Sample records for androgenesis

  1. Albinism in barley androgenesis


    Makowska, Katarzyna; Oleszczuk, Sylwia


    Androgenesis is highly useful for plant breeding, significantly reducing breeding cycle times, as well as in a wide range of biological research. However, for widespread use this process must be efficient. Despite several decades of research on the phenomenon of androgenesis, many processes involved are obscure and there is much to be understood about androgenesis. One of the problems inherent in androgenesis, and reducing its efficiency, is albinism. This article reviews albinism in barley a...

  2. Fine structure of plastids during androgenesis in Hordeum vulgare L.

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    Fortunat Młodzianowski


    Full Text Available The fine structure of plastids was studied in the course of androgenesis in in the pollen of Hordeum vulgare L. It was found that these organelles occur in all stages of androgenesis. Their structure was simple and was frequently manifested on the cross section only by the presence of the envelope and matrix of different degree of density. Single thylakoids, nucleoid-like regions and starch grains were, however, also noted. The structure of plastids in embryoids formed from microspores of barley was compared with embryos developed from fertilized egg cell, and we did not found any fundamental differences between them. However, only plastid ribosomes were difficult to identify on ultrathin sections in embryoids and in the embryos.

  3. Effects of gamma radiation on somatic embryogenesis and androgenesis in various in vitro cultured plant tissues

    International Nuclear Information System (INIS)

    Gamma irradiation with 1000 rad stimulates somatic embryogenesis in carrot plants and androgenesis in tobacco and Datura. The numerous somatic embryos formed are incapable of germination, whereas the androgenetic plantlets develop normally. A cytological study is described. Higher radiation doses of 2,000-10,000 rad have an adverse, or inhibiting, effect on in vitro induced embryogenesis. In the case of tobacco, the formation of albino plantlets is sometimes observed. Genetic changes caused by the action of ionizing radiation should be more distinctly expressed in haploid or diploid individuals and homozygotes formed by androgenesis. (author)


    Czech Academy of Sciences Publication Activity Database

    Dubas, E.; Wedzony, M.; Petrovská, Beáta; Salaj, J.; Zur, I.


    Roč. 52, č. 1 (2010), s. 73-86. ISSN 0001-5296 Institutional research plan: CEZ:AV0Z50380511 Keywords : Androgenesis * microspores * triticale Subject RIV: EF - Botanics Impact factor: 0.586, year: 2010

  5. Effectiveness of androgenesis induced in anther culture of pepper (Capsicum annuum L.)


    Koleva Gudeva, Liljana; Trajkova, Fidanka; Spasenoski, Mirko


    The frequency of obtained androgenic plants de pends highly on the genotype; there fore the low rate of haploid recovery limits the utility of anther culture in pepper breeding. In the present study the effectiveness of induced androgenesis in in vivo anther culture of 19 pep per genotypes was investigated and established. The aim of this study was establishment of effective in vitro technology for study of haploid and diploid plant regenerants; induction of embryogenesis in pepper anth...

  6. Using androgenesis in studies on single cell-derived embryo development

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    Sylwia Oleszczuk


    Full Text Available The method for regeneration of plants from microspores was being developed for the last 50 years. Through the use of this method a tremendous progress in breeding of many important crop plants was achieved. This applies to cereals too. We have developed microspore culture techniques for many cereals and grasses, and here we recommend androgenesis as a tool to study morphological and biochemical changes during the plant embryo development.

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

    DEFF Research Database (Denmark)

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


    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...... consistent with 3-5 nucleate microspores and 2-7 celled structures with no further growth. To gain a further insight into the molecular mechanism underlying the switch from microsporogenesis to androgenesis, bioinformatics tools were employed. The challenges on the roles of such genes were reviewed while an...

  8. Induced artificial androgenesis in common tench, Tinca tinca (L., using common carp and common bream eggs

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    Dariusz Kucharczyk


    Full Text Available This study presents artificial induction using tench eggs, Tinca tinca (L., of androgenetic origin. The oocytes taken from common bream, Abramis brama (L. and common carp, Cyprinus carpio L. were genetically inactivated using UV irradiation and then inseminated using tench spermatozoa. Androgenetic origin (haploid or diploid embryos was checked using a recessive colour (blond and morphological markers. The percentage of hatched embryos in all experimental groups was much lower than in the control groups. All haploid embryos showed morphological abnormalities, which were recorded as haploid syndrome (stunted body, poorly formed retina, etc.. The optimal dose of UV irradiation of common bream and common carp eggs was 3456 J m–2. At this dose, almost 100% of haploid embryos were produced at a hatching rate of over 6%. Lower UV-ray doses affected abnormal embryo development. The highest yield of tench androgenesis (about 2% was noted when eggs were exposed to thermal shock 30 min after egg activation.

  9. Cold-shock eliminates female nucleus in fertilized eggs to induce androgenesis in the loach (Misgurnus anguillicaudatus, a teleost fish

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    Morishima Kagayaki


    Full Text Available Abstract Background Androgenesis (all-male inheritance is generally induced by means of irradiating the eggs to inactivate the maternal genome, followed by fertilization with normal sperm. In fish, the conventional technique for induced androgenesis has been applied for rapid fixation to traits, recovery of cryopreserved genotypes, sex-control, etc. A new method of androgenesis that eliminates the need to irradiate the egg was proposed using the loach, Misgurnus anguillicaudatus (a teleost fish. Results When the eggs of wild-type females were fertilized with sperm of albino or orange phenotype males and cold-shocked at 0 to 3°C for 60 min duration just after fertilization, generally more than 30% (with a peak of 100% of the hatched progeny were androgenotes. While a few of them were the normal diploid, most of them turned out to be abnormal haploid. All-male inheritance was verified by the expression of the recessive color trait (albino or orange and microsatellite genotypes comprising only paternally derived alleles. Nuclear behavior after the cold-shock treatment was traced by microscopic observation of DAPI (4'6-diamidino-2-phenylindole-stained samples and hematoxylin-eosin stained histological sections, and the extrusion of egg (maternal nucleus was observed in eggs treated in the optimum timing. Conclusion In this paper, we demonstrate that cold-shock treatment (at 0 and 3°C of loach eggs for 60 min just after fertilization successfully induces androgenetic haploid development. The most likely mechanism of cold-shock induced androgenesis is an elimination of the egg nucleus together along with the second polar body and subsequent development of a decondensed sperm nucleus or male pronucleus.

  10. A novel nucleo-cytoplasmic hybrid clone formed via androgenesis in polyploid gibel carp

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    Zhou Li


    Full Text Available Abstract Background Unisexual vertebrates have been demonstrated to reproduce by gynogenesis, hybridogenesis, parthenogenesis, or kleptogenesis, however, it is uncertain how the reproduction mode contributes to the clonal diversity. Recently, polyploid gibel carp has been revealed to possess coexisting dual modes of unisexual gynogenesis and sexual reproduction and to have numerous various clones. Using sexual reproduction mating between clone D female and clone A male and subsequent 7 generation multiplying of unisexual gynogenesis, we have created a novel clone strain with more than several hundred millions of individuals. Here, we attempt to identify genetic background of the novel clone and to explore the significant implication for clonal diversity contribution. Methods Several nuclear genome markers and one cytoplasmic marker, the mitochondrial genome sequence, were used to identify the genetic organization of the randomly sampled individuals from different generations of the novel clone. Results Chromosome number, Cot-1 repetitive DNA banded karyotype, microsatellite patterns, AFLP profiles and transferrin alleles uniformly indicated that nuclear genome of the novel clone is identical to that of clone A, and significantly different from that of clone D. However, the cytoplasmic marker, its complete mtDNA genome sequence, is same to that of clone D, and different from that of clone A. Conclusions The present data indicate that the novel clone is a nucleo-cytoplasmic hybrid between the known clones A and D, because it originates from the offspring of gonochoristic sexual reproduction mating between clone D female and clone A male, and contains an entire nuclear genome from the paternal clone A and a mtDNA genome (cytoplasm from the maternal clone D. It is suggested to arise via androgenesis by a mechanism of ploidy doubling of clone A sperm in clone D ooplasm through inhibiting the first mitotic division. Significantly, the selected nucleo

  11. Genetic changes after androgenesis in the millet Pennisetum americanum: Study of descendants from cultures of pollen of an F1 hybrid (Massue X Ligui)

    International Nuclear Information System (INIS)

    Self-fertilizing generations of double haploid plants obtained by androgenesis from an F1 hybrid (Massue X Ligui) of the millet Pennisetum americanum were investigated. Four enzyme systems were studied by electrophoresis (for four loci in particular: Adh1, esterase 1, peroxidase P5, catalase, which are heterozygous in F1), as well as 20 morphological and phenological characteristics (analysed by principal component analysis and by hierarchical variance analysis). The biochemical and biometric studies combined to show considerable distortions in segregation (generally in favour of characteristics of the Massue line) and great variability of genetic origin revealed during successive self-fertilizations of the double haploids. Part of this variability could be explained by partial non-reduction phenomena (never total non-reduction, since no plant produced by androgenesis has all the characteristics of the F1 generation). However, recourse must also be had to other phenomena analogous to genetic instabilities in order to account for the appearance of new functional states (detected by electrophoresis) in the S1 and S2 generations and the fact that some of the intra-family variations do not become weaker as the genealogy progresses. (author)

  12. Optimisation of UV Treatment Duration to Induce Haploid Androgenesis in the Nile tilapia (Oreochromis niloticus L.)


    Karayücel, İsmihan; Karayücel, Sedat


    The optimum UV duration times of eggs were examined in order to develop a simple and safe method for inducing androgenetic development in the Nile tilapia, Oreochromis niloticus. The yield of androgenetic haploid O. niloticus to the pigmentation stage was 18.53 ± 5.3% (relative to controls) with an optimal UV irradiation dose of 540 Jm-2 (at 150 µWcm-2 ) for 6 min. Most embryos developing after fertilisation with normal spermatozoa showed abnormal morphology and a haploid number of chromosome...

  13. Clonal reproduction with androgenesis and somatic recombination: the case of the ant Cardiocondyla kagutsuchi (United States)

    Okita, Ichiro; Tsuchida, Koji


    In haplodiploid insects such as ants, male sexuals develop from unfertilised haploid eggs, while female sexuals and workers develop from fertilized diploid eggs. However, some ant species do not exchange their gene pool between sexes; both male and female sexuals are clonally produced, while workers are sexually produced. To date, three ant species, Wasmannia auropunctata, Vollenhovia emeryi, and Paratrechina longicornis, have been reported to reproduce using such reproductive systems. In this study, we reveal that in one lineage of the ant Cardiocondyla kagutsuchi, male and female sexuals are also clonally produced. In contrast to the abovementioned three species, the workers were not only sexually produced but had recombinant sequences in their nuclear internal transcribed spacer regions, although the recombinant sequences were not detected in male or female sexuals. These results suggest that the lineage likely possesses a mechanism to compensate for the reduction in genetic variation due to clonal reproduction with somatic recombination that occurs within the workers.

  14. Effects of free and chelated iron on in vitro androgenesis in barley and wheat

    Czech Academy of Sciences Publication Activity Database

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


    Roč. 63, - (2000), s. 35-40. ISSN 0167-6857 R&D Projects: GA ČR GV521/96/K117 Institutional research plan: CEZ:AV0Z5038910 Keywords : ferrous ions * Hordeum vulgare * Triticum aestivum Subject RIV: EF - Botanics Impact factor: 0.444, year: 2000

  15. "Obtaining haploids in anther culture of pepper (C. annuum L.) and their inclusion in the breeding process"


    Koleva Gudeva, Liljana


    The aim of research in this project was directed towards examining the regenerative potential of several different genotypes of pepper Capsicum annuum L., especially the ability for androgenesis and creation of haploid and diploid pepper fund. The subject of research was to expand knowledge about androgenesis in pepper and to examine the morphogenesis and the role of plant growth regulators (especially auxins and cytokinins) on the development of regenerants under in vitro conditions.

  16. Callus Production and Plant Regeneration from Anther Culture of Some Turkish Barley Cultivars


    SAVAŞKAN, Çigdem


    Anther culture of four different barley cultivars ( Hordeum vulgareL. cvs. Anadolu, Cumhuriyet-50, Obruk-86 and Tokak-157/37) currently cultivated in Turkey has been investigated. Two different culture media (BAC3 and FHG) were used and the effect of a 21-day cold pretreatment was studied. Androgenesis on BAC3 medium was evaluated statistically in all genotypes and the percentage of anther response and the frequency of calli production were found significantly different (P

  17. Effects of chronic exposure to sodium arsenite on hypothalamo-pituitary-testicular activities in adult rats: possible an estrogenic mode of action


    Jana Subarna; Jana Kuladip; Samanta Prabhat


    Abstract Background Inorganic arsenic is a major water pollutant and a known human carcinogen that has a suppressive influence on spermatogenesis and androgenesis in male reproductive system. However, the actual molecular events resulting in male reproductive dysfunctions from exposure to arsenic remain unclear. In this context, we evaluated the mode of action of chronic oral exposure of sodium arsenite on hypothalamo-pituitary- testicular activities in mature male albino rats. Methods The ef...

  18. Adrenocortical function and reserve in children treated for acute lymphoblastic leukemia; Czynnosc i rezerwa korowo-nadnerczowa u dzieci po leczeniu ostrej bialaczki limfoblastycznej

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    Pawlaczyk, B.; Malecka, E.H.; Krause, W. [Instytut Pediatrii, Akademia Medyczna, Poznan (Poland)


    Serum cortisol and 17 OHS, 17 KS and DHA levels in 24-hour urine were determined in 30 children (22 girls and boys) 0.5 to 4 years after completion of therapy (radio- and chemotherapy) for acute lymphoblastic leukemia (ALL). Serum cortisol after Syncthen (adrenocortical reserve) was determined in 15 girls and 4 boys. The results show that therapy for ALL depresses glucocorticosteroid synthesis; however, it does not disturb the adrenal reserve or androgenesis. (author) 15 refs, 6 tabs

  19. Anther Culture of Pepper: Morphological Characteristics of Fruits of Androgenetic Pepper Lines (Capsicum Annuum L.)


    Koleva Gudeva, Liljana; Trajkova, Fidanka


    The presented study describes the effectiveness of induced androgenesis in in vitro pepper anther culture. The aim of this study was the establishment of effective technology for induction of embryogenesis in pepper anther culture; development of the embryos into plantlets; successful adaptation and acclimatization of plantlets from sterile to greenhouse conditions, and the breeding process of obtained androgenetic pepper lines in the plastic tunnel conditions. From 19 pepper genotypes under ...

  20. Aneuploidy among androgenic progeny of hexaploid triticale (XTriticosecale Wittmack). (United States)

    Oleszczuk, Sylwia; Rabiza-Swider, Julita; Zimny, Janusz; Lukaszewski, Adam J


    Doubled haploids are an established tool in plant breeding and research. Of several methods for their production, androgenesis is technically simple and can efficiently produce substantial numbers of lines. It is well suited to such crops as hexaploid triticale. Owing to meiotic irregularities of triticale hybrids, aneuploidy may affect the efficiency of androgenesis more severely than in meiotically stable crops. This study addresses the issue of aneuploidy among androgenic regenerants of triticale. Plant morphology, seed set and seed quality were better predictors of aneuploidy, as determined cytologically, than flow cytometry. Most aneuploids were hypoploids and these included nullisomics, telosomics, and translocation lines; among 42 chromosome plants were nulli-tetrasomics. Rye chromosomes involved in aneuploidy greatly outnumbered wheat chromosomes; in C(0) rye chromosomes 2R and 5R were most frequently involved. While the frequency of nullisomy 2R was fairly constant in most cross combinations, nullisomy 5R was more frequent in the most recalcitrant combination, and its frequency increased with time spent in culture with up to 70% of green plants recovered late being nullisomic 5R. Given that 5R was not involved in meiotic aberrations with an above-average frequency, it is possible that its absence promotes androgenesis or green plant regeneration. Overall, aneuploidy among tested combinations reduced the average efficiency of double haploid production by 35% and by 69% in one recalcitrant combination, seriously reducing the yield of useful lines. PMID:21170716

  1. Study of in vitro anther culture in selected genotypes of genus Capsicum


    OLSZEWSKA, Dorota; Kisiala, Anna; NIKLAS-NOWAK, Aleksandra; NOWACZYK, Pawel


    The combined effect of anther incubation time on CP induction medium (12, 14, and 16 days) and 2 concentrations of kinetin in R1 regeneration medium (0.1 and 0.3 mg/L) on the effectiveness of androgenesis was investigated in 17 genotypes of Capsicum grown in Poland. Plant material consisted of breeding lines and intraspecific hybrids of C. annuum; the species of C. frutescens, C. chinense, and C. baccatum var. pendulum; interspecific hybrids F1 (C. frutescens × C. chinense) and F1 (C. frutesc...

  2. Specificity of MOAC enrichment applied for mature pollen phosphoproteomics studies

    Czech Academy of Sciences Publication Activity Database

    Fíla, Jan; Matros, A.; Čapková, Věra; Mock, H. P.; Honys, David

    Washington, D.C: IEEE Computer Society, 2012 - (Sloan, K.), s. 523-526 ISBN 978-0-7695-4706-0. [International Conference on Biomedical Engineering and Biotechnology /2012/. Macau (CN), 28.05.2012-30.05.2012] R&D Projects: GA ČR(CZ) GAP501/11/1462; GA MŠk OC08011 Institutional research plan: CEZ:AV0Z50380511 Keywords : androgenesis * male gametophyte * phosphoproteins Subject RIV: ED - Physiology

  3. Haploidization of vegetable plants

    International Nuclear Information System (INIS)

    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)

  4. Reticulate evolution in stick insects: the case of Clonopsis (Insecta Phasmida

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    Milani Liliana


    Full Text Available Abstract Background Phasmids show noteworthy abilities to overcome species-specific reproductive isolation mechanisms, including hybridization, polyploidy, parthenogenesis, hybridogenesis and androgenesis. From an evolutionary standpoint, such tangled reproductive interactions lead to the complex phyletic relationships known as "reticulate evolution". Moroccan stick insects of the genus Clonopsis include one bisexual (C. felicitatis and two closely related parthenogenetic forms (C. gallica, C. soumiae, which represent a polyploid series in chromosome number, but with apparent diploid karyotypes. Moreover, two Clonopsis strains of ameiotic males have been described, C. androgenes-35 and C. androgenes-53. As a consequence, Clonopsis stick insects may have experienced complex micro-evolutionary events, which we try to disentangle in this study. Results Mitochondrial cox2 analysis supports a recent divergence of Clonopsis, while AFLPs evidence genetic differentiation not linked to karyotypes, so that parthenogenetic C. gallica and C. soumiae appear to be a mix of strains of polyphyletic origin rather than single parthenogenetic species. Moreover, an admixed hybrid origin seems to be confirmed for C. androgenes. Conclusion On the whole, Clonopsis is an intriguing case of reticulate evolution. Actually, complex cladogenetic events should be taken into account to explain the observed genetic structure, including diploidization of polyploid karyotypes, possibly coupled with hybridization and androgenesis. We also proposed a "working hypothesis" to account for the observed data, which deserves further studies, but fits the observed data very well.

  5. Distant hybridization leads to different ploidy fishes

    Institute of Scientific and Technical Information of China (English)


    Distant hybridization makes it possible to transfer the genome of one species to another, which results in changes in phenotypes and genotypes of the progenies. This study shows that distant hybridization or the combination of this method with gynogenesis or androgenesis lead to different ploidy fishes with genetic variation, including fertile tetraploid hybrids, sterile triploid hybrids, fertile diploid hybrids, fertile diploid gynogenetic fish, and their derived progenies. The formations of the different ploidy fishes depend on the genetic relationship between the parents. In this study, several types of distant hybridization, including red crucian carp (Carassius auratus red var.) (2n=100, abbreviated as RCC) (♀)×common carp (Cyprinus carpio L.) (2n=100, abbreviated as CC) (♂), and RCC (2n=100) (♀)×blunt snout bream (Megalobrama amblycephala) (2n=48, abbreviated as BSB) (♂) are described. In the distant hybridization of RCC (♀)×CC (♂), bisexual fertile F3–F18 allotetraploid hybrids (4n=200, abbreviated as 4nAT) were formed. The diploid hybrid eggs and diploid sperm generated by the females and males of 4nAT developed into diploid gynogenetic hybrids and diploid androgenetic hybrids, respectively, by gynogenesis and androgenesis, without treatment for doubling the chromosome. Improved tetraploid hybrids and improved diploid fishes with genetic variation were derived from the gynogenetic hybrid line. The improved diploid fishes included the high-body RCC and high-body goldfish. The formation of the tetraploid hybrids was related to the occurrence of unreduced gametes generated from the diploid hybrids, which involved in premeiotic endoreduplication, endomitosis, or fusion of germ cells. The sterile triploid hybrids (3n=150) were produced on a large scale by crossing the males of tetraploid hybrids with females of diploid fish (2n=100). In another distant hybridization of RCC (♀)×BSB (♂), different ploidy fishes were obtained, including

  6. Genetic and epigenetic analysis of recurrent hydatidiform mole. (United States)

    Hayward, Bruce E; De Vos, Michel; Talati, Nargese; Abdollahi, M Reza; Taylor, Graham R; Meyer, Esther; Williams, Denise; Maher, Eamonn R; Setna, Faridon; Nazir, Kausar; Hussaini, Shahnaz; Jafri, Hussain; Rashid, Yasmin; Sheridan, Eamonn; Bonthron, David T


    Familial biparental hydatidiform mole (FBHM) is a maternal-effect autosomal recessive disorder in which recurrent pregnancy failure with molar degeneration occurs. The phenotype mimics molar pregnancy due to androgenesis, despite the normal genetic makeup of the conceptus. FBHM appears to result from a failure to establish correct maternal epigenetic identity at imprinted loci during oogenesis. Several women affected with FBHM have previously been shown to have biallelic mutations in the NLRP7 gene (NALP7). Here, we present the results of epigenetic and mutational analysis on FBHM patients from 11 families, 10 of them novel. We demonstrate a methylation defect at imprinted loci in tissue from four new FBHM cases. Biallelic NLRP7 mutations, including eight previously undescribed mutations, were found in all but one family. These results indicate for the first time that maternal imprints at some loci may be correctly specified in FBHM conceptions, since differential methylation of SGCE/PEG10 was preserved in all four cases. PMID:19309689

  7. Haploidization via Chromosome Elimination: Means and Mechanisms. (United States)

    Ishii, Takayoshi; Karimi-Ashtiyani, Raheleh; Houben, Andreas


    The ability to generate haploids and subsequently induce chromosome doubling significantly accelerates the crop breeding process. Haploids have been induced through the generation of plants from haploid tissues (in situ gynogenesis and androgenesis) and through the selective loss of a parental chromosome set via inter- or intraspecific hybridization. Here, we focus on the mechanisms responsible for this selective chromosome elimination. CENH3, a variant of the centromere-specific histone H3, has been exploited to create an efficient method of haploid induction, and we discuss this approach in some detail. Parallels have been drawn with chromosome-specific elimination, which occurs as a normal part of differentiation and sex determination in many plant and animal systems. PMID:26772657

  8. Production of homozygous transgenic rainbow trout with enhanced disease resistance. (United States)

    Chiou, Pinwen Peter; Chen, Maria J; Lin, Chun-Mean; Khoo, Jenny; Larson, Jon; Holt, Rich; Leong, Jo-Ann; Thorgarrd, Gary; Chen, Thomas T


    Previous studies conducted in our laboratory showed that transgenic medaka expressing cecropin B transgenes exhibited resistant characteristic to fish bacterial pathogens, Pseudomonas fluorescens and Vibrio anguillarum. To confirm whether antimicrobial peptide gene will also exhibit anti-bacterial and anti-viral characteristics in aquaculture important fish species, we produced transgenic rainbow trout expressing cecropin P1 or a synthetic cecropin B analog, CF-17, transgene by sperm-mediated gene transfer method. About 30 % of fish recovered from electroporation were shown to carry the transgene as determined by polymerase chain reaction (PCR) amplification assay. Positive P₁ transgenic fish were crossed to non-transgenic fish to establish F₁ transgenic founder families, and subsequently generating F₂, and F₃ progeny. Expression of cecropin P1 and CF-17 transgenes was detected in transgenic fish by reverse transcription (RT)-PCR analysis. The distribution of body sizes among F₁ transgenic fish were not significantly different from those of non-transgenic fish. Results of challenge studies revealed that many families of F₂ and F₃ transgenic fish exhibited resistance to infection by Aeromonas salmonicida and infectious hematopoietic necrosis virus (IHNV). All-male homozygous cecropin P1 transgenic families were produced by androgenesis from sperm of F₃ heterozygous transgenic fish in one generation. The resistant characteristic to A. salmonicida was confirmed in progeny derived from the outcross of all-male fish to non-transgenic females. Results of our current studies confirmed the possibility of producing disease-resistant homozygous rainbow trout strains by transgenesis of cecropin P1 or CF-17 gene and followed by androgenesis. PMID:24085608

  9. Two point deterministic model for acquisition of in vitro pollen grain androgenetic capacity based on wheat studies

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    Magali Ferrari Grando


    Full Text Available This article discusses, from the standpoint of cellular biology, the deterministic and indeterministic androgenesis theories. The role of the vacuole and of various types of stresses on deviation of the microspore from normal development and the point where androgenetic competence is acquired are examined. Based on extensive literature review and data on wheat studies from our laboratory, a model for androgenetic capacity of pollen grain is proposed. A two point deterministic model for in vitro androgenesis is our proposal for acquisition of androgenetic potential of the pollen grain: the first switch point would be early meiosis and the second switch point the uninucleate pollen stage, because the elimination of cytoplasmatic sporophytic determinants takes place at those two strategic moments. Any abnormality in this process allowing the maintenance of sporophytic informational molecules results in the absence of establishment of a gametophytic program, allowing the reactivation of the embryogenic processEste artigo discute, do ponto de vista da biologia celular, as teorias determinística e indeterminística sobre a androgênese. São examinados o papel do vacúolo e dos diferentes estresses no desvio do grão de pólen de seu desenvolvimento normal e o ponto onde a competência androgenética é adquirida. Baseado numa extensa revisão da literatura e dados de estudos realizados em trigo pelo nosso laboratório, é proposto um modelo para a capacidade androgenética do grão de pólen. O modelo determinístico de dois pontos para androgênese in vitro é nossa proposta para explicar a aquisição da capacidade androgenética do grão de pólen: o primeiro ponto de mudança seria no início da meiose e o segundo ponto de mudança no estádio de pólen uninucleado, porque a eliminação dos determinantes esporofíticos citoplasmáticos ocorre nestes dois pontos estratégicos. Qualquer anormalidade neste processo permite a manutenção das mol

  10. Transmission of the Aegilops ovata chromosomes carrying gametocidal factors in hexaploid triticale (×Triticosecale Wittm.) hybrids. (United States)

    Kwiatek, M; Majka, M; Ślusarkiewicz-Jarzina, A; Ponitka, A; Pudelska, H; Belter, J; Wiśniewska, H


    The main aim of this work was to induce the chromosome rearrangements between Aegilops ovata (UUMM) and hexaploid triticale (AABBRR) by expression of the gametocidal factor located on the chromosome 4M. The Aegilops ovata × Secale cereale (UUMMRR) amphiploids and triticale 'Moreno' were used to produce hybrids by reciprocal crosses. Chromosome dynamics was observed in subsequent generations of hybrids during mitotic metaphase of root meristems and first metaphase of meiosis of pollen mother cells. Chromosomes were identified by genomic in situ hybridisation (GISH) and fluorescence in situ hybridisation (FISH) using pTa71, pTa791, pSc119.2 and pAs1 DNA probes. It has been shown that the origin of the genetic background had an influence on Aegilops chromosome transmission. Moreover, it has been reported that the preferential transmission of chromosome 4M appeared during both androgenesis and gynogenesis. It is also hypothesised that the expression of the triticale Gc gene suppressor had an influence on the semi-fertility of hybrids but did not inhibit the chromosome rearrangements. This paper also describes the double haploid production, which enabled to obtain plants with two identical copies of triticale chromosomes with translocations of Aegilops chromatin segments. PMID:26825077

  11. Improving the efficiency of isolated microspore culture in six-row spring barley: II-exploring novel growth regulators to maximize embryogenesis and reduce albinism. (United States)

    Esteves, Patricio; Clermont, Isabelle; Marchand, Suzanne; Belzile, François


    Two alternative cytokinins, thidiazuron and meta-topoline, were tested in isolated microspore culture on recalcitrant barley genotypes (six-row, spring), and green plant regeneration was improved substantially. Doubled-haploid (DH) plants are coveted in plant breeding and in genetic studies, since they are rapidly obtained and perfectly homozygous. In barley, DHs are produced mainly via androgenesis, and isolated microspore culture (IMC) constitutes the method offering the greatest potential efficiency. However, IMC can often be challenging in some genotypes because of low yield of microspores, low regeneration and high incidence of albinism. Six-row spring-type barleys, the predominant type grown in Eastern Canada, are considered recalcitrant in this regard. Our general objective was to optimize an IMC protocol for DH production in six-row spring barley. In particular, we explored the use of alternative hormones in the induction medium (thidiazuron and dicamba), and in the regeneration medium (meta-topoline). This optimization was performed on two typical six-row spring (ACCA and Léger), a two-row spring (Gobernadora) and a two-row winter (Igri) barley cultivar. When 6-benzyl-aminopurine (BAP) was replaced by a combination of thidiazuron and dicamba in the induction medium, a 5.1-fold increase (P IMC in this recalcitrant type of barley. These results were later successfully validated using sets of F1s from a six-row spring barley breeding program. PMID:24519013

  12. Tissue culture-induced genetic and epigenetic variation in triticale (× Triticosecale spp. Wittmack ex A. Camus 1927) regenerants. (United States)

    Machczyńska, Joanna; Zimny, Janusz; Bednarek, Piotr Tomasz


    Plant regeneration via in vitro culture can induce genetic and epigenetic variation; however, the extent of such changes in triticale is not yet understood. In the present study, metAFLP, a variation of methylation-sensitive amplified fragment length polymorphism analysis, was used to investigate tissue culture-induced variation in triticale regenerants derived from four distinct genotypes using androgenesis and somatic embryogenesis. The metAFLP technique enabled identification of both sequence and DNA methylation pattern changes in a single experiment. Moreover, it was possible to quantify subtle effects such as sequence variation, demethylation, and de novo methylation, which affected 19, 5.5, 4.5% of sites, respectively. Comparison of variation in different genotypes and with different in vitro regeneration approaches demonstrated that both the culture technique and genetic background of donor plants affected tissue culture-induced variation. The results showed that the metAFLP approach could be used for quantification of tissue culture-induced variation and provided direct evidence that in vitro plant regeneration could cause genetic and epigenetic variation. PMID:26337939

  13. Ribulose Bisphosphate Carboxylase Activity in Anther-Derived Plants of Saintpaulia ionantha Wendl. Shag. (United States)

    Bhaskaran, S; Smith, R H; Finer, J J


    Plants obtained from anther culture of the African violet, Saintpaulia ionantha Wendl. ;Shag' and vegetatively cloned copies of the parent anther donor plant were examined for their ploidy and ribulose-1,5-biphosphate carboxylase (RuBPcase) activity. The cloned parent plants were all diploid and did not vary much in their nuclear DNA, chlorophyll, and RuBPcase activity. Some of the anther-derived plants were similar to the parent plants while others were not. Different levels of ploidy were observed among the androgenetic plants. RuBPcase activities higher than that of the parent plants were found in some anther-derived plants. However, there was no direct correlation between ploidy and RuBPcase activity. Expression of nuclear genes from a single parent in the anther-derived plants and it's diploidization or plastid changes during early stages of microsporogenesis or androgenesis are suggested as possible reasons for the variations observed among them. This could be a useful technique to obtain physiological variants which could be agronomically desirable. PMID:16663273

  14. Characterization of health-related compounds in eggplant (Solanum melongena L.) lines derived from introgression of allied species. (United States)

    Mennella, Giuseppe; Rotino, Giuseppe L; Fibiani, Marta; D'Alessandro, Antonietta; Francese, Gianluca; Toppino, Laura; Cavallanti, Federica; Acciarri, Nazzareno; Lo Scalzo, Roberto


    The purpose of the present study was to investigate the levels of either the nutraceutical and health-promoting compounds or the antioxidant properties of innovative eggplant (Solanum melongena L.) genotypes tolerant and/or resistant to fungi, derived from conventional and non-conventional breeding methodologies (i.e., sexual interspecific hybridization, interspecific protoplast electrofusion, androgenesis, and backcross cycles) in comparison with their allied and cultivated parents. Chemical measures of soluble refractometric residue (SRR), glycoalkaloids (solamargine and solasonine), chlorogenic acid (CA), delphinidin 3-rutinoside (D3R), total phenols (TP), polyphenoloxidase (PPO) activity, antiradical activity on superoxide anion and hydroxyl radical were carried out in raw fruit and peel of 57 eggplant advanced introgression lines (ILs), of three eggplant recurrent genotypes and of three allied species during 2005 and 2006. The majority of the ILs, obtained after several backcross cycles, showed positive characteristics with respect to the allied parents such as good levels of SRR, CA, D3R, TP, PPO activity, the scavenging activity against superoxide anion and hydroxyl radical and, in particular, significantly (p

  15. Induction of gynogenetic and androgenetic haploid and doubled haploid development in the brown trout (Salmo trutta Linnaeus 1758). (United States)

    Michalik, O; Dobosz, S; Zalewski, T; Sapota, M; Ocalewicz, K


    Gynogenetic and androgenetic brown trout (Salmo trutta Linnaeus 1758) haploids (Hs) and doubled haploids (DHs) were produced in the present research. Haploid development was induced by radiation-induced genetic inactivation of spermatozoa (gynogenesis) or eggs (androgenesis) before insemination. To provide DHs, gynogenetic and androgenetic haploid zygotes were subjected to the high pressure shock to suppress the first mitotic cleavage. Among haploids, gynogenetic embryos were showing lower mortality when compared to the androgenetic embryos; however, most of them die before the first feeding stage. Gynogenetic doubled haploids provided in the course of the brown trout eggs activation performed by homologous and heterologous sperm (rainbow trout) were developing equally showing hatching rates of 14.76 ± 2.4% and 16.14 ± 2.90% and the survival rates at the first feeding stage of 10.48 ± 3.48% and 12.78 ± 2.18%, respectively. Significantly, lower survival rate was observed among androgenetic progenies from the diploid groups with only few specimens that survived to the first feeding stage. Cytogenetic survey showed that among embryos from the diploid variants of the research, only gynogenetic individuals possessed doubled sets of chromosomes. Thus, it is reasonable to assume that radiation employed for the genetic inactivation of the brown trout eggs misaligned mechanism responsible for the cell divisions and might have delayed or even arrested the first mitotic cleavage in the androgenetic brown trout zygotes. Moreover, protocol for the radiation-induced inactivation of the paternal and maternal genome should be adjusted as some of the cytogenetically surveyed gynogenetic and androgenetic embryos exhibited fragments of the irradiated chromosomes. PMID:25601334

  16. Reprogramming of cassava (Manihot esculenta) microspores towards sporophytic development. (United States)

    Perera, P I P; Ordoñez, C A; Dedicova, B; Ortega, P E M


    Gametes have the unique potential to enter the sporophytic pathway, called androgenesis. The plants produced are usually haploid and recombinant due to the preceding meiosis and they can double their chromosome number to form doubled haploids, which are completely homozygous. Availability of the doubled haploids facilitates mapping the genes of agronomically important traits, shortening the time of the breeding process required to produce new hybrids and homozygous varieties, and saving the time and cost for inbreeding. This study aimed to test the feasibility of using isolated and in vitro cultured immature cassava (Manihot esculenta) microspores to reprogramme and initiate sporophytic development. Different culture media and different concentrations of two ion components (Cu(2+) and Fe(2+)) were tested in two genotypes of cassava. External structural changes, nuclear divisions and cellular changes during reprogramming were analysed by scanning electron microscopy, by staining with 4',6-diamidino-2-phenylindole, and through classical histology and transmission electron microscopy. In two cassava genotypes, different developmental stages of microspores were found to initiate sporophytic cell divisions, that is, with tetrads of TMS 60444 and with mid or late uni-nucleate microspores of SM 1219-9. In the modified NLN medium (NLNS), microspore enlargements were observed. The medium supplemented with either sodium ferrous ethylene-diamine-tetraacetic acid (NaFeEDTA) or CuSO4·5H2O induced sporophytic cell division in both genotypes. A low frequency of the reprogramming and the presence of non-responsive microspores among the responsive ones in tetrads were found to be related to the viability and exine formation of the microspores. The present study clearly demonstrated that reprogramming occurs much faster in isolated microspore culture than in anther culture. This paves the way for the development of an efficient technique for the production of homozygous lines in

  17. Detection of segregation distortion loci in triticale (x Triticosecale Wittmack based on a high-density DArT marker consensus genetic linkage map

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    Weissmann Elmar A


    Full Text Available Abstract Background Triticale is adapted to a wide range of abiotic stress conditions, is an important high-quality feed stock and produces similar grain yield but more biomass compared to other crops. Modern genomic approaches aimed at enhancing breeding progress in cereals require high-quality genetic linkage maps. Consensus maps are genetic maps that are created by a joint analysis of the data from several segregating populations and different approaches are available for their construction. The phenomenon that alleles at a locus deviate from the Mendelian expectation has been defined as segregation distortion. The study of segregation distortion is of particular interest in doubled haploid (DH populations due to the selection pressure exerted on the plants during the process of their establishment. Results The final consensus map, constructed out of six segregating populations derived from nine parental lines, incorporated 2555 DArT markers mapped to 2602 loci (1929 unique. The map spanned 2309.9 cM with an average number of 123.9 loci per chromosome and an average marker density of one unique locus every 1.2 cM. The R genome showed the highest marker coverage followed by the B genome and the A genome. In general, locus order was well maintained between the consensus linkage map and the component maps. However, we observed several groups of loci for which the colinearity was slightly uneven. Among the 2602 loci mapped on the consensus map, 886 showed distorted segregation in at least one of the individual mapping populations. In several DH populations derived by androgenesis, we found chromosomes (2B, 3B, 1R, 2R, 4R and 7R containing regions where markers exhibited a distorted segregation pattern. In addition, we observed evidence for segregation distortion between pairs of loci caused either by a predominance of parental or recombinant genotypes. Conclusions We have constructed a reliable, high-density DArT marker consensus genetic linkage

  18. Morphological markers for microspore developmental stage in maize

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    Ana Paula de Moraes


    Full Text Available The use of maize in anther culture has been limited because only few genotypes presented a high androgenetic potential. Obtaining the proper stage of microspore development at culture initiation is one of the most crucial factors for success in the androgenesis. For Brazilian maize genotypes there are no studies reporting a correlation between cytological features and morphological parameters. In this study, morphological parameters were recorded and associated with cytological specific stages of the the microsporogenesis in two Brazilian maize genotypes that were sowed in different places (field and growing chamber. For both genotypes, the plants of the growing chamber presented a delay in development. Spikelets length and anther length/spikelet length ratio are not good parameters since they can be greatly influenced by the environment. The anther length was the more reliable parameter to correlate with a specific developmental stage. Nevertheless, variations between genotypes and environment were detected.A utilização do milho (Zea mays na cultura de anteras é limitada devido ao baixo número de genótipos com alto potencial androgenético. A obtenção de micrósporos no estádio de desenvolvimento apropriado no início da cultura é um dos fatores cruciais para o sucesso do processo androgenético. Em genótipos brasileiros de milho não existem estudos relatando a correlação entre características citológicas e parâmetros morfológicos. Neste estudo, parâmetros morfológicos foram avaliados e associados com estádios específicos da microsporogênese em dois genótipos brasileiros de milho os quais foram semeados em diferentes locais (campo e câmara de crescimento. Para ambos os genótipos, as plantas crescidas na câmara de crescimento apresentaram atraso no desenvolvimento. O comprimento da espigueta e a razão comprimento da antera/comprimento da espigueta não são bons parâmetros uma vez que podem ser muito influenciados

  19. Quantification of the tissue-culture induced variation in barley (Hordeum vulgare L.

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    Bednarek Piotr T


    Full Text Available Abstract Background When plant tissue is passaged through in vitro culture, many regenerated plants appear to be no longer clonal copies of their donor genotype. Among the factors that affect this so-called tissue culture induced variation are explant genotype, explant tissue origin, medium composition, and the length of time in culture. Variation is understood to be generated via a combination of genetic and/or epigenetic changes. A lack of any phenotypic variation between regenerants does not necessarily imply a concomitant lack of genetic (or epigenetic change, and it is therefore of interest to assay the outcomes of tissue culture at the genotypic level. Results A variant of methylation sensitive AFLP, based on the isoschizomeric combinations Acc65I/MseI and KpnI/MseI was applied to analyze, at both the sequence and methylation levels, the outcomes of regeneration from tissue culture in barley. Both sequence mutation and alteration in methylation pattern were detected. Two sets of regenerants from each of five DH donor lines were compared. One set was derived via androgenesis, and the other via somatic embryogenesis, developed from immature embryos. These comparisons delivered a quantitative assessment of the various types of somaclonal variation induced. The average level of variation was 6%, of which almost 1.7% could be accounted for by nucleotide mutation, and the remainder by changes in methylation state. The nucleotide mutation rates and the rate of epimutations were substantially similar between the andro- and embryo-derived sets of regenerants across all the donors. Conclusion We have developed an AFLP based approach that is capable of describing the qualitative and quantitative characteristics of the tissue culture-induced variation. We believe that this approach will find particular value in the study of patterns of inheritance of somaclonal variation, since non-heritable variation is of little interest for the improvement of plant

  20. 小麦×玉米远缘杂交技术以及在单倍体育种上的应用评价%The Distant Hybridization Technology of Wheat×Maize System and Application Evaluation of Haploid Breeding

    Institute of Scientific and Technical Information of China (English)

    陈淑萍; 王雪征; 唐怀君; 茜晓哲


    为了提高小麦作物育种选择的精确性和效率,应用小麦亲本杂交后代F1(或F2)代与玉米进行远缘杂交,经激素诱导和组织培养形成单倍体胚及植株,加倍单倍体(DH)育种结合分子标记和性状表达,达到了单代纯化培育小麦新品系的生产能力;本文阐述了小麦×玉米远缘杂交发展进程,分析了小麦×玉米远缘杂交较孤雄生殖、球茎大麦技术等具备的优势特点,探讨了提高单倍体胚、单倍体植株产生频率以及染色体加倍效率的途径,展望了小麦×玉米杂交组合对于未来高效改进小麦育种程序具有的巨大潜力和发展前景.%In order to in crease the precision and efficacy of selection process in crop breeding, the distant hybridization between wheat filial generation of F, (or F2) and Maize intergeneric crosses is applied, after auxin 2,4-D induction and tissue culture, polyhaploid embryo and plant have developed, The use of dihaploid (DH) technology combining with molecular marker-assisted selection (MAS) and trait expression greatly enhances the production of complete homozygous wheat lines in a single generation; In this paper, we try to elucidate the methods available for haploid production, reveal the superiority of wheatxmaize system of crosses over Androgenesis and Bulbosum techniques, research the strategic on enhancement of embryo formation, green polyhaploid plant regeneration and doubled haploid, look ahead the potentiality and the prospect of wheatxmaize system of crosses for improving the efficiency of future wheat breeding program.

  1. Genetic studies on sex determination and colouration in Nile tilapia (Oreochromis niloticus L.)

    International Nuclear Information System (INIS)

    The present study was undertaken to investigate colour and sex determination mechanisms through the application of androgenesis, gynogenesis and controlled breeding programme with the objective of producing all red males in O. niloticus. The highest yield of androgenetic haploid to pigmentation stage was 24.6±3.5% (relative to controls) with optimal UV irradiation dose of 450JM-2 for 5 minutes. The highest survival rate of diploid androgens was 0.07±0.07% (relative to controls) to yolk sac stage using a heat shock of 42.5 deg. C for 3 minutes 30 seconds applied at 25 minutes after fertilisation. All paternal inheritance of diploid androgenetic tilapia was verified using DNA fingerprinting. The mean recombination frequency of the red skin colour gene in meiotic gynogens was 0.12±0.04. All maternal inheritance of meiotic gynogens was verified using the isozyme locus ADA*. Analyses of sex ratios of meiotic gynogens suggested that male progenies were produced by an epistatic sex determining locus (SDL-2 with two alleles SR and sr) causing female to male sex reversal in the homozygous phase (srsr) but with limited penetrance. A close linkage was found between a sex determining locus (SDL-2) and the red gene. No significant difference was found between colour genotypes (namely homozygous red, heterozygous red and wild type) in terms of total fecundity, ISI (inter spawning interval), egg size and survival rate. Overall mean ISI was 26.3±1.0 days. Mean total fecundity was 1096 eggs. Fecundity varied over successive spawns but this variation did not appear to be related to spawning periodicity. Hormonal and thermal feminization were compared on all YY male progeny of O. niloticus. While similar female percentages of 32.0±5.2 and 33.8±1.5% were produced, significantly higher intersex percentages of 18.5±2.5 and 1.6±0.8 were observed in heat and DES treated groups, respectively. Heat treatment groups showed the lowest survival rate of 62.6±9.8% compared to the

  2. Genetic studies on sex determination and colouration in Nile tilapia (Oreochromis niloticus L.)

    Energy Technology Data Exchange (ETDEWEB)

    Karayuecel, I


    The present study was undertaken to investigate colour and sex determination mechanisms through the application of androgenesis, gynogenesis and controlled breeding programme with the objective of producing all red males in O. niloticus. The highest yield of androgenetic haploid to pigmentation stage was 24.6{+-}3.5% (relative to controls) with optimal UV irradiation dose of 450JM{sup -2} for 5 minutes. The highest survival rate of diploid androgens was 0.07{+-}0.07% (relative to controls) to yolk sac stage using a heat shock of 42.5 deg. C for 3 minutes 30 seconds applied at 25 minutes after fertilisation. All paternal inheritance of diploid androgenetic tilapia was verified using DNA fingerprinting. The mean recombination frequency of the red skin colour gene in meiotic gynogens was 0.12{+-}0.04. All maternal inheritance of meiotic gynogens was verified using the isozyme locus ADA*. Analyses of sex ratios of meiotic gynogens suggested that male progenies were produced by an epistatic sex determining locus (SDL-2 with two alleles SR and sr) causing female to male sex reversal in the homozygous phase (srsr) but with limited penetrance. A close linkage was found between a sex determining locus (SDL-2) and the red gene. No significant difference was found between colour genotypes (namely homozygous red, heterozygous red and wild type) in terms of total fecundity, ISI (inter spawning interval), egg size and survival rate. Overall mean ISI was 26.3{+-}1.0 days. Mean total fecundity was 1096 eggs. Fecundity varied over successive spawns but this variation did not appear to be related to spawning periodicity. Hormonal and thermal feminization were compared on all YY male progeny of O. niloticus. While similar female percentages of 32.0{+-}5.2 and 33.8{+-}1.5% were produced, significantly higher intersex percentages of 18.5{+-}2.5 and 1.6{+-}0.8 were observed in heat and DES treated groups, respectively. Heat treatment groups showed the lowest survival rate of 62

  3. Effects of chronic exposure to sodium arsenite on hypothalamo-pituitary-testicular activities in adult rats: possible an estrogenic mode of action

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    Jana Subarna


    Full Text Available Abstract Background Inorganic arsenic is a major water pollutant and a known human carcinogen that has a suppressive influence on spermatogenesis and androgenesis in male reproductive system. However, the actual molecular events resulting in male reproductive dysfunctions from exposure to arsenic remain unclear. In this context, we evaluated the mode of action of chronic oral exposure of sodium arsenite on hypothalamo-pituitary- testicular activities in mature male albino rats. Methods The effect of chronic oral exposure to sodium arsenite (5 mg/kg body weight/day via drinking water without or with hCG (5 I.U./kg body weight/day and oestradiol (25 micrograms oestradiol 3-benzoate suspended in 0.25 ml olive oil/rat/day co-treatments for 6 days a week for 4 weeks (about the duration of two spermatogenic cycle was evaluated in adult male rats. Changes in paired testicular weights, quantitative study of different varieties of germ cells at stage VII of spermatogenic cycle, epididymal sperm count, circulatory concentrations of hormones (LH, FSH, testosterone and corticosterone, testicular activities of delta 5, 3beta-hydroxysteroid dehydrogenase (delta 5, 3beta-HSD, 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD, sorbitol dehydrogenase (SDH, acid phosphatase (ACP, alkaline phosphatase (ALP, and lactate dehydrogenase (LDH, as well as the levels of biogenic amines (dopamine, noradrenaline and 5-hydroxytryptamine (5-HT in the hypothalamus and pituitary were monitored in this study. Hormones were assayed by radioimmuno- assay or enzyme- linked immunosorbent assay and the enzymes were estimated after spectrophotometry as well as the biogenic amines by HPLC electrochemistry. Results Sodium arsenite treatment resulted in: decreased paired testicular weights; epididymal sperm count; plasma LH, FSH, testosterone and testicular testosterone concentrations; and increased plasma concentration of corticosterone. Testicular enzymes such as delta 5, 3 beta

  4. 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


    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