somatic tissues of the anther to the pollen grains has been studied using pyroantimonate and autoradiographic methods. In the pollen grain, Ca{sup 2+} ions have been localized in the sporoderm in the cytoplasmic vesicles of probably dictyosomal origin. Calcium ions were transported into the sporoderm together with the compounds of degenerating tapetum. The material of degenerating tapetum forms pollen coat surrounding the mature pollen grains. (author). 18 refs, 9 figs.

  14. The X Chromosome Is Necessary for Somatic Development in the Dioecious Silene latifolia: Cytogenetic and Molecular Evidence and Sequencing of a Haploid Genome

    Czech Academy of Sciences Publication Activity Database

    Soukupová, Magda; Nevrtalová, Eva; Čížková, Jana; Vogel, Ivan; Čegan, Radim; Hobza, Roman; Vyskot, Boris

    2014-01-01

    Roč. 143, 1-3 (2014), s. 96-103 ISSN 1424-8581 R&D Projects: GA ČR(CZ) GBP501/12/G090; GA ČR(CZ) GAP501/12/2220; GA ČR(CZ) GAP501/10/0102; GA MŠk(CZ) LM2010005; GA MŠk LO1204 Institutional support: RVO:68081707 Keywords : Anther culture * Cytometry * Dihaploids Subject RIV: BO - Biophysics; EF - Botanics (UEB-Q) Impact factor: 1.561, year: 2014

  15. Post-translational mechanisms are associated with fertility restoration of cytoplasmic male sterility in sugar beet (Beta vulgaris).

    Science.gov (United States)

    Kitazaki, Kazuyoshi; Arakawa, Takumi; Matsunaga, Muneyuki; Yui-Kurino, Rika; Matsuhira, Hiroaki; Mikami, Tetsuo; Kubo, Tomohiko

    2015-07-01

    Genetic conflict between cytoplasmically inherited elements and nuclear genes arising from their different transmission patterns can be seen in cytoplasmic male sterility (CMS), the mitochondrion-encoded inability to shed functional pollen. CMS is associated with a mitochondrial open reading frame (ORF) that is absent from non-sterility inducing mitochondria (S-orf). Nuclear genes that suppress CMS are called restorer-of-fertility (Rf) genes. Post-transcriptional and translational repression of S-orf mediates the molecular action of Rf that encodes a class of RNA-binding proteins with pentatricopeptide repeat (PPR) motifs. Besides the PPR-type of Rfs, there are also non-PPR Rfs, but the molecular interactions between non-PPR Rf and S-orf have not been described. In this study, we investigated the interaction of bvORF20, a non-PPR Rf from sugar beet (Beta vulgaris), with preSatp6, the S-orf from sugar beet. Anthers expressing bvORF20 contained a protein that interacted with preSATP6 protein. Analysis of anthers and transgenic calli expressing a FLAG-tagged bvORF20 suggested the binding of preSATP6 to bvORF20. To see the effect of bvORF20 on preSATP6, which exists as a 250-kDa protein complex in CMS plants, signal bands of preSATP6 in bvORF20-expressing and non-expressing anthers were compared by immunoblotting combined with Blue Native polyacrylamide gel electrophoresis. The signal intensity of the 250-kDa band decreased significantly, and 200- and 150-kDa bands appeared in bvORF20-expressing anthers. Transgenic callus expressing bvORF20 also generated the 200- and 150-kDa bands. The 200-kDa complex is likely to include both preSATP6 and bvORF20. Post-translational interaction between preSATP6 and bvORF20 appears to alter the higher order structure of preSATP6 that may lead to fertility restoration in sugar beet. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  16. Activation analysis of a few flowers of Liliiflorae plants

    International Nuclear Information System (INIS)

    Kawashima, Tatsuro

    1983-01-01

    The flowers of Liliiflorae plants (Lycoris radiata Herb., Lilium longiflorum Thunb. and Crinum asiaticum L.) were divided into leaf, peduncle, bract, perianth, filament, anther, ovary, style, stigma etc. and the distribution of elements in each part was determined. The analytical results revealed that (1) almost all elements were distributed with different concentration according to a part of the flowers, (2) abnormal distribution of cobalt and nickel to genital organ was noticed in Lilium longiflorum Thunb., and (3) high content of cadmium to genital organ and low content of calcium in each part were observed on Crinum asiaticum L. (author)

  17. Mechanical damage in cotton buds caused by the boll weevil

    Directory of Open Access Journals (Sweden)

    Santos Roseane Cavalcanti

    2003-01-01

    Full Text Available The boll weevil (Anthonomus grandis Boheman causes high levels of bud abscission in cotton plants due to feeding or oviposition punctures. It has been reported that abscission is mainly due to enzymes present in the insect's saliva, but mechanical damage could also contribute to square abscission. The objective of this paper was to undertake an analysis of the morphological damages caused by the insect in cotton squares using microscopy. Anthers and ovules are the main target of boll weevil feeding. The process initiates by perforation of young sepal and petal tissues and proceeds with subsequent alimentation on stamen and ovary leading to abscission of floral structures.

  18. Genotypic differences in proembryoid development and green plantlets regeneration through androgenesis in barley varieties Diferenças genotípicas no desenvolvimento de pró-embrióides e regeneração de plântulas verdes via androgênese em genótipo de cevada

    Directory of Open Access Journals (Sweden)

    Paula Wiethölter

    2008-02-01

    Full Text Available The development of in vitro haploid plants followed by spontaneous or induced genome duplication allows to achieve, in one generation, the recovery of total homozygosis. The efficiency of the haplodiploidization process through in vitro anther culture of barley is variable among genotypes. This study was aimed at determining the androgenetic response of nine barley genotypes from the breeding program of Embrapa Trigo, analysing proembryoid development and green plantlets regeneration in anthers cultivated in vitro. Cultivar 'BR2' presented the highest average of proembryoids (104/anther and 'MN698' presented the highest average of green plantlets (0,41/anther. There was a significant variation among the average values of barley genotypes for embryo formation and green plantlets regeneration, making possible the selection to combine androgenetic capacity and good agronomic traits.A obtenção, na cevada, de plantas haplóides in vitro e a posterior duplicação natural ou artificial do genoma permitem alcançar a homozigose completa, em uma geração. A eficiência da haplodiploidização pela cultura de anteras é variável entre os genótipos. Foi avaliada a resposta androgenética através da formação de pró-embrióides e da regeneração de plântulas verdes em nove cultivares do programa de melhoramento de cevada da Embrapa Trigo, em anteras cultivadas in vitro. A cultivar "BR2" apresentou maior média de pró-embrióides (104/antera, enquanto "MN698" mostrou a maior média de plântulas verdes (0,41/antera. Houve variação significativa entre os valores médios dos genótipos em relação à formação de pró-embrióides e à regeneração de plântulas verdes, indicando a possibilidade de seleção para combinar a capacidade androgenética com boas características agronômicas.

  19. Floral biology and reproductive mechanisms of the Ocimum canum Sims (Lamiaceae

    Directory of Open Access Journals (Sweden)

    Cláudio Lúcio Fernandes Amaral

    2008-06-01

    Full Text Available The Ocimum genus (Lamiaceae presents essential oils used in the pharmaceutical, perfume, cosmetics and culinary industries. The aim of this paper was to study the fl oral biology and breeding mechanisms of Ocimum canum Sims. in relation to improved plant breeding. Ocimum canum has inflorescences with white, protandrous and hermaphoditic flowers. The osmophores are located at the anthers and stigma. Anthesis occurs between 10:30 and 11:30 a.m. The main fl oral visitors were bees of the Apis and Augochloropsis genuses. Ocimum canum presents a breeding system with a predominance of outcrossing that possibly demonstrates the wide reproductive flexibility of this species.

  20. Moth pollination of Metaplexis japonica (Apocynaceae): pollinaria transfer on the tip of the proboscis.

    Science.gov (United States)

    Sugiura, Shinji; Yamazaki, Kazuo

    2005-08-01

    Asclepiad pollinaria (including pollen masses) attach to diverse body parts of flower visitors in many ways. In this paper, we observed nocturnal moths (Lepidoptera: Pyralidae and Noctuidae) transporting the pollinaria of the Japanese species Metaplexis japonica (Thunb.) Makino (Apocynaceae: Asclepiadoideae) on the tip of the proboscis. Flowers of this species may induce nectar-feeding moths to pull out the proboscis along a guide rail (anther slit), thus clipping the pollinaria onto the tip of the proboscis and transferring the pollinaria to the next flower. The transfer of pollinaria on the unique vector of a moth proboscis tip is an interesting pollination mechanism among previously reported entomophiles.

  1. Transcriptional regulation of male-sterility in 7B-1 male-sterile tomato mutant

    Czech Academy of Sciences Publication Activity Database

    Omidvar, Vahid; Mohorianu, I.; Dalmay, T.; Zheng, Y.; Fei, Z.; Pucci, A.; Mazzucato, E.; Večeřová, R.; Sedlářová, M.; Fellner, Martin

    2017-01-01

    Roč. 12, č. 2 (2017), č. článku e0170715. E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : tapetum-degeneration-retardation * male reproductive development * early anther development * differential expression * lycopersicon-esculentum * stamenless-2 mutant * abscisic-acid * arabidopsis-thaliana * brassica-napus * cell-wall Subject RIV: EB - Gene tics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 2.806, year: 2016

  2. Two new species of Erica (Ericaceae; one from Western Cape and one from KwaZulu-Natal, South Africa

    Directory of Open Access Journals (Sweden)

    E. G. H. Oliver

    2004-09-01

    Full Text Available Two new species of Erica L. from South Africa are described. E. jananthus E.G.H.Oliv. & I.M .Oliv. is confined to a single peak in the eastern Groot Swartberg Range in Western Cape and usually forms a small, gnarled, woody, shrublet growing in rock crevices with sticky white flowers and black subexserted anthers that have obtrullate decurrent appendages.E. psittacina E.G.H.Oliv. & I.M.Oliv. is from KwaZulu-Natal. It forms large woodv shrubs with numerous bright pinkflowers and occurs as a single population on a mountain near Creighton. Both descriptions are accompanied by line drawings and distribution maps

  3. Potentialités androgénétiques du palmier dattier Phoenix dactylifera L. et culture in vitro d'anthères

    Directory of Open Access Journals (Sweden)

    Harzallah H.

    2002-01-01

    Full Text Available Genetic potentialities if five male date palm genotypes, and in vitro culture of anthers. The experimental results derived from the study of five date palm (Phoenix dactylifera L. genotypes indicate that the ability of microspores to divide varies with genotype and culture medium. The highest frequency of microspore division is obtained with the induction medium [Murashige and Skoog (MS 1962 mineral elements, 2,4-dichlorophenoxyacetique (2,4-D, 2-isopentenylaminopurine (2-IP] containing activated charcoal. The pollinator T106 was considered as the most efficient genotype in our experimentation

  4. WsMAGO2, a duplicated MAGO NASHI protein with fertility attributes interacts with MPF2-like MADS-box proteins.

    Science.gov (United States)

    Ihsan, Humera; Khan, Muhammad Ramzan; Ajmal, Wajya; Ali, Ghulam Muhammad

    2015-05-01

    WsMAGO2 a duplicated protein in Withania through interactions with MPF2-like proteins affects male fertility by producing fewer flowers and aborted non-viable pollens/seeds regulated by anther-specific GAATTTGTGA motif. The MAGO NASHIs are highly conserved genes that encode proteins known to be involved in RNA physiology and many other developmental processes including germ cell differentiation in animals. However, their structural and functional implications in plants as fertility function proteins remained fragmented. MAGO (shorter name of MAGO NASHI) proteins form heterodimers with MPF2-like MADS-box proteins which are recruited in calyx identity and male fertility in Solanaceous plants. Four MAGO genes namely WsMAGO1 and WsMAGO2 and TaMAGO1 and TaMAGO2 were isolated from Withania somnifera and Tubocapsicum anomalum, respectively. These genes have duplicated probably due to whole genome duplication event. Dysfunction of WsMAGO2 through double-stranded RNAi in Withania revealed suppression of RNA transcripts, non-viable pollens, fewer flowers and aborted non-viable seeds in the developing berry suggesting a role of this protein in many traits particularly male fertility. WsMAGO2 flaunted stronger yeast 2-hybrid interactions with MPF2-like proteins WSA206, WSB206 and TAB201 than other MAGO counterparts. The native transcripts of WsMAGO2 culminated in stamens and seed-bearing berries though other MAGO orthologs also exhibited expression albeit at lower level. Coding sequences of the two orthologs are highly conserved, but they differ substantially in their upstream promoter regions. Remarkably, WsMAGO2 promoter is enriched with many anther-specific cis-motifs common in fertility function genes promoters. Among them, disruption of GAATTTGTGA abolished YFP/GUS gene expression in anthers alluding towards its involvement in regulating expression of MAGO in anther. Our findings support a possible recruitment of WsMAGO2 in fertility trait in Withania. These genes have

  5. Plant breeding by using radiation mutation - Selection of herbicide-resistant cell lines by using {gamma}-rays

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyo Yeon [Sunchun University, Sunchun (Korea); Seo, Yong Weon [Korea University, Seoul (Korea)

    2000-04-01

    In order to develop the herbicide resistant cell lines, micro calli derived from rice anther culture and mature seed of wheat cultivars were irradiated with gamma rays. 1) The callus was dedifferentiated by 7 or 21 day pretreatment at 7 deg. C in two rice cultivars, Ilpumbyeo ad Dongjinbyeo. 2) To check the optimum concentration of herbicide, three herbicides were tested with micro calli. 3) The optimum dose of gamma ray to seeds of wheat seemed to be from 100 to 150 Gy. 4) AFLP and RAPD technique were established to develope herbicide resistant molecular marker in rice. 34 refs., 10 figs., 5 tabs. (Author)

  6. Biphasic regulation of the transcription factor ABORTED MICROSPORES (AMS) is essential for tapetum and pollen development in Arabidopsis.

    Science.gov (United States)

    Ferguson, Alison C; Pearce, Simon; Band, Leah R; Yang, Caiyun; Ferjentsikova, Ivana; King, John; Yuan, Zheng; Zhang, Dabing; Wilson, Zoe A

    2017-01-01

    Viable pollen is essential for plant reproduction and crop yield. Its production requires coordinated expression at specific stages during anther development, involving early meiosis-associated events and late pollen wall formation. The ABORTED MICROSPORES (AMS) transcription factor is a master regulator of sporopollenin biosynthesis, secretion and pollen wall formation in Arabidopsis. Here we show that it has complex regulation and additional essential roles earlier in pollen formation. An inducible-AMS reporter was created for functional rescue, protein expression pattern analysis, and to distinguish between direct and indirect targets. Mathematical modelling was used to create regulatory networks based on wild-type RNA and protein expression. Dual activity of AMS was defined by biphasic protein expression in anther tapetal cells, with an initial peak around pollen meiosis and then later during pollen wall development. Direct AMS-regulated targets exhibit temporal regulation, indicating that additional factors are associated with their regulation. We demonstrate that AMS biphasic expression is essential for pollen development, and defines distinct functional activities during early and late pollen development. Mathematical modelling suggests that AMS may competitively form a protein complex with other tapetum-expressed transcription factors, and that biphasic regulation is due to repression of upstream regulators and promotion of AMS protein degradation. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  7. Towards male sterility in Pinus radiata--a stilbene synthase approach to genetically engineer nuclear male sterility.

    Science.gov (United States)

    Höfig, Kai P; Möller, Ralf; Donaldson, Lloyd; Putterill, Joanna; Walter, Christian

    2006-05-01

    A male cone-specific promoter from Pinus radiata D. Don (radiata pine) was used to express a stilbene synthase gene (STS) in anthers of transgenic Nicotiana tabacum plants, resulting in complete male sterility in 70% of transformed plants. Three plants were 98%-99.9% male sterile, as evidenced by pollen germination. To identify the stage at which transgenic pollen first developed abnormally, tobacco anthers from six different developmental stages were assayed microscopically. Following the release of pollen grains from tetrads, transgenic pollen displayed an increasingly flake-like structure, which gradually rounded up during the maturation process. We further investigated whether STS expression may have resulted in an impaired flavonol or sporopollenin formation. A specific flavonol aglycone stain was used to demonstrate that significant amounts of these substances were produced only in late stages of normal pollen development, therefore excluding a diminished flavonol aglycone production as a reason for pollen ablation. A detailed analysis of the exine layer by transmission electron microscopy revealed minor structural changes in the exine layer of ablated pollen, and pyrolysis-gas chromatography-mass spectroscopy indicated that the biochemistry of sporopollenin production was unaffected. The promoter-STS construct may be useful for the ablation of pollen formation in coniferous gymnosperms and male sterility may potentially be viewed as a prerequisite for the commercial use of transgenic conifers.

  8. The petunia ortholog of Arabidopsis SUPERMAN plays a distinct role in floral organ morphogenesis.

    Science.gov (United States)

    Nakagawa, Hitoshi; Ferrario, Silvia; Angenent, Gerco C; Kobayashi, Akira; Takatsuji, Hiroshi

    2004-04-01

    Arabidopsis (Arabidopsis thaliana) SUPERMAN (SUP) plays a role in establishing a boundary between whorls 3 and 4 of flowers and in ovule development. We characterized a Petunia hybrida (petunia) homolog of SUP, designated PhSUP1, to compare with SUP. Genomic DNA of the PhSUP1 partially restored the stamen number and ovule development phenotypes of the Arabidopsis sup mutant. Two P. hybrida lines of transposon (dTph1) insertion mutants of PhSUP1 exhibited increased stamen number at the cost of normal carpel development, and ovule development was defective owing to aberrant growth of the integument. Unlike Arabidopsis sup mutants, phsup1 mutants also showed extra tissues connecting stamens, a petal tube and an ovary, and aberrancies in the development of anther and placenta. PhSUP1 transcripts occurred in the basal region of wild-type flowers around developing organ primordia in whorls 2 and 3 as well as in the funiculus of the ovule, concave regions of the placenta, and interthecal regions of developing anthers. Overexpression of PhSUP1 in P. hybrida resulted in size reduction of petals, leaves, and inflorescence stems. The shortening of inflorescence stems and petal tubes was primarily attributable to suppression of cell elongation, whereas a decrease in cell number was mainly responsible for the size reduction of petal limbs.

  9. Tightly Controlled Expression of bHLH142 Is Essential for Timely Tapetal Programmed Cell Death and Pollen Development in Rice

    Directory of Open Access Journals (Sweden)

    Swee-Suak Ko

    2017-07-01

    Full Text Available Male sterility is important for hybrid seed production. Pollen development is regulated by a complex network. We previously showed that knockout of bHLH142 in rice (Oryza sativa causes pollen sterility by interrupting tapetal programmed cell death (PCD and bHLH142 coordinates with TDR to modulate the expression of EAT1. In this study, we demonstrated that overexpression of bHLH142 (OE142 under the control of the ubiquitin promoter also leads to male sterility in rice by triggering the premature onset of PCD. Protein of bHLH142 was found to accumulate specifically in the OE142 anthers. Overexpression of bHLH142 induced early expression of several key regulatory transcription factors in pollen development. In particular, the upregulation of EAT1 at the early stage of pollen development promoted premature PCD in the OE142 anthers, while its downregulation at the late stage impaired pollen development by suppressing genes involved in pollen wall biosynthesis, ROS scavenging and PCD. Collectively, these events led to male sterility in OE142. Analyses of related mutants further revealed the hierarchy of the pollen development regulatory gene network. Thus, the findings of this study advance our understanding of the central role played by bHLH142 in the regulatory network leading to pollen development in rice and how overexpression of its expression affects pollen development. Exploitation of this novel functionality of bHLH142 may confer a big advantage to hybrid seed production.

  10. BnaA.bZIP1 Negatively Regulates a Novel Small Peptide Gene, BnaC.SP6, Involved in Pollen Activity

    Directory of Open Access Journals (Sweden)

    Xuanpeng Wang

    2017-12-01

    Full Text Available Small peptides secreted to the extracellular matrix control many aspects of the plant’s physiological activities which were identified in Arabidopsis thaliana, called ATSPs. Here, we isolated and characterized the small peptide gene Bna.SP6 from Brassica napus. The BnaC.SP6 promoter was cloned and identified. Promoter deletion analysis suggested that the -447 to -375 and -210 to -135 regions are crucial for the silique septum and pollen expression of BnaC.SP6, respectively. Furthermore, the minimal promoter region of p158 (-210 to -52 was sufficient for driving gene expression specifically in pollen and highly conserved in Brassica species. In addition, BnaA.bZIP1 was predominantly expressed in anthers where BnaC.SP6 was also expressed, and was localized to the nuclei. BnaA.bZIP1 possessed transcriptional activation activity in yeast and protoplast system. It could specifically bind to the C-box in p158 in vitro, and negatively regulate p158 activity in vivo. BnaA.bZIP1 functions as a transcriptional repressor of BnaC.SP6 in pollen activity. These results provide novel insight into the transcriptional regulation of BnaC.SP6 in pollen activity and the pollen/anther-specific promoter regions of BnaC.SP6 may have their potential agricultural application for new male sterility line generation.

  11. Cold-Induced Male Meiotic Restitution in Arabidopsis thaliana Is Not Mediated by GA-DELLA Signaling

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    Bing Liu

    2018-02-01

    Full Text Available Short periods of cold stress induce male meiotic restitution and diploid pollen formation in Arabidopsis thaliana by specifically interfering with male meiotic cytokinesis. Similar alterations in male meiotic cell division and gametophytic ploidy stability occur when gibberellic acid (GA signaling is perturbed in developing anthers. In this study, we found that exogenous application of GA primarily induces second division restitution (SDR-type pollen in Arabidopsis, similar to what cold does. Driven by the close similarity in cellular defects, we tested the hypothesis that cold-induced meiotic restitution is mediated by GA-DELLA signaling. Using a combination of chemical, genetic and cytological approaches, however, we found that both exogenously and endogenously altered GA signaling do not affect the cold sensitivity of male meiotic cytokinesis. Moreover, in vivo localization study using a GFP-tagged version of RGA protein revealed that cold does not affect the expression pattern and abundance of DELLA in Arabidopsis anthers at tetrad stage. Expression study found that transcript of RGA appears enhanced in cold-stressed young flower buds. Since our previous work demonstrated that loss of function of DELLA causes irregular male meiotic cytokinesis, we here conclude that cold-induced meiotic restitution is not mediated by DELLA-dependent GA signaling.

  12. High-spatial and high-mass resolution imaging of surface metabolites of Arabidopsis thaliana by laser desorption-ionization mass spectrometry using colloidal silver.

    Science.gov (United States)

    Jun, Ji Hyun; Song, Zhihong; Liu, Zhenjiu; Nikolau, Basil J; Yeung, Edward S; Lee, Young Jin

    2010-04-15

    High-spatial resolution and high-mass resolution techniques are developed and adopted for the mass spectrometric imaging of epicuticular lipids on the surface of Arabidopsis thaliana. Single cell level spatial resolution of approximately 12 mum was achieved by reducing the laser beam size by using an optical fiber with 25 mum core diameter in a vacuum matrix-assisted laser desorption ionization-linear ion trap (vMALDI-LTQ) mass spectrometer and improved matrix application using an oscillating capillary nebulizer. Fine chemical images of a whole flower were visualized in this high spatial resolution showing substructure of an anther and single pollen grains at the stigma and anthers. The LTQ-Orbitrap with a MALDI ion source was adopted to achieve MS imaging in high mass resolution. Specifically, isobaric silver ion adducts of C29 alkane (m/z 515.3741) and C28 aldehyde (m/z 515.3377), indistinguishable in low-resolution LTQ, can now be clearly distinguished and their chemical images could be separately constructed. In the application to roots, the high spatial resolution allowed molecular MS imaging of secondary roots and the high mass resolution allowed direct identification of lipid metabolites on root surfaces.

  13. Flowering, pollen characteristics and insect foraging on Campanula bononiensis (Campanulaceae, a protected species in Poland

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    Bożena Denisow

    2014-07-01

    Full Text Available This study investigated the floral biology and pollen quantity and quality of Campanula bononiensis L. (Campanulaceae, a protected species in Poland. Observations and measurements were made during the years 2007–2009 in natural phytocoenoses from the Festuco-Brometea class situated within the Lublin area, SE Poland. A considerable decrease (approx. 87% in population density was observed. Significant variations both in the amount of pollen (18.5%–34.8% of pollen in the total anther dry weight, i.e. 0.5–1.5 mg per 10 anthers and in pollen viability (38.8–97.0% were noted. Both a low amount of pollen and low pollen viability may reduce the reproductive success of individuals. The most frequent visiting insects were bees (Apoidea, including solitary bees 45.7%, honeybees 20.4%, and bumblebees 11.4%. Dipterans, coleopterans (weevils, lepidopterans and ants were also recorded, implying a strong impact of C. bononiensis on insect biodiversity within grasslands.

  14. Horse chestnut pollen quality

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    Ćalić Dušica

    2017-01-01

    Full Text Available Pollen quality of horse chestnut, expressed as pollen productivity, viability and germination was studied. Anthers of horse chestnut genotypes had pollen production from 3.66 to 5.06 x 103 pollen grains per anther, depending of genotype. Also, pollen of horse chestnut Ah1-Ah4 genotypes showed different viability (from 56 to 68%, after staining with fluorescein diacetate. Pollen germination of Ah1-Ah4 genotypes varied from 50-66% on basic medium. Inclusion of polyethylene glycol-PEG from 10%, 15% and 20% v/w increased pollen germination. The best results were achieved on medium with the largest PEG concentration. On these medium 76-91% pollen grains were germinated, depending of genotype. The best pollen quality, for all tested parameters, had genotype Ah2. Knowledge about morphology, production, viability, in vitro germination, tube growth as well as pollen: ovule ratio can be of great importance for future pollen biology studies. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 173015

  15. Genetically conditioned male sterility

    International Nuclear Information System (INIS)

    Gottschalk, W.

    1976-01-01

    A survey is given of two different types of genetically controlled male sterility in higher plants. 'Functional' male sterility is due to the action of mutated genes causing a misdifferentiation of the growing points in different specific ways. Under the influence of the genes of this group either the stamens or the archespore tissues are not differentiated. In other mutants functionable male germ cells are produced but cannot be used for fertilizing the egg cells because the anthers remain closed or anthers and stigma become spatially separated from each other. Other genes of the group are responsible for the transformation of stamens into carpels, i.e. for a change of the hermaphrodite flower into a unisexually female one. A second type of male sterility is due to the action of ms genes influencing the course of micro-sporogenesis directly. They cause the breakdown of this process in a specific meiotic stage characteristic for each gene of the group. This breakdown is introduced by the degeneration of PMCs, microspores, or pollen grains preventing the production of male germ cells. The female sex organs remain uninfluenced. (author)

  16. High-Spatial and High-Mass Resolution Imaging of Surface Metabolites of Arabidopsis thaliana by Laser Desorption-Ionization Mass Spectrometry Using Colloidal Silver

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Ji Hyun; Song, Zhihong; Liu, Zhenjiu; Nikolau, Basil J.; Yeung, Edward S.; and Lee, Young Jin

    2010-03-17

    High-spatial resolution and high-mass resolution techniques are developed and adopted for the mass spectrometric imaging of epicuticular lipids on the surface of Arabidopsis thaliana. Single cell level spatial resolution of {approx}12 {micro}m was achieved by reducing the laser beam size by using an optical fiber with 25 {micro}m core diameter in a vacuum matrix-assisted laser desorption ionization-linear ion trap (vMALDI-LTQ) mass spectrometer and improved matrix application using an oscillating capillary nebulizer. Fine chemical images of a whole flower were visualized in this high spatial resolution showing substructure of an anther and single pollen grains at the stigma and anthers. The LTQ-Orbitrap with a MALDI ion source was adopted to achieve MS imaging in high mass resolution. Specifically, isobaric silver ion adducts of C29 alkane (m/z 515.3741) and C28 aldehyde (m/z 515.3377), indistinguishable in low-resolution LTQ, can now be clearly distinguished and their chemical images could be separately constructed. In the application to roots, the high spatial resolution allowed molecular MS imaging of secondary roots and the high mass resolution allowed direct identification of lipid metabolites on root surfaces.

  17. Floral ratios in the figs of Ficus montana span the range from actively to passively pollinated fig trees

    Science.gov (United States)

    Suleman, Nazia; Quinnell, Rupert J.; Compton, Stephen G.

    2014-05-01

    Fig trees (Ficus spp., Moraceae) and their associated obligate pollinator fig wasps (Agaonidae) are partners in what is often a pair-wise species-specific association. Their interaction centres on the unique enclosed inflorescence of Ficus species - the fig. Among dioecious fig tree species, only pollinated ovules in figs on female trees develop into seeds. On male trees, galled ovules support development of the fig wasp offspring that will transport their pollen, but no seeds develop. Some fig wasp species actively collect and disperse pollen, whereas others are typical insect pollinators in that pollen is transferred passively. Active pollination is associated with improved larval survivorship in pollinated figs. Because active pollination is much more efficient, their host figs need to contain far fewer male flowers and across numerous Ficus species anther-ovule ratios are a good predictor of pollination mode. We examined variation in inflorescence size and floral ratios among male figs of the Asian Ficus montana and its consequences for the amounts of pollen that would be available for each pollinator to collect. Inflorescence size (total flower number) was highly variable, and female pollinator offspring production was higher in figs with more female flowers. Pollinator offspring numbers and anther-ovule ratios were also highly variable, and encompassed the range typical of both actively and passively pollinated fig tree species. In combination, this variation resulted in large differences in the extent to which pollinators were competing for access to pollen, with potential fitness consequences for both partners in the mutualism.

  18. Embryology of Siparunaceae (Laurales): characteristics and character evolution.

    Science.gov (United States)

    Kimoto, Yukitoshi; Tobe, Hiroshi

    2003-08-01

    Embryological characters of Siparunaceae, which are poorly understood, were studied on the basis of two constituent genera, an African Glossocalyx and a South American Siparuna, to better understand their evolution within Laurales. These two genera have many embryological characteristics in common with the other lauralean families. Noticeably, they share the multi-celled ovule archesporium (uncertain in Glossocalyx) as a synapomorphy with all the other lauralean families except Lauraceae, the anthers dehisced by valves as a synspomorphy with all the other lauralean families except Calycanthaceae and Monimiaceae, and the bisporangiate anther as a synapomorphy with Gomortegaceae and Atherospermataceae. Siparunaceae are, however, distinct from all other laularean families in having unitegmic ovules that were derived from bitegmic ovules, probably due to an elimination of the outer integument. Likewise, the lack of the testa (i.e., developed outer integument), the "endotegmic" seed coat, and the perichalazal seed at maturity are also characteristics of Siparunaceae. Within the family, Siparuna differs from Glossocalyx in having plural tetrads of megaspores and plural, starchy-rich, one-nucleate, tubular embryo sacs (autapomorphies). On the other hand, Glossocalyx is characterized by having bilaterally flattened seeds (autapomorphy). Although functional aspects of those autapomorphies are uncertain, both Glossocalyx and Siparuna show evolution in different embryological characters.

  19. HISTORY OF in vitro CULTURE STUDIES ON Helianthus annuus L. IN TURKEY

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    Sergun DAYAN

    2016-12-01

    Full Text Available Tissue culture techniques offer important approaches about sunflower breeding and germplasm conservation. The available data on the subject in Turkey was reviewed in order to encourage the researchers to study on tissue culture of sunflower. In vitro studies on sunflower in Turkey started in the first half of the 90s. A large number of in vitro culture studies on sunflower using anthers, hypocotyls, cotyledons, petioles of cotyledon, shoot-tips, mature embryos, immature embryos, leaves, petioles, immature cotyledons and microspores as different explants have been published. Microspore culture, anther culture, embryo culture, slow growth storage, micropropagation and gene transfer with Agrobacterium were also used in these culture studies. Although these studies formed an important scientific knowledge about sunflower tissue culture in the country, it is still not sufficient. Therefore, there is an urgent need to make more in vitro studies on sunflower which is an important agricultural plant for Turkey. The transfer of the results of these studies to agricultural applications is also essential from a sectoral standpoint.

  20. Analysis of a Partial Male-Sterile Mutant of Arabidopsis thaliana Isolated from a Low-Energy Argon Ion Beam Mutagenized Pool

    International Nuclear Information System (INIS)

    Xu Min; Bian Po; Wu Yuejin; Yu Zengliang

    2008-01-01

    A screen for Arabidopsis fertility mutants, mutagenized by low-energy argon ion beam, yielded two partial male-sterile mutants tc243-1 and tc243-2 which have similar phenotypes. tc243-2 was investigated in detail. The segregation ratio of the mutant phenotypes in the M2 pools suggested that mutation behaved as single Mendelian recessive mutations. tc243 showed a series of mutant phenotypes, among which partial male-sterile was its striking mutant characteristic. Phenotype analysis indicates that there are four factors leading to male sterility. a. Floral organs normally develop inside the closed bud, but the anther filaments do not elongate sufficiently to position the locules above the stigma at anthesis. b. The anther locules do not dehisce at the time of flower opening (although limited dehiscence occurs later). c. Pollens of mutant plants develop into several types of pollens at the trinucleated stage, as determined by staining with DAPI (4',6-diamidino-2-phenylindole), which shows a variable size, shape and number of nucleus. d. The viability of pollens is lower than that of the wild type on the germination test in vivo and vitro.

  1. Comparative studies of mitochondrial proteomics reveal an intimate protein network of male sterility in wheat (Triticum aestivum L.)

    Science.gov (United States)

    Wang, Shuping; Zhang, Gaisheng; Zhang, Yingxin; Song, Qilu; Chen, Zheng; Wang, Junsheng; Guo, Jialin; Niu, Na; Wang, Junwei; Ma, Shoucai

    2015-01-01

    Plant male sterility has often been associated with mitochondrial dysfunction; however, the mechanism in wheat (Triticum aestivum L.) has not been elucidated. This study set out to probe the mechanism of physiological male sterility (PHYMS) induced by the chemical hybridizing agent (CHA)-SQ-1, and cytoplasmic male sterility (CMS) of wheat at the proteomic level. A total of 71 differentially expressed mitochondrial proteins were found to be involved in pollen abortion and further identified by MALDI-TOF/TOF MS (matrix-assisted laser desorption/ionization-time of fight/time of flight mass spectrometry). These proteins were implicated in different cellular responses and metabolic processes, with obvious functional tendencies toward the tricarboxylic acid cycle, the mitochondrial electron transport chain, protein synthesis and degradation, oxidation stress, the cell division cycle, and epigenetics. Interactions between identified proteins were demonstrated by bioinformatics analysis, enabling a more complete insight into biological pathways involved in anther abortion and pollen defects. Accordingly, a mitochondria-mediated male sterility protein network in wheat is proposed; this network was further confirmed by physiological data, RT-PCR (real-time PCR), and TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling) assay. The results provide intriguing insights into the metabolic pathway of anther abortion induced by CHA-SQ-1 and also give useful clues to identify the crucial proteins of PHYMS and CMS in wheat. PMID:26136264

  2. The biological effect of gamma radiation on in vitro culture in rice

    International Nuclear Information System (INIS)

    Wang Cailian; Xu Gang; Shen Mei; Chen Qiufang

    1994-08-01

    Radiobiological effects of gamma radiation on different types of rice before or during in vitro culture, combined treatments of 137 Cs γ-rays and NaN 3 on mature embryo culture, and irradiation on growth of calli derived from anther in rice were studied. The dose-effects relations of callus induction rate and callus growth rate could be fitted according to the multi-target and single-hit model. Effect of somatic cultures of different types in rice was different. Increase in plant regeneration capacity was found with 100, 150 Gy gamma rays. Decrease of callus induction rate, callus growth rate and callus differentiation rate (especially in the 1st culture) were observed in combined treatments of γ-rays and NaN 3 . However, mutagenic effects of treatments with γ-rays were much higher than those of combined treatment of γ-rays and NaN 3 in the 2nd and the 3rd culture. Combined treatments of 137 Cs γ-rays with 200 Gy and 2 mmol NaN 3 were suitable for explant in rice before culture. To irradiate the calli derived from anther in rice with 30 Gy gamma rays can rise plant regeneration capacity during continuing culture

  3. Molecular phenotypes associated with anomalous stamen development in Alternanthera philoxeroides

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    Zhu eZhu

    2015-04-01

    Full Text Available Alternanthera philoxeroides is a perennial amphibious weed native to South America but has now spread to diverse parts of the world. A. philoxeroides reproduces both sexually and asexually in its native range, but propagates solely through vegetative means in its introduced range. Traits associated with sexual reproduction become degraded for sexual dysfunction, with flowers possessing either pistillate stamens or male-sterile anthers. Degradations of sexual characters for loss of sexuality commonly take place in clonal plants. The underlying molecular-genetic processes remain largely unknown. We compared the gene expression profiles of abnormal stamens with that of normal stamens by RNA-Seq analysis, and identified a large number of differentially expressed genes between abnormal and normal stamens. In accordance with flower morphology, the expression of B-class MADS-box genes (ApAP3, ApTM6 and ApPI was markedly reduced in pistillate stamens. However, most of the genes involved in meiosis were expressed normally in stamens with male-sterile anthers. In addition to verifying the expression patterns of genes previously known to be related to stamen and pollen grain development, we also identified previously unknown molecular phenotypes associated with sexual dysfunction in A. philoxeroides, that is helpful for dissecting the molecular mechanisms underpinning various male-sterile phenotypes and the molecular processes underlying the transition from sexuality to asexuality in clonal plants.

  4. Androgenesis in Solanaceae.

    Science.gov (United States)

    Seguí-Simarro, Jose M

    2016-01-01

    The Solanaceae is one of the most important families for global agriculture. Among the different solanaceous species, tobacco (Nicotiana tabacum), potato (Solanum tuberosum), tomato (Solanum lycopersicum), eggplant (Solanum melongena), and pepper (Capsicum annuum) are five crops of outstanding importance worldwide. In these crops, maximum yields are produced by hybrid plants created by crossing pure (homozygous) lines with the desired traits. Pure lines may be produced by conventional breeding methods, which is time consuming and costly. Alternatively, it is possible to accelerate the production of pure lines by creating doubled haploid (DH) plants derived from (haploid) male gametophytes or their precursors (androgenesis). In this way, the different steps for the production of pure lines can be reduced to only one generation, which implies important time and cost savings. This and other advantages make androgenic DHs the choice in a number of important crops where any of the different experimental in vitro techniques (anther culture or isolated microspore culture) is well set up. The Solanaceae family is an excellent example of heterogeneity in terms of response to these techniques, including highly responding species such as tobacco, considered a model system, and tomato, one of the most recalcitrant species, where no reliable and reproducible methods are yet available. Interestingly, the first evidence of androgenesis, particularly through in vitro anther culture, was demonstrated in a solanaceous species, Datura innoxia. In this chapter, we report the state of the art of the research about androgenic DHs in Solanaceae, paying special attention to datura, tobacco, potato, tomato, eggplant, and pepper.

  5. THE INFLUENCE OF SOWING TERM ON THE DURUM WHEAT INDUCTION ABILITY IN SOUTH UKRAINE

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    I. S. Zambriborsh

    2014-08-01

    Full Text Available The sowing term of spring durum wheat influence on the induction ability in the South Ukraine was evaluated. Wheat was sowed in two terms: April, 11 and April, 18 of 2013. Two sowing term were different in the growing conditions. The second term is characterized with higher temperature and lower soil humidity during wheat germination and growing. Wheat spikes were cut in appropriate microspore development stage according to standard protocol. Anthers were cultivated on different cultural media. We used standard protocols as well as our own improved protocols of media preparation. The level of sowing term and plant culture media on the induction ability of different wheat genotypes was estimated. Stress growing conditions increased the induction ability of durum wheat. The new formation percentage was higher for the second sowing term wheat on different media. However it was shown that the level of sowing term influence was lower on appropriate cultural media. Key words: in vitro anther culture, durum wheat, sowing term, new formation induction.

  6. Androecia in two Clusia species: development, structure and resin secretion.

    Science.gov (United States)

    Sá-Haiad, B; Silva, C P; Paula, R C V; Rocha, J F; Machado, S R

    2015-07-01

    Clusia fluminensis and C. lanceolata are dioecious shrubs having resiniferous flowers with strongly distinct androecia. The aim of this study was to investigate the development and anatomy of their androecia and the ultrastructure, histochemistry and secretory process of their androecium resin glands, examining whether the cellular aspects of resin secretion differed between these two morphologically distinct androecia. Stamens differ, being free in C. fluminensis and clustered in a synandrium in C. lanceolata. Staminode sterility is due to the undifferentiated nature of the anthers in C. lanceolata and degeneration of meiocytes and anther indehiscence in C. fluminensis. Resin is produced in subepidermal cavities and canals with wide lumens. In the secretory stage, epithelial cells present sinuous walls, voluminous nuclei, polymorphic plastids associated with periplastidial reticulum, mitochondria, oil bodies, multivesicular bodies, endoplasmic reticulum and dictyosomes. The resin is released through rupture points on the distal surface of stamens and staminodes, associated with disrupted cavities and canals. Our results show morphological diversity associated with functional similarity. Also, a secretion pattern shared by the two species includes initiation of the secretory process in young floral buds, compartmentalisation of the secretion in pre-anthesis buds and release of secretions at anthesis. Cellular aspects of resin secretion in these species are quite similar, as are the chemical identities of the main components of the floral resins of the genus. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  7. Potential pollinators of Comolia ovalifolia DC Triana (Melastomataceae and Chamaecrista ramosa (Vog. H.S. Irwin and Barneby var. ramosa (Leguminosae-Caesalpinioideae, in restinga, Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    P. Oliveira-Rebouças

    Full Text Available Comolia ovalifolia DC Triana (Melastomataceae and Chamaecrista ramosa (Vog. H.S. Irwin and Barneby var. ramosa (Leguminosae - Caesalpinioideae are tropical plant species found in restinga (herbaceous-shrubby, sandy costal ecosystems. They have flowers with poricidal anthers and are pollinated by bees. The study sought to analyse potential pollinators of both plants during visits to their flowers in a restinga area in Bahia. The flowering displayed by both species was considered continuous and long duration, constantly providing pollen to floral visitors. C. ovalifolia was visited by 17 species of bees and C. ramosa by 16 species, predominantly from the Apidae family (with a similarity index of 74%. The behavior displayed by these visiting bees was of vibrating anthers. The small-sized Euglossa sp. Latreille, 1802 and Florilegus similis Urban, 1970 bees played less of a role as pollinators, since they rarely touched the flower stigma during harvests and were thus considered opportunist visitors or casual pollinators. Centris decolorata Lepetier, 1841 (= C. leprieuri and Xylocopa subcyanea Perez, 1901 are large bees and were considered efficient pollinators of C. ovalifolia and C. ramosa because of the higher frequency and constancy of their visits, and their favourable behaviour and size for pollen transfer between flowers, which guarantees the survival of these native restinga plant species.

  8. Expression Pattern of Class B Gene PAP3 in Flower Development of Pepper

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    Xin Li

    2013-12-01

    Full Text Available Class B gene APETALA3 (AP3 plays a key role in the development of petals and stamens. Here, we investigated the expression pattern of PAP3 gene (genbank accession number: HM104635 in the buds of cytoplasmic male sterility line 121A and its near-isogenic restorer line 121C at four developmental stages and analyzed the possible association between Class B genes and cytoplasmic male sterility of pepper. Semi-quantitative PCR and quantitative real-time RT-PCR (qRT-PCR as well as RNA in situ hybridization showed increased expression of PAP3 at late phase of anther development and its higher expression in restorer line compared with sterility line indicating PAP3’s role at late developmental stage of anther and suppressed expression in sterility line. RNA in situ hybridization showed Class B gene features: high abundance in stamen and petal; lower expression in pistil; no expression in sepal. Results of transient expression in onion epidermal cells also showed PAP3 localized in the nucleus, which is consistent with the expression pattern of transcription factors of MADS-box gene family.

  9. Pewarisan Karakter Kualitatif Cabai Hias Hasil Persilangan Cabai Besar dan Cabai Rawit

    Directory of Open Access Journals (Sweden)

    Siti Hapshoh

    2017-01-01

    Full Text Available ABSTRACTThe fruit of ornamental chili functioned as ornamental as well as for consumption, and therefore it requires diversity of traits for selection process. Information on inheritance pattern of the traits are needed for effective selection. The ideotype of ornamental chili are shortened internode that form a bouquet of flowers, erect fruit orientation and contain anthocyanins for attractive appearance. The research was aimed to study qualitative characters inheritance associated with shortened internode, fruit orientation and anthocyanins content. This study used 6 population including female parent (P1 which has anthocyanin in flower parts, the male parent (P2 bird pepper which has the character of a shortened internode, F1, F1R, BCP1, BCP2, and F2. Data were analyzed with Chi-square test to determine the Mendelian ratio in the F2 population. The results showed that there were characters that was controlled by one gene or two genes. Shortened internode and erect fruit orientation were controlled by a single recessive gene with a ratio of 1:3. On the other hand the color of anthocyanin in the anther stem was controlled by one dominant gene with a ratio of 3:1. The characters controlled by two genes that were dominant and recessive epistasis was the color of anthocyanins in the anther with the ratio 13:3.Keywords: Mendelian ratio, antosianin, shortened internode

  10. Use of intergeneric cross for production of doubled haploid wheat (triticum aestivum l.)

    International Nuclear Information System (INIS)

    Khan, M.A.; Shaukat, S.; Kashif, M.; Khan, A.S.

    2012-01-01

    The main purpose of conventional breeding or hybridisation is to bring about homozygosity, for which 6 to 7 years may be required. Wheat and maize crosses have proved to be more efficient in DH lines production than anther culture methods, because of its lower genetic specificity. Doubled haploid technique facilitates the development of homozygous plants within one generation. The system is developed through haploid production, followed by chromosome doubling, to produce homozygous plants in a single generation. For doubled haploid production method wheat and maize crossing system is better than anther culture and ovule culture because maize pollens are highly responsive and produce stable progeny population. Wheat is being used as female parent and maize as a male parent for the production of doubled haploid. Moreover, Silver Nitrate (AgNO/sub 3/) in tiller culture media can improve the frequency of haploid embryo production in this crossing system. Our result showed that DH production through wheat and maize crossing system was proved to be time saving (2 years) as compared to other conventional breeding methods (6 years). (author)

  11. Ultraviolet-B (UV-B) radiation under high-temperature conditions affects growth of rice (cv. Koshihikari) after a young panicle formation stage

    International Nuclear Information System (INIS)

    Inaba, K.

    2005-01-01

    A japonica rice (cv. Koshihikari) was used to test the effects on blooming and ripening of UV-B radiation treatment combined with high temperature treatments (day/night, 35 / 30 deg C). Strong UV-B radiation (60.4 kJ/m(2) . day) slightly increased sterility. High temperatures and weak UV-B radiation (18.1 kJ/m(2) . day) applied together from two weeks before heading and from the heading day increased sterility and those applied from two weeks after heading decreased sterility. High temperature combined with strong UV-B radiation applied from two weeks before heading increased sterility and decreased the size of unhulled grain and anther length. The same treatment given from the heading stage greatly increased sterility and decreased anther length and pollen production, and that given two weeks after heading decreased unhulled grain weight. It also decreased photosynthetic rate in Flag leaves. A high temperature applied together with strong UV-B radiation had a synergistic effect causing poor growth; it increased the harmful effects of a high temperature and strong UV-B given separately, on the sterility and pollen formation

  12. Changes in gene expression during male meiosis in Petunia hybrida.

    Science.gov (United States)

    Cnudde, Filip; Hedatale, Veena; de Jong, Hans; Pierson, Elisabeth S; Rainey, Daphne Y; Zabeau, Marc; Weterings, Koen; Gerats, Tom; Peters, Janny L

    2006-01-01

    We analyzed changes in gene expression during male meiosis in Petunia by combining the meiotic staging of pollen mother cells from a single anther with cDNA-AFLP transcript profiling of mRNA from the synchronously developing sister anthers. The transcript profiling experiments focused on the identification of genes with a modulated expression profile during meiosis, while premeiotic archesporial cells and postmeiotic microspores served as a reference. About 8000 transcript tags, estimated at 30% of the total transcriptome, were generated, of which around 6% exhibited a modulated gene expression pattern at meiosis. Cluster analysis revealed a transcriptional cascade that coincides with the initiation and progression through all stages of the two meiotic divisions. Fragments that exhibited high expression specifically during meiosis I were characterized further by sequencing; 90 out of the 293 sequenced fragments showed homology with known genes, belonging to a wide range of gene classes, including previously characterized meiotic genes. In-situ hybridization experiments were performed to determine the spatial expression pattern for five selected transcript tags. Its concurrence with cDNA-AFLP transcript profiles indicates that this is an excellent approach to study genes involved in specialized processes such as meiosis. Our data set provides the potential to unravel unique meiotic genes that are as yet elusive to reverse genetics approaches.

  13. Diversity and evolution of floral structure among early diverging lineages in the Ericales.

    Science.gov (United States)

    Schönenberger, Jürg; von Balthazar, Maria; Sytsma, Kenneth J

    2010-02-12

    This is a combination of review and original data on floral structure and diversity in the two earliest diverging lineages of the Ericales, i.e. the balsaminoids, comprising Balsaminaceae, Marcgraviaceae and Tetrameristaceae, and the polemonioids, comprising Fouquieriaceae and Polemoniaceae. Each clade is strongly supported in molecular studies, while structural synapomorphies have largely been lacking. For the balsaminoid families, we compare floral morphology, anatomy and histology among selected taxa and find that the entire clade is strongly supported by the shared presence of nectariferous tissue in the floral periphery, thread-like structures on anthers, truncate stigmas, secretion in the ovary, as well as mucilage cells, raphides and tannins in floral tissues. A possible sister group relationship between Balsaminaceae and Tetrameristaceae is supported by the shared presence of post-genital fusion of filaments and ovary and a star-shaped stylar canal. For polemonioids, we document unexpected diversity of floral features in Polemoniaceae, partly providing structural links to Fouquieriaceae. Features include cochlear and quincuncial corolla aestivation, connective protrusions, ventrifixed anthers and nectariferous tissue in the base of the ovary. In addition, we outline future directions for research on floral structure in the Ericales and briefly discuss the general importance of structural studies for our understanding of plant phylogeny and evolution.

  14. POLA REPRODUKSI PADA SALAK BALI (SA/ACCA ZA/ACCA VAR. AMBOINENSIS (BECC. MOGEA

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    ENIEK KRISWIYANTI

    2008-12-01

    Full Text Available Research on reproduction patterns of Balinese snake skin fruits (Salak Bali has been conducted by identifying the availability of pollens on anthers of male and hermaphrodite flowers, the viability of pollens in the pistillum and the present of embryo(s in the ovulum. Flower samples were collected from Sibetan and Muncan Villages, Karangasem regency. Sample preparations and identifications were conducted in "Stuktur dan Perkembangan Tumbuhan Laboratory" Department of Bilogy, FMIPA Udayana University. The results showed that the pollen has a single apperture, unisulcus, minuta, oblat sferoidal type. The length of polar axis was 15-24 jam (P and equatorial diameter of 16-24 |im (E. Therefore, the P/E index was 0.99-1.0. The pollen viability before and after anthesis of hermaphrodite flowers was low (71.4% and 50.6% respectively, with very low pollen tube germinations (0.08% of before and 0.48% after anthesis. Similarly, on the anthers of male flowers, the viability of pollens before anthesis was low (75.7% with pollen germination of 0.18%, and event lower in after anthesis flowers (28.8% with 0.29% pollen tube germination. Squashed stigma before and after anthesis and 2 days after flowers were opened showed that there was no germination occurred. Therefore, there was no germination in the pistillum, but the embryo developed before flower anthesis, indicates that the reproduction pattern of Salak Bali occurred without fertilizations (agamospermy.

  15. Stage-Specific Gene Profiling of Germinal Cells Helps Delineate the Mitosis/Meiosis Transition.

    Science.gov (United States)

    Yuan, Ting-Lu; Huang, Wei-Jie; He, Juan; Zhang, Dong; Tang, Wei-Hua

    2018-02-01

    In flowering plants, germ lines are induced from somatic meristems within reproductive organs. Within anthers, germinal cell initials first undergo several rounds of mitotic proliferation before synchronously entering meiosis. Our understanding of the progression and the molecular basis of this mitosis to meiosis transition is still limited. Taking advantage of the correlation between anther length and premeiotic germinal cell development in maize ( Zea mays ), we studied the transcriptome dynamics of germinal cells at three sequential stages, mitotic archesporial cells, enlarging pollen mother cells at the premeiosis interphase, and pollen mother cells at the early prophase of meiosis, using laser microdissection-based expression profiling. Our analysis showed that cells undergoing the mitosis-meiosis switch exhibit robust transcriptional changes. The three stages are distinguished by the expression of genes encoding transcription factor subsets, meiotic chromosome recombination proteins, and distinct E3 ubiquitin ligases, respectively. The transcription level of genes encoding protein turnover machinery was significantly higher in these three stages of germinal cells than in mature pollen, parenchyma cells, or seedlings. Our experimental results further indicate that many meiotic genes are not only transcribed, but also translated prior to meiosis. We suggest that the enlarging pollen mother cells stage represents a crucial turning point from mitosis to meiosis for developing germinal cells. © 2018 American Society of Plant Biologists. All Rights Reserved.

  16. Stage-Specific Gene Profiling of Germinal Cells Helps Delineate the Mitosis/Meiosis Transition1[OPEN

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    He, Juan; Zhang, Dong

    2018-01-01

    In flowering plants, germ lines are induced from somatic meristems within reproductive organs. Within anthers, germinal cell initials first undergo several rounds of mitotic proliferation before synchronously entering meiosis. Our understanding of the progression and the molecular basis of this mitosis to meiosis transition is still limited. Taking advantage of the correlation between anther length and premeiotic germinal cell development in maize (Zea mays), we studied the transcriptome dynamics of germinal cells at three sequential stages, mitotic archesporial cells, enlarging pollen mother cells at the premeiosis interphase, and pollen mother cells at the early prophase of meiosis, using laser microdissection-based expression profiling. Our analysis showed that cells undergoing the mitosis-meiosis switch exhibit robust transcriptional changes. The three stages are distinguished by the expression of genes encoding transcription factor subsets, meiotic chromosome recombination proteins, and distinct E3 ubiquitin ligases, respectively. The transcription level of genes encoding protein turnover machinery was significantly higher in these three stages of germinal cells than in mature pollen, parenchyma cells, or seedlings. Our experimental results further indicate that many meiotic genes are not only transcribed, but also translated prior to meiosis. We suggest that the enlarging pollen mother cells stage represents a crucial turning point from mitosis to meiosis for developing germinal cells. PMID:29187566

  17. Apis mellifera (Hymenoptera: Apidae) as a potential Brassica napus pollinator (cv. Hyola 432) (Brassicaceae), in Southern Brazil.

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    Rosa, A S; Blochtein, B; Ferreira, N R; Witter, S

    2010-11-01

    Brassica napus Linnaeus is considered a self-compatible crop; however, studies show that bee foraging elevates their seed production. Considering bee food shortages during the winter season and that the canola is a winter crop, this study aimed to evaluate the foraging behaviour of Apis mellifera Linnaeus, 1758 regarding those flowers, and to verify if it presents adequate behaviour for successfully pollinating this crop in Rio Grande do Sul State. The study was carried out in a canola field, in Southern Brazil. The anthesis stages were morphologically characterised and then related to stigma receptivity and pollen grain viability. Similarly, the behaviour of A. mellifera individuals on flowers was followed, considering the number of flowers visited per plant, the amount of time spent on the flowers, touched structures, and collected resources. Floral fidelity was inferred by analysing the pollen load of bees collected on flowers. The bees visited from 1-7 flowers/plant (x = 2.02; sd = 1.16), the time spent on the flowers varied between 1-43 seconds (x = 3.29; sd = 2.36) and, when seeking nectar and pollen, they invariably touched anthers and stigmas. The pollen load presented 100% of B. napus pollen. The bees' attendance to a small number of flowers/plants, their short permanence on flowers, their contact with anthers and stigma and the integral floral constancy allows their consideration as potential B. napus pollinators.

  18. Biología floral de Passiflora foetida (Passifloraceae

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    María T. Amela García

    1998-06-01

    Full Text Available Un experimento reproductivo muestra que Passiflora foetida es autocompatible. Observaciones de las características florales y de los visitantes durante la antesis, más el análisis del polen transportado, permitieron identificar el síndrome floral (melitofilia y las funciones de cada visitante. La antesis ocurre desde las 6 hasta las 11 hs. Se identificaron 3 fases florales: 1 estigmas por encima de las anteras, 2 estigmas a la altura de las anteras, 3 estigmas por encima de las anteras; los radii, los pétalos y los sépalos se incurvan. Los estigmas están receptivos durante toda la antesis. La concentración de azúcares del néctar es 34 %. El color predominante en el espectro visible es el blanco. En el espectro UV, los estambres y el gineceo contrastan con el limen y el androginóforo; pueden ser una guía de néctar. Tres especies de himenópteros fueron los visitantes más frecuentes y constantes: Ptiloglossa tarsata (Colletidae siempre contactan las anteras y los estigmas cuando liban, transportan un alto porcentaje de polen de P. foetida y visitan flores en fase 1 y 2; pueden ser considerados los principales polinizadores. Pseudaugochloropsis sp. (Halictidae raramente contactan las anteras o los estigmas cuando perforan el limen para acceder al néctar y visitan flores en fase 2 y 3; son ladrones de néctar que raramente polinizan. Augochlorella sp. (Halictidae recolectan polen sin tocar los estigmas y visitan flores en fase 2 y 3; son hurtadores de polen.A reproductive experiment shows that Passiflora foetida is autocompatible. Observations of floral characteristics and visitors during anthesis, plus the analysis of pollen allowed identification of floral syndrome (melittophily and functions for each visitor. Anthesis occurs from 6 to 11 AM. Three floral phases were identified: 1 stigmas above anthers, 2 stigmas at anther level, 3 stigmas above anthers; radii, petals and sepals become incurved. The stigmas are receptive during the

  19. Floral reward in Ranunculaceae species

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    Bożena Denisow

    2016-04-01

    Full Text Available Floral reward is important in ecological and evolutionary perspectives and essential in pollination biology. For example, floral traits, nectar and pollen features are essential for understanding the functional ecology, the dynamics of pollen transport, competition for pollinator services, and patterns of specialization and generalization in plant–pollinator interactions. We believe to present a synthetic description in the field of floral reward in Ranunculaceae family important in pollination biology and indicating connections between ecological and evolutionary approaches. The links between insect visitors’ behaviour and floral reward type and characteristics exist. Ranunculaceae is a family of aboot 1700 species (aboot 60 genera, distributed worldwide, however the most abundant representatives are in temperate and cool regions of the northern and southern hemispheres. The flowers are usually radially symmetric (zygomorphic and bisexual, but in Aconitum, Aquilegia are bilaterally symmetric (zygomorphic. Most Ranunculaceae flowers offer no nectar, only pollen (e.g., Ranunculus, Adonis vernalis, Thalictrum, but numerous species create trophic niches for different wild pollinators (e.g. Osmia, Megachile, Bombus, Andrena (Denisow et al. 2008. Pollen is a source of protein, vitamins, mineral salts, organic acids and hormones, but the nutritional value varies greatly between different plant species. The pollen production can differ significantly between Ranunculacea species. The mass of pollen produced in anthers differ due to variations in the number of developed anthers. For example, interspecies differences are considerable, 49 anthers are noted in Aquilegia vulgaris, 70 anthers in Ranunculus lanuginosus, 120 in Adonis vernalis. A significant intra-species differences’ in the number of anthers are also noted (e.g. 41 to 61 in Aquilegia vulgaris, 23-45 in Ranunculus cassubicus. Pollen production can be up to 62 kg per ha for Ranunculus acer

  20. Ultrastructural calli analysis of Inga vera Willd. subsp. Affinis (DC. T.D. Penn Análise ultraestrutural de calos de ingazeiro (Inga vera Willd. subsp. Affinis (DC. T.D. Penn.

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    Vanessa Cristina Stein

    2010-10-01

    Full Text Available Subcellular changes are relevant to understand plant organogenesis and embryogenesis in the early stages of cell development. The cytology during cell development in tissue culture is however still poorly characterized. This study aimed to characterize the ultrastructural differences related to callogenesis of anthers, ovaries, leaf and nodal segments of Inga vera Willd. subsp. Affinis (DC. T.D. Penn. Flower buds, nodal segments and leaves were disinfected and inoculated in test tubes containing MS medium with 3% sucrose and 4.5µM 2.4-D, except for leaf callogenesis, where 9µM of this auxin was used, and for the callogenesis of anthers and ovaries, where the culture medium was enriched with 0.25% activated charcoal and 90µM PVP. After 45 days in culture medium, the anther, ovary, leaf and nodal segment calli were fixed in Karnovisky and prepared for visualization by scanning and transmission electron microscopy. Ultrastructural differences were observed among the callus cells of anthers, ovaries, segments and leaves. There was no evidence of somatic embryo formation in the anther, leaf and nodal segment calli, in spite of some embryogenic characteristics in the cells. The ovary calli, with indications of embryo formation, seem to be the most responsive explant source for embryogenesis.A compreensão da organogênese e embriogênese de plantas, nos estágios iniciais de desenvolvimento das células, requer a observação das mudanças subcelulares. No entanto, a caracterização citológica durante o desenvolvimento desses estágios não tem sido realizada com frequência na cultura de tecidos. Portanto, o objetivo deste trabalho foi caracterizar as diferenças ultraestruturais relacionadas a calogênese de anteras, ovários, folha e segmentos nodais de Inga vera Willd. subsp. Affinis (DC. T.D. Penn. Para tanto, botões florais, segmentos nodais e folhas foram desinfestados e inoculados em tubos de ensaio contendo meio MS com 3% de sacarose e

  1. Reproductive biology of Pittosporum dasycaulon Miq., (Family Pittosporaceae) a rare medicinal tree endemic to Western Ghats.

    Science.gov (United States)

    Gopalakrishnan, Krishna Kumar; Thomas, Thuruthiyil Dennis

    2014-12-01

    For successful cultivation and conservation of plants a detailed knowledge of their reproductive biology is required. The reproductive features of trees are important to determine the diversity patterns and community structure of tropical forests. The present study on reproductive biology of Pittosporum dasycaulon, a rare medicinal tree, was conducted in the shola forests of Vaghamon hills, one of the foot hills of Southern Western Ghats of India from 2008-2011. The plant flowers profusely during February to April. Inflorescence is a raceme and the total number of flowers per inflorescence varies from 96-217. The flowers are comparatively small, hermaphrodite, short pedicellate, complete, zygomorphic, pentamerous, polypetalous, hypogynous and light cream in colour with an average length of 1.14 cm. Anthesis started at 08.30 h and the flowers were completely opened at approximately 09.30 h followed by anther deshiscence at 10.00-11.30 h. The pollen grains were trizonocolpate with 45 ± 5.6 μm in size. Acetocarmine staining showed 66 ± 6% fertile pollen at the time of anther dehiscence. The number of pollen grains in an anther is 5246 ± 845 and per flower is 26230 ± 1021. The stigma is wet, non-papillate, capitate and contains a thin film of exudates under the light microscope. The superior ovary is densely covered with papillate hairs and containing 3-8 ovules. The important floral visitors include bees and butterflies. The plant is self-incompatible and an out crosser. Fruit set under open-pollination was poor (24%) with 58.3% fruits having seeds inside. There was no fruit set in manually self pollinated flowers while over 57% of the cross pollinated flowers set fruits. Our study presents a detailed account on reproductive biology of this medicinal tree which may help in the conservation and genetic improvement of this particular taxa.

  2. [Effects of exogenous silicon on the pollination and fertility characteristics of hybrid rice under heat stress during anthesis].

    Science.gov (United States)

    Wu, Chen-Yang; Chen, Dan; Luo, Hai-Wei; Yao, Yi-min; Wang, Zhi-Wei; Tsutomu, Matsui; Tian, Xiao-Hai

    2013-11-01

    Taking two medium-maturing indica rice hybrids Jinyou 63 and Shanyou 63 as test materials, this paper studied the effects of applying silicon fertilizer on the flag leaf chlorophyll content, photosynthetic properties, antioxidant enzyme activities, malondialdehyde (MDA) content, pollen vigor, anther acid invertase activity, pollination, and seed-setting of hybrid rice under the heat stress during anthesis. This study was conducted in pots and under growth chamber. Soluble solution of silicon fertilizer applied as Na2SiO3 x 9H2O was sprayed on the growing plants after early jointing stage, with three times successively and at an interval of one week. The pots were then moved into growth chamber to subject to normal temperature vs. high temperature (termed as heat stress) for five days. In treatment normal temperature, the average daily temperature was set at 26.6 degrees C, and the maximum daily temperature was set at 29.4 degres C; in treatment high temperature, the average and the maximum daily temperature were set at 33.2 degrees C and 40.1 degrees C, respectively. As compared with the control, applying silicon increased the flag leaf chlorophyll content significantly, improved the net photosynthetic rate and stomatal conductance, decreased the accumulative inter- cellular CO2 concentration, improved the leaf photosynthesis, reduced the MDA content, and improved the activities of SOD, POD and CAT under heat stress. In addition, applying silicon improved the anther acid invertase activity and the pollen vigor, increased the anther basal dehiscence width, total number of pollination per stigma, germinated number, germination rate of pollen, and percentage of florets with more than 10 germinated pollen grains, decreased the percentage of florets with fewer than 20 germinated pollen grains, and thus, alleviated the fertility loss of Jinyou 63 and Shanyou 63 under heat stress by 13.4% and 14.1%, respectively. It was suggested that spraying exogenous silicon in the

  3. Biologia floral de uma população de Mirabilis jalapa L. (Nyctaginaceae do Sul do Brasil Floral biology of a population of Mirabilis jalapa L. (Nyctaginaceae from Southern Brazil

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    Yoko Terada

    2001-05-01

    Full Text Available Neste estudo foi investigado o padrão reprodutivo de uma população de Mirabilis jalapa cultivada na Região Sul do território brasileiro. A abertura das flores de M. jalapa ocorreu no início da tarde, às 17 h, e o fechamento foi na manhã seguinte a partir das 4h30min até as 6 h. A abertura das anteras ocorreu a partir das 19h30min até as 20h30min. Foi observada a presença de grãos de pólen na superfície do estigma das flores cujas anteras estavam no mesmo nível, ou num nível superior ao do estigma. A ausência de grãos de pólen no estigma foi verificada nas flores cujas anteras estavam num nível abaixo do da posição do estigma, bem como no estigma de flores previamente emasculadas. Somente uma mariposa foi observada, durante todo o período dos experimentos, visitando e provavelmente polinizando flores de M. jalapa. A autopolinização foi o modo predominante de reprodução na população de M. jalapa cultivada no jardim da Universidade Estadual de MaringáThe reproductive pattern of a cultivated population of Mirabilis jalapa in the Southern region of Brazil was investigated. Flowers of M. jalapa opened for one night, in the early evening at 17h00 and closed early the next morning from 4h30 to 6h00. Anther dehiscence occurred from about 19h30 to 20h30. The presence of pollen grains on the stigma surface was recorded in flowers in which the anther lay at the same level as the stigma or higher. Absence of pollen grains was observed in flowers in which the anther was below the stigma and in previously emasculated flowers. One moth was reported to be the only visitor and possible pollinator of M. jalapa flowers throughout the experimental period. Self-pollination was the predominant mode of reproduction in the M. jalapa population cultured in the garden of the State University of Maringá

  4. Whole-Organ analysis of calcium behaviour in the developing pistil of olive (Olea europaea L. as a tool for the determination of key events in sexual plant reproduction

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    Zienkiewicz Krzysztof

    2011-11-01

    Full Text Available Abstract Background The pistil is a place where multiple interactions between cells of different types, origin, and function occur. Ca2+ is one of the key signal molecules in plants and animals. Despite the numerous studies on Ca2+ signalling during pollen-pistil interactions, which constitute one of the main topics of plant physiology, studies on Ca2+ dynamics in the pistil during flower formation are scarce. The purpose of this study was to analyze the contents and in situ localization of Ca2+ at the whole-organ level in the pistil of olive during the whole course of flower development. Results The obtained results showed significant changes in Ca2+ levels and distribution during olive pistil development. In the flower buds, the lowest levels of detectable Ca2+ were observed. As flower development proceeded, the Ca2+ amount in the pistil successively increased and reached the highest levels just after anther dehiscence. When the anthers and petals fell down a dramatic but not complete drop in calcium contents occurred in all pistil parts. In situ Ca2+ localization showed a gradual accumulation on the stigma, and further expansion toward the style and the ovary after anther dehiscence. At the post-anthesis phase, the Ca2+ signal on the stigmatic surface decreased, but in the ovary a specific accumulation of calcium was observed only in one of the four ovules. Ultrastructural localization confirmed the presence of Ca2+ in the intracellular matrix and in the exudate secreted by stigmatic papillae. Conclusions This is the first report to analyze calcium in the olive pistil during its development. According to our results in situ calcium localization by Fluo-3 AM injection is an effective tool to follow the pistil maturity degree and the spatial organization of calcium-dependent events of sexual reproduction occurring in developing pistil of angiosperms. The progressive increase of the Ca2+ pool during olive pistil development shown by us reflects

  5. Evolvement of transgenic male-sterility and fertility-restoration system in rice for production of hybrid varieties.

    Science.gov (United States)

    Rao, Gundra Sivakrishna; Deveshwar, Priyanka; Sharma, Malini; Kapoor, Sanjay; Rao, Khareedu Venkateswara

    2018-01-01

    We have developed a unique male-sterility and fertility-restoration system in rice by combining Brassica napus cysteine-protease gene (BnCysP1) with anther-specific P12 promoter of rice for facilitating production of hybrid varieties. In diverse crop plants, male-sterility has been exploited as a useful approach for production of hybrid varieties to harness the benefits of hybrid vigour. The promoter region of Os12bglu38 gene of rice has been isolated from the developing panicles and was designated as P12. The promoter was fused with gusA reporter gene and was expressed in Arabidopsis and rice systems. Transgenic plants exhibited GUS activity in tapetal cells and pollen of the developing anthers indicating anther/pollen-specific expression of the promoter. For engineering nuclear male sterility, the coding region of Brassica napus cysteine protease1 (BnCysP1) was isolated from developing seeds and fused to P12 promoter. Transgenic rice plants obtained with P12-BnCysP1 failed to produce functional pollen grains. The F 1 seeds obtained from BnCysP1 male-sterile plants and untransformed controls showed 1:1 (tolerant:sensitive) ratio when germinated on the MS medium supplemented with phosphinothricin (5 mg/l), confirming that the male sterility has been successfully engineered in rice. For male fertility restoration, transgenic rice plants carrying BnCysP1Si silencing system were developed. The pollination of BnCysP1 male-sterile (female-fertile) plants with BnCysP1Si pollen resulted in normal grain filling. The F 1 seeds of BnCysP1 × BnCysP1Si when germinated on the MS basal medium containing PPT (5 mg/l) and hygromycin (70 mg/l) exhibited 1:1 (tolerant:sensitive) ratio and the tolerant plants invariably showed normal grain filling. The overall results clearly suggest that the customized male-sterility & fertility-restoration system can be exploited for quality hybrid seed production in various crops.

  6. MYB transcription factor gene involved in sex determination in Asparagus officinalis.

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    Murase, Kohji; Shigenobu, Shuji; Fujii, Sota; Ueda, Kazuki; Murata, Takanori; Sakamoto, Ai; Wada, Yuko; Yamaguchi, Katsushi; Osakabe, Yuriko; Osakabe, Keishi; Kanno, Akira; Ozaki, Yukio; Takayama, Seiji

    2017-01-01

    Dioecy is a plant mating system in which individuals of a species are either male or female. Although many flowering plants evolved independently from hermaphroditism to dioecy, the molecular mechanism underlying this transition remains largely unknown. Sex determination in the dioecious plant Asparagus officinalis is controlled by X and Y chromosomes; the male and female karyotypes are XY and XX, respectively. Transcriptome analysis of A. officinalis buds showed that a MYB-like gene, Male Specific Expression 1 (MSE1), is specifically expressed in males. MSE1 exhibits tight linkage with the Y chromosome, specific expression in early anther development and loss of function on the X chromosome. Knockout of the MSE1 orthologue in Arabidopsis induces male sterility. Thus, MSE1 acts in sex determination in A. officinalis. © 2016 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

  7. Radiation studies in Lens culinaris: impact of absorbed polonium on microsporogenesis

    International Nuclear Information System (INIS)

    Singh, V.K.; Tauheed, Nusrat; Jha, V.N.; Tripathi, R.M.

    2008-01-01

    The root systems of fully grown plants of Lens culinaris (2n=14) were exposed to solutions of different concentrations of polonium (mixture of 208 Po and 209 Po Energy of alpha being 5.1 MeV and 4.9 MeV respectively). Variability in duration of exposure was also maintained. The controlled samples showed normal behavior of chromosomes forming seven bivalents with varying numbers of chiasmata. However, the pollen grain mother cells (PMC) of treated plants harbored a broad spectrum of chromosomal aberrations viz. Clumped configurations, multivalent formation, sticky anaphase bridge and laggards. Clumped configurations following surface stickiness was the most prominent manifestation. It appeared that the alpha particles emitted by the polonium atoms, logged in different organs including the anthers, created a situation akin to chronic internal radiation and inflicting injuries of different extent on the chromosome surface. (author)

  8. The Pollen Coat Proteome: At the Cutting Edge of Plant Reproduction

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    Juan David Rejón

    2016-01-01

    Full Text Available The tapetum is a single layer of secretory cells which encloses the anther locule and sustains pollen development and maturation. Upon apoptosis, the remnants of the tapetal cells, consisting mostly of lipids and proteins, fill the pits of the sculpted exine to form the bulk of the pollen coat. This extracellular matrix forms an impermeable barrier that protects the male gametophyte from water loss and UV light. It also aids pollen adhesion and hydration and retains small signaling compounds involved in pollen–stigma communication. In this study, we have updated the list of the pollen coat’s protein components and also discussed their functions in the context of sexual reproduction

  9. Aggressive displacement of Xylocopa nigrita carpenter bees from flowers of Lagenaria sphaerica (Cucurbitaceae by territorial male Eastern Olive Sunbirds (Cyanomitra olivacea in Tanzania

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    Jeff Ollerton

    2013-05-01

    Full Text Available Male Eastern Olive Sunbirds (Cyanomitra olivacea and Xylocopa nigrita carpenter bees in Tanzania both utilise the flowers of male plants of Lagenaria sphaerica (Cucurbitaceae as a source of nectar. The sunbirds set up territories defending this nectar resource. Observations of interactions between the sunbirds and the carpenter bees show that the bees are aggressively displaced from flowers when spotted by the birds. Only the bees can be considered as legitimate pollinators as the birds do not contact the anthers of the male flowers and were never seen visiting nectarless female flowers of Lagenaria sphaerica. Such territory defence may have implications for the frequency of movement and composition of pollen being transferred from male to female flowers which warrants further research.

  10. Effects of silicon on seed setting rate of rice intersubspecific hybrids.

    Science.gov (United States)

    Li, W-C; Zhang, L; Wang, J; Wang, D; Wang, T-X; Duan, C-X

    2015-09-01

    The present study found semi-sterility in rice intersubspecific hybrids of 'Taichung 65' x 'Guangluai 4' and 'Ludao' x 'Qiuguang'. Embryo sac fertility was evaluated using the overall staining transparent method. The results showed that the embryo sac contained a normal egg cell, normal synergid cells, polar nuclei cells, and antipodal cells, indicating that semi-sterility was caused mainly by pollen semi-sterility. In the pot experiment, the effects of silicon on the seed-setting rate of the two intersubspecific hybrids were examined. The results showed that the rate of anther dehiscence, number of pollen per stigma of Fl plants, potential of pollen grain germination, and fertility of the spikelet were significantly improved by the utilization of silicon fertilizer.

  11. AtSRP1, SMALL RUBBER PARTICLE PROTEIN HOMOLOG, functions in pollen growth and development in Arabidopsis.

    Science.gov (United States)

    Chi, Yong Hun; Kim, Sun Young; Lee, Eun Seon; Jung, Young Jun; Park, Joung Hun; Paeng, Seol Ki; Oh, Hun Taek; Melencion, Sarah Mae Boyles; Alinapon, Cresilda Vergara; Lee, Sang Yeol

    2016-06-24

    To identify novel roles of SMALL RUBBER PARTICLE PROTEIN Homolog in the non-rubber-producing plant Arabidopsis (AtSRP1), we isolated a T-DNA-insertion knock-out mutant (FLAG_543A05) and investigated its functional characteristics. AtSRP1 is predominantly expressed in reproductive organs and is localized to lipid droplets and ER. Compared to wild-type (WT) Arabidopsis, atsrp1 plants contain small siliques with a reduced number of heterogeneously shaped seeds. The size of anther and pollen grains in atsrp1 is highly irregular, with a lower grain number than WT. Therefore, AtSRP1 plays a novel role related to pollen growth and development in a non-rubber-producing plant. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Micromorphology and ultrastructure of the floral nectaries of Viola odorata L. (Violaceae

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    Natalia Wiśniewska

    2015-05-01

    Full Text Available In Viola odorata two inferior anthers have connective appendages (nectaries projecting into the corolla spur. Nectaries are approx. 4 mm long, elongate, with the top of the nectary bending to the lateral wall of the spur. In the top part and in the abaxial surface of middle part of the nectary all cells have papillae. Nectar is secreted through the modified stomata distributed mainly in the top of nectary The nectary consists of single-layered epidermis, nectary parenchyma and subnectary parenchyma. Features of the nectary parenchyma cells, like dense cytoplasm containing numerous mitochondria and large nuclei, are connected with high metabolic cell activity. The vascularization includes both phloem and xylem. A slight amount of starch in the nectary cells, the profusion of plasmodesmata connecting secretory cells and the presence of vascular bundles suggest that sugars secreted in the nectar were delivered by the phloem sap.

  13. Meriania franciscana (Melastomataceae, una especie nueva de los Andes de Ecuador

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    Ulloa Ulloa, Carmen

    2008-12-01

    Full Text Available Meriania franciscana C. Ulloa & Homeier (Melastomataceae from the southeastern province of Zamora-Chinchipe, Ecuador, is described and illustrated. It is distinguished by the markedly dimorphic stamens, the connective of the antipetalous anthers prominently thickened and with two appendages, one subulate and the other oblongoid, the inflorescence with numerous flowers of c. 15 mm. It is only known form the Andean forests at the San Francisco Biological Reserve.Se describe e ilustra una especie nueva, Meriania franciscana C. Ulloa & Homeier (Melastomataceae de la provincia suroriental de Zamora-Chinchipe, Ecuador. Esta especie se caracteriza por los marcados estambres dimorfos, el conectivo de las anteras de los estambres opositipétalos notoriamente hinchado y con dos apéndices, uno subulado y otro alargado y obtuso, y las inflorescencias con numerosas flores pequeñas de c. 15 mm. Sólo se conoce de los bosques andinos en la Reserva Biológica San Francisco.

  14. Further observations on the activity of Y chromosome heterochromatin in Rumex thyrsiflorus

    Directory of Open Access Journals (Sweden)

    J. Żuk

    2015-01-01

    Full Text Available Observation of premeiotic nuclei of plants containing different numbers (from one to five of Y chromosomes reveal that is such plants prior to meiosis all Y chromosomes are in fuzzy state, while in nuclei of tapetal cells or nuclei from anther stalk the number of big chromocentres is directly correlated with the number of Y chromosomes in given plants. This finding provides a further indication of genetic activity of Y chromosomes in this particular stage of the life cycle (premeiosis. Another indication of genetical activity of Y chromosomes was obtained from analysis of the rate of RNA synthesis in premeiosis. It was found that PMC's in the last premeioitc interphase exhibit a high rate of 3H-uridine incorporation. Thus in PMC's the fuzzy appearance of Y chromosomes coincides with intensive RNA synthesis.

  15. Androgenesis, gynogenesis, and parthenogenesis haploids in cucurbit species.

    Science.gov (United States)

    Dong, Yan-Qi; Zhao, Wei-Xing; Li, Xiao-Hui; Liu, Xi-Cun; Gao, Ning-Ning; Huang, Jin-Hua; Wang, Wen-Ying; Xu, Xiao-Li; Tang, Zhen-Hai

    2016-10-01

    Haploids and doubled haploids are critical components of plant breeding. This review is focused on studies on haploids and double haploids inducted in cucurbits through in vitro pollination with irradiated pollen, unfertilized ovule/ovary culture, and anther/microspore culture during the last 30 years, as well as comprehensive analysis of the main factors of each process and comparison between chromosome doubling and ploidy identification methods, with special focus on the application of double haploids in plant breeding and genetics. This review identifies existing problems affecting the efficiency of androgenesis, gynogenesis, and parthenogenesis in cucurbit species. Donor plant genotypes and surrounding environments, developmental stages of explants, culture media, stress factors, and chromosome doubling and ploidy identification are compared at length and discussed as methodologies and protocols for androgenesis, gynogenesis, and parthenogenesis in haploid and double haploid production technologies.

  16. Ecological features of flowers and the amount of pollen released in Corylus avellana (L. and Alnus glutinosa (L. Gaertn.

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    Krystyna Piotrowska

    2012-12-01

    Full Text Available Hazel and alder bloom as one of the first plants in climatic conditions of Poland. In the present study, detailed observations were made of the structure of flowers of Corylus avellana L. and Alnus glutinosa (L. Gaertn. Pollen yield of the abovementioned species was determined. The number of pollen grains in the theca, anther, flower and inflorescence was calculated. A comparison was made of the number of pollen grains of these taxa recorded during the atmospheric pollen seasons analysed over a period of 8 years in the conditions of Lublin. The study demonstrates that pollen yield of the common hazel inflorescence was 66 mg, whereas for black alder it was 120 mg. It was found that the number of pollen grains produced by the alder inflorescence was 2.2 times higher than by the hazel inflorescence. The atmospheric pollen season of the studied plant taxa was recorded at similar dates, but alder pollen was in much larger concentrations.

  17. Desenvolvimento de populações duplo-haplóides de cevada cervejeira associadas à atividade das enzimas (1-3, 1-4-β-glucanases Development of doubled-haploids populations in malting barley associated to activity of enzymes (1-3, 1-4-β-glucanases

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    Janaína Endres Georg-Kraemer

    2011-05-01

    Full Text Available Populações duplo-haplóides apresentam especial vantagem para análises genéticas, uma vez que a informação que elas oferecem pode ser maximizada, devido ao fato que todos os locos encontram-se em homozigose. O objetivo deste trabalho foi o desenvolvimento de duas populações duplo-haplóides (DHs de cevada (Hordeum vulgare ssp. vulgare L. segregantes para a atividade das enzimas (1-3, 1-4-β-glucanases, através da técnica de cultura de anteras. Foram realizados dois cruzamentos com cultivares contrastantes para esta característica. As cultivares parentais selecionadas foram 'MN 698' e 'CEV 97047', para o desenvolvimento da população "malte verde" (MV, e 'Embrapa 127' e 'CEV 96025' para o desenvolvimento da população "malte seco" (MS. Foram cultivadas 10.734 anteras da população MS e 4.139 anteras da população MV. A população MV produziu 50% mais plântulas verdes quando comparada à população MS, refletindo a importância do genótipo na resposta à cultura de anteras e na regeneração. A maioria das plantas adultas duplo-haplóides foi obtida através da duplicação espontânea in vitro do genoma haplóide, ocorrendo em 66% das plantas da população MS e 76% das plantas da população MV. Também foram observadas, em menor frequência, plantas haplóides, triplóides e tetraplóides. Através da técnica de cultura de anteras, foram desenvolvidas 204 linhagens duplo-haplóides, das quais 72 linhagens são da população "malte seco" e 132 linhagens são da população "malte verde". Este material constitui um importante germoplasma para o melhoramento genético da cevada.Doubled haploid populations offer special advantages in genetic analyses, since the information they provide may be maximized due to the fact that all loci are homozygous. The aim of this study was to develop two barley (Hordeum vulgare ssp.vulgare L. doubled-haploid (DHs populations segregating to (1-3, 1-4-β-glucanases activity, utilizing the anther

  18. Detection of chitinolytic enzymes with different substrate specificity in tissues of intact sundew (Drosera rotundifolia L.): chitinases in sundew tissues.

    Science.gov (United States)

    Libantová, Jana; Kämäräinen, Terttu; Moravcíková, Jana; Matusíková, Ildikó; Salaj, Jan

    2009-05-01

    The round-leaf sundew (Drosera rotundifolia L.) is a carnivorous plant expressing a wide range of chitinolytic enzymes playing role in many different processes. In this study the intact plants were analyzed for the presence of chitinase transcripts and chitinolytic activities in different organs. In situ hybridization with chitnase fragment as a probe has revealed the presence of chitinases in the mesophyll cells of leaves and vascular elements of stems of healthy, non-stressed plants. More pronounced expression was observed in cortex and stele cells of roots as well as in ovules and anthers of reproductive organs. Similarly, higher chitinase enzyme activity was typical for flowers and roots suggesting a more specific role of chitinases in these tissues. In addition to endochitinases of different substrate specificities, chitobiosidases contributed to overall chitinolytic activity of tissue extracts. The activity of chitobiosidases was again typical for flowers and roots, while their role in plant physiology remains to be elucidated.

  19. BIOLOGI REPRODUKSI BUNGA Cassine koordersii Kostermans (Celastraceae KOLEKSI KEBUN RAYA BOGOR

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    D. Ardhianto

    2009-01-01

    Full Text Available A study on flower biology of Cassine koordersii Kostermans was carried out in the Bogor Botanic Garden on April — November 2002. The plant produces flowers in umbel inflorescences that open sequentially, starting from the lowest branch of the inflorescence. There is no spatial separation between the anther and the stigma, and the dispersal of highly viable pollen takes place within the period of stigma receptivity. The flowers also show some characters of entomophily. Visitor insects are flies (ordo Diptera, family Syrphidae and Tachinidae and ants (ordo Hymenoptera, family Formicidae. In general, the morphological and phenological characteristics of the flower allow self pollination to occur successfully. Floral assessment using Cruden's Outcrossing Index showed that the flower is self-compatible.

  20. Single Platform Geolocation of Radio Frequency Emitters

    Science.gov (United States)

    2015-03-26

    that [9] Rxx = QDQH = [ Qs Qw ]  Ds 00 σ2wI  [ Qs Qw ]H (2.26) where Qs consists of the K eigenvectors which span the signal...When K < M the matrix ARssAH is singular with rank K and the relation [19] det ( ARssAH ) = det ( Rxx − σ2wI ) = 0 (2.27) indicates that σ2w is an...There are K linearly independent eigenvectors qs with corresponding eigenvalues λs of the matrix ARssAH which are also eigenvectors of Rxx as shown by [9

  1. THE INFLUENCE OF SOWING TERM ON THE DURUM WHEAT INDUCTION ABILITY IN SOUTH UKRAINE

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    Zambriborsh I. S.

    2014-08-01

    Full Text Available The sowing term of spring durum wheat influence on the induction ability in the South Ukraine was evaluated. Wheat was sowed in two terms: April, 11 and April, 18 of 2013. Two sowing term were different in the growing conditions. The second term is characterized with higher temperature and lower soil humidity during wheat germination and growing. Wheat spikes were cut in appropriate microspore development stage according to standard protocol. Anthers were cultivated on different cultural media. We used standard protocols as well as our own improved protocols of media preparation. The level of sowing term and plant culture media on the induction ability of different wheat genotypes was estimated. Stress growing conditions increased the induction ability of durum wheat. The new formation percentage was higher for the second sowing term wheat on different media. However it was shown that the level of sowing term influence was lower on appropriate cultural media.

  2. A comparison of pollen-siring ability and life history between males and hermaphrodites of subdioecious Silene acaulis

    DEFF Research Database (Denmark)

    Philipp, Marianne; Jakobsen, Ruth Bruus; Nachman, Gøsta Støger

    2009-01-01

    , fruit and seed set, as well as pollen per anther for the individuals used in the experiment, as well as for a large number of other individuals to allow us to make comparisons between the three types of individuals.Conclusions: Well-developed pollen grains from males or hermaphrodites did not differ......, hermaphrodite, and male individuals. The sex expression of males and hermaphrodites can vary over years for the same individual, while females are always females. Previous studies have shown that outcrossed seeds from females become seedlings with higher survival and growth rates than those from outcrossed...... seeds from hermaphrodites.Questions: (1) Do pollen grains from males exhibit some advantage over pollen from (1) Do pollen grains from males exhibit some advantage over pollen from hermaphrodites? In particular, do they sire more seeds than hermaphrodites? (2) Is the reproductive system of S. acaulis...

  3. Autophagy, programmed cell death and reactive oxygen species in sexual reproduction in plants.

    Science.gov (United States)

    Kurusu, Takamitsu; Kuchitsu, Kazuyuki

    2017-05-01

    Autophagy is one of the major cellular processes of recycling of proteins, metabolites and intracellular organelles, and plays crucial roles in the regulation of innate immunity, stress responses and programmed cell death (PCD) in many eukaryotes. It is also essential in development and sexual reproduction in many animals. In plants, although autophagy-deficient mutants of Arabidopsis thaliana show phenotypes in abiotic and biotic stress responses, their life cycle seems normal and thus little had been known until recently about the roles of autophagy in development and reproduction. Rice mutants defective in autophagy show sporophytic male sterility and immature pollens, indicating crucial roles of autophagy during pollen maturation. Enzymatic production of reactive oxygen species (ROS) by respiratory burst oxidase homologues (Rbohs) play multiple roles in regulating anther development, pollen tube elongation and fertilization. Significance of autophagy and ROS in the regulation of PCD of transient cells during plant sexual reproduction is discussed in comparison with animals.

  4. Application of the comet assay in studies of programmed cell death (PCD in plants

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    Maria Charzyńska

    2014-01-01

    Full Text Available Programmed cell death (PCD in plants is an intensively investigated process. One of the main characteristics of PCD in both animal and plant organisms is the non-random, internucleosomal fragmentation of nuclear DNA, usually analysed using total DNA gel electrophoresis or TUNEL method. In this paper we present application of the "comet assay" (Single Cell Gel Electrophoresis for detection of nDNA degradation in studies of PCD during plant life cycle. We analyzed three types of tissue: anther tapetum, endosperm and mesophyll which were prepared in different ways to obtain a suspension of viable cells (without cell walls. The comet assay gives a possibility of examination of the nDNA degradation in individual cell. This method is significant for studies of the plant tissue differentiation and senescence especially in the cases when it is not possible to isolate large number of cells at the same developmental stage.

  5. Overexpression of maize anthocyanin regulatory gene Lc affects rice fertility.

    Science.gov (United States)

    Li, Yuan; Zhang, Tao; Shen, Zhong-Wei; Xu, Yu; Li, Jian-Yue

    2013-01-01

    Seventeen independent transgenic rice plants with the maize anthocyanin regulatory gene Lc under control of the CaMV 35S promoter were obtained and verified by molecular identification. Ten plants showed red spikelets during early development of florets, and the degenerate florets were still red after heading. Additionally, these plants exhibited intense pigmentation on the surface of the anther and the bottom of the ovary. They were unable to properly bloom and were completely sterile. Following pollination with normal pollen, these plants yielded red caryopses but did not mature normally. QRT-PCR analysis indicated that mRNA accumulation of the CHS-like gene encoding a chalcone synthase-related protein was increased significantly in the sterile plant. This is the first report to suggest that upregulation of the CHS gene expression may result in rice sterility and affect the normal development of rice seeds.

  6. Selection of reference genes for quantitative real-time PCR expression studies of microdissected reproductive tissues in apomictic and sexual Boechera

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    Amiteye Samuel

    2011-08-01

    Full Text Available Abstract Background Apomixis, a natural form of asexual seed production in plants, is considered to have great biotechnological potential for agriculture. It has been hypothesised that de-regulation of the sexual developmental pathway could trigger apomictic reproduction. The genus Boechera represents an interesting model system for understanding apomixis, having both sexual and apomictic genotypes at the diploid level. Quantitative qRT-PCR is the most extensively used method for validating genome-wide gene expression analyses, but in order to obtain reliable results, suitable reference genes are necessary. In this work we have evaluated six potential reference genes isolated from a 454 (FLX derived cDNA library of Boechera. RNA from live microdissected ovules and anthers at different developmental stages, as well as vegetative tissues of apomictic and sexual Boechera, were used to validate the candidates. Results Based on homologies with Arabidopsis, six genes were selected from a 454 cDNA library of Boechera: RPS18 (Ribosomal sub protein 18, Efalpha1 (Elongation factor 1 alpha, ACT 2 (Actin2, UBQ (polyubiquitin, PEX4 (Peroxisomal ubiquitin conjugating enzyme and At1g09770.1 (Arabidopsis thaliana cell division cycle 5. Total RNA was extracted from 17 different tissues, qRT-PCRs were performed, and raw Ct values were analyzed for primer efficiencies and gene ratios. The geNorm and normFinder applications were used for selecting the most stable genes among all tissues and specific tissue groups (ovule, anthers and vegetative tissues in both apomictic and sexual plants separately. Our results show that BoechRPS18, BoechEfα1, BoechACT2 and BoechUBQ were the most stable genes. Based on geNorm, the combinations of BoechRPS18 and BoechEfα1 or BoechUBQ and BoechEfα1 were the most stable in the apomictic plant, while BoechRPS18 and BoechACT2 or BoechUBQ and BoechACT2 performed best in the sexual plant. When subgroups of tissue samples were analyzed

  7. Molecular Mapping of D1, D2 and ms5 Revealed Linkage between the Cotyledon Color Locus D2 and the Male-Sterile Locus ms5 in Soybean

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    Alina Ott

    2013-07-01

    Full Text Available In soybean, genic male sterility can be utilized as a tool to develop hybrid seed. Several male-sterile, female-fertile mutants have been identified in soybean. The male-sterile, female-fertile ms5 mutant was selected after fast neutron irradiation. Male-sterility due to ms5 was associated with the “stay-green” cotyledon color mutation. The cotyledon color trait in soybean is controlled by two loci, D1 and D2. Association between cotyledon color and male-sterility can be instrumental in early phenotypic selection of sterility for hybrid seed production. The use of such selection methods saves time, money, and space, as fewer seeds need to be planted and screened for sterility. The objectives of this study were to compare anther development between male-fertile and male-sterile plants, to investigate the possible linkages among the Ms5, D1 and D2 loci, and to determine if any of the d1 or d2 mutations can be applied in hybrid seed production. The cytological analysis during anther development displayed optically clear, disintegrating microspores and enlarged, engorged pollen in the male-sterile, female-fertile ms5ms5 plants, a common characteristic of male-sterile mutants. The D1 locus was mapped to molecular linkage group (MLG D1a and was flanked by Satt408 and BARCSOYSSR_01_1622. The ms5 and D2 loci were mapped to MLG B1 with a genetic distance ~12.8 cM between them. These results suggest that use of the d2 mutant in the selection of male-sterile line may attenuate the cost hybrid seed production in soybean.

  8. It takes two to tango: self incompatibility in the bromeliad Tillandsia streptophylla (Bromeliaceae in Mexico

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    Ivón M Ramírez Morillo

    2009-09-01

    Full Text Available Floral phenology and breeding system of Tillandsia streptophylla (Bromeliaceae were studied in a low inundated forest in Yucatan, Mexico. During the flowering season, from March to August, terminal scapose 1-branched, paniculate inflorescences are produced with one flower per branch opening per day, over a period of 11-29 days. Flowers are tubular, light violet, with the stigma placed below the anthers, both protruding above the corolla. Flowers are protandrous, with anthers releasing pollen from 0500 hours and stigma becoming receptive around 0900 hours. Controlled experimental crosses suggest that Tillandsia streptophylla is self incompatible and therefore, pollinator-dependent. Rev. Biol. Trop. 57 (3: 761-770. Epub 2009 September 30.Estudiamos la fenología floral y el sistema de cruzamiento de la bromelia Tillandsia streptophylla (Bromeliaceae en una selva baja inundable en Yucatán, México. Durante la estación de floración (marzo a agosto, las plantas producen una inflorescencia terminal, escaposa, paniculada, 1-dividida, con una flor abriendo por rama por día para un período de floración de 11-29 días por inflorescencia. Las flores son tubulares, de corola violeta claro, con el estigma y anteras exertos, pero las anteras más largas que el estigma en antesis. Las flores son protandras, con las anteras liberando el polen desde las 0500 horas y la receptividad del estigma comenzando a las 0900 horas. Los cruces experimentales controlados sugieren que Tillansdia streptophylla es auto incompatible y por ende, dependiente de los polinizadores.

  9. GENETIC DIVERGENCE AMONG Passiflora cristalina Vanderpl & Zappi. GENOTYPES BASED ON FLOWER AND FRUIT CHARACTERISTICS

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    GREICIELE FARIAS DA SILVEIRA

    Full Text Available ABSTRACT This study aimed to evaluate the genetic divergence among Passiflora cristalina genotypes and quantify the relative contribution of 30 flower and fruit characteristics, seeking to support the preservation and characterization of genetic resources of the species for preservation and use in future breeding programs. We evaluated 150 fruit and 150 flowers collected in 15 genotypes with naturally occurring in the municipality of Alta Floresta, MT. The characterization of genotypes was performed through 30 morphological characteristics of flowers and fruits, 21 of these for flower and 9 for fruit. Data were evaluated using the principal components and cluster methods obtained by UPGMA method from the similarity matrix (Euclidian mean distance, using the Genes software. By principal component analysis, it has been found that the first three components have absorbed 52.11% of the accumulated variation. The characteristics that most contributed to the discrimination of genotypes were fresh fruit weight, stigma length, length of corona filaments, fruit width, petal width and pulp weight, which are more responsive for the selection of P.cristalina genotypes. Smaller contributions to diversity were obtained from anther width, bract width and fruit length. The smallest contributions for diversity were obtained from the following characteristics: anther width, bract width and fruit length. Through UPGMA clustering method, it was found that there is a large genetic divergence among genotypes analyzed because all genotypes were grouped with over 50% of dissimilarity. This study identified genotypes 4, 5 and 9 as the most divergent and therefore the most suitable for breeding in future breeding programs and genetic conservation of the species.

  10. Comparative transcript profiling of alloplasmic male-sterile lines revealed altered gene expression related to pollen development in rice (Oryza sativa L.).

    Science.gov (United States)

    Hu, Jihong; Chen, Guanglong; Zhang, Hongyuan; Qian, Qian; Ding, Yi

    2016-08-05

    Cytoplasmic male sterility (CMS) is an ideal model for investigating the mitochondrial-nuclear interaction and down-regulated genes in CMS lines which might be the candidate genes for pollen development in rice. In this study, a set of rice alloplasmic sporophytic CMS lines was obtained by successive backcrossing of Meixiang B, with three different cytoplasmic types: D62A (D type), ZS97A (WA type) and XQZ-A (DA type). Using microarray, the anther transcript profiles of the three indica rice CMS lines revealed 622 differentially expressed genes (DEGs) in each of the three CMS lines compared with the maintainer line Meixiang B. GO and MapMan analysis indicated that these DEGs were mainly involved in lipid metabolism and cell wall organization. Compared with the gene expression of sporophytic and gametophytic CMS lines, 303 DEGs were identified and 56 of them were down-regulated in all the CMS lines of rice. These down-regulated DEGs in the CMS lines were found to be involved in tapetum or cell wall formation and their suppressed expression might be related to male sterility. Weighted gene co-expression network analysis (WGCNA) revealed that two modules were significantly associated with male sterility and many hub genes that were differentially expressed in the CMS lines. A large set of putative genes involved in anther development was identified in the present study. The results will give some information for the nuclear gene regulation by different cytoplasmic genotypes and provide a rich resource for further functional research on the pollen development in rice.

  11. Development of In Vitro Systems for Switchgrass (Panicum virgatum) - Final Report for 1992 to 2002

    Energy Technology Data Exchange (ETDEWEB)

    Conger, B.V.

    2003-01-16

    Our project began on July 1, 1992, with the objective of developing systems that could be used in biotechnological approaches to switchgrass improvement. Within six months after initiation of the project, we had worked out protocols in which plants could be regenerated from callus cultures through both organogenesis and somatic embryogenesis. Documentation for both modes of regeneration was provided in our progress reports and in publications. One thousand regenerated plants were established in the field during the first year. We found that Alamo (lowland type) was much more amenable to in vitro culture, and plants could be regenerated much more easily than from Cave-in-Rock (upland type). During the first three years of the project, we studied the influence of genotype, culture medium components, explant type, etc., on regeneration. As mentioned, we found that the lowland cultivars Alamo and Kanlow were much easier to regenerate than upland cultivars, such as Trailblazer, Blackwell, and Cave-in-Rock. For callus induction, we initially used mature caryopses, young leaf tissue, and portions of seedlings. We were successful in inducing callus and regenerating plants from all explants. Two other systems developed during the 4th to 6th year period of the project included multiple shoot formation initiated from germinated seedlings and regenerable suspension cultures. The latter were initiated from embryogenic calluses produced from in vitro developed inflorescences. An important factor for producing multiple shoots was the presence of thidiazuron in the medium. The shoots could be easily rooted and numerous plantlets produced. The last 3 to 4 years of the project focused on anther and microspore culture experiments to produce haploid plants and on genetic transformation. Although thousands of putative haploid plants were produced from a few anthers, they were very weak and difficult to keep alive. Chromosome counts revealed the gametic number in cells where it was

  12. Diversidad de orbículas en Poaceae

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    Marcelo R Lovisolo

    2012-06-01

    Full Text Available Anteras de diez especies de Poaceae de la Provincia de Buenos Aires (Argentina fueron investigadas con microscopio electrónico de barrido y de transmisión. Las orbículas pueden ser definidas como corpúsculos de tamaño variable que muestran la misma electrodensidad, reacción a los colorantes, autofluorescencia y resistencia a la acetólisis que la exina del grano de polen. Las orbículas se encuentran revistiendo el interior del lóculo de la antera, a menudo adheridas a una membrana tapetal. En este estudio se identificaron cuatro tipos y cuatro subtipos diferentes de orbículas. Se concluye que los distintos tipos morfológicos de orbículas descriptos en este trabajo son representativos de cada una de las tribus estudiadas, por lo que se sugiere que la morfología de estos corpúsculos podría ser un carácter utilizado en estudios sistemáticos.Orbicules diversity in Poaceae. Anthers of ten species of Poaceae from the province of Buenos Aires (Argentina were investigated with scanning and transmission electron microscopes. The orbicules can be defined as corpuscles of variable size that show the same electron-density, reaction to the dyes, autofluorescence and resistance to acetolysis as pollen exine does. The orbicules are randomly dispersed on the inner anther locule and they are often attached to a tapetal membrane. In this study, four different types and four subtypes of orbicules were identified. We conclude that the different orbicules types described in this work are representative of the studied tribes, and we suggest that the orbicules morphology may be a useful character in systematic studies.

  13. Gibberellin Induces Diploid Pollen Formation by Interfering with Meiotic Cytokinesis.

    Science.gov (United States)

    Liu, Bing; De Storme, Nico; Geelen, Danny

    2017-01-01

    The plant hormone gibberellic acid (GA) controls many physiological processes, including cell differentiation, cell elongation, seed germination, and response to abiotic stress. In this study, we report that exogenous treatment of flowering Arabidopsis (Arabidopsis thaliana) plants with GA specifically affects the process of male meiotic cytokinesis leading to meiotic restitution and the production of diploid (2n) pollen grains. Similar defects in meiotic cell division and reproductive ploidy stability occur in Arabidopsis plants depleted of RGA and GAI, two members of the DELLA family that function as suppressor of GA signaling. Cytological analysis of the double rga-24 gai-t6 mutant revealed that defects in male meiotic cytokinesis are not caused by alterations in meiosis I (MI or meiosis II (MII) chromosome dynamics, but instead result from aberrations in the spatial organization of the phragmoplast-like radial microtubule arrays (RMAs) at the end of meiosis II. In line with a role for GA in the genetic regulation of the male reproductive system, we additionally show that DELLA downstream targets MYB33 and MYB65 are redundantly required for functional RMA biosynthesis and male meiotic cytokinesis. By analyzing the expression of pRGA::GFP-RGA in the wild-type Landsberg erecta background, we demonstrate that the GFP-RGA protein is specifically expressed in the anther cell layers surrounding the meiocytes and microspores, suggesting that appropriate GA signaling in the somatic anther tissue is critical for male meiotic cell wall formation and thus plays an important role in consolidating the male gametophytic ploidy consistency. © 2017 American Society of Plant Biologists. All Rights Reserved.

  14. Reproductive studies in ipecac (Psychotria ipecacuanha (Brot. stockes; Rubiaceae: pollen development and morphology

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    Margarete Magalhães Souza

    2008-10-01

    Full Text Available The aim of this work was to carry out the reproductive studies on Brazilian accessions of ipecac, Psychotria ipecacuanha. It presented heterostyly, with brevistylous and longistylous flowers. The pollen development was observed from the sections of the anthers embedded in resin. Anther development was normal as usually observed in dicotyledones, displaying four layers: outer epidermis, endothecium, middle layer and inner tapetum. The pollen was bicellular and filled with starch at the microspore stage. Pollen morphology was studied using SEM, which showed pollen polymorphism within and between the two floral morphs. Five types of pollen with reticulate or perforate exine were identified. The characteristics showed that the sexual process was as important as the vegetative propagation for the reproduction of this species.Foram realizados estudos reprodutivos em acessos brasileiros de poaia, Psychotria ipecacuanha. Poaia apresenta heterostilia, com flores brevistilas e longistilas. O desenvolvimento do pólen foi estudado em cortes de anteras embebidas em resina. O desenvolvimento da antera seguiu o padrão normal para as dicotiledôneas, a qual apresentou quatro camadas: epiderme, endotécio, camada média, e tapete, a mais interna. O pólen apresentou-se bicelular e preenchido com amido no estágio de micrósporo. A morfologia do pólen foi estudada utilizando-se MEV. Foi observado polimorfismo polínico dentro e entre as duas formas florais. Foram identificados cinco tipos de grãos de pólen, com exina reticulada ou perfurada. Em seu hábitat natural, sabe-se que essa espécie apresenta propagação por multiplicação vegetativa, mas as características estudadas demonstraram que o mecanismo sexuado é tão importante para a reprodução dessa espécie quanto à propagação vegetativa.

  15. The Rice AAA-ATPase OsFIGNL1 Is Essential for Male Meiosis

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    Peipei Zhang

    2017-09-01

    Full Text Available Meiosis is crucial in reproduction of plants and ensuring genetic diversity. Although several genes involved in homologous recombination and DNA repair have been reported, their functions in rice (Oryza sativa male meiosis remain poorly understood. Here, we isolated and characterized the rice OsFIGNL1 (OsFidgetin-like 1 gene, encoding a conserved AAA-ATPase, and explored its function and importance in male meiosis and pollen formation. The rice Osfignl1 mutant exhibited normal vegetative growth, but failed to produce seeds and displayed pollen abortion phenotype. Phenotypic comparisons between the wild-type and Osfignl1 mutant demonstrated that OsFIGNL1 is required for anther development, and that the recessive mutation of this gene causes male sterility in rice. Complementation and CRISPR/Cas9 experiments demonstrated that wild-type OsFIGNL1 is responsible for the male sterility phenotype. Subcellular localization showed that OsFIGNL1-green fluorescent protein was exclusively localized in the nucleus of rice protoplasts. Male meiosis in the Osfignl1 mutant exhibited abnormal chromosome behavior, including chromosome bridges and multivalent chromosomes at diakinesis, lagging chromosomes, and chromosome fragments during meiosis. Yeast two-hybrid assays demonstrated OsFIGNL1 could interact with RAD51A1, RAD51A2, DMC1A, DMC1B, and these physical interactions were further confirmed by BiFC assay. Taken together, our results suggest that OsFIGNL1 plays an important role in regulation of male meiosis and anther development.

  16. [Anatomy and development of stamens and carpels of Drimys granadensis (Winteraceae)].

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    Marquínez-Casas, Xavier

    2014-09-01

    Winteraceae has long been considered a family with early diversification among angiosperms, with characters such as: flowers with many spirally arranged parts and apocarpic ovary formed by plicated carpels with sessile stigma. In Drimys, the presence or absence of conspicuous glands on the connective of the stamens have been used as a taxonomic character, and it is considered a synapomorphy for the clade including Drimys angustifolia, D. brasiliensis, D. granadensis and D. roraimensis (Northeastern clade); however, the anatomy of stamens and carpels has only been studied in detail for D. winteri (Southwestern clade). In this research, the presence and the structure of glands on the connective of stamens was studied in seven species of the genus from herbarium specimens, and a detailed study of the anatomy and development of stamens and carpels was carried out by scanning electron and optic microscopy in Drimys granadensis. We found similarities between D. granadensis and D. winteri for the following characters: Basic type anther wall formation, secretory tapetum that collapses at maturity, intermediate type microsporogenesis with formation of a transient cell plate in telophase I, ascidiated carpel due to the formation of an adaxial lip during development, stigma closed by interdigitation of epidermal cells. We also determined that the large glands on anther mature connective are originated by an overgrowth of subepidermal oil cells; this character is a Northeastern Drimys clade synapomorphy, while it was absent in both Drimys of Southwestern clade (which includes D. andina, D. confertifolia and D. winteri), and the rest of the Winteraceae. We are proposing the hypothesis that the highly variable enviromental conditions in the tropics where Drimys Northeastern clade is distributed, with a wide range of pollinators, would be associated with the emergence of glandular conspicuously stamens; while, as a prediction to be confirmed, temperated Southwestern clade species

  17. The simultaneous repression of CCR and CAD, two enzymes of the lignin biosynthetic pathway, results in sterility and dwarfism in Arabidopsis thaliana.

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    Thévenin, Johanne; Pollet, Brigitte; Letarnec, Bruno; Saulnier, Luc; Gissot, Lionel; Maia-Grondard, Alessandra; Lapierre, Catherine; Jouanin, Lise

    2011-01-01

    Cinnamoyl CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD) catalyze the last steps of monolignol biosynthesis. In Arabidopsis, one CCR gene (CCR1, At1g15950) and two CAD genes (CAD C At3g19450 and CAD D At4g34230) are involved in this pathway. A triple cad c cad d ccr1 mutant, named ccc, was obtained. This mutant displays a severe dwarf phenotype and male sterility. The lignin content in ccc mature stems is reduced to 50% of the wild-type level. In addition, stem lignin structure is severely affected, as shown by the dramatic enrichment in resistant inter-unit bonds and incorporation into the polymer of monolignol precursors such as coniferaldehyde, sinapaldehyde, and ferulic acid. Male sterility is due to the lack of lignification in the anther endothecium, which causes the failure of anther dehiscence and of pollen release. The ccc hypolignified stems accumulate higher amounts of flavonol glycosides, sinapoyl malate and feruloyl malate, which suggests a redirection of the phenolic pathway. Therefore, the absence of CAD and CCR, key enzymes of the monolignol pathway, has more severe consequences on the phenotype than the individual absence of each of them. Induction of another CCR (CCR2, At1g80820) and another CAD (CAD1, At4g39330) does not compensate the absence of the main CCR and CAD activities. This lack of CCR and CAD activities not only impacts lignification, but also severely affects the development of the plants. These consequences must be carefully considered when trying to reduce the lignin content of plants in order to facilitate the lignocellulose-to-bioethanol conversion process.

  18. Breaking-bud pollination: a new pollination process in partially opened flowers by small bees.

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    Yamaji, Futa; Ohsawa, Takeshi A

    2015-09-01

    Plant-pollinator interactions have usually been researched in flowers that have fully opened. However, some pollinators can visit flowers before full opening and contribute to fruit and seed sets. In this paper, we researched the pollination biology of flowers just starting to open in four field experiments. We observed the insect visitors to Lycoris sanguinea var. sanguinea for 3 years at five sites. These observations revealed that only small bees, Lasioglossum japonicum, often entered through tiny spaces between the tepals of 'breaking buds' (i.e. partially opened flowers) and collected pollen. We hypothesized that they can pollinate this species at the breaking-bud stage, when the stigma is located near the anthers. To measure the pollination effect of small bees at the breaking-bud stage, we bagged several breaking buds after small bees had visited them and examined whether these buds were pollinated. In bagging experiments, 30% of the breaking buds set fruit and seeds. Fruit-set ratios of the breaking buds did not differ significantly from those of the fully opened flowers, which had been visited by several insect species. We also counted the pollen grain numbers on the body of L. japonicum and on the anthers of randomly-selected and manipulated flowers. These experiments revealed that all of the captured bees had some pollen of target plants and that L. japonicum collected most of the pollen grains at the breaking-bud stage. Our results showed that the new pollination process, breaking-bud pollination, happened in breaking buds by L. japonicum, although there is no evidence to reveal that this is the most effective pollination method for L. sanguinea var. sanguinea. In principle, this new pollination process can occur in other flowering plants and our results are a major contribution to studies of plant-pollinator interactions.

  19. Early embryo achievement through isolated microspore culture in Citrus clementina Hort. ex Tan., cvs. ‘Monreal Rosso’ and ‘Nules’

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    Benedetta eChiancone

    2015-06-01

    Full Text Available Microspore embryogenesis is a method of achieving complete homozygosity from plants. It is particularly useful for woody species, like Citrus, characterized by long juvenility, a high degree of heterozygosity and often self-incompatibility. Anther culture is currently the method of choice for microspore embryogenesis in many crops. However, isolated microspore culture is a better way to investigate the processes at the cellular, physiological, biochemical and molecular levels as it avoids the influence of somatic anther tissue. To exploit the potential of this technique, it is important to separate the key factors affecting the process and, among them, culture medium composition and particularly the plant growth regulators and their concentration, as they can greatly enhance regeneration efficiency. To our knowledge, the ability of meta-Topolin, a naturally occurring aromatic cytokinin, to induce gametic embryogenesis in isolated microspores of Citrus has never been investigated. In this study, the effect of two concentrations of meta-Topolin instead of benzyladenine or zeatin in the culture medium was investigated in isolated microspore culture of two genotypes of Citrus. After eleven months of isolated microspore culture, for both genotypes and for all the four tested media, the microspore reprogramming and their sporophytic development was observed by the presence of multinucleated calli and microspore-derived embryos at different stages. Microsatellite analysis of parental and embryo samples was performed to determine the embryo alleles constitution of early embryos produced in all tested media, confirming their origin from microspores.To our knowledge, this is the first successful report of Citrus microspore embryogenesis with isolated microspore culture in Citrus, and in particular in Citrus clementina Hort. ex Tan, cvs. ‘Monreal Rosso’ and ‘Nules’.

  20. Variation in expression of trimorphic incompatibility in Pontederia cordata L. (Pontederiaceae).

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    Barrett, S C; Anderson, J M

    1985-07-01

    Pontederia cordata L. (Pontederiaceae), a perennial diploid, possesses the rare genetic polymorphism tristyly. A controlled pollination programme was conducted over a three year period, under glasshouse conditions, on 36 clones of P. cordata var. cordata to examine the nature of the self-incompatibility system. The three major findings of the pollination study were: (1) the three floral morphs display different levels of self-incompatibility, (2) pollen from the two anther levels within a flower exhibits different compatibility behaviour in self-pollinations, (3) considerable individual genetic variation in the expression of self-incompatibility is evident among clones within floral morphs. Similar results were also obtained from a smaller study on 15 clones of P. cordata var. lancifolia conducted over a 6 month period. In common with other Pontederia species the mid-styled morph (M) of P. cordata produces large amounts of seed when self-pollinated with pollen from long-level anthers. A developmental model is proposed to explain the high level of self-compatibility of the M morph in Pontederia species. Self-pollination of segregating progenies from M and S morphs of known incompatibility status demonstrated that the expression of incompatibility is closely associated with style length. It is suggested that overall differences in incompatibility behaviour among the floral morphs may be due to the pleiotropic effects of major genes controlling sub-characters of the tristylous syndrome, rather than linked modifier genes. However, the variable expression of trimorphic incompatibility within floral morphs suggests that this variation may be polygenic in origin.

  1. Cytological and transcriptional dynamics analysis of host plant revealed stage-specific biological processes related to compatible rice-Ustilaginoidea virens interaction.

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    Jinquan Chao

    Full Text Available Rice false smut, a fungal disease caused by Ustilaginoidea virens is becoming a severe detriment to rice production worldwide. However, little is known about the molecular response of rice to attacks by the smut pathogen. In this article, we define the initial infection process as having three stages: initial colonization on the pistil (stage 1, S1, amplification on the anther (stage 2, S2 and sporulation in the anther chambers (stage 3, S3. Based on the transcriptome of rice hosts in response to U. virens in two separate years, we identified 126, 204, and 580 specific regulated genes in their respective stages S1, S2, and S3, respectively, by excluding common expression patterns in other openly biotic/abiotic databases using bioinformatics. As the disease progresses, several stage-specific biological processes (BP terms were distinctively enriched: "Phosphorylation" in stage S1, "PCD" in S2, and "Cell wall biogenesis" in S3, implying a concise signal cascade indicative of the tactics that smut pathogens use to control host rice cells during infection. 113 regulated genes were coexpressed among the three stages. They shared highly conserved promoter cis-element in the promoters in response to the regulation of WRKY and Myb for up-regulation, and ABA and Ca2+ for down regulation, indicating their potentially critical roles in signal transduction during rice-U. virens interaction. We further analyzed seven highly regulated unique genes; four were specific to pollen development, implying that pollen-related genes play critical roles in the establishment of rice susceptibility to U. virens. To my knowledge, this is the first report about probing of molecular response of rice to smut pathogen infection, which will greatly expand our understanding of the molecular events surrounding infection by rice false smut.

  2. Illuminating a plant's tissue-specific metabolic diversity using computational metabolomics and information theory.

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    Li, Dapeng; Heiling, Sven; Baldwin, Ian T; Gaquerel, Emmanuel

    2016-11-22

    Secondary metabolite diversity is considered an important fitness determinant for plants' biotic and abiotic interactions in nature. This diversity can be examined in two dimensions. The first one considers metabolite diversity across plant species. A second way of looking at this diversity is by considering the tissue-specific localization of pathways underlying secondary metabolism within a plant. Although these cross-tissue metabolite variations are increasingly regarded as important readouts of tissue-level gene function and regulatory processes, they have rarely been comprehensively explored by nontargeted metabolomics. As such, important questions have remained superficially addressed. For instance, which tissues exhibit prevalent signatures of metabolic specialization? Reciprocally, which metabolites contribute most to this tissue specialization in contrast to those metabolites exhibiting housekeeping characteristics? Here, we explore tissue-level metabolic specialization in Nicotiana attenuata, an ecological model with rich secondary metabolism, by combining tissue-wide nontargeted mass spectral data acquisition, information theory analysis, and tandem MS (MS/MS) molecular networks. This analysis was conducted for two different methanolic extracts of 14 tissues and deconvoluted 895 nonredundant MS/MS spectra. Using information theory analysis, anthers were found to harbor the most specialized metabolome, and most unique metabolites of anthers and other tissues were annotated through MS/MS molecular networks. Tissue-metabolite association maps were used to predict tissue-specific gene functions. Predictions for the function of two UDP-glycosyltransferases in flavonoid metabolism were confirmed by virus-induced gene silencing. The present workflow allows biologists to amortize the vast amount of data produced by modern MS instrumentation in their quest to understand gene function.

  3. Is pollen removal or seed set favoured by flower longevity in a hummingbird-pollinated Salvia species?

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    Aximoff, Izar Araujo; Freitas, Leandro

    2010-09-01

    The period between the beginning of anthesis and flower senescence modulates the transport of pollen by pollinators among conspecific flowers, and its length may therefore influence reproductive success. This study evaluated whether floral longevity favours pollen removal from the anthers over fecundity (seed set) in an ornithophilous species that does not undergo pollen limitation. Field investigations were conducted on floral longevity, nectar production, pollinator behaviour, and variations in fruit set (FS), mean number of seeds per fruit (MSF) and pollen removal by hummingbirds (PR) during the anthesis of Salvia sellowiana in south-east Brazil. Anthesis of flowers exposed to pollinators lasted 4 d, as well as on flowers with pollen removed from the anthers or deposited on the stigma. The longevity of bagged flowers was significantly higher (approx. 9 d). FS and PR reached 87.2 and 90 %, respectively, in natural conditions. PR increased gradually over the period of anthesis; however, FS and MSF reached their maxima in the first hours of anthesis. Nectar production was continuous, but the secretion rate was reduced after pollination. The removal of nectar from non-pollinated flowers stimulated its production. The longevity of anthesis in S. sellowiana seems to be related to the mechanism of gradual dispensing of pollen, resulting in greater male reproductive success. This is in agreement with the pollen-donation hypothesis. The small number of ovules (four) of S. sellowiana and the high frequency and the foraging mode of its pollinators may favour the selection for floral longevity driven by male fitness in this system.

  4. The role of short-tongued insects in floral variation across the range of a style-dimorphic plant.

    Science.gov (United States)

    Santos-Gally, Rocío; Pérez-Barrales, Rocío; Simón, Violeta I; Arroyo, Juan

    2013-02-01

    Heterostyly and related style polymorphisms are suitable model systems to evaluate the importance of functional pollinators in the maintenance of population variability. In Narcissus papyraceus different functional pollinators, incompatibility system and flower morphology have been proposed to influence the maintenance of polymorphism through their effect on disassortative mating. Here a test is done to find out if the visitation rate of long- versus short-tongued pollinators correlates with the morph ratio and if the latter is related to other flower traits of the species across its main geographic range. Floral traits from 34 populations in the south-west of the Iberian Peninsula and in north-west Africa were measured, perianth variation was described and a comparison was made of allometric relationships between sex organs and floral tube. Correlations between pollinator guilds, stigma-anther separation of reciprocal morphs (our proxy for disassortative mating) and morph-ratio variation were analysed. Finally, the incompatibility system of the species in the northern and southern borders of its distribution are described. Flowers from southern populations were significantly larger than flowers from centre and northern populations. The abundance of short-styled plants decreased gradually with increasing distance from the core region (the Strait of Gibraltar), with these disappearing only in the northern range. Although there was a significant difference in stigma-anther separation among populations, morph ratio was not associated with reciprocity or floral tube length. Long-style morph frequency increased with short-tongued pollinator visitation rate. Populations from both edges of the distribution range were self-incompatible and within- and between-morph compatible. The style morph ratio changed gradually, whereas perianth trait variation showed abrupt changes with two morphotypes across the range. The positive relationship between the visitation rate of short

  5. Inside-out flowers of Lacandonia brasiliana (Triuridaceae provide new insights into fundamental aspects of floral patterning

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    Paula J. Rudall

    2016-02-01

    Full Text Available Background and Aims. A recently described Brazilian species, Lacandonia brasiliana, shares with its longer established putative sister species from Mexico, L. schismatica, inverted floral patterning (carpels surrounding stamens that is almost unique among angiosperms. We present a detailed ontogenetic study of L. brasiliana for comparison with other members of the tribe Triurideae (Triuridaceae to explore the possible evolutionary origins of “inside-out” flowers. Methods. Wild-source populations of L. brasiliana were compared morphologically and ontogenetically with related species of Triurideae, using light and scanning electron microscopy. Key Results. Relatively few morphological differences separate flowers of L. brasiliana and L. schismatica. Both species have tepals with late-developing subapical appendages. In both species, the three central (almost sessile anthers develop precociously with respect to the carpels; the anthers remain closed, and fertilization is achieved via pollen-tube growth from germinating pollen grains of the same cleistogamous flower. Carpels are initiated on fascicles. Conclusions. The close similarity between the two Lacandonia species makes it unlikely that they arose independently from two separate homeotic transformation events; they could either represent sister species or two populations of a single disjunct species. Our study underlines the problematic generic and species boundaries within Triurideae. We present an evolutionary scenario of character evolution in Triuridaceae. The inside-out Lacandonia flower could have resulted from a stabilized homeotic transformation; this hypothesis is not in conflict with constrasting theories of the origin of the Triuridaceae flower, which coincided with a shift to unisexuality. The unisexual yet highly plastic flowers that are typical of Triuridaceae could have pre-adapted the origin of the extraordinary Lacandonia morphology.

  6. Turbulence-induced resonance vibrations cause pollen release in wind-pollinated Plantago lanceolata L. (Plantaginaceae).

    Science.gov (United States)

    Timerman, David; Greene, David F; Urzay, Javier; Ackerman, Josef D

    2014-12-06

    In wind pollination, the release of pollen from anthers into airflows determines the quantity and timing of pollen available for pollination. Despite the ecological and evolutionary importance of pollen release, wind-stamen interactions are poorly understood, as are the specific forces that deliver pollen grains into airflows. We present empirical evidence that atmospheric turbulence acts directly on stamens in the cosmopolitan, wind-pollinated weed, Plantago lanceolata, causing resonant vibrations that release episodic bursts of pollen grains. In laboratory experiments, we show that stamens have mechanical properties corresponding to theoretically predicted ranges for turbulence-driven resonant vibrations. The mechanical excitation of stamens at their characteristic resonance frequency caused them to resonate, shedding pollen vigorously. The characteristic natural frequency of the stamens increased over time with each shedding episode due to the reduction in anther mass, which increased the mechanical energy required to trigger subsequent episodes. Field observations of a natural population under turbulent wind conditions were consistent with these laboratory results and demonstrated that pollen is released from resonating stamens excited by small eddies whose turnover periods are similar to the characteristic resonance frequency measured in the laboratory. Turbulence-driven vibration of stamens at resonance may be a primary mechanism for pollen shedding in wind-pollinated angiosperms. The capacity to release pollen in wind can be viewed as a primary factor distinguishing animal- from wind-pollinated plants, and selection on traits such as the damping ratio and flexural rigidity may be of consequence in evolutionary transitions between pollination systems. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  7. Transitions from distyly to homostyly are associated with floral evolution in the buckwheat genus (Fagopyrum).

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    Wu, Ling-Yun; Wang, Bo; Schoen, Daniel J; Huang, Shuang-Quan

    2017-08-08

    Documenting trait transitions among species with dimorphic flowers can help to test whether similar patterns of selection are responsible for divergence in floral traits among different species. Heterostyly is thought to promote outcrossing. Theory suggests that the evolutionary transition from heterostylous to homostylous flowers should be accompanied by a reduction in floral size in which pollen size and style length are expected to covary. Patterns of such correlated floral trait evolution have not, however, been widely examined. The evolutionary history of heterostyly and homostyly was reconstructed from a molecular phylogeny of 13 species of Fagopyrum and two outgroups, based on one nuclear gene (nrITS) and three chloroplast regions ( matK , atpB-rbcL , and psbA-trnH spacer). Floral traits of nine Fagopyrum species including pollen number and size, as well as stigma depth (length of the capitate stigma), were measured and ancestral characters of the herkogamic condition were reconstructed. Three transitions from distyly to homostyly were observed. In two transitions, flower size (corolla diameter, pedicel length), herkogamy (stigma-anther distance) and pollen production decreased, but stigma depth and pollen size did not. Changes of anther height and style length were inconsistent. The predicted positive relationship between style length and pollen size in the two transitions to homostyly was not observed. Floral evolution accompanying transitions to homostyly in Fagopyrum were found to be consistent with predictions of mating system evolution theory, and the correlation of traits in distylous vs. homostylous species revealed that pollen size generally correlates with stigma depth rather than style length. © 2017 Botanical Society of America.

  8. Molecular identification of tuliposide B-converting enzyme: a lactone-forming carboxylesterase from the pollen of tulip.

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    Nomura, Taiji; Murase, Tatsunori; Ogita, Shinjiro; Kato, Yasuo

    2015-07-01

    6-Tuliposides A (PosA) and B (PosB), which are the major secondary metabolites in tulip (Tulipa gesneriana), are enzymatically converted to the antimicrobial lactonized aglycons, tulipalins A (PaA) and B (PaB), respectively. We recently identified a PosA-converting enzyme (TCEA) as the first reported member of the lactone-forming carboxylesterases. Herein, we describe the identification of another lactone-forming carboxylesterase, PosB-converting enzyme (TCEB), which preferentially reacts with PosB to give PaB. This enzyme was isolated from tulip pollen, which showed high PosB-converting activity. Purified TCEB exhibited greater activity towards PosB than PosA, which was contrary to that of the TCEA. Novel cDNA (TgTCEB1) encoding the TCEB was isolated from tulip pollen. TgTCEB1 belonged to the carboxylesterase family and was approximately 50% identical to the TgTCEA polypeptides. Functional characterization of the recombinant enzyme verified that TgTCEB1 catalyzed the conversion of PosB to PaB with an activity comparable with the native TCEB. RT-qPCR analysis of each part of plant revealed that TgTCEB1 transcripts were limited almost exclusively to the pollen. Furthermore, the immunostaining of the anther cross-section using anti-TgTCEB1 polyclonal antibody verified that TgTCEB1 was specifically expressed in the pollen grains, but not in the anther cells. N-terminal transit peptide of TgTCEB1 was shown to function as plastid-targeted signal. Taken together, these results indicate that mature TgTCEB1 is specifically localized in plastids of pollen grains. Interestingly, PosB, the substrate of TgTCEB1, accumulated on the pollen surface, but not in the intracellular spaces of pollen grains. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  9. LAP6/POLYKETIDE SYNTHASE A and LAP5/POLYKETIDE SYNTHASE B Encode Hydroxyalkyl α-Pyrone Synthases Required for Pollen Development and Sporopollenin Biosynthesis in Arabidopsis thaliana[C][W][OA

    Science.gov (United States)

    Kim, Sung Soo; Grienenberger, Etienne; Lallemand, Benjamin; Colpitts, Che C.; Kim, Sun Young; Souza, Clarice de Azevedo; Geoffroy, Pierrette; Heintz, Dimitri; Krahn, Daniel; Kaiser, Markus; Kombrink, Erich; Heitz, Thierry; Suh, Dae-Yeon; Legrand, Michel; Douglas, Carl J.

    2010-01-01

    Plant type III polyketide synthases (PKSs) catalyze the condensation of malonyl-CoA units with various CoA ester starter molecules to generate a diverse array of natural products. The fatty acyl-CoA esters synthesized by Arabidopsis thaliana ACYL-COA SYNTHETASE5 (ACOS5) are key intermediates in the biosynthesis of sporopollenin, the major constituent of exine in the outer pollen wall. By coexpression analysis, we identified two Arabidopsis PKS genes, POLYKETIDE SYNTHASE A (PKSA) and PKSB (also known as LAP6 and LAP5, respectively) that are tightly coexpressed with ACOS5. Recombinant PKSA and PKSB proteins generated tri-and tetraketide α-pyrone compounds in vitro from a broad range of potential ACOS5-generated fatty acyl-CoA starter substrates by condensation with malonyl-CoA. Furthermore, substrate preference profile and kinetic analyses strongly suggested that in planta substrates for both enzymes are midchain- and ω-hydroxylated fatty acyl-CoAs (e.g., 12-hydroxyoctadecanoyl-CoA and 16-hydroxyhexadecanoyl-CoA), which are the products of sequential actions of anther-specific fatty acid hydroxylases and acyl-CoA synthetase. PKSA and PKSB are specifically and transiently expressed in tapetal cells during microspore development in Arabidopsis anthers. Mutants compromised in expression of the PKS genes displayed pollen exine layer defects, and a double pksa pksb mutant was completely male sterile, with no apparent exine. These results show that hydroxylated α-pyrone polyketide compounds generated by the sequential action of ACOS5 and PKSA/B are potential and previously unknown sporopollenin precursors. PMID:21193570

  10. Implementation and Evaluation of an Image Analysis System for Determining Viability of Pollen Grains in Temperate Rice Implementación y Evaluación de un Sistema de Análisis de Imagen para determinar la Viabilidad de Granos de Polen en Arroz Templado

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    Rodrigo Ortega B

    2011-03-01

    Full Text Available Geographical and climatic factors limit the production of temperate rice (Oryza sativa L. in Chile. Large thermal fluctuations of air and water temperatures affect the viability of pollen, causing high levels of spikelet sterility (”blanking”, resulting in reduced yields per hectare. Counting viable pollen grains, at the time of anthesis, may allow determining, ahead, whether there will be yield losses by spikelet sterility; besides, knowing the potential pollen viability serves as a powerful tool for material selection in breeding programs, and for determining which management factors may influence ”blanking”. If performed manually, counting total and viable pollen grains can be extremely tedious, producing highly variable results. The present work had for objectives to develop and evaluate a system, based on imagery analysis, for counting total and viable pollen in rice anthers. At the time of anthesis, three panicles were collected from plot treatments of two field experiments in which the effects of different management factors (variety, water height, N rate, and spatial arrangement on spikelet sterility were evaluated. Two spikelets and four anthers were sampled from each panicle; pollen grains were extracted from anthers and photographed. Manual and digital counts were made on the images to determine total and viable pollen. Digital count was performed with the software SigmaScan Pro, setting some parameters on the imagery before counting. Precision and accuracy of the digital method were estimated. The results indicated that the digital pollen count showed a very good precision and accuracy and could be used to estimate pollen viability, and as a response variable to compare management treatments.La producción de arroz (Oryza sativa L. en Chile está limitada principalmente por factores geográficos y climáticos. Las grandes variaciones de temperatura del agua y del aire afectan la viabilidad del polen, causando altos niveles de

  11. Polimorfismo floral em Valeriana scandens L. (Valerianaceae Floral polymorphism in Valeriana scandens L. (Valerianaceae

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    Erica Duarte-Silva

    2010-09-01

    Full Text Available Foram encontrados três morfos florais em Valeriana scandens L.: flor perfeita, flor pistilada 1 e flor pistilada 2. A perfeita possui corola maior que a dos demais morfos, com lobos reflexos na antese, giba proeminente e localizada na porção proximal do tubo floral; anteras maiores que as dos demais morfos, com pólen viável; estilete curto e estigma incluso, o menor ovário e saco embrionário estruturalmente normal, semelhante ao dos demais morfos. A pistilada 1 possui a giba menos proeminente, corola de tamanho intermediário em relação aos demais morfos, lobos radiais na antese; anteras pequenas, sem pólen e estilete longo e estigma exserto. A pistilada 2 possui lobos radiais na antese, anteras de comprimento semelhante às da perfeita, mas de menor largura, com pólen inviável; estilete mais curto, tal como o da flor perfeita, e estigma exserto, tal como o da flor pistilada 1. Nos três morfos, o nectário é formado por tricomas secretores unicelulares situados na epiderme da face interna da giba, e suas sementes são viáveis. As flores pistilada 2 e perfeita apresentam um septo que isola a giba do restante do tubo floral, formando uma câmara nectarífera. V. scandens L. é ginomonóica-ginodióica, expressão sexual inédita em Valerianaceae.Three floral morphs were found in Valeriana scandens L.: perfect, pistillate 1, and pistillate 2. In perfect flowers, the corolla is longer than in the other morphs, with reflexed lobes at anthesis and a prominent gibbus at the tube base; anthers are longer and contain viable pollen grains; the pistil has a short included style/stigma and the smallest ovary, but a structurally normal embryo sac similar to that of the other morphs. In pistillate 1 flowers, the corolla is intermediate in size, and has radially displayed lobes at anthesis, and a softly prominent gibbus; anthers are small and devoid of pollen; the pistil shows a long exerted style/stigma. In pistillate 2 flowers, the corolla

  12. Genes of the most conserved WOX clade in plants affect root and flower development in Arabidopsis

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    Moreau Hervé

    2008-10-01

    Full Text Available Abstract Background The Wuschel related homeobox (WOX family proteins are key regulators implicated in the determination of cell fate in plants by preventing cell differentiation. A recent WOX phylogeny, based on WOX homeodomains, showed that all of the Physcomitrella patens and Selaginella moellendorffii WOX proteins clustered into a single orthologous group. We hypothesized that members of this group might preferentially share a significant part of their function in phylogenetically distant organisms. Hence, we first validated the limits of the WOX13 orthologous group (WOX13 OG using the occurrence of other clade specific signatures and conserved intron insertion sites. Secondly, a functional analysis using expression data and mutants was undertaken. Results The WOX13 OG contained the most conserved plant WOX proteins including the only WOX detected in the highly proliferating basal unicellular and photosynthetic organism Ostreococcus tauri. A large expansion of the WOX family was observed after the separation of mosses from other land plants and before monocots and dicots have arisen. In Arabidopsis thaliana, AtWOX13 was dynamically expressed during primary and lateral root initiation and development, in gynoecium and during embryo development. AtWOX13 appeared to affect the floral transition. An intriguing clade, represented by the functional AtWOX14 gene inside the WOX13 OG, was only found in the Brassicaceae. Compared to AtWOX13, the gene expression profile of AtWOX14 was restricted to the early stages of lateral root formation and specific to developing anthers. A mutational insertion upstream of the AtWOX14 homeodomain sequence led to abnormal root development, a delay in the floral transition and premature anther differentiation. Conclusion Our data provide evidence in favor of the WOX13 OG as the clade containing the most conserved WOX genes and established a functional link to organ initiation and development in Arabidopsis, most

  13. AGROBACTERIUM-MEDIATED TRANSFORMATION OF WHEAT

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    K. Mészáros

    2008-09-01

    Full Text Available Transformation of cereals is one of the emerging areas for plant genomic and biotechnology research. Wheat was among the last major crops to be transformed by particle bombardment about 10 years ago. However, Agrobacterium-mediated transformation has several advantages over bombardment, including a reduction in copy number, fewer rearrangements and preferential integration into transcriptionally active chromosome regions. As a first step, we started to adapt an immature embryo-based transformation method for the model variety ‘Cadenza’. The regeneration of this variety was low and especially the cost of generating donor plants was high. Therefore, we decided (i to test regeneration capacity of winter and spring wheats using four different explants, (ii to determine the optimal genotype-regeneration system combinations, and (iii to work out the details of mature embryo transformation with Agrobacterium. The experiment was carried out with 16 cultivated winter wheat and 2 model spring wheat varieties. Four different explants: anther, immature embryo, mature embryo and dry seed were tested for callus induction and plant regeneration. The regeneration capacity was the lowest in the case of anther culture and ranged from 20% (‘Mv Béres’ to 0.1% (‘Mv Magvas’ with four varieties exerting significantly higher regeneration than ‘Cadenza’. Plant regeneration from immature embryos ranged between 59% (‘Mv Regiment’ and 0.1% (‘Mv Toborzó’. Again, four varieties produced significantly more plants than the control ‘Cadenza’. We tested two systems for the plant regeneration from mature embryos. First, mature embryos were isolated from seeds, which resulted in an average of 17% plant regeneration (from 63% in ‘Fatima’ to zero in ‘Mv Palotás’. ‘Cadenza’ was one of the worse regenerating genotype (7%. The highest plant regeneration (average 54% was in the case of seed explants. There were no significant differences

  14. Comparative Transcriptome Profile of the Cytoplasmic Male Sterile and Fertile Floral Buds of Radish (Raphanus sativus L.

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    Shiyong Mei

    2016-01-01

    Full Text Available Radish cytoplasmic male sterility (CMS has been widely used for breeding in Raphanus and Brassica genera. However, the detailed regulation network of the male sterility remains to be determined. Our previous work has shown that the abnormalities in a CMS radish appeared shortly after the tetrad stage when microspores were malformed and the tapetal cells grew abnormally large. In this work, histological analysis shows that anthers are at the tetrad stage when the radish buds are about 1.5 mm in length. Furthermore, a high throughput RNA sequencing technology was employed to characterize the transcriptome of radish buds with length about 1.5 mm from two CMS lines possessing the CMS-inducing orf138 gene and corresponding near-isogenic maintainer lines. A total of 67,140 unigenes were functionally annotated. Functional terms for these genes are significantly enriched in 55 Gene Ontology (GO groups and 323 Kyoto Encyclopedia of Genes and Genomes (KEGG pathways. The transcriptome detected transcripts for 72 out of a total of 79 protein genes encoded in the chloroplast genome from radish. In contrast, the radish mitochondrial genome contains 34 protein genes, but only 16 protein transcripts were detected from the transcriptome. The transcriptome comparison between CMS and near-isogenic maintainer lines revealed 539 differentially expressed genes (DEGs, indicating that the false positive rate for comparative transcriptome profiling was clearly decreased using two groups of CMS/maintainer lines with different nuclear background. The level of 127 transcripts was increased and 412 transcripts were decreased in the CMS lines. No change in levels of transcripts except CMS-inducing orf138 was identified from the mitochondrial and chloroplast genomes. Some DEGs which would be associated with the CMS, encoding MYB and bHLH transcription factors, pentatricopeptide repeat (PPR proteins, heat shock transcription factors (HSFs and heat shock proteins (HSPs, are

  15. Identification, functional characterization and developmental regulation of sesquiterpene synthases from sunflower capitate glandular trichomes

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    Ro Dae-Kyun

    2009-07-01

    Full Text Available Abstract Background Sesquiterpene lactones are characteristic metabolites of Asteraceae (or Compositae which often display potent bioactivities and are sequestered in specialized organs such as laticifers, resin ducts, and trichomes. For characterization of sunflower sesquiterpene synthases we employed a simple method to isolate pure trichomes from anther appendages which facilitated the identification of these genes and investigation of their enzymatic functions and expression patterns during trichome development. Results Glandular trichomes of sunflower (Helianthus annuus L. were isolated, and their RNA was extracted to investigate the initial steps of sesquiterpene lactone biosynthesis. Reverse transcription-PCR experiments led to the identification of three sesquiterpene synthases. By combination of in vitro and in vivo characterization of sesquiterpene synthase gene products in Escherichia coli and Saccharomyces cerevisiae, respectively, two enzymes were identified as germacrene A synthases, the key enzymes of sesquiterpene lactone biosynthesis. Due to the very low in vitro activity, the third enzyme was expressed in vivo in yeast as a thioredoxin-fusion protein for functional characterization. In in vivo assays, it was identified as a multiproduct enzyme with the volatile sesquiterpene hydrocarbon δ-cadinene as one of the two main products with α-muuorlene, β-caryophyllene, α-humulene and α-copaene as minor products. The second main compound remained unidentified. For expression studies, glandular trichomes from the anther appendages of sunflower florets were isolated in particular developmental stages from the pre- to the post-secretory phase. All three sesquiterpene synthases were solely upregulated during the biosynthetically active stages of the trichomes. Expression in different aerial plant parts coincided with occurrence and maturity of trichomes. Young roots with root hairs showed expression of the sesquiterpene synthase genes

  16. Wild Nicotiana Species as a Source of Cytoplasmic Male Sterility in Nicotianatabacum

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    Nikova V

    2014-12-01

    Full Text Available The results of our experiments executed to obtain tobacco male sterile lines through interspecific hybridization are summarized. Ten wild species from the genus Nicotiana: N. excelsior (exc, N. amplexicaulis (amp, N. rustica (rus, Nicotianaglauca (gla, N. velutina (vel, N. benthamiana (ben, N. maritima (mar, N. paniculata (pan, N. longiflora (lon and N. africana (afr were used as cytoplasmic donors and N. tabacum, cv. HarmanliiskaBasma (HB as a donor of the nucleus. Genetic effects of cytoplasmic-nuclear interaction of the studied species are discussed. Our results suggested that cytoplasmic male sterility (CMS was expressed when the cytoplasms of the above mentioned wild Nicotiana species were combined with the nucleus of N. tabacum. The 10 sources of CMS obtained in tobacco were characterized by altered flower phenotypes. Flowers are classified into types according the stamen, pistil and corolla modification. All these CMS sources were backcrossed to Oriental tobaccos, cvs. Tekne, Nevrokop B-12, Kroumovgrad 90 and Djebel 576, to develop corresponding CMS lines. The investigated cytoplasms produced compete male sterility in all those cultivars. The CMS lines preserved flower types, specific for every “sterile” cytoplasm. The extent of male organ modifications varied from apparently normal (but pollenless stamens in CMS (pan, (afr, some plants of (vel (mar through different degrees of malformations (shriveled anther on shortened filaments (lon, pinnate-like anthers on filaments of normal length (amp, petal - (ben, pistil- or stigma-like structures (rus, (gla to lack of male reproductive organs in (exc and in some plants of (vel, (mar, (rus and (gla. Most of the above mentioned cytoplasms had normal female gametophyte and good seed productivity. Alterations of the pistils were observed in CMS (rus, (exc and (ben causing reduction of the seed set. Electrophoresis of seed proteins of the tobacco cultivars and their CMS lines also suggested that

  17. Flower morpho-anatomy in Epiphyllum phyllanthus (Cactaceae Morfo-anatomía de la flor de Epiphyllum phyllanthus (Cactaceae

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    Odair José Garcia de Almeida

    2010-04-01

    Full Text Available The aim of this contribution was to analyze the morpho-anatomical floral structure of Epiphyllum phyllanthus (L. Haw., a widely distributed species across South America, occurring in humid forests as an epiphyte. Flowers and flower buds were collected in Maringá, Paraná State, Brazil, fixed, processed, and analyzed under light microscope and scanning electron microscope. The flower is sessile and epigynous with a well-developed hypanthium. All flower whorls have uniseriate epidermis. Secretory cavities containing mucilage and calcium oxalate crystals occur throughout the floral parenchymatous tissue. The androecium has many stamens with tetrasporangiate and bithecal anthers. The wall of the young anther is formed by epidermis, endothecium, a middle layer, and binucleate secretory tapetum that eventually becomes uninucleate. The gynoecium is syncarpous with 9-10 carpels, pluriovulate, and with parietal placentation. The ovary has inverted vascular bundles in a similar pattern as in Pereskia. The nectariferous region occurs on the inner surface of the hypanthium. The stigma has 9-10 lobes with a secretory epidermis. The ovules are circinotropous, bitegmic, crassinucelate, and have long funiculus as in many other Cactaceae.El objetivo de esta investigación fue analizar la morfo-anatomía de la flor de Epiphyllum phyllanthus (L. Haw, especie con distribución amplia en los bosques húmedos de América del Sur como epífita. Se recolectaron flores y botones en Maringá, PR, Brasil, fijados, procesados y analizados con microscopio de luz y con microscopio electrónico de barrido. La flor es sésil, epígina con hipanto desarrollado. Todos los verticilos florales presentan epidermis simple. Cavidades secretoras con mucilago y cristales de oxalato de calcio se encuentran en todo el tejido parenquimático de la flor. El androceo posee muchos estambres, con anteras bitecas y tetraesporangiadas. La pared de la antera joven está formada por epidermis

  18. Expression of kenaf mitochondrial chimeric genes HM184 causes male sterility in transgenic tobacco plants.

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    Zhao, Yanhong; Liao, Xiaofang; Huang, Zhipeng; Chen, Peng; Zhou, Bujin; Liu, Dongmei; Kong, Xiangjun; Zhou, Ruiyang

    2015-08-01

    Chimeric genes resulting from the rearrangement of a mitochondrial genome were generally thought to be a causal factor in the occurrence of cytoplasmic male sterility (CMS). In the study, earlier we reported that identifying a 47 bp deletion at 3'- flanking of atp9 that was linked to male sterile cytoplasm in kenaf. The truncated fragment was fused with atp9, a mitochondrial transit signal (MTS) and/or GFP, comprised two chimeric genes MTS-HM184-GFP and MTS-HM184. The plant expression vector pBI121 containing chimeric genes were then introduced to tobacco plants by Agrobacterium-mediated T-DNA transformation. The result showed that certain transgenic plants were male sterility or semi-sterility, while some were not. The expression analysis further demonstrated that higher level of expression were showed in the sterility plants, while no expression or less expression in fertility plants, the levels of expression of semi-sterility were in between. And the sterile plant (containing MTS-HM184-GFP) had abnormal anther produced malformed/shriveled pollen grains stained negative that failed to germinate (0%), the corresponding fruits was shrunken, the semi-sterile plants having normal anther shape produced about 10-50% normal pollen grains, the corresponding fruits were not full, and the germination rate was 58%. Meanwhile these transgenic plants which altered on fertility were further analyzed in phenotype. As a result, the metamorphosis leaves were observed in the seedling stage, the plant height of transgenic plants was shorter than wild type. The growth duration of transgenic tobacco was delayed 30-45 days compared to the wild type. The copy numbers of target genes of transgenic tobacco were analyzed using the real-time quantitative method. The results showed that these transgenic plants targeting-expression in mitochondrial containing MTS-HM184-GFP had 1 copy and 2 copies, the other two plants containing MTS-HM184 both had 3 copies, but 0 copy in wild type. In

  19. Regulation of anthocyanin biosynthesis in peach fruits.

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    Rahim, Md Abdur; Busatto, Nicola; Trainotti, Livio

    2014-11-01

    MYB10.1 and MYB10.3, with bHLH3, are the likely regulators of anthocyanin biosynthesis in peach fruit. MYB10.1/2/3 forms a cluster on the same genomic fragment where the Anther color ( Ag ) trait is located. Anthocyanins are bioactive compounds responsible for the pigmentation of many plant parts such as leaves, flowers, fruits and roots, and have potential benefits to human health. In peach [Prunus persica (L.) Batsch], peel color is a key determinant for fruit quality and is regulated by flavonoids including anthocyanins. The R2R3 MYB transcription factors (TFs) control the expression of anthocyanin biosynthetic genes with the help of co-activators belonging to the basic-helix-loop-helix (bHLH) and WD40 repeat families. In the peach genome six MYB10-like and three bHLH-like TFs were identified as candidates to be the regulators of the anthocyanin accumulation, which, in yellow flesh fruits, is highest in the peel, abundant in the part of the mesocarp surrounding the stone and lowest in the mesocarp. The expression of MYB10.1 and MYB10.3 correlates with anthocyanin levels of different peach parts. They also have positive correlation with the expression of key structural genes of the anthocyanin pathway, such as CHS, F3H, and UFGT. Functions of peach MYB10s were tested in tobacco and shown to activate key genes in the anthocyanin pathway when bHLHs were co-expressed as partners. Overexpression of MYB10.1/bHLH3 and MYB10.3/bHLH3 activated anthocyanin production by up-regulating NtCHS, NtDFR and NtUFGT while other combinations were not, or much less, effective. As three MYB10 genes are localized in a genomic region where the Ag trait, responsible for anther pigmentation, is localized, it is proposed they are key determinant to introduce new peach cultivars with higher antioxidant level and pigmented fruit.

  20. Biologia reprodutiva de Psychotria poeppigiana Mull. Arg. (Rubiaceae em mata de galeria Reproductive biology of Psychotria poeppigiana Mull. Arg. (Rubiaceae in gallery forest

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    Christiano Peres Coelho

    2004-09-01

    Full Text Available Psychotria L. (Rubiaceae é o gênero com mais espécies heterostílicas dentre as Angiospermas. O objetivo deste trabalho é descrever a biologia floral, fenologia, o sistema reprodutivo e os polinizadores de Psychotria poeppigiana Müll. Arg. As inflorescências são capitadas terminais, com brácteas vermelhas e flores amarelas apresentando dois morfos distintos: brevistiladas e longistiladas, caracterizadas por flores hermafroditas com diferentes comprimentos de estiletes e posicionamento oposto das anteras (hercogamia recíproca. Encontrou-se diferenças no tamanho das anteras, dos grãos de pólen e da superfície estigmática entre os morfotipos. Polinizações controladas mostraram que os morfotipos apresentam auto-incompatibilidade e intramorfo-incompatibilidade ao nível do estigma e do estilete. Os visitantes são pequenas vespas, abelhas, borboletas e beija-flores, que visitam as flores com maior freqüência no início da manhã. De acordo com a freqüência e eficiência no comportamento de transportar os grãos de pólen entre os morfos florais, o principal polinizador foi o beija-flor Thalurania furcata. O néctar é produzido em pequena quantidade (máximo de 8µl e durante a abertura das flores, que ocorre entre 5 e 7h. A espécie forma agrupamentos devido à existência de reprodução vegetativa.Psychotria L. (Rubiaceae is the genus with the most heterostylous species in the angiosperms. The objective of this study is to describe floral biology, phenology, reproductive system, and pollinators of Psychotria poeppigiana Müll. Arg. The terminal inflorescences are capitate with red bracts and yellow flowers, and presented two different morphs: pin and thrum, characterized by hermaphroditic flowers with different lengths of styles and opposed position of the anthers (reciprocal herkogamy. Dimorphism was also observed in the size of anthers, pollen grains and stigmatic surfaces. Controlled pollination revealed self

  1. Reproductive biology of Bowdichia virgilioides Kunth (Fabaceae - doi: 10.4025/actascibiolsci.v33i4.9003 Reproductive biology of Bowdichia virgilioides Kunth (Fabaceae - doi: 10.4025/actascibiolsci.v33i4.9003

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    Samyra Ramos Chaves

    2011-09-01

    Full Text Available The aim of this study was to investigate the reproductive biology of Bowdichia virgilioides in an area of Cerrado (Brazilian Savanna. The study was carried out in Chapadinha, State of Maranhão in northeastern Brazil. Bowdichia virgilioides has cornucopia flowering and annual pattern. Flowering occurred at the beginning of the dry season, between June and August; and fruiting in the middle of this season, between July and October. The anthesis of B. virgilioides is diurnal, and the main flower resource is the nectar. During the flower opening, the anthers becomes dehiscent and thus pollen grains are deposited at the stigma, promoting automatic self-pollination. The species is self-compatible and apomitic. In the study area, they were visited by nine species of bees, four butterflies, two wasps, and two hummingbirds. The visits began in early morning and persisted throughout the day, with a peak of activity between 8:00 and 9:00 hours. Species of Centris were the main visitors of B. virgilioides. The butterfly and wasp species were considered resource robbers, and other floral visitors were considered occasional visitors. Although the flowers of B. virgilioides are widely visited, the species shows a high rate of inbreeding because of automatic self-pollination.The aim of this study was to investigate the reproductive biology of Bowdichia virgilioides in an area of Cerrado (Brazilian Savanna. The study was carried out in Chapadinha, State of Maranhão in northeastern Brazil. Bowdichia virgilioides has cornucopia flowering and annual pattern. Flowering occurred at the beginning of the dry season, between June and August; and fruiting in the middle of this season, between July and October. The anthesis of B. virgilioides is diurnal, and the main flower resource is the nectar. During the flower opening, the anthers becomes dehiscent and thus pollen grains are deposited at the stigma, promoting automatic self-pollination. The species is self

  2. A rat pancreatic ribonuclease fused to a late cotton pollen promoter severely reduces pollen viability in tobacco plants

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    R.B. Bernd-Souza

    2000-06-01

    Full Text Available The effects of an animal RNase fused to the late cotton pollen-specific promoter G9 in a plant system were investigated. Expression of the chimeric genes G9-uidA and G9-RNase in tobacco plants showed that the 1.2-kb promoter fragment of the G9 gene was sufficient to maintain tissue and temporal specificity in a heterologous system. GUS (beta-glucuronidase expression was detected only in pollen from anther stage 6 through anthesis, with maximal GUS activity in pollen from stage 10 anthers. Investigating the effects of the rat RNase on pollen viability at stage 10, we found that pollen viability was reduced from 79 to 8% and from 89 to 40%, in pollen germination and fluoresceine diacetate assays, respectively, in one G9-RNase transgenic line, suggesting a lethal effect of the RNase gene. This indicates that the rat RNase produces deleterious effects in this plant system and may be useful for engineering male sterility.Foram investigados os efeitos da expressão de uma ribonuclease de origem animal em um sistema vegetal, ligando-se esta ao promotor do gene pólen-específico G9 de algodão. Examinou-se a expressão dos genes quiméricos G9-uidA e G9-RNase em plantas de tabaco e determinou-se que o fragmento de 1.2 kb do promotor do gene G9 foi suficiente para manter a especificidade temporal e espacial da expressão, em sistema heterólogo. A expressão do gene GUS foi detectada somente em pólen, do estágio 6 do desenvolvimento da antera até a antese, com atividade máxima em pólen de anteras no estágio 10. Estudos neste estágio com linhagens transgênicas contendo G9-RNase mostraram que um clone transgênico apresentava reduções na viabilidade do pólen de 79 para 8% e de 89 para 40% nos testes de germinação e coloração com diacetato de fluoresceína, respectivamente, sugerindo letalidade na expressão do gene de RNase. Estes resultados indicam que a RNase animal apresenta um efeito deletério em planta e oferece possibilidade de uso

  3. TGMS in Rapeseed (Brassica napus Resulted in Aberrant Transcriptional Regulation, Asynchronous Microsporocyte Meiosis, Defective Tapetum, and Fused Sexine

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    Xi-Qiong Liu

    2017-07-01

    Full Text Available The thermo-sensitive genic male sterility (TGMS line SP2S is a spontaneous rapeseed mutation with several traits that are favorable for the production of two-line hybrids. To uncover the key cellular events and genetic regulation associated with TGMS expression, a combined study using cytological observation, transcriptome profiling, and gene expression analysis was conducted for SP2S and its near-isogenic line SP2F grown under warm conditions. Asynchronous microsporocyte meiosis and abnormal tapetal plastids and elaioplasts were demonstrated in the anther of SP2S. The tetrad microspore did not undergo mitosis before the cytoplasm degenerated. Delayed degradation of the tetrad wall, which led to tetrad microspore aggregation, resulted in postponement of sexine (outer layer of pollen exine formation and sexine fusion in the tetrad. The nexine (foot layer of exine was also absent. The delay of tetrad wall degradation and abnormality of the exine structure suggested that the defective tapetum lost important functions. Based on transcriptomic comparisons between young flower buds of SP2S and SP2F plants, a total of 465 differentially expressed transcripts (DETs were identified, including 303 up-regulated DETs and 162 down-regulated DETs in SP2S. Several genes encoding small RNA degrading nuclease 2, small RNA 2′-O-methyltransferase, thioredoxin reductase 2, regulatory subunit A alpha isoform of serine/threonine-protein phosphatase 2A, glycine rich protein 1A, transcription factor bHLH25, leucine-rich repeat receptor kinase At3g14840 like, and fasciclin-like arabinogalactan proteins FLA19 and FLA20 were greatly depressed in SP2S. Interestingly, a POLLENLESS3-LIKE 2 gene encoding the Arabidopsis MS5 homologous protein, which is necessary for microsporocyte meiosis, was down-regulated in SP2S. Other genes that were up-regulated in SP2S encoded glucanase A6, ethylene-responsive transcription factor 1A-like, pollen-specific SF3, stress

  4. OsORC3 is required for lateral root development in rice.

    Science.gov (United States)

    Chen, Xinai; Shi, Jing; Hao, Xi; Liu, Huili; Shi, Jianghua; Wu, Yunrong; Wu, Zhongchang; Chen, Mingxiu; Wu, Ping; Mao, Chuanzao

    2013-04-01

    The origin recognition complex (ORC) is a pivotal element in DNA replication, heterochromatin assembly, checkpoint regulation and chromosome assembly. Although the functions of the ORC have been determined in yeast and model animals, they remain largely unknown in the plant kingdom. In this study, Oryza sativa Origin Recognition Complex subunit 3 (OsORC3) was cloned using map-based cloning procedures, and functionally characterized using a rice (Oryza sativa) orc3 mutant. The mutant showed a temperature-dependent defect in lateral root (LR) development. Map-based cloning showed that a G→A mutation in the 9th exon of OsORC3 was responsible for the mutant phenotype. OsORC3 was strongly expressed in regions of active cell proliferation, including the primary root tip, stem base, lateral root primordium, emerged lateral root primordium, lateral root tip, young shoot, anther and ovary. OsORC3 knockdown plants lacked lateral roots and had a dwarf phenotype. The root meristematic zone of ORC3 knockdown plants exhibited increased cell death and reduced vital activity compared to the wild-type. CYCB1;1::GUS activity and methylene blue staining showed that lateral root primordia initiated normally in the orc3 mutant, but stopped growing before formation of the stele and ground tissue. Our results indicate that OsORC3 plays a crucial role in the emergence of lateral root primordia. © 2013 The Authors The Plant Journal © 2013 Blackwell Publishing Ltd.

  5. Pollen development in Annona cherimola Mill. (Annonaceae. Implications for the evolution of aggregated pollen

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    Hormaza Jose I

    2009-10-01

    Full Text Available Abstract Background In most flowering plants, pollen is dispersed as monads. However, aggregated pollen shedding in groups of four or more pollen grains has arisen independently several times during angiosperm evolution. The reasons behind this phenomenon are largely unknown. In this study, we followed pollen development in Annona cherimola, a basal angiosperm species that releases pollen in groups of four, to investigate how pollen ontogeny may explain the rise and establishment of this character. We followed pollen development using immunolocalization and cytochemical characterization of changes occurring from anther differentiation to pollen dehiscence. Results Our results show that, following tetrad formation, a delay in the dissolution of the pollen mother cell wall and tapetal chamber is a key event that holds the four microspores together in a confined tapetal chamber, allowing them to rotate and then bind through the aperture sites through small pectin bridges, followed by joint sporopollenin deposition. Conclusion Pollen grouping could be the result of relatively minor ontogenetic changes beneficial for pollen transfer or/and protection from desiccation. Comparison of these events with those recorded in the recent pollen developmental mutants in Arabidopsis indicates that several failures during tetrad dissolution may convert to a common recurring phenotype that has evolved independently several times, whenever this grouping conferred advantages for pollen transfer.

  6. An effective approach for identification of in vivo protein-DNA binding sites from paired-end ChIP-Seq data

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    Wilson Zoe A

    2010-02-01

    Full Text Available Abstract Background ChIP-Seq, which combines chromatin immunoprecipitation (ChIP with high-throughput massively parallel sequencing, is increasingly being used for identification of protein-DNA interactions in vivo in the genome. However, to maximize the effectiveness of data analysis of such sequences requires the development of new algorithms that are able to accurately predict DNA-protein binding sites. Results Here, we present SIPeS (Site Identification from Paired-end Sequencing, a novel algorithm for precise identification of binding sites from short reads generated by paired-end solexa ChIP-Seq technology. In this paper we used ChIP-Seq data from the Arabidopsis basic helix-loop-helix transcription factor ABORTED MICROSPORES (AMS, which is expressed within the anther during pollen development, the results show that SIPeS has better resolution for binding site identification compared to two existing ChIP-Seq peak detection algorithms, Cisgenome and MACS. Conclusions When compared to Cisgenome and MACS, SIPeS shows better resolution for binding site discovery. Moreover, SIPeS is designed to calculate the mappable genome length accurately with the fragment length based on the paired-end reads. Dynamic baselines are also employed to effectively discriminate closely adjacent binding sites, for effective binding sites discovery, which is of particular value when working with high-density genomes.

  7. Use of repellents for honeybees (Apis mellifera L. in vitro in the yellow passion-fruit (Passiflora edulis Deg crop and in confined beef cattle feeders

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    D. Nicodemo

    2004-01-01

    Full Text Available The presence of Apis mellifera in places such as candy and soft drink factories, restaurants, and ice-cream shops has been a concern to many people. In the yellow passion-fruit crop, Apis mellifera is able to collect all anther pollen but has no active role in pollination. Honeybees also visit animal feeders with chopped sugar cane, preventing the cattle from eating. This work studied the effect of natural and synthetic substances as Apis mellifera repellents in vitro in the yellow passion-fruit crop and in confined beef cattle feeders. There was a repellent effect in vitro with the following substances in decreasing order: tobacco, rue, garlic, parsley, and century plant extracts; average effect was twenty-five minutes. For the yellow passion-fruit, garlic extracts and 2-heptanone were equally efficient with a two and a half hour repellent action. Garlic and citronella extracts were efficient in repelling Apis mellifera from confined beef cattle feeder for six hours. Garlic repellent action was higher than citronella.

  8. Direct Gene Transfer into Plant Mature Seeds via Electroporation After Vacuum Treatment

    Science.gov (United States)

    Hagio, Takashi

    A number of direct gene transfer methods have been used successfully in plant genetic engineering, providing powerful tools to investigate fundamental and applied problems in plant biology (Chowrira et al., 1996; D'halluin et al., 1992; Morandini and Salamini, 2003; Rakoczy-Trojanowska, 2002; Songstad et al., 1995). In cereals, several methods have been found to be suitable for obtaining transgenic plant; these include bombardment of scutellum (Hagio et al., 1995) and inflorescence cultures (He et al., 2001), and silicon carbide fiber-mediated DNA delivery (Asano et al., 1991) and Agrobacterium tumefaciens transformation (Potrykus, 1990). Electroporation of cereal protoplasts also has proved successful but it involves prolonged cell treatments and generally is limited by the difficulties of regeneration from cereal protoplast cultures (Fromm et al., 1987). Many laboratories worldwide are now using Agrobacterium as a vehicle for routine production of transgenic crop plants. The primary application of the particle system (Klein et al., 1987) has been for transformation of species recalcitrant to conventional Agrobacterium (Binns, 1990) or protoplast methods. But these conventional methods can be applied to the species and varieties that are amenable to tissue culture (Machii et al., 1998). Mature seeds are readily available and free from the seasonal limits that immature embryo, inflorescence, and anther have. This method enables us to produce transgenic plants without time-consuming tissue culture process.

  9. Revision of theLimaclade (Miconia sect. Lima, Miconieae, Melastomataceae) of the Greater Antilles.

    Science.gov (United States)

    Majure, Lucas C; Bécquer, Eldis R; Judd, Walter S

    2016-01-01

    Miconia sect. Lima is an entirely Greater Antillean clade that consists of 19 known species of shrubs and small trees, which were previously recognized under the polyphyletic genera Leandra and Ossaea . The highest species richness in the clade is represented on Cuba (10 species), followed by Hispaniola (8 species) and then Jamaica (1 species). Here we present a taxonomic revision of the clade based on the study of species in the field, herbarium specimens, as well as a DNA-based phylogeny reconstruction. The Lima clade most likely originated on Cuba and then spread to Jamaica once and Hispaniola multiple times. Species of this clade can be recognized by the well developed bulla-based hairs of the adaxial leaf surface, as well as the clavate-dendritic hairs produced along the primary, secondary and tertiary veins of the adaxial leaf surface, mostly towards the leaf base, terminal inflorescences, acute petal apices, slightly bulla-based hairs produced subapically along the petal abaxial surface, and anthers with a dorso-basal appendage and a single, dorsally oriented pore. Descriptions, synonymies, along with distribution maps and illustrations/figures, are given for each species. Miconia pagnolensis sp. nov. is newly described in this revision.

  10. Identification of Proteins Involved in Carbohydrate Metabolism and Energy Metabolism Pathways and Their Regulation of Cytoplasmic Male Sterility in Wheat

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    Xingxia Geng

    2018-01-01

    Full Text Available Cytoplasmic male sterility (CMS where no functional pollen is produced has important roles in wheat breeding. The anther is a unique organ for male gametogenesis and its abnormal development can cause male sterility. However, the mechanisms and regulatory networks related to plant male sterility are poorly understood. In this study, we conducted comparative analyses using isobaric tags for relative and absolute quantification (iTRAQ of the pollen proteins in a CMS line and its wheat maintainer. Differentially abundant proteins (DAPs were analyzed based on Gene Ontology classifications, metabolic pathways and transcriptional regulation networks using Blast2GO. We identified 5570 proteins based on 23,277 peptides, which matched with 73,688 spectra, including proteins in key pathways such as glyceraldehyde-3-phosphate dehydrogenase, pyruvate kinase and 6-phosphofructokinase 1 in the glycolysis pathway, isocitrate dehydrogenase and citrate synthase in the tricarboxylic acid cycle and nicotinamide adenine dinucleotide (NADH-dehydrogenase and adenosine-triphosphate (ATP synthases in the oxidative phosphorylation pathway. These proteins may comprise a network that regulates male sterility in wheat. Quantitative real time polymerase chain reaction (qRT-PCR analysis, ATP assays and total sugar assays validated the iTRAQ results. These DAPs could be associated with abnormal pollen grain formation and male sterility. Our findings provide insights into the molecular mechanism related to male sterility in wheat.

  11. Identification of Genes Potentially Associated with the Fertility Instability of S-Type Cytoplasmic Male Sterility in Maize via Bulked Segregant RNA-Seq.

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    Aiguo Su

    Full Text Available S-type cytoplasmic male sterility (CMS-S is the largest group among the three major types of CMS in maize. CMS-S exhibits fertility instability as a partial fertility restoration in a specific nuclear genetic background, which impedes its commercial application in hybrid breeding programs. The fertility instability phenomenon of CMS-S is controlled by several minor quantitative trait locus (QTLs, but not the major nuclear fertility restorer (Rf3. However, the gene mapping of these minor QTLs and the molecular mechanism of the genetic modifications are still unclear. Using completely sterile and partially rescued plants of fertility instable line (FIL-B, we performed bulk segregant RNA-Seq and identified six potential associated genes in minor effect QTLs contributing to fertility instability. Analyses demonstrate that these potential associated genes may be involved in biological processes, such as floral organ differentiation and development regulation, energy metabolism and carbohydrates biosynthesis, which results in a partial anther exsertion and pollen fertility restoration in the partially rescued plants. The single nucleotide polymorphisms (SNPs identified in two potential associated genes were validated to be related to the fertility restoration phenotype by KASP marker assays. This novel knowledge contributes to the understanding of the molecular mechanism of the partial fertility restoration of CMS-S in maize and thus helps to guide the breeding programs.

  12. Recombination Events Involving the atp9 Gene Are Associated with Male Sterility of CMS PET2 in Sunflower

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    Antje Reddemann

    2018-03-01

    Full Text Available Cytoplasmic male sterility (CMS systems represent ideal mutants to study the role of mitochondria in pollen development. In sunflower, CMS PET2 also has the potential to become an alternative CMS source for commercial sunflower hybrid breeding. CMS PET2 originates from an interspecific cross of H. petiolaris and H. annuus as CMS PET1, but results in a different CMS mechanism. Southern analyses revealed differences for atp6, atp9 and cob between CMS PET2, CMS PET1 and the male-fertile line HA89. A second identical copy of atp6 was present on an additional CMS PET2-specific fragment. In addition, the atp9 gene was duplicated. However, this duplication was followed by an insertion of 271 bp of unknown origin in the 5′ coding region of the atp9 gene in CMS PET2, which led to the creation of two unique open reading frames orf288 and orf231. The first 53 bp of orf288 are identical to the 5′ end of atp9. Orf231 consists apart from the first 3 bp, being part of the 271-bp-insertion, of the last 228 bp of atp9. These CMS PET2-specific orfs are co-transcribed. All 11 editing sites of the atp9 gene present in orf231 are fully edited. The anther-specific reduction of the co-transcript in fertility-restored hybrids supports the involvement in male-sterility based on CMS PET2.

  13. An updated checklist and key to the open-panicled species of Poa L. (Poaceae) in Peru including three new species, Poa ramoniana, Poa tayacajaensis, and Poa urubambensis

    Science.gov (United States)

    Sylvester, Steven P.; Soreng, Robert J.; Peterson, Paul M.; Sylvester, Mitsy D.P.V.

    2016-01-01

    Abstract We provide an updated checklist and key to the 30 Poa species with open panicles from Peru which includes previously circumscribed Dissanthelium and Aphanelytrum species, new taxon records, and three undescribed species. Poa compressa, Poa grisebachii, and Poa leioclada are recorded from Peru for the first time. A number of species are placed in synonymy: Poa carazensis, Poa ferreyrae and Poa tovarii are synonymized under the name Poa fibrifera; Poa adusta (tentatively) and Poa pilgeri are synonymized under Poa candamoana; Poa superata is synonymized under Poa grisebachii; and Poa paramoensis is synonymized under Poa huancavelicae. Included within this treatment are three new species, Poa ramoniana, Poa tayacajaensis and Poa urubambensis, which are described and illustrated. Poa ramoniana, found growing near lakes in high elevation Puna grasslands of Junín, is similar to a small form of Poa glaberrima, but differs in having rhizomes and growing to only 5 cm tall. Poa tayacajaensis, found from shrublands on Andean slopes of Huancavelica and Huánuco, bears similarities to Poa aequatoriensis but differs in having shorter lemmas which are pubescent between the veins, densely scabrous sheaths with smooth, glabrous throats, and shorter ligules. Poa urubambensis, a common element of the undisturbed Polylepis forest understory of the Cordillera Urubamba, Cusco, is distinct from all other members of open-panicled Poa’s by having glabrous lemmas with a smooth and glabrous callus, and notably small anthers. The type material for the name Poa adusta is discussed and a lectotype is selected. PMID:27489489

  14. Two new non-spiny Solanum (Solanaceae from the Gran Chaco Americano and a key for the herbaceous glandular-pubescent solanums from the region

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    Tiina Sarkinen

    2016-11-01

    Full Text Available The Gran Chaco Americano is a major savanna woodland system in South America that harbours great plant and animal diversity. Two new herbaceous species of the Morelloid clade of Solanum (largely corresponding to the traditional Solanum section Solanum are described here from the Bolivian Chaco. Both species are morphologically similar to a group of related species with glandular pubescence and enlarged, foliaceous calyces that includes S. atriplicifolium Gillies ex Nees, S. nitidibaccatum Bitter, S. physalifolium Rusby, S. sarrachoides Sendtn. and S. tweedianum Hook. Solanum woodii Särkinen & S.Knapp, sp. nov. is unusual in the Morelloid clade in having tapering anthers on short filaments, and is superficially similar to the unrelated S. anomalostemon S.Knapp & M.Nee from dry forests in Peru. Solanum michaelis Särkinen & S.Knapp, sp. nov. is distinct in its enlarged calyx with a short tube and long lobes that apparently reflex at fruit maturity. Both new taxa are illustrated, their conservation status assessed, and their distributions mapped. We also provide a key to the glandular-pubescent herbaceous Solanum species of the Chaco vegetation to aid in identification of these taxa.

  15. Aechmea pectinata: a hummingbird-dependent bromeliad with inconspicuous flowers from the rainforest in south-eastern Brazil.

    Science.gov (United States)

    Canela, Maria Bernadete Ferreira; Sazima, Marlies

    2003-11-01

    The pollination biology of Aechmea pectinata (Bromeliaceae) was studied in a submontane rainforest in south-eastern Brazil. This species has a mainly clumped distribution and its aggregated individuals are likely to be clones. From October to January, during the flowering period, the distal third of its leaves becomes red. The inflorescence produces 1-15 flowers per day over a period of 20-25 d. The flowers are inconspicuous, greenish-white coloured, tubular shaped with a narrow opening, and the stigma is situated just above the anthers. Anthesis begins at 0400 h and flowers last for about 13 h. The highest nectar volume and sugar concentration occur between 0600 and 1000 h, and decrease throughout the day. Aechmea pectinata is self-incompatible and therefore pollinator-dependent. Hummingbirds are its main pollinators (about 90 % of the visits), visiting flowers mainly in the morning. There is a positive correlation between the number of hummingbird visits per inflorescence and the production of nectar, suggesting that the availability of this resource is important in attracting and maintaining visitors. The arrangement of the floral structures favours pollen deposition on the bill of the hummingbirds. Flowers in clumps promote hummingbird territoriality, and a consequence is self-pollination in a broader sense (geitonogamy) as individuals in assemblages are genetically close. However, trap-lining and intruding hummingbirds promote cross-pollination. These observations suggest that successful fruit set of A. pectinata depends on both the spatial distribution of its individuals and the interactions among hummingbirds.

  16. Pollen development in Annona cherimola Mill. (Annonaceae). Implications for the evolution of aggregated pollen

    Science.gov (United States)

    Lora, Jorge; Testillano, Pilar S; Risueño, Maria C; Hormaza, Jose I; Herrero, Maria

    2009-01-01

    Background In most flowering plants, pollen is dispersed as monads. However, aggregated pollen shedding in groups of four or more pollen grains has arisen independently several times during angiosperm evolution. The reasons behind this phenomenon are largely unknown. In this study, we followed pollen development in Annona cherimola, a basal angiosperm species that releases pollen in groups of four, to investigate how pollen ontogeny may explain the rise and establishment of this character. We followed pollen development using immunolocalization and cytochemical characterization of changes occurring from anther differentiation to pollen dehiscence. Results Our results show that, following tetrad formation, a delay in the dissolution of the pollen mother cell wall and tapetal chamber is a key event that holds the four microspores together in a confined tapetal chamber, allowing them to rotate and then bind through the aperture sites through small pectin bridges, followed by joint sporopollenin deposition. Conclusion Pollen grouping could be the result of relatively minor ontogenetic changes beneficial for pollen transfer or/and protection from desiccation. Comparison of these events with those recorded in the recent pollen developmental mutants in Arabidopsis indicates that several failures during tetrad dissolution may convert to a common recurring phenotype that has evolved independently several times, whenever this grouping conferred advantages for pollen transfer. PMID:19874617

  17. Scalar multi-wormholes

    International Nuclear Information System (INIS)

    Egorov, A I; Kashargin, P E; Sushkov, Sergey V

    2016-01-01

    In 1921 Bach and Weyl derived the method of superposition to construct new axially symmetric vacuum solutions of general relativity. In this paper we extend the Bach–Weyl approach to non-vacuum configurations with massless scalar fields. Considering a phantom scalar field with the negative kinetic energy, we construct a multi-wormhole solution describing an axially symmetric superposition of N wormholes. The solution found is static, everywhere regular and has no event horizons. These features drastically tell the multi-wormhole configuration from other axially symmetric vacuum solutions which inevitably contain gravitationally inert singular structures, such as ‘struts’ and ‘membranes’, that keep the two bodies apart making a stable configuration. However, the multi-wormholes are static without any singular struts. Instead, the stationarity of the multi-wormhole configuration is provided by the phantom scalar field with the negative kinetic energy. Anther unusual property is that the multi-wormhole spacetime has a complicated topological structure. Namely, in the spacetime there exist 2 N asymptotically flat regions connected by throats. (paper)

  18. Gamma ray induced male sterility mutant in lentil

    International Nuclear Information System (INIS)

    Srivastava, A.; Yadav, A.K.

    2001-01-01

    Full text: Male sterility refers to the failure of pollen grains to bring about effective fertilization, either due to structural default or physiological disfunctioning and has special significance in hybridization programmes. Male steriles have been produced in a number of crop plants like red gram, pigeon pea, mung bean, khesari and lentil. A completely male sterile mutant was isolated in Lens culinaris Medik, after seed treatment with 100 Gy dose of gamma rays. The male sterile mutant showed 100% pollen sterility but was morphologically more vigorous than the parent plants. It showed more branches and its leaves were bigger, more oblong and dark green. The number of flowers borne by the mutant was significantly higher than any other plant of the treatment. The size of the flowers was also increased but the anthers were smaller in size. Pollen grains were few in number, round in shape but empty and did not take up any stain, indicating that normal microsporogenesis had not taken place. This male sterile mutant was used as the female parent and pollinated with pollen of a parent. Four pods with one seed in each were formed indicating that the mutant was female fertile. The seeds were smaller than those of the parent variety and also dark coloured. The mutant showed increased vigour and flower number as compared to parental plants. Lentil is an important pulse crop and induction of variability in its germplasm is necessary for its improvement. Male steriles can be used conveniently in lentil hybridization programmes. (author)

  19. Morphological, Micoscopical Studies and Elemental analysis of Polygonum Chinese L. and Rhoeo discolor Hance

    International Nuclear Information System (INIS)

    Moe Moe Lwin

    2008-03-01

    In the present study, two selected medicinal plants, namely Polygonum chinense L. (Mahaga-Kyansit) and Rhoeo discolor Hance. (Mi-gwin-gamon) are collected from Dawei District. In this paper, the outstanding features of selected plants, microscopical characters and elemental analysis of these leaves are also presented.In morphological studies of Mahaga-kyansit, herbs, swollen at nodes, black-coloured patches present at central portion of leaf blade, ochreate stipules. The inflorescences are terminally corymbose. The ovary trigonous-ovoid, stigma trifixed. In microscopical studies, stomata anomocytic. The cuticle is striation on both surface. In transverse section of midrib, the vascular bundles are collateral, about 8-10 numbers in basal, one was larger than the other bundles, 2numbers in middle regions and 1 bundle in apical regions. Calcium oxalate crystals (Rosette) are present in the parenchymatous cells. In the present study, the Migwin-gamon are rosette-forming succulent herbs. The leaves are crowded, upright, the upper surface green, the lower surface rich reddish-purple. The inflorescences are axillary, boat-shaped. Flowers involucres bracts. The androecium are stamens 6, often clothed wIth moniliform hairs, anthers often with and expanded or variously modified connective. The gynaecium are carpel 3,, trilocular, stigma capitate. In the microscopical studies, the leaves are isobilateral leaf. The stomata are tetracytic type. Lower epidermis cells larger than the upper one and stoma in the lower epidermis. Crystal of tetragonal system form (Prism) present in the mesophyll cells.

  20. Spatio Temporal Expression Pattern of an Insecticidal Gene (cry2A in Transgenic Cotton Lines

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    Allah BAKHSH

    2012-11-01

    Full Text Available The production of transgenic plants with stable, high-level transgene expression is important for the success of crop improvement programs based on genetic engineering. The present study was conducted to evaluate genomic integration and spatio temporal expression of an insecticidal gene (cry2A in pre-existing transgenic lines of cotton. Genomic integration of cry2A was evaluated using various molecular approaches. The expression levels of cry2A were determined at vegetative and reproductive stages of cotton at regular intervals. These lines showed a stable integration of insecticidal gene in advance lines of transgenic cotton whereas gene expression was found variable with at various growth stages as well as in different plant parts throughout the season. The leaves of transgenic cotton were found to have maximum expression of cry2A gene followed by squares, bolls, anthers and petals. The protein level in fruiting part was less as compared to other parts showing inconsistency in gene expression. It was concluded that for culturing of transgenic crops, strategies should be developed to ensure the foreign genes expression efficient, consistent and in a predictable manner.

  1. The morphology of pollen presenter and polymorphism of pollen grains Taraxacum officinale F. H. Wigg.

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    Elżbieta Weryszko-Chmielewska

    2012-12-01

    Full Text Available The study of the structure of the pollen presenter of Taraxacum officinale and morphology of pollen grains was conducted based on plant material sampled from three different sites. One of them was a forest meadow situated away from the city, and the other two were located in the city centre of Lublin. Light and electron scanning microscopy were used in the study. The pollen presenter in Taraxacum officinale occurs at the upper part of the style situated over the androecium and on the outer part of the stigma. Numerous unicellular trichomes are found on the entire surface of the epidermis of the presenter. The function of the presenter consists in transferring pollen grains above the androecium and corolla petals. Its activity does not stop after pollen release from anthers. Taraxacum pollen grains represent the Crepis - type. Most frequently, they are tricolporate, radially symmetric and isopolar. In terms of the size, they are included in medium-sized grains. In the material examined, many deformed and asymmetric grains were observed, though they were marked by high viability at the level of 96.5-99%. Grains with the largest average lengths of the equatorial and polar axes were found in plants sampled from the meadow situated out of town. In the plant material from all sites, grains with disturbances of the external structure occurred.

  2. CONTRIBUTIONS TO THE MORPHOLOGY OF POLLEN FROM SOME VARIETIES OF MALUS DOMESTICA, PYRUS COMMUNIS, PRUNUS DOMESTICA, PRUNUS PERSICA AND PRUNUS ARMENIACA

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    Nicoleta IANOVICI

    2010-01-01

    Full Text Available The objective of this study was to compare Rosaceae genotypes from for their pollen viability and morphology. The pollen of some varieties of Malus domestica, Pyrus communis, Prunus domestica, Prunus persica and Prunus armeniaca was identified. Pollen from mature anthers was collected. Pollen grains of all genera of Rosaceae surveyed occur as radially symmetric isopolar monads. The main aspect studied were the shape of pollen in the polar view (polar perimeter and polar area of pollen. Shape of pollen is triangular-obtuse-convex in polar view. The pollen class is trizonocolpate-obtus-triangular while the sculpturing of exine surface is striate. The number of colpi is three while the spines are absent. Apart from fully developed pollen grains, also much smaller, not completely developed pollen were found in the samples of the examined species. The viability of the pollen was determined on 1% 2,3,5-triphenyl tetrazolium chloride (TTC. Viable, semi-viable and dead pollen numbers and their percentages were determined. This stain test may be used to determine pollen viability in these species to provide only a rough estimate of viability. The results presented here are important for improving our understanding of Rosaceae reproduction biology. Knowledge of reproduction biology, particularly pollen viability and quality, is critical for the newly-developed cultivars.

  3. Palynology of the Genus Stachytarpheta Vahl. (Verbenaceae

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    Olubukola ADEDEJI

    2010-12-01

    Full Text Available The exine morphology of pollen grains of Stachytarpheta indica (Linn. Vahl, Stachytarpheta cayennensis (Rich. Vahl and Stachytarpheta angustifolia (Mill. Vahl is reported. This study was carried out with a light microscope. Pollen grains from fresh anthers were collected and aceolysed. Statistical analysis used to analyse the data collected include cluster analysis, correlation analysis, similarity and distance indices. The pollen grains are spheroidal to oblate to sub-oblate in shape. They are aperturate, both colpate and porate. Tricolpate types occur most frequently, acolpate, monocolpate, bicolpate and tetracolpate types less frequently. The multicolpate and multiporate attributes in all the species indicate that the genus is not primitive in evolutionary history and this species probably, evolved around in the same time. According to the size, the pollen grains of the genus falls into groups permagna (pollen diameter 100-200 ?m and giganta (pollen diameter greater than 200 ?m. S. cayennensis and S. anguistifolia belong to group permagna and S. indica only in the group giganta. This separates S. indica from the other two species. The large pollen grain size in the genus clearly supports the fact that the flowers in the genus are more insect-and-bird pollinated than wind pollinated. The similarity and distance indices of the species showed that S. cayennensis and S. angustifolia are the closest. S. indica is closer to S. angustifolia but farther from S. cayennensis.

  4. Not just gene expression: 3D implications of chromatin modifications during sexual plant reproduction.

    Science.gov (United States)

    Dukowic-Schulze, Stefanie; Liu, Chang; Chen, Changbin

    2018-01-01

    DNA methylation and histone modifications are epigenetic changes on a DNA molecule that alter the three-dimensional (3D) structure locally as well as globally, impacting chromatin looping and packaging on a larger scale. Epigenetic marks thus inform higher-order chromosome organization and placement in the nucleus. Conventional epigenetic marks are joined by chromatin modifiers like cohesins, condensins and membrane-anchoring complexes to support particularly 3D chromosome organization. The most popular consequences of epigenetic modifications are gene expression changes, but chromatin modifications have implications beyond this, particularly in actively dividing cells and during sexual reproduction. In this opinion paper, we will focus on epigenetic mechanisms and chromatin modifications during meiosis as part of plant sexual reproduction where 3D management of chromosomes and re-organization of chromatin are defining features and prime tasks in reproductive cells, not limited to modulating gene expression. Meiotic chromosome organization, pairing and synapsis of homologous chromosomes as well as distribution of meiotic double-strand breaks and resulting crossovers are presumably highly influenced by epigenetic mechanisms. Special mobile small RNAs have been described in anthers, where these so-called phasiRNAs seem to direct DNA methylation in meiotic cells. Intriguingly, many of the mentioned developmental processes make use of epigenetic changes and small RNAs in a manner other than gene expression changes. Widening our approaches and opening our mind to thinking three-dimensionally regarding epigenetics in plant development holds high promise for new discoveries and could give us a boost for further knowledge.

  5. A pentatricopeptide repeat protein restores nap cytoplasmic male sterility in Brassica napus.

    Science.gov (United States)

    Liu, Zhi; Dong, Faming; Wang, Xiang; Wang, Tao; Su, Rui; Hong, Dengfeng; Yang, Guangsheng

    2017-07-10

    Two forms of male-sterile cytoplasm, designated nap and pol, are found in the oilseed rape species, Brassica napus. The nap cytoplasm is observed in most B. napus varieties, and it confers male sterility on a limited number of cultivars that lack the corresponding restorer gene, Rfn. In the present study, using linkage analysis in combination with 5652 BC1 progeny derived from a cross between a nap cytoplasmic male sterility (CMS) line 181A and a restorer line H5, we delimited the Rfn gene to a 10.5 kb region on chromosome A09, which contained three putative ORFs. Complementation by transformation rescue revealed that the introduction of ORF2, which encodes a pentatricopeptide repeat (PPR) protein, resulted in the recovery of fertility of nap CMS plants. Expression analysis suggested that the Rfn was highly expressed in flower buds and it was preferentially expressed in the tapetum and meiocytes during anther development. Further RNA gel blots and immunodetection suggested that the Rfn gene may play a complicated role in restoring the nap CMS. Our work laid the foundation for dissecting the molecular basis of CMS fertility restoration and the nuclear-mitochondrial interactions in CMS/Rf systems. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  6. Mimicry in plant-parasitic fungi.

    Science.gov (United States)

    Ngugi, Henry K; Scherm, Harald

    2006-04-01

    Mimicry is the close resemblance of one living organism (the mimic) to another (the model), leading to misidentification by a third organism (the operator). Similar to other organism groups, certain species of plant-parasitic fungi are known to engage in mimetic relationships, thereby increasing their fitness. In some cases, fungal infection can lead to the formation of flower mimics (pseudo flowers) that attract insect pollinators via visual and/or olfactory cues; these insects then either transmit fungal gametes to accomplish outcrossing (e.g. in some heterothallic rust fungi belonging to the genera Puccinia and Uromyces) or vector infectious spores to healthy plants, thereby spreading disease (e.g. in the anther smut fungus Microbotryum violaceum and the mummy berry pathogen Monilinia vaccinii-corymbosi). In what is termed aggressive mimicry, some specialized plant-parasitic fungi are able to mimic host structures or host molecules to gain access to resources. An example is M. vaccinii-corymbosi, whose conidia and germ tubes, respectively, mimic host pollen grains and pollen tubes anatomically and physiologically, allowing the pathogen to gain entry into the host's ovary via stigma and style. We review these and other examples of mimicry by plant-parasitic fungi and some of the mechanisms, signals, and evolutionary implications.

  7. Meiotic chromosome behaviours in M1 generation of bread wheat irradiated by gamma-rays

    International Nuclear Information System (INIS)

    Watanabe, Y.; Takato, S.

    1982-01-01

    Growing plants of bread wheat (Triticum aestivum L. 2 n=6x=42, AABBDD) were subjected to acute or chronic irradiation by gamma-rays from 60Co and meiotic chromosome behaviours of PMCS in M 1 generation were cytologically compared. Both acute and chronic irradiations produced different types of chromosomal aberrations at the meiotic stages. Among them, translocation type was the most frequent, followed by univalent type. A mixed type, i. e. translocation accompanying one or more univalents was often detected. Even normal type which lacked translocation and univalent included laggards and briclges without exception. Other meiotic abnormalities such as deletion, iso-chromosome and micronuclei were observed frequently in both treatments. Dose dependency of translocation frequency was not recognized in this experiment. In chronic irradiation, different chromosome numbers and meiotic behaviours were found not only among florets of a spike but also among anthers of a floret. A number of plants with aneuploid-like grass types occurred at a high frequency in M 1 , especially with low exposure

  8. CYP703 Is an Ancient Cytochrome P450 in Land Plants Catalyzing in-Chain Hydroxylation of Lauric Acid to Provide Building Blocks for Sporopollenin Synthesis in Pollen[W

    Science.gov (United States)

    Morant, Marc; Jørgensen, Kirsten; Schaller, Hubert; Pinot, Franck; Møller, Birger Lindberg; Werck-Reichhart, Danièle; Bak, Søren

    2007-01-01

    CYP703 is a cytochrome P450 family specific to land plants. Typically, each plant species contains a single CYP703. Arabidopsis thaliana CYP703A2 is expressed in the anthers of developing flowers. Expression is initiated at the tetrad stage and restricted to microspores and to the tapetum cell layer. Arabidopsis CYP703A2 knockout lines showed impaired pollen development and a partial male-sterile phenotype. Scanning electron and transmission electron microscopy of pollen from the knockout plants showed impaired pollen wall development with absence of exine. The fluorescent layer around the pollen grains ascribed to the presence of phenylpropanoid units in sporopollenin was absent in the CYP703A2 knockout lines. Heterologous expression of CYP703A2 in yeast cells demonstrated that CYP703 catalyzes the conversion of medium-chain saturated fatty acids to the corresponding monohydroxylated fatty acids, with a preferential hydroxylation of lauric acid at the C-7 position. Incubation of recombinant CYP703 with methanol extracts from developing flowers confirmed that lauric acid and in-chain hydroxy lauric acids are the in planta substrate and product, respectively. These data demonstrate that in-chain hydroxy lauric acids are essential building blocks in sporopollenin synthesis and enable the formation of ester and ether linkages with phenylpropanoid units. This study identifies CYP703 as a P450 family specifically involved in pollen development. PMID:17496121

  9. CYP703 is an ancient cytochrome P450 in land plants catalyzing in-chain hydroxylation of lauric acid to provide building blocks for sporopollenin synthesis in pollen.

    Science.gov (United States)

    Morant, Marc; Jørgensen, Kirsten; Schaller, Hubert; Pinot, Franck; Møller, Birger Lindberg; Werck-Reichhart, Danièle; Bak, Søren

    2007-05-01

    CYP703 is a cytochrome P450 family specific to land plants. Typically, each plant species contains a single CYP703. Arabidopsis thaliana CYP703A2 is expressed in the anthers of developing flowers. Expression is initiated at the tetrad stage and restricted to microspores and to the tapetum cell layer. Arabidopsis CYP703A2 knockout lines showed impaired pollen development and a partial male-sterile phenotype. Scanning electron and transmission electron microscopy of pollen from the knockout plants showed impaired pollen wall development with absence of exine. The fluorescent layer around the pollen grains ascribed to the presence of phenylpropanoid units in sporopollenin was absent in the CYP703A2 knockout lines. Heterologous expression of CYP703A2 in yeast cells demonstrated that CYP703 catalyzes the conversion of medium-chain saturated fatty acids to the corresponding monohydroxylated fatty acids, with a preferential hydroxylation of lauric acid at the C-7 position. Incubation of recombinant CYP703 with methanol extracts from developing flowers confirmed that lauric acid and in-chain hydroxy lauric acids are the in planta substrate and product, respectively. These data demonstrate that in-chain hydroxy lauric acids are essential building blocks in sporopollenin synthesis and enable the formation of ester and ether linkages with phenylpropanoid units. This study identifies CYP703 as a P450 family specifically involved in pollen development.

  10. Critical Roles of Vacuolar Invertase in Floral Organ Development and Male and Female Fertilities Are Revealed through Characterization of GhVIN1-RNAi Cotton Plants.

    Science.gov (United States)

    Wang, Lu; Ruan, Yong-Ling

    2016-05-01

    Seed number and quality are key traits determining plant fitness and crop yield and rely on combined competence in male and female fertilities. Sucrose metabolism is central to reproductive success. It remains elusive, though, how individual sucrose metabolic enzymes may regulate the complex reproductive processes. Here, by silencing vacuolar invertase (VIN) genes in cotton (Gossypium hirsutum) reproductive organs, we revealed diverse roles that VIN plays in multiple reproductive processes. A set of phenotypic and genetic studies showed significant reductions of viable seeds in GhVIN1-RNAi plants, attributed to pollination failure and impaired male and female fertilities. The former was largely owing to the spatial mismatch between style and stamen and delayed pollen release from the anthers, whereas male defects came from poor pollen viability. The transgenic stamen exhibited altered expression of the genes responsible for starch metabolism and auxin and jasmonic acid signaling. Further analyses identified the reduction of GhVIN expression in the seed coat as the major cause for the reduced female fertility, which appeared to disrupt the expression of some key genes involved in trehalose and auxin metabolism and signaling, leading to programmed cell death or growth repression in the filial tissues. Together, the data provide an unprecedented example of how VIN is required to synchronize style and stamen development and the formation of male and female fertilities for seed development in a crop species, cotton. © 2016 American Society of Plant Biologists. All Rights Reserved.

  11. Classical macroautophagy in Lobivia rauschii (Cactaceae) and possible plastidial autophagy in Tillandsia albida (Bromeliaceae) tapetum cells.

    Science.gov (United States)

    Papini, Alessio; Mosti, Stefano; van Doorn, Wouter G

    2014-05-01

    The tapetum in anthers is a tissue that undergoes programmed cell death (PCD) during the production of pollen. We observed two types of autophagy prior to cell death. In Lobivia rauschii (Cactaceae), tapetum cells showed plant-type autophagosomes-autolysosomes, which have been found previously exclusively in root meristem cells. The autophagic structures were formed by a network of tubules which apparently merged laterally, thereby sequestering a portion of the cytoplasm. The organelles observed in the sequestered material included multilamellar bodies, which have not been reported earlier in these organelles. By contrast, Tillandsia albida (Bromeliaceae) tapetum cells contained no such organelles but showed plastids that might possibly carry out autophagy, as they contained portions of the cytoplasm similar to the phenomenon reported earlier in Phaseolus and Dendrobium. However, the ultrastructure of the T. albida plastids was different from that in the previous reports. It is concluded that in L. rauschii classical plant macroautophagy was involved in degradation of the cytoplasm, while in T. albida such classical macroautophagy was not observed. Instead, the data in T. albida suggested the hypothesis that plastids are able to carry out degradation of the cytoplasm.

  12. Triuridaceae fossil flowers from the Upper Cretaceous of New Jersey.

    Science.gov (United States)

    Gandolfo, María A; Nixon, Kevin C; Crepet, William L

    2002-12-01

    We report here on a series of fossil flowers exhibiting a mosaic of characters present in the extant monocot family Triuridaceae. Phylogenetic analyses of morphological data from a broad sample of extant monocots confirm the affinities of the fossils with modern Triuridaceae. The fossil flowers were collected from outcrops of the Raritan Formation (Upper Cretaceous, ∼90 million years before present), New Jersey, USA. These are the oldest known unequivocal monocot flowers. Because other reports of "earliest" monocots are all based on equivocal character suites and/or ambiguously preserved fossil material, the Triuridaceae fossils reported here should also be considered as the oldest unequivocal fossil monocots. Flowers are minute and unisexual (only male flowers are known); the perianth is composed of six tepals, lacking stomata. The unicyclic androecium is of three stamens with dithecal, monosporangiate, extrorse anthers that open by longitudinal slits. The endothecium has U-shaped type thickenings. Pollen grains are monosulcate. The triurid fossil flowers can be separated into three distinctive species. On the basis of phylogenetic analyses of morphological characters, the fossil taxa nest within the completely saprophytic achlorophyllous Triuridaceae supporting the interpretation that the extinct plants were also achlorophyllous and saprophytic. If so, this represents the earliest known fossil occurrence of the saprophytic/mycotrophic habit in angiosperms.

  13. Breeding system and bumblebee drone pollination of an explosively pollen-releasing plant, Meliosma tenuis (Sabiaceae).

    Science.gov (United States)

    Wong Sato, A A; Kato, M

    2018-02-02

    Explosive pollen release is a mechanism used by some angiosperms that serves to attach pollen to a pollinator's body. It is usually adopted by species with zygomorphic tubular flowers and pollinated by birds and bees. The tree genus Meliosma (Sabiaceae, Proteales) has unique disc-like flowers that are externally actinomorphic, but internally zygomorphic, and release pollen explosively. To elucidate the adaptive significance of explosive pollen release, we observed flowering behaviour, the breeding system and pollinator visits to flowers of the Japanese species Meliosma tenuis in a temperate forest. Flowers bloomed in June and were nectariferous and protandrous. Explosive pollen release was triggered by slight tactile stimuli to anther filaments or staminodes in male-stage flowers. Because pollen cannot come into contact with the pistils enclosed by staminodes, M. tenuis is functionally protandrous. Artificial pollination treatments revealed that M. tenuis is allogamous. The dominant flower visitors were nectar-seeking drones of the bumblebee species Bombus ardens (Apidae). The drones' behaviour, pollen attachment on their bodies and fruit set of visit-restricted flowers suggest that they are the only agent triggering the explosive pollen release mechanism, and are the main pollinator of M. tenuis. The finding that bumblebee workers rarely visit these flowers suggests that the explosive pollen release has another function, namely to discourage pollen-harvesting bumblebee workers. © 2018 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

  14. Glycoalkaloid profile in potato haploids derived from solanum tuberosum-S. bulbocastanum somatic hybrids.

    Science.gov (United States)

    Carputo, Domenico; Savarese, Salvatore; Andolfi, Anna; Aversano, Riccardo; Cimmino, Alessio; Frusciante, Luigi; Evidente, Antonio

    2010-08-01

    Cultivated and wild potato species synthesize a wide variety of steroidal glycoalkaloids (GA) that may affect either human health or biotic stress resistance. Therefore, GA composition must be a major criterion in the evaluation of breeding products when species genomes are merged and/or manipulated. This work reports the results of GA analysis performed on unique haploid (2n=2x=24) plants obtained from tetraploid (2n=4x=48) Solanum bulbocastanum-S. tuberosum hybrids through in vitro anther culture. Glycoalkaloids were extracted from tubers and analyzed by HPLC. Haploids generally showed the occurrence of parental GA. However, in several cases loss of parental GA and gain of new GA lacking in the parents was observed. It may be hypothesized that new GA profiles of our haploids is the result of either genetic recombination or combinatorial biochemistry events. To highlight differences between haploids and parents, soluble proteins and antioxidant activities were also determined. Both were always higher in haploids compared to their parents. The nature of the newly formed GAs will be further investigated, because they may represent new metabolites that can be used against pest and diseases, or are useful for human health.

  15. Flowering biology of three taxa of the genus Scilla L. (Hyacinthaceae and flower visitation by pollinating insects

    Directory of Open Access Journals (Sweden)

    Beata Żuraw

    2012-12-01

    Full Text Available Squill of the family Hyacinthaceae is a small bulb perennial. The present study on flowering and pollination of Scilla sibirica Andr., S. sibirica 'Alba', and S. bifolia L. was conducted in the years 1995, 1997, and 1999 in the Botanical Garden of the Maria Curie-Skłodowska University in Lublin. The plants flowered from the end of March until the middle of May. The duration of flowering of individual taxa was similar and it averaged 20 days (Scilla sibirica, 21 days (S. sibirica 'Alba', and 23 days (S. bifolia. The opening of flower buds always started around 9.00 am and lasted, depending on the taxon, until 3.00 pm (Scilla sibirica 'Alba', 4.00 pm (S. bifolia, and 5.00 pm (S. sibirica. The flowers were visited by bees (Apoidea, primarily the honey bee (Apis mellifera L., bumblebee (Bombus L., and solitary bees. Numerous honey bee foragers were observed; they bit through the anther walls and even attempted to open still closed flower buds in order to reach the pollen.

  16. Especie nueva de Justicia (Acanthaceae del bosque tropical caducifolio de la costa de Oaxaca, México A new species of Justicia (Acanthaceae from the tropical deciduous forest of the Oaxacan coast, Mexico

    Directory of Open Access Journals (Sweden)

    Salvador Acosta-Castellanos

    2007-06-01

    Full Text Available Se describe Justicia salma-margaritae del bosque tropical caducifolio de la costa de Oaxaca, México. La nueva especie se agrupa en Justicia sección Sarotheca y se caracteriza por la combinación de sus inflorescencias espigadas compuestas, cáliz desigualmente 5-lobado, tecas de las anteras sin apéndices, polen 2-colporado con 4 filas de ínsulas en el área tremal, cápsulas pubescentes y semillas tuberculadas. Sin embargo, se puede diferenciar claramente de las especies previamente descritas por la peculiar pubescencia glandular que presentan las brácteas, bractéolas y segmentos del cáliz.Justicia salma-margaritae is described from the tropical deciduous forest of the Oaxacan coast, Mexico. It is placed in Justicia sect. Sarotheca on account of a combination of morphological characters: compound spicate inflorescences, unequally 5-lobed calyces, unappendaged anther thecae, 2-colporate pollen with 4 rows of insulae in the trema area, pubescent capsules and tuberculate seeds. However, it may be clearly differentiated from the previously described species of that section by the peculiar glandular pubescence of bracts, bracteoles and calyces.

  17. Monitoring homologous recombination in rice (Oryza sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Yang Zhuanying; Tang Li [Guangdong Provincial Key Lab of Biotechnology for Plant Development, College of Life Sciences, South China Normal University, Guangzhou 510631 (China); Li Meiru [South China Botanic Garden, Chinese Academy of Sciences, Guangzhou 510650 (China); Chen Lei; Xu Jie [Guangdong Provincial Key Lab of Biotechnology for Plant Development, College of Life Sciences, South China Normal University, Guangzhou 510631 (China); Wu Goujiang [South China Botanic Garden, Chinese Academy of Sciences, Guangzhou 510650 (China); Li Hongqing, E-mail: hqli@scnu.edu.cn [Guangdong Provincial Key Lab of Biotechnology for Plant Development, College of Life Sciences, South China Normal University, Guangzhou 510631 (China)

    2010-09-10

    Here we describe a system to assay homologous recombination during the complete life cycle of rice (Oryza sativa L.). Rice plants were transformed with two copies of non-functional GUS reporter overlap fragments as recombination substrate. Recombination was observed in all plant organs examined, from the seed stage until the flowering stage of somatic plant development. Embryogenic cells exhibited the highest recombination ability with an average of 3 x 10{sup -5} recombination events per genome, which is about 10-fold of that observed in root cells, and two orders of that observed in leaf cells. Histological analysis revealed that recombination events occurred in diverse cell types, but preferentially in cells with small size. Examples of this included embryogenic cells in callus, phloem cells in the leaf vein, and cells located in the root apical meristem. Steady state RNA analysis revealed that the expression levels of rice Rad51 homologs are positively correlated with increased recombination rates in embryogenic calli, roots and anthers. Finally, radiation treatment of plantlets from distinct recombination lines increased the recombination frequency to different extents. These results showed that homologous recombination frequency can be effectively measured in rice using a transgene reporter assay. This system will facilitate the study of DNA damage signaling and homologous recombination in rice, a model monocot.

  18. Finding candidate genes under positive selection in Non-model species: examples of genes involved in host specialization in pathogens.

    Science.gov (United States)

    Aguileta, G; Lengelle, J; Marthey, S; Chiapello, H; Rodolphe, F; Gendrault, A; Yockteng, R; Vercken, E; Devier, B; Fontaine, M C; Wincker, P; Dossat, C; Cruaud, C; Couloux, A; Giraud, T

    2010-01-01

    Numerous genes in diverse organisms have been shown to be under positive selection, especially genes involved in reproduction, adaptation to contrasting environments, hybrid inviability, and host-pathogen interactions. Looking for genes under positive selection in pathogens has been a priority in efforts to investigate coevolution dynamics and to develop vaccines or drugs. To elucidate the functions involved in host specialization, here we aimed at identifying candidate sequences that could have evolved under positive selection among closely related pathogens specialized on different hosts. For this goal, we sequenced c. 17,000-32,000 ESTs from each of four Microbotryum species, which are fungal pathogens responsible for anther smut disease on host plants in the Caryophyllaceae. Forty-two of the 372 predicted orthologous genes showed significant signal of positive selection, which represents a good number of candidate genes for further investigation. Sequencing 16 of these genes in 9 additional Microbotryum species confirmed that they have indeed been rapidly evolving in the pathogen species specialized on different hosts. The genes showing significant signals of positive selection were putatively involved in nutrient uptake from the host, secondary metabolite synthesis and secretion, respiration under stressful conditions and stress response, hyphal growth and differentiation, and regulation of expression by other genes. Many of these genes had transmembrane domains and may therefore also be involved in pathogen recognition by the host. Our approach thus revealed fruitful and should be feasible for many non-model organisms for which candidate genes for diversifying selection are needed.

  19. Reproductive failure in Arabidopsis thaliana under transient carbohydrate limitation: flowers and very young siliques are jettisoned and the meristem is maintained to allow successful resumption of reproductive growth.

    Science.gov (United States)

    Lauxmann, Martin A; Annunziata, Maria G; Brunoud, Géraldine; Wahl, Vanessa; Koczut, Andrzej; Burgos, Asdrubal; Olas, Justyna J; Maximova, Eugenia; Abel, Christin; Schlereth, Armin; Soja, Aleksandra M; Bläsing, Oliver E; Lunn, John E; Vernoux, Teva; Stitt, Mark

    2016-04-01

    The impact of transient carbon depletion on reproductive growth in Arabidopsis was investigated by transferring long-photoperiod-grown plants to continuous darkness and returning them to a light-dark cycle. After 2 days of darkness, carbon reserves were depleted in reproductive sinks, and RNA in situ hybridization of marker transcripts showed that carbon starvation responses had been initiated in the meristem, anthers and ovules. Dark treatments of 2 or more days resulted in a bare-segment phenotype on the floral stem, with 23-27 aborted siliques. These resulted from impaired growth of immature siliques and abortion of mature and immature flowers. Depolarization of PIN1 protein and increased DII-VENUS expression pointed to rapid collapse of auxin gradients in the meristem and inhibition of primordia initiation. After transfer back to a light-dark cycle, flowers appeared and formed viable siliques and seeds. A similar phenotype was seen after transfer to sub-compensation point irradiance or CO2 . It also appeared in a milder form after a moderate decrease in irradiance and developed spontaneously in short photoperiods. We conclude that Arabidopsis inhibits primordia initiation and aborts flowers and very young siliques in C-limited conditions. This curtails demand, safeguarding meristem function and allowing renewal of reproductive growth when carbon becomes available again. © 2015 John Wiley & Sons Ltd.

  20. Floral development at multiple spatial scales in Polygonum jucundum (Polygonaceae), a distylous species with broadly open flowers.

    Science.gov (United States)

    Huang, Lan-Jie; Fu, Wen-Long; Wang, Xiao-Fan

    2014-01-01

    Distyly, a special polymorph, has evolved in many groups of angiosperms and has attracted attention since Darwin's time. Development studies on distylous taxa have helped us to understand the evolutionary process of this polymorph, but most of these studies focus on species with narrowly tubular corolla. Here, we studied the floral development of Polygonum jucundum, a distylous species with broadly open flowers, at multiple spatial scales. Results showed that the difference in stigma height between flowers of the two morphs was caused by differences in style growth throughout the entire floral development process. The observed difference in anther heights between the two morphs was because the filaments grew faster in short-styled (SS) than in long-styled (LS) flowers in the later stages of floral development. In addition, the longer styles in LS flowers than in SS flowers was because of faster cell division in the early stages of floral development. However, SS flowers had longer filaments than LS flowers primarily because of greater cell elongation. These results indicate that floral development in P. jucundum differs from that of distylous taxa with floral tubes shown in previous studies. Further, we conclude that the presence of distyly in species with open flowers is a result of convergent evolution.

  1. Analysis of five rice 4-coumarate:coenzyme A ligase enzyme activity and stress response for potential roles in lignin and flavonoid biosynthesis in rice

    International Nuclear Information System (INIS)

    Sun, Haiyan; Li, Ying; Feng, Shengqiu; Zou, Weihua; Guo, Kai; Fan, Chunfen; Si, Shengli

    2013-01-01

    Highlights: ► 4CLs play important roles in both lignin and flavonoids biosynthesis. ► PA and FA are the two main substrates of 4CL (Os4CL1/3/4/5) for lignin biosynthesis. ► Os4CL2 is suggested for flavonoid formation in defense against UV radiation. -- Abstract: 4-Coumarate:coenzyme A ligase (4CL) catalyzes the conversion of hydroxycinnamates into corresponding CoA esters for biosynthesis of flavonoids and lignin. In this study, five members of the 4CL gene family from rice were cloned and analyzed. Recombinant 4CL data revealed that 4-coumaric acid and ferulic acid were the two main substrates of 4CL (Os4CL1/3/4/5) for monolignol biosynthesis in rice. Os4CL2 was specifically expressed in the anther and was strongly activated by UV irradiation, suggesting its potential involvement in flavonoid formation. Moreover, bioinformatics analysis showed that the existence of valine residue at the substrate-binding pocket may mainly affect rice 4CL activities toward sinapic acid

  2. Analysis of five rice 4-coumarate:coenzyme A ligase enzyme activity and stress response for potential roles in lignin and flavonoid biosynthesis in rice

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Haiyan [National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070 (China); Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070 (China); College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); School of Biology and Food Engineering, Changshu Institute of Technology, Changshu 215500 (China); Li, Ying; Feng, Shengqiu; Zou, Weihua [National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070 (China); Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070 (China); College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Guo, Kai [National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070 (China); Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070 (China); College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Fan, Chunfen [National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070 (China); Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070 (China); College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Si, Shengli [National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070 (China); Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070 (China); College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); and others

    2013-01-18

    Highlights: ► 4CLs play important roles in both lignin and flavonoids biosynthesis. ► PA and FA are the two main substrates of 4CL (Os4CL1/3/4/5) for lignin biosynthesis. ► Os4CL2 is suggested for flavonoid formation in defense against UV radiation. -- Abstract: 4-Coumarate:coenzyme A ligase (4CL) catalyzes the conversion of hydroxycinnamates into corresponding CoA esters for biosynthesis of flavonoids and lignin. In this study, five members of the 4CL gene family from rice were cloned and analyzed. Recombinant 4CL data revealed that 4-coumaric acid and ferulic acid were the two main substrates of 4CL (Os4CL1/3/4/5) for monolignol biosynthesis in rice. Os4CL2 was specifically expressed in the anther and was strongly activated by UV irradiation, suggesting its potential involvement in flavonoid formation. Moreover, bioinformatics analysis showed that the existence of valine residue at the substrate-binding pocket may mainly affect rice 4CL activities toward sinapic acid.

  3. Several New Aspects of the Foraging Behavior of Osmia cornifrons in an Apple Orchard

    Directory of Open Access Journals (Sweden)

    Shogo Matsumoto

    2010-01-01

    Full Text Available We investigated the foraging behavior of Osmia cornifrons Radoszkowski, which is a useful pollinator in apple orchards consisting of only one kind of commercial cultivars such as “Fuji”, and of different types of pollinizers, such as the red petal type, “Maypole” or “Makamik”. It was confirmed that, in terms of the number of foraging flowers per day, visiting flowers during low temperatures, strong wind, and reduced sunshine in an apple orchard, O. cornifrons were superior to honeybees. We indicated that O. cornifrons seemed to use both petals and anthers as foraging indicator, and that not only female, but also males contributed to apple pollination and fertilization by the pollen grains attached to them from visiting flowers, including those at the balloon stage. It was confirmed that O. cornifrons acts as a useful pollinator in an apple orchard consisting of one kind of cultivar with pollinizers planted not more than 10 m from commercial cultivars.

  4. [Effect of rye Secale cereale L. chromosomes 1R and 3R on polyembryony expression in hybrid combinations between (Hordeum vulgare L.)-Triticum aestivum L. alloplasmic recombinant lines and wheat T. aestivum L.-rye S. cereale L. substitution lines].

    Science.gov (United States)

    Pershina, L A; Rakovtseva, T S; Belova, L I; Deviatkina, E P; Silkova, O G; Kravtsova, L A; Shchapova, A I

    2007-07-01

    The effect of rye chromosomes on polyembryony was studied for reciprocal hybrid combinations between (Hordeum vulgare L.)-Triticum aestivum L. alloplasmic recombinant lines and five wheat T. aestivum L. (cultivar Saratovskaya 29)-rye Secale cereale L. (cultivar Onokhoiskaya) substitution lines: IR(1D), 2R(2D), 3R(3B), 5R(5A), and 6R(6A), and for direct hybrid combinations between the [H. marinum ssp. gussoneanum (H. geniculatum All.)]-T. aestivum alloplasmic recombinant line and the wheat-rye substitution lines 1R (1A), 1R (1D), and 3R(3B). Chromosomes 1R and 3R of rye cultivar Onokhoiskaya proved to affect the expression of polyembryony in the hybrid combinations that involved the alloplasmic recombinant lines of common wheat as maternal genotypes. Based on this finding, polyembryony was regarded as a phenotypic expression of nuclear-cytoplasmic interactions where an important role is played by rye chromosomes 1R and 3R and the H. vulgare cytoplasm. Consideration is given to the association between the effect of rye chromosomes 1R and 3R on polyembryony in the [(Hordeum)-T. aestivum x wheat-rye substitution lines] hybrid combinations and their stimulating effect on the development on angrogenic embryoids in isolated anther cultures of the wheat-rye substitution lines.

  5. Comparative proteomic analysis of a membrane-enriched fraction from flag leaves reveals responses to chemical hybridization agent SQ-1 in wheat

    Directory of Open Access Journals (Sweden)

    Qilu eSong

    2015-08-01

    Full Text Available The induction of wheat male fertile lines by using the chemical hybridizing agent SQ-1 (CHA-SQ-1 is an effective approach in the utilization of heterosis; however, the molecular basis of male fertility remains unknown. Wheat flag leaves are the initial receptors of CHA-SQ-1 and their membrane structure plays a vital role in response to CHA-SQ-1 stress. To investigate the response of wheat flag leaves to CHA-SQ-1 stress, we compared their quantitative proteomic profiles in the absence and presence of CHA-SQ-1. Our results indicated that wheat flag leaves suffered oxidative stress during CHA-SQ-1 treatments. Leaf O2-, H2O2, and malonaldehyde levels were significantly increased within 10 h after CHA-SQ-1 treatment, while the activities of major antioxidant enzymes such as superoxide dismutase, catalase, and guaiacol peroxidase were significantly reduced. Proteome profiles of membrane-enriched fraction showed a change in the abundance of a battery of membrane proteins involved in multiple biological processes. These variable proteins mainly impaired photosynthesis, ATP synthesis protein mechanisms and were involved in the response to stress. These results provide an explanation of the relationships between membrane proteomes and anther abortion and the practical application of CHA for hybrid breeding.

  6. IMPROVING WHEAT TRITICUM AESTIVUM L. BY INTERSPECIFIC AND INTERGENERIC HYBRIDIZATION WITH POACEAE FAMILY SPECIES

    Directory of Open Access Journals (Sweden)

    Czaplicki A.Z.

    2012-08-01

    Full Text Available The related species of the family Poaceae (Triticeae are the source of unprecedented new genes that allow the extension of genetic variation of common wheat Triticum aestivum L. These species have similar homoeologous chromosomes and rDNA sequences very similar to T. aestivum L. [1-3]. This allows the introgression of alien genes and their incorporation into the genomes A, B and D of wheat, where they can function permanently in the wheat genetic systems. Many of them have already been transferred to the varieties of T. aestivum L. [4].The experimental material consisted of 28 lines of winter wheat obtained using the interspecific and intergeneric hybridization of T. aestivum L. with alien species T. durum Desf., T. timopheevii Zhuk., Lolium perenne L. and Aegilops speltoides Taush. Among them, 15 lines were developed from the cross-combination with tetraploid species (AABB T. durum Desf., 4 lines from the combination with other tetraploid species of different genome composition (AAGG T. timopheevii Zhuk., 4 lines from cross with L. perenne L. and 5 lines were the double hybrids (three-generic derived with two related species, T. durum Desf. (AABB and Ae. speltoides Taush (BB.The anther culture method was used for obtaining DH lines from these interspecific and intergeneric hybrids. In in vitro culture 124 green plants were regenerated. The method of cluster analysis grouped hybrids in terms of comprehensive general similarity of the studied traits.

  7. Screening for rice mutant of resistance to piricularia oryzae by irradiation and in vitro technique

    International Nuclear Information System (INIS)

    Wang Cailian; Xu Gang; Chen Qiufang; Jin Wei

    2001-01-01

    The ability of callus formation and green plant regeneration was very different for different rice types and varieties in mature embryo. LS-5 was optimum medium for mature embryo. Increase in plant regeneration capacity was found with 100, 150 Gy gamma rays. The differentiation and regeneration of green plants were obviously improved when the anthers on induction medium were with 30 Gy of gamma rays. The change of free amino acids in subcultured callus tissue in rice were investigated after callus were treated with cultured filtrate from Piricularia oryzae. Fourteen kinds of free amino acid could be quantitatively analysed, among which, contents of serine and glutamate were the highest and made up about 20% of total amino acids respectively. The total amino acids in callus tissue of resistant varieties before treated with cultured filtrate were higher than that of susceptible varieties. However the total amino acids were decreased in the resistant varieties and increased in the susceptible varieties after treatment with the filtrate. Arginine was found in the variety of Zhen Kong No. 13. Disease resistance of R 2 plants screened with toxin was increased. Five mutants with resistance to Piricularia oryzae were selected

  8. Verhuellia is a segregate lineage in Piperaceae: more evidence from flower, fruit and pollen morphology, anatomy and development.

    Science.gov (United States)

    Samain, Marie-Stéphanie; Vrijdaghs, Alexander; Hesse, Michael; Goetghebeur, Paul; Jiménez Rodríguez, Francisco; Stoll, Alexandra; Neinhuis, Christoph; Wanke, Stefan

    2010-05-01

    The perianthless Piperales, i.e. Saururaceae and Piperaceae, have simple reduced flowers strikingly different from the other families of the order (e.g. Aristolochiaceae). Recent molecular phylogenies proved Verhuellia to be the first branch in Piperaceae, making it a promising subject to study the detailed structure and development of the flowers. Based on recently collected material, the first detailed study since 1872 was conducted with respect to morphology, anatomy and development of the inflorescence, pollen ultrastructure and fruit anatomy. Original scanning electron microscopy (SEM), transmission electron microscopy (TEM) and light microscopy (LM) observations on Verhuellia lunaria were compared with those of Piperaceae, Saururaceae and fossils. The inflorescence is an indeterminate spike with sessile flowers, each in the axil of a bract, developing in acropetal, helical succession. Flowers consist of two (occasionally three) stamens with basifixed tetrasporangiate anthers and latrorse dehiscence by a longitudinal slit. The gynoecium lacks a style but has 3-4 stigma branches and a single, basal orthotropous and unitegmic ovule. The fruit is a drupe with large multicellular epidermal protuberances. The pollen is very small, inaperturate and areolate, with hemispherical microechinate exine elements. Despite the superficial similarities with different genera of Piperaceae and Saururaceae, the segregate position of Verhuellia revealed by molecular phylogenetics is supported by morphological, developmental and anatomical data presented here. Unitegmic ovules and inaperturate pollen, which are synapomorphies for the genus Peperomia, are also present in Verhuellia.

  9. Floral Biology of Fluted Pumpkin (Telfairia occidentalis Hook. F.

    Directory of Open Access Journals (Sweden)

    Lawrence Stephen FAYEUN

    2016-12-01

    Full Text Available Knowledge of floral biology is essential to crop improvement. Ten genotypes of fluted pumpkin (Telfairia occidentalis were observed for floral morphology, phenology and insect visitation for two consecutive years. Functional dioecy of fluted pumpkin was confirmed, whereas none of the studied genotypes was monoecious. Floral structures differed significantly among the genotypes. Both male and female flowers were symmetrical, pentasepalous, fimbriate and non-bright pentapetalous, but male flowers were more numerous. Male inflorescences emerged from 11 to 14 weeks after planting and the female flower buds appeared about 4 weeks later. The flowering period of the male flowers was longer than that of female flowers and both gender flowering periods coincided for a specific interval. It took between 11 to 14 days from bud initiation to anthesis and flowering ceased when there were occurrences of successful fruits set. In both gender flowers petals started unfurling at around 6.00 pm and full bloom was achieved by dawn, while petal shrivelled at sun set (between 6.30 pm to 7.30 pm. The anthers dehisced at anthesis of the male flowers; the pollen grains were whitish and sticky. Only the male flowers have nectar and pollen and this may explain infrequent female flowers visitation. Hover flies (Cheilosia species were the major floral visitors observed.

  10. Biological characteristics of Edgeworthia tomentosa (Thunb.) Nakai flowers and antimicrobial properties of their essential oils.

    Science.gov (United States)

    Sun, Yanfang; Wang, Zhangqi; Li, Boqi; Sharopov, Farukh S; Wang, Pan; Sun, Yang; Liang, Zongsuo

    2017-09-01

    Edgeworthia tomentosa (Thunb.) Nakai belongs to Thymelaeaceae family, its alabastrum is used as the traditional Chinese medicine 'Buddleja Officinalis Maxim'. The present study was to elucidate the ultrastructure characteristics of the flower, the phytochemical composition of the aroma essential oils (EOs) and the relevant antimicrobial properties. There were exclusive characters of calyx, ovule, anther and pollen grain of the flowers under scanning electron microscopy. A total of 40 phytochemical components representing 98% of the EOs were successfully identified: monoterpenes and sesquiterpenes were the dominant terpenoids according to Kovats retention index and MS database. EOs exhibited a broad spectrum antimicrobial activity against Gram-positive and Gram-negative bacteria, the best bacteriostatic effect was against Diplococcus pneumonia with MIC and MBC values ranging between 7.8 and 62.5 and 26.0-71.0 μg/mL, respectively. These results demonstrate that the surface microscopic morphological characteristics of Edgeworthia chrysantha Lindl. flowers, are full-scale chemical composition and antimicrobial properties of the EOs.

  11. Production of intergeneric allotetraploid between autotetraploid non-heading Chinese cabbage (Brassica campestris ssp. chinensis Makino and autotetraploid radish (Raphanus sativus L.

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    Sun Cheng-Zhen

    2014-03-01

    Full Text Available Intergeneric hybrids between non-heading Chinese cabbage (Brassica campestris ssp. chinensis Makino; 2n = 4x = 40 and radish (Raphanus sativus L.; 2n = 4x = 36 were obtained through ovary culture and embryo rescue. Some hybrid embryos (0.11 per ovary were produced, but only 4 of them germinated. As most hybrid embryos failed to develop into plantlets directly, plants were regenerated by inducing shoots on the cultured cotyledon and inducing roots on the root induction medium. All hybrid plants were morphologically uniform. They resembled the non-heading Chinese cabbage in the long-lived habit, the plant status, the vernalization requirement and the petiole color, while the petiole shape, leaf venation pattern and flowers were more similar to those of radish. Upon examination of the flowers, these were found to have normal pistil, but rudimentary anthers with non-functional pollen grains. The somatic chromosome number of F1 plants was 38. Analysis of SSR banding patterns provided additional confirmation of hybridity.

  12. CsAP3: a cucumber homolog to Arabidopsis APETALA3 with novel characteristics

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    Jinjing Sun

    2016-08-01

    Full Text Available In our previous efforts to understand the regulatory mechanisms of cucumber unisexual flower development, we observed a stamen-specific down-regulation of the ethylene receptor CsETR1 in stage 6 female flowers of cucumber (Cucumis sativus L. This down-regulation is correlated with the primordial anther-specific DNA damage that characterizes inappropriate stamen development in cucumber female flowers. To understand how CsETR1 is down regulated in the stamen, we characterized a cucumber MADS box gene homologous to Arabidopsis AP3, CsAP3. We demonstrated that CsAP3 is functionally equivalent to the Arabidopsis B-class MADS gene AP3. However, three novel characteristics of CsAP3 were found. These include firstly, binding and activating CsETR1 promoter in vitro and in vivo; secondly, containing a GV repeat in its C-terminus, which is conserved in cucurbits and required for the transcription activation; and thirdly, decreased expression as the node number increases, which is similar to that found for CsETR1. These findings revealed not only the conserved function of CsAP3 as a B-class floral identity gene, but also its unique functions in regulation of female flower development in cucumber.

  13. Immunolocalization of the PmSUC1 sucrose transporter in Plantago major flowers and reporter-gene analyses of the PmSUC1 promoter suggest a role in sucrose release from the inner integument.

    Science.gov (United States)

    Lauterbach, C; Niedermeier, M; Besenbeck, R; Stadler, R; Sauer, N

    2007-05-01

    This paper presents a detailed analysis of the PmSUC1 gene from plantago major, of its promoter activity in Arabidopsis, and of the tissue specific localization of the encoded protein in Plantago. PmSUC1 promoter activity was detected in the innermost layer of the inner integument (the endothel) of Arabidopsis plants expressing the gene of the green fluorescent protein (GFP) under the control of the PmSUC1 promoter. This promoter activity was confirmed with a PmSUC1-specific antiserum that identified the PmSUC1 protein in the endothel of Plantago and of Arabidopsis plants expressing the PmSUC1 gene under the control of its own promoter. PmSUC1 promoter activity and PmSUC1 protein were also detected in pollen grains during maturation inside the anthers and in pollen tubes during and after germination. These results demonstrate that PmSUC1 is involved in sucrose partitioning to the young embryo and to the developing pollen and growing pollen tube. In the innermost cell layer of the inner integument, a tissue that delivers nutrients to the endosperm and the embryo, PmSUC1 may catalyze the release of sucrose into the apoplast.

  14. The effects of gamma-ray irradiation to strawberry (Fragaria x ananassa Duch.) calli on shoot regeneration, achene formation and morphological variations of regenerants

    International Nuclear Information System (INIS)

    Kasumi, Masakazu

    2002-01-01

    Strawberry (Fragaria x ananassa 'Nyoho') calli, derived from anthers, were irradiated with gamma -ray at dosages from 100 to 1,600 Gy (10 Gy · hr - 1) and their effects on callus growth, plant regeneration, and somaclonal variation were analyzed. The growth of callus and percentage of plant regeneration from the callus were reduced slightly at dosages less than 200 Gy, moderately at 400 Gy, and markedly above 800 Gy. Fruit growth associated with seed fertility (>50 % ) was morphologically normal at less than 100 Gy, whereas achene formation was significantly inhibited above 200 Gy. The percentages of morphological variation in regenerants formed from the irradiated callus were:13.7 (no irradiation), 18.6 (100 Gy), 66.0 (200 Gy), 75.7 (400 Gy), and 97.0 (800 Gy). Furthermore, higher dosages yielded wider variations, e.g., thick and small leaf, light leaf color, white flesh, and long fruit. In some regenerants, more than one morphological aberrations developed, some of which were transmissible to daughter plants. These results revealed that the irradiating strawberry callus with gamma - ray resulted in a higher degree and wider spectrum of somaclonal variation than did simple callus culture. (author)

  15. Haploidization of vegetable plants

    International Nuclear Information System (INIS)

    Michalik, B.

    2000-01-01

    Haploid plants have been widely introduced into vegetable crops breeding programmes, also in Poland. They can be produced by means of androgenesis in brassicas and pepper, gynogenesis in onion and beetroot, or induced parthenogenesis in vegetables belonging to the family Cucurbitaceae. Androgenesis in brassicas can be induced using both anther and microspore cultures. Efficiency of this process, provided the optimal medium composition, depends on conditions for culture initiation (thermal shock is necessary). Around 40% of developing androgenic plants of white cabbage and Brussels sprouts are diploids and after their self-pollination doubled-haploid lines can instantly be produced. Gynogenic development of haploid cells constituting the embryo sac in onion can be induced by a flower bud culture method. Firstly an induction medium is used, followed by a regeneration medium. Almost 90% of obtained plants are haploids and therefore the use of antimitotic agents is necessary in order to double their chromosome number. Induced parthogenesis is being applied in cucumber. Pollen previously exposed to ionising radiation is used for pollination, which causes the development of embryos being subsequently plated on a medium in order to develop haploid plants. Efficiency of the processes leading to the production of haploid plants in every species depends to a high degree on the genotype and growth conditions of donor plants. (author)

  16. Marker-assisted selection for the rice blast resistance gene Pi-ar in a backcross population

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    Leila Garcês de Araújo

    2010-01-01

    Full Text Available A doubled-haploid (DH population, obtained by anther culture of F1 plants from a cross between a highlysusceptible rice cultivar Lijiangxintuanheigu and the resistant somaclone (SC09, of the cultivar Araguaia, was used to identifyRAPD markers linked to the blast resistance gene Pi-ar. The 86 DH plants, inoculated with the race IB-9 of Magnaportheoryzae, segregated in 1:1 ratio of resistant and susceptible plants. Of the 67 primers used 31 produced DNA profiles thatdifferentiated resistant and susceptible bulks as well as the parental cultivars. The resistance gene was found linked to theprimer OPS162072 (‘AGGGGGTTCC’ at a distance of 3.6 cM. The selection efficiency of this primer was assessed in a BC3 F1population derived from another cross between a susceptible cultivar IAC 201 and SC09. The marker OPS16 showedefficiency of 86.9%, when six resistant and two susceptible plants were considered as negatives in RAPD analysis.

  17. Flower Initiation, Morphology, and Developmental Stages of Flowering-Fruiting of Mindi (Melia azedarach L

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    Dida Syamsuwida

    2012-04-01

    Full Text Available The study was aimed to determine flower initiation, floral morphology and to observe the stages of flowering and fruit  development of mindi (Melia  azedarch  L within a population  for one period of time 2008–2009.  The methods used were observing directly over the trees and some vegetatives and generatives buds were sampled for dissecting.  The observation revealed that the inflorescence type of mindi was panicle, located at the end of a branch.  The number of flower varied among inflorescences, ranged between 30–80 that bloomed simultaneously.  The flower was hermaphroditic with position of anther was closed to stigma that selfing might be happened.  Usually, the ovary contained 5 ovules that  developed into seeds.  Reproductive cycle was proceeded for 6–7 months within the year, first observation commenced from flower initiation that occur in August, generative buds to flower burst  in September–October.  Early fruits were formed in October–November and fruits reached physiological-maturity in January–February.  Reproductive success was 34%, indicated that the rate of fertilized ovules proportion to be potencially viable seeds were relatively low.Keywords: indian lily, phenology, reproductive biology, reproductive cycle, seed production

  18. Random chromosome elimination in synthetic Triticum-Aegilops amphiploids leads to development of a stable partial amphiploid with high grain micro- and macronutrient content and powdery mildew resistance.

    Science.gov (United States)

    Tiwari, Vijay K; Rawat, Nidhi; Neelam, Kumari; Kumar, Sundip; Randhawa, Gursharn S; Dhaliwal, Harcharan S

    2010-12-01

    Synthetic amphiploids are the immortal sources for studies on crop evolution, genome dissection, and introgression of useful variability from related species. Cytological analysis of synthetic decaploid wheat (Triticum aestivum L.) - Aegilops kotschyi Boiss. amphiploids (AABBDDUkUkSkSk) showed some univalents from the C1 generation onward followed by chromosome elimination. Most of the univalents came to metaphase I plate after the reductional division of paired chromosomes and underwent equational division leading to their elimination through laggards and micronuclei. Substantial variation in the chromosome number of pollen mother cells from different tillers, spikelets, and anthers of some plants also indicated somatic chromosome elimination. Genomic in situ hybridization, fluorescence in situ hybridization, and simple sequence repeat markers analysis of two amphiploids with reduced chromosomes indicated random chromosome elimination of various genomes with higher sensitivity of D followed by the Sk and Uk genomes to elimination, whereas 1D chromosome was preferentially eliminated in both the amphiploids investigated. One of the partial amphiploids, C4 T. aestivum 'Chinese Spring' - Ae. kotschyi 396 (2n = 58), with 34 T. aestivum, 14 Uk, and 10 Sk had stable meiosis and high fertility. The partial amphiploids with white glumes, bold seeds, and tough rachis with high grain macro- and micronutrients and resistance to powdery mildew could be used for T. aestivum biofortification and transfer of powdery mildew resistance.

  19. A New Sythetic Hybrid (A1D5 between Gossypium herbaceum and G. raimondii and Its Morphological, Cytogenetic, Molecular Characterization.

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    Yuxiang Wu

    Full Text Available The diploid species G. herbaceum (A1 and G. raimondii (D5 are the progenitors of allotetraploid cotton, respectively. However, hybrids between G. herbaceum and G. raimondii haven't been reported. In the present study, hybridization between G. herbaceum and G. raimondii was explored. Morphological, cytogenetic and molecular analyses were used to assess the hybridity. The interspecific hybrid plants were successfully obtained. Most of the morphological characteristics of the hybrids were intermediate between G. herbaceum and G. raimondii. However, the color of glands, anther cases, pollen and corolla, and the state of bracteoles in hybrids were associated with the G. herbaceum. The color of staminal columns and filaments in hybrids were associated with G. raimondii. Cytogenetic analysis confirmed abnormal meiotic behavior existed in hybrids. The hybrids couldn't produce boll-set. Simple sequence repeat results found that besides the fragments inherited from the two parents, some novel bands were amplified in hybrids, indicating that potential mutations and chromosomal recombination occurred between parental genomes during hybridization. These results may provide some novel insights in speciation, genome interaction, and evolution of the tetraploid cotton species.

  20. Morpho-anatomical and morphometric studies of the floral structures of the distylous Oldenlandia salzmannii (Rubiaceae

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    Mariela Nuñez Florentin

    Full Text Available ABSTRACT The genus Oldenlandia (Rubiaceae has a conflicting generic delimitation, with representatives that show different floral syndromes. Oldenlandia salzmannii is a marshy herb that is widespread in South America. It is heterostylous, specifically distylous, and self-compatible. Recent molecular phylogenetic studies found that this species forms a clade that is isolated from the remaining described taxa of Oldenlandia. Information about the floral anatomy and reproductive biology of genera in the Spermacoceae tribe, particularly Oldenlandia, is insufficient, especially among the neotropical species. Accordingly, the present study aimed at contributing information on the reproductive biology of Oldenlandia salzmannii by analyzing its floral morpho-anatomy, morphometrics and phenology of both floral morphs. These analyses were conducted with natural, cultivated and fixed material using optical and scanning electron microscopes. Morphologically, the species is typically heterostylous with two floral morphs, long-styled and short-styled, the main difference being the indument of the corolla. The short-styled flowers have larger anthers and pollen grains. Morphometrics show a high degree of herkogamic reciprocity. The mature ovules have a hemitropous position, which is the first record of this position for the Spermacoceae tribe. This study represents the first comprehensive morphological study of Oldenlandia salzmannii.

  1. OsSPL regulates meiotic fate acquisition in rice.

    Science.gov (United States)

    Ren, Lijun; Tang, Ding; Zhao, Tingting; Zhang, Fanfan; Liu, Changzhen; Xue, Zhihui; Shi, Wenqing; Du, Guijie; Shen, Yi; Li, Yafei; Cheng, Zhukuan

    2018-04-01

    In angiosperms, the key step in sexual reproduction is successful acquisition of meiotic fate. However, the molecular mechanism determining meiotic fate remains largely unknown. Here, we report that OsSPOROCYTELESS (OsSPL) is critical for meiotic entry in rice (Oryza sativa). We performed a large-scale genetic screen of rice sterile mutants aimed to identify genes regulating meiotic entry and identified OsSPL using map-based cloning. We showed that meiosis-specific callose deposition, chromatin organization, and centromere-specific histone H3 loading were altered in the cells corresponding to pollen mother cells in Osspl anthers. Global transcriptome analysis showed that the enriched differentially expressed genes in Osspl were mainly related to redox status, meiotic process, and parietal cell development. OsSPL might form homodimers and interact with TEOSINTE BRANCHED1/CYCLOIDEA/PCF (TCP) transcription factor OsTCP5 via the SPL dimerization and TCP interaction domain. OsSPL also interacts with TPL (TOPLESS) corepressors, OsTPL2 and OsTPL3, via the EAR motif. Our results suggest that the OsSPL-mediated signaling pathway plays a crucial role in rice meiotic entry, which appears to be a conserved regulatory mechanism for meiotic fate acquisition in angiosperms. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

  2. Effectiveness of combining resistance to Thielaviopsis basicola and Tomato spotted wilt virus in haploid tobacco genotypes.

    Science.gov (United States)

    Trojak-Goluch, Anna; Laskowska, Dorota; Agacka, Monika; Czarnecka, Diana; Kawka, Magdalena; Czubacka, Anna

    2011-12-01

    Black root rot (BRR) caused by Thielaviopsis basicola as well as Tomato spotted wilt virus (TSWV) are the most serious problems in tobacco growing regions. We crossed the breeding line WGL 3 carrying BRR resistance derived from N.glauca with the line PW-834 the resistance of which to TSWV was transferred from cultivar Polalta. Anthers obtained from F(1) hybrid plants were cultured to induce haploids combining resistance to Th. basicola and TSWV. Flow cytometry analysis revealed 242 haploids and 2 spontaneous doubled haploids among regenerants. All haploids were cloned and then evaluated for BRR as well as TSWV resistance. The presence of pathogens was detected by microscopic evaluation of roots or using DAS-ELISA test. Microscopic assessment showed that, 132 haploids had no symptoms of Th. basicola which, together with the absence of symptoms in the F(1) hybrids, indicated a dominant monogenic mode of inheritance. At the same time only 30 haploids demonstrated resistance to TSWV. SCAR markers associated with TSWV resistance gene detection was applied. The results indicate that small proportion of TSWV-resistant haploids is probably due to the influence of deleterious genes flanking the resistance factor that reduced vitality of gametophytes. Altogether, 24 haploids showed multiple resistance to Th. basicola and TSWV.

  3. New observations on gametogenic development and reproductive experimental tools to support seed yield improvement in cowpea [Vigna unguiculata (L.) Walp].

    Science.gov (United States)

    Salinas-Gamboa, Rigel; Johnson, Susan D; Sánchez-León, Nidia; Koltunow, Anna M G; Vielle-Calzada, Jean-Philippe

    2016-06-01

    Cowpea reproductive tools. Vigna unguiculata L. Walp. (cowpea) is recognized as a major legume food crop in Africa, but seed yields remain low in most varieties adapted to local conditions. The development of hybrid cowpea seed that could be saved after each generation, enabling significant yield increases, will require manipulation of reproductive development from a sexual to an asexual mode. To develop new technologies that could support the biotechnological manipulation of reproductive development in cowpea, we examined gametogenesis and seed formation in two transformable, African-adapted, day-length-insensitive varieties. Here, we show that these two varieties exhibit distinct morphological and phenological traits but share a common developmental sequence in terms of ovule formation and gametogenesis. We present a reproductive calendar that allows prediction of male and female gametogenesis on the basis of sporophytic parameters related to floral bud size and reproductive organ development, determining that gametogenesis occurs more rapidly in the anther than in the ovule. We also show that the mode of megagametogenesis is of the Polygonum-type and not Oenothera-type, as previously reported. Finally, we developed a whole-mount immunolocalization protocol and applied it to detect meiotic proteins in the cowpea megaspore mother cell, opening opportunities for comparing the dynamics of protein localization during male and female meiosis, as well as other reproductive events in this emerging legume model system.

  4. The Formation and Distribution of Ice within Forsythia Flower Buds 1

    Science.gov (United States)

    Ashworth, Edward N.

    1990-01-01

    Differential thermal analysis detected two freezing events when dormant forsythia (Forsythia viridissima Lindl.) flower buds were cooled. The first occurred just below 0°C, and was coincident with the freezing of adjacent woody tissues. The second exotherm appeared as a spike between −10 and −25°C and was correlated with the lethal low temperature. Although this pattern of freezing was similar to that observed in other woody species, differences were noted. Both direct observations of frozen buds and examination of buds freeze-fixed at −5°C demonstrated that ice formed within the developing flowers at temperatures above the second exotherm and lethal temperature. Ice crystals had formed within the peduncle and in the lower portions of the developing flower. Ice also formed within the scales. In forsythia buds, the developing floral organ did not freeze as a unit as noted in other species. Instead the low temperature exotherm appeared to correspond to the lethal freezing of supercooled water within the anthers and portions of the pistil. Images Figure 5 Figure 6 Figure 7 Figure 8 Figure 1 Figure 4 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 PMID:16667340

  5. Does pea lectin expressed transgenically in oilseed rape (Brassica napus) influence honey bee (Apis mellifera) larvae?

    Science.gov (United States)

    Lehrman, Anna

    2007-01-01

    The European honey bee (Apis mellifera) is important both for pollination and for honey production. Pollen is the major protein source for bees, which exposes them directly to changes in pollen quality e.g. through genetic engineering. In order to create a worst case scenario regarding pea lectin (PSL) expressed transgenically in oilseed rape anthers and pollen, the maximum amount of dried pollen that could be mixed in an artificial diet without negatively affecting larval performance (1.5% w/w) was fed to bee larvae. Pollen from two transgenic plant lines expressing PSL up to 1.2% of total soluble protein and pollen from one non-transgenic line was added to the same diet and used as a pollen control. When these three pollen diets and the control diet (without added pollen) were compared, no negative effect from the pollen of the transgenic plants could be detected on larval mortality, weight, or development time. An increased weight and a reduced developmental time were recorded for larvae on all diets containing pollen when compared to the diet without pollen.

  6. Pollination of Greenhouse Tomatoes by the Mexican bumblebee Bombus ephippiatus (Hymenoptera: Apidae

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    Carlos Hernan Vergara

    2012-04-01

    Full Text Available The Mexican native bumblebee Bombus ephippiatus Say was evaluated as a potential pollinator of greenhouse tomatoes (Solanum lycopersicon L.. The experiments were performed at San Andrés Cholula, Puebla, Mexico, from June to December 2004 in two 1 000 m2 greenhouses planted with tomatoes of the cultivar Mallory (Hazera ®. For the experiments, we used two colonies of Bombus ephippiatus, reared in the laboratory from queens captured in the field. Four treatments were applied to 20 study plants: pollination by bumble bees, manual pollination, pollination by mechanical vibration and no pollination (bagged flowers, no vibration. We measured percentage of flowers visited by bumble bees, number of seeds per fruit, maturing time, sugar content, fruit weight and fruit shape. All available flowers were visited by bumblebees, as measured by the degree of anther cone bruising. The number of seeds per fruit was higher for bumble bee-pollinated plants as compared with plants pollinated mechanically or not pollinated and was not significantly different between hand-pollinated and bumble bee-pollinated plants. Maturation time was significantly longer and sugar content, fresh weight and seed count were significantly higher for bumblebee pollinated flowers than for flowers pollinated manually or with no supplemental pollination, but did not differ with flowers pollinated mechanically.

  7. Biotechnological approach in crop improvement by mutation breeding in Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Soeranto, H.; Sobrizal; Sutarto, Ismiyati; Manurung, Simon; Mastrizal [National Nuclear Energy Agency, Center for Research and Development of Isotope and Radiation Technology, Jakarta (Indonesia)

    2002-02-01

    Mutation breeding has become a proven method of improving crop varieties. Most research on plant mutation breeding in Indonesia is carried out at the Center for Research and Development of Isotope and Radiation Technology, National Nuclear Energy Agency (BATAN). Nowadays, a biotechnological approach has been incorporated in some mutation breeding researches in order to improve crop cultivars. This approach is simply based on cellular totipotency, or the ability to regenerate whole, flowering plants from isolated organs, pieces of tissue, individual cells, and protoplasts. Tissue culture technique has bee extensively used for micro propagation of disease-free plants. Other usage of this technique involves in various steps of the breeding process such as germplasm preservation, clonal propagation, and distant hybridization. Mutation breeding combined with tissue culture technique has made a significant contribution in inducing plant genetic variation, by improving selection technology, and by accelerating breeding time as for that by using anther or pollen culture. In Indonesia, research on mutation breeding combined with tissue culture techniques has been practiced in different crop species including rice, ginger, banana, sorghum etc. Specially in rice, a research on identification of DNA markers linked to blast disease resistance is now still progressing. A compiled report from some research activities is presented in this paper. (author)

  8. Efficiency of Buzzing Bees in Fruit Set and Seed Set of Solanum violaceum in Sri Lanka

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    R. W. M. U. M. Wanigasekara

    2012-01-01

    Full Text Available Plant-pollinator interactions are often considered as tightly coevolved, mutualistic relationships. The present study aimed at determining the flower visiting bees of the vegetable crop, Solanum violaceum, and the efficiency of buzz pollination by bees on fruit and seed production in Sri Lanka. Seven bee species: Hoplonomia westwoodi, Amegilla comberi, Patellapis kaluterae, Xylocopa tenuiscapa, Apis dorsata, Trigona iridipennis, and Ceratina hieroglyphica visited the flowers of S. violaceum, and the first four species were buzzing bees. Buzzing bees were the first to visit Solanum flowers and were followed by nonbuzzing bees. Handling time of H. westwoodi and P. kaluterae varied with the availability of pollen in anthers that deplete with the age of flower and stayed longer at new flowers than at old flowers. Handling time of the larger buzzing bee, H. westwoodi, was higher than that of the smaller P. kaluterae. The fruit set, seed set, and seed germinability in flowers visited by buzzing bees were significantly higher than those of the flowers bagged to exclude pollinators.

  9. Genetic control of floral morph in tristylous Pickerelweed (Pontederia cordata L.).

    Science.gov (United States)

    Gettys, Lyn A; Wofford, David S

    2008-01-01

    Pickerelweed (Pontederia cordata L.) is a diploid (2n = 2x = 16) tristylous aquatic perennial. Populations usually contain 3 floral morphs that differ reciprocally in style length and anther height (referred to as the long-, mid-, and short-styled morphs, hereafter L-, M-, and S-morphs). The floral polymorphism promotes disassortative mating among the 3 floral morphs and is maintained in populations by negative frequency-dependent selection. The objective of this study was to determine the number of loci, number of alleles, and gene action controlling floral morph in pickerelweed. Three parental lines (one each of the L-, M-, and S-morph) were used to create S1 and F1 populations. F2 populations were produced through self-pollination of F1 plants. Progeny ratios of S1, F1, and F2 generations revealed that tristyly is controlled by 2 diallelic loci (S and M) with dominant gene action. The S locus is epistatic to the M locus, with the S-morph produced by plants with the dominant S allele (genotype S _ _ _). Plants with recessive alleles at the S locus were either L-morph (ssmm) or M-morph (ssM_). The results of this experiment demonstrate that the inheritance of tristyly in pickerelweed is the same as previously reported for several tristylous species in the Lythraceae and Oxalidaceae.

  10. Isolation, expression analysis and characterization of EgNDL, a NDR-like protein in oil palm (Elaeis guineensis Jacq.

    Directory of Open Access Journals (Sweden)

    Kedsirin Ruttajorn

    2016-06-01

    Full Text Available A novel cDNA of a SF21-like protein or NDR-like protein (EgNDL from Elaeis guineensis Jacq. is 1,044 bp in length and encodes a putative protein with a 347-amino-acid open reading frame. The EgNDL showed 93% identity to the pollenspecific SF21-like protein of Phoenix dactylifera and also showed 79% identity to the NDL protein of Theobroma cacao. Expression analysis of the EgNDL gene in various tissues showed that EgNDL was expressed in the anthers, pistils, mesocarp and leaves. The high expression of EgNDL among three oil palm varieties was significantly expressed in Pisifera (P<0.05, which is commonly used as a male parent in crosses. Computational tools were used to predict the protein and concluded that EgNDL is a putative membrane protein that may function in a signal transduction pathway during pollen development. In this context, knowledge regarding EgNDL and its potential role in plant developmental processes will benefit oil palm breeding programs.

  11. Identification and expression analysis of BoMF25, a novel polygalacturonase gene involved in pollen development of Brassica oleracea.

    Science.gov (United States)

    Lyu, Meiling; Liang, Ying; Yu, Youjian; Ma, Zhiming; Song, Limin; Yue, Xiaoyan; Cao, Jiashu

    2015-06-01

    BoMF25 acts on pollen wall. Polygalacturonase (PG) is a pectin-digesting enzyme involved in numerous plant developmental processes and is described to be of critical importance for pollen wall development. In the present study, a PG gene, BoMF25, was isolated from Brassica oleracea. BoMF25 is the homologous gene of At4g35670, a PG gene in Arabidopsis thaliana with a high expression level at the tricellular pollen stage. Collinear analysis revealed that the orthologous gene of BoMF25 in Brassica campestris (syn. B. rapa) genome was probably lost because of genome deletion and reshuffling. Sequence analysis indicated that BoMF25 contained four classical conserved domains (I, II, III, and IV) of PG protein. Homology and phylogenetic analyses showed that BoMF25 was clustered in Clade F. The putative promoter sequence, containing classical cis-acting elements and pollen-specific motifs, could drive green fluorescence protein expression in onion epidermal cells. Quantitative RT-PCR analysis suggested that BoMF25 was mainly expressed in the anther at the late stage of pollen development. In situ hybridization analysis also indicated that the strong and specific expression signal of BoMF25 existed in pollen grains at the mature pollen stage. Subcellular localization showed that the fluorescence signal was observed in the cell wall of onion epidermal cells, which suggested that BoMF25 may be a secreted protein localized in the pollen wall.

  12. Expression and correlation of matrix metalloproteinase-7 and interleukin-15 in human osteoarthritis.

    Science.gov (United States)

    Tao, Yulei; Qiu, Xianxing; Xu, Changbo; Sun, Bo; Shi, Changxiu

    2015-01-01

    To investigate the expression and correlation of matrix metalloproteinase (MMP)-7 and interleukin (IL)-15 in human osteoarthritis (OA). From October 2013 to December 2014, 30 patients with OA were enrolled. In addition, anther 30 patients with simple meniscus injury were collected as a control group. There were no significant differences in age and gender between the two groups. Articular cartilage tissue was obtained from both OA patients and control group patients. Protein, mRNA, and serum expression levels of MMP-7 and IL-15 in the both two groups were determined by immunohistochemical (IHC), in situ hybridization, and enzyme-linked immunosorbent assay (ELISA) assay, respectively. Additionally, correlation between MMP-7 and IL-15 expression level in cartilage tissue and serum was assessed using Pearson correlation analysis. Protein, mRNA, and serum expression levels of MMP-7 and IL-15 in patients with OA were all significantly increased in OA patients compared with the control group. Besides, there were strong positive relationships between articular MMP-7 level and serum MMP-7 level (R(2) = 0.573, P = 0.018), between articular IL-15 level and serum IL-15 level (R(2) = 0.861, P = 0.023), and between serum IL-15 level and serum MMP-7 level (R(2) = 0.602, P = 0.012). These results suggest that MMP-7 and IL-15 might play important roles in the pathogenesis of OA, and IL-15 and MMP-7 has positive correlation in OA.

  13. First evidence of putrescine involvement in mitigating the floral malformation in mangoes: a scanning electron microscope study.

    Science.gov (United States)

    Singh, Archana; Ansari, Mohammad W; Rani, Varsha; Singh, C P; Shukla, Alok; Pant, Ramesh C; Tuteja, Narendra; Bains, Gurdeep

    2014-09-01

    Floral malformation is the most destructive disease in mangoes. To date, the etiology of this disease has not been resolved. There are indications that stress-stimulated ethylene production might be responsible for the disease. Putrescine mediates various physiological processes for normal functioning and cellular metabolism. Here, the effect of putrescine in concentration ranging from 10(-1) to 10(-3) M was evaluated on disease incidence during mango flowering seasons of 2012 and 2013. In a scanning electron microscopy (SEM) study, putrescine (10(-2) M)-treated malformed floral buds bloomed into opened flowers with separated sepals and/or petals like healthy, whereas the untreated (control) malformed buds remained deformed. Further, malformed flowers recovered upon putrescine treatment, displaying clearly bilobed anthers, enclosing a large number of normal pollen grains and functional ovary with broad stigmatic surface as compared to control. The present findings provide the first report to demonstrate the role of putrescine in reducing various adverse effects of stress ethylene via decelerating the higher pace of its biosynthesis. It stabilizes the normal morphology, development, and functions of malformed reproductive organs to facilitate successful pollination, fertilization, and, thereby, fruit set in mango flowers. However, putrescine-ethylene-mediated cell signaling network, involving various genes to trigger the response, which regulates a wide range of developmental and physiological processes leading to normal cell physiology, needs to be investigated further.

  14. Tissue culture characteristics of maize (Zea mays L.) haploid coleoptile sections.

    Science.gov (United States)

    Jiang, L; Jing, G X; Li, X Y; Wang, X Q; Xing, Z; Deng, P K; Zhao, R G

    2015-12-08

    Doubled haploid (DH) technology, which is used for rapidly purifying genetic resources, is a key technology in modern maize breeding. The present study evaluated the tissue culture characteristics of maize haploid coleoptile sections, in order to provide a new way of haploid doubling. With 20 combinations of haploid coleoptile sections, obtained by hybridization within Reid, Tangsipingtou, and Term-tropical groups, as explants, we analyzed the induction and differentiation rate of callus, observed the number of root tip chromosomes in regenerated plants, and analyzed the pollen fertility. In addition, we used 47 SSR markers to analyze the genotypes of regenerated plants. The Reid and Tangsipingtou groups had significantly higher induction rates of haploid coleoptile callus compared to the Term-tropical group. Fifteen haploid plants were obtained which had 10 chromosomes in the root tips as assessed by I-KI staining. It was also noticed that the pollen of pollinated anthers were partially fertile. The haploid plants had genetic stability and showed no variation. The Reid and Tangsipingtou groups had good culture characteristics of haploid coleoptile sections, while the Term-tropical group had poor culture characteristics. Genotypes of haploid plants generated by tissue culture were evidenced to come from recombinant types of parents. Thus, this study established a tissue culture system of maize haploid coleoptile.

  15. Gene Coexpression Analysis Reveals Complex Metabolism of the Monoterpene Alcohol Linalool in Arabidopsis Flowers[W][OPEN

    Science.gov (United States)

    Ginglinger, Jean-François; Boachon, Benoit; Höfer, René; Paetz, Christian; Köllner, Tobias G.; Miesch, Laurence; Lugan, Raphael; Baltenweck, Raymonde; Mutterer, Jérôme; Ullmann, Pascaline; Beran, Franziska; Claudel, Patricia; Verstappen, Francel; Fischer, Marc J.C.; Karst, Francis; Bouwmeester, Harro; Miesch, Michel; Schneider, Bernd; Gershenzon, Jonathan; Ehlting, Jürgen; Werck-Reichhart, Danièle

    2013-01-01

    The cytochrome P450 family encompasses the largest family of enzymes in plant metabolism, and the functions of many of its members in Arabidopsis thaliana are still unknown. Gene coexpression analysis pointed to two P450s that were coexpressed with two monoterpene synthases in flowers and were thus predicted to be involved in monoterpenoid metabolism. We show that all four selected genes, the two terpene synthases (TPS10 and TPS14) and the two cytochrome P450s (CYP71B31 and CYP76C3), are simultaneously expressed at anthesis, mainly in upper anther filaments and in petals. Upon transient expression in Nicotiana benthamiana, the TPS enzymes colocalize in vesicular structures associated with the plastid surface, whereas the P450 proteins were detected in the endoplasmic reticulum. Whether they were expressed in Saccharomyces cerevisiae or in N. benthamiana, the TPS enzymes formed two different enantiomers of linalool: (−)-(R)-linalool for TPS10 and (+)-(S)-linalool for TPS14. Both P450 enzymes metabolize the two linalool enantiomers to form different but overlapping sets of hydroxylated or epoxidized products. These oxygenated products are not emitted into the floral headspace, but accumulate in floral tissues as further converted or conjugated metabolites. This work reveals complex linalool metabolism in Arabidopsis flowers, the ecological role of which remains to be determined. PMID:24285789

  16. Effect of pollen irradiation on hybridization of wheat and Eltrigia intermedia and their embryo development

    International Nuclear Information System (INIS)

    Li Guiying; Wang Linqing; Shi Jinguo

    2005-01-01

    Spikes of Eltrigia intermedia were radiated with 5-100 Gy γ-ray during anthesis, and then their pollens were collected to pollinate to the common wheat 'J-11' and 'Chinese Spring'. The effects of pollen irradiation on the seed setting, embryo development, embryo culture and plantlet rate were studied. The results showed that low dose (5-9 Gy) of irradiation enhanced the seed setting for Chinese spring x E. intermedia, but no such effect for J-11xE. intermedia. Irradiation with all doses damaged embryo development, percentage of seeds with embryos; rate of immature hybrid embryos developing into plantlets decreases with the increased doses. Percentage of seeds with abnormal embryos increased significantly with the doses. 12.9%-14.5% of embryos could develop into plants in 30 Gy treatment, which seldom occur to wheat. Embryos in 50 Gy-100 Gy treatment were affected so serious that even none of them could develop into plants in vitro culture. It may be an effective approach to obtaining more mutants and enhancing induced mutation breeding by using combination of pollen irradiation, immature embryo rescue and anther culture of the resultant progenies. (authors)

  17. The effects of gamma-ray irradiation to strawberry (Fragaria x ananassa Duch.) calli on shoot regeneration, achene formation and morphological variations of regenerants

    Energy Technology Data Exchange (ETDEWEB)

    Kasumi, Masakazu [Plant Biotechnology Inst., Ibaraki Agricultural Center, Iwama, Ibaraki (Japan)

    2002-05-01

    Strawberry (Fragaria x ananassa 'Nyoho') calli, derived from anthers, were irradiated with gamma -ray at dosages from 100 to 1,600 Gy (10 Gy {center_dot} hr{sup -}1) and their effects on callus growth, plant regeneration, and somaclonal variation were analyzed. The growth of callus and percentage of plant regeneration from the callus were reduced slightly at dosages less than 200 Gy, moderately at 400 Gy, and markedly above 800 Gy. Fruit growth associated with seed fertility (>50 % ) was morphologically normal at less than 100 Gy, whereas achene formation was significantly inhibited above 200 Gy. The percentages of morphological variation in regenerants formed from the irradiated callus were:13.7 (no irradiation), 18.6 (100 Gy), 66.0 (200 Gy), 75.7 (400 Gy), and 97.0 (800 Gy). Furthermore, higher dosages yielded wider variations, e.g., thick and small leaf, light leaf color, white flesh, and long fruit. In some regenerants, more than one morphological aberrations developed, some of which were transmissible to daughter plants. These results revealed that the irradiating strawberry callus with gamma - ray resulted in a higher degree and wider spectrum of somaclonal variation than did simple callus culture. (author)

  18. Original Article. Effects of loose kernel smut caused by Sporisorium cruentum onrhizomes of Sorghum halepense

    Directory of Open Access Journals (Sweden)

    Gassó Marta Monica Astiz

    2016-08-01

    Full Text Available The effect of loose kernel smut fungus Sporisorium cruentum on Sorghum halepense (Johnson grass was investigated in vitro and in greenhouse experiments. Smut infection induced a decrease in the dry matter of rhizomes and aerial vegetative parts of the plants evaluated. Moreover, the diseased plants showed a lower height than controls. The infection resulted in multiple smutted buds that caused small panicles infected with the fungus. In addition, changes were observed in the structural morphology of the host. Leaf tissue sections showed hyphae degrading chloroplasts and vascular bundles colonized by the fungus. Subsequently, cells collapsed and widespread necrosis was observed as a symptom of the disease. The pathogen did not colonize the gynoecium of Sorghum plants until the tassel was fully developed. The sporulation process of the fungus led to a total disintegration of anthers and tissues. When panicles were inspected before emergence, fungal hyphae were observed on floral primord. Histological sections of panicles showed fungal hyphae located in the parenchyma tissue and the nodal area. Infection occurred in the floral primordium before the tassel had fully developed and emerged from the flag leaf. Grains were replaced by sori surrounded by a thin membrane that usually was broken before or after the emergence of the panicle. The results, together with the significant decrease of the dry matter of rhizomes and seeds of S. halepense, suggest that S. cruentum could be considered as a potential biocontrol agent in the integrated management of this weed.

  19. 'Gornooriahovska Kapia F1' - A new hybrid pepper variety based on radiation induced male sterility

    International Nuclear Information System (INIS)

    Daskalov, S.

    2001-01-01

    The female parent line 'Zlaten medal ms-8' was obtained by Daskalov as a gamma rays induced mutant of pepper (Capsicum annum L.). Dry seeds of the initial variety 'Zlaten medal' were irradiated with 135 Gy gamma rays and after screening of a large M 2 population (57,000 plants) 3 male sterile mutants were obtained. After an allelic test the genes responsible for male sterility were denoted as ms-6, ms-7, and ms-8. After many years of testing various male sterility sources the gene ms-8 proved to be the most suitable for hybrid seed production because it determines 100% male sterility, independent of the climatic condition or the genotype. The mutation causes the highest reduction of anthers, which allows easy distinction between male sterile and fertile flowers. The development of the mutant male sterile line Zlaten medal ms-8 is a good example of how mutation techniques can be very useful for adding or changing only one trait without altering the basic genotype

  20. Chromatin dynamics in Pollen Mother Cells underpin a common scenario at the somatic-to-reproductive fate transition of both the male and female lineages in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Wenjing eShe

    2015-04-01

    Full Text Available Unlike animals, where the germline is established early during embryogenesis, plants set aside their reproductive lineage late in development in dedicated floral organs. The specification of pollen mother cells (PMCs committed to meiosis takes place in the sporogenous tissue in anther locules and marks the somatic-to-reproductive cell fate transition towards the male reproductive lineage. Here we show that Arabidopsis PMCs differentiation is accompanied by large-scale changes in chromatin organization. This is characterized by significant increase in nuclear volume, chromatin decondensation, reduction in heterochromatin, eviction of linker histones and the H2AZ histone variant. These structural alterations are accompanied by dramatic, quantitative changes in histone modifications levels compared to that of surrounding somatic cells that do not share a sporogenic fate. All these changes are highly reminiscent of those we have formerly described in female megaspore mother cells (MMCs. This indicates that chromatin reprogramming is a common underlying scenario in the somatic-to-reproductive cell fate transition in both male and female lineages.

  1. Antagonistic action of Bacillus subtilis strain SG6 on Fusarium graminearum.

    Directory of Open Access Journals (Sweden)

    Yueju Zhao

    Full Text Available Fusarium graminearum causes Fusarium head blight (FHB, a devastating disease that leads to extensive yield and quality loss of wheat and barley. Bacteria isolated from wheat kernels and plant anthers were screened for antagonistic activity against F. graminearum. Based on its in vitro effectiveness, strain SG6 was selected for characterization and identified as Bacillus subtilis. B. subtilis SG6 exhibited a high antifungal effect on the mycelium growth, sporulation and DON production of F. graminearum with the inhibition rate of 87.9%, 95.6% and 100%, respectively. In order to gain insight into biological control effect in situ, we applied B. subtilis SG6 at anthesis through the soft dough stage of kernel development in field test. It was revealed that B. subtilis SG6 significantly reduced disease incidence (DI, FHB index and DON (P ≤ 0.05. Further, ultrastructural examination shows that B. subtilis SG6 strain induced stripping of F. graminearum hyphal surface by destroying the cellular structure. When hypha cell wall was damaged, the organelles and cytoplasm inside cell would exude, leading to cell death. The antifungal activity of SG6 could be associated with the coproduction of chitinase, fengycins and surfactins.

  2. The impact of foliar boron sprays on reproductive biology and seed quality of black gram.

    Science.gov (United States)

    Pandey, Nalini; Gupta, Bhavana

    2013-01-01

    An experiment was conducted under glass house condition to study the effect of foliar application of boron (B) on reproductive biology and seed quality of black gram (Vigna mungo). Black gram (V. mungo L. var. DPU-88-31) was grown under controlled sand culture condition at deficient and sufficient B levels. After 32 days of sowing B deficient plants were sprayed with three concentrations of B (0.05%, 0.1% and 0.2% borax) at three different stages of reproductive development, i.e. prior to flowering, initiation of bud formation and after bud formation. Deficient B supply decreased the anther and pollen size, pollen tube growth, pollen viability as well as stigmatic receptivity which were increased by foliar B application. Foliar spray at all the three concentrations and at all stages increased the yield parameters like number of pods, pod size and number of seeds formed per plant. Foliar B application also improved the seed yield and seed quality in terms of storage seed proteins (albumin, globulin, glutenin and prolamin) and carbohydrates (sugars and starch) in black gram. The foliar application of B in appropriate doses (particularly 0.1%) after bud formation made quantitative and qualitative improvement in seed yield of black gram by supplementing additional/critical B requirements for reproductive development. Copyright © 2012 Elsevier GmbH. All rights reserved.

  3. Germination of the seeds and cytogenetic analysis in two species of palms

    Directory of Open Access Journals (Sweden)

    Alice Battistin

    2012-10-01

    Full Text Available Euterpe edulis and Archontophoenix alexandrae are palm trees used for ornamentation purpose and palm heart extraction. Seed germination and VGI, mitotic and meiotic chromosome behavior and quantification of pollen were assessed. For each species in each location and in each substracts, 60 seeds were used. Mitotic chromosome analyses and identification of differential nucleoli were made in meristem zone of primary root. Giemsa 2% (m/v and AgNO3 50% (m/v were used as dyes, respectively. Chromosomes analysis in microsporogenesis and pollen viability were made on anthers of buds and stained with carmine propionic 2% (m/v. The greatest index of germination and VGI of the seeds, in two species, were observed in samples from Maquiné in a substract containing vermiculite. A. alexandrae is a diploid with 2n=2x=32 chromosomes with karyotype m+12sm+4st+2t. E. edulis is a diploid with 2n=2x=36 chromosomes with karyotype 16m + 12sm + 8t. Both have a submetacentric pair of chromosomes with intermediate secondary constriction containing nucleoli with active ribosome genes. In these two species microsporogenesis and pollen analyses showed high percentage of normal cells at all stages of meiosis I and II resulting a high meiotic index (normal tetrads and pollen viability, indicating that in these species the genes are expressed normally in environmental conditions in which they live and do not present problems in the formation of male reproductive cells.

  4. Transcriptome sequencing and de novo analysis of a cytoplasmic male sterile line and its near-isogenic restorer line in chili pepper (Capsicum annuum L..

    Directory of Open Access Journals (Sweden)

    Chen Liu

    Full Text Available BACKGROUND: The use of cytoplasmic male sterility (CMS in F1 hybrid seed production of chili pepper is increasingly popular. However, the molecular mechanisms of cytoplasmic male sterility and fertility restoration remain poorly understood due to limited transcriptomic and genomic data. Therefore, we analyzed the difference between a CMS line 121A and its near-isogenic restorer line 121C in transcriptome level using next generation sequencing technology (NGS, aiming to find out critical genes and pathways associated with the male sterility. RESULTS: We generated approximately 53 million sequencing reads and assembled de novo, yielding 85,144 high quality unigenes with an average length of 643 bp. Among these unigenes, 27,191 were identified as putative homologs of annotated sequences in the public protein databases, 4,326 and 7,061 unigenes were found to be highly abundant in lines 121A and 121C, respectively. Many of the differentially expressed unigenes represent a set of potential candidate genes associated with the formation or abortion of pollen. CONCLUSIONS: Our study profiled anther transcriptomes of a chili pepper CMS line and its restorer line. The results shed the lights on the occurrence and recovery of the disturbances in nuclear-mitochondrial interaction and provide clues for further investigations.

  5. Wind gusts and plant aeroelasticity effects on the aerodynamics of pollen shedding: a hypothetical turbulence-initiated wind-pollination mechanism.

    Science.gov (United States)

    Urzay, Javier; Llewellyn Smith, Stefan G; Thompson, Elinor; Glover, Beverley J

    2009-08-21

    Plant reproduction depends on pollen dispersal. For anemophilous (wind-pollinated) species, such as grasses and many trees, shedding pollen from the anther must be accomplished by physical mechanisms. The unknown nature of this process has led to its description as the 'paradox of pollen liberation'. A simple scaling analysis, supported by experimental measurements on typical wind-pollinated plant species, is used to estimate the suitability of previous resolutions of this paradox based on wind-gust aerodynamic models of fungal-spore liberation. According to this scaling analysis, the steady Stokes drag force is found to be large enough to liberate anemophilous pollen grains, and unsteady boundary-layer forces produced by wind gusts are found to be mostly ineffective since the ratio of the characteristic viscous time scale to the inertial time scale of acceleration of the wind stream is a small parameter for typical anemophilous species. A hypothetical model of a stochastic aeroelastic mechanism, initiated by the atmospheric turbulence typical of the micrometeorological conditions in the vicinity of the plant, is proposed to contribute to wind pollination.

  6. Trait correlates and functional significance of heteranthery in flowering plants.

    Science.gov (United States)

    Vallejo-Marín, Mario; Da Silva, Elizabeth M; Sargent, Risa D; Barrett, Spencer C H

    2010-10-01

    • Flowering plants display extraordinary diversity in the morphology of male sexual organs, yet the functional significance of this variation is not well understood. Here, we conducted a comparative analysis of floral correlates of heteranthery - the morphological and functional differentiation of anthers within flowers - among angiosperm families to identify traits associated with this condition. • We performed a phylogenetic analysis of correlated evolution between heteranthery and several floral traits commonly reported from heterantherous taxa. In addition, we quantified the effect of phylogenetic uncertainty in the observed patterns of correlated evolution by comparing trees in which polytomous branches were randomly resolved. • Heteranthery is reported from 12 angiosperm orders and is phylogenetically associated with the absence of floral nectaries, buzz-pollination and enantiostyly (mirror-image flowers). These associations are robust to particularities of the underlying phylogenetic hypothesis. • Heteranthery has probably evolved as a result of pollinator-mediated selection and appears to function to reduce the conflict of relying on pollen both as food to attract pollinators and as the agent of male gamete transfer. The relative scarcity of heteranthery among angiosperm families suggests that the conditions permitting its evolution are not easily met despite the abundance of pollen-collecting bees and nectarless flowers. © The Authors (2010). Journal compilation © New Phytologist Trust (2010).

  7. Reproductive biology of the biofuel plant Jatropha curcas in its center of origin

    Directory of Open Access Journals (Sweden)

    Manuel Rincón-Rabanales

    2016-03-01

    Full Text Available In this work, we studied the main characteristics of flowering, reproductive system and diversity of pollinators for the biofuel plant Jatropha curcas (L. in a site of tropical southeastern Mexico, within its center of origin. The plants were monoecious with inflorescences of unisexual flowers. The male flowers produced from 3062–5016 pollen grains (266–647 per anther. The plants produced fruits with both geitonogamy and xenogamy, although insect pollination significantly increased the number and quality of fruits. A high diversity of flower visiting insects (36 species was found, of which nine were classified as efficient pollinators. The native stingless bees Scaptotrigona mexicana (Guérin-Meneville and Trigona (Tetragonisca angustula (Latreille were the most frequent visitors and their presence coincided with the hours when the stigma was receptive. It is noteworthy that the female flowers open before the male flowers, favoring xenogamy, which may explain the high genetic variability reported in J. curcas for this region of the world.

  8. Biotechnology-assisted breeding techniques implementation for rice improvement in Uruguay

    International Nuclear Information System (INIS)

    Blanco, P.; Capdevielle, F.; Avila, S.; Perez, F.; Branda, A.; Castillo, A.; Stoll, M.

    2001-01-01

    Mutagenic treatment was highly effective in reducing plant height and growth duration in the parent variety EEA-404. Important variation was also observed in grain and leaf pubescence and in grain shape. Several M 4 lines with desirable plant type and grain shape were selected for yield testing. Aggregated sheath spot (ASS) - Rhizoctonia oryzae sativae - disease pressure on M 3 and M 4 lines from INIA Tacuari was not sufficient to allow selection for this character. However, important variability in resistance to the physiological disorder Straighthead was observed among the lines. The regeneration percentage obtained with the methodology of anther culture facilitated application of this technique in a larger number of crosses. Some of the doubled haploid (DH) lines from resistant/susceptible crosses showed good yield potential and milling quality, and low incidence of stem diseases. Sequential Bulked Typing may provide an alternative to individual typing for a large number of markers, improving DNA pooling techniques based on phenotypic evaluations of quantitative traits. (author)

  9. The exploit of cereal embryo structure for productive reasons by in vitro techniques

    Science.gov (United States)

    Savaskan, C.

    2017-07-01

    There are two main sides of our works exploiting embryo structure in durum wheat and some other cereals. First is haploid (or doubled haploid) embryo production using anther or microspore culture or intergeneric crosses, to ameliorate desirable characters genetically homozygote. Secondly, to develope convenient embryo culture technique in order to be stored and cultivated longer time of genotypes without being alien pollination etc. in field conditions. For that reason, two different auxin and also their combination with kinetin were used for mature embryos of wheat genotypes (hexaploid and tetraploid), to understand efficient dose for calli production and plant regeneration in plant tissue culture. Modified MS media were used adding a single dose of arabinogalactan protein (AGP) and without adding for regeneration. In further step of this study, most efficient auxin+kinetin combination which is determined previous research, it was used in the same modified MS medium to produce calli production and plant regeneration in three different genotypes (hexaploid and tetraploid wheat and diploid barley). Data were calculated in five different developmental stages of treatments. All statistical analysis of data were performed and means were compared with Duncan's test. Genetics and morphological effects of AGP on genotypes were discussed with the results of variance analysis. Simple correlation coefficient (r) was calculated base on the main values of replications.

  10. The role of activated charcoal in plant tissue culture.

    Science.gov (United States)

    Thomas, T Dennis

    2008-01-01

    Activated charcoal has a very fine network of pores with large inner surface area on which many substances can be adsorbed. Activated charcoal is often used in tissue culture to improve cell growth and development. It plays a critical role in micropropagation, orchid seed germination, somatic embryogenesis, anther culture, synthetic seed production, protoplast culture, rooting, stem elongation, bulb formation etc. The promotary effects of AC on morphogenesis may be mainly due to its irreversible adsorption of inhibitory compounds in the culture medium and substancially decreasing the toxic metabolites, phenolic exudation and brown exudate accumulation. In addition to this activated charcoal is involved in a number of stimulatory and inhibitory activities including the release of substances naturally present in AC which promote growth, alteration and darkening of culture media, and adsorption of vitamins, metal ions and plant growth regulators, including abscisic acid and gaseous ethylene. The effect of AC on growth regulator uptake is still unclear but some workers believe that AC may gradually release certain adsorbed products, such as nutrients and growth regulators which become available to plants. This review focuses on the various roles of activated charcoal in plant tissue culture and the recent developments in this area.

  11. Abnormal development of tapetum and microspores induced by chemical hybridization agent SQ-1 in wheat.

    Directory of Open Access Journals (Sweden)

    Shuping Wang

    Full Text Available Chemical hybridization agent (CHA-induced male sterility is an important tool in crop heterosis. To demonstrate that CHA-SQ-1-induced male sterility is associated with abnormal tapetal and microspore development, the cytology of CHA-SQ-1-treated plant anthers at various developmental stages was studied by light microscopy, scanning and transmission electron microscopy, in situ terminal deoxynucleotidyl transferasemediated dUTP nick end-labelling (TUNEL assay and DAPI staining. The results indicated that the SQ-1-treated plants underwent premature tapetal programmed cell death (PCD, which was initiated at the early-uninucleate stage of microspore development and continued until the tapetal cells were completely degraded; the process of microspore development was then blocked. Microspores with low-viability (fluorescein diacetate staining were aborted. The study suggests that premature tapetal PCD is the main cause of pollen abortion. Furthermore, it determines the starting period and a key factor in CHA-SQ-1-induced male sterility at the cell level, and provides cytological evidence to further study the mechanism between PCD and male sterility.

  12. Mitochondrial Dysfunction Causes Oxidative Stress and Tapetal Apoptosis in Chemical Hybridization Reagent-Induced Male Sterility in Wheat

    Directory of Open Access Journals (Sweden)

    Shuping Wang

    2018-01-01

    Full Text Available Male sterility in plants has been strongly linked to mitochondrial dysfunction. Chemical hybridization agent (CHA-induced male sterility is an important tool in crop heterosis. Therefore, it is important to better understand the relationship between mitochondria and CHA-induced male sterility in wheat. This study reports on the impairment of mitochondrial function duo to CHA-SQ-1, which occurs by decreasing cytochrome oxidase and adenosine triphosphate synthase protein levels and theirs activities, respiratory rate, and in turn results in the inhibition of the mitochondrial electron transport chain (ETC, excessive production of reactive oxygen species (ROS and disruption of the alternative oxidase pathway. Subsequently, excessive ROS combined with MnSOD defects results in damage to the mitochondrial membrane, followed by ROS release into the cytoplasm. The microspores underwent severe oxidative stress during pollen development. Furthermore, chronic oxidative stress, together with the overexpression of type II metacaspase, triggered premature tapetal apoptosis, which resulted in pollen abortion. Accordingly, we propose a metabolic pathway for mitochondrial-mediated male sterility in wheat, which provides information on the molecular events underlying CHA-SQ-1-induced abortion of anthers and may serve as an additional guide to the practical application of hybrid breeding.

  13. Expression and regulation of pear 1-aminocyclopropane-1-carboxylic acid synthase gene (PpACS1a) during fruit ripening, under salicylic acid and indole-3-acetic acid treatment, and in diseased fruit.

    Science.gov (United States)

    Shi, Hai-Yan; Zhang, Yu-Xing

    2014-06-01

    In plants, the level of ethylene is determined by the activity of the key enzyme 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS). A gene encoding an ACC synthase protein was isolated from pear (Pyrus pyrifolia). This gene designated PpACS1a (GenBank accession no. KC632526) was 1488 bp in length with an open reading frame (ORF) encoding a protein of 495 amino acids that shared high similarity with other pear ACC synthase proteins. The PpACS1a was grouped into type-1 subfamily of plant ACS based on its conserved domain and phylogenetic status. Real-time quantitative PCR indicated that PpACS1a was differentially expressed in pear tissues and predominantly expressed in anthers. The expression signal of PpACS1a was also detected in fruit and leaves, but no signal was detected in shoots and petals. Furthermore, the PpACS1a expression was regulated during fruit ripening. In addition, the PpACS1a gene expression was regulated by salicylic acid (SA) and indole-3-acetic acid (IAA) in fruit. Moreover, the expression of the PpACS1a was up-regulated in diseased pear fruit. These results indicated that PpACS1a might be involved in fruit ripening and response to SA, IAA and disease.

  14. Mutation in SUMO E3 ligase, SIZ1, disrupts the mature female gametophyte in Arabidopsis

    KAUST Repository

    Ling, Yu

    2012-01-09

    Female gametophyte is the multicellular haploid structure that can produce embryo and endosperm after fertilization, which has become an attractive model system for investigating molecular mechanisms in nuclei migration, cell specification, cell-to-cell communication and many other processes. Previous reports found that the small ubiquitin-like modifier (SUMO) E3 ligase, SIZ1, participated in many processes depending on particular target substrates and suppression of salicylic acid (SA) accumulation. Here, we report that SIZ1 mediates the reproductive process. SIZ1 showed enhanced expression in female organs, but was not detected in the anther or pollen. A defect in the siz1-2 maternal source resulted in reduced seed-set regardless of high SA concentration within the plant. Moreover, aniline blue staining and scanning electron microscopy revealed that funicular and micropylar pollen tube guidance was arrested in siz1-2 plants. Some of the embryo sacs of ovules in siz1-2 were also disrupted quickly after stage FG7. There was no significant affects of the siz1-2 mutation on expression of genes involved in female gametophyte development- or pollen tube guidance in ovaries. Together, our results suggest that SIZ1 sustains the stability and normal function of the mature female gametophyte which is necessary for pollen tube guidance. © 2012 Ling et al.

  15. Stage-related expression of mRNAs during pollen development in lily and tobacco.

    Science.gov (United States)

    Schrauwen, J A; de Groot, P F; van Herpen, M M; van der Lee, T; Reynen, W H; Weterings, K A; Wullems, G J

    1990-09-01

    Homogeneous populations of developing microspores and pollen from anthers of lily (Lilium longiflorum Thumb.) and tobacco (Nicotiana tabacum L.) show a continuous production of biomass, reaching a maximum in young pollen. The rate of RNA synthesis was 460 fg · h(-1) in young binucleate cells, 138 fg · h(-1) in late binucleate cells and 56 fg · h(-1) in microspores. The mRNA population in developing pollen can be separated into three groups. In the first group, certain types of mRNAs are present at a constant level during all stages of development. A second group is characteristic of young pollen and increases quantitatively until anthesis. A third group is seen transiently; to this belong mRNAs present only before mitosis or at a distinct cell stage after mitosis. Some of the translation products of this latter group of mRNAs showed similarities between lily and tobacco on two-dimensional gels in respect of molecular weight and isolectric point, indicating that those mRNAs and proteins play a role in the regulation of pollen development.

  16. Bacillus velezensis RC 218 as a biocontrol agent to reduce Fusarium head blight and deoxynivalenol accumulation: Genome sequencing and secondary metabolite cluster profiles.

    Science.gov (United States)

    Palazzini, Juan M; Dunlap, Christopher A; Bowman, Michael J; Chulze, Sofía N

    2016-11-01

    Bacillus subtilis RC 218 was originally isolated from wheat anthers as a potential antagonist of Fusarium graminearum, the causal agent of Fusarium head blight (FHB). It was demonstrated to have antagonist activity against the plant pathogen under in vitro and greenhouse assays. The current study extends characterizing B. subtilis RC 218 with a field study and genome sequencing. The field study demonstrated that B. subtilis RC 218 could reduce disease severity and the associated mycotoxin (deoxynivalenol) accumulation, under field conditions. The genome sequencing allowed us to accurately determine the taxonomy of the strain using a phylogenomic approach, which places it in the Bacillus velezensis clade. In addition, the draft genome allowed us to use bioinformatics to mine the genome for potential metabolites. The genome mining allowed us to identify 9 active secondary metabolites conserved by all B. velezensis strains and one additional secondary metabolite, the lantibiotic ericin, which is unique to this strain. This study represents the first confirmed production of ericin by a B. velezensis strain. The genome also allowed us to do a comparative genomics with its closest relatives and compare the secondary metabolite production of the publically available B. velezensis genomes. The results showed that the diversity in secondary metabolites of strains in the B. velezensis clade is driven by strains making different antibacterials. Copyright © 2016 Elsevier GmbH. All rights reserved.

  17. Comparative Analysis of the Cytology and Transcriptomes of the Cytoplasmic Male Sterility Line H276A and Its Maintainer Line H276B of Cotton (Gossypium barbadense L.

    Directory of Open Access Journals (Sweden)

    Xiangjun Kong

    2017-10-01

    Full Text Available In this study, the tetrad stage of microspore development in a new cotton (Gossypium barbadense L. cytoplasmic male sterility (CMS line, H276A, was identified using paraffin sections at the abortion stage. To explore the molecular mechanism underlying CMS in cotton, a comparative transcriptome analysis between the CMS line H276A and its maintainer line H276B at the tetrad stage was conducted using an Illumina HiSeq 4000 platform. The comparison of H276A with H276B revealed a total of 64,675 genes, which consisted of 59,255 known and 5420 novel genes. An analysis of the two libraries with a given threshold yielded a total of 3603 differentially expressed genes (DEGs, which included 1363 up- and 2240 down-regulated genes. Gene Ontology (GO annotation showed that 2171 DEGs were distributed into 38 categories, and a Kyoto Encyclopedia of Genes and Genomes (KEGG analysis showed that 2683 DEGs were classified into 127 groups. Thirteen DEGs were randomly selected and detected by quantitative reverse-transcribed PCR (qRT-PCR, and the results indicated that the transcriptome sequencing results were reliable. The bioinformatic analysis results in conjunction with previously reported data revealed key DEGs that might be associated with the male sterility features of H276A. Our results provide a comprehensive foundation for understanding anther development and will accelerate the study of the molecular mechanisms of CMS in cotton.

  18. The Cysteine Protease CEP1, a Key Executor Involved in Tapetal Programmed Cell Death, Regulates Pollen Development in Arabidopsis[W][OPEN

    Science.gov (United States)

    Zhang, Dandan; Liu, Di; Lv, Xiaomeng; Wang, Ying; Xun, Zhili; Liu, Zhixiong; Li, Fenglan; Lu, Hai

    2014-01-01

    Tapetal programmed cell death (PCD) is a prerequisite for pollen grain development in angiosperms, and cysteine proteases are the most ubiquitous hydrolases involved in plant PCD. We identified a papain-like cysteine protease, CEP1, which is involved in tapetal PCD and pollen development in Arabidopsis thaliana. CEP1 is expressed specifically in the tapetum from stages 5 to 11 of anther development. The CEP1 protein first appears as a proenzyme in precursor protease vesicles and is then transported to the vacuole and transformed into the mature enzyme before rupture of the vacuole. cep1 mutants exhibited aborted tapetal PCD and decreased pollen fertility with abnormal pollen exine. A transcriptomic analysis revealed that 872 genes showed significantly altered expression in the cep1 mutants, and most of them are important for tapetal cell wall organization, tapetal secretory structure formation, and pollen development. CEP1 overexpression caused premature tapetal PCD and pollen infertility. ELISA and quantitative RT-PCR analyses confirmed that the CEP1 expression level showed a strong relationship to the degree of tapetal PCD and pollen fertility. Our results reveal that CEP1 is a crucial executor during tapetal PCD and that proper CEP1 expression is necessary for timely degeneration of tapetal cells and functional pollen formation. PMID:25035401

  19. Patterns of ROS accumulation in the stigmas of Angiosperms and visions into their multi-functionality in plant reproduction

    Directory of Open Access Journals (Sweden)

    Adoración Zafra

    2016-08-01

    Full Text Available Accumulation of reactive oxygen species (ROS in the stigma of several plant species has been investigated. Four developmental stages (unopened flower buds, recently opened flowers, dehiscent anthers and flowers after fertilization were analyzed by confocal laser scanning microscopy using the ROS-specific probe DCFH2-DA. In all plants scrutinized, the presence of ROS in the stigmas was detected at higher levels during those developmental phases considered receptive to pollen interaction. In addition, these molecules were also present at early (unopened flower or later (post-fertilization stages, by following differential patterns depending on the different species. The biological significance of the presence ROS may differ between these stages, including defense functions, signaling and senescence. Pollen-stigma signaling is likely involved in the different mechanisms of self-incompatibility in these plants. The study also register a general decrease in the presence of ROS in the stigmas upon pollination, when NO is supposedly produced in an active manner by pollen grains.Finally, the distribution of ROS in primitive Angiosperms of the genus Magnolia was determined. The production of such chemical species in these plants was several orders of magnitude higher than in the remaining species evoking a massive displacement towards the defense function. This might indicate that signaling functions of ROS/NO in the stigma evolved later, as fine tune likely involved in specialized interactions like self-incompatibility.

  20. Ultrastructural aspects of pollen ontogeny in an endangered plant species, Pancratium maritimum L. (Amaryllidaceae).

    Science.gov (United States)

    Tütüncü Konyar, Sevil

    2017-03-01

    Pollen ontogeny in Pancratium maritimum L. was studied from the sporogenous cell to mature pollen grain stages using transmission electron, scanning electron, and light microscopy to determine whether the pollen development in P. maritimum follows the basic scheme in angiosperms or not. In the course of microsporogenesis and microgametogenesis, special attention was given to the considerable ultrastructural changes that are observed in the cytoplasm of microsporocytes, microspores, and mature pollen grains throughout the successive stages of pollen development. Microsporocyte differentiation concerning number and ultrastructure of organelles facilitates the transition of microsporocytes from the sporophytic phase to the gametophytic phase. However, cytoplasmic differentiation of generative and vegetative cells supports their functional distinctness and pollen maturation. Although microsporogenesis and microgametogenesis in P. maritimum generally follow the usual angiosperm pattern, abnormalities such as formation of unreduced gametes were observed. During normal microsporogenesis, meiocytes undergo meiosis and successive cytokinesis, resulting in the formation of isobilateral, decussate, and linear tetrads. Subsequent to the development of free and vacuolated microspores, the first mitotic division occurs and bicellular monosulcate pollen grains are produced. Pollen grains are shed from the anther at binucleate stage. During pollen ontogeny, three periods of vacuolization were observed: in meiocytes, in mononucleate free microspores, and in the generative cell.