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Sample records for hybrid rice seed

  1. Efficacy of Selected Insecticides Applied to Hybrid Rice Seed

    Science.gov (United States)

    Adams, A.; Gore, J.; Musser, F.; Cook, D.; Walker, T.; Dobbins, C.

    2016-01-01

    Hybrid rice and insecticide seed treatments targeting rice water weevil, Lissorhoptrus oryzophilus Kuschel, have altered the landscape of rice production. The effect of reduced seeding rates on seed treatment efficacy in hybrid rice has not been studied. During 2011 and 2012, an experiment was conducted at seven locations to determine the relationship between low seeding rates used in hybrid rice and efficacy of selected insecticidal seed treatments as measured by rice water weevil densities and yield. Labeled rates of thiamethoxam, chlorantraniliprole, and clothianidin were compared with higher rates of these products to determine if labeled rates provide an acceptable level of control of the rice water weevil. Study locations were divided into low, moderate, and high groups based on rice water weevil larval densities. All seed treatments and seed treatment rates reduced rice water weevil densities. However, there was no observed yield or economic benefit from the use of an insecticidal seed treatment in areas of low pressure. Differences in yield were observed among seed treatments and seed treatment rates in moderate and high pressure locations, and all seed treatments yielded better than the untreated plots, but these differences were not always economical. All seed treatments showed an economic advantage in areas of high weevil pressure, and there were no differences among seed treatment products or rates, suggesting that currently labeled seed treatment rates in hybrid rice are effective for rice water weevil management. PMID:26537671

  2. Studies on optimum harvest time for hybrid rice seed.

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    Fu, Hong; Cao, Dong-Dong; Hu, Wei-Min; Guan, Ya-Jing; Fu, Yu-Ying; Fang, Yong-Feng; Hu, Jin

    2017-03-01

    Timely harvest is critical for hybrid rice to achieve maximum seed viability, vigor and yield. However, how to predict the optimum harvest time has been rarely reported so far. The seed vigor of Zhuliangyou 06 (ZLY06) increased and reached the highest level at 20 days after pollination (DAP), when seed moisture content had a lower value, which was maintained until final seed maturation. For Chunyou 84 (CY84), seed vigor, fresh and dry weight had relatively high values at 25 DAP, when seed moisture content reached the lowest value and changed slightly from 25 to 55 DAP. In both hybrid rice varieties, seed glume chlorophyll content declined rapidly from 10 to 30 DAP and remained at a very low level after 35 DAP. Starch content exhibited an increasing trend during seed maturation, while both soluble sugar content and amylase activity decreased significantly at the early stages of seed development. Moreover, correlation analyses showed that seed dry weight, starch content and superoxide dismutase activity were significantly positively correlated with seed vigor. In contrast, chlorophyll content, moisture content, soluble sugar, soluble protein, abscisic acid, gibberellin content, electrical conductivity, catalase and ascorbate peroxidase activities were significantly negatively correlated with seed vigor. Physiological and biochemical parameters were obviously more closely related with seed vigor than with seed germinability during seed development. Seed vigor could be better used as a comprehensive factor to predict the optimum seed harvest time. It is suggested that for ZLY06 seeds could be harvested as early as 20 DAP, whereas for CY84 the earliest optimum harvest time was 25 DAP. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  3. Optimizing hill seeding density for high-yielding hybrid rice in a single rice cropping system in South China.

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    Danying Wang

    Full Text Available Mechanical hill direct seeding of hybrid rice could be the way to solve the problems of high seeding rates and uneven plant establishment now faced in direct seeded rice; however, it is not clear what the optimum hill seeding density should be for high-yielding hybrid rice in the single-season rice production system. Experiments were conducted in 2010 and 2011 to determine the effects of hill seeding density (25 cm×15 cm, 25 cm×17 cm, 25 cm×19 cm, 25 cm×21 cm, and 25 cm×23 cm; three to five seeds per hill on plant growth and grain yield of a hybrid variety, Nei2you6, in two fields with different fertility (soil fertility 1 and 2. In addition, in 2012 and 2013, comparisons among mechanical hill seeding, broadcasting, and transplanting were conducted with three hybrid varieties to evaluate the optimum seeding density. With increases in seeding spacing from 25 cm×15 cm to 25 cm×23 cm, productive tillers per hill increased by 34.2% and 50.0% in soil fertility 1 and 2. Panicles per m2 declined with increases in seeding spacing in soil fertility 1. In soil fertility 2, no difference in panicles per m2 was found at spacing ranging from 25 cm×17 cm to 25 cm×23 cm, while decreases in the area of the top three leaves and aboveground dry weight per shoot at flowering were observed. Grain yield was the maximum at 25 cm×17 cm spacing in both soil fertility fields. Our results suggest that a seeding density of 25 cm×17 cm was suitable for high-yielding hybrid rice. These results were verified through on-farm demonstration experiments, in which mechanical hill-seeded rice at this density had equal or higher grain yield than transplanted rice.

  4. Performance of super hybrid rice cultivars grown under no-tillage and direct seeding

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    Min Huang

    2012-04-01

    Full Text Available Good progress has been made in the super hybrid rice (Oryza sativa L. breeding in China. However, rice yield not only depends on the genetic characteristics but also on the agronomic practices. No-tillage and direct seeding (NTDS is a simplified cultivation technology that greatly simplifies both land preparation and crop establishment. Aiming to determine the grain yield performance of super hybrid rice under NTDS and to identify critical factors that determine grain yield, field experiments were conducted in Nanxian, Hunan Province, China in 2009 and 2010. Two super hybrid cultivars, Liangyoupeijiu and Y-liangyou 1, were grown under conventional tillage and transplanting (CTTP and NTDS. Grain yield, yield components, biomass production, crop growth rate and biomass accumulation during sowing to heading (HD and HD to maturity were measured for each cultivar. There was no difference in grain yield under NTDS and CTTP. However, grain yield differed with cultivar and year. Y-liangyou 1 produced 4 % higher grain yield than Liangyoupeijiu in 2009, whereas in 2010 both cultivars yielded similarly. Grain yields of both cultivars were higher in 2009 than in 2010. Higher grain yield of Y-liangyou 1 in 2009 was associated with higher spikelet filling (spikelet filling percentage and grain weight, which resulted from higher biomass production. Crop growth rate after HD was critical for biomass production by the super hybrid rice. We suggest that increasing the crop growth rate after HD is an effective approach to increase grain yield of super hybrid rice under NTDS.

  5. Construction of a male sterility system for hybrid rice breeding and seed production using a nuclear male sterility gene

    OpenAIRE

    Chang, Zhenyi; Chen, Zhufeng; Wang, Na; Xie, Gang; Lu, Jiawei; Yan, Wei; Zhou, Junli; Tang, Xiaoyan; Deng, Xing Wang

    2016-01-01

    Nuclear male sterility is common in flowering plants, but its application in hybrid breeding and seed production is limited because of the inability to propagate a pure male sterile line for commercial hybrid seed production. Here, we characterized a rice nuclear gene essential for sporophytic male fertility and constructed a male sterility system that can propagate the pure male sterile seeds on a large scale. This system is fundamentally advantageous over the current cytoplasmic male steril...

  6. 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.

  7. Physiological changes and sHSPs genes relative transcription in relation to the acquisition of seed germination during maturation of hybrid rice seed.

    Science.gov (United States)

    Zhu, Li-Wei; Cao, Dong-Dong; Hu, Qi-Juan; Guan, Ya-Jing; Hu, Wei-Min; Nawaz, Aamir; Hu, Jin

    2016-03-30

    During the production of early hybrid rice seed, the seeds dehydrated slowly and retained high moisture levels when rainy weather lasted for a couple of days, and the rice seeds easily occurred pre-harvest sprouting (PHS) along with high temperature. Therefore it is necessary to harvest the seeds before the PHS occurred. The seeds of hybrid rice (Oryza sativa L. subsp. indica) cv. Qianyou No1 that harvests from 19 to 28 days after pollination (DAP) all had high seed vigour. The seed moisture content at 10 DAP was 36.1%, and declined to 28.6% at 19 DAP; the contents of soluble sugar and total starch increased significantly with the development of seeds. The soluble protein content, the level of abscisic acid (ABA) and gibberellin (GA3 ), and ascorbate peroxidase (APX) activity continued to decrease from 10 DAP to 19 DAP. The seeds at 19 DAP had the highest peroxidase (POD) activity and lowest catalase (CAT) activity while the superoxide dismutase (SOD) activity had no significant difference among the different developing periods. The relative expressions of genes 64S Hsp18.0 and Os03g0267200 transcripts increased significantly from 10 to 19 DAP, and then decreased. However, no significant change was recorded in soluble protein, sugar and GA3 after 16 DAP, and they all significantly correlated with seed viability and vigour during the process of seed maturity. The seeds of hybrid rice Qianyou No1 had a higher viability and vigour when harvested from 19 DAP to 28 DAP, the transcription levels of 64S Hsp18.0 and Os03g0267200 increased significantly from 10 DAP to 19 DAP and the highest value was recorded at 19 DAP. The seeds could be harvested as early as 19 DAP without negative influence on seed vigour and viability. © 2015 Society of Chemical Industry.

  8. Construction of a male sterility system for hybrid rice breeding and seed production using a nuclear male sterility gene.

    Science.gov (United States)

    Chang, Zhenyi; Chen, Zhufeng; Wang, Na; Xie, Gang; Lu, Jiawei; Yan, Wei; Zhou, Junli; Tang, Xiaoyan; Deng, Xing Wang

    2016-12-06

    The breeding and large-scale adoption of hybrid seeds is an important achievement in agriculture. Rice hybrid seed production uses cytoplasmic male sterile lines or photoperiod/thermo-sensitive genic male sterile lines (PTGMS) as female parent. Cytoplasmic male sterile lines are propagated via cross-pollination by corresponding maintainer lines, whereas PTGMS lines are propagated via self-pollination under environmental conditions restoring male fertility. Despite huge successes, both systems have their intrinsic drawbacks. Here, we constructed a rice male sterility system using a nuclear gene named Oryza sativa No Pollen 1 (OsNP1). OsNP1 encodes a putative glucose-methanol-choline oxidoreductase regulating tapetum degeneration and pollen exine formation; it is specifically expressed in the tapetum and miscrospores. The osnp1 mutant plant displays normal vegetative growth but complete male sterility insensitive to environmental conditions. OsNP1 was coupled with an α-amylase gene to devitalize transgenic pollen and the red fluorescence protein (DsRed) gene to mark transgenic seed and transformed into the osnp1 mutant. Self-pollination of the transgenic plant carrying a single hemizygous transgene produced nontransgenic male sterile and transgenic fertile seeds in 1:1 ratio that can be sorted out based on the red fluorescence coded by DsRed Cross-pollination of the fertile transgenic plants to the nontransgenic male sterile plants propagated the male sterile seeds of high purity. The male sterile line was crossed with ∼1,200 individual rice germplasms available. Approximately 85% of the F1s outperformed their parents in per plant yield, and 10% out-yielded the best local cultivars, indicating that the technology is promising in hybrid rice breeding and production.

  9. Evaluation of the agronomic performance of atrazine-tolerant transgenic japonica rice parental lines for utilization in hybrid seed production.

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    Luhua Zhang

    Full Text Available Currently, the purity of hybrid seed is a crucial limiting factor when developing hybrid japonica rice (Oryza sativa L.. To chemically control hybrid seed purity, we transferred an improved atrazine chlorohydrolase gene (atzA from Pseudomonas ADP into hybrid japonica parental lines (two maintainers, one restorer, and Nipponbare, by using Agrobacterium-mediated transformation. We subsequently selected several transgenic lines from each genotype by using PCR, RT-PCR, and germination analysis. In the presence of the investigated atrazine concentrations, particularly 150 µM atrazine, almost all of the transgenic lines produced significantly larger seedlings, with similar or higher germination percentages, than did the respective controls. Although the seedlings of transgenic lines were taller and gained more root biomass compared to the respective control plants, their growth was nevertheless inhibited by atrazine treatment compared to that without treatment. When grown in soil containing 2 mg/kg or 5 mg/kg atrazine, the transgenic lines were taller, and had higher total chlorophyll contents than did the respective controls; moreover, three of the strongest transgenic lines completely recovered after 45 days of growth. After treatment with 2 mg/kg or 5 mg/kg of atrazine, the atrazine residue remaining in the soil was 2.9-7.0% or 0.8-8.7% respectively, for transgenic lines, and 44.0-59.2% or 28.1-30.8%, respectively, for control plants. Spraying plants at the vegetative growth stage with 0.15% atrazine effectively killed control plants, but not transgenic lines. Our results indicate that transgenic atzA rice plants show tolerance to atrazine, and may be used as parental lines in future hybrid seed production.

  10. Influence of Genetic Drift of Restoring Gene (Rf on Seed Purity of Yuetai A, a Honglian-Type Cytoplasmic Male Sterile Line in Hybrid Rice

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    Ji-feng Wang

    2008-06-01

    Full Text Available The seed samples of Yuetai A, a Honglian (HL type cytoplasmic male sterile (CMS line in hybrid rice were investigated to assess the seed purity and to analyze the cause of off-type plants by imitating the biological contaminant to Yuetai A in Nanjing, Jiangsu Province and Lingshui, Hainan Province during 2004–2006. The seed impurity of Yuetai A mainly resulted from the genetic drift of restoring fertility gene (Rf after biological contamination but not from its sterility unstability. All of the ten maintainer lines, five restorer lines and three thermo-sensitive genic male sterile lines used in the study could pollinate Yuetai A and Yuetai B to produce F1 plants, directly or indirectly resulting in Rf-gene drifting into Yuetai A and generating ‘iso-cytoplasm restoring-generations’. Furthermore, high outcrossing rate and similar heading date of Yuetai A with many varieties used in rice production might easily result in the biological contamination. After removing all plants with Rf-gene mixed in Yuetai A and preventing Rf-gene drifting into Yuetai A, the seed purity of Yuetai A and Yuetai B had been raised to 100%.

  11. Proteomics of Rice Seed Germination

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    Dongli eHe

    2013-07-01

    Full Text Available Seed is a condensed form of plant. Under suitable environmental conditions, it can resume the metabolic activity from physiological quiescent status, and mobilize the reserves, biosynthesize new proteins, regenerate organelles and cell membrane, eventually protrude the radicle and enter into seedling establishment. So far, how these activities are regulated in a coordinated and sequential manner is largely unknown. With the availability of more and more genome sequence information and the development of mass spectrometry (MS technology, proteomics has been widely applied in analyzing the mechanisms of different biological processes, and proved to be very powerful. Regulation of rice seed germination is critical for rice cultivation. In recent years, a lot of proteomic studies have been conducted in exploring the gene expression regulation, reserves mobilization and metabolisms reactivation, which brings us new insights on the mechanisms of metabolism regulation during this process. Nevertheless, it also invokes a lot of questions. In this mini-review, we summarized the progress in the proteomic studies of rice seed germination. The current challenges and future perspectives were also discussed, which might be helpful for the following studies.

  12. Asian wild rice is a hybrid swarm with extensive gene flow and feralization from domesticated rice.

    Science.gov (United States)

    Wang, Hongru; Vieira, Filipe G; Crawford, Jacob E; Chu, Chengcai; Nielsen, Rasmus

    2017-06-01

    The domestication history of rice remains controversial, with multiple studies reaching different conclusions regarding its origin(s). These studies have generally assumed that populations of living wild rice, O. rufipogon , are descendants of the ancestral population that gave rise to domesticated rice, but relatively little attention has been paid to the origins and history of wild rice itself. Here, we investigate the genetic ancestry of wild rice by analyzing a diverse panel of rice genomes consisting of 203 domesticated and 435 wild rice accessions. We show that most modern wild rice is heavily admixed with domesticated rice through both pollen- and seed-mediated gene flow. In fact, much presumed wild rice may simply represent different stages of feralized domesticated rice. In line with this hypothesis, many presumed wild rice varieties show remnants of the effects of selective sweeps in previously identified domestication genes, as well as evidence of recent selection in flowering genes possibly associated with the feralization process. Furthermore, there is a distinct geographical pattern of gene flow from aus , indica , and japonica varieties into colocated wild rice. We also show that admixture from aus and indica is more recent than gene flow from japonica , possibly consistent with an earlier spread of japonica varieties. We argue that wild rice populations should be considered a hybrid swarm, connected to domesticated rice by continuous and extensive gene flow. © 2017 Wang et al.; Published by Cold Spring Harbor Laboratory Press.

  13. Mutant-inducing effect of γ-ray irradiation for hybrid rice F1 derived from cross of black glutinous rice x wild rice

    International Nuclear Information System (INIS)

    Mao Dezhi; Tang Yilan

    1998-01-01

    The hybrid rice F 1 plant derived from the back crossing of glutinous rice x wild rice was irradiated with γ-ray. The result of investigation to the induced mutant showed that through the selection and backcross, a black glutinous rice strain with the short stem, cold tolerance and high yield was developed. The analysis of the ability of heredity variance showed that the selection was effective for the husk colour, black glutinous and black Indica rice, but ineffective for the white Indica rice and seed setting

  14. Evidence for Non-Transmission of Rice Yellow Mottle Virus (RYMV through Rice Seed

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    Sy, AA.

    2004-01-01

    Full Text Available An indexing of the organs (radicle and plumule and components (husk, endosperm and embryo of rice seeds using Enzyme Linked Immunosorbent Assay (ELISA was carried out to detect Rice yellow mottle virus (RYMV and establish the exact location of the virus in the rice seed. RYMV was detected only in the husk (seed coat but not in the endosperm, plumule, radicle, nor embryo. None of the seedlings raised from the seeds expressed RYMV symptoms. No virus particle was detected by the ELISA test in the leaves of the screenhouse-reared plants obtained from seeds of infected plants. The results indicate that RYMV is apparently not transmitted through rice seed probably because the virus is seed-borne in the husk (seed coat of mature rice seeds.

  15. Response of rice genotypes to weed competition in dry direct-seeded rice in India.

    Science.gov (United States)

    Mahajan, Gulshan; Ramesha, Mugalodi S; Chauhan, Bhagirath S

    2014-01-01

    The differential weed-competitive abilities of eight rice genotypes and the traits that may confer such attributes were investigated under partial weedy and weed-free conditions in naturally occurring weed flora in dry direct-seeded rice during the rainy seasons of 2011 and 2012 at Ludhiana, Punjab, India. The results showed genotypic differences in competitiveness against weeds. In weed-free plots, grain yield varied from 6.6 to 8.9 t ha(-1) across different genotypes; it was lowest for PR-115 and highest for the hybrid H-97158. In partial weedy plots, grain yield and weed biomass at flowering varied from 3.6 to 6.7 t ha(-1) and from 174 to 419 g m(-2), respectively. In partial weedy plots, grain yield was lowest for PR-115 and highest for PR-120. Average yield loss due to weed competition ranged from 21 to 46% in different rice genotypes. The study showed that early canopy closure, high leaf area index at early stage, and high root biomass and volume correlated positively with competitiveness. This study suggests that some traits (root biomass, leaf area index, and shoot biomass at the early stage) could play an important role in conferring weed competitiveness and these traits can be explored for dry-seeded rice.

  16. Influence of Rice Seeding Rate on Efficacies of Neonicotinoid and Anthranilic Diamide Seed Treatments against Rice Water Weevil

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    Jason Hamm

    2014-12-01

    Full Text Available Rice in the U.S. is frequently seeded at low rates and treated before sowing with neonicotinoid or anthranilic diamide insecticides to target the rice water weevil. A previous study of the influence of seeding rate on rice water weevil densities showed an inverse relationship between seeding rates and immature weevil densities. This study investigated interactive effects of seeding rate and seed treatment on weevil densities and rice yields; in particular, experiments were designed to determine whether seed treatments were less effective at low seeding rates. Four experiments were conducted over three years by varying seeding rates of rice treated at constant per seed rates of insecticide. Larval suppression by chlorantraniliprole was superior to thiamethoxam or clothianidin, and infestations at low seeding rates were up to 47% higher than at high seeding rates. Little evidence was found for the hypothesis that seed treatments are less effective at low seeding rates; in only one of four experiments was the reduction in weevil densities by thiamethoxam greater at high than at low seeding rates. However, suppression of larvae by neonicotinoid seed treatments in plots seeded at low rates was generally poor, and caution must be exercised when using the neonicotioids at low seeding rates.

  17. The absorption ability for carbohydrate between vigorous and weak spikelets in hybrid rice and its restorers

    International Nuclear Information System (INIS)

    Wang Xi; Tao Longxing; Tian Shulan; Huang Xiaolin; Yu Meiyu

    2000-01-01

    Some hybrid rice combinations and their restorers, II you2070 (indica/Indica) and its restorer2070, Shuangyou23 (Japonica/Japonica) with its restorer 91-23, sub-species hybrid rice Xieyou 413 (Indica/Japonica) with its restorer Zhong 413, were selected as rice material and planted in pot and field to study the differences of absorption ability for labelled carbohydrate between vigorous and weak spikelets, and to demonstrate the phenomenon of 'inter-grain apical dominance' in rice. It was shown that the absorbing rate of hybrid rice and it restorer for store material and for photo-material was 50% and 80% respectively, and the absorbing rate of hybrid rice was a litter higher than that of its restorer. However, there was a big difference between vigorous spikelets and weak spikelets in the absorbing ability for carbohydrate. The absorbing amount of vigorous spikelets was 10 times higher than that of the weak spikelets, especially in hybrid rice combinations. It was also observed that the 'inter-grain apical dominance' in hybrid rice was stronger than its restorer, which might be one of the main reasons for low seed setting in hybrid rice combination

  18. Integrating Soil Silicon Amendment into Management Programs for Insect Pests of Drill-Seeded Rice.

    Science.gov (United States)

    Villegas, James M; Way, Michael O; Pearson, Rebecca A; Stout, Michael J

    2017-08-13

    Silicon soil amendment has been shown to enhance plant defenses against insect pests. Rice is a silicon-accumulating graminaceous plant. In the southern United States, the rice water weevil and stem borers are important pests of rice. Current management tactics for these pests rely heavily on the use of insecticides. This study evaluated the effects of silicon amendment when combined with current management tactics for these rice insect pests in the field. Field experiments were conducted from 2013 to 2015. Rice was drill-planted in plots subjected to factorial combinations of variety (conventional and hybrid), chlorantraniliprole seed treatment (treated and untreated), and silicon amendment (treated and untreated). Silicon amendment reduced densities of weevil larvae on a single sampling date in 2014, but did not affect densities of whiteheads caused by stem borers. In contrast, insecticidal seed treatment strongly reduced densities of both weevil larvae and whiteheads. Higher densities of weevil larvae were also observed in the hybrid variety in 2014, while higher incidences of whiteheads were observed in the conventional variety in 2014 and 2015. Silicon amendment improved rice yields, as did chlorantraniliprole seed treatment and use of the hybrid variety.

  19. Adoption Study Of Seed Priming Technology In Upland Rice ...

    African Journals Online (AJOL)

    Adoption study was carried out during 2003 cropping season on randomly selected 83 farmers out of the 300 that participated in the upland rice seed priming technology transfer between year 2000 – 2002 to determine the impact of the technology on upland rice production in five States of Nigeria, through the use of ...

  20. Effect of acetic acid on rice seeds coated with rice husk ash

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    Lizandro Ciciliano Tavares

    2013-06-01

    Full Text Available Flooded rice cultivation promotes anaerobic conditions, favoring the formation of short chain organic acids such as acetic acid, which may be toxic to the crop. The objective of this study was to evaluate the effect of acetic acid on rice seeds coated with rice husk ash. The experiment was arranged in a 2 x 5 x 5 factorial randomized design, with two cultivars (IRGA 424 and BRS Querência, five doses of coating material (0, 2, 3,4 e 5 g kg-1 seed and five concentrations of acetic acid (0, 3, 6, 9 and 12 mM, with 4 replications, totaling 50 treatments. The variables first count of germination, germination, shoot and root length, dry weight of shoots and roots were recorded. The results showed that coating rice seeds with rice husk ash up to 5 g kg-1 seed does not influence the performance of rice seeds of cultivars IRGA 424 and BRS Querência when exposed to concentrations of 12 mM acetic acid. The presence of acetic acid in the substrates used for seed germination reduced the vigor and viability of seeds of cultivars IRGA 424 and BRS Querência, as well as seedling development, affecting mainly the roots of BRS Querência.

  1. Assessment of Rice Associated Bacterial Ability to Enhance Rice Seed Germination and Rice Growth Promotion

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    R. Gholamalizadeh

    2017-08-01

    Full Text Available ABSTRACT The application of beneficial bacteria has recently been used for sustainable agriculture. In current research, 71 bacterial isolates were obtained from rice plant and the rhizosphere soil of different paddy fields in Guilan province, Iran. After primitive investigation, 40 bacteria with typical predominant characteristics were selected. By PCR-RFLP of their 16S r-DNA gene, 8 Operational Taxonomic Units (OTUs totally consisted of 33 isolates were obtained. From all of them, 8 isolates were selected for rice seed germination experiment, then, effective isolates were used for pot experiment to evaluate their ability for promoting rice growth. All of them were able to increase rice growth and yield, but in different potential. These tested isolates were identified as Alcaligenes faecalis (DEp8, O1R4, Pantoea ananatis (AEn1, Bacillus vietnamensis (MR5, Bacillus idriensis (MR2 and Stenotrophomonas maltophilia by partial sequencing of their 16S r-DNA gene. Among them, AEn1 and MR5 produced indole-3- acetic acid (IAA in larger amounts than the other isolates and the isolates AEn1 and O1R4 were able to solubilize phosphate in higher amounts. According to the results obtained, it can be concluded that AEn1, O1R4 and MR5 can be considered as bacterial inoculants to use as alternatives for chemical fertilizers.

  2. Physiological quality of rice seed submitted to gamma radiation

    International Nuclear Information System (INIS)

    Miranda, Helen Lucia da Cruz; Tillmann, Maria Angela Andre; Meneghello, Geri Eduardo

    2009-01-01

    The objective of this research was to evaluate the effects of the gamma radiation ( 60 Co) on the physiological quality of rice seeds. The research was carried out through three tests; in the first test rice seeds were irradiated at dosages of 0; 1; 2.5 and 5Gy, while for the second and third tests the seeds were subjected to accelerated aging before being irradiated. For the second test the seeds were divided into wet and dry and both groups subjected to accelerated aging previous to irradiation at dosages of 0; 1; 2.5 and 5Gy. For the third test the seeds were dried after being subjected to accelerated aging, and then irradiated at dosages of 0, 10, 25 and 50Gy. To assess the physiological effects of the gamma radiation, all seeds were tested for germination and their germination speed index recorded. Seedling growth was graded through the measurement of the lengths of the first leaf and seminal root system and total seedling dry weight, across all tests. The enzymatic activity of acid phosphatase and alpha-amylase was measured on dry seeds from the second test. The results from all tests indicate that the applied gamma radiation dosages did not cause any changes to the physiological quality of rice seeds. (author)

  3. Thoughts and Practice on Some Problems about Research and Application of Two-Line Hybrid Rice

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    Li-yun CHEN

    2011-06-01

    Full Text Available The main problems about research and application of two-line hybrid rice were reviewed, including the confusing nomenclature and male sterile lines classification, the unclear characteristics of photoperiod and temperature responses and the unsuitable site selection for male sterile line and hybrid rice seed production. In order to efficiently and accurately use dual-purpose genic male sterile lines, four types, including PTGMS (photo-thermo-sensitive genic male sterile rice, TGMS (thermo-sensitive genic male sterile rice, reverse PTGMS and reverse TGMS, were proposed. A new idea for explaining the mechanism of sterility in dual-purpose hybrid rice was proposed. The transition from sterile to fertile was involved in the cooperative regulation of major-effect sterile genes and photoperiod and/or temperature sensitive ones. The minor-effect genes with accumulative effect on sterility were important factors that affected the critical temperature of sterility transfer. In order to make better use of dual-purpose lines, the characterization of responses to photoperiod and temperature of PTGMS should be made and the identification method for the characterization of photoperiod and temperature responses of PTGMS should also be put forward. The optimal ecological site for seed production could be determined according to the historical climate data and the requirements for the meteorological conditions during the different periods of seed production.

  4. Seed-vectored endophytic bacteria modulate development of rice seedlings.

    Science.gov (United States)

    Verma, S K; Kingsley, K; Irizarry, I; Bergen, M; Kharwar, R N; White, J F

    2017-06-01

    The aim of the present study was to evaluate the effects of the removal of indigenous bacteria from rice seeds on seedling growth and development. Here we report the presence of three indigenous endophytic bacteria in rice seeds that play important roles in modulating seedling development (shoot and root lengths, and formation of root hairs and secondary roots) and defence against pathogens. Seed-associated bacteria were removed using surface sterilization with NaOCl (bleach) followed by antibiotic treatment. When bacteria were absent, growth of seedlings in terms of root hair development and overall seedling size was less than that of seedlings that contained bacteria. Reactive oxygen staining of seedlings showed that endophytic bacteria became intracellular in root parenchyma cells and root hairs. Roots containing endophytic bacteria were seen to stain densely for reactive oxygen, while roots free of bacteria stained lightly for reactive oxygen. Bacteria were isolated and identified as Enterobacter asburiae (VWB1), Pantoea dispersa (VWB2) and Pseudomonas putida (VWB3) by 16S rDNA sequencing. Bacteria were found to produce indole acetic acid (auxins), inhibited the pathogen Fusarium oxysporum and solubilized phosphate. Reinoculation of bacteria onto seedlings derived from surface-disinfected rice and Bermuda grass seeds significantly restored seedling growth and development. Rice seeds harbour indigenous bacterial endophytes that greatly influence seedling growth and development, including root and shoot lengths, root hair formation and disease susceptibility of rice seedlings. This study shows that seeds of rice naturally harbour bacterial endophytes that play key roles in modulation of seedling development. © 2017 The Society for Applied Microbiology.

  5. Farmers' perception of risk in cultivating hybrid rice in Bangladesh ...

    African Journals Online (AJOL)

    Although there is an enormous potential for improving adoption of hybrid rice in Bangladesh, it is going through some difficulties in practice. Understanding farmers' perception about difficulties is critical to successful promotion. The present study was conducted to analyze farmers' perception of risk in cultivating hybrid rice ...

  6. Lack of Globulin Synthesis during Seed Development Alters Accumulation of Seed Storage Proteins in Rice

    Directory of Open Access Journals (Sweden)

    Hye-Jung Lee

    2015-06-01

    Full Text Available The major seed storage proteins (SSPs in rice seeds have been classified into three types, glutelins, prolamins, and globulin, and the proportion of each SSP varies. It has been shown in rice mutants that when either glutelins or prolamins are defective, the expression of another type of SSP is promoted to counterbalance the deficit. However, we observed reduced abundances of glutelins and prolamins in dry seeds of a globulin-deficient rice mutant (Glb-RNAi, which was generated with RNA interference (RNAi-induced suppression of globulin expression. The expression of the prolamin and glutelin subfamily genes was reduced in the immature seeds of Glb-RNAi lines compared with those in wild type. A proteomic analysis of Glb-RNAi seeds showed that the reductions in glutelin and prolamin were conserved at the protein level. The decreased pattern in glutelin was also significant in the presence of a reductant, suggesting that the polymerization of the glutelin proteins via intramolecular disulfide bonds could be interrupted in Glb-RNAi seeds. We also observed aberrant and loosely packed structures in the storage organelles of Glb-RNAi seeds, which may be attributable to the reductions in SSPs. In this study, we evaluated the role of rice globulin in seed development, showing that a deficiency in globulin could comprehensively reduce the expression of other SSPs.

  7. Water Productivity of Irrigated Rice under Transplanting, Wet Seeding and Dry Seeding Methods of Cultivation

    Directory of Open Access Journals (Sweden)

    Murali, NS.

    1997-01-01

    Full Text Available Water productivity (WP of irrigated lowland rice was determined during the 1994 dry (January to May and wet (August to December seasons on a heavy clay acid sulphate soil. Treatments consisted of three cultivation methods : transplanted rice, pregerminated seeds broadcasted on puddled soil (wet seeding and dry seeds broadcasted on unpuddled soil (dry seeding. In wet and dry seeded plots, continuous standing water condition was initiated 17 days after sowing. Total water requirement for rice production was highest in transplanted plots (755 mm in wet season and 1154 mm in dry season and was lowest in dry seeded plots (505 mm in wet season and 1040 mm in dry season. Dry seeding required no water for land preparation but transplanting and wet seeding methods required 18 - 20 % of total water requirement in dry season and 27 - 29 % in wet season. Total percolation was maximum (99 mm in wet season and 215 mm in dry season in dry seeding method and was minimum (62 mm in wet season and 94 mm in dry season in transplanting method. In dry and wet seeding methods, daily percolation gradually decreased with the age of the crop. Total seepage loss did not show any significant difference between the cultivation methods in the two seasons. Grain yield was not affected by the three cultivation methods in both seasons. Water productivity (the ratio between grain yield and total amount of water used in production was 3.5 - 4.1 kg ha-1 mm-1, 3.8 - 4.4 kg ha-1 mm-1 and 4.1 - 5.5 kg ha-1 mm-1 in transplanted, wet seeded and dry seeded rice, respectively. Labour requirement for land preparation and sowing was maximum in transplanted (219 - 226 man-hours ha-1 followed by wet (104 -112 man-hours ha-1 and dry seeded (94 - 99 man-hours ha-1 methods. However, in wet season extra labour (77 man-hours ha-1 was required for weeding after crop establishment in dry and wet seeding methods. Crop maturity was 20 days earlier in wet and dry seeding methods compared to

  8. Allelic interaction of F1 pollen sterility loci and abnormal chromosome behaviour caused pollen sterility in intersubspecific autotetraploid rice hybrids.

    Science.gov (United States)

    He, J H; Shahid, M Q; Li, Y J; Guo, H B; Cheng, X A; Liu, X D; Lu, Y G

    2011-08-01

    The intersubspecific hybrids of autotetraploid rice has many features that increase rice yield, but lower seed set is a major hindrance in its utilization. Pollen sterility is one of the most important factors which cause intersubspecific hybrid sterility. The hybrids with greater variation in seed set were used to study how the F(1) pollen sterile loci (S-a, S-b, and S-c) interact with each other and how abnormal chromosome behaviour and allelic interaction of F(1) sterility loci affect pollen fertility and seed set of intersubspecific autotetraploid rice hybrids. The results showed that interaction between pollen sterility loci have significant effects on the pollen fertility of autotetraploid hybrids, and pollen fertility further decreased with an increase in the allelic interaction of F(1) pollen sterility loci. Abnormal ultra-structure and microtubule distribution patterns during pollen mother cell (PMC) meiosis were found in the hybrids with low pollen fertility in interphase and leptotene, suggesting that the effect-time of pollen sterility loci interaction was very early. There were highly significant differences in the number of quadrivalents and bivalents, and in chromosome configuration among all the hybrids, and quadrivalents decreased with an increase in the seed set of autotetraploid hybrids. Many different kinds of chromosomal abnormalities, such as chromosome straggling, chromosome lagging, asynchrony of chromosome disjunction, and tri-fission were found during the various developmental stages of PMC meiosis. All these abnormalities were significantly higher in sterile hybrids than in fertile hybrids, suggesting that pollen sterility gene interactions tend to increase the chromosomal abnormalities which cause the partial abortion of male gametes and leads to the decline in the seed set of the autotetraploid rice hybrids. © 2011 The Author(s).

  9. Identification of rice hybrids using microsatellite and RAPD markers

    African Journals Online (AJOL)

    STORAGESEVER

    2009-05-18

    May 18, 2009 ... presence of slower migrating heteroduplex DNA is, there- fore, useful for detection of heterozygous individuals. Maintenance of hybrid seeds conformity in high level is essential for exploitation of hybrid vigor. Therefore, test- ing the hybrid seed purity is necessarily required before its release into the market.

  10. 7 CFR 1400.212 - Growers of hybrid seed.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Growers of hybrid seed. 1400.212 Section 1400.212... AND SUBSEQUENT CROP, PROGRAM, OR FISCAL YEARS Payment Eligibility § 1400.212 Growers of hybrid seed. The existence of a hybrid seed contract for a person or legal entity will not be taken into account...

  11. Characterization and evaluation of rice blast resistance of Chinese indica hybrid rice parental lines

    Directory of Open Access Journals (Sweden)

    Yunyu Wu

    2017-12-01

    Full Text Available The development of resistant varieties and hybrid combinations has been the most effective and economical strategy to control blast disease caused by Magnaporthe oryzae. However, the distribution of major R genes and blast resistance characterization in hybrid rice parents has not been well investigated, resulting in their limited use in hybrid rice blast-resistance breeding. In the present study, 88 elite indica hybrid rice parental lines were evaluated with 30 isolates of M. oryzae collected from the main planting area of indica hybrid rice in China and were characterized for the presence of 11 major resistance genes using molecular markers. The pathogenicity assays showed that four types of hybrid rice parent line showed some resistance to M. oryzae. However, the proportions of highly resistant lines and the mean resistance frequency (RF varied among the four types, with resistance in decreasing order shown by three-line restorer lines, three-line maintainer lines, two-line sterile lines, and two-line restorer lines. All 88 hybrid rice parental lines carried more than one R gene, but none carried the R genes Pi1 and Pi2. Although Pid3 and Pi9 were present only in three-line restorer lines and Pigm only in three-line maintainer lines, the remaining six R genes (Pib, Pid2, Pi5, Pia, Pi54, and Pita were present in the four types of hybrid rice parent with significantly different distribution frequencies. The correlation between R genes and resistance reactions was investigated. The results are expected to provide useful information for rational utilization of major R genes in hybrid rice breeding programs. Keywords: Hybrid rice parental lines, Magnaporthe oryzae, Pi genes, Resistance evaluation, Molecular markers

  12. Responses of Yield Characteristics to High Temperature During Flowering Stage in Hybrid Rice Guodao 6

    Directory of Open Access Journals (Sweden)

    Guan-fu FU

    2008-09-01

    Full Text Available By sowing at different dates during 2005 and 2006 both in paddy fields and greenhouse, a super hybrid rice combination Guodao 6 and a conventional hybrid rice combination Xieyou 46 (as control were used to analyze the differences in heat injury index, seed setting rate, grain yield and its components. Guodao 6 showed more stable yield and spikelet fertility, and lower heat injury index than Xieyou 46. Further studies indicated that the spikelet sterility is positively correlated with the average daily temperature and the maximum daily temperature, with the coefficients of 0.8604 and 0.9850 (P<0.05 respectively in Guodao 6. The effect of high temperature injury on seed setting caused by maximum daily temperature was lower than that by average daily temperature during the grain filling stage.

  13. Isolation and Identification of Burkholderia glumae from Symptomless Rice Seeds

    Directory of Open Access Journals (Sweden)

    Bo Zhu

    2008-06-01

    Full Text Available A survey on isolation and detection of the casual organism of bacterial grain rot of rice was conducted during 1997–2006. In 2006, six pathogenic bacterial strains were isolated from two symptomless seed samples of rice (Oryza sativa L. originally produced in Hainan Province and then planted in Zhejiang Province, China. They were identified as Burkholderia glumae which is the causal organism of bacterial grain rot of rice by physiological characteristics, colony morphology, pathogenicity test, Biolog, fatty acid methyl ester (FAME analysis and RAPD-PCR compared with the four standard reference strains. It is confirmed that there is the infection of B. glumae in so-called ‘health looking seeds’.

  14. Glucose metabolism in gamma-irradiated rice seeds

    International Nuclear Information System (INIS)

    Inoue, M.; Hasegawa, H.; Hori, S.

    1980-01-01

    Gamma-irradiation of 30 kR in rice seeds caused marked inhibition in seedling growth, and prevented the release of reduced sugar during the period of 25 to 76hr after soaking. The C 6 /C 1 ratio following irradiation continued to decrease up to the 76th hour of soaking; the control's ratio tended to increase with comparable soaking time. The percentage recovery of 14 C in carbon dioxide from glucose -1- 14 C was lower in irradiated than in control seeds. These results indicate that gamma-irradiation reduces the participation of the pentose phosphate pathway in glucose catabolism during an early period of germination. (author)

  15. Distribution of assimilates derived from canopy leaves at different milky stage of intergeneric high-yielding hybrid rice

    International Nuclear Information System (INIS)

    Tang Jianjun

    1997-01-01

    Distribution characteristics of assimilates derived from 14 C-glucose fed on different canopy leaves of the high-yielding intergeneric hybrid rice Yuanyou 1 and GER-1, intra-varietal 3-line hybrid rice Shanyou 63, maternal and paternal parents of intergeneric hybrid rice at various ripening stage from flowering stage to late milky stage were studied with pot experiments under greenhouse in 1993 and 1994 in Guangzhou. The results indicates that there exists a significant difference in exportation of radioactivity from the leaf fed, partitioning of radioactivity exported into different organs and importation accumulation percent of total radioactivity in the rice panicle Yuanyou 1 has a high average exportation percent, importation accumulation percent and a stable and sustainable grain-filling process, which results in a high seed-setting rate with large spikelet population

  16. Application of gamma-ray irradiation technique to select, create and develop super rice with high quality to substitute the imported hybrid rice

    International Nuclear Information System (INIS)

    Tran Duy Quy; Tran Duy Vuong; Tran Duy Duong; Bui Huy Thuc

    2015-01-01

    Three varieties NPT3, BQ and TQ14 were selected by irradiation ray source Gamma Co-60 with dry seed, 13% grain moisture and created at 25-30 krad. NPT3 is super rice varieties with characteristics such as: extremely short growing period (105-110 day crop; 130- 135 days in the spring, the average yield of 9-10 tones/ha), quality, stem, leaf stand, suitable for intensive capability, able to resist pests and unfavorable conditions especially the elements of productivity (amylase from 15-16%) and mass produced including hybrid rice as Nhi Uu 868, Thien Nguyen Uu 9, HYT100, etc. BQ rice varieties were high quality, average productivity gain of 7.5- 8.0 ton/ha, equivalent to hybrid rice, short growth period (105-110 days in summer season; 120- 130 days in spring season), and quality rice: content 18-20% amylose, rice delicious, supple as BC15. TQ14 varieties was planted in 2 seasons/ year, with agricultural and biological characteristics as Khang-Dan18 mutant with wide adaptation, high yield potential, the average gain from 5.9 to 6.2 tones/ha, short growth period (105-110 days in summer season, 130-135 days in spring season), insect resistance, quality of rice suitable for manufacturing technology like noodles, instant noodles, rice noodles, Ethanol. (author)

  17. Comparative Transcriptional Profiling of Three Super-Hybrid Rice Combinations

    Directory of Open Access Journals (Sweden)

    Yonggang Peng

    2014-03-01

    Full Text Available Utilization of heterosis has significantly increased rice yields. However, its mechanism remains unclear. In this study, comparative transcriptional profiles of three super-hybrid rice combinations, LY2163, LY2186 and LYP9, at the flowering and filling stages, were created using rice whole-genome oligonucleotide microarray. The LY2163, LY2186 and LYP9 hybrids yielded 1193, 1630 and 1046 differentially expressed genes (DGs, accounting for 3.2%, 4.4% and 2.8% of the total number of genes (36,926, respectively, after using the z-test (p < 0.01. Functional category analysis showed that the DGs in each hybrid combination were mainly classified into the carbohydrate metabolism and energy metabolism categories. Further analysis of the metabolic pathways showed that DGs were significantly enriched in the carbon fixation pathway (p < 0.01 for all three combinations. Over 80% of the DGs were located in rice quantitative trait loci (QTLs of the Gramene database, of which more than 90% were located in the yield related QTLs in all three combinations, which suggested that there was a correlation between DGs and rice heterosis. Pathway Studio analysis showed the presence of DGs in the circadian regulatory network of all three hybrid combinations, which suggested that the circadian clock had a role in rice heterosis. Our results provide information that can help to elucidate the molecular mechanism underlying rice heterosis.

  18. Weed populations and their buried seeds in rice fields of the MUDA area

    International Nuclear Information System (INIS)

    Ismail Sahid; Noor Faezah Zainuddin; Ho Nai Kin

    2002-01-01

    A total of 25 weed species belonging to 15 families were found in rice fields near Kampung Tandop, in the Muda Irrigation Scheme, Kedah, Malaysia. The dominant weeds in dry-seeded rice were Utricularia aurea Lour., Fimbristylis miliacea (L.) vahl., Echinochloa crusgalli (L.) Beauv., Monochoria vaginalis (Burm. Q Presl. and Najas graminea (Del.) Redl. In wet-seeded rice, the dominant species were N. graminea, Lemna minor L., Sphenoclea zeylanica Gaertn., U. aured, and Sagittaria guayanensis H. B. K., while in volunteer seedling rice fields, the dominant species were Echinochloa colonum (L.) Link., Fimbristylis alboviridis C. B. Clarke, E miliacea, Cyperus babakan Steud. and Fuirena umbellata Rottb. Dry-seeded rice fields contained the highest number of weed seeds (930 910/m 2 in the top 15 cm of soil); volunteer seedling rice fields contained 793.162/m 2 and wet-seeded rice fields 712 228/m 2 . In general, the seed numbers declined with increasing soil depth. At 1015 cm depth, seeds of U aurea and S. zeylanica were the most abundant in dry and wet-seeded rice fields, whilst seeds of Scirpusjuncoides Roxb. and E miliacea were most abundant in volunteer seedling fields. (Author)

  19. Impact Of Different Time Planting In Soybeans And Neem Seed Extract Application To Insect Population On Rice Field

    OpenAIRE

    Tamrin Abdullah; Ahdin Gassa; Sri Nur Aminah Ngatimin; Nurariaty Agus And Abdul Fattah

    2015-01-01

    Abstract The purpose of research is to study impact of different time planting of soybean and neem seed extract application to pest insect population on rice field. The research was used Random Block Design in three treatment of insecticides application i.e neem seed extract together with rice planting neem seed extract on soybean 17 days after rice planting synthetic insecticides on 17 days after rice planting Delthametrin on soybean and Chlorpirifos on rice respectively. Research was conduc...

  20. Impact Of Different Time Planting In Soybeans And Neem Seed Extract Application To Insect Population On Rice Field

    OpenAIRE

    Abdullah, Tamrin; Gassa, Ahdin; Ngatimin, Sri Nur Aminah; Agus, Nurariaty; Fattah, Abdul

    2015-01-01

    The purpose of research is to study impact of different time planting of soybean and neem seed extract application to pest insect population on rice field. The research was used Random Block Design in three treatment of insecticides application i.e: neem seed extract together with rice planting, neem seed extract on soybean 17 days after rice planting, synthetic insecticides on 17 days after rice planting (Delthametrin on soybean and Chlorpirifos on rice), respectively. Research was conducted...

  1. Quantitative phosphoproteomic analysis of early seed development in rice (Oryza sativa L.).

    Science.gov (United States)

    Qiu, Jiehua; Hou, Yuxuan; Tong, Xiaohong; Wang, Yifeng; Lin, Haiyan; Liu, Qing; Zhang, Wen; Li, Zhiyong; Nallamilli, Babi R; Zhang, Jian

    2016-02-01

    Rice (Oryza sativa L.) seed serves as a major food source for over half of the global population. Though it has been long recognized that phosphorylation plays an essential role in rice seed development, the phosphorylation events and dynamics in this process remain largely unknown so far. Here, we report the first large scale identification of rice seed phosphoproteins and phosphosites by using a quantitative phosphoproteomic approach. Thorough proteomic studies in pistils and seeds at 3, 7 days after pollination resulted in the successful identification of 3885, 4313 and 4135 phosphopeptides respectively. A total of 2487 proteins were differentially phosphorylated among the three stages, including Kip related protein 1, Rice basic leucine zipper factor 1, Rice prolamin box binding factor and numerous other master regulators of rice seed development. Moreover, differentially phosphorylated proteins may be extensively involved in the biosynthesis and signaling pathways of phytohormones such as auxin, gibberellin, abscisic acid and brassinosteroid. Our results strongly indicated that protein phosphorylation is a key mechanism regulating cell proliferation and enlargement, phytohormone biosynthesis and signaling, grain filling and grain quality during rice seed development. Overall, the current study enhanced our understanding of the rice phosphoproteome and shed novel insight into the regulatory mechanism of rice seed development.

  2. Analysis of seed quality in NS sunflower hybrid seed processed between 2010 and 2014

    Directory of Open Access Journals (Sweden)

    Jokić Goran

    2015-01-01

    Full Text Available This paper analyzed the processed seed of five sunflower hybrid seed developed at the Institute of Field and Vegetable Crops in Novi Sad. The cultivars were Rimi PR, Duško, NS Dukat, Sumo 1 PR and Sremac. The analysis was conducted on seed lots processed between 2010 and 2014 and involved the following parameters: seed purity percentage, 1000-seed weight, germination energy, germination, seed moisture, number of weed seeds per 1000 grams of seed. The results of the study produced the following average values: seed purity - 99.72%, 1000-seed weight - 67.59g, germination energy - 88.2%, germination - 91.8%, seed moisture - 8.3%. There were not found weeds seeds as well as pathogens on the seed samples, these values are all within the legally prescribed limits.

  3. Cytoplasmic-genetic male sterility gene provides direct evidence for some hybrid rice recently evolving into weedy rice

    Science.gov (United States)

    Zhang, Jingxu; Lu, Zuomei; Dai, Weimin; Song, Xiaoling; Peng, Yufa; Valverde, Bernal E.; Qiang, Sheng

    2015-01-01

    Weedy rice infests paddy fields worldwide at an alarmingly increasing rate. There is substantial evidence indicating that many weedy rice forms originated from or are closely related to cultivated rice. There is suspicion that the outbreak of weedy rice in China may be related to widely grown hybrid rice due to its heterosis and the diversity of its progeny, but this notion remains unsupported by direct evidence. We screened weedy rice accessions by both genetic and molecular marker tests for the cytoplasmic male sterility (CMS) genes (Wild abortive, WA, and Boro type, BT) most widely used in the production of indica and japonica three-line hybrid rice as a diagnostic trait of direct parenthood. Sixteen weedy rice accessions of the 358 tested (4.5%) contained the CMS-WA gene; none contained the CMS-BT gene. These 16 accessions represent weedy rices recently evolved from maternal hybrid rice derivatives, given the primarily maternal inheritance of this trait. Our results provide key direct evidence that hybrid rice can be involved in the evolution of some weedy rice accessions, but is not a primary factor in the recent outbreak of weedy rice in China. PMID:26012494

  4. Cytoplasmic-genetic male sterility gene provides direct evidence for some hybrid rice recently evolving into weedy rice.

    Science.gov (United States)

    Zhang, Jingxu; Lu, Zuomei; Dai, Weimin; Song, Xiaoling; Peng, Yufa; Valverde, Bernal E; Qiang, Sheng

    2015-05-27

    Weedy rice infests paddy fields worldwide at an alarmingly increasing rate. There is substantial evidence indicating that many weedy rice forms originated from or are closely related to cultivated rice. There is suspicion that the outbreak of weedy rice in China may be related to widely grown hybrid rice due to its heterosis and the diversity of its progeny, but this notion remains unsupported by direct evidence. We screened weedy rice accessions by both genetic and molecular marker tests for the cytoplasmic male sterility (CMS) genes (Wild abortive, WA, and Boro type, BT) most widely used in the production of indica and japonica three-line hybrid rice as a diagnostic trait of direct parenthood. Sixteen weedy rice accessions of the 358 tested (4.5%) contained the CMS-WA gene; none contained the CMS-BT gene. These 16 accessions represent weedy rices recently evolved from maternal hybrid rice derivatives, given the primarily maternal inheritance of this trait. Our results provide key direct evidence that hybrid rice can be involved in the evolution of some weedy rice accessions, but is not a primary factor in the recent outbreak of weedy rice in China.

  5. Application Of Induced Mutation Combined With Hybridization Method In Rice Improvement In Southern Vietnam

    International Nuclear Information System (INIS)

    Do Khac Thinh; Dao Minh So; Nguyen Thi Cuc; Hung Phi Oanh; Hoang Duc Dung

    2008-01-01

    Rice plays an important role of social-economic issues in Vietnam, especially in Mekong River Delta (MRD). Rice mutation breeding was not initiated until 1992 in Southern Vietnam. Therefore, no mutant rice varieties were cultivated in MRD before 1995. Dry and germinated seeds of varieties as IR64, Tam Xoan, Nang Huong were exposed to 60 Co gamma rays at doses of 200-300 Gy. Population of 10,000-15,000 M1 plants were established by direct seeded practice. Mutant elite lines were used in hybridization program, assessed according to the standard system for rice (IRRI 1996) from M2 - M7 generations. The promising selected lines were tested in multi-location trials. The mutated characters developed so far consist of better resistance to lodging, disease and insect damages, higher tolerance to soil stresses such as acid sulphate, drought etc, and also earliness and higher yield potential. Mutation techniques have shown very useful in rice improvement, especially for characters controlled by close linked genes that are difficult to break by recombination. Some best mutant varieties: VND95-19, VND95-20, VND99-3, TNDB-100 have been released for large-scale production in MRD. Among them, VND95-20 has become one of the top 5 varieties for export and grown annually about 300,000 ha in Southern Vietnam. In combination with hybridization method, some mutants gave promising recombinants in aroma, tolerance to BPH, Grassy Stunt Virus and Ragged Stunt Virus diseases. Selected varieties as VN121, VN24-4 are largely released into production in recent time. (author)

  6. Effect of gamma-irradiation on rice seed DNA. Pt. 1. Yield and molecular size of DNA extracted from irradiated rice seeds

    International Nuclear Information System (INIS)

    Kawamura, Yoko; Konishi, Akihiro; Yamada, Takashi; Saito, Yukio

    1995-01-01

    The effect of gamma-irradiation on the DNA of hulled rice seeds was investigated. The cetyltrimethylammonium bromide (CTAB) method was preferred for the extraction of DNA from rice seeds because of its high quality and good yield. The yield of DNA that was determined by gel electrophoresis, decreased as the irradiation dose increased from 1 kGy. DNA extracted from rice seeds irradiated with a 30 kGy dose showed a molecular size of less than 20 kb, while that from unirradiated rice showed more than 100 kb in electrophoretic profiles. It can be assumed that the decrease in yield was mainly induced by the crosslinking between protein and DNA, and the reduction in molecular size was induced by double-strand breaks. (J.P.N.)

  7. Genetic analysis and hybrid vigor study of grain yield and other quantitative traits in auto tetraploid rice

    International Nuclear Information System (INIS)

    Shahid, M.Q.; Xiong, C.Z.; Juan, L.Y.; Ming, X.H.

    2011-01-01

    Genetic analysis and genotype-by-environment interaction for important traits of auto tetraploid rice were evaluated by additive, dominance and additive X additive model. It was show n that genetic effects had more influence on grain yield and other quantitative traits of auto tetraploid rice than genotypic environment interaction. Plant height, panicle length, seed set , grain yield, dry matter production and 1000-grain weight we re mainly regulated by dominance variance. Additive and additive X additive gene action constructed the main proportion of genetic variance for heading date (flowering), number of panicles, grains per panicle, grain length, however grain width was supposed to be affected by additive X additive and dominance variance. Flag leaf length and width, fresh weight, peduncle length, unfilled grains and awn length were greatly influenced by genotypic environment interaction. Heading date produced highly negative heterosis over mid parent (H pm) and better parent ( H pb), whereas H pm and H pb were detected to be highly positive and significant for grain yield, seed set, peduncle length, filled grains and 1000-grain weight in F/sub 1/ and F/sub 2/ generations. The results indicated that auto tetraploid hybrids 96025 X Jackson (indica/japonica), 96025 X Linglun (indica/indica) and Linglun X Jackson (indica/japonica) showed highly significant hybrid vigor with improved seed set percentage and grain yield. These results suggest that intra-specific auto tetraploid rice hybrids have more hybrid vigor as compared to intra-sub specific auto tetraploid rice hybrids and auto tetraploid rice has the potential to be used for further studies and commercial application. (author)

  8. Association mapping of stigma and spikelet characteristics in rice (Oryza sativa L.)

    Science.gov (United States)

    Hybrid rice exhibits a yield advantage of 15 to 20 percent (or more than one ton of paddy rice per hectare) over the best traditional varieties. Because rice plants are self-pollinating, commercial production of hybrid seed plays a key role in successful implementation of hybrid rice. Stigma exserti...

  9. Organizational analysis of the seed sector of rice in Guinea: stakeholders, perception and institutional linkages

    NARCIS (Netherlands)

    Okry, F.; Mele, van P.; Nuijten, H.A.C.P.; Struik, P.C.; Mongbo, R.L.

    2011-01-01

    This paper analyses the organization of the rice seed sector in Guinea with the overall objectives to assess how organizational settings affect seed supply to small-scale farmers and to suggest institutional changes that would favour seed service and uptake of varieties. Data were collected in

  10. YIELD STABILITY OF NEW HYBRID RICE ACROSS LOCATIONS

    Directory of Open Access Journals (Sweden)

    Satoto

    2016-02-01

    Full Text Available The adaptation of hybrid rice varieties mostly are in specific location and season, but there are some of the varieties have a wide adaptation then adopted by the farmer in the large area. Replicated yield trials were conducted to study the stability of hybrid rice yield and identify the best location to optimize their yield per ha. The trials were conducted in three location such as Sukamandi, Salatiga and Malang during two seasons in 2011. Data across location and season were analazed by using AMMI and Eberhart Russel methods. The AMMI analysis showed that the IR79156A/PK88 was adaptable to favorable environments but unstable. This hybrid is always performing well and produce the higher yield compare to check variety. Some of other hybrids were good only in specific location, i.e. IR62829A/BP2280-1E-12-22 and IR58029A/BP2280-1E-12-22. Those hybrids produced higher yield in Salatiga and Malang, respectively. Seem to AMMI analysis, the result of Eberhart and Russell method also showed that IR79156A/PK81 was the best hybrid with regression slope (b around 1 with the yield average higher than average of all hybrids. It indicated that this hybrid has a wide adaptation and probably can be cultivated in the wider ecosystem.

  11. Gene interaction at seed-awning loci in the genetic background of wild rice.

    Science.gov (United States)

    Ikemoto, Mai; Otsuka, Mitsuharu; Thanh, Pham Thien; Phan, Phuong Dang Thai; Ishikawa, Ryo; Ishii, Takashige

    2017-09-12

    Seed awning is one of the important traits for successful propagation in wild rice. During the domestication of rice by ancient humans, plants with awnless seeds may have been selected because long awns hindered collection and handling activities. To investigate domestication of awnless rice, QTL analysis for seed awning was first carried out using backcross recombinant inbred lines between Oryza sativa Nipponbare (recurrent parent) and O. rufipogon W630 (donor parent). Two strong QTLs were detected in the same regions as known major seed-awning loci, An-1 and RAE2. Subsequent causal mutation surveying and fine mapping confirmed that O. rufipogon W630 has functional alleles at both loci. The gene effects and interactions at these loci were examined using two backcross populations with reciprocal genetic backgrounds of O. sativa Nipponbare and O. rufipogon W630. As awn length in wild rice varied among seeds even in the same plant, awn length was measured based on spikelet position. In the genetic background of cultivated rice, the wild alleles at An-1 and RAE2 had awning effects, and plants having both wild homozygous alleles produced awns whose length was about 70% of those of the wild parent. On the other hand, in the genetic background of wild rice, the substitution of cultivated alleles at An-1 and RAE2 contributed little to awn length reduction. These results indicate that the domestication process of awnless seeds was complicated because many genes are involved in awn formation in wild rice.

  12. Influence of Seed Priming on Performance and Water Productivity of Direct Seeded Rice in Alternating Wetting and Drying

    Directory of Open Access Journals (Sweden)

    Hafeez Ur Rehman

    2015-07-01

    Full Text Available Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated the effect of seed priming and irrigation on crop establishment, tillering, agronomic traits, paddy yield, grain quality and water productivity of direct seeded rice in alternate wetting and drying (DSR-AWD in comparison with direct seeded rice at field capacity (DSR-FC. Seed priming treatments were osmo-priming with KCl (2.2%, CaCl2 (2.2% and moringa leaf extracts (MLE, 3.3% including hydro-priming as control. Among the treatments, seed osmo-primed with MLE emerged earlier and had higher final emergence, followed by osmo-priming with CaCl2. Tillering emergence rate and number of tillers per plant were the highest for seed priming with CaCl2 in DSR-AWD. Total productive and non-productive tillers, panicle length, biological and grain yields, harvest index were highest for seed priming with MLE or CaCl2 in DSR-AWD. Similarly, grain quality, estimated in terms of normal grains, abortive and chalky grains, was also the highest in DSR-AWD with MLE osmo-priming. Benefit cost ratio and water productivity was also the highest in DSR-AWD for seed priming with MLE. In conclusion, seed priming with MLE or CaCl2 can be successfully employed to improve the direct seeded rice performance when practiced with alternate wetting and drying irrigation.

  13. Molecular Mechanisms Underlying γ-Aminobutyric Acid (GABA) Accumulation in Giant Embryo Rice Seeds.

    Science.gov (United States)

    Zhao, Guo-Chao; Xie, Mi-Xue; Wang, Ying-Cun; Li, Jian-Yue

    2017-06-21

    To uncover the molecular mechanisms underlying GABA accumulation in giant embryo rice seeds, we analyzed the expression levels of GABA metabolism genes and contents of GABA and GABA metabolic intermediates in developing grains and germinated brown rice of giant embryo rice 'Shangshida No. 5' and normal embryo rice 'Chao2-10' respectively. In developing grains, the higher GABA contents in 'Shangshida No. 5' were accompanied with upregulation of gene transcripts and intermediate contents in the polyamine pathway and downregulation of GABA catabolic gene transcripts, as compared with those in 'Chao2-10'. In germinated brown rice, the higher GABA contents in 'Shangshida No. 5' were parallel with upregulation of OsGAD and polyamine pathway gene transcripts and Glu and polyamine pathway intermediate contents and downregulation of GABA catabolic gene transcripts. These results are the first to indicate that polyamine pathway and GABA catabolic genes play a crucial role in GABA accumulation in giant embryo rice seeds.

  14. Effect of Neem Seed Kernel Extracts in the Management of Rice ...

    African Journals Online (AJOL)

    user

    conducted to determine the comparative efficacy of neem seed kernel ... sustainable production of rice and are generally not affordable to African peasant farmers. ... system where the use of natural enemies are being emphasized as a major ...

  15. Rapid assessment of rice seed availability for wildlife in harvested fields

    Science.gov (United States)

    Halstead, B.J.; Miller, M.R.; Casazza, Michael L.; Coates, P.S.; Farinha, M.A.; Benjamin, Gustafson K.; Yee, J.L.; Fleskes, J.P.

    2011-01-01

    Rice seed remaining in commercial fields after harvest (waste rice) is a critical food resource for wintering waterfowl in rice-growing regions of North America. Accurate and precise estimates of the seed mass density of waste rice are essential for planning waterfowl wintering habitat extents and management. In the Sacramento Valley of California, USA, the existing method for obtaining estimates of availability of waste rice in harvested fields produces relatively precise estimates, but the labor-, time-, and machineryintensive process is not practical for routine assessments needed to examine long-term trends in waste rice availability. We tested several experimental methods designed to rapidly derive estimates that would not be burdened with disadvantages of the existing method. We first conducted a simulation study of the efficiency of each method and then conducted field tests. For each approach, methods did not vary in root mean squared error, although some methods did exhibit bias for both simulations and field tests. Methods also varied substantially in the time to conduct each sample and in the number of samples required to detect a standard trend. Overall, modified line-intercept methods performed well for estimating the density of rice seeds. Waste rice in the straw, although not measured directly, can be accounted for by a positive relationship with density of rice on the ground. Rapid assessment of food availability is a useful tool to help waterfowl managers establish and implement wetland restoration and agricultural habitat-enhancement goals for wintering waterfowl. ?? 2011 The Wildlife Society.

  16. Seedling vigor and genetic variability for rice seed, seedling emergence and seedling traits

    International Nuclear Information System (INIS)

    Ali, S.S.; Jafri, S.J.H.; Jamil, M.; Ijaz, M.

    1994-01-01

    Eleven local rice cultivars including Basmati 370 were evaluated for seedling vigor. Three groups of traits were evaluated viz; seed traits (Seed density, seed volume see weight, paddy length and grain length), seed emergence traits (emergence %, emergence index and emergence rate index), and seedling traits (fresh root length, dry root weight, emergence percentage, root length, dry root weight, seed weight and relative root weight were observed significant, respectively. Seed density, relative root weight, emergence rate index and root to shoot ratio were relatively more amenable to improvement. Relative expected genetic advance was the function of heritability and coefficient of phenotypic variability, latter being more important. (author)

  17. 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.

  18. Analysis of Recombinant Proteins in Transgenic Rice Seeds: Identity, Localization, Tolerance to Digestion, and Plant Stress Response.

    Science.gov (United States)

    Wakasa, Yuhya; Takaiwa, Fumio

    2016-01-01

    Rice seeds are an ideal production platform for high-value recombinant proteins in terms of economy, scalability, safety, and stability. Strategies for the expression of large amounts of recombinant proteins in rice seeds have been established in the past decade and transgenic rice seeds that accumulate recombinant products such as bioactive peptides and proteins, which promote the health and quality of life of humans, have been generated in many laboratories worldwide. One of the most important advantages is the potential for direct oral delivery of transgenic rice seeds without the need for recombinant protein purification (downstream processing), which has been attributed to the high expression levels of recombinant products. Transgenic rice will be beneficial as a delivery system for pharmaceuticals and nutraceuticals in the future. This chapter introduces the strategy for producing recombinant protein in the edible part (endosperm) of the rice grain and describes methods for the analysis of transgenic rice seeds in detail.

  19. A Quantitative Acetylomic Analysis of Early Seed Development in Rice (Oryza sativa L.).

    Science.gov (United States)

    Wang, Yifeng; Hou, Yuxuan; Qiu, Jiehua; Li, Zhiyong; Zhao, Juan; Tong, Xiaohong; Zhang, Jian

    2017-06-27

    PKA (protein lysine acetylation) is a critical post-translational modification that regulates various developmental processes, including seed development. However, the acetylation events and dynamics on a proteomic scale in this process remain largely unknown, especially in rice early seed development. We report the first quantitative acetylproteomic study focused on rice early seed development by employing a mass spectral-based (MS-based), label-free approach. A total of 1817 acetylsites on 1688 acetylpeptides from 972 acetylproteins were identified in pistils and seeds at three and seven days after pollination, including 268 acetyproteins differentially acetylated among the three stages. Motif-X analysis revealed that six significantly enriched motifs, such as (DxkK), (kH) and (kY) around the acetylsites of the identified rice seed acetylproteins. Differentially acetylated proteins among the three stages, including adenosine diphosphate (ADP) -glucose pyrophosphorylases (AGPs), PDIL1-1 (protein disulfide isomerase like 1-1), hexokinases, pyruvate dehydrogenase complex (PDC) and numerous other regulators that are extensively involved in the starch and sucrose metabolism, glycolysis/gluconeogenesis, tricarboxylic acid (TCA) cycle and photosynthesis pathways during early seed development. This study greatly expanded the rice acetylome dataset, and shed novel insight into the regulatory roles of PKA in rice early seed development.

  20. Proteomic analysis of seed storage proteins in wild rice species of the Oryza genus.

    Science.gov (United States)

    Jiang, Chunmiao; Cheng, Zaiquan; Zhang, Cheng; Yu, Tengqiong; Zhong, Qiaofang; Shen, J Qingxi; Huang, Xingqi

    2014-01-01

    The total protein contents of rice seeds are significantly higher in the three wild rice species (Oryza rufipogon Grill., Oryza officinalis Wall. and Oryza meyeriana Baill.) than in the cultivated rice (Oryza sativa L.). However, there is still no report regarding a systematic proteomic analysis of seed proteins in the wild rice species. Also, the relationship between the contents of seed total proteins and rice nutritional quality has not been thoroughly investigated. The total seed protein contents, especially the glutelin contents, of the three wild rice species were higher than those of the two cultivated rice materials. Based on the protein banding patterns of SDS-PAGE, O. rufipogon was similar to the two cultivated rice materials, followed by O. officinalis, while O. meyeriana exhibited notable differences. Interestingly, O. meyeriana had high contents of glutelin and low contents of prolamine, and lacked 26 kDa globulin band and appeared a new 28 kDa protein band. However, for O. officinali a 16 kDa protein band was absent and a row of unique 32 kDa proteins appeared. In addition, we found that 13 kDa prolamine band disappeared while special 14 kDa and 12 kDa protein bands were present in O. officinalis. Two-dimensional gel electrophoresis (2-DE) analysis revealed remarkable differences in protein profiles of the wild rice species and the two cultivated rice materials. Also, the numbers of detected protein spots of the three wild rice species were significantly higher than those of two cultivated rice. A total of 35 differential protein spots were found for glutelin acidic subunits, glutelin precursors and glutelin basic subunits in wild rice species. Among those, 18 protein spots were specific and 17 major spots were elevated. Six differential protein spots for glutelin acidic subunits were identified, including a glutelin type-A 2 precursor and five hypothetical proteins. This was the first report on proteomic analysis of the three wild rice species

  1. IMPORTANCE OF STORAGE CONDITIONS AND SEED TREATMENT FOR SUNFLOWER HYBRIDS SEEDS GERMINATION

    Directory of Open Access Journals (Sweden)

    Goran Krizmanić

    2014-12-01

    Full Text Available In this research we have determined germination energy and germination of seeds of sunflower hybrids ‘Luka’ and ‘Apolon’, at the beginning of storage and 6, 12 and 18 months after of storage period (2011-2012 in the floor concrete storage at two different air temperatures and humidity (S-1: air temperature 15-18°C and relative air humidity 65-70% as well as in climate chamber (S-2: air temperature 10-12°C and relative air humidity 60-65%, stored in four treatments (Control: processed-untreated seed; T-1: treated with A.I. metalaxyl-M; T-2: treated with A.I. metalaxyl-M + A.I. imidacloprid and T-3: treated with A.I. metalaxyl-M + A.I. clothianidin. Based on the obtained results we have determined that sunflower hybrid ‘Luka’, compared to hybrid ‘Apolon’, in the given storage conditions and with the same seed treatment has 5-8% higher germination energy and seed germination and that in climate chamber both hybrids have 5-7% higher germination energy. Seed treatment of both sunflower hybrids with A.I. imidacloprid maximally reduced initial germination energy and seed germination in all tested periods and conditions of storage. On the average, natural seed, after 18 months of storage did not have better seed quality compared to seed treated with A.I. metalaxyl-M while other treatments had more significant influence on reduction of germination energy and seed germination, 6-15%. On the average, compared to other variants, seeds treated with A.I. metalaxyl-M after 18 months of storage in both storage conditions had higher germination energy by 4-15%, and seed germination by 2-12%.

  2. Investigation of Hg uptake and transport between paddy soil and rice seeds combining Hg isotopic composition and speciation

    OpenAIRE

    C. Feng; Z. Pedrero; P. Li; B. Du; X. Feng; M. Monperrus; E. Tessier; S. Berail; D. Amouroux

    2016-01-01

    Abstract Human consumption of rice constitutes a potential toxicological risk in mercury (Hg) polluted areas such as Hg mining regions in China. It is recognized to be an important source of Hg for the local human diet considering the efficient bioaccumulation of methylmercury (MeHg) in rice seed. To assess Hg sources and uptake pathways to the rice plants, Hg speciation and isotopic composition were investigated in rice seeds and their corresponding paddy soils from different locations withi...

  3. Interspecific variation of total seed protein in wild rice germplasm using SDS-Page

    International Nuclear Information System (INIS)

    Shah, S.M.A.; Hidayat-ur-Rahman; Abbasi, F.M.; Ashiq, M.; Rabbani, A.M.; Khan, I.A.; Shinwari, Z.K.; Shah, Z.

    2011-01-01

    Variation in seed protein of 14 wild rice species (Oryza spp.) along with cultivated rice species (O. sativa) was studied using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) to assess genetic diversity in the rice germplasm. SDS bands were scored as present (1) or absent (0) for protein sample of each genotype. On the basis of cluster analysis, four clusters were identified at a similarity level of 0.85. O. nivara, O. rufipogon and O. sativa with AA genomes constituted the first cluster. The second cluster comprised O. punctata of BB genome and wild rice species of CC genome i.e., O. rhizomatis and O. officinalis. However, it also contained O. barthii and O. glumaepatula of AA genome. O. australiensis with EE genome, and O. latifolia, O. alta and O. grandiglumis having CCDD genomes comprised the third cluster. The fourth cluster consisted of wild rice species, O. brachyantha with EE genome along with two other wild rice species, O. longistaminata and O. meridionalis of AA genome. Overall, on the basis of total seed protein, the grouping pattern of rice genotypes was mostly compatible with their genome status. The results of the present work depicted considerable interspecific genetic variation in the investigated germplasm for total seed protein. Moreover, the results obtained in this study also suggest that analysis of seed protein can also provide a better understanding of genetic affinity of the germplasm. (author)

  4. Studies on changes in fatty acid composition and content of endogenous antioxidants during gamma irradiation of rice seeds

    International Nuclear Information System (INIS)

    Ramarathnam, N.; Osawa, T.; Namiki, M.; Kawakishi, S.

    1989-01-01

    Accelerated aging effects, induced by y irradiation, were investigated on the fatty acid composition of lipids and on the content of endogenous antioxidants of four Indica and four Japonica rice seeds with and without intact hull. While the linoleic acid content of the phospholipids decreased gradually with the increase in irradiation doses, there was a corresponding increase in the linoleic acid content of the free fatty acids. Such changes were drastic, especially in the case of Japonica rice seeds irradiated without intact hull. However, the neutral lipids were found to be resistant to γ irradiation. The α-tocopherol content was found to decrease (markedly) in rice seeds irradiated with or without hull, especially in the Japonica rice seeds. At a dose of 15 kGy only traces of a-tocopherol could be detected in Japonica and Indica rice seeds irradiated with and without intact hull. Oryzanol, a relatively weaker anti-oxidant, was found to be more resistant to oxidative damage than a-tocopherol. At 15 kGy, the oryzanol content ranged from 59 μg to 170 μg/g lipid in rice seeds irradiated with intact hull, while the corresponding value for rice seeds irradiated without hull was 52 μg to 153 μg/g lipid. The overall susceptibility to oxidative damage was less in Indica rice seeds, indicating that the antioxidative defense system offered better protection in overcoming oxidative stress in Indica rice hull than in Japonica rice hull

  5. Mutagenic effects of heavy ion irradiation on rice seeds

    International Nuclear Information System (INIS)

    Xu Xue; Liu Binmei; Zhang Lili; Wu Yuejin

    2012-01-01

    Three varieties of rice seeds were subjected to irradiation using low-energy and medium-energy ions. The damage and mutations induced by the ions were examined. In addition, genetic analysis and gene mapping of spotted leaf (spl) mutants were performed. Low-energy ions had no significant influence on germination, survival or seedling height, except for the survival of Nipponbare. Medium-energy ions had a significant influence on germination and survival but had no significant effect on seedling height. In the low-energy group, among 60,000 M 2 plants, 2823 putative morphological mutants were found, and the mutation frequency was approximately 4.71%. In the medium-energy group, 3132 putative morphological mutants were found, and the mutation frequency was approximately 5.22%. Five spl mutants (spl29–spl33) were obtained by ion irradiation, and the heredity of the spl mutants was stable. The characteristics of the spl mutants were found, by genetic analysis and preliminary mapping, to be controlled by a single recessive gene, and spl30 and spl33 were found to be new lesion-mimic mutants.

  6. Mutagenic effects of heavy ion irradiation on rice seeds

    Energy Technology Data Exchange (ETDEWEB)

    Xu Xue [School of Agronomy, Anhui Agricultural University, 130 Changjiang West Road, Hefei 230036 (China); Key Laboratory of Ion Beam Bio-Engineering, Institute of Technical Biology and Agriculture Engineering, 350 Shushanhu Road, Hefei 230031 (China); Liu Binmei; Zhang Lili [Key Laboratory of Ion Beam Bio-Engineering, Institute of Technical Biology and Agriculture Engineering, 350 Shushanhu Road, Hefei 230031 (China); Wu Yuejin, E-mail: yjwu@ipp.ac.cn [Key Laboratory of Ion Beam Bio-Engineering, Institute of Technical Biology and Agriculture Engineering, 350 Shushanhu Road, Hefei 230031 (China)

    2012-11-01

    Three varieties of rice seeds were subjected to irradiation using low-energy and medium-energy ions. The damage and mutations induced by the ions were examined. In addition, genetic analysis and gene mapping of spotted leaf (spl) mutants were performed. Low-energy ions had no significant influence on germination, survival or seedling height, except for the survival of Nipponbare. Medium-energy ions had a significant influence on germination and survival but had no significant effect on seedling height. In the low-energy group, among 60,000 M{sub 2} plants, 2823 putative morphological mutants were found, and the mutation frequency was approximately 4.71%. In the medium-energy group, 3132 putative morphological mutants were found, and the mutation frequency was approximately 5.22%. Five spl mutants (spl29-spl33) were obtained by ion irradiation, and the heredity of the spl mutants was stable. The characteristics of the spl mutants were found, by genetic analysis and preliminary mapping, to be controlled by a single recessive gene, and spl30 and spl33 were found to be new lesion-mimic mutants.

  7. Genotypic Differences in Growth and Physiological Responses to Transplanting and Direct Seeding Cultivation in Rice

    Directory of Open Access Journals (Sweden)

    Song Chen

    2009-06-01

    Full Text Available The field experiments were conducted to investigate the growth and physiological responses of six super hybrid rice combinations to two planting methods, transplanting (TP and direct seeding (DS during 2006–2007 and 2007–2008. The 1000-grain weight and number of tillers per plant at the early growth stage, the maximum quantum yield of PSII (Fv/Fm and transpiration rate (Tr were higher in DS plants than in TP ones, whereas the grain yield, number of panicles per square meter, seed setting rate, net photosynthetic rate (Pn and stomatal conductance were lower in DS plants. However, little difference was detected in number of grains per panicle, stem (shoot and leaf weight between the combinations in the two planting methods. The responses of plant growth and physiological traits to planting method differed greatly among the six combinations. In both planting methods, Chouyou 58 and Yongyou 6 had the highest and lowest panicle biomass and Pn, respectively. The higher yield of Chunyou 58 was associated with more numbers of panicles per square meter and grains per panicle in both planting methods. The results indicate that lower grain yield in DS relative to TP is attributed to more excessive tillers at the early stage, lower leaf biomass and photosynthetic rate at the late stage.

  8. Utilization of wastewater on seed germination and physioogical parameters of rice (Oryza sativa L.)

    Science.gov (United States)

    Huy, V.; Iwai, C. B.

    2018-03-01

    Due to increasing world population and demand, fresh water availability is becoming a limited resource. Reusing wastewater for agriculture has received attention since it contains nutrients, which are beneficial for growing crops. Even though wastewater can be used as the nutrient source for the plant, the toxicity of wastewater can still be a cause for concern and investigation. The main objective of this paper was to assess the effect of different sources of wastewater on the germination of Jasmine rice (KDML105), White rice (Phatum Thani 1), and Sticky rice (RD6) under laboratory conditions. Petri dish cultures were used with various concentrations (0, 50, and 100%) of wastewater collected from swine farm, aquaculture activity, and domestic. Seed germination, root length, shoot length, seed vigor index, fresh weight and dry weight were measured after each experiment. The results have shown that domestic wastewater and aquaculture activity wastewater did not decrease performance of Jasmine rice (KDML105), White rice (Phatum thani 1), and Sticky rice (RD6) while the germination of Jasmine rice (KDML105), White rice (Phatum thani 1), and Sticky rice (RD6) decreased when irrigated with swine farm wastewater. Therefore, using domestic and aquaculture activity wastewater for irrigation are suitable for growth of these crop.

  9. Genes controlling seed dormancy and pre-harvest sprouting in a rice-wheat-barley comparison

    DEFF Research Database (Denmark)

    Li, Chengdao; Ni, Peixiang; Francki, Michael

    2004-01-01

    Pre-harvest sprouting results in significant economic loss for the grain industry around the world. Lack of adequate seed dormancy is the major reason for pre-harvest sprouting in the field under wet weather conditions. Although this trait is governed by multiple genes it is also highly heritable....... A major QTL controlling both pre-harvest sprouting and seed dormancy has been identified on the long arm of barley chromosome 5H, and it explains over 70% of the phenotypic variation. Comparative genomics approaches among barley, wheat and rice were used to identify candidate gene(s) controlling seed...... dormancy and hence one aspect of pre-harvest sprouting. The barley seed dormancy/pre-harvest sprouting QTL was located in a region that showed good synteny with the terminal end of the long arm of rice chromosome 3. The rice DNA sequences were annotated and a gene encoding GA20-oxidase was identified...

  10. DNA comet assay for rice seeds treated with low energy electrons ('soft-electrons')

    International Nuclear Information System (INIS)

    Todoriki, Setsuko; Hayashi, Toru

    1999-01-01

    As rice seeds are sometimes contaminated with phytopathogenic organisms such as blast disease fungi and nematodes, a novel non-chemical disinfection method for rice seeds is highly required. In order to develop a disinfection method, the effect of low energy electron ('soft-electrons') on seed DNA was examined by using the neutral comet assay. Rice seeds (whole grain) were treated with electrons of different acceleration voltages (180 kV to 1 MV) at a dose of 5 kGy. Nucleus suspensions were prepared from whole brown rice and subjected to electrophoresis. DNA from un-irradiated (control) seeds relaxed and produced comets with a short tail, most of the comets distributed within the range of comet length between 30 μm to 70 μm. In the case of seeds treated with electrons at acceleration voltages up to 190 kV, cells without seed coats were not damaged and the frequency histograms of comet length showed almost the same pattern as that for control. At acceleration voltages higher than 200 kV, the cells were distributed into two categories; DNA comets with a short tail (with little DNA damages, less than 70 μm in the comet length) and DNA comets with long tails (with sever strand breaks, more than 130 μm in the comet length). The ratios of damaged cells increased with increasing acceleration voltage. The growths of rice seedlings were not affected by the treatment with electrons at up to 200 kV. On the contrary, the cells of gamma-irradiated seed showed small variations in the comet length, and which were depending on radiation dose. The individual cells of gamma-irradiated seeds at 1 kGy showed shorter comet than the damaged cells with soft electron, seed treated with gamma rays (1-5 kGy) did not shoot nor root. (author)

  11. Banco de sementes de arroz vermelho em sistemas de semeadura de arroz irrigado Red rice seed bank under seeding systems of flooded rice

    Directory of Open Access Journals (Sweden)

    Luis Antonio de Avila

    2000-10-01

    Full Text Available O experimento foi conduzido com o objetivo de estimar a variação do banco de sementes viáveis de arroz vermelho (Oryza sativa L., em três sistemas de semeadura de arroz (O. sativa L. irrigado (semeadura convencional, direta e com sementes pré-germinadas, após três anos de cultivo na mesma área, em São Borja, RS, em solo classificado como Planossolo, com infestação média de 150 plantas de arroz vermelho por m² antes da instalação do experimento. A coleta do solo para estimativa do banco de sementes de arroz vermelho foi realizada com um trado cilíndrico de metal de 10cm de diâmetro. Foram realizadas amostragens de solo, com 12 amostras por parcela em duas profundidades (0-1cm e 1-10cm, para retirar os grãos de arroz vermelho, submetê-los ao teste de tetrazólio e determinar sua viabilidade. O experimento foi um bifatorial em blocos ao acaso, com três repetições, com os sistemas de semeadura de arroz como fator principal e as profundidades de coleta como fator secundário. Os dados demonstraram que o número de sementes viáveis de arroz vermelho no solo foi maior na área onde o arroz foi cultivado no sistema de semeadura convencional (1994 sementes/m², com valores intermediários para o sistema de semeadura direta (597 sementes/m² e menores valores para o sistema de semeadura com sementes pré-germinadas (93 sementes/m². Assim, demonstra-se que a semeadura de arroz no sistema de sementes pré-germinadas favorece o controle do arroz vermelho, mantendo a quantidade de sementes em densidades menores do que nos sistemas de semeadura direta e convencional.An experiment was conducted aiming to estimate the variability of viable seeds of red rice (Oryza sativa L. in soil under three rice (O. sativa L. seeding systems: conventional, no-tillage and water seeded. It was located in São Borja, Rio Grande do Sul state, Brazil, in an albaqualf soil with an average of 150 red rice plants per square meter before establishing the

  12. Comparison of Rice Direct Seeding Methods (Mechanical and Manual with Transplanting Method

    Directory of Open Access Journals (Sweden)

    A Eyvani

    2014-04-01

    Full Text Available The main method of rice planting in Iran is transplanting. Due to poor mechanization of rice production, this method is laborious and costly. The other method is direct seeding in wet lands which is performed in the one third of rice cultivation area of the world. The most important problem in this method is high labor requirement of weed control. In order to compare the different rice planting methods (direct drilling, transplanting, and seed broadcasting a manually operated rice direct seeder (drum seeder was designed and fabricated. The research was conducted using a randomized complete block design with three treatments and three replications. Required draft force, field efficiency, effective field capacity, yield, and yield components were measured and the treatments were compared economically. Results showed that there were significant differences among the treatments from the view point of rice yield at the confidence level of 95% i.e. the transplanting method had the maximum yield. A higher rice yield was obtained from the direct seeder compared to the manual broadcasting method but, the difference between these two methods for crop yield was not significant even at the confidence level of the 95%. The coefficient of variation of seed distribution with direct seeding was more than 20%. The labor and time requirements per hectare reduced to 7 and 20 times, respectively when comparing the newly designed direct seeder with the transplanting method. The direct seeding method had the highest benefit to cost ratio in spite of its lower yield. Therefore, this method could be recommended in the rice growing regions.

  13. Physiological and biochemical mechanisms of seed priming-induced chilling tolerance in rice cultivars

    Directory of Open Access Journals (Sweden)

    Saddam eHussain

    2016-02-01

    Full Text Available Rice belongs to tropical and subtropical environments and is extremely sensitive to chilling stress particularly during emergence and early stages of seedling development. Seed priming can be a good approach to enhance rice germination and stand establishment under chilling stress. The present study examined the role of different seed priming techniques viz., hydropriming, osmopriming, redox priming, chemical priming, and hormonal priming, in enhancing the chilling tolerance in rice. The most effective reagents and their pre-optimized concentrations based on preliminary experiments were used in this study. Two different rice cultivars were sown under chilling stress (18˚C and normal temperatures (28˚C in separate growth chambers. A non-primed control treatment was also maintained for comparison. Chilling stress caused erratic and delayed germination, poor seedling growth, reduced starch metabolism and lower respiration rate, while higher lipid peroxidation and hydrogen peroxide accumulation in rice seedlings of both cultivars. Nevertheless, all the seed priming treatments effectively alleviated the negative effects of chilling stress. In addition, seed priming treatments triggered the activities of superoxide dismutase, peroxidase, and catalase, and enhanced the accumulations of glutathione and free proline in rice seedlings, which suggests that these measures help prevent the rice seedlings from chilling induced oxidative stress. Chemical priming with selenium and hormonal priming with salicylic acid remained more effective treatments for both rice cultivars under chilling stress than all other priming treatments. The better performance and greater tolerance of primed rice seedlings was associated with enhanced starch metabolism, high respiration rate, lower lipid peroxidation, and strong antioxidative defense system under chilling stress.

  14. Estimation of loci involved in non-shattering of seeds in early rice domestication.

    Science.gov (United States)

    Ishikawa, Ryo; Nishimura, Akinori; Htun, Than Myint; Nishioka, Ryo; Oka, Yumi; Tsujimura, Yuki; Inoue, Chizuru; Ishii, Takashige

    2017-04-01

    Rice (Oryza sativa L.) is widely cultivated around the world and is known to be domesticated from its wild form, O. rufipogon. A loss of seed shattering is one of the most obvious phenotypic changes selected for during rice domestication. Previously, three seed-shattering loci, qSH1, sh4, and qSH3 were reported to be involved in non-shattering of seeds of Japonica-type cultivated rice, O. sativa cv. Nipponbare. In this study, we focused on non-shattering characteristics of O. sativa Indica cv. IR36 having functional allele at qSH1. We produced backcross recombinant inbred lines having chromosomal segments from IR36 in the genetic background of wild rice, O. rufipogon W630. Histological and quantitative trait loci analyses of abscission layer formation were conducted. In the analysis of quantitative trait loci, a strong peak was observed close to sh4. We, nevertheless, found that some lines showed complete abscission layer formation despite carrying the IR36 allele at sh4, implying that non-shattering of seeds of IR36 could be regulated by the combination of mutations at sh4 and other seed-shattering loci. We also genotyped qSH3, a recently identified seed-shattering locus. Lines that have the IR36 alleles at sh4 and qSH3 showed inhibition of abscission layer formation but the degree of seed shattering was different from that of IR36. On the basis of these results, we estimated that non-shattering of seeds in early rice domestication involved mutations in at least three loci, and these genetic materials produced in this study may help to identify novel seed-shattering loci.

  15. Production of Biologically Active Cecropin A Peptide in Rice Seed Oil Bodies.

    Directory of Open Access Journals (Sweden)

    Laura Montesinos

    Full Text Available Cecropin A is a natural antimicrobial peptide that exhibits fast and potent activity against a broad spectrum of pathogens and neoplastic cells, and that has important biotechnological applications. However, cecropin A exploitation, as for other antimicrobial peptides, is limited by their production and purification costs. Here, we report the efficient production of this bioactive peptide in rice bran using the rice oleosin 18 as a carrier protein. High cecropin A levels were reached in rice seeds driving the expression of the chimeric gene by the strong embryo-specific oleosin 18 own promoter, and targeting the peptide to the oil body organelle as an oleosin 18-cecropin A fusion protein. The accumulation of cecropin A in oil bodies had no deleterious effects on seed viability and seedling growth, as well as on seed yield. We also show that biologically active cecropin A can be easily purified from the transgenic rice seeds by homogenization and simple flotation centrifugation methods. Our results demonstrate that the oleosin fusion technology is suitable for the production of cecropin A in rice seeds, which can potentially be extended to other antimicrobial peptides to assist their exploitation.

  16. Genetic control of a transition from black to straw-white seed hull in rice domestication.

    Science.gov (United States)

    Zhu, Bo-Feng; Si, Lizhen; Wang, Zixuan; Zhou, Yan; Zhu, Jinjie; Shangguan, Yingying; Lu, Danfeng; Fan, Danlin; Li, Canyang; Lin, Hongxuan; Qian, Qian; Sang, Tao; Zhou, Bo; Minobe, Yuzo; Han, Bin

    2011-03-01

    The genetic mechanism involved in a transition from the black-colored seed hull of the ancestral wild rice (Oryza rufipogon and Oryza nivara) to the straw-white seed hull of cultivated rice (Oryza sativa) during grain ripening remains unknown. We report that the black hull of O. rufipogon was controlled by the Black hull4 (Bh4) gene, which was fine-mapped to an 8.8-kb region on rice chromosome 4 using a cross between O. rufipogon W1943 (black hull) and O. sativa indica cv Guangluai 4 (straw-white hull). Bh4 encodes an amino acid transporter. A 22-bp deletion within exon 3 of the bh4 variant disrupted the Bh4 function, leading to the straw-white hull in cultivated rice. Transgenic study indicated that Bh4 could restore the black pigment on hulls in cv Guangluai 4 and Kasalath. Bh4 sequence alignment of all taxa with the outgroup Oryza barthii showed that the wild rice maintained comparable levels of nucleotide diversity that were about 70 times higher than those in the cultivated rice. The results from the maximum likelihood Hudson-Kreitman-Aguade test suggested that the significant reduction in nucleotide diversity in rice cultivars could be caused by artificial selection. We propose that the straw-white hull was selected as an important visual phenotype of nonshattered grains during rice domestication.

  17. Effects of gamma rays and neutrons on the seedling and callus growth in rice seeds

    International Nuclear Information System (INIS)

    Baradjanegara, A.A.; Fujii, T.; Amano, E.

    1976-01-01

    Seeds of rice c.v. Norin-8 and two radiation induced dwarf mutants MGS-46 and -96 were used to investigate the effects of gamma and 14 MeV neutron-radiations in different culture systems. Seeding growth of irradiated seeds in soil, and in two types of synthetic media, modified White's (M-W) or modified Erickson's (M-E), as well as the callus growth on 2,4-D supplemented media were measured as an index radiation damage. Comparing the seeding height about two types of media, the M-E promoted the plant growth than the M-W in irradiated as well as non irradiated lots of the three strains studied. The callus growth on M-E surpassed by more 10 times that obtained on the M-W in all the lots. The M-E medium seems to be appropriate for both the seeding and callus growth of rice. (author)

  18. Effects of cobalt-60 low doses radiation on beam, rice and radish seeds

    International Nuclear Information System (INIS)

    Kikuchi, O.K.

    1987-01-01

    The effects of cobalt-60 gamma radiation on seeds of bean (Phaseolus vulgaris L.), rice (Oryza sativa L.) and radish (Raphanus sativus L.) were studied. Bean and rice seeds were irradiated with 3.5 and 7.7 Gy (32 Gy/h). There was an apparent acceleration on rice seed germination with 3.5 Gy when they were stored for 6 days after irradiation, but the same dose caused a delay when the store time was 1 day. Bean seeds germination was not modified by 3.5 and 7.7 Gy, but the fresh and dry weight of young plants showed an increase, mainly due the major quantity of water in the embryonic axis. Bean seeds were irradiated with 0.5 and 2.0 Gy (30 Gy/h). Seeds germination showed a slight delay irradiating with 0.5 Gy, while height, fresh and dry weight and primary leaves area of the young plants as well as number of nodes, leaves, flowers, beans and seeds were not modified after irradiation with 0.5 and 2.0 Gy. Radish seeds irradiated with 10 and 30 Gy at dose rates of 4.5, 22.5 and 45.0 Gy/h showed a germination delay and fresh and dry weight values for young plants leaves lower than control. Roots of totally developed plants showed no modifications in weight, volume, mean diameter, lenght and in the amount of soluble reducing sugar. (author)

  19. RICE SEED TREATMENT AND RECOATING WITH POLYMERS: PHYSIOLOGICAL QUALITY AND RETENTION OF CHEMICAL PRODUCTS

    Directory of Open Access Journals (Sweden)

    LOVANE KLEIN FAGUNDES

    2017-01-01

    Full Text Available The use of chemical seed treatment is an important tool in the protection of seedlings and has contributed to the increase of rice yield (Oryza sativa L.. The objective of this study was to evaluate the physiological quality and quantify the retention of chemical products in rice seeds treated with insecticide and fungicide coated with polymers. Six seed treatments were used: control, phytosanitary treatment and phytosanitary treatment and coating with the polymers, Florite 1127®, GV5® Solid Resin, Polyseed CF® and VermDynaseed®. The physiological quality was evaluated by the test of germination and vigor by first count tests, germination speed index, shoot length, radicle length, seedling dry mass and sand emergence. To determine the retention of the active ingredients metalaxyl-M and thiamethoxam, an equipment called extractor was used. The experiment was organized in a completely randomized design (DIC and the averages were separated by the Scott Knott test (p≤0.05. Seed treatment with the fungicide and insecticide, coated with the polymers, Florite 1127®, Solid Resin GV5®, Polyseed CF® and VermDynaseed®, did not affect the physiological quality of rice seeds. Solid Resin GV5®, Polyseed CF® and VermDynaseed® polymers were efficient at retaining thiamethoxam in the rice seeds, preventing some of the active ingredients of the insecticide from being leached through the sand columns immediately after the simulated pluvial precipitation.

  20. Laccase-13 Regulates Seed Setting Rate by Affecting Hydrogen Peroxide Dynamics and Mitochondrial Integrity in Rice

    Directory of Open Access Journals (Sweden)

    Yang Yu

    2017-07-01

    Full Text Available Seed setting rate is one of the most important components of rice grain yield. To date, only several genes regulating setting rate have been identified in plant. In this study, we showed that laccase-13 (OsLAC13, a member of laccase family genes which are known for their roles in modulating phenylpropanoid pathway and secondary lignification in cell wall, exerts a regulatory function in rice seed setting rate. OsLAC13 expressed in anthers and promotes hydrogen peroxide production both in vitro and in the filaments and anther connectives. Knock-out of OsLAC13 showed significantly increased seed setting rate, while overexpression of this gene exhibited induced mitochondrial damage and suppressed sugar transportation in anthers, which in turn affected seed setting rate. OsLAC13 also induced H2O2 production and mitochondrial damage in the root tip cells which caused the lethal phenotype. We also showed that high abundant of OsmiR397, the suppressor of OsLAC13 mRNA, increased the seed setting rate of rice plants, and restrains H2O2 accumulation in roots during oxidative stress. Our results suggested a novel regulatory role of OsLAC13 gene in regulating seed setting rate by affecting H2O2 dynamics and mitochondrial integrity in rice.

  1. Effect of Weed Management and Seed Rate on Crop Growth under Direct Dry Seeded Rice Systems in Bangladesh

    Science.gov (United States)

    Ahmed, Sharif; Salim, Muhammad; Chauhan, Bhagirath S.

    2014-01-01

    Weeds are a major constraint to the success of dry-seeded rice (DSR). The main means of managing these in a DSR system is through chemical weed control using herbicides. However, the use of herbicides alone may not be sustainable in the long term. Approaches that aim for high crop competitiveness therefore need to be exploited. One such approach is the use of high rice seeding rates. Experiments were conducted in the aman (wet) seasons of 2012 and 2013 in Bangladesh to evaluate the effect of weed infestation level (partially-weedy and weed-free) and rice seeding rate (20, 40, 60, 80, and 100 kg ha−1) on weed and crop growth in DSR. Under weed-free conditions, higher crop yields (5.1 and 5.2 t ha−1 in the 2012 and 2013 seasons, respectively) were obtained at the seeding rate of 40 kg ha−1 and thereafter, yield decreased slightly beyond 40 kg seed ha−1. Under partially-weedy conditions, yield increased by 30 to 33% (2.0–2.2 and 2.9–3.2 t ha−1 in the 2012 and 2013 seasons, respectively) with increase in seeding rate from 20 to 100 kg ha−1. In the partially-weedy plots, weed biomass decreased by 41–60% and 54–56% at 35 days after sowing and at crop anthesis, respectively, when seeding rate increased from 20 to 100 kg ha−1. Results from our study suggest that increasing seeding rates in DSR can suppress weed growth and reduce grain yield losses from weed competition. PMID:25000520

  2. Effect of weed management and seed rate on crop growth under direct dry seeded rice systems in Bangladesh.

    Directory of Open Access Journals (Sweden)

    Sharif Ahmed

    Full Text Available Weeds are a major constraint to the success of dry-seeded rice (DSR. The main means of managing these in a DSR system is through chemical weed control using herbicides. However, the use of herbicides alone may not be sustainable in the long term. Approaches that aim for high crop competitiveness therefore need to be exploited. One such approach is the use of high rice seeding rates. Experiments were conducted in the aman (wet seasons of 2012 and 2013 in Bangladesh to evaluate the effect of weed infestation level (partially-weedy and weed-free and rice seeding rate (20, 40, 60, 80, and 100 kg ha(-1 on weed and crop growth in DSR. Under weed-free conditions, higher crop yields (5.1 and 5.2 t ha(-1 in the 2012 and 2013 seasons, respectively were obtained at the seeding rate of 40 kg ha(-1 and thereafter, yield decreased slightly beyond 40 kg seed ha(-1. Under partially-weedy conditions, yield increased by 30 to 33% (2.0-2.2 and 2.9-3.2 t ha(-1 in the 2012 and 2013 seasons, respectively with increase in seeding rate from 20 to 100 kg ha(-1. In the partially-weedy plots, weed biomass decreased by 41-60% and 54-56% at 35 days after sowing and at crop anthesis, respectively, when seeding rate increased from 20 to 100 kg ha(-1. Results from our study suggest that increasing seeding rates in DSR can suppress weed growth and reduce grain yield losses from weed competition.

  3. Effect of weed management and seed rate on crop growth under direct dry seeded rice systems in Bangladesh.

    Science.gov (United States)

    Ahmed, Sharif; Salim, Muhammad; Chauhan, Bhagirath S

    2014-01-01

    Weeds are a major constraint to the success of dry-seeded rice (DSR). The main means of managing these in a DSR system is through chemical weed control using herbicides. However, the use of herbicides alone may not be sustainable in the long term. Approaches that aim for high crop competitiveness therefore need to be exploited. One such approach is the use of high rice seeding rates. Experiments were conducted in the aman (wet) seasons of 2012 and 2013 in Bangladesh to evaluate the effect of weed infestation level (partially-weedy and weed-free) and rice seeding rate (20, 40, 60, 80, and 100 kg ha(-1)) on weed and crop growth in DSR. Under weed-free conditions, higher crop yields (5.1 and 5.2 t ha(-1) in the 2012 and 2013 seasons, respectively) were obtained at the seeding rate of 40 kg ha(-1) and thereafter, yield decreased slightly beyond 40 kg seed ha(-1). Under partially-weedy conditions, yield increased by 30 to 33% (2.0-2.2 and 2.9-3.2 t ha(-1) in the 2012 and 2013 seasons, respectively) with increase in seeding rate from 20 to 100 kg ha(-1). In the partially-weedy plots, weed biomass decreased by 41-60% and 54-56% at 35 days after sowing and at crop anthesis, respectively, when seeding rate increased from 20 to 100 kg ha(-1). Results from our study suggest that increasing seeding rates in DSR can suppress weed growth and reduce grain yield losses from weed competition.

  4. Ammonia Volatilization from Urea-Application Influenced Germination and Early Seedling Growth of Dry Direct-Seeded Rice

    Directory of Open Access Journals (Sweden)

    Xiaoli Qi

    2012-01-01

    Full Text Available Poor seed germination and early seedling growth associated with urea-induced soil ammonia volatilization are major constraints in the adoption of dry direct-seeded rice. To directly examine soil ammonia volatilization and its damage to seed germination and early seedling growth of dry direct-seeded rice when urea is applied at seeding, two Petri-dish incubation experiments and a field experiment were conducted. Ammonia volatilization due to urea application significantly reduced seed germination and early seedling growth of dry direct-seedling rice. NBPT significantly reduced ammonia volatilization following urea application. The application of ammonium sulfate, instead of urea at seeding, may mitigate poor crop establishment of dry direct-seeded rice. Root growth of dry direct-seeded rice was more seriously inhibited by soil ammonia volatilization than that of shoot. Results suggest that roots are more sensitive to soil ammonia toxicity than shoots in dry direct-seeded rice system when N is applied as urea at seeding.

  5. Induction of antioxidant enzyme activity and lipid peroxidation level in ion-beam-bombarded rice seeds

    Energy Technology Data Exchange (ETDEWEB)

    Semsang, Nuananong, E-mail: nsemsang@gmail.com [Molecular Biology Laboratory, Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, LiangDeng [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

    2013-07-15

    Highlights: ► Ion beam bombarded rice seeds in vacuum. ► Studied seed survival from the ion bombardment. ► Determined various antioxidant enzyme activities and lipid peroxidation level. ► Discussed vacuum, ion species and ion energy effects. ► Attributed the changes to free radical formation due to ion bombardment. -- Abstract: Low-energy ion beam bombardment has been used to mutate a wide variety of plant species. To explore the indirect effects of low-energy ion beam on biological damage due to the free radical production in plant cells, the increase in antioxidant enzyme activities and lipid peroxidation level was investigated in ion-bombarded rice seeds. Local rice seeds were bombarded with nitrogen or argon ion beams at energies of 29–60 keV and ion fluences of 1 × 10{sup 16} ions cm{sup −2}. The activities of the antioxidant enzymes; superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione S-transferase (GST) and lipid peroxidation level were assayed in the germinated rice seeds after ion bombardment. The results showed most of the enzyme activities and lipid peroxidation levels in both the argon and nitrogen bombarded samples were higher than those in the natural control. N-ion bombardment could induce higher levels of antioxidant enzyme activities in the rice samples than the Ar-ion bombardment. Additional effects due to the vacuum condition were found to affect activities of some antioxidant enzymes and lipid peroxidation level. This study demonstrates that ion beam bombardment and vacuum condition could induce the antioxidant enzyme activity and lipid peroxidation level which might be due to free radical production in the bombarded rice seeds.

  6. Rice and foxtail millet cultivation reconstructed from weed seed assemblages in the Chengtoushan site, central China

    International Nuclear Information System (INIS)

    Nasu, H.; Yasuda, Y.; Momohara, A.; Jiejun, H.

    2005-01-01

    Full text: Crop weeds have been successfully used for evaluation of farming practices in archaeological sites and reconstruction of the environmental condition. In rice agricultural sites in East Asia, however, a few studies of crop remains have been attempted. We evaluated the crop husbandry based on plant macrofossils including crop grains and weed seeds in the Chengtoushan site, Hunan Province, central China, which is one of the oldest rice agricultural site around the Yangtze River Basin. In the moat surrounding the site that is located on a loess plateau that juts out into the alluvial plain, we recognized three cultural layers during the Daxi Culture. Plant macrofossils in silty clay deposits in the moat consist of abundant rice and foxtail millet grains with many weed seeds. Radiocarbon age of these fossils shows that rice and foxtail millet cultivation dated back to 6400 cal. years B.P. The weed seed composition characterizes farmland and ruderal environments in the site surrounded by the moat. We assumed foxtail millet and rice cultivation practiced within the site on loess plateau, along with a paddy style rice cultivation in the alluvial lowland outside of the site. (author)

  7. Induction of antioxidant enzyme activity and lipid peroxidation level in ion-beam-bombarded rice seeds

    Science.gov (United States)

    Semsang, Nuananong; Yu, LiangDeng

    2013-07-01

    Low-energy ion beam bombardment has been used to mutate a wide variety of plant species. To explore the indirect effects of low-energy ion beam on biological damage due to the free radical production in plant cells, the increase in antioxidant enzyme activities and lipid peroxidation level was investigated in ion-bombarded rice seeds. Local rice seeds were bombarded with nitrogen or argon ion beams at energies of 29-60 keV and ion fluences of 1 × 1016 ions cm-2. The activities of the antioxidant enzymes; superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione S-transferase (GST) and lipid peroxidation level were assayed in the germinated rice seeds after ion bombardment. The results showed most of the enzyme activities and lipid peroxidation levels in both the argon and nitrogen bombarded samples were higher than those in the natural control. N-ion bombardment could induce higher levels of antioxidant enzyme activities in the rice samples than the Ar-ion bombardment. Additional effects due to the vacuum condition were found to affect activities of some antioxidant enzymes and lipid peroxidation level. This study demonstrates that ion beam bombardment and vacuum condition could induce the antioxidant enzyme activity and lipid peroxidation level which might be due to free radical production in the bombarded rice seeds.

  8. Different Aluminum Tolerance among Indica, Japonica and Hybrid Rice Varieties

    Directory of Open Access Journals (Sweden)

    Shu Chang

    2015-05-01

    Full Text Available Hydroponic cultures were conducted to compare the aluminum (Al tolerance among different rice (Oryza sativa L. varieties, including indica, japonica and their hybrids. The results showed that the root growth of rice plant was inhibited in different degrees among Al treated varieties. The Al tolerance observed through relative root elongation indicated that five japonica varieties including Longjing 9, Dharial, LGC 1, Ribenyou and Koshihikari were relatively more tolerant than indica varieties. Most indica varieties in this study, such as Aus 373 and 9311 (awnless, were sensitive to Al toxicity. The Al tolerance of most progenies from japonica × indica or indica × japonica crosses was constantly consistent with indica parents. The differences of Al tolerance among Longjing 9 (japonica, Yangdao 6 (indica and Wuyunjing 7 (japonica were studied. Biomass and the malondial-dehyde content of Yangdao 6 under Al exposure decreased and increased, respectively, while there was no significant effect on those of Longjing 9 and Wuyunjing 7. Remarkable reduction of root activities was observed in all these three rice varieties. Significantly higher Al content in roots was found in Yangdao 6 compared to Longjing 9 or Wuyunjing 7.

  9. Involvement of Polyamine Oxidase-Produced Hydrogen Peroxide during Coleorhiza-Limited Germination of Rice Seeds

    Directory of Open Access Journals (Sweden)

    Bing-Xian Chen

    2016-08-01

    Full Text Available Seed germination is a complicated biological process that requires regulated enzymatic and non-enzymatic reactions. The action of polyamine oxidase (PAO produces hydrogen peroxide (H2O2, which promotes dicot seed germination. However, whether and, if so, how PAOs regulate monocot seed germination via H2O2 production is unclear. Herein, we report that the coleorhiza is the main physical barrier to radicle protrusion during germination of rice seed (a monocot seed and that it does so in a manner similar to that of dicot seed micropylar endosperm. We found that H2O2 specifically and steadily accumulated in the coleorhizae and radicles of germinating rice seeds and was accompanied by increased PAO activity as the germination percentage increased. These physiological indexes were strongly decreased in number by guazatine, a PAO inhibitor. We also identified 11 PAO homologs (OsPAO1–11 in the rice genome, which could be classified into four subfamilies (I, IIa, IIb, and III. The OsPAO genes in subfamilies I, IIa, and IIb (OsPAO1–7 encode PAOs, whereas those in subfamily III (OsPAO8–11 encode histone lysine-specific demethylases. In silico-characterized expression profiles of OsPAO1–7 and those determined by qPCR revealed that OsPAO5 is markedly upregulated in imbibed seeds compared with dry seeds and that its transcript accumulated to a higher level in embryos than in the endosperm. Moreover, its transcriptional abundance increased gradually during seed germination in water and was inhibited by 5 mM guazatine. Taken together, these results suggest that PAO-generated H2O2 is involved in coleorhiza-limited rice seed germination and that OsPAO5 expression accounts for most PAO expression and activity during rice seed germination. These findings should facilitate further study of PAOs and provide valuable information for functional validation of these proteins during seed germination of monocot cereals.

  10. Improving restorer line of hybrid rice by irradiation

    International Nuclear Information System (INIS)

    Guo Guangrong; Yi Weiping; Liu Wuquan

    1995-03-01

    The work for improving restorer line of hybrid rice has been done. The results showed the radiosensitivity of foreign varieties overtakes Chinese ones at average level. Because of their different blood relationship, there are various situation on foreign varieties, i.e. varieties from IR system are not sensitive, Shui-yun system are second and Miyang system are sensitive. The radiosensitivity for restorer lines of hybrid F 0 overtakes one for F 1 . According to this results. We have put forward the point of view 'Multi-gene type blend system'. M 2 mutant frequency of restorer line was investigated. The results showed: there was a little difference between the total mutant frequencies from the different varieties. But, there may be difference in some characters by over thirty times between them. So a problem, worthy to be further studied is proposed that do the differences of radiosensitivity between varieties relate to the mutant frequency of these characters? Various mutants were obtained by irradiation treatment, among which a few mutants changed to maintainer line because losing restorer genes, other more mutants still were restorer lines. New combinations developed by these new mutant restorer lines have strong heterosis. The optimum combinations have been utilized in rice production. (7 tabs.)

  11. The knockdown of OsVIT2 and MIT affects iron localization in rice seed.

    Science.gov (United States)

    Bashir, Khurram; Takahashi, Ryuichi; Akhtar, Shamim; Ishimaru, Yasuhiro; Nakanishi, Hiromi; Nishizawa, Naoko K

    2013-11-20

    The mechanism of iron (Fe) uptake in plants has been extensively characterized, but little is known about how Fe transport to different subcellular compartments affects Fe localization in rice seed. Here, we discuss the characterization of a rice vacuolar Fe transporter 2 (OsVIT2) T-DNA insertion line (osvit2) and report that the knockdown of OsVIT2 and mitochondrial Fe transporter (MIT) expression affects seed Fe localization. osvit2 plants accumulated less Fe in their shoots when grown under normal or excess Fe conditions, while the accumulation of Fe was comparable to that in wild-type (WT) plants under Fe-deficient conditions. The accumulation of zinc, copper, and manganese also changed significantly in the shoots of osvit2 plants. The growth of osvit2 plants was also slow compared to that of WT plants. The concentration of Fe increased in osvit2 polished seeds. Previously, we reported that the expression of OsVIT2 was higher in MIT knockdown (mit-2) plants, and in this study, the accumulation of Fe in mit-2 seeds decreased significantly. These results suggest that vacuolar Fe trafficking is important for plant Fe homeostasis and distribution, especially in plants grown in the presence of excess Fe. Moreover, changes in the expression of OsVIT2 and MIT affect the concentration and localization of metals in brown rice as well as in polished rice seeds.

  12. Enhancement of Salinity Tolerance during Rice Seed Germination by Presoaking with Hemoglobin

    Directory of Open Access Journals (Sweden)

    Sheng Xu

    2011-04-01

    Full Text Available Salinity stress is an important environmental constraint limiting the productivity of many crops worldwide. In this report, experiments were conducted to investigate the effects of seed presoaking by bovine hemoglobin, an inducer of heme oxygenase-1 (HO-1, on salinity tolerance in rice (Oryza sativa plants. The results showed that different concentrations of the hemoglobin (0.01, 0.05, 0.2, 1.0, and 5.0 g/L differentially alleviated the inhibition of rice seed germination and thereafter seedling shoot growth caused by 100 mM NaCl stress, and the responses of 1.0 g/L hemoglobin was the most obvious. Further analyses showed that application of hemoglobin not only increased the HO-1 gene expression, but also differentially induced catalase (CAT, ascorbate peroxidase (APX, and superoxide dismutase (SOD activities or transcripts, thus decreasing the lipid peroxidation in germinating rice seeds subjected to salt stress. Compared with non-hemoglobin treatment, hemoglobin presoaking also increased the potassium (K to sodium (Na ratio both in the root and shoot parts after salinity stress. The effect is specific for HO-1 since the potent HO-1 inhibitor zinc protoporphyrin IX (ZnPPIX blocked the positive actions of hemoglobin on seed germination and seedling shoot growth. Overall, these results suggested that hemoglobin performs an advantageous role in enhancement of salinity tolerance during rice seed germination.

  13. M1 chimerism following mutagen treatment of seeds in rice and some other cereals

    International Nuclear Information System (INIS)

    Kawai, T.

    1983-01-01

    Articles reporting on M 1 chimerism following treatment of seed with mutagen in cereals were mostly published in the 1960's. Rice is a good material for making such studies because of its relatively large number of seeds per panicle, rather easily identifiable tillering and panicle branching systems and uniform growth after seedling transplanting. The present article summarizes results of studies on M 1 chimerism in rice and some other cereals which may serve as reference information in discussing M 1 chimerism of those plant species showing different development patterns, as dicotyledonous plants, following treatment of seed with mutagen. Studies on M 1 chimerism provide not only knowledge of the sporophyte development but also basic information for developing methods of harvesting M 2 seed which provide the maximum numbers of mutants of different origins in a limited number of M 2 plants. (author)

  14. Yield and tillering response of super hybrid rice Liangyoupeijiu to tillage and establishment methods

    Directory of Open Access Journals (Sweden)

    M.A. Badshah

    2014-02-01

    Full Text Available Tillering is an important agronomic trait for rice grain production. To evaluate yield and tillering response, Liangyoupeijiu (super hybrid rice was grown in Hunan, China during 2011–2012 under different methods of tillage (conventional and no-tillage system and crop establishment methods (transplanting at a spacing of 20 cm × 20 cm with one seedling per hill and direct seeding at a seeding rate of 22.5 kg ha− 1. Our results revealed that, at maximum tillering (Max. and at maturity (MA stages, direct seeding (DS resulted in 22% more tillers than transplanting (TP irrespective of tillage system. Tiller mortality reached a peak between panicle initiation (PI and booting (BT stages, and was 16% higher under conventional tillage (CT than under no-tillage (NT. Transplanting required 29% more time for the completion of tillering and less for DS. Tillering rate was 43% higher in DS than TP under either CT or NT. There was a positive correlation between panicle number per m2 and maximum tiller number per m2, but not panicle-bearing tiller rate. The panicle bearing tiller rate was higher under DS than TP and higher under NT than CT. Tiller dry weight gradually increased up to heading (HD stage, and was 14% higher under TP than DS. Leaf area (cm2 tiller− 1 gradually increased from Max. to HD stage and then decreased by 34% in conventional tillage transplanting (CTTP and 45% in no-tillage transplanting (NTTP from 12DAH–24DAH (days after heading, but was similar (35% under DS under either CT or NT. Grain yield was higher under CTTP owing to the larger sink size (heavier panicle, more spikelets in per cm length of panicle than under DS.

  15. Salinity Inhibits Rice Seed Germination by Reducing α-Amylase Activity via Decreased Bioactive Gibberellin Content

    Directory of Open Access Journals (Sweden)

    Li Liu

    2018-03-01

    Full Text Available Seed germination plays important roles in the establishment of seedlings and their subsequent growth; however, seed germination is inhibited by salinity, and the inhibitory mechanism remains elusive. Our results indicate that NaCl treatment inhibits rice seed germination by decreasing the contents of bioactive gibberellins (GAs, such as GA1 and GA4, and that this inhibition can be rescued by exogenous bioactive GA application. To explore the mechanism of bioactive GA deficiency, the effect of NaCl on GA metabolic gene expression was investigated, revealing that expression of both GA biosynthetic genes and GA-inactivated genes was up-regulated by NaCl treatment. These results suggest that NaCl-induced bioactive GA deficiency is caused by up-regulated expression of GA-inactivated genes, and the up-regulated expression of GA biosynthetic genes might be a consequence of negative feedback regulation of the bioactive GA deficiency. Moreover, we provide evidence that NaCl-induced bioactive GA deficiency inhibits rice seed germination by decreasing α-amylase activity via down-regulation of α-amylase gene expression. Additionally, exogenous bioactive GA rescues NaCl-inhibited seed germination by enhancing α-amylase activity. Thus, NaCl treatment reduces bioactive GA content through promotion of bioactive GA inactivation, which in turn inhibits rice seed germination by decreasing α-amylase activity via down-regulation of α-amylase gene expression.

  16. Two-line hybrid rice male sterile line 'NHR111S' with a marker of green-revertible albino leaves

    International Nuclear Information System (INIS)

    Wu Wei; Liu Xin; Shu Xiaoli; Shu Qingyao; Xia Yingwu; Wu Dianxing

    2006-01-01

    NHR111S is a new two-line male sterile line with a marker of green-revertible albino leave that was bred from in vitro mutagens is of the thermo/photoperiod-sensitive male sterile line 'Guangzhan63S' by 60 Co γ-rays. It has the same desired agronomic traits, fertility characteristics and combining ability as characteristics of the parent. It is convenient to develop leaf color marker-aided elimination strategy in the multiplication and production of hybrid rice seeds. (authors)

  17. Effect of 211At treating pollen and stigma on generative cells and seed setting of rice

    International Nuclear Information System (INIS)

    Jin Jiannan; Mo Shangwu; Liu Ning; Zhou Maolun; Zhang Shuyuan; Chen Fang; Zhang Yizheng; Gao Maoguo

    1998-01-01

    Low specific radioactivity (7.4 kBq/ml) 211 At treating pollen and stigma can obviously affect morphological structures and physiological functions of pollen, stigma and ovule or embryo sac cells, and cause injury. Results showed that because of the radiation effects the seed setting rate of rice was decreased, and the development of some embryos were affected and others became abnormal

  18. Rice grain yield as affected by subsoiling, compaction on sowing furrow and seed treatment

    Directory of Open Access Journals (Sweden)

    Veneraldo Pinheiro

    2016-05-01

    Full Text Available ABSTRACT This study aimed to determine the effects of subsoiling, compaction on sowing furrow and seed treatments with insecticides on the grain yield of upland rice cultivated under no-tillage. Two experiments were carried out, one in an area with and the other in an area without subsoiling, in which five seed treatments combined with five compaction pressures on the sowing furrow were compared in a randomized block design, in a factorial scheme, with three replicates. The seed treatments were: T0 - without treatment, T1 - imidacloprid + thiodicarb, T2 - thiamethoxam, T3 - carbofuran, and T4 - fipronil + pyraclostrobin + thiophanate methyl. The compaction pressures were: 25, 42, 126, 268 and 366 kPa. Subsoiling positively affected rice yield in the presence of higher compaction pressures on the sowing furrow. Seed treatment was effective at increasing rice grain yield only at the lowest compaction pressures. Rice yield showed quadratic response to compaction on the sowing furrow, with maximum values obtained at pressures ranging from 238.5 to 280.3 kPa.

  19. Salinity induced metabolic changes in rice (oryza sativa l.) seeds during germination

    International Nuclear Information System (INIS)

    Shereen, A.; Ansari, R.; Raza, A.; Mumtaz, S.; Khan, M.A.; Khan, M.A.

    2011-01-01

    Six inbred lines of rice exhibiting differential tolerance to salinity were exposed to 0, 50, 75, 100 and 200 mM NaCl for 24, 48, 72 and 96 h. The salinity induced metabolic changes (solute leakage, K efflux and a-amylase activity) were studied during germination. Germination of rice seeds was not affected by NaCl concentration less than 100 mM. At higher salinity levels (100 and 200 mM NaCl), a delay of 3-6 days in germination was observed. In the present study, comparatively higher values of solute leakage were observed in those lines in which germination was comparatively affected more adversely (sensitive). Sodium chloride reduced alpha-amylase activity in germinating rice seeds to varying degree even at low NaCl concentrations (50 and 75 mM), where germination was not affected greatly. The tolerant lines exhibited higher enzymatic activity than the sensitive ones. (author)

  20. Impact Of Different Time Planting In Soybeans And Neem Seed Extract Application To Insect Population On Rice Field

    Directory of Open Access Journals (Sweden)

    Tamrin Abdullah

    2015-08-01

    Full Text Available Abstract The purpose of research is to study impact of different time planting of soybean and neem seed extract application to pest insect population on rice field. The research was used Random Block Design in three treatment of insecticides application i.e neem seed extract together with rice planting neem seed extract on soybean 17 days after rice planting synthetic insecticides on 17 days after rice planting Delthametrin on soybean and Chlorpirifos on rice respectively. Research was conducted in rice fields with irrigation channels. The land area is 0.8 hectares with extensive experiments each rice terraces approximately 900 m2 with separate by rice terraces for every treatment. Each treatment consisted of three groups and using nine rice terraces. Samples of the rice plant population is 25 plants per sample unit. The results was showed treatment by neem seed extract with different time planting of soybeans able to reduce number of pest insects populations such as N. virescens 80.38 N. lugens 67.17 S. incertulas 66.5 and L. oratorius 93.46 when compared to treatment with synthetic insecticides Delthamethrin and Chlorpyrifos.

  1. Studies on combining ability and heritability of milling and physical properties in indica hybrid rice

    International Nuclear Information System (INIS)

    Zhang Lihua; Wang Linyou; Wang Jianjun

    2003-01-01

    14 different qualities parents of indica hybrid rice, including 7 CMS lines and 7 restorers, were chosen to analyze the combining ability of milling property and physical property by way of p x q incomplete diallel cross (NC II) design. The results showed that: 1) Both general combining ability (gca) and specific combining ability (sca) were highly significant in all 12 characters; the genetic additive effects was principal in brown rice length (BRL), brown rice width (BRW), ratio of length to width of brown rice (RLWBR), milled rice length (MRL), milled rice width (MRW), ratio of length to width of milled rice (RLWMR) and chalkyness (CN); while the nonadditive effects were greater in brown rice rate (BRR), milled rice rate (MRR), head rice rate (HRR), chalky rice percentage (CRP) and area of chalky rice (ACR). 2) Through the analysis of the contribution ratio of the male, female and their interaction to the total variance of the quality characters in F 1 hybrids, the results showed that BRR, MRR, BRL, MRL and ACR were influenced more greatly by restorer line than by CMS line, but the others were influenced more greatly by CMS line than by restorer line. 3) The gca and sca effects were independent each other, which suggests that it is essential to make widely testcrosses in the selection of hybrid combinations. There existed a positive correlation between gca and phenotypic value of parents, which indicates that great attention must be paid to the improvement of parent own characters in hybrid rice breeding. 4) BRL, BRW, RLWBR, MRL, MRW and RLWMR had higher narrow heritabilities (h N 2 ), and these characters may be used as indirect traits in early breeding generation

  2. Embryo-specific expression of soybean oleosin altered oil body morphogenesis and increased lipid content in transgenic rice seeds.

    Science.gov (United States)

    Liu, Wen Xian; Liu, Hua Liang; Qu, Le Qing

    2013-09-01

    Oleosin is the most abundant protein in the oil bodies of plant seeds, playing an important role in regulating oil body formation and lipid accumulation. To investigate whether lipid accumulation in transgenic rice seeds depends on the expression level of oleosin, we introduced two soybean oleosin genes encoding 24 kDa proteins into rice under the control of an embryo-specific rice promoter REG-2. Overexpression of soybean oleosin in transgenic rice leads to an increase of seed lipid content up to 36.93 and 46.06 % higher than that of the non-transgenic control, respectively, while the overall fatty acid profiles of triacylglycerols remained unchanged. The overexpression of soybean oleosin in transgenic rice seeds resulted in more numerous and smaller oil bodies compared with wild type, suggesting that an inverse relationship exists between oil body size and the total oleosin level. The increase in lipid content is accompanied by a reduction in the accumulation of total seed protein. Our results suggest that it is possible to increase rice seed oil content for food use and for use as a low-cost feedstock for biodiesel by overexpressing oleosin in rice seeds.

  3. Rice is the seed of the monocot plants Oryza sativa (Asian rice) or ...

    African Journals Online (AJOL)

    BIOTECH

    2013-10-16

    Oct 16, 2013 ... of culture. The regenerated plantlets were transferred to pots for acclimatization. About 80% of plants were survived in the greenhouse condition. Key words: Somatic embryogenesis, immature zygotic embryos, Indica rice, plant regeneration. INTRODUCTION. Rice (Oryza sativa L.) is one of the most ...

  4. Accumulation and distribution of elements in rice (seed, brand layer, husk) by neutron activation analysis

    International Nuclear Information System (INIS)

    Tran Van, L.; Teherani, D.K.

    1988-01-01

    Various rice samples (seed, brand layer, husk) from Vietnam were analyzed for Se, Hg, Cr, Ni, Sc, Rb, Fe, Zn and Co by neutron activation analysis. The concentration values found (seed) were as follows: Se 0.04-0.07 ppm, Hg 0.02-0.07 ppm, Cr 2.13-8.65 ppm, Ni 1.56-4.95 ppm, Sc 0.02-0.06 ppm, Rb 0.84-2.71 ppm, Fe 26.31-96.07 ppm, Zn 10.65-27.39 ppm and Co 0.02-0.15 ppm. The values were reported in ppm (dry weight). Statistical analysis showed that the content of elements varies in different parts of rice; the content of Rb, Fe, Ni, Cr of husk was significantly higher than in seed and brand layer. (author) 12 refs.; 2 figs.; 1 tab

  5. Asian wild rice is a hybrid swarm with extensive gene flow and feralization from domesticated rice

    OpenAIRE

    Wang, Hongru; Garrett Vieira, Filipe Jorge; Crawford, Jacob E.; Chu, Chengcai; Nielsen, Rasmus

    2017-01-01

    The domestication history of rice remains controversial, with multiple studies reaching different conclusions regarding its origin(s). These studies have generally assumed that populations of living wild rice, O. rufipogon, are descendants of the ancestral population that gave rise to domesticated rice, but relatively little attention has been paid to the origins and history of wild rice itself. Here, we investigate the genetic ancestry of wild rice by analyzing a diverse panel of rice genome...

  6. Copper suppresses abscisic acid catabolism and catalase activity, and inhibits seed germination of rice.

    Science.gov (United States)

    Ye, Nenghui; Li, Haoxuan; Zhu, Guohui; Liu, Yinggao; Liu, Rui; Xu, Weifeng; Jing, Yu; Peng, Xinxiang; Zhang, Jianhua

    2014-11-01

    Although copper (Cu) is an essential micronutrient for plants, a slight excess of Cu in soil can be harmful to plants. Unfortunately, Cu contamination is a growing problem all over the world due to human activities, and poses a soil stress to plant development. As one of the most important biological processes, seed germination is sensitive to Cu stress. However, little is known about the mechanism of Cu-induced inhibition of seed germination. In the present study, we investigated the relationship between Cu and ABA which is the predominant regulator of seed germination. Cu at a concentration of 30 µM effectively inhibited germination of rice caryopsis. ABA content in germinating seeds under copper stress was also higher than that under control conditions. Quantitative real-time PCR (qRT-PCR) revealed that Cu treatment reduced the expression of OsABA8ox2, a key gene of ABA catabolism in rice seeds. In addition, both malondialdehyde (MDA) and H2O2 contents were increased by Cu stress in the germinating seeds. Antioxidant enzyme assays revealed that only catalase activity was reduced by excess Cu, which was consistent with the mRNA profile of OsCATa during seed germination under Cu stress. Together, our results demonstrate that suppression of ABA catabolism and catalase (CAT) activity by excess Cu leads to the inhibition of seed germination of rice. © 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.

  7. Analysis the parameters of seed quality in ns sunflower hybrid after processing in gravity separator

    Directory of Open Access Journals (Sweden)

    Jokić Goran

    2016-01-01

    Full Text Available This paper analyzed the processed seed of five sunflower hybrid seed developed at the Institute of Field and Vegetable Crops in Novi Sad before and after processing in gravity separator. The cultivars were Pegaz, Duško, NS Fantazija, Sumo 1 PR and NS Oskar. The analysis was conducted on seed lots processed in 2015 and involved the following parameters: seed purity percentage, 1.000-seed weight, germination energy, germination, seed moisture, number of sclerotinia per 1.000. The results showed that all the parameters of seed quality of sunflower hybrids were better after processing seeds in the gravity separator.

  8. Effect of atmospheric plasma treatment on seed germination of rice (Oryza sativa L.)

    Science.gov (United States)

    Penado, Keith Nealson M.; Mahinay, Christian Lorenz S.; Culaba, Ivan B.

    2018-01-01

    Multiple methods of improving plant development have been utilized over the past decades. Despite these improvements, there still exists a need for better planting methods due to the increasing population of a global community. Studies have reported that plasma treatment affects the growth and germination of a variety of plant species, including a multitude of grains which often takes the bulk in the diet of the average human being. This study explores the effect of atmospheric air plasma jet treatment on the seed germination of rice (Oryza sativa L.). The seeds were treated using an atmospheric air plasma jet for 1, 2, and 3 s. The effect of plasma exposure shows a reduction of trichomes on the surface of the seed. This caused a possible increase in wettability which significantly affected the seed germ length but did not affect the seed germination count after the germination period of 72 h.

  9. Timing is everything: early degradation of abscission layer is associated with increased seed shattering in U.S. weedy rice

    Directory of Open Access Journals (Sweden)

    Hepler Peter K

    2011-01-01

    Full Text Available Abstract Background Seed shattering, or shedding, is an important fitness trait for wild and weedy grasses. U.S. weedy rice (Oryza sativa is a highly shattering weed, thought to have evolved from non-shattering cultivated ancestors. All U.S. weedy rice individuals examined to date contain a mutation in the sh4 locus associated with loss of shattering during rice domestication. Weedy individuals also share the shattering trait with wild rice, but not the ancestral shattering mutation at sh4; thus, how weedy rice reacquired the shattering phenotype is unknown. To establish the morphological basis of the parallel evolution of seed shattering in weedy rice and wild, we examined the abscission layer at the flower-pedicel junction in weedy individuals in comparison with wild and cultivated relatives. Results Consistent with previous work, shattering wild rice individuals possess clear, defined abscission layers at flowering, whereas non-shattering cultivated rice individuals do not. Shattering weedy rice from two separately evolved populations in the U.S. (SH and BHA show patterns of abscission layer formation and degradation distinct from wild rice. Prior to flowering, the abscission layer has formed in all weedy individuals and by flowering it is already degrading. In contrast, wild O. rufipogon abscission layers have been shown not to degrade until after flowering has occurred. Conclusions Seed shattering in weedy rice involves the formation and degradation of an abscission layer in the flower-pedicel junction, as in wild Oryza, but is a developmentally different process from shattering in wild rice. Weedy rice abscission layers appear to break down earlier than wild abscission layers. The timing of weedy abscission layer degradation suggests that unidentified regulatory genes may play a critical role in the reacquisition of shattering in weedy rice, and sheds light on the morphological basis of parallel evolution for shattering in weedy and wild

  10. Combined Mass Spectrometry-Based Metabolite Profiling of Different Pigmented Rice (Oryza sativa L. Seeds and Correlation with Antioxidant Activities

    Directory of Open Access Journals (Sweden)

    Ga Ryun Kim

    2014-09-01

    Full Text Available Nine varieties of pigmented rice (Oryza sativa L. seeds that were black, red, or white were used to perform metabolite profiling by using ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS and gas chromatography (GC TOF-MS, to measure antioxidant activities. Clear grouping patterns determined by the color of the rice seeds were identified in principle component analysis (PCA derived from UPLC-Q-TOF-MS. Cyanidin-3-glucoside, peonidin-3-glucoside, proanthocyanidin dimer, proanthocyanidin trimer, apigenin-6-C-glugosyl-8-C-arabiboside, tricin-O-rhamnoside-O-hexoside, and lipids were identified as significantly different secondary metabolites. In PCA score plots derived from GC-TOF-MS, Jakwangdo (JKD and Ilpoom (IP species were discriminated from the other rice seeds by PC1 and PC2. Valine, phenylalanine, adenosine, pyruvate, nicotinic acid, succinic acid, maleic acid, malonic acid, gluconic acid, xylose, fructose, glucose, maltose, and myo-inositol were significantly different primary metabolites in JKD species, while GABA, asparagine, xylitol, and sucrose were significantly distributed in IP species. Analysis of antioxidant activities revealed that black and red rice seeds had higher activity than white rice seeds. Cyanidin-3-glucoside, peonidin-3-glucoside, proanthocyanidin dimers, proanthocyanidin trimers, and catechin were highly correlated with antioxidant activities, and were more plentiful in black and red rice seeds. These results are expected to provide valuable information that could help improve and develop rice-breeding techniques.

  11. DNA demethylation activates genes in seed maternal integument development in rice (Oryza sativa L.).

    Science.gov (United States)

    Wang, Yifeng; Lin, Haiyan; Tong, Xiaohong; Hou, Yuxuan; Chang, Yuxiao; Zhang, Jian

    2017-11-01

    DNA methylation is an important epigenetic modification that regulates various plant developmental processes. Rice seed integument determines the seed size. However, the role of DNA methylation in its development remains largely unknown. Here, we report the first dynamic DNA methylomic profiling of rice maternal integument before and after pollination by using a whole-genome bisulfite deep sequencing approach. Analysis of DNA methylation patterns identified 4238 differentially methylated regions underpin 4112 differentially methylated genes, including GW2, DEP1, RGB1 and numerous other regulators participated in maternal integument development. Bisulfite sanger sequencing and qRT-PCR of six differentially methylated genes revealed extensive occurrence of DNA hypomethylation triggered by double fertilization at IAP compared with IBP, suggesting that DNA demethylation might be a key mechanism to activate numerous maternal controlling genes. These results presented here not only greatly expanded the rice methylome dataset, but also shed novel insight into the regulatory roles of DNA methylation in rice seed maternal integument development. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  12. Waste rice seed in conventional and stripper-head harvested fields in California: Implications for wintering waterfowl

    Science.gov (United States)

    Fleskes, Joseph P.; Halstead, Brian J.; Casazza, Michael L.; Coates, Peter S.; Kohl, Jeffrey D.; Skalos, Daniel A.

    2012-01-01

    Waste rice seed is an important food for wintering waterfowl and current estimates of its availability are needed to determine the carrying capacity of rice fields and guide habitat conservation. We used a line-intercept method to estimate mass-density of rice seed remaining after harvest during 2010 in the Sacramento Valley (SACV) of California and compared results with estimates from previous studies in the SACV and Mississippi Alluvial Valley (MAV). Posterior mean (95% credible interval) estimates of total waste rice seed mass-density for the SACV in 2010 were 388 (336–449) kg/ha in conventionally harvested fields and 245 (198–307) kg/ha in stripper-head harvested fields; the 2010 mass-density is nearly identical to the mid-1980s estimate for conventionally harvested fields but 36% lower than the mid-1990s estimate for stripped fields. About 18% of SACV fields were stripper-head harvested in 2010 vs. 9–15% in the mid-1990s and 0% in the mid-1980s; but due to a 50% increase in planted rice area, total mass of waste rice seed in SACV remaining after harvest in 2010 was 43% greater than in the mid-1980s. However, total mass of seed-eating waterfowl also increased 82%, and the ratio of waste rice seed to seed-eating waterfowl mass was 21% smaller in 2010 than in the mid-1980s. Mass-densities of waste rice remaining after harvest in SACV fields are within the range reported for MAV fields. However, because there is a lag between harvest and waterfowl use in the MAV but not in the SACV, seed loss is greater in the MAV and estimated waste seed mass-density available to wintering waterfowl in SACV fields is about 5–30 times recent MAV estimates. Waste rice seed remains an abundant food source for waterfowl wintering in the SACV, but increased use of stripper-head harvesters would reduce this food. To provide accurate data on carrying capacities of rice fields necessary for conservation planning, trends in planted rice area, harvest method, and postharvest field

  13. Genome-wide association study of salt tolerance at the seed germination stage in rice.

    Science.gov (United States)

    Shi, Yingyao; Gao, Lingling; Wu, Zhichao; Zhang, Xiaojing; Wang, Mingming; Zhang, Congshun; Zhang, Fan; Zhou, Yongli; Li, Zhikang

    2017-05-30

    Improving the salt tolerance of direct-seeding rice at the seed germination stage is a major breeding goal in many Asian rice-growing countries, where seedlings must often establish in soils with a high salt content. Thus, it is important to understand the genetic mechanisms of salt tolerance in rice and to screen for germplasm with salt tolerance at the seed germination stage. Here, we investigated seven seed germination-related traits under control and salt-stress conditions and conducted a genome-wide association study based on the re-sequencing of 478 diverse rice accessions. The analysis used a mixed linear model and was based on 6,361,920 single nucleotide polymorphisms in 478 rice accessions grouped into whole, indica, and non-indica panels. Eleven loci containing 22 significant salt tolerance-associated single nucleotide polymorphisms were identified based on the stress-susceptibility indices (SSIs) of vigor index (VI) and mean germination time (MGT). From the SSI of VI, six major loci were identified, explaining 20.2% of the phenotypic variation. From the SSI of MGT, five major loci were detected, explaining 26.4% of the phenotypic variation. Of these, seven loci on chromosomes 1, 5, 6, 11, and 12 were close to six previously identified quantitative gene loci/genes related to tolerance to salinity or other abiotic stresses. The strongest association region for the SSI of MGT was identified in a ~ 13.3 kb interval (15450039-15,463,330) on chromosome 1, near salt-tolerance quantitative trait loci controlling the Na + : K + ratio, total Na + uptake, and total K + concentration. The strongest association region for the SSI of VI was detected in a ~ 164.2 kb interval (526662-690,854) on chromosome 2 harboring two nitrate transporter family genes (OsNRT2.1 and OsNRT2.2), which affect gene expression under salt stress. The haplotype analysis indicated that OsNRT2.2 was associated with subpopulation differentiation and its minor/rare tolerant haplotype was

  14. Phenology, sterility and inheritance of two environment genic male sterile (EGMS) lines for hybrid rice.

    Science.gov (United States)

    El-Namaky, R; van Oort, P A J

    2017-12-01

    There is still limited quantitative understanding of how environmental factors affect sterility of Environment-conditioned genic male sterility (EGMS) lines. A model was developed for this purpose and tested based on experimental data from Ndiaye (Senegal) in 2013-2015. For the two EGMS lines tested here, it was not clear if one or more recessive gene(s) were causing male sterility. This was tested by studying sterility segregation of the F2 populations. Daylength (photoperiod) and minimum temperatures during the period from panicle initiation to flowering had significant effects on male sterility. Results clearly showed that only one recessive gene was involved in causing male sterility. The model was applied to determine the set of sowing dates of two different EGMS lines such that both would flower at the same time the pollen would be completely sterile. In the same time the local popular variety (Sahel 108, the male pollen donor) being sufficiently fertile to produce the hybrid seeds. The model was applied to investigate the viability of the two line breeding system in the same location with climate change (+2oC) and in two other potential locations: in M'Be in Ivory Coast and in the Nile delta in Egypt. Apart from giving new insights in the relation between environment and EGMS, this study shows that these insights can be used to assess safe sowing windows and assess the suitability of sterility and fertility period of different environments for a two line hybrid rice production system.

  15. Weed control in organic rice using plastic mulch and water seeding methods in addition to cover crops

    Science.gov (United States)

    Weeds are a major yield limiting factor in organic rice farming and are more problematic than in conventional production systems. Water seeding is a common method of reducing weed pressure in rice fields as many weeds connot tolerate flooded field conditions. The use of cover crops is another method...

  16. PERFORMANCE OF PROMISING HYBRID RICE IN TWO DIFFERENT ELEVATIONS OF IRRIGATED LOWLAND IN INDONESIA

    Directory of Open Access Journals (Sweden)

    Yuni Widyastuti

    2015-06-01

    Full Text Available The hybrid rice program has been established since early 1990’s at the Indonesia Center for Rice Research (ICRR. Twenty-four experimental hybrid rice varieties which have been developed were tested in lowland rice fields in Sukamandi (West Java and Batang (Central Java during the dry season and the rainy season of 2012. Randomized complete block design (RCBD with three replications was used in each location. The results showed that grains yields were affected by locations, seasons, and genotypes. The genotypes x locations x seasons interaction effect was significant; therefore, the best hybrid was different for each location and season. A7/PK36 hybrid has the best performance in Batang during the dry season, while A7/PK40 and A7/PK32 are the best hybrids in the rainy season. In Sukamandi, nine hybrids were identified as better yielder than that of the check cultivar in the dry season, but not so in the rainy season. Using the correlation and path analysis, we found that the number of panicles per hill and the number of filled grains per panicle could be used as selection criteria for yield in hybrid rice.

  17. Workable male sterility systems for hybrid rice: Genetics, biochemistry, molecular biology, and utilization.

    Science.gov (United States)

    Huang, Jian-Zhong; E, Zhi-Guo; Zhang, Hua-Li; Shu, Qing-Yao

    2014-12-01

    The exploitation of male sterility systems has enabled the commercialization of heterosis in rice, with greatly increased yield and total production of this major staple food crop. Hybrid rice, which was adopted in the 1970s, now covers nearly 13.6 million hectares each year in China alone. Various types of cytoplasmic male sterility (CMS) and environment-conditioned genic male sterility (EGMS) systems have been applied in hybrid rice production. In this paper, recent advances in genetics, biochemistry, and molecular biology are reviewed with an emphasis on major male sterility systems in rice: five CMS systems, i.e., BT-, HL-, WA-, LD- and CW- CMS, and two EGMS systems, i.e., photoperiod- and temperature-sensitive genic male sterility (P/TGMS). The interaction of chimeric mitochondrial genes with nuclear genes causes CMS, which may be restored by restorer of fertility (Rf) genes. The PGMS, on the other hand, is conditioned by a non-coding RNA gene. A survey of the various CMS and EGMS lines used in hybrid rice production over the past three decades shows that the two-line system utilizing EGMS lines is playing a steadily larger role and TGMS lines predominate the current two-line system for hybrid rice production. The findings and experience gained during development and application of, and research on male sterility in rice not only advanced our understanding but also shed light on applications to other crops.

  18. Foliar application of molybdenum reduces yield loss and pre-harvest sprouting in japonica rice seed subjected to simulated flooding during seed development and maturation

    OpenAIRE

    Tejakhod, Sujittra; Hammond, John P.; Ellis, Richard H.

    2018-01-01

    Flooding damages rice crops and its incidence is increasing. Foliar spray applications of molybdenum (100, 600 or 3000 mg Mo L-1), abscisic acid (ABA, 50 μM), or deionised water (control) were made to pot-grown plants of the Japonica rice cv. Gleva at flag leaf appearance to determine their effects on seed yield and pre-harvest sprouting after flooding. Plants were submerged , to simulate flooding, for four days from 20 or 30 days after anthesis (DAA). Seed yield per plant, seed weight, and p...

  19. 7 CFR 457.112 - Hybrid sorghum seed crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... test. A warm germination test performed on clean seed according to specifications of the “Rules for.... Germination of less than 80 percent of the commercial hybrid sorghum seed as determined by using a certified seed test. Insurable interest. Your share of the financial loss that occurs in the event seed...

  20. Sustained expression of human cytomegalovirus glycoprotein B (UL55) in the seeds of homozygous rice plants.

    Science.gov (United States)

    Tackaberry, Eilleen S; Prior, Fiona A; Rowlandson, Karen; Tocchi, Monika; Mehic, Jelica; Porter, Suzanne; Walsh, Mike; Schleiss, Mark R; Ganz, Peter R; Sardana, Ravinder K; Altosaar, Illimar; Dudani, Anil K

    2008-09-01

    Production of recombinant subunit vaccines in transgenic plants may be a means of reducing vaccine costs while increasing availability and safety. A plant-derived product found safe and effective for oral administration would provide additional advantages when used as a vaccine. Outstanding issues with the technology include transgene stability through successive generations and consistent bioproduction. We previously reported expression of glycoprotein B (gB) of human cytomegalovirus in seeds of transgenic tobacco. Here the goal was to determine if gB could be similarly expressed in rice, and if so, to examine expression over several plant generations. Results show that immunoreactive gB was successfully expressed in transgenic rice seeds, with sustained expression over three generations. The gB contained several neutralizing epitopes and was stable over 27 months.

  1. Effects of gamma-rays and neutrons on the seedling and callus growth in rice seeds

    International Nuclear Information System (INIS)

    Baradjanegara, A.A.; Fujii, Taro; Amano, Etsuo

    1976-01-01

    Seeds of rice c.v. Norin-8 and two radiation induced dwarf mutants MGS-46 and -96 were used to investigate the effects of gamma- and 14 MeV neutron-radiations in different culture systems. Seedling growth of irradiated seeds in soil, and in two types of synthetic media, modified White's (M-W) or modified Eriksson's (M-E), as well as the callus growth on 2.4-D supplemented media were measured as an index of radiation damage. Comparing the seedling height about two types of media, the M-E promoted the plant growth than the M-W in irradiated as well as non-irradiated lots of the three strains studied. The callus growth on M-E surpassed by more 10 times that obrained on the M-W in all the lots. The M-E medium seem to be appropriate for both the seedling and callus growth of rice. (auth.)

  2. Enhancement in seed germinability of rice (oryza sativa L.) by pre-sowing seed treatment with nitric oxide (NO) under salt stress

    International Nuclear Information System (INIS)

    Habib, N.; Ashraf, M.; Ahmad, M.S.

    2010-01-01

    The seeds of two fine-rice (Shaheen and PB-95) and two coarse rice (IRRI-6 and KS-282) cultivars were soaked in varying levels of nitric oxide (NO) (0, 0.05, 0.1, 0.2, 0.3, 0.4 and 0.5 mM) and then exposed to 80 mM NaCl in sand culture. Application of salt stress significantly reduced seed germinability parameters of all four rice cultivars in terms of percent seed germinated, germination index and seedling fresh and dry weights. The toxic effects of salt stress in reducing seed germinability were greater in fine rice cultivars (Shaheen and PB-95) as compared to those in coarse ones (IRRI-6 and KS-282). Although, the application of lower levels of nitric oxide (0.05, 0.1 and 0.2 mM) as pre-sowing seed treatment showed a significant improvement, 0.1 and 0.2 mM NO were found to be the most effective in improving seed germinability under salt stress. With a further increase in NO concentration (0.3 mM) as pre-sowing seed treatment, the seed germinability parameters differed non-significantly from those of control plants, while the highest levels (0.4 and 0.5 mM) showed significant inhibitory effects on seed germination and early seedling growth. It was concluded that lower levels of NO (0.1 and 0.2 mM) could be used to effectively enhance seed germination of rice plants under salt stress. (author)

  3. Method of phorbol ester degradation in Jatropha curcas L. seed cake using rice bran lipase.

    Science.gov (United States)

    Hidayat, Chusnul; Hastuti, Pudji; Wardhani, Avita Kusuma; Nadia, Lana Santika

    2014-03-01

    A novel enzymatic degradation of phorbol esters (PE) in the jatropha seed cake was developed using lipase. Cihera rice bran lipase had the highest ability to hydrolyze PE, and reduced PE to a safe level after 8 h of incubation. Enzymatic degradation may be a promising method for PE degradation. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  4. Investigation of Genetic Distance among Parental Lines of Hybrid Rice Based on Cluster Analysis of Morphological Traits

    Directory of Open Access Journals (Sweden)

    A. Baluch-Zehi

    2013-06-01

    Full Text Available conditions. Thus, these varieties could be suitable option for yield increase and an effective step toward food security. Selection of parental lines has essential role in developing ideal combinations. Therefore, it is essential to study the relationship and genetic diversity among parental lines in hybrid rice. Sixteen hybrid rice parental lines including 6 restorer lines (Poya, Sepidrud, Pajohesh, R2, R9 and IR50 and 5 CMS lines (Neda, Nemat, Dasht, Champa and Amol 3 with their 5 maintainers were studied at Research Farm of Sari Agricultural Sciences and Natural Resources University during 2011. Analysis of variance showed significant variations for all of the studied traits, which shows great diversity among the genotypes. The number of fertile tillers and length to width ratio of grain showed positive and significant correlation with yield. But, grain width showed negative and significant correlation with yield. Results of principal component analysis revealed that 3 components explained 75.64% of the total variations. Cluster analysis at 15 genetic distance criteria grouped genotypes in 4 clusters. In exploration of heterosis phenomenon, parents must be far away from each other. So, the results of this study suggested crosses between CMS lines of Neda A, Nemat A and Champa A with each of restorer lines R9, R2, IR50 and Poya for experimental hybrid seed production.

  5. Effects of Cadmium Stress on Seed Germination, Seedling Growth and Seed Amylase Activities in Rice (Oryza sativa

    Directory of Open Access Journals (Sweden)

    Jun-yu HE

    2008-12-01

    Full Text Available Two rice varieties, Xiushui 110 with high cadmium (Cd tolerance and Xiushui 11 with low Cd tolerance were used to study the effects of Cd stress on seed germination, seedling growth and amylase activities. The low cadmium concentration had little effect on seed germination rate. However, cadmium stress could significantly inhibit plumule and radicle growth, especially for radicle growth. Germination index, vigour index, radicle length and amylase activities of Xiushui 11 decreased more significantly with the increasing cadmium level compared with Xiushui 110. The cadmium content in seedlings of Xiushui 11 was higher than that in Xiushui 110 when the cadmium concentration exceeded 5 μmol/L, which caused lower mitotic index in root tips and amylase activities, and more serious cadmium toxicity in Xiushui 11.

  6. Physiological characteristics and related gene expression of after-ripening on seed dormancy release in rice.

    Science.gov (United States)

    Du, W; Cheng, J; Cheng, Y; Wang, L; He, Y; Wang, Z; Zhang, H

    2015-11-01

    After-ripening is a common method used for dormancy release in rice. In this study, the rice variety Jiucaiqing (Oryza sativa L. subsp. japonica) was used to determine dormancy release following different after-ripening times (1, 2 and 3 months). Germination speed, germination percentage and seedling emergence increased with after-ripening; more than 95% germination and 85% seedling emergence were observed following 1 month of after-ripening within 10 days of imbibition, compared with rice dormancy release. Dormancy release by after-ripening is mainly correlated with a rapid decline in ABA content and increase in IAA content during imbibition. Subsequently, GA(1)/ABA, GA(7)/ABA, GA(12)/ABA, GA(20)/ABA and IAA/ABA ratios significantly increased, while GA(3)/ABA, GA(4)/ABA and GAs/IAA ratio significantly decreased in imbibed seeds following 3 months of after-ripening, thereby altering α-amylase activity during seed germination. Peak α-amylase activity occurred at an earlier germination stage in after-ripened seeds than in freshly harvested seeds. Expression of ABA, GA and IAA metabolism genes and dormancy-related genes was regulated by after-ripening time upon imbibition. Expression of OsCYP707A5, OsGA2ox1, OsGA2ox2, OsGA2ox3, OsILR1, OsGH3-2, qLTG3-1 and OsVP1 increased, while expression of Sdr4 decreased in imbibed seeds following 3 months of after-ripening. Dormancy release through after-ripening might be involved in weakening tissues covering the embryo via qLTG3-1 and decreased ABA signalling and sensitivity via Sdr4 and OsVP1. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  7. Transgenic rice seed expressing flavonoid biosynthetic genes accumulate glycosylated and/or acylated flavonoids in protein bodies

    Science.gov (United States)

    Ogo, Yuko; Mori, Tetsuya; Nakabayashi, Ryo; Saito, Kazuki; Takaiwa, Fumio

    2016-01-01

    Plant-specialized (or secondary) metabolites represent an important source of high-value chemicals. In order to generate a new production platform for these metabolites, an attempt was made to produce flavonoids in rice seeds. Metabolome analysis of these transgenic rice seeds using liquid chromatography-photodiode array-quadrupole time-of-flight mass spectrometry was performed. A total of 4392 peaks were detected in both transgenic and non-transgenic rice, 20–40% of which were only detected in transgenic rice. Among these, 82 flavonoids, including 37 flavonols, 11 isoflavones, and 34 flavones, were chemically assigned. Most of the flavonols and isoflavones were O-glycosylated, while many flavones were O-glycosylated and/or C-glycosylated. Several flavonoids were acylated with malonyl, feruloyl, acetyl, and coumaroyl groups. These glycosylated/acylated flavonoids are thought to have been biosynthesized by endogenous rice enzymes using newly synthesized flavonoids whose biosynthesis was catalysed by exogenous enzymes. The subcellular localization of the flavonoids differed depending on the class of aglycone and the glycosylation/acylation pattern. Therefore, flavonoids with the intended aglycones were efficiently produced in rice seeds via the exogenous enzymes introduced, while the flavonoids were variously glycosylated/acylated by endogenous enzymes. The results suggest that rice seeds are useful not only as a production platform for plant-specialized metabolites such as flavonoids but also as a tool for expanding the diversity of flavonoid structures, providing novel, physiologically active substances. PMID:26438413

  8. Histones and their phosphorylation during germination of rice seeds

    International Nuclear Information System (INIS)

    Iqbal Ahmed, C.M.; Padayatti, J.D.

    1980-01-01

    Histones from nuclei of rice embryos were identified by their mobilities on 15% acid-urea polyacrylamide gel electrophoreogram, incorporation of ( 3 H)lysine and ( 14 C) arginine and lack of incorporation of ( 3 H)tryptophan. The ratio of histone to DNA in ungerminated embryos was 2.7 which decreased during germination reaching unity by 48 hr. There was preferential phosphorylation of lysine-rich histones, which paralleled the synthesis of DNA. In the presence of cytosine arabinoside and mitomycin-C, which inhibited the synthesis of DNA to the extend of 75-80% the phosphorylation of lysine-rich histone was reduced by 50-60% suggesting the dependence of phosphorylation on the ongoing synthesis of DNA. (auth.)

  9. Reactive Oxygen Species Generated by NADPH Oxidases Promote Radicle Protrusion and Root Elongation during Rice Seed Germination

    Directory of Open Access Journals (Sweden)

    Wen-Yan Li

    2017-01-01

    Full Text Available Seed germination is a complicated biological process that requires regulation through various enzymatic and non-enzymatic mechanisms. Although it has been recognized that reactive oxygen species (ROS regulate radicle emergence and root elongation in a non-enzymatic manner during dicot seed germination, the role of ROS in monocot seed germination remains unknown. NADPH oxidases (NOXs are the major ROS producers in plants; however, whether and how NOXs regulate rice seed germination through ROS generation remains unclear. Here, we report that diphenyleneiodinium (DPI, a specific NOX inhibitor, potently inhibited embryo and seedling growth—especially that of the radicle and of root elongation—in a dose-dependent manner. Notably, the DPI-mediated inhibition of radicle and root growth could be eliminated by transferring seedlings from DPI to water. Furthermore, ROS production/accumulation during rice seed germination was quantified via histochemistry. Superoxide radicals (O2−, hydrogen peroxide (H2O2 and hydroxyl radicals (•OH accumulated steadily in the coleorhiza, radicle and seedling root of germinating rice seeds. Expression profiles of the nine typical NOX genes were also investigated. According to quantitative PCR, OsNOX5, 7 and 9 were expressed relatively higher. When seeds were incubated in water, OsNOX5 expression progressively increased in the embryo from 12 to 48 h, whereas OsNOX7 and 9 expressions increased from 12 to 24 h and decreased thereafter. As expected, DPI inhibits the expression at predetermined time points for each of these genes. Taken together, these results suggest that ROS produced by NOXs are involved in radicle and root elongation during rice seed germination, and OsNOX5, 7 and 9 could play crucial roles in rice seed germination. These findings will facilitate further studies of the roles of ROS generated by NOXs during seed germination and seedling establishment and also provide valuable information for the

  10. Comparative Mapping of Seed Dormancy Loci Between Tropical and Temperate Ecotypes of Weedy Rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Lihua Zhang

    2017-08-01

    Full Text Available Genotypic variation at multiple loci for seed dormancy (SD contributes to plant adaptation to diverse ecosystems. Weedy rice (Oryza sativa was used as a model to address the similarity of SD genes between distinct ecotypes. A total of 12 quantitative trait loci (QTL for SD were identified in one primary and two advanced backcross (BC populations derived from a temperate ecotype of weedy rice (34.3°N Lat.. Nine (75% of the 12 loci were mapped to the same positions as those identified from a tropical ecotype of weedy rice (7.1°N Lat.. The high similarity suggested that the majority of SD genes were conserved during the ecotype differentiation. These common loci are largely those collocated/linked with the awn, hull color, pericarp color, or plant height loci. Phenotypic correlations observed in the populations support the notion that indirect selections for the wild-type morphological characteristics, together with direct selections for germination time, were major factors influencing allelic distributions of SD genes across ecotypes. Indirect selections for crop-mimic traits (e.g., plant height and flowering time could also alter allelic frequencies for some SD genes in agroecosystems. In addition, 3 of the 12 loci were collocated with segregation distortion loci, indicating that some gametophyte development genes could also influence the genetic equilibria of SD loci in hybrid populations. The SD genes with a major effect on germination across ecotypes could be used as silencing targets to develop transgene mitigation (TM strategies to reduce the risk of gene flow from genetically modified crops into weed/wild relatives.

  11. On the role of abscisic acid in seed dormancy of red rice.

    Science.gov (United States)

    Gianinetti, Alberto; Vernieri, Paolo

    2007-01-01

    Abscisic acid (ABA) is commonly assumed to be the primary effector of seed dormancy, but conclusive evidence for this role is lacking. This paper reports on the relationships occurring in red rice between ABA and seed dormancy. Content of free ABA in dry and imbibed caryopses, both dormant and after-ripened, the effects of inhibitors, and the ability of applied ABA to revert dormancy breakage were considered. The results indicate: (i) no direct correlation of ABA content with the dormancy status of the seed, either dry or imbibed; (ii) different sensitivity to ABA of non-dormant seed and seed that was forced to germinate by fluridone; and (iii) an inability of exogenous ABA to reinstate dormancy in fluridone-treated seed, even though applied at a pH which favoured high ABA accumulation. These considerations suggest that ABA is involved in regulating the first steps of germination, but unidentified developmental effectors that are specific to dormancy appear to stimulate ABA synthesis and to enforce the responsiveness to this phytohormone. These primary effectors appear physiologically to modulate dormancy and via ABA they effect the growth of the embryo. Therefore, it is suggested that ABA plays a key role in integrating the dormancy-specific developmental signals with the control of growth.

  12. The perspective effects of various seed coating substances on rice seed variety Khao Dawk Mali 105 storability II: the case study of chemical and biochemical properties.

    Science.gov (United States)

    Thobunluepop, P; Pan-in, W; Pawelzik, E; Vearasilp, S

    2009-04-01

    The aim of this study was to investigate the effects of seed coating substances; chemical fungicide (CA) and biological fungicide polymers [chitosan-lignosulphonate polymer (CL) and eugenol incorporated into chitosan-lignosulphonate polymer (E+CL)] on chemical and biochemical changes of rice seeds cv. KDML 105, which have been studied during storage for 12 months. CA significantly affected the rice seed chemical properties and the associated seed deterioration. After 12 months storage, protein content decreased accompanied by declined of lipid content, increased free fatty acids and activated lipoxygenase enzyme. In the case of biological fungicide coated seeds, the antioxidative scavenging enzymes were ascorbate peroxidase and superoxide dismutase and a high antioxidant activity protected them. Moreover, the sugar content was positive correlated with seed germination and vigor. The biological coated seeds were found to maintain high sugar contents inside the seeds, which resulted high seed storability significantly. In contrast, under fungicide stress (CA), those compounds were lost that directly affected seed vigor during storage.

  13. [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

  14. Indirect Effects of Field Management on Pollination Service and Seed Set in Hybrid Onion Seed Production.

    Science.gov (United States)

    Gillespie, Sandra; Long, Rachael; Williams, Neal

    2015-12-01

    Pollination in crops, as in native ecosystems, is a stepwise process that can be disrupted at any stage. Healthy pollinator populations are critical for adequate visitation, but pollination still might fail if crop management interferes with the attraction and retention of pollinators. Farmers must balance the direct benefits of applying insecticide and managing irrigation rates against their potential to indirectly interfere with the pollination process. We investigated these issues in hybrid onion seed production, where previous research has shown that high insecticide use reduces pollinator attraction. We conducted field surveys of soil moisture, nectar production, pollinator visitation, pollen-stigma interactions, and seed set at multiple commercial fields across 2 yr. We then examined how management actions, such as irrigation rate (approximated by soil moisture), or insecticide use could affect the pollination process. Onions produced maximum nectar at intermediate soil moisture, and high nectar production attracted more pollinators. Insecticide use weakly affected pollinator visitation, but when applied close to bloom reduced pollen germination and pollen tube growth. Ultimately, neither soil moisture nor insecticide use directly affected seed set, but the high correlation between pollinator visitation and seed set suggests that crop management will ultimately affect yields via indirect effects on the pollination process. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Management of rice seed during insurgency : a case study in Sierra Leone

    NARCIS (Netherlands)

    Mokuwa, G.A.

    2015-01-01

    Keywords: Technography, Oryza glaberrima, Oryza sativa, farmer hybrids, sub-optimal agriculture, farmer adaptive management, plant genetic resources, peace and extreme (wartime) conditions, local seed channels, selection for robustness, Sierra Leone, West Africa.

  16. Genomic DNA sequence and cytosine methylation changes of adult rice leaves after seeds space flight

    Science.gov (United States)

    Shi, Jinming

    In this study, cytosine methylation on CCGG site and genomic DNA sequence changes of adult leaves of rice after seeds space flight were detected by methylation-sensitive amplification polymorphism (MSAP) and Amplified fragment length polymorphism (AFLP) technique respectively. Rice seeds were planted in the trial field after 4 days space flight on the shenzhou-6 Spaceship of China. Adult leaves of space-treated rice including 8 plants chosen randomly and 2 plants with phenotypic mutation were used for AFLP and MSAP analysis. Polymorphism of both DNA sequence and cytosine methylation were detected. For MSAP analysis, the average polymorphic frequency of the on-ground controls, space-treated plants and mutants are 1.3%, 3.1% and 11% respectively. For AFLP analysis, the average polymorphic frequencies are 1.4%, 2.9%and 8%respectively. Total 27 and 22 polymorphic fragments were cloned sequenced from MSAP and AFLP analysis respectively. Nine of the 27 fragments from MSAP analysis show homology to coding sequence. For the 22 polymorphic fragments from AFLP analysis, no one shows homology to mRNA sequence and eight fragments show homology to repeat region or retrotransposon sequence. These results suggest that although both genomic DNA sequence and cytosine methylation status can be effected by space flight, the genomic region homology to the fragments from genome DNA and cytosine methylation analysis were different.

  17. [Impact of low temperature in young ear formation stage on rice seed setting.

    Science.gov (United States)

    Ma, Shu Qing; Liu, Xiao Hang; Deng, Kui Cai; Quan, Hu Jie; Tong, Li Yuan; Xi, Zhu Xiang; Chai, Qing Rong; Yang, Jun

    2018-01-01

    A low temperature treatment in rice booting key period was executed on the north slope of Changbai Mountains to construct the impact model of low temperature on rice shell rate, and to reveal the effects of low temperature at different stages of rice young panicle on seed setting. The results showed that effects of low temperature in the young ear formation stage on rice shell rate generally followed the logarithmic function, the lower the temperature was, the greater the temperature influence coefficient was, and the longer the low temperature duration was, the higher rice shell rate was. The seed setting rate was most sensitive to low temperature in the middle time of booting stage (the period from formation to meiosis of the pollen mother cell), followed by the early and later stages. During the booting stage, with 1 ℃ decrease of daily temperature under 2-, 3- and 5-day low temperature treatments, the shell rate increased by 0.5, 1.7 and 4.3 percentage, respectively, and with 1 ℃ decrease of daily minimum temperature, the shell rate increased by 0.4,1.8 and 4.5 percentage, respectively. The impact of 2-day low temperature was smaller than that of 3 days or more. The impact of accumulative cold-temperature on the shell rate followed exponential function. In the range of harmful low temperature, rice shell rate increased about 8.5 percentage with the accumulative cold-temperature increasing 10 ℃·d. When the 3 days average temperature dropped to 21.6, 18.0 and 15.0 ℃, or the 5 days average temperature dropped to 22.0, 20.4 and 18.5 ℃, or the accumulative cold-temperature was more than 8, 19, 26 ℃·d, the light, moderate and severe booting stage chilling injury would occur, respectively. In Northeast China, low temperature within 2 d in rice booting stage might not cause moderate and severe chilling injury.

  18. Development and appraisal of economical and sustainable approach for weed management in drill seeded aerobic rice (oryza sativa l.)

    International Nuclear Information System (INIS)

    Saqib, M.; Akbar, N.; Ehsanullah, A.; Ghafoor, A.

    2012-01-01

    Conventional rice cultivation by puddling and transplanting is a labor intensive activity. Water scarcity is a threat for the sustain ability of transplanted rice. In many areas of Asia, rice transplantation of rice is being replaced by direct seeding as farmers tried to solve the problems of labor cost and water scarcity but weed control is one of the major constraints to direct seeding. So, to control weeds in direct seeded rice present studies were designed. A two years study was conducted to develop sustainable and economical methods for managing weeds in aerobic rice grown by dry direct-seeding at Student's Farm, Department of Agronomy, University of Agriculture, Faisalabad during the years 2008 and 2009. Experiment was laid out in RCBD with five weed management strategies: hand weeding, hoeing with kasula, inter-row cultivation with tine cultivator, inter-row cultivation with spike hoe and chemical control with Nominee 100 SC along with control (no weeding). Weed dry weight was 300 g m/sup -2/, 257 g m/sup -2/, 225 g m/sup -2/ and 157 g m/sup -2/ less in hand weeding, hoeing, tine cultivator and Nominee 100 SC respectively than no weeding. Paddy yield was 221%, 203%, 181% and 105% more in hand weeding, hoeing, tine cultivator and Nominee 100 SC respectively than no weeding. (author)

  19. The perspective effects of various seed coating substances on rice seed variety Khao DAWK Mali 105 storability I: the case study of physiological properties.

    Science.gov (United States)

    Thobunluepop, P; Pawelzik, E; Vearasilp, S

    2008-10-01

    This study aimed to evaluate the perspective changes of several physiological performances of rice seeds cv. KDML 105 which were coated with various seed coating substances [chemical fungicide, captan (CA) and biological coating polymers; chitosan-lignosulphonate polymer (CL) and eugenol incorporated into chitosan-lignosulphonate polymer (E + CL)] during storage (12 months). CA significantly increased seed moisture content and seed water activity through out the storage period. The qualities and viability of the seeds were seriously declined by this treatment. Moreover, CA inhibited the shoot and root development, seedling dry weight accumulation, delayed the seed germination and seedling growth rate. CA treated seeds were susceptible to stress conditions that declined the seed germination potential under cold, high moisture and temperature stress conditions. Nevertheless, CL and E + CL coating polymer could maintain seed storability, which significantly improved seed germination and seedling performances. These improvements were attributed to maintain the nutritive reserve and dehydrogenase activity in seeds. Moreover, the biological seed treatment stimulated the embryo growth and so speeding up the seedling emergence when compared untreated seeds.

  20. Detection of DNA fingerprints of cultivated rice by hybridization with a human minisatellite DNA probe

    International Nuclear Information System (INIS)

    Dallas, J.F.

    1988-01-01

    A human minisatellite DNA probe detects several restriction fragment length polymorphisms in cultivars of Asian and African rice. Certain fragments appear to be inherited in a Mendelian fashion and may represent unlinked loci. The hybridization patterns appear to be cultivar-specific and largely unchanged after the regeneration of plants from tissue culture. The results suggest that these regions of the rice genome may be used to generate cultivar-specific DNA fingerprints. The demonstration of similarity between a human minisatellite sequence and polymorphic regions in the rice genome suggests that such regions also occur in the genomes of many other plant species

  1. Improvement of seed protein in rice through mutation breeding

    International Nuclear Information System (INIS)

    Monyo, J.H.; Sugiyama, T.

    1978-01-01

    Mutants selected from an M 4 generation on the basis of high yield potential and high grain protein content were grown in a preliminary yield trial. The two parent varieties, Faya Theresa and Kihogo Red, were grown as controls. Thirteen mutants originating from Faya Theresa and three mutants derived from Kihogo Red were found to be equal or superior in yield to the controls. The best improvement in protein content through mutagen treatment was 44% increase in a Faya Theresa mutant and 35% increase in a Kihogo Red mutant. The protein values obtained for the same mutants in the M 3 , M 4 and M 5 generations were found to be consistently higher than in the check varieties. Correlations between grain yield and yield attributes including seed protein per cent and protein per grain showed that these were mutagen-dependent. Grain yield showed negative correlations with protein per cent and protein per grain. However, a few mutants were found which combined high grain yield and high protein per cent. The correlation between protein per cent and protein per grain was positive and very highly significant. It was concluded that despite the high negative correlations between grain protein per cent and grain yield screening for high protein per cent in high-yielding mutants provides a great scope for the identification of the correlation breakers which combine high grain yield potential and high protein content. (author)

  2. Effects of mutagen application of sodium azide and gamma radiation in rice seeds

    International Nuclear Information System (INIS)

    Guimaraes, E.P.

    1980-01-01

    Effects of mutagen application of sodium azide and gamma radiation in rice seeds. Upland rice seeds, variety Dourado Precoce, were treated with gamma-rays and sodium azide(SA). Biological effects of these treatments were studied in the M 1 and M 2 generations. Survival number, seedling height, plant fertility and chlorophyill mutation frequencies based on mutations per 100 M 1 panicles and mutants per 100 M 2 seedlings were analysed. Among these characters, plant fertility was the most sensitive for mutagen treatments, and higher doses of gamma-rays or higher concentrations of sodium azide reduced significantly fertility of M 1 plants. The same effect as increase of concentration of sodium azide was observed when the acidity of buffer solution was increased, or when seeds were pre-treated in distilled water. The maximum chlorophyll mutation frequencies were obtained in sodium azide treatments: 40.74% in the M 1 panicles and 10.67% in the M 2 seedlings, in comparison with the maximum frequenies in gamma-irradiation of 10.39% in the M 1 panicles and 1.73% in the M 2 seedlings. (Author) [pt

  3. Rice Seed Priming with Picomolar Rutin Enhances Rhizospheric Bacillus subtilis CIM Colonization and Plant Growth.

    Directory of Open Access Journals (Sweden)

    Akanksha Singh

    Full Text Available The effect of rutin, a bioflavonoid on the growth and biofilm formation of Bacillus subtilis strain CIM was investigated. In addition to swimming, swarming, and twitching potentials of B. subtilis CIM (BS, one picomolar (1 pM of rutin was also observed to boost the biofilm forming ability of the bacterium. Bio-priming of rice seeds with BS and rutin not only augmented root and shoot lengths but also the photosynthetic pigments like chlorophyll and carotenoid. Similarly, high accumulation of phenolic and flavonoid contents was observed in the leaves. Fluorescent microscopic images revealed that BS plus rutin enhanced callose deposition in the leaves. It was also established that the least formation of reactive oxygen species in BS plus rutin treated rice plants was due to higher free radicals scavenging activity and total antioxidant potential. The results highlight chemo attractant nature of BS towards rutin, which by enhancing biofilm formation and root colonization indirectly strengthened the plants' defensive state.

  4. Simultaneous Detection of Three Bacterial Seed-Borne Diseases in Rice Using Multiplex Polymerase Chain Reaction

    Directory of Open Access Journals (Sweden)

    In Jeong Kang

    2016-12-01

    Full Text Available Burkholderia glumae (bacterial grain rot, Xanthomonas oryzae pv. oryzae (bacterial leaf blight, and Acidovorax avenae subsp. avenae (bacterial brown stripe are major seedborne pathogens of rice. Based on the 16S and 23S rDNA sequences for A. avenae subsp. avenae and B. glumae, and transposase A gene sequence for X. oryzae pv. oryzae, three sets of primers had been designed to produce 402 bp for B. glumae, 490 bp for X. oryzae, and 290 bp for A. avenae subsp. avenae with the 63°C as an optimum annealing temperature. Samples collected from naturally infected fields were detected with two bacteria, B. glumae and A. avenae subsp. avenae but X. oryzae pv. oryzae was not detected. This assay can be used to identify pathogens directly from infected seeds, and will be an effective tool for the identification of the three pathogens in rice plants.

  5. Simultaneous Detection of Three Bacterial Seed-Borne Diseases in Rice Using Multiplex Polymerase Chain Reaction.

    Science.gov (United States)

    Kang, In Jeong; Kang, Mi-Hyung; Noh, Tae-Hwan; Shim, Hyeong Kwon; Shin, Dong Bum; Heu, Suggi

    2016-12-01

    Burkholderia glumae (bacterial grain rot), Xanthomonas oryzae pv. oryzae (bacterial leaf blight), and Acidovorax avenae subsp. avenae (bacterial brown stripe) are major seedborne pathogens of rice. Based on the 16S and 23S rDNA sequences for A. avenae subsp. avenae and B. glumae , and transposase A gene sequence for X. oryzae pv. oryzae , three sets of primers had been designed to produce 402 bp for B. glumae , 490 bp for X. oryzae , and 290 bp for A. avenae subsp. avenae with the 63°C as an optimum annealing temperature. Samples collected from naturally infected fields were detected with two bacteria, B. glumae and A. avenae subsp. avenae but X. oryzae pv. oryzae was not detected. This assay can be used to identify pathogens directly from infected seeds, and will be an effective tool for the identification of the three pathogens in rice plants.

  6. Antagonism between abscisic acid and gibberellins is partially mediated by ascorbic acid during seed germination in rice.

    Science.gov (United States)

    Ye, Nenghui; Zhang, Jianhua

    2012-05-01

    The antagonism between abscisic acid (ABA) and gibberellin (GA) plays a key role in controlling seed germination, but the mechanism of antagonism during this process is not known. In the associated study, we investigated the relationship among ABA, reactive oxygen species (ROS), ascorbic acid (ASC) and GA during rice seed germination. ROS production is reduced by ABA, which hence results in decreasing ASC accumulation during imbibition. GA accumulation was also suppressed by a reduced ROS and ASC level, whereas application of exogenous ASC can partially rescue seed germination from ABA treatment. Further results show that production of ASC, which acts as a substrate in GA biosynthesis, was significantly inhibited by lycorine which thus suppressed the accumulation of GA. Consequently, expression of GA biosynthesis genes was suppressed by the low levels of ROS and ASC in ABA-treated seeds. These studies reveal a new role for ASC in mediating the antagonism between ABA and GA during seed germination in rice.

  7. Physiological quality of rice seed submitted to gamma radiation; Qualidade fisiologica de sementes de arroz submetidas a radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Helen Lucia da Cruz; Tillmann, Maria Angela Andre; Meneghello, Geri Eduardo, E-mail: helenllc@gmail.co [Universidade Federal de Pelotas (UFPel), RS (Brazil). Programa de Pos-graduacao em Ciencia e Tecnologia de Sementes; Bobrowski, Vera Lucia [Universidade Federal de Pelotas (UFPel), RS (Brazil). Dept. de Genetica; Dode, Luciana Bicca [Universidade Catolica de Pelotas (UCPel), RS (Brazil)

    2009-08-15

    The objective of this research was to evaluate the effects of the gamma radiation ({sup 60}Co) on the physiological quality of rice seeds. The research was carried out through three tests; in the first test rice seeds were irradiated at dosages of 0; 1; 2.5 and 5Gy, while for the second and third tests the seeds were subjected to accelerated aging before being irradiated. For the second test the seeds were divided into wet and dry and both groups subjected to accelerated aging previous to irradiation at dosages of 0; 1; 2.5 and 5Gy. For the third test the seeds were dried after being subjected to accelerated aging, and then irradiated at dosages of 0, 10, 25 and 50Gy. To assess the physiological effects of the gamma radiation, all seeds were tested for germination and their germination speed index recorded. Seedling growth was graded through the measurement of the lengths of the first leaf and seminal root system and total seedling dry weight, across all tests. The enzymatic activity of acid phosphatase and alpha-amylase was measured on dry seeds from the second test. The results from all tests indicate that the applied gamma radiation dosages did not cause any changes to the physiological quality of rice seeds. (author)

  8. Genetic Control of Seed Shattering in Rice by the APETALA2 Transcription Factor SHATTERING ABORTION1[C][W][OA

    Science.gov (United States)

    Zhou, Yan; Lu, Danfeng; Li, Canyang; Luo, Jianghong; Zhu, Bo-Feng; Zhu, Jingjie; Shangguan, Yingying; Wang, Zixuan; Sang, Tao; Zhou, Bo; Han, Bin

    2012-01-01

    Seed shattering is an important agricultural trait in crop domestication. SH4 (for grain shattering quantitative trait locus on chromosome 4) and qSH1 (for quantitative trait locus of seed shattering on chromosome 1) genes have been identified as required for reduced seed shattering during rice (Oryza sativa) domestication. However, the regulatory pathways of seed shattering in rice remain unknown. Here, we identified a seed shattering abortion1 (shat1) mutant in a wild rice introgression line. The SHAT1 gene, which encodes an APETALA2 transcription factor, is required for seed shattering through specifying abscission zone (AZ) development in rice. Genetic analyses revealed that the expression of SHAT1 in AZ was positively regulated by the trihelix transcription factor SH4. We also identified a frameshift mutant of SH4 that completely eliminated AZs and showed nonshattering. Our results suggest a genetic model in which the persistent and concentrated expression of active SHAT1 and SH4 in the AZ during early spikelet developmental stages is required for conferring AZ identification. qSH1 functioned downstream of SHAT1 and SH4, through maintaining SHAT1 and SH4 expression in AZ, thus promoting AZ differentiation. PMID:22408071

  9. Characterization of seeds of selected wild species of rice (Oryza) stored under high temperature and humidity conditions.

    Science.gov (United States)

    Das, Smruti; Nayak, Monalisa; Patra, B C; Ramakrishnan, B; Krishnan, P

    2010-06-01

    Wild progenitors of rice (Oryza) are an invaluable resource for restoring genetic diversity and incorporating useful traits back into cultivars. Studies were conducted to characterize the biochemical changes, including SDS-PAGE banding pattern of storage proteins in seeds of six wild species (Oryza alta, O. grandiglumis, O. meridionalis, O. nivara, O. officinalis and O. rhizomatis) of rice stored under high temperature (45 degrees C) and humidity (approixmately 100%) for 15 days, which facilitated accelerated deterioration. Under the treated conditions, seeds of different wild rice species showed decrease in per cent germination and concentrations of protein and starch, but increase in conductivity of leachate and content of sugar. The SDS-PAGE analysis of seed proteins showed that not only the total number of bands, but also their intensity in terms of thickness differed for each species under storage. The total number of bands ranged from 11 to 22, but none of the species showed all the bands. Similarity index for protein bands between the control and treated seeds was observed to be least in O. rhizomatis and O. alta, while the indices were 0.7 and 0.625 for O. officinalis and O. nivara, respectively. This study clearly showed that seed deterioration led to distinctive biochemical changes, including the presence or absence as well as altered levels of intensity of proteins. Hence, SDS-PAGE protein banding pattern can be used effectively to characterize deterioration of seeds of different wild species of rice.

  10. Hybrid breeding in wheat: technologies to improve hybrid wheat seed production.

    Science.gov (United States)

    Whitford, Ryan; Fleury, Delphine; Reif, Jochen C; Garcia, Melissa; Okada, Takashi; Korzun, Viktor; Langridge, Peter

    2013-12-01

    Global food security demands the development and delivery of new technologies to increase and secure cereal production on finite arable land without increasing water and fertilizer use. There are several options for boosting wheat yields, but most offer only small yield increases. Wheat is an inbred plant, and hybrids hold the potential to deliver a major lift in yield and will open a wide range of new breeding opportunities. A series of technological advances are needed as a base for hybrid wheat programmes. These start with major changes in floral development and architecture to separate the sexes and force outcrossing. Male sterility provides the best method to block self-fertilization, and modifying the flower structure will enhance pollen access. The recent explosion in genomic resources and technologies provides new opportunities to overcome these limitations. This review outlines the problems with existing hybrid wheat breeding systems and explores molecular-based technologies that could improve the hybrid production system to reduce hybrid seed production costs, a prerequisite for a commercial hybrid wheat system.

  11. Mapping QTL for Seed Germinability under Low Temperature Using a New High-Density Genetic Map of Rice

    Directory of Open Access Journals (Sweden)

    Ningfei Jiang

    2017-07-01

    Full Text Available Mapping major quantitative trait loci (QTL responsible for rice seed germinability under low temperature (GULT can provide valuable genetic source for improving cold tolerance in rice breeding. In this study, 124 rice backcross recombinant inbred lines (BRILs derived from a cross indica cv. Changhui 891 and japonica cv. 02428 were genotyped through re-sequencing technology. A bin map was generated which includes 3057 bins covering distance of 1266.5 cM with an average of 0.41 cM between markers. On the basis of newly constructed high-density genetic map, six QTL were detected ranging from 40 to 140 kb on Nipponbare genome. Among these, two QTL qCGR8 and qGRR11 alleles shared by 02428 could increase GULT and seed germination recovery rate after cold stress, respectively. However, qNGR1 and qNGR4 may be two major QTL affecting indica Changhui 891germination under normal condition. QTL qGRR1 and qGRR8 affected the seed germination recovery rate after cold stress and the alleles with increasing effects were shared by the Changhui 891 could improve seed germination rate after cold stress dramatically. These QTL could be a highly valuable genetic factors for cold tolerance improvement in rice lines. Moreover, the BRILs developed in this study will serve as an appropriate choice for mapping and studying genetic basis of rice complex traits.

  12. Effects of agroecological conditions and hybrid combinations on maize seed germination

    OpenAIRE

    Tabaković, M.; Glamočlija, Đ.; Jovanović, S.; Popović, V.; Simić, D.; Anđelković, S.

    2013-01-01

    Germination energy and seed germination of four maize combinations cultivated under different growing conditions were observed. Analysis of hybrid seed of four commercial combinations derived at the Maize Research Institute, Zemun Polje, grown in three locations, were done on the working sample of 4 x 100 seeds under laboratory conditions. The experimental data was processed for the mean and total variability (X and C.V.) for both seed traits and for each t...

  13. Genetics and Improvement of Bacterial Blight Resistance of Hybrid Rice in China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qi

    2009-01-01

    Since 1980s, rice breeding for resistance to bacterial blight has been rapidly progressing in China. The gene Xa4 was mainly used in three-line indica hybrid and two-line hybrid rice. The disease has been 'quiet' for 20 years in China, yet in recent years it has gradually emerged and been prevalent in fields planted with newly released rice varieties in the Changjiang River valley. Under the circumstances, scientists inevitably raised several questions: what causes the resurgence and what should we do next? And/or is resistance breeding still one of the main objectives in rice improvement? Which approach do we take on resistance breeding so that the resistance will be more durable, and the resistance gene will be used more efficiently? A combined strategy involving traditional method, molecular marker-assisted selection, and transgenic technology should bring a new era to the bacterial blight resistance hybrid rice breeding program. This review also briefly discusses and deliberates on issues related to the broadening of bacterial blight resistance, and suitable utilization of resistance genes, alternate planting of available resistance genes; and understands the virulent populations of the bacterial pathogen in China even in Asia.

  14. Effects of sodium chloride on radiation protection and modification of gamma-ray treated rice seeds

    International Nuclear Information System (INIS)

    Wang Cailian; Zhao Kongnan; Shen Mei; Xu Gang; Chen Qiufang

    1992-11-01

    The radiation protection effect of sodium chloride on dormant and germinating rice seeds treated with gamma-rays, and modification effect of sodium chloride on mutation were studied. Results show that the radiation-damage effect on seedling growth, percentage of seedling growth, percentage of seedling growth and fertility in M 1 generation is significantly enhanced with the increasing of dose. However, the seedling growth, percentage of seedling growth and fertility can be improved if the irradiated seeds are pre-treated with sodium chloride solution having concentrations of 0.05, 0.10 and 0.20 mol/L. The difference between treated group and control group is very significant. Results also show that pre-treatment and post-treatment by sodium chloride can raise the mutation frequencies of chlorophyll deficient seedlings, especially, the mutation frequency of early heading date and height is more considerably. The conclusion is that the sodium chloride, as a radiation protection agent, combined with gamma-ray treatment could reduce the effect of radiation-damage on M 1 generation and raise the mutation frequency in M 2 generation, and this result will be helpful in rice breeding

  15. Posttranscriptional regulation of alpha-amylase II-4 expression by gibberellin in germinating rice seeds.

    Science.gov (United States)

    Nanjo, Yohei; Asatsuma, Satoru; Itoh, Kimiko; Hori, Hidetaka; Mitsui, Toshiaki; Fujisawa, Yukiko

    2004-06-01

    Hormonal regulation of expression of alpha-amylase II-4 that lacks the gibberellin-response cis-element (GARE) in the promoter region of the gene was studied in germinating rice (Oryza sativa L.) seeds. Temporal and spatial expression of alpha-amylase II-4 in the aleurone layer were essentially identical to those of alpha-amylase I-1 whose gene contains GARE, although these were distinguishable in the embryo tissues at the early stage of germination. The gibberellin-responsible expression of alpha-amylase II-4 was also similar to that of alpha-amylase I-1. However, the level of alpha-amylase II-4 mRNA was not increased by gibberellin, indicating that the transcriptional enhancement of alpha-amylase II-4 expression did not occur in the aleurone. Gibberellin stimulated the accumulation of 45Ca2+ into the intracellular secretory membrane system. In addition, several inhibitors for Ca2+ signaling, such as EGTA, neomycin, ruthenium red (RuR), and W-7 prevented the gibberellin-induced expression of alpha-amylase II-4 effectively. While the gibberellin-induced expression of alpha-amylase II-4 occurred normally in the aleurone layer of a rice dwarf mutant d1 which is defective in the alpha subunit of the heterotrimeric G protein. Based on these results, it was concluded that the posttranscriptional regulation of alpha-amylase II-4 expression by gibberellin operates in the aleurone layer of germinating rice seed, which is mediated by Ca2+ but not the G protein.

  16. The Role of University Partners in the Innovation Adoption Process to Rice Seed Farmers in Aceh Province

    Directory of Open Access Journals (Sweden)

    Setia Budi

    2018-04-01

    Full Text Available The role of university partners in the innovation adoption process in the implementation of agricultural extension is very necessary to get attention to realize the success of empowering rice seed farmers. The purpose of this research is (1 to know the role of universities in the process of adopting innovation in IPB 3S seedling in Aceh Province, (2 to know the perception of farmers toward the characteristics of the innovation of IPB 3S varieties, and (3 to know the role of universities in the implementation process of extension agriculture to rice seed farmers. This research uses qualitative descriptive approach with data measurement using Likert scale. The results showed that in general the universities play significant role in innovation adoption process to rice seed farmers. The role is arranged by sequence; (1 implementing cultivation skill (2 strengthening farmer institution, (3 liaison with the government (4 guidance of transfer of technology, and (5 liaison with production market. Farmers perception on the characteristics of innovation optimum production technology package (IPB-Prima IPB 3S (1 has a relative profitability, (2 easy to try, (3 conformity, (4 observable, and (5 innovation subtly level. The role of partners in the implementation of agricultural extension in sequence (1 conformity of extension materials, (2 intensity of extension, (3 appropriateness of extension method and (4 accuracy of media usage. The university should pay attention on the mechanism of facilitating technology transfer with the use of media and appropriate extension methods to rice seed farmers. The university also should build good communication with private organizations to help farmers in terms of seed price certainty produced by rice seed farmers in Aceh Province, Indonesia.

  17. Comparison of NH4+-N and NO3--N nutrition in hybrid and conventional rice at the late growth stage

    International Nuclear Information System (INIS)

    Yang Xiaoe; Sun Xi

    1990-01-01

    The difference of NH 4 + -N/NO 3 - -N nutrition between hybrid and conventional rice varieties at the late growth stage was studied by using 15 N-tracer technique. The results showed that the nitrate fertilizer utilization efficiency by the hybrid rice after anthesis was 7.8% higher than that by the ordinary rice variety, and the nitrate fertilizer recovery fraction by the former was 13.2% greater than that by the latter. The varietal difference in NO 3 - -N uptake and utilization was almost twice as that in NH 4 + -N. It was also showed that 15 N distribution in ear of the hybrid rice was about 20% greater than that of the conventional variety, but there were no obvious differences between NO 3 - -N and NH 4 + -N. However, 15 N distribution in the lower node leaves and root was found to be significant higher with NO 3 - -N than that with NH 4 + -N in both rice varieties, particularly in the hybrid rice. Compared with NH 4 + -N, NO 3 - -N top-dressing before anthesis was observed to have much greater positive effects on the uptake of calcium and magnesium and the growth of the superficial root and the grain yield of the tested rice varieties, especially of the hybrid rice

  18. Hybrid male sterility in rice controlled by interaction between divergent alleles of two adjacent genes.

    Science.gov (United States)

    Long, Yunming; Zhao, Lifeng; Niu, Baixiao; Su, Jing; Wu, Hao; Chen, Yuanling; Zhang, Qunyu; Guo, Jingxin; Zhuang, Chuxiong; Mei, Mantong; Xia, Jixing; Wang, Lan; Wu, Haibin; Liu, Yao-Guang

    2008-12-02

    Sterility is common in hybrids between divergent populations, such as the indica and japonica subspecies of Asian cultivated rice (Oryza sativa). Although multiple loci for plant hybrid sterility have been identified, it remains unknown how alleles of the loci interact at the molecular level. Here we show that a locus for indica-japonica hybrid male sterility, Sa, comprises two adjacent genes, SaM and SaF, encoding a small ubiquitin-like modifier E3 ligase-like protein and an F-box protein, respectively. Most indica cultivars contain a haplotype SaM(+)SaF(+), whereas all japonica cultivars have SaM(-)SaF(-) that diverged by nucleotide variations in wild rice. Male semi-sterility in this heterozygous complex locus is caused by abortion of pollen carrying SaM(-). This allele-specific gamete elimination results from a selective interaction of SaF(+) with SaM(-), a truncated protein, but not with SaM(+) because of the presence of an inhibitory domain, although SaM(+) is required for this male sterility. Lack of any one of the three alleles in recombinant plants does not produce male sterility. We propose a two-gene/three-component interaction model for this hybrid male sterility system. The findings have implications for overcoming male sterility in inter-subspecific hybrid rice breeding.

  19. Seed Priming Improves Agronomic Trait Performance under Flooding and Non-flooding Conditions in Rice with QTL SUB1

    Directory of Open Access Journals (Sweden)

    Ramni Kumar SARKAR

    2012-12-01

    Full Text Available Farmers in South East Asia are adopting rice crop establishment methods from transplanting to direct wet or dry seeding as it requires less labour and time and comparatively less energy than transplanting. In contrast to irrigated condition, in rainfed lowland, direct seeding is a common practice. Early flooding controls weeds but decreases seedling establishment in direct seeded rice. Anaerobic germination is an important trait to counteract damages caused by early flooding. Management options which can help in crop establishment and improve crop growth under flooding might remove the constraints related to direct seeding. The investigation was carried out with two near isogenic lines Swarna and Swarna-Sub1. Swarna-Sub1 is tolerant to submergence whereas Swarna is susceptible. Seed priming was done with water and 2% Jamun (Syzygium cumini leaf extract, and it improved seedling establishment under flooding. Acceleration of growth occurred due to seed pretreatment, which resulted longer seedling and greater accumulation of biomass. Seed priming greatly hastened the activities of total amylase and alcohol dehydrogenase in Swarna-Sub1 than in Swarna. Swarna-Sub1 outperformed Swarna when the plants were cultivated under flooding. Weed biomass decreased significantly under flooding compared to non-flooding conditions. Seed priming had positive effects on yield and yield attributing parameters both under non-flooding and early flooding conditions.

  20. Expression patterns of ABA and GA metabolism genes and hormone levels during rice seed development and imbibition: a comparison of dormant and non-dormant rice cultivars.

    Science.gov (United States)

    Liu, Yang; Fang, Jun; Xu, Fan; Chu, Jinfang; Yan, Cunyu; Schläppi, Michael R; Wang, Youping; Chu, Chengcai

    2014-06-20

    Seed dormancy is an important agronomic trait in cereals. Using deep dormant (N22), medium dormant (ZH11), and non-dormant (G46B) rice cultivars, we correlated seed dormancy phenotypes with abscisic acid (ABA) and gibberellin (GA) metabolism gene expression profiles and phytohormone levels during seed development and imbibition. A time course analysis of ABA and GA content during seed development showed that N22 had a high ABA level at early and middle seed developmental stages, while at late developmental stage it declined to the level of ZH11; however, its ABA/GA ratio maintained at a high level throughout seed development. By contrast, G46B had the lowest ABA content during seed development though at early developmental stage its ABA level was close to that of ZH11, and its ABA/GA ratio peaked at late developmental stage that was at the same level of ZH11. Compared with N22 and G46B, ZH11 had an even and medium ABA level during seed development and its ABA/GA ratio peaked at the middle developmental stage. Moreover, the seed development time-point having high ABA/GA ratio also had relatively high transcript levels for key genes in ABA and GA metabolism pathways across three cultivars. These indicated that the embryo-imposed dormancy has been induced before the late developmental stage and is determined by ABA/GA ratio. A similar analysis during seed imbibition showed that ABA was synthesized in different degrees for the three cultivars. In addition, water uptake assay for intact mature seeds suggested that water could permeate through husk barrier into seed embryo for all three cultivars; however, all three cultivars showed distinct colors by vanillin-staining indicative of the existence of flavans in their husks, which are dormancy inhibition compounds responsible for the husk-imposed dormancy. Copyright © 2014. Published by Elsevier Ltd.

  1. Characterization of 140 Japanese and world rice collections cultivated in Nihonmatsu-city in Fukushima in terms of radiocesium activity concentrations in seed grains and straws to explore rice cultivars with low radiocesium accumulation

    International Nuclear Information System (INIS)

    Katsuhiro Kojima; Djedidi Salem

    2017-01-01

    We studied varietal difference in radiocesium accumulation by using Japanese and World rice collection for future development of low accumulation varieties. As a result, the radiocesium activity concentration varied by 12- and 22-fold in seed grains and straws, respectively. When we examined the seed grain to straw ratio of radiocesium activity concentration, paddy rice cultivars of Japonica sub-species showed a lower result than Indica and Javanica paddy rice cultivars. These observations suggest that the Japonica paddy rice cultivars may have the property of repressing radioactive cesium translocation to edible parts. (author)

  2. Evolution of rice and pulse varieties with improved quality through induced mutations. Part of a coordinated programme on the use of nuclear techniques for seed protein improvement

    International Nuclear Information System (INIS)

    Mia, M.M.

    1980-03-01

    Three mutant varieties, 16 hybrids of advanced generation, 6 recommended varieties and many local collections of rice in Bangladesh were screened for protein content. The 25 varieties or strains showed a variation of protein content between 8.9 - 11.7% and also wide ranges of variation in amylose content, starch-iodine-blue value and water absorption by grain. Amino acid compositions of some promising varieties were also investigated. 60 rice germplasms tested also showed a wide range of variation in protein content (6-13%) and variations of other seed characteristics. 3000 local collections showed a variation range of 5-13% protein content. Mutation breedings were carried out on chickpeas and lentils on a large scale. Dry seed was treated with 60 Co gamma ray and mutants were detected, selected, particularly for high protein content, and evaluated in M 2 -M 8 generations. Of the 10 selected mutant lines of each of the pulses, variations of various agronomic characters were observed. However, induced variation in protein content was only remarkable in chickpea. The most promising chickpea mutant showed 19% higher yield and 12% higher protein content than the mother variety, and was proposed to be released as a variety

  3. TALEN-Based Mutagenesis of Lipoxygenase LOX3 Enhances the Storage Tolerance of Rice (Oryza sativa Seeds.

    Directory of Open Access Journals (Sweden)

    Lei Ma

    Full Text Available The deterioration of rice grain reduces the quality of rice, resulting in serious economic losses for farmers. Lipoxygenases (LOXs catalyze the dioxygenation of polyunsaturated fatty acids with at least one cis,cis-1,4-pentadiene to form hydroperoxide, which is a major factor influencing seed longevity and viability. Recently, genome editing, an essential tool employed in reverse genetics, has been used experimentally to investigate basic plant biology or to modify crop plants for the improvement of important agricultural traits. In this study, we performed targeted mutagenesis in rice using transcription activator-like effector nucleases (TALENs to improve seed storability. A modified ligation-independent cloning method (LIC was employed to allow for the quick and efficient directional insertion of TALEN monomer modules into destination vectors used in plants. We demonstrated the feasibility and flexibility of the technology by developing a set of modular vectors for genome editing. After construction and validation, the TALEN pairs were used to create stable transgenic rice lines via Agrobacterium-mediated transformation. One heterozygous mutant (4% was recovered from 25 transgenic NPTII-resistant lines, and the mutation was transmitted to the next generation. Further molecular and protein level experiments verified LOX3 deficiency and demonstrated the improvement of seed storability. Our work provides a flexible genome editing tool for improving important agronomic traits, as well as direct evidence that Lox3 has only a limited impact on seed longevity.

  4. TALEN-Based Mutagenesis of Lipoxygenase LOX3 Enhances the Storage Tolerance of Rice (Oryza sativa) Seeds.

    Science.gov (United States)

    Ma, Lei; Zhu, Fugui; Li, Zhenwei; Zhang, Jianfu; Li, Xin; Dong, Jiangli; Wang, Tao

    2015-01-01

    The deterioration of rice grain reduces the quality of rice, resulting in serious economic losses for farmers. Lipoxygenases (LOXs) catalyze the dioxygenation of polyunsaturated fatty acids with at least one cis,cis-1,4-pentadiene to form hydroperoxide, which is a major factor influencing seed longevity and viability. Recently, genome editing, an essential tool employed in reverse genetics, has been used experimentally to investigate basic plant biology or to modify crop plants for the improvement of important agricultural traits. In this study, we performed targeted mutagenesis in rice using transcription activator-like effector nucleases (TALENs) to improve seed storability. A modified ligation-independent cloning method (LIC) was employed to allow for the quick and efficient directional insertion of TALEN monomer modules into destination vectors used in plants. We demonstrated the feasibility and flexibility of the technology by developing a set of modular vectors for genome editing. After construction and validation, the TALEN pairs were used to create stable transgenic rice lines via Agrobacterium-mediated transformation. One heterozygous mutant (4%) was recovered from 25 transgenic NPTII-resistant lines, and the mutation was transmitted to the next generation. Further molecular and protein level experiments verified LOX3 deficiency and demonstrated the improvement of seed storability. Our work provides a flexible genome editing tool for improving important agronomic traits, as well as direct evidence that Lox3 has only a limited impact on seed longevity.

  5. Overcoming inter-subspecific hybrid sterility in rice by developing indica-compatible japonica lines.

    Science.gov (United States)

    Guo, Jie; Xu, Xiaomei; Li, Wentao; Zhu, Wenyin; Zhu, Haitao; Liu, Ziqiang; Luan, Xin; Dai, Ziju; Liu, Guifu; Zhang, Zemin; Zeng, Ruizhen; Tang, Guang; Fu, Xuelin; Wang, Shaokui; Zhang, Guiquan

    2016-06-01

    Rice (Oryza sativa L.) is an important staple crop. The exploitation of the great heterosis that exists in the inter-subspecific crosses between the indica and japonica rice has long been considered as a promising way to increase the yield potential. However, the male and female sterility frequently occurred in the inter-subspecific hybrids hampered the utilization of the heterosis. Here we report that the inter-subspecific hybrid sterility in rice is mainly affected by the genes at Sb, Sc, Sd and Se loci for F1 male sterility and the gene at S5 locus for F1 female sterility. The indica-compatible japonica lines (ICJLs) developed by pyramiding the indica allele (S-i) at Sb, Sc, Sd and Se loci and the neutral allele (S-n) at S5 locus in japonica genetic background through marker-assisted selection are compatible with indica rice in pollen fertility and in spikelet fertility. These results showed a great promise of overcoming the inter-subspecific hybrid sterility and exploiting the heterosis by developing ICJLs.

  6. Do rice suspension-cultured cells treated with abscisic acid mimic developing seeds?

    Science.gov (United States)

    Matsuno, Koya; Fujimura, Tatsuhito

    2015-08-01

    Starch synthesis is activated in the endosperm during seed development and also in rice suspension cells cultured with abscisic acid. In the anticipation that the mechanisms of starch synthesis are similar between the endosperm and the suspension cells cultured with abscisic acid, expression of genes involved in starch synthesis was evaluated in the suspension cells after abscisic acid treatment. However, it was found that the regulatory mechanism of starch synthesis in the suspension cells cultured with abscisic acid was different from that in developing seeds. Expression analyses of genes involved in oil bodies, which accumulate in the embryo and aleurone layer, and seed storage proteins, which accumulate mainly in the endosperm, showed that the former were activated in the suspension cells cultured with abscisic acid, but the latter were not. Master regulators for embryogenesis, OsVP1 (homologue of AtABI3) and OsLFL1 (homologue of AtFUS3 or AtLFL2), were expressed in the suspension cells at levels comparable to those in the embryo. From these results, it is suggested that interactions between regulators and abscisic acid control the synthesis of phytic acid and oil bodies in the cultured cells and embryo. We suggest that the system of suspension cells cultured with abscisic acid helps to reveal the mechanisms of phytic acid and oil body synthesis in embryo.

  7. Absence of storage effects on radiation damage after thermal neutron irradiation of dry rice seeds

    Energy Technology Data Exchange (ETDEWEB)

    Kowyama, Y. [Mie Univ., Tsu (Japan); Saito, M.; Kawase, T.

    1987-09-15

    Storage effects on dry rice seeds equilibrated to 6.8% moisture content were examined after irradiation with X-rays of 5, 10, 20 and 40 kR and with thermal neutrons of 2.1, 4.2, 6.3 and 8.4×10{sup 13}N{sub th}/cm{sup 2}. Reduction in root growth was estimated from dose response curves after storage periods of 1 hr to 21 days. The longer the storage period, the greater enhancement of radiation damages in X-irradiated seeds. There were two components in the storage effect, i. e., a rapid increase of radiosensitivity within the first 24 hr and a slow increase up to 21 days. An almost complete absence of a storage effect was observed after thermal neutron exposure, in spite of considerably high radioactivities of the induced nuclides, {sup 56}Mn, {sup 42}K and {sup 24}Na, which were detected from gamma-ray spectrometry of the irradiated seeds. The present results suggest that the contributions of gamma-rays from the activated nuclides and of inherent contaminating gamma-rays are little or negligible against the neutron-induced damage, and that the main radiobiological effects of thermal neutrons are ascribed to in situ radiations, i, e., heavy particles resulting from neutron-capture reaction of atom. A mechanism underlying the absence of storage effect after thermal neutron irradiation was briefly discussed on the basis of radical formation and decay. (author)

  8. New hybrid rice cultivar 'Zhefuliangyou 12' with improved grain quality produced by leaf color marker-labeled male sterile line and mutant with enhanced tillers and improved grain quality

    International Nuclear Information System (INIS)

    Mei Shufang; Zhao Hua; Wang Yongqiang; Shu Xiaoli; Wu Dianxing

    2013-01-01

    In order to breed high yielding and good grain quality new variety with controllable seed purity, hybrid rice 'Zhefuliangyou 12' was produced by green-revertible albino leaf color marker-labeled two-line male sterile line 'NHR111S' and mutant 'ZF-2' with enhanced tillers and improved grain quality, which was characterized by improved grain quality, rice blast resistance and lodging resistance. Breeding protocol, characteristics, and high yielding cultivation techniques of 'Zhefuliangyou 12' were briefly introduced in the current paper. (authors)

  9. Long-Term No-Tillage Direct Seeding Mode for Water-Saving and Drought-Resistance Rice Production in Rice-Rapeseed Rotation System

    Directory of Open Access Journals (Sweden)

    Xing-bin DU

    2014-07-01

    Full Text Available To study the effects of long-term no-tillage direct seeding mode on rice yield and the soil physiochemical property in a rice-rapeseed rotation system, a comparative experiment with a water-saving and drought-resistance rice (WDR variety and a double low rapeseed variety as materials was conducted under no-tillage direct seeding (NTDS mode and conventional tillage direct seeding (CTDS mode for four years, using the CTDS mode as the control. Compared with the CTDS mode, the actual rice yield of WDR decreased by 8.10% at the first year, whereas the plant height, spikelet number per panicle, spikelet fertility, 1000-grain weight, grain yield, actual yield, and harvest index increased with no-tillage years, which led to the actual yield increase by 6.49% at the fourth year. Correlation analysis showed that the panicle length was significantly related to the actual yield of WDR. Compared with the CTDS mode in terms of the soil properties, the pH value of the NTDS mode decreased every year, whereas the contents of soil organic matter and total N of the NTDS mode increased. In the 0–5 cm layer of the NTDS mode, the soil bulk decreased, whereas the contents of soil organic matter, total N, and available N increased. In the 5–20 cm layer of the NTDS mode, the available N and K decreased, whereas the soil bulk, contents of soil organic matter, and total N increased. In summary, the NTDS mode increased the rice yield, and could improve the paddy soil fertility of the top layer.

  10. Yield and size of oyster mushroom grown on rice/wheat straw basal substrate supplemented with cotton seed hull.

    Science.gov (United States)

    Yang, Wenjie; Guo, Fengling; Wan, Zhengjie

    2013-10-01

    Oyster mushroom (Pleurotus ostreatus) was cultivated on rice straw basal substrate, wheat straw basal substrate, cotton seed hull basal substrate, and wheat straw or rice straw supplemented with different proportions (15%, 30%, and 45% in rice straw substrate, 20%, 30%, and 40% in wheat straw substrate) of cotton seed hull to find a cost effective substrate. The effect of autoclaved sterilized and non-sterilized substrate on growth and yield of oyster mushroom was also examined. Results indicated that for both sterilized substrate and non-sterilized substrate, oyster mushroom on rice straw and wheat basal substrate have faster mycelial growth rate, comparatively poor surface mycelial density, shorter total colonization period and days from bag opening to primordia formation, lower yield and biological efficiency, lower mushroom weight, longer stipe length and smaller cap diameter than that on cotton seed hull basal substrate. The addition of cotton seed hull to rice straw and wheat straw substrate slowed spawn running, primordial development and fruit body formation. However, increasing the amount of cotton seed hull can increase the uniformity and white of mycelium, yield and biological efficiency, and increase mushroom weight, enlarge cap diameter and shorten stipe length. Compared to the sterilized substrate, the non-sterilized substrate had comparatively higher mycelial growth rate, shorter total colonization period and days from bag opening to primordia formation. However, the non-sterilized substrate did not gave significantly higher mushroom yield and biological efficiency than the sterilized substrate, but some undesirable characteristics, i.e. smaller mushroom cap diameter and relatively long stipe length.

  11. Enrichment of rice-based extrudates with Cactus Opuntia dillenii seed powder: a novel source of fiber and antioxidants.

    Science.gov (United States)

    Rayan, Ahmed M; Morsy, Noha E; Youssef, Khaled M

    2018-02-01

    The present study investigated the effects of adding the powder of cactus Opuntia dillenii ( O. dillenii ) seeds on the functional properties, fiber, antioxidants and acceptability of rice-based extrudates. The control blend consisting basically of rice flour was replaced with O. dillenii seed powder at 2, 4, 6, 8, 10, 15 and 20% then extruded at the optimum processing conditions. The extruded products were evaluated for their chemical composition, functional properties, color attributes, antioxidant activity and sensory characteristics. The results revealed that adding O. dillenii seeds powder enhanced the fiber, phenolics, flavonoid contents and antioxidant activity of extrudates. Expansion, bulk density and breaking strength were significantly decreased, while water absorption index, water solubility index and oil absorption index were significantly increased compared to the control. Furthermore, the mean scores of sensory evaluation indicated clear improvements in all tested sensory attributes, which significantly increased by increasing the level of O. dillenii seed powder up to 15%. The results confirmed that O. dillenii seed powder could be incorporated in rice to develop snack products of acceptable functional, nutritional and sensory properties.

  12. A study on flexural and water absorption of surface modified rice husk flour/E-glass/polypropylene hybrid composite

    Science.gov (United States)

    Rassiah, K.; Sin, T. W.; Ismail, M. Z.

    2016-10-01

    This work is to study the effects of rice husk (RH)/E-Glass (EG)/polypropylene (PP) hybrid composites in terms of flexural and water absorption properties. The tests conducted are the flexural test and also the water absorption test using two types of water: distilled and sea water. The hybrid composites are prepared with various ratios of fibre weight fractions and the rice husk is treated using 2% Sodium Hydroxide (NaOH) to improve interaction and adhesion between the non-polar matrix and the polar lignocellulosic fibres. It was found that the content of rice husk/E-Glass fillers affected the structural integrity and flexural properties of hybrid composites. In addition, a higher ratio of rice husk contributes to higher water absorption in the hybrid composites.

  13. Hybrid male sterility in rice is due to epistatic interactions with a pollen killer locus.

    Science.gov (United States)

    Kubo, Takahiko; Yoshimura, Atsushi; Kurata, Nori

    2011-11-01

    In intraspecific crosses between cultivated rice (Oryza sativa) subspecies indica and japonica, the hybrid male sterility gene S24 causes the selective abortion of male gametes carrying the japonica allele (S24-j) via an allelic interaction in the heterozygous hybrids. In this study, we first examined whether male sterility is due solely to the single locus S24. An analysis of near-isogenic lines (NIL-F(1)) showed different phenotypes for S24 in different genetic backgrounds. The S24 heterozygote with the japonica genetic background showed male semisterility, but no sterility was found in heterozygotes with the indica background. This result indicates that S24 is regulated epistatically. A QTL analysis of a BC(2)F(1) population revealed a novel sterility locus that interacts with S24 and is found on rice chromosome 2. The locus was named Epistatic Factor for S24 (EFS). Further genetic analyses revealed that S24 causes male sterility when in combination with the homozygous japonica EFS allele (efs-j). The results suggest that efs-j is a recessive sporophytic allele, while the indica allele (EFS-i) can dominantly counteract the pollen sterility caused by S24 heterozygosity. In summary, our results demonstrate that an additional epistatic locus is an essential element in the hybrid sterility caused by allelic interaction at a single locus in rice. This finding provides a significant contribution to our understanding of the complex molecular mechanisms underlying hybrid sterility and microsporogenesis.

  14. Seed Germination Behaviors Of Some Aerobic Rice Cultivars Oryza Sativa L After Priming With Polyethylene Glycol-8000 Peg-8000

    Directory of Open Access Journals (Sweden)

    Elkheir H.A

    2015-08-01

    Full Text Available Seed Priming Is Famous Technique To Accelerate Seed Germination Behaviors. This Experiment Was Conducted To Study The Effect Of Polyethylene Glycol-8000 Peg-8000 As Priming Agent On Seed Germination Behavior Of Some Aerobic Rice Cultivars Oryza Sativa L. Experiment Was Carried Out By Using Two-Factor Three Aerobic Rice Cultivars And Peg With Four Replications Which Arranged In Factorial System Design And Conducted With Completely Randomized Design. The Factor Was Varieties Which Were Inpago 8 V1 Ir64 V2 And Situbagendit V3 Combine With 4 Levels Of Peg Concentrations 0100 And 200 Gl-1 And Control With No Treatment. Experiment Was Repeated 4 Times So Total Number Of Experimental Units Were 48. Germination Parameters Measured Were Germination Percentage Germination Index Days Of 50 Germination Seedling Fresh Weight Mg Seedling Shoot Fresh Weight And Root Fresh Weight Mg Seedling Dry Weigh Mg Seedling Shoot Dry Weight And Root Dry Weight Mg ShootRoot Ratio Seedling Length Cm Seedling Root Length Cm And Shoot Length Cm And Seed Vigor Index. The Results Indicated That Seed Priming Significantly Affected Germination Behaviors Compared With Control Depending Upon Varieties. The Highest Germination Was Obtained Under Laboratory And Greenhouse Condition By The Treatment Of Peg 200 G L-1 On The Situbagendit And Ir-64 Variety 90.25 And 93.33 Respectively Compared To Control In Inpago-8 In Both Laboratory 75.75 And Greenhouse 80 . As Implementation To Increase Seed And Seedling Vigor Of Rice It Is A Best Practice To Use Peg Priming With 200 Gl-1 Solutions Depend Upon Varietal Response And We Suggest That More Research About The Effect Of Peg As Seed Priming Techniques On Seed Germination Behavior Of Many Grain Crops Is Needed To Confirm The Methodology.

  15. Synthesis of geopolymer from rice husk ash for biodiesel production of Calophyllum inophyllum seed oil

    Science.gov (United States)

    Saputra, E.; Nugraha, M. W.; Helwani, Z.; Olivia, M.; Wang, S.

    2018-04-01

    In this work, geopolymer was prepared from rice husk ash (RHA) made into sodium silicate then synthesized by reacting metakaolin, NaOH, and water. The catalyst was characterized using Scanning Electron Microscopy (SEM), Energy-dispersive X-Ray analysis (EDX), Brunaeur Emmet Teller (BET), and basic strength. Then, the catalyst used for transesterification of Calophyllum inophyllum seed oil in order to produce biodiesel. The variation of process variables conducted to assess the effect on the yield of biodiesel. The highest yield obtained 87.68% biodiesel with alkyl ester content 99.29%, density 866 kg/m3, viscosity 4.13 mm2/s, the acid number of 0.42 mg-KOH/g biodiesel and the flash point 140 °C. Generally, variations of %w/w catalyst provides a dominant influence on the yield response of biodiesel. The physicochemical properties of the produced biodiesel comply with ASTM standard specifications.

  16. Suppression or knockout of SaF/SaM overcomes the Sa-mediated hybrid male sterility in rice

    Institute of Scientific and Technical Information of China (English)

    Yongyao Xie; Baixiao Niu; Yunming Long; Gousi Li; Jintao Tang; Yaling Zhang; Ding Ren; Yao-Guang Liu; Letian Chen

    2017-01-01

    Hybrids between the indica and japonica subspecies of rice (Oryza sativa) are usually sterile, which hinders utilization of heterosis in the inter-subspecific hybrid breeding. The complex locus Sa comprises two adjacently located genes, SaF and SaM, which interact to cause abortion of pollen grains carrying the japonica allele in japonica-indica hybrids. Here we showed that silencing of SaF or SaM by RNA interference restored male fertility in indica-japonica hybrids with heterozygous Sa. We further used clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-based genome editing to knockout the SaF and SaM alleles, respectively, of an indica rice line to create hybrid-compatible lines. The resultant artificial neutral alleles did not affect pollen viability and other agricultural traits, but did break down the reproductive barrier in the hybrids. We found that some rice lines have natural neutral allele Sa-n, which was compatible with the typical japonica or indica Sa alleles in hybrids. Our results demonstrate that SaF and SaM are required for hybrid male sterility, but are not essential for pollen development. This study provides effective approaches for the generation of hybrid-compatible lines by knocking out the Sa locus or using the natural Sa-n allele to overcome hybrid male sterility in rice breeding.

  17. Suppression or knockout of SaF/SaM overcomes the Sa-mediated hybrid male sterility in rice.

    Science.gov (United States)

    Xie, Yongyao; Niu, Baixiao; Long, Yunming; Li, Gousi; Tang, Jintao; Zhang, Yaling; Ren, Ding; Liu, Yao-Guang; Chen, Letian

    2017-09-01

    Hybrids between the indica and japonica subspecies of rice (Oryza sativa) are usually sterile, which hinders utilization of heterosis in the inter-subspecific hybrid breeding. The complex locus Sa comprises two adjacently located genes, SaF and SaM, which interact to cause abortion of pollen grains carrying the japonica allele in japonica-indica hybrids. Here we showed that silencing of SaF or SaM by RNA interference restored male fertility in indica-japonica hybrids with heterozygous Sa. We further used clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-based genome editing to knockout the SaF and SaM alleles, respectively, of an indica rice line to create hybrid-compatible lines. The resultant artificial neutral alleles did not affect pollen viability and other agricultural traits, but did break down the reproductive barrier in the hybrids. We found that some rice lines have natural neutral allele Sa-n, which was compatible with the typical japonica or indica Sa alleles in hybrids. Our results demonstrate that SaF and SaM are required for hybrid male sterility, but are not essential for pollen development. This study provides effective approaches for the generation of hybrid-compatible lines by knocking out the Sa locus or using the natural Sa-n allele to overcome hybrid male sterility in rice breeding. © 2017 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc. © 2017 Institute of Botany, Chinese Academy of Sciences.

  18. EPR spin probe investigation of irradiated wheat, rice and sunflower seeds

    Energy Technology Data Exchange (ETDEWEB)

    Paktas, Dilek Dadayl [Department of Physics, Faculty of Art and Science, Zonguldak Karaelmas University, 67100 Zonguldak (Turkey)]. E-mail: dadayli@karaelmas.edu.tr; Suennetcioglu, M. Maral [Department of Physics Engineering, Hacettepe University, 06532 Beytepe, Ankara (Turkey)

    2007-01-15

    TEMPO and 4-nitro-TEMPO spin probes were used to monitor dose-dependent changes in the EPR spectra of irradiated wheat and rice embryos and sunflower embryo parts. Rice embryos were studied in the 233-293 K temperature range using 4-nitro-TEMPO. TEMPAMINE, TEMPYO and DTBN spin probes were also studied for their applicability in the determination of irradiated seeds. All the recorded spectra were simulated, and spectral parameters and partition of the probes among various domains were determined. Despite the contribution of the signal from extracellular regions, it was possible to detect the changes in the water/lipid ratios with dose. The hydrophilic character of the probe alone was not sufficient to distinguish the different doses of irradiation. Line widths and rotational correlation times of various domains within embryo also play an important role. Partition after dehydration was another measure in the selection of the suitable probes for irradiation studies. Better results were obtained in dehydrated embryos for the probes preferring lipid bodies.

  19. Spatial and Spectral Hybrid Image Classification for Rice Lodging Assessment through UAV Imagery

    Directory of Open Access Journals (Sweden)

    Ming-Der Yang

    2017-06-01

    Full Text Available Rice lodging identification relies on manual in situ assessment and often leads to a compensation dispute in agricultural disaster assessment. Therefore, this study proposes a comprehensive and efficient classification technique for agricultural lands that entails using unmanned aerial vehicle (UAV imagery. In addition to spectral information, digital surface model (DSM and texture information of the images was obtained through image-based modeling and texture analysis. Moreover, single feature probability (SFP values were computed to evaluate the contribution of spectral and spatial hybrid image information to classification accuracy. The SFP results revealed that texture information was beneficial for the classification of rice and water, DSM information was valuable for lodging and tree classification, and the combination of texture and DSM information was helpful in distinguishing between artificial surface and bare land. Furthermore, a decision tree classification model incorporating SFP values yielded optimal results, with an accuracy of 96.17% and a Kappa value of 0.941, compared with that of a maximum likelihood classification model (90.76%. The rice lodging ratio in paddies at the study site was successfully identified, with three paddies being eligible for disaster relief. The study demonstrated that the proposed spatial and spectral hybrid image classification technology is a promising tool for rice lodging assessment.

  20. Identifying molecular markers associated with stigma characteristics in rice

    Science.gov (United States)

    Stigma characteristics play essential roles in hybrid seed production of rice and marker-assisted breeding plays essential role because they are quantitatively inherited with single-flowered perfect spikelet. Ninety four accessions originated from 47 countries were selected from the USDA rice core c...

  1. Effects of genetically modified herbicide-tolerant (GMHT) rice on ...

    African Journals Online (AJOL)

    GREGORY

    2010-05-24

    May 24, 2010 ... To detect potential changes in properties of weed communities in fields of ... the hypothesis that the difference between the effect of GMHT rice Bar68-1 ... seed production, to raise purity of parents of hybrid rice, ... 3. 120. 20 × 20 cm. 2007. B. May 18. Jun 5. Aug 29 Aug 5, Sept 4. ..... part of agrobiodiversity.

  2. Effects of lanthanum and acid rain stress on the bio-sequestration of lanthanum in phytoliths in germinated rice seeds

    Science.gov (United States)

    Si, Yong; Wang, Lihong; Huang, Xiaohua

    2018-01-01

    REEs in the environment can be absorbed by plants and sequestered by plant phytoliths. Acid rain can directly or indirectly affect plant physiological functions. Currently, the effects of REEs and acid rain on phytolith-REEs complex in plants are not yet fully understood. In this study, a high-silicon accumulation crop, rice (Oryza sativa L.), was selected as a representative of plants, and orthogonal experiments were conducted under various levels of lanthanum [La(III)] and pH. The results showed that various La(III) concentrations could significantly improve the efficiency and sequestration of phytolith La(III) in germinated rice seeds. A pH of 4.5 promoted phytolith La(III) sequestration, while a pH of 3.5 inhibited sequestration. Compared with the single treatment with La(III), the combination of La(III) and acid rain inhibited the efficiency and sequestration of phytolith La(III). Correlation analysis showed that the efficiency of phytolith La(III) sequestration had no correlation with the production of phytolith but was closely correlated with the sequestration of phytolith La(III) and the physiological changes of germinated rice seeds. Phytolith morphology was an important factor affecting phytolith La(III) sequestration in germinated rice seeds, and the effect of tubes on sequestration was more significant than that of dumbbells. This study demonstrated that the formation of the phytolith and La(III) complex could be affected by exogenous La(III) and acid rain in germinated rice seeds. PMID:29763463

  3. Two neutral alleles of improving male gamete abortion in indica-japonica hybrid rice

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@It was difficult to use the pronounced heterosis of indica-japonica hybrids rice due to the panicle sterility caused by male and female gamete abortion. The female gamete abortion in most of subspecific hybrids could be solved by using an abortion-neutral gene S5-n, a wide compatibility gene. The problem of male gamete abortion indicated by distorted segregation of marker genes remained to be studied. Segregation distortion via male gamete had been reported on chromosomes 3, 7, 8, 11, and 12.

  4. Dwarf Rice Mutant Derived from 0.2 kGy Gamma Rays Irradiated Seeds of Atomita 4 Variety

    International Nuclear Information System (INIS)

    Sobrizal; Sutisna Sanjaya; Carkum; Mohamad Ismachin

    2004-01-01

    Dwarf rice mutant was obtained when Atomita 4 seeds were irradiated by 0.2 kGy gamma rays. The results of segregation analyses in F2 populations and F3 lines derived from reciprocal crosses of mutant and Atomita 4 suggested that the dwarf was controlled by a single recessive gene. This gene was not located on rice cytoplasmic genome but on nuclear genome. The gene for dwarf obtained in this study tentatively could be assumed as a new finding until the allelic relationships with other dwarf genes are verified. (author)

  5. Prokaryotic Expression, Purification and Characterization of a Novel Rice Seed Lipoxygenase Gene OsLOX1

    Directory of Open Access Journals (Sweden)

    Ren Wang

    2008-06-01

    Full Text Available Lipoxygenase (LOX, EC1.13.11.12 is a key enzyme during the degradation of lipids in animals and even plants, and also the first key enzyme responsible for the biosynthesis of jasmonate. To purify and characterize the OsLOX1 gene from rice seeds, the entire coding region of the OsLOX1 gene was inserted into an expression vector pET30a(+ and transformed into Escherichia coli BL21 (DE3. Expression of the fusion protein was successfully induced by isopropyl-β-D- thiogalactopyranoside (IPTG and the purified recombinant protein was obtained by His·Bind® Kits. Further assay showed that the purified recombinant protein exhibited the LOX activity. The optimum pH was 4.8 (acetate buffer and the optimum temperature was 30°C for the above enzyme. Thus, the recombinant might confer an available usage for the synthesis of jasmonate in vitro, and also provides a possibility for elucidating the inter-relationship between the primary structure of the plant seed lipoxygenase protein and its physiological functions.

  6. Hybrid ICA-Seed-Based Methods for fMRI Functional Connectivity Assessment: A Feasibility Study

    Directory of Open Access Journals (Sweden)

    Robert E. Kelly

    2010-01-01

    Full Text Available Brain functional connectivity (FC is often assessed from fMRI data using seed-based methods, such as those of detecting temporal correlation between a predefined region (seed and all other regions in the brain; or using multivariate methods, such as independent component analysis (ICA. ICA is a useful data-driven tool, but reproducibility issues complicate group inferences based on FC maps derived with ICA. These reproducibility issues can be circumvented with hybrid methods that use information from ICA-derived spatial maps as seeds to produce seed-based FC maps. We report results from five experiments to demonstrate the potential advantages of hybrid ICA-seed-based FC methods, comparing results from regressing fMRI data against task-related a priori time courses, with “back-reconstruction” from a group ICA, and with five hybrid ICA-seed-based FC methods: ROI-based with (1 single-voxel, (2 few-voxel, and (3 many-voxel seed; and dual-regression-based with (4 single ICA map and (5 multiple ICA map seed.

  7. The inhibitory effect of the various seed coating substances against rice seed borne fungi and their shelf-life during storage.

    Science.gov (United States)

    Thobunluepop, Pitipong

    2009-08-15

    Presently, chemical seed treatments are in discussion due to their directly or indirectly impacts on human health or other living organisms. They may also negatively affect the ecosystem and the food chain. In rice seeds, chemicals may cause phytotoxic effects including seed degradation. Eugenol is the main component of clove (Eugenia caryophillis) oil, which was proved to act simultaneously as bactericide, virocide and especially fungicide. The in vitro study was aimed to compare the inhibitory effect of the following seed treatment substances against seed borne fungi and their shelf-life during 12 months of storage; conventional captan (CA), chitosan-lignosulphonate polymer (CL), eugenol incorporated into chitosan-lignosulphonate polymer (E+CL) and control (CO). The obtained results of fungi inhibition were classified in three groups, which showed at first that CA treatment led to a better, i.e., longer, inhibitory effect on Alternaria padwickii, Rhizoctonia solani, Curvularia sp., Aspergillus flavus and Aspergillus niger than E+CL. Secondly, E+CL coating polymer showed the longest inhibitory effect against Bipolaris oryzae and Nigrospora oryzae compared to CA and CL coating polymer. Finally, both CA and E+CL coating polymer had non-significant difference inhibitory effect on Fusarium moniliforme. The variant of CL coating polymer for seed coating was only during the first 6 months of storage able to inhibit all species of the observed seed borne fungi, whereas CA and E+CL coating polymer were capable to inhibit most of the fungi until 9 months of storage.

  8. Hybrid Sterility in Rice (Oryza sativa L.) Involves the Tetratricopeptide Repeat Domain Containing Protein.

    Science.gov (United States)

    Yu, Yang; Zhao, Zhigang; Shi, Yanrong; Tian, Hua; Liu, Linglong; Bian, Xiaofeng; Xu, Yang; Zheng, Xiaoming; Gan, Lu; Shen, Yumin; Wang, Chaolong; Yu, Xiaowen; Wang, Chunming; Zhang, Xin; Guo, Xiuping; Wang, Jiulin; Ikehashi, Hiroshi; Jiang, Ling; Wan, Jianmin

    2016-07-01

    Intersubspecific hybrid sterility is a common form of reproductive isolation in rice (Oryza sativa L.), which significantly hampers the utilization of heterosis between indica and japonica varieties. Here, we elucidated the mechanism of S7, which specially causes Aus-japonica/indica hybrid female sterility, through cytological and genetic analysis, map-based cloning, and transformation experiments. Abnormal positioning of polar nuclei and smaller embryo sac were observed in F1 compared with male and female parents. Female gametes carrying S7(cp) and S7(i) were aborted in S7(ai)/S7(cp) and S7(ai)/S7(i), respectively, whereas they were normal in both N22 and Dular possessing a neutral allele, S7(n) S7 was fine mapped to a 139-kb region in the centromere region on chromosome 7, where the recombination was remarkably suppressed due to aggregation of retrotransposons. Among 16 putative open reading frames (ORFs) localized in the mapping region, ORF3 encoding a tetratricopeptide repeat domain containing protein was highly expressed in the pistil. Transformation experiments demonstrated that ORF3 is the candidate gene: downregulated expression of ORF3 restored spikelet fertility and eliminated absolutely preferential transmission of S7(ai) in heterozygote S7(ai)/S7(cp); sterility occurred in the transformants Cpslo17-S7(ai) Our results may provide implications for overcoming hybrid embryo sac sterility in intersubspecific hybrid rice and utilization of hybrid heterosis for cultivated rice improvement. Copyright © 2016 by the Genetics Society of America.

  9. Functions of the CCCH type zinc finger protein OsGZF1 in regulation of the seed storage protein GluB-1 from rice

    NARCIS (Netherlands)

    Chen, Y.; Sun, A.; Wang, M.; Zhu, Z.; Ouwerkerk, P.B.F.

    2014-01-01

    Glutelins are the most abundant storage proteins in rice grain and can make up to 80 % of total protein content. The promoter region of GluB-1, one of the glutelin genes in rice, has been intensively used as a model to understand regulation of seed-storage protein accumulation. In this study, we

  10. Chemical modification of a phenoxyfuranone-type strigolactone mimic for selective effects on rice tillering or Striga hermonthica seed germination.

    Science.gov (United States)

    Takahashi, Ikuo; Fukui, Kosuke; Asami, Tadao

    2016-11-01

    We previously reported that a series of phenoxyfuranone compounds, designated 'debranones', mimic strigolactone (SL) activity. 4-Bromodebranone (4BD) is a functionally selective SL mimic that reduces the number of shoot branches on rice more potently than GR24, a typical synthetic SL analogue, but does not induce seed germination in the root-parasitic plant Striga hermonthica. To enhance the selective activity of debranones in stimulating the seed germination of root-parasitic plants, we prepared several analogues of 4BD in which the chlorine atom was substituted with an H atom at the o-, m- or p-position on the phenyl ring (designated 2-, 3-, or 4-chlorodebranone, respectively) or had a bicyclic group instead of the phenyl ring. We evaluated the biological activities of the compounds with rice tillering assays and S. hermonthica seed germination assays. Both assays showed that the substituent position affected debranone efficiency, and among the monochlorodebranones, 2-chlorodebranone was more effective than the other two isomers in both assays. When the activities of the bicyclic debranones were compared in the same two assays, one was more active than GR24 in the rice tillering assay. This debranone also stimulated the germination of S. hermonthica seeds. Thus, some debranone derivatives induced the germination of S. hermonthica seeds, although their activities were still ∼1/20 that of GR24. These results strongly suggest that further and rigorous structure-activity relationship studies of the debranones will identify derivatives that more potently stimulate the suicidal germination of S. hermonthica seeds. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  11. Evidence for the Emergence of New Rice Types of Interspecific Hybrid Origin in West African Farmers' Fields

    NARCIS (Netherlands)

    Nuijten, H.A.C.P.; Treuren, van R.; Struik, P.C.; Mokuwa, G.A.; Okry, F.; Teeken, B.W.E.; Richards, P.

    2009-01-01

    In West Africa two rice species (Oryza glaberrima Steud. and Oryza sativa L.) co-exist. Although originally it was thought that interspecific hybridization is impossible without biotechnological methods, progenies of hybridization appear to occur in farmer fields. AFLP analysis was used to assess

  12. Effects of Pig Slurry as Basal and Panicle Fertilizer on Trace Element Content and Grain Quality in Direct-Seeding Rice

    Directory of Open Access Journals (Sweden)

    Lifen Huang

    2016-07-01

    Full Text Available Direct-seeding rice has grown in popularity in recent years and is widespread in China. This study focused on the effects of pig slurry (PS on grain quality and safety in direct-seeding rice. Application of more than 210 m3·hm−2 increased rice yield and dry matter accumulation, compared with conventional chemical fertilizer treatment (CK2. At the heading and maturing stage, a high dosage of PS (T6, T8 and T9 treatments promoted uptake of Pb, Cu, Zn, Fe and Mn by rice plants and grain, but retarded uptake of Cr, Co and Ni, indicating an ability to alleviate toxicity of some heavy metals. Compared with CK2, PS alleviated the transfer of Pb, Cr, Co, Ni and Cu from straw to grain, but enhanced the transport of Zn, Fe and Mn. Although PS application slightly diminished the processing quality, including brown rice, milled rice and head milled rice, it significantly decreased the amylose content, optimized the starch profile, and improved the overall quality. The results confirmed the feasibility and safety of PS application to direct-seeding rice, and determined that PS basal and panicle fertilizer could increase yield and improve the rice quality when applied between 210 and 240 m3·hm−2.

  13. Late nitrogen application enhances spikelet number in indica hybrid rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Wei Zhou

    Full Text Available ABSTRACT To increase rice yield potential, field experiments were conducted in farmers’ paddies in 2011 and 2012 to evaluate the effects of different nitrogen applications on the yield and panicle components of three typical indica hybrid rice varieties in Sichuan Province. The number of grains per panicle resulting from late nitrogen application (LA was 12 % greater than that obtained from traditional nitrogen application (TA; this increase was the main source of improvements in yield. The number of surviving and differentiated spikelets (NSS and NDiS resulting from LA was significantly higher than that measured under TA, especially for the Fyou498 cultivar, where the NSS and NDiS increased by 15 % and 14 %, respectively. Compared with TA, the number of degenerated secondary branches and the percentage of degenerated secondary branches (NDeSB and PDeSB were significantly reduced by 9 % and 11 %, respectively, by LA. This is the first study to demonstrate that an increase in NSS and a decrease in NDeSB lead to yield-improving effects attributable to LA. The grain yields of different varieties ranged from 9225.6 to 9408.7 kg ha−1, the PDeSB was as high as 31 %, and the number of surviving secondary branches (NSSB was significantly and positively correlated with NSS. These data indicate that the yield of indica hybrid rice has considerable potential for being improved, and increasing NSSB is key to increasing NSS and improving the grain yield. These improvements should be pursued so as to increase the yield of hybrid rice to ensure both food security and sustainable agricultural development.

  14. The effects of seed size on hybrids formed between oilseed rape (Brassica napus and wild brown mustard (B. juncea.

    Directory of Open Access Journals (Sweden)

    Yong-Bo Liu

    Full Text Available Seed size has significant implications in ecology, because of its effects on plant fitness. The hybrid seeds that result from crosses between crops and their wild relatives are often small, and the consequences of this have been poorly investigated. Here we report on plant performance of hybrid and its parental transgenic oilseed rape (Brassica napus and wild B. juncea, all grown from seeds sorted into three seed-size categories.Three seed-size categories were sorted by seed diameter for transgenic B. napus, wild B. juncea and their transgenic and non-transgenic hybrids. The seeds were sown in a field at various plant densities. Globally, small-seeded plants had delayed flowering, lower biomass, fewer flowers and seeds, and a lower thousand-seed weight. The seed-size effect varied among plant types but was not affected by plant density. There was no negative effect of seed size in hybrids, but it was correlated with reduced growth for both parents.Our results imply that the risk of further gene flow would probably not be mitigated by the small size of transgenic hybrid seeds. No fitness cost was detected to be associated with the Bt-transgene in this study.

  15. Effect of hybrid, storage conditions and seed protection on sunflower field emergence

    Directory of Open Access Journals (Sweden)

    Mrđa Jelena

    2010-01-01

    Full Text Available Seed emergence under field conditions decisively and directly determines the number of plants per hectare, which is one of three basic components of yield in the plant world. Influence of chemical treatment on field emergence of three commercial sunflower hybrids stored in different conditions was tested in 2007 and 2008 on experimental field of Institute of Field and Vegetable Crops in Novi Sad. On average, hybrid H1 had the highest value of field emergence (88.79% and for chemical treatment fl udioxonil + metalaxyl + imidacloprid (87.71%. Seed kept in common storage had the highest emergence value in fi eld (87.92%. Seed treated with fl udioxonil + metalaxyl + imidacloprid and stored for one year in common storage had the highest field emergence (90.18%. Considering interaction between storage conditions and genotype, hybrid H1 seed sown after chemical treatment had the highest field emergence (91.82% and seed kept in common storage (90.48%. Hybrid H1 seed compared with other two had the highest field emergence treated with fludioxonil + metalaxyl + imidacloprid (91.84%.

  16. Genetic and Physiological Characterization of Two Clusters of Quantitative Trait Loci Associated With Seed Dormancy and Plant Height in Rice

    OpenAIRE

    Ye, Heng; Beighley, Donn H.; Feng, Jiuhuan; Gu, Xing-You

    2013-01-01

    Seed dormancy and plant height have been well-studied in plant genetics, but their relatedness and shared regulatory mechanisms in natural variants remain unclear. The introgression of chromosomal segments from weedy into cultivated rice (Oryza sativa) prompted the detection of two clusters (qSD1-2/qPH1 and qSD7-2/qPH7) of quantitative trait loci both associated with seed dormancy and plant height. Together, these two clusters accounted for >96% of the variances for plant height and ~71% of t...

  17. Characterization and Ectopic Expression of CoWRI1, an AP2/EREBP Domain-Containing Transcription Factor from Coconut (Cocos nucifera L.) Endosperm, Changes the Seeds Oil Content in Transgenic Arabidopsis thaliana and Rice (Oryza sativa L.).

    Science.gov (United States)

    Sun, RuHao; Ye, Rongjian; Gao, Lingchao; Zhang, Lin; Wang, Rui; Mao, Ting; Zheng, Yusheng; Li, Dongdong; Lin, Yongjun

    2017-01-01

    Coconut ( Cocos nucifera L.) is a key tropical crop and a member of the monocotyledonous family Arecaceae ( Palmaceae ). Few genes and related metabolic processes involved in coconut endosperm development have been investigated. In this study, a new member of the WRI1 gene family was isolated from coconut endosperm and was named CoWRI1 . Its transcriptional activities and interactions with the acetyl-CoA carboxylase ( BCCP2 ) promoter of CoWRI1 were confirmed by the yeast two-hybrid and yeast one-hybrid approaches, respectively. Functional characterization was carried out through seed-specific expression in Arabidopsis and endosperm-specific expression in rice. In transgenic Arabidopsis , high over-expressions of CoWRI1 in seven independent T2 lines were detected by quantitative real-time PCR. The relative mRNA accumulation of genes encoding enzymes involved in either fatty acid biosynthesis or triacylglycerols assembly (BCCP2, KASI, MAT, ENR, FATA, and GPDH) were also assayed in mature seeds. Furthermore, lipid and fatty acids C16:0 and C18:0 significantly increased. In two homozygous T2 transgenic rice lines (G5 and G2), different CoWRI1 expression levels were detected, but no CoWRI1 transcripts were detected in the wild type. Analyses of the seed oil content, starch content, and total protein content indicated that the two T2 transgenic lines showed a significant increase ( P oil content. The transgenic lines also showed a significant increase in starch content, whereas total protein content decreased significantly. Further analysis of the fatty acid composition revealed that palmitic acid (C16:0) and linolenic acid (C18:3) increased significantly in the seeds of the transgenic rice lines, but oleic acid (C18:1) levels significantly declined.

  18. Genomic structural variation-mediated allelic suppression causes hybrid male sterility in rice.

    Science.gov (United States)

    Shen, Rongxin; Wang, Lan; Liu, Xupeng; Wu, Jiang; Jin, Weiwei; Zhao, Xiucai; Xie, Xianrong; Zhu, Qinlong; Tang, Huiwu; Li, Qing; Chen, Letian; Liu, Yao-Guang

    2017-11-03

    Hybrids between divergent populations commonly show hybrid sterility; this reproductive barrier hinders hybrid breeding of the japonica and indica rice (Oryza sativa L.) subspecies. Here we show that structural changes and copy number variation at the Sc locus confer japonica-indica hybrid male sterility. The japonica allele, Sc-j, contains a pollen-essential gene encoding a DUF1618-domain protein; the indica allele, Sc-i, contains two or three tandem-duplicated ~ 28-kb segments, each carrying an Sc-j-homolog with a distinct promoter. In Sc-j/Sc-i hybrids, the high-expression of Sc-i in sporophytic cells causes suppression of Sc-j expression in pollen and selective abortion of Sc-j-pollen, leading to transmission ratio distortion. Knocking out one or two of the three Sc-i copies by CRISPR/Cas9 rescues Sc-j expression and male fertility. Our results reveal the gene dosage-dependent allelic suppression as a mechanism of hybrid incompatibility, and provide an effective approach to overcome the reproductive barrier for hybrid breeding.

  19. Improving hybrid seed production in corn with glyphosate-mediated male sterility.

    Science.gov (United States)

    Feng, Paul C C; Qi, Youlin; Chiu, Tommy; Stoecker, Martin A; Schuster, Christopher L; Johnson, Scott C; Fonseca, Augustine E; Huang, Jintai

    2014-02-01

    Hybrid corn varieties exhibit benefits associated with heterosis and account for most of the corn acreage in the USA. Hybrid seed corn is produced by crossing a female parent which is male-sterile and therefore incapable of self-pollination with a male parent as the pollen donor. The majority of hybrid seed corn is produced by mechanical detasseling which involves physically removing the tassel, a process that is laborious and costly. Glyphosate-resistant corn was developed via expression of a glyphosate insensitive 5-enolpyruvyl-shikimate 3-phosphate synthase enzyme (CP4-EPSPS). Experimentation with molecular expression elements resulted in selective reduction of CP4-EPSPS expression in male reproductive tissues. The resulting plant demonstrated sterile tassel following glyphosate application with little to no injury to the rest of the plant. Using (14)C-glyphosate as a marker, we also examined the translocation of glyphosate to the tassel via spray application in a track sprayer to simulate field application. The results allowed optimization of spray parameters such as dose, spray timing and target to maximize tassel delivery of glyphosate for efficient sterilization. The Roundup hybridization system (RHS) is a novel process for hybrid seed production based on glyphosate-mediated male sterility. RHS replaces mechanical detasseling with glyphosate spray and greatly simplifies the process of hybrid seed corn production. © 2013 Society of Chemical Industry.

  20. Effect of combined treatments of neutron radiation and plant growth regulator (GA) on seed germination and growth of rice

    International Nuclear Information System (INIS)

    Xie Chonghua; Wang Dan; Chen Yongjun; Wang Ying; Luo Jie; Liao Wei; Zheng Chun

    2007-01-01

    Rice seeds were irradiated with fast-neutron impulse pile and then were treated with different concentration of GA 3 . The effect of combined treatments on seeds germination and seedling growth were studied. The results showed that lethal pouring dose of neutron radiation on Hongai B and CB was 486 x 10 10 /cm 2 , Mianhui 2009 was 900 x 10 10 /cm 2 and Mianhui 2095 and Minghui 63 were 1350 x 10 10 /cm 2 . Semi-lethal pouring dose (LD 50 ) of neutron radiation on Hongai Band CB was 198-486 x 10 10 /cm 2 , Mianhui 2009 was about 486 x 10 10 /cm 2 , Minghui 63 was 629.49 x 10 10 /cm 2 and Mianhui 2095 is 774.69 x 10 10 /cm 2 . Radiation sensitivity of rice is Hongai B, CB>Mianhui 2009>Minghui 63>Mianhui 2095. GA 3 is a kind of efficient chemical radiation protection. 40 and 80 mg/L are the proper GA 3 concentrations of neutron irradiated rice seeds. (authors)

  1. Physiological effects of endogenous IAA on grain filling of hybrid rice Xieyou 9308

    International Nuclear Information System (INIS)

    Tao Longxing; Wang Xi; Zhang Fudao

    2003-01-01

    The progress of grain filling and effects of TIBA and PCIB on sugar content and IAA level in superior and inferior spikelets of hybrid rice Xieyou 9308 and its restorer R-9308 were studied. The grain weight increment rate and sugar (fructose, glucose and sucrose) in superior spikelets were higher than those in inferior spikelets until 7 days after pollination, then, they were higher in inferior spikelets than those in superior ones. The differences of physiological activities between superior and inferior spikelets were more significant in combinations than in their restorers. IAA inhibitors decreased 3 H-IAA and 3 H-Try contents in both superior and inferior spikelets, reduced the efficiency of 3 H-Try bio-transforming to 3 H-IAA in rice plant and, therefor, reduced 3 H-glucose in grain. By treatment with high concentration of exogenous IAA on young panicle before heading, the grain-setting difference between superior and inferior spikelets was significantly decreased, and the total grain setting rate increased, indicating that IAA impels the grain filling progress in hybrid rice

  2. Seed quality and water use characteristics of maize landraces compared with selected commercial hybrids

    Directory of Open Access Journals (Sweden)

    Farai Mazvimbakupa

    2015-03-01

    Full Text Available Understanding seed quality and water use characteristics of maize (Zea mays L. landraces will improve food security among subsistence farmers who still cultivate them. The objective of this study was to evaluate seed quality and water use characteristics of two maize landraces (GQ1 and GQ2 compared with two commercial hybrids (SC701 and PAN53. Seed quality was determined by the standard germination, electrical conductivity, and tetrazolium tests. A controlled environment study was conducted in which the landraces were compared with hybrids across three water treatments (30% ETc; 50% ETc, and 80% ETc. Although landrace GQ2 performed at par with the hybrids, overall, seed quality tests showed that hybrids had superior seed quality than landraces. This was also confirmed by highly significant emergence results (P < 0.001 from pot trials where SC701 and PAN53 had higher emergence (100% and 94.44%, respectively compared with GQ2 (86.11% and GQ1 (61.11%. Subjecting landraces and hybrids to water stress (50% and 30% ETc resulted in shorter plants with fewer leaves and earlier tasselling compared with non-stressed plants (80% ETc. Plant height for the 30% ETc water treatment was 156.1 cm compared with 175.8 cm for the 80% ETc water treatment, while plants under the 30% ETc water treatment tasseled at 105.4 d compared with 129.5 d for the 80% ETc water treatment. The GQ2 landrace continued to perform similar to, and often better, than the hybrid varieties, especially under stress conditions. Yield was poor under controlled conditions. Performance of the GQ2 landrace for both seed quality tests and under controlled conditions shows that landraces remain an important germplasm resource.

  3. CORRELATION BETWEEN SEED TESTS AND FIELD EMERGENCE OF TWO MAIZE HYBRIDS (SC704 AND SC500)

    OpenAIRE

    A.A. ALILOO; B. SHOKATI

    2011-01-01

    Early emergence and stand establishment of maize (Zea mays L.) are considered to be the most important yield-contributing factors. The influence of seed vigor on these factors is vital. Therefore, five laboratory tests and field experiment were conducted on basis of a randomized complete block design (RCBD) with five replications in 2011, to evaluate the correlation among the seed vigor tests and field emergence of two maize hybrids (SC704 and SC500). In laboratory tests, differences between ...

  4. Low hybrid onion seed yields relate to honey bee visits and insecticide use

    OpenAIRE

    Long, Rachael Freeman; Morandin, Lora

    2011-01-01

    Onion thrips, previously considered of minor importance to hybrid onion seed production in California, vector the newly introduced iris yellow spot virus, a serious pathogen of onions that can cause significant yield losses. Insecticide use to control onion thrips has increased in onion seed fields, coincident with a steep decrease in yields, especially in Colusa County. We examined a number of possible contributing factors and found a strong positive correlation between honey bee activity an...

  5. The effectiveness of preplant seed bio-invigoration techniques using Bacillus sp. CKD061 to improving seed viability and vigor of several local upland rice cultivars of Southeast Sulawesi

    Science.gov (United States)

    Sutariati, G. A. K.; Bande, L. O. S.; Khaeruni, A.; Muhidin; Mudi, L.; Savitri, R. M.

    2018-02-01

    Research was aimed to evaluate the bio-invigoration techniques using Bacillus sp. CKD061 in improving seed viability and vigor of local upland rice. The research is arranged in factorial with completely randomized design (CRD). The different upland rice cultivars as first factor that consists of 11 cultivars, namely: Pae Tinangge, Pae Rowu, Pae Uwa, Pae Tanta, Pae Waburi-Buri, Pae Mornene, Pae Indalibana, Pae Lawarangka, Pae Huko, Pae Wagamba and Pae Momea. The second factor is the seed bio-invigoration technique, consists of 5 treatments, namely: without seed bio-invigoration (B0), NaCl + Bacillus sp. CKD061 (B1), KNO3 + Bacillus sp. CKD061 (B2), Ground burned-rice husk + Bacillus sp. CKD061 (B3), and Ground brick + Bacillus sp. CKD061 (B4). The results showed that seed bio-invigoration using Bacillus sp. CKD061 gave effect on the seed viability and vigor. Interaction of the seed bio-invigoration and upland rice cultivars were able to improve seed viability and vigor. Seed bio-invigoration ttreatment using ground brick + Bacillus sp. CKD061 was the best treatment, which could improve the viability and vigor of Pae Waburi-Buri, Pae Mornene and Pae Indalibana. The treatment increased vigor index by 133% in Pae Waburi-Buri and 127% in Pae Mornene, and Pae Indalibana compared with control.

  6. Seedling development and evaluation of genetic stability of cryopreserved Dendrobium hybrid mature seeds.

    Science.gov (United States)

    Galdiano, Renato Fernandes; de Macedo Lemos, Eliana Gertrudes; de Faria, Ricardo Tadeu; Vendrame, Wagner Aparecido

    2014-03-01

    Vitrification, a simple, fast, and recommended cryopreservation method for orchid germplasm conservation, was evaluated for Dendrobium hybrid "Dong Yai" mature seeds. The genetic stability of regenerated seedlings was also evaluated using flow cytometry. Mature seeds from this hybrid were submitted to plant vitrification solution (PVS2) for 0, 0.5, 1, 2, 3, 4, 5, or 6 h at 0 °C. Subsequently, they were plunged into liquid nitrogen (LN) at -196 °C for 1 h and recovered in half-strength Murashige and Skoog culture medium (1/2 MS), and seed germination was evaluated after 30 days. Seeds directly submitted to LN did not germinate after cryopreservation. Seeds treated with PVS2 between 1 and 3 h presented the best germination (between 51 and 58%), although longer exposure to PVS2 returned moderated germination (39%). Germinated seeds were further subcultured in P-723 culture medium and developed whole seedlings in vitro after 180 days, with no abnormal characteristics, diseases, or nutritional deficiencies. Seedlings were successfully acclimatized under greenhouse conditions with over 80% survival. Flow cytometry analysis revealed no chromosomal changes on vitrified seedlings, as well as seedlings germinated from the control treatment (direct exposure to LN). These findings indicate that vitrification is a feasible and safe germplasm cryopreservation method for commercial Dendrobium orchid hybrid conservation.

  7. Onion Hybrid Seed Production: Relation with Nectar Composition and Flower Traits.

    Science.gov (United States)

    Soto, Veronica C; Caselles, Cristian A; Silva, Maria F; Galmarini, Claudio R

    2018-05-28

    Onion (Allium cepa L.) is one of the main vegetable crops. Pollinators are required for onion seed production, being honeybees the most used. Around the world, two types of onion varieties are grown: open pollinated (OP) and hybrids. Hybrids offer numerous advantages to growers, but usually have lower seed yields than OP cultivars, which in many cases compromise the success of new hybrids. As pollination is critical for seed set, understanding the role of floral rewards and attractants to pollinator species is the key to improve crop seed yield. In this study, the correlation of nectar-analyzed compounds, floral traits, and seed yield under open field conditions in two experimental sites was determined. Nectar composition was described through the analysis of sugars, phenol, and alkaloid compounds. Length and width of the style and tepals of the flowers were measured to describe floral traits. Floral and nectar traits showed differences among the studied lines. For nectar traits, we found a significant influence of the environment where plants were cultivated. Nonetheless, flower traits were not influenced by the experimental sites. The OP and the male-sterile lines (MSLs) showed differences in nectar chemical composition and floral traits. In addition, there were differences between and within MSLs, some of which were correlated with seed yield, bringing the opportunity to select the most productive MSL, using simple determinations of morphological characters like the length of the style or tepals size.

  8. Performance of Different Herbicides in Dry-Seeded Rice in Bangladesh

    Science.gov (United States)

    Ahmed, Sharif; Chauhan, Bhagirath Singh

    2014-01-01

    A field study was conducted in the boro season of 2011-12 and aman season of 2012 at Jessore, Bangladesh, to evaluate the performance of sequential applications of preemergence herbicides (oxadiargyl 80 g ai ha−1, pendimethalin 850 g ai ha−1, acetachlor + bensulfuranmethyl 240 g ai ha−1, and pyrazosulfuron 15 g ai ha−1) followed by a postemergence herbicide (ethoxysulfuron 18 g ai ha−1) in dry-seeded rice. All evaluated herbicides reduced weed density and biomass by a significant amount. Among herbicides, pendimethalin, oxadiargyl, and acetachlor + bensulfuranmethyl performed very well against grasses; pyrazosulfuron, on the other hand, was not effective. The best herbicide for broadleaf weed control was oxadiargyl (65–85% control); pendimethalin and acetachlor + bensulfuraonmethyl were not effective for this purpose. The best combination for weed control was oxadiargyl followed by ethoxysulfuron in the boro season and oxadiargyl followed by a one-time hand weeding in the aman season. Compared with the partial weedy plots (hand weeded once), oxadiargyl followed by ethoxysulfuron (4.13 t ha−1) provided a 62% higher yield in the boro season while oxadiargyl followed by a one-time hand weeding (4.08 t ha−1) provided a 37% higher yield in the aman season. PMID:24688423

  9. Vacuolar processing enzyme plays an essential role in the crystalline structure of glutelin in rice seed.

    Science.gov (United States)

    Kumamaru, Toshihiro; Uemura, Yuji; Inoue, Yoshimi; Takemoto, Yoko; Siddiqui, Sadar Uddin; Ogawa, Masahiro; Hara-Nishimura, Ikuko; Satoh, Hikaru

    2010-01-01

    To identify the function of genes that regulate the processing of proglutelin, we performed an analysis of glup3 mutants, which accumulates excess amounts of proglutelin and lack the vacuolar processing enzyme (VPE). VPE activity in developing seeds from glup3 lines was reduced remarkably compared with the wild type. DNA sequencing of the VPE gene in glup3 mutants revealed either amino acid substitutions or the appearance of a stop codon within the coding region. Microscopic observations showed that alpha-globulin and proglutelin were distributed homogeneously within glup3 protein storage vacuoles (PSVs), and that glup3 PSVs lacked the crystalline lattice structure typical of wild-type PSVs. This suggests that the processing of proglutelin by VPE in rice is essential for proper PSV structure and compartmentalization of storage proteins. Growth retardation in glup3 seedlings was also observed, indicating that the processing of proglutelin influences early seedling development. These findings indicate that storage of glutelin in its mature form as a crystalline structure in PSVs is required for the rapid use of glutelin as a source of amino acids during early seedling development. In conclusion, VPE plays an important role in the formation of protein crystalline structures in PSVs.

  10. Gene, protein, and network of male sterility in rice

    OpenAIRE

    Wang, Kun; Peng, Xiaojue; Ji, Yanxiao; Yang, Pingfang; Zhu, Yingguo; Li, Shaoqing

    2013-01-01

    Rice is one of the most important model crop plants whose heterosis has been well-exploited in commercial hybrid seed production via a variety of types of male-sterile lines. Hybrid rice cultivation area is steadily expanding around the world, especially in Southern Asia. Characterization of genes and proteins related to male sterility aims to understand how and why the male sterility occurs, and which proteins are the key players for microspores abortion. Recently, a series of genes and prot...

  11. Production, Marketing and Value Chain Mapping of 'Srijana' Tomato Hybrid Seed in Nepal

    Directory of Open Access Journals (Sweden)

    Dinesh Babu Thapa Magar

    2016-12-01

    Full Text Available A tomato variety known as ‘Srijana’ developed by Nepal Agricultural Research Council (NARC has been substantially popular among Nepalese farmers and entrepreneurs. To understand the seed value chain of the Srijana hybrid tomato, a survey was conducted in 2014/15 with public research and extension institutions, private seed companies/firms, non-governmental organization and community group including individual farmers, involved in Srijana tomato seed production. The survey covered random selection of 30 agro-vets and 30 farmers in Kathmandu valley, Kavre, Nuwakot, Dolakha and Kaski districts, Nepal where production of Srijana tomato seed is mostly concentrated. A focus group discussion was also conducted with commercial tomato farmers in each of the study districts. The study showed a total production of 293 kg Srijana seed having a value of around 47 million Nepalese Rupees (US $ 470 thousands in year 2013/14. Private sector was the dominant actor sharing about 85% of the total Srijana seed production followed by non-governmental organization (10%, farmers group (3% and governmental station/farm/centers (2%, respectively. Out of the total Srijana seed produced, about 95% was consumed in domestic market while 5% was exported to India. The study revealed increasing trend of production, supply and price of Srijana tomato seed. About 0.3 million NRs (US $ 3,000 profit was estimated through the production of Srijana tomato seed in 0.05 hectares (500 m2 of land. Agro-vets (private sector seed dealers were the major actors for supplying the seed from the producers to farms and received a higher profit margins. The farmers producing and selling the seed in technical assistance of public agencies received higher producer`s share (66.6% than farmers producing and selling seed through own group (60%, technical assistance of non-governmental organization (53.3%, and in contract with private seed companies (26.7%. Majority of commercial tomato farmers

  12. Virulence Types of Magnaporthe oryzae to Hybrid Rice in Sichuan, China

    Directory of Open Access Journals (Sweden)

    Yu-lian BAI

    2012-12-01

    Full Text Available A total of 638 isolates of rice blast (Magnaporthe oryzae were isolated in 2002–2009 from different rice varieties in different regions of Sichuan, China and inoculated onto seven rice varieties (Lijiangxintuanheigu, IR24, Minghui 63, Duohui 1, Chenghui 448, Neihui 99-14 and RHR-1 to differentiate the virulence types of the fungus and trace the changes. The virulence to the seven varieties was respectively scored at 1, 2, 4, 8, 16, 32 and 64. The total scores of individual M. grisea isolates which were the sum of scores infecting differential varieties could, in turn, be used for the nomenclature of the virulence types due to their accordance to the special virulence patterns. The 638 tested isolates were then differentiated into 56 different virulence types. Type 15 virulent to Lijiangxintuanheigu, IR24 and Minghui 63, and Type 127 virulent to all of the seven varieties were the most dominant virulence types respectively with the occurrence frequencies of 15.99% and 15.83%. Type 19 and other seven virulence types were not monitored during 2002–2009. Type 15 was the predominant virulence type in 2002, 2003, 2004 and 2007, whereas Type 127 had been the most dominant virulence type after 2005 except for the year 2007 when the province underwent severe drought. Five hundred and seven out of the 638 tested isolates were virulent to Minghui 63, and 89.58% of the 384 isolates virulent to either Duohui 1, Chenghui 448 or Neihui 99-14 were virulent to Minghui 63, which indicated the impact of the extensive plantation of hybrid rice Minghui 63 as the restorer line on the virulence evolution of M. oryzae in Sichuan. The virulence pattern of the dominant virulence types suggested that the acquiring of virulence to all the major resistant restorer lines was the main routes of the evolution in virulence of M. oryzae to hybrid rice in Sichuan. The virulence frequencies of the 638 tested isolates to IR24, Minghui 63, Duohui 1, Chenghui 448, Neihui 99

  13. Insecticide use in hybrid onion seed production affects pre- and postpollination processes.

    Science.gov (United States)

    Gillespie, Sandra; Long, Rachael; Seitz, Nicola; Williams, Neal

    2014-02-01

    Research on threats to pollination service in agro-ecosystems has focused primarily on the negative impacts of land use change and agricultural practices such as insecticide use on pollinator populations. Insecticide use could also affect the pollination process, through nonlethal impacts on pollinator attraction and postpollination processes such as pollen viability or pollen tube growth. Hybrid onion seed (Allium cepa L., Alliaceae) is an important pollinator-dependent crop that has suffered yield declines in California, concurrent with increased insecticide use. Field studies suggest that insecticide use reduces pollination service in this system. We conducted a field experiment manipulating insecticide use to examine the impacts of insecticides on 1) pollinator attraction, 2) pollen/stigma interactions, and 3) seed set and seed quality. Select insecticides had negative impacts on pollinator attraction and pollen/stigma interactions, with certain products dramatically reducing pollen germination and pollen tube growth. Decreased pollen germination was not associated with reduced seed set; however, reduced pollinator attraction was associated with lower seed set and seed quality, for one of the two female lines examined. Our results highlight the importance of pesticide effects on the pollination process. Overuse may lead to yield reductions through impacts on pollinator behavior and postpollination processes. Overall, in hybrid onion seed production, moderation in insecticide use is advised when controlling onion thrips, Thrips tabaci, on commercial fields.

  14. EFFECT OF DIFFERENT INSECTICIDES UPON GERMINATION AND VIGOR OF RICE SEEDS EFEITO DE DIFERENTES INSETICIDAS NA GERMINAÇÃO E NO VIGOR DE SEMENTES DE ARROZ

    OpenAIRE

    Antônio Lopes da Silva; Valquíria da Rocha Santos Veloso; Noga Neve Ribeiro Guimarães

    2007-01-01

    A laboratory test was conducted, aiming to verify the effect of different insecticides upon germinating power and vigor of rice seeds, cultivars IAC - 25 and Rio-Paranaíba, stored at 0, 7,15, 30, 60 and 90 days, after treatments. Germination tests were settled according routine analysis and evaluated after seven days by counting number of normal and abnormal plantules and dead seeds. For vigor test, the seeds were ...

  15. An Integrated “Multi-Omics” Comparison of Embryo and Endosperm Tissue-Specific Features and Their Impact on Rice Seed Quality

    Directory of Open Access Journals (Sweden)

    Marc Galland

    2017-11-01

    Full Text Available Although rice is a key crop species, few studies have addressed both rice seed physiological and nutritional quality, especially at the tissue level. In this study, an exhaustive “multi-omics” dataset on the mature rice seed was obtained by combining transcriptomics, label-free shotgun proteomics and metabolomics from embryo and endosperm, independently. These high-throughput analyses provide a new insight on the tissue-specificity related to rice seed quality. Foremost, we pinpointed that extensive post-transcriptional regulations occur at the end of rice seed development such that the embryo proteome becomes much more diversified than the endosperm proteome. Secondly, we observed that survival in the dry state in each seed compartment depends on contrasted metabolic and enzymatic apparatus in the embryo and the endosperm, respectively. Thirdly, it was remarkable to identify two different sets of starch biosynthesis enzymes as well as seed storage proteins (glutelins in both embryo and endosperm consistently with the supernumerary embryo hypothesis origin of the endosperm. The presence of a putative new glutelin with a possible embryonic favored abundance is described here for the first time. Finally, we quantified the rate of mRNA translation into proteins. Consistently, the embryonic panel of protein translation initiation factors is much more diverse than that of the endosperm. This work emphasizes the value of tissue-specificity-centered “multi-omics” study in the seed to highlight new features even from well-characterized pathways. It paves the way for future studies of critical genetic determinants of rice seed physiological and nutritional quality.

  16. Influence of Crop Nutrition on Grain Yield, Seed Quality and Water Productivity under Two Rice Cultivation Systems

    Directory of Open Access Journals (Sweden)

    Y.V. SINGH

    2013-03-01

    Full Text Available The system of rice intensification (SRI is reported to have advantages like lower seed requirement, less pest attack, shorter crop duration, higher water use efficiency and the ability to withstand higher degree of moisture stress than traditional method of rice cultivation. With this background, SRI was compared with traditional transplanting technique at Indian Agricultural Research Institute, New Delhi, India during two wet seasons (2009–2011. In the experiment laid out in a factorial randomized block design, two methods of rice cultivation [conventional transplanting (CT and SRI] and two rice varieties (Pusa Basmati 1 and Pusa 44 were used under seven crop nutrition treatments, viz. T1, 120 kg/hm2 N, 26.2 kg/hm2 P and 33 kg/hm2 K; T2, 20 t/hm2 farmyard manure (FYM; T3, 10 t/hm2 FYM + 60 kg/hm2 N; T4, 5 t/hm2 FYM + 90 kg/hm2 N; T5, 5 t/hm2 FYM + 60 kg/hm2 N + 1.5 kg/hm2 blue green algae (BGA; T6, 5 t/hm2 FYM + 60 kg/hm2 N + 1.0 t/hm2 Azolla, and T7, N0P0K0 (control, no NPK application to study the effect on seed quality, yield and water use. In SRI, soil was kept at saturated moisture condition throughout vegetative phase and thin layer of water (2–3 cm was maintained during the reproductive phase of rice, however, in CT, standing water was maintained in crop growing season. Results revealed that CT and SRI gave statistically at par grain yield but straw yield was significantly higher in CT as compared to SRI. Seed quality was superior in SRI as compared to CT. Integrated nutrient management (INM resulted in higher plant height with longer leaves than chemical fertilizer alone in both the rice varieties. Grain yield attributes such as number of effective tillers per hill, panicle length and panicle weight of rice in both the varieties were significantly higher in INM as compared to chemical fertilizer alone. Grain yields of both the varieties were the highest in INM followed by the recommended doses of chemical fertilizer. The grain yield

  17. Split-gene system for hybrid wheat seed production.

    Science.gov (United States)

    Kempe, Katja; Rubtsova, Myroslava; Gils, Mario

    2014-06-24

    Hybrid wheat plants are superior in yield and growth characteristics compared with their homozygous parents. The commercial production of wheat hybrids is difficult because of the inbreeding nature of wheat and the lack of a practical fertility control that enforces outcrossing. We describe a hybrid wheat system that relies on the expression of a phytotoxic barnase and provides for male sterility. The barnase coding information is divided and distributed at two loci that are located on allelic positions of the host chromosome and are therefore "linked in repulsion." Functional complementation of the loci is achieved through coexpression of the barnase fragments and intein-mediated ligation of the barnase protein fragments. This system allows for growth and maintenance of male-sterile female crossing partners, whereas the hybrids are fertile. The technology does not require fertility restorers and is based solely on the genetic modification of the female crossing partner.

  18. Seed longevity of red rice ecotypes buried in soil Longevidade de sementes de arroz-vermelho enterradas no solo

    Directory of Open Access Journals (Sweden)

    J.A. Noldin

    2006-12-01

    Full Text Available Red rice is a troublesome weed in irrigated rice production and is spread through contaminated commercial rice seed and machinery. Seed dormancy is a major trait for red rice. Studies were carried out at two locations to determine red rice seed longevity in the soil of several ecotypes from four US states. Five months after burial near Beaumont, Texas only three ecotypes had viable seed (O arroz-vermelho constitui-se na principal planta daninha infestante de lavouras de arroz irrigado e a sua disseminação ocorre, principalmente, pelo uso de sementes comerciais contaminadas e equipamentos agrícolas. A ocorrência de dormência nas sementes é uma das principais características que dificultam o controle do arroz-vermelho em lavouras. O objetivo deste trabalho foi estimar a longevidade no solo de ecótipos de arroz-vermelho provenientes de diferentes áreas de produção de arroz nos Estados Unidos. O estudo foi conduzido em dois locais: Beaumont e College Station, no estado do Texas (TX. Para sementes enterradas a 5 cm de profundidade em Beaumont, apenas três ecótipos apresentaram sementes viáveis (<1%. No entanto, quando as sementes foram enterradas em maior profundidade (25 cm, nove ecótipos tinham sementes viáveis após 2 anos. Trinta e seis meses após o enterrio, cinco ecótipos apresentavam sementes com alguma viabilidade, mas todos inferiores a 1%. Sementes de arroz-vermelho produzidas e enterradas em College Station na profundidade de 12 cm, um dia após a colheita, apresentaram maior longevidade que aquelas mantidas na superfície do solo. Após 17 meses, um dos ecótipos de arroz-preto (TX 4, enterrado a 12 cm, foi o que apresentou maior percentual de viabilidade (2%. Nos dois experimentos, observou-se que os cultivares comerciais, Lemont e Mars, não apresentaram sementes viáveis após cinco meses, independentemente da localização no solo. Os resultados deste estudo sugerem que em áreas com arroz-vermelho deve-se evitar o

  19. Immediate Genetic and Epigenetic Changes in F1 Hybrids Parented by Species with Divergent Genomes in the Rice Genus (Oryza.

    Directory of Open Access Journals (Sweden)

    Ying Wu

    Full Text Available Inter-specific hybridization occurs frequently in higher plants, and represents a driving force of evolution and speciation. Inter-specific hybridization often induces genetic and epigenetic instabilities in the resultant homoploid hybrids or allopolyploids, a phenomenon known as genome shock. Although genetic and epigenetic consequences of hybridizations between rice subspecies (e.g., japonica and indica and closely related species sharing the same AA genome have been extensively investigated, those of inter-specific hybridizations between more remote species with different genomes in the rice genus, Oryza, remain largely unknown.We investigated the immediate chromosomal and molecular genetic/epigenetic instability of three triploid F1 hybrids produced by inter-specific crossing between species with divergent genomes of Oryza by genomic in situ hybridization (GISH and molecular marker analysis. Transcriptional and transpositional activity of several transposable elements (TEs and methylation stability of their flanking regions were also assessed. We made the following principle findings: (i all three triploid hybrids are stable in both chromosome number and gross structure; (ii stochastic changes in both DNA sequence and methylation occurred in individual plants of all three triploid hybrids, but in general methylation changes occurred at lower frequencies than genetic changes; (iii alteration in DNA methylation occurred to a greater extent in genomic loci flanking potentially active TEs than in randomly sampled loci; (iv transcriptional activation of several TEs commonly occurred in all three hybrids but transpositional events were detected in a genetic context-dependent manner.Artificially constructed inter-specific hybrids of remotely related species with divergent genomes in genus Oryza are chromosomally stable but show immediate and highly stochastic genetic and epigenetic instabilities at the molecular level. These novel hybrids might

  20. Produção de sementes macho-estéreis em arroz Male-sterile rice seed production

    Directory of Open Access Journals (Sweden)

    Claudio Bragantini

    2001-02-01

    Full Text Available A obtenção comercial de sementes da linhagem macho-estéril é uma das limitações para viabilizar a produção de híbridos de arroz (Oryza sativa L.. Este trabalho buscou estudar três proporções entre a linhagem macho-estéril (linhagem A e a mantenedora (linhagem B. As proporções estudadas foram 8:4, 10:2 e 14:4. As características avaliadas para determinar qual das proporções apresenta maior potencial foram: número e porcentagem de grãos cheios por panículas, e número de grãos de pólen por unidade de área. A proporção 8:4 produziu maior porcentagem de grãos cheios por panícula que as outras duas, mas, proporcionalmente, ocupa maior área física com a linhagem B no campo. Foram observadas diferenças estatísticas na porcentagem de grãos cheios entre as amostras coletadas nas várias fileiras da linhagem A (diferentes distâncias da fonte polinizadora, e observou-se uma influência marcante com relação à direção predominante dos ventos. O número de grãos de pólen foi igual para todas as relações e distâncias da fonte de pólen; por isso, não foi o fator determinante das diferenças observadas em porcentagem de grãos cheios por panícula. Os resultados permitiram concluir que a proporção 10:2 é a de maior potencial para a produção comercial de sementes da linhagem macho-estéril.Commercial male-sterile rice (Oryza sativa L. seed production is one of the limitations to allow large scale hybrid seed production. This work studied three ratios between male-sterile line (A line and maintainer (B line. The A:B ratios used in the study were: 8:4, 10:2 and 14:4. The evaluated traits to determine which ratio is more suitable were: number and percentage of filled grains per panicle and number of pollen grains per unit area. The 8:4 ratio produced statistically significant higher percentage of filled grains per panicle than the other two, but proportionally it requires more field area for the B line. Statistical

  1. Response of S.C.704 maize hybrid seed production to planting pattern

    African Journals Online (AJOL)

    In order to determine the best planting pattern for producing the S.C.704 hybrid seed of maize, a field experiment was conducted in 2007 at Safiabad Dezful Research Center via a complete block design with four treatments and replicates each. The treatments were: D1 (one row each of paternal and maternal lines), D2 (two ...

  2. Patatin-related phospholipase A, pPLAIIIα, modulates the longitudinal growth of vegetative tissues and seeds in rice.

    Science.gov (United States)

    Liu, Guangmeng; Zhang, Ke; Ai, Jun; Deng, Xianjun; Hong, Yueyun; Wang, Xuemin

    2015-11-01

    Patatin-related phospholipase A (pPLA) hydrolyses glycerolipids to produce fatty acids and lysoglycerolipids. The Oryza sativa genome has 21 putative pPLAs that are grouped into five subfamilies. Overexpression of OspPLAIIIα resulted in a dwarf phenotype with decreased length of rice stems, roots, leaves, seeds, panicles, and seeds, whereas OspPLAIIIα-knockout plants had longer panicles and seeds. OspPLAIIIα-overexpressing plants were less sensitive than wild-type and knockout plants to gibberellin-promoted seedling elongation. OspPLAIIIα overexpression and knockout had an opposite effect on the expression of the growth repressor SLENDER1 in the gibberellin signalling process. OspPLAIIIα-overexpressing plants had decreased mechanical strength and cellulose content, but exhibited increases in the expression of several cellulose synthase genes. These results indicate that OspPLAIIIα plays a role in rice vegetative and reproductive growth and that the constitutive, high activity of OspPLAIIIα suppresses cell elongation. The decreased gibberellin response in overexpressing plants is probably a result of the decreased ability to make cellulose for anisotropic cell expansion. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  3. Specific roles of tocopherols and tocotrienols in seed longevity and germination tolerance to abiotic stress in transgenic rice.

    Science.gov (United States)

    Chen, Defu; Li, Yanlan; Fang, Tao; Shi, Xiaoli; Chen, Xiwen

    2016-03-01

    Tocopherols and tocotrienols are lipophilic antioxidants that are abundant in plant seeds. Although their roles have been extensively studied, our understanding of their functions in rice seeds is still limited. In this study, on the basis of available RNAi rice plants constitutively silenced for homogentisate phytyltransferase (HPT) and tocopherol cyclase (TC), we developed transgenic plants that silenced homogentisate geranylgeranyl transferase (HGGT). All the RNAi plants showed significantly reduced germination percentages and a higher proportion of abnormal seedlings than the control plants, with HGGT transgenics showing the most severe phenotype. The accelerated aging phenotype corresponded well with the amount of H2O2 accumulated in the embryo, glucose level, and ion leakage, but not with the amount of O(2-) accumulated in the embryo and lipid hydroperoxides levels in these genotypes. Under abiotic stress conditions, HPT and TC transgenics showed lower germination percentage and seedling growth than HGGT transgenics, while HGGT transgenics showed almost the same status as the wild type. Therefore, we proposed that tocopherols in the germ may protect the embryo from reactive oxygen species under both accelerated aging and stress conditions, whereas tocotrienols in the pericarp may exclusively help in reducing the metabolic activity of the seed during accelerated aging. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. Accumulation of long-lived mRNAs associated with germination in embryos during seed development of rice

    Science.gov (United States)

    Sano, Naoto; Ono, Hanako; Murata, Kazumasa; Yamada, Tetsuya; Hirasawa, Tadashi; Kanekatsu, Motoki

    2015-01-01

    Mature dry seeds contain translatable mRNAs called long-lived mRNAs. Early studies have shown that protein synthesis during the initial phase of seed germination occurs from long-lived mRNAs, without de novo transcription. However, the gene expression systems that generate long-lived mRNAs in seeds are not well understood. To examine the accumulation of long-lived mRNAs in developing rice embryos, germination tests using the transcriptional inhibitor actinomycin D (Act D) were performed with the Japonica rice cultivar Nipponbare. Although over 70% of embryos at 10 days after flowering (DAF) germinated in the absence of the inhibitor, germination was remarkably impaired in embryos treated with Act D. In contrast, more than 70% of embryos at 20, 25, 30 and 40 DAF germinated in the presence of Act D. The same results were obtained when another cultivar, Koshihikari, was used, indicating that the long-lived mRNAs required for germination predominantly accumulate in embryos between 10 and 20 DAF during seed development. RNA-Seq identified 529 long-lived mRNA candidates, encoding proteins such as ABA, calcium ion and phospholipid signalling-related proteins, and HSP DNA J, increased from 10 to 20 DAF and were highly abundant in 40 DAF embryos of Nipponbare and Koshihikari. We also revealed that these long-lived mRNA candidates are clearly up-regulated in 10 DAF germinating embryos after imbibition, suggesting that the accumulation of these mRNAs in embryos is indispensable for the induction of germination. The findings presented here may facilitate in overcoming irregular seed germination or producing more vigorous seedlings. PMID:25941326

  5. Genetic Control of a Transition from Black to Straw-White Seed Hull in Rice Domestication1[C][W][OA

    Science.gov (United States)

    Zhu, Bo-Feng; Si, Lizhen; Wang, Zixuan; Jingjie Zhu, Yan Zhou; Shangguan, Yingying; Lu, Danfeng; Fan, Danlin; Li, Canyang; Lin, Hongxuan; Qian, Qian; Sang, Tao; Zhou, Bo; Minobe, Yuzo; Han, Bin

    2011-01-01

    The genetic mechanism involved in a transition from the black-colored seed hull of the ancestral wild rice (Oryza rufipogon and Oryza nivara) to the straw-white seed hull of cultivated rice (Oryza sativa) during grain ripening remains unknown. We report that the black hull of O. rufipogon was controlled by the Black hull4 (Bh4) gene, which was fine-mapped to an 8.8-kb region on rice chromosome 4 using a cross between O. rufipogon W1943 (black hull) and O. sativa indica cv Guangluai 4 (straw-white hull). Bh4 encodes an amino acid transporter. A 22-bp deletion within exon 3 of the bh4 variant disrupted the Bh4 function, leading to the straw-white hull in cultivated rice. Transgenic study indicated that Bh4 could restore the black pigment on hulls in cv Guangluai 4 and Kasalath. Bh4 sequence alignment of all taxa with the outgroup Oryza barthii showed that the wild rice maintained comparable levels of nucleotide diversity that were about 70 times higher than those in the cultivated rice. The results from the maximum likelihood Hudson-Kreitman-Aguade test suggested that the significant reduction in nucleotide diversity in rice cultivars could be caused by artificial selection. We propose that the straw-white hull was selected as an important visual phenotype of nonshattered grains during rice domestication. PMID:21263038

  6. Comparative Phosphoproteomic Analysis of the Developing Seeds in Two Indica Rice ( Oryza sativa L.) Cultivars with Different Starch Quality.

    Science.gov (United States)

    Pang, Yuehan; Zhou, Xin; Chen, Yaling; Bao, Jinsong

    2018-03-21

    Protein phosphorylation plays important roles in regulation of various molecular events such as plant growth and seed development. However, its involvement in starch biosynthesis is less understood. Here, a comparative phosphoproteomic analysis of two indica rice cultivars during grain development was performed. A total of 2079 and 2434 phosphopeptides from 1273 and 1442 phosphoproteins were identified, covering 2441 and 2808 phosphosites in indica rice 9311 and Guangluai4 (GLA4), respectively. Comparative analysis identified 303 differentially phosphorylated peptides, and 120 and 258 specifically phosphorylated peptides in 9311 and GLA4, respectively. Phosphopeptides in starch biosynthesis related enzymes such as AGPase, SSIIa, SSIIIa, BEI, BEIIb, PUL, and Pho1were identified. GLA4 and 9311 had different amylose content, pasting viscosities, and gelatinization temperature, suggesting subtle difference in starch biosynthesis and regulation between GLA4 and 9311. Our study will give added impetus to further understanding the regulatory mechanism of starch biosynthesis at the phosphorylation level.

  7. Seeds of Camargue rice (Oryza Sativa L. Var Cigalon) and their responses to exposure to 60-Co gamma radiations. Study of the natural phenomenon of radiation protection

    International Nuclear Information System (INIS)

    Bayonove-Barthelemy, Jacqueline

    1978-01-01

    Within the frame of a project aiming at improving a technique of experimental mutagenesis (seed processing by cobalt-60 gamma rays), this research thesis reports the radiobiological characterization of Cigalon rice seeds, the adjustment of techniques of radiation protection, and the definition of processing and irradiation conditions which could reduce the undesirable physiological effects of cobalt-60 gamma radiation on rice seeds. The author reports the study of variations of physiological radio-sensitivity. Damages are assessed by comparing the growth of irradiated seeds with that of non-irradiated seeds. The mechanism of radiation natural protection is studied by comparing an inhibition in distilled water at two temperatures (5 and 24 C) with that obtained with cysteamine (an efficient radiation protection compound)

  8. Comparative proteomic analysis of rice after seed ground simulated radiation and spaceflight explains the radiation effects of space environment

    Science.gov (United States)

    Wang, Wei; Shi, Jinming; Liang, Shujian; Lei, Huang; Shenyi, Zhang; Sun, Yeqing

    In previous work, we compared the proteomic profiles of rice plants growing after seed space-flights with ground controls by two-dimensional difference gel electrophoresis (2-D DIGE) and found that the protein expression profiles were changed after seed space environment exposures. Spaceflight represents a complex environmental condition in which several interacting factors such as cosmic radiation, microgravity and space magnetic fields are involved. Rice seed is in the process of dormant of plant development, showing high resistance against stresses, so the highly ionizing radiation (HZE) in space is considered as main factor causing biological effects to seeds. To further investigate the radiation effects of space environment, we performed on-ground simulated HZE particle radiation and compared between the proteomes of seed irra-diated plants and seed spaceflight (20th recoverable satellite) plants from the same rice variety. Space ionization shows low-dose but high energy particle effects, for searching the particle effects, ground radiations with the same low-dose (2mGy) but different liner energy transfer (LET) values (13.3KeV/µm-C, 30KeV/µm-C, 31KeV/µm-Ne, 62.2KeV/µm-C, 500Kev/µm-Fe) were performed; using 2-D DIGE coupled with clustering and principle component analysis (PCA) for data process and comparison, we found that the holistic protein expression patterns of plants irradiated by LET-62.2KeV/µm carbon particles were most similar to spaceflight. In addition, although space environment presents a low-dose radiation (0.177 mGy/day on the satellite), the equivalent simulated radiation dose effects should still be evaluated: radiations of LET-62.2KeV/µm carbon particles with different cumulative doses (2mGy, 20mGy, 200mGy, 2000mGy) were further carried out and resulted that the 2mGy radiation still shared most similar proteomic profiles with spaceflight, confirming the low-dose effects of space radiation. Therefore, in the protein expression level

  9. Low hybrid onion seed yields relate to honey bee visits and insecticide use

    Directory of Open Access Journals (Sweden)

    Rachael Long

    2011-07-01

    Full Text Available Onion thrips, previously considered of minor importance to hybrid onion seed production in California, vector the newly introduced iris yellow spot virus, a serious pathogen of onions that can cause significant yield losses. Insecticide use to control onion thrips has increased in onion seed fields, coincident with a steep decrease in yields, especially in Colusa County. We examined a number of possible contributing factors and found a strong positive correlation between honey bee activity and onion seed set, indicating that a lack of pollination may be contributing to the reduced yields. In addition, honey bee visits to onion flowers were negatively correlated with the number of insecticides applied per field and field size. Reduced onion seed yields in recent years could be associated with the increase in insecticide use, which may be repelling or killing honey bees, important pollinators of this crop.

  10. Levels of Crotonaldehyde and 4-hydroxy-(E-2-nonenal and Expression of Genes Encoding Carbonyl-Scavenging Enzyme at Critical Node During Rice Seed Aging

    Directory of Open Access Journals (Sweden)

    Fu Shenzao

    2018-05-01

    Full Text Available Abstract:: The critical node (CN is an important stage during seed aging, which is related to effective genebank conservation. Previous studies have demonstrated that proteins undergo carbonylated modification at the CN in rice, indicating oxidative damage. However, the levels of reactive carbonyl species (RCS and the associated scavenging system at the CN are largely unknown. In this study, we optimized methods for the extraction and analysis of RCS from dry rice embryos. In order to acquire seeds at the CN, rice seeds were subjected to natural conditions for 7, 9, 11 and 13 months, and the seed germination rates were reduced to 90%, 82%, 71% and 57%, respectively. We chose the stage with seed germination rate of 82% as the CN according to the rice seed vigor loss curve. The levels of crotonaldehyde and 4-hydroxy-(E-2-nonenal (HNE were significantly increased at the CN. In addition, genes encoding carbonyl-scavenging enzyme, including OsALDHs and OsAKRs, were significantly down-regulated at the CN, and reductions in the expression of OsALDH2-2, OsALDH2-5, OsALDH3-4, OsALDH7, OsAKR1 and OsAKR2 in particular could be responsible for RCS accumulation. Thus, the accumulations of crotonaldehyde and HNE and down-regulation of genes encoding carbonyl-scavenging enzyme might be related to an accelerating loss of seed viability at the CN. Key words: carbonyl-scavenging system, reactive carbonyl species, seed aging, crotonaldehyde, critical node, rice storage

  11. Dynamic changes in the distribution of minerals in relation to phytic acid accumulation during rice seed development.

    Science.gov (United States)

    Iwai, Toru; Takahashi, Michiko; Oda, Koshiro; Terada, Yasuko; Yoshida, Kaoru T

    2012-12-01

    Phytic acid (inositol hexakisphosphate [InsP(6)]) is the storage compound of phosphorus in seeds. As phytic acid binds strongly to metallic cations, it also acts as a storage compound of metals. To understand the mechanisms underlying metal accumulation and localization in relation to phytic acid storage, we applied synchrotron-based x-ray microfluorescence imaging analysis to characterize the simultaneous subcellular distribution of some mineral elements (phosphorus, calcium, potassium, iron, zinc, and copper) in immature and mature rice (Oryza sativa) seeds. This fine-imaging method can reveal whether these elements colocalize. We also determined their accumulation patterns and the changes in phosphate and InsP(6) contents during seed development. While the InsP(6) content in the outer parts of seeds rapidly increased during seed development, the phosphate contents of both the outer and inner parts of seeds remained low. Phosphorus, calcium, potassium, and iron were most abundant in the aleurone layer, and they colocalized throughout seed development. Zinc was broadly distributed from the aleurone layer to the inner endosperm. Copper localized outside the aleurone layer and did not colocalize with phosphorus. From these results, we suggest that phosphorus translocated from source organs was immediately converted to InsP(6) and accumulated in aleurone layer cells and that calcium, potassium, and iron accumulated as phytic acid salt (phytate) in the aleurone layer, whereas zinc bound loosely to InsP(6) and accumulated not only in phytate but also in another storage form. Copper accumulated in the endosperm and may exhibit a storage form other than phytate.

  12. Identification of QTLs for seed germination capability after various storage periods using two RIL populations in rice.

    Science.gov (United States)

    Jiang, Wenzhu; Lee, Joohyun; Jin, Yong-Mei; Qiao, Yongli; Piao, Rihua; Jang, Sun Mi; Woo, Mi-Ok; Kwon, Soon-Wook; Liu, Xianhu; Pan, Hong-Yu; Du, Xinglin; Koh, Hee-Jong

    2011-04-01

    Seed germination capability of rice is one of the important traits in the production and storage of seeds. Quantitative trait loci (QTL) associated with seed germination capability in various storage periods was identified using two sets of recombinant inbred lines (RILs) which derived from crosses between Milyang 23 and Tong 88-7 (MT-RILs) and between Dasanbyeo and TR22183 (DT-RILs). A total of five and three main additive effects (QTLs) associated with seed germination capability were identified in MT-RILs and DT-RILs, respectively. Among them, six QTLs were identified repeatedly in various seed storage periods designated as qMT-SGC5.1, qMT-SGC7.2, and qMT-SGC9.1 on chromosomes 5, 7, and 9 in MT-RILs, and qDT-SGC2.1, qDT-SGC3.1, and qDT-SGC9.1 on chromosomes 2, 3, and 9 in DT-RILs, respectively. The QTL on chromosome 9 was identified in both RIL populations under all three storage periods, explaining up to 40% of the phenotypic variation. Eight and eighteen pairs additive × additive epistatic effect (epistatic QTL) were identified in MT-RILs and DT-RILs, respectively. In addition, several near isogenic lines (NILs) were developed to confirm six repeatable QTL effects using controlled deterioration test (CDT). The identified QTLs will be further studied to elucidate the mechanisms controlling seed germination capability, which have important implications for long-term seed storage.

  13. Induced mutants for the improvement of sesame and hybrid seed production

    International Nuclear Information System (INIS)

    Murty, G.S.S.

    2001-01-01

    With an overall objective to develop hybrids in sesame, induced mutants were used in cross breeding and five initial yield trials were conducted. For obtaining the mutant hybrids, recessive morphological mutants were used as female, and check varieties as male parents. In each trial, seed yields of mutant hybrids were compared with: i) the original parent in which the mutants were induced, ii) best check variety and iii) best cultivar hybrid. Among 138 mutant hybrids evaluated between 1994 and 1997, 18 showed superiority. In the development of hybrids, it is also desirable to have male sterile lines. By irradiating seeds with 400 Gy gamma rays, four genetic male sterile mutants were isolated. One of them, TMST-11 appears to be promising for breeding programme showing 100% male sterility and characterised by dark green foliage. To study the percent outcrossing, a monogenic chlorina mutant which can be identified from the seedling stage, was used in experiments conducted for two years. Among open pollinated plants, 92-98% plants were found outcrossed. Based on plant to row progenies, percent outcrossing ranged between 0.0 to 13.8%. (author)

  14. Biochemical changes in hybrid pumpkin seeds at different stages of maturation

    Directory of Open Access Journals (Sweden)

    Patrícia Pereira da Silva

    Full Text Available ABSTRACT This study aimed to evaluate biochemical changes in seeds of the pumpkin hybrid, 'Jabras', from fruit harvested at different stages of maturation (15, 30, 45, 60 and 75 days after anthesis. Thirty fruit were harvested at each stage, with the seeds from 15 of the fruit being extracted immediately. The remaining 15 were stored for twenty days in plastic boxes and the seeds extracted after this period. After processing and drying the seeds, the following were determined: moisture content, germination, first count and antioxidant enzyme activity (peroxidase, ascorbate peroxidase, catalase and superoxide dismutase. Seeds from the fruit harvested at 30 DAA displayed low values for germination and vigour and high antioxidant enzyme activity, indicating that they were immature and that drying possibly caused damage to the system of cell membranes. The results obtained in this study demonstrated that analysis related to changes in the activity of enzymes during development and maturation of the seeds was effective in evaluating the physiological and biochemical changes in pumpkin seeds of the 'Jabras' cultivar.

  15. Effects of seed mixture sowing with transgenic Bt rice and its parental line on the population dynamics of target stemborers and leafrollers, and non-target planthoppers.

    Science.gov (United States)

    Li, Zhuo; Li, Li-Kun; Liu, Bin; Wang, Long; Parajulee, Megha N; Chen, Fa-Jun

    2018-01-24

    The widespread planting of insect-resistant crops has caused a dramatic shift in agricultural landscapes, thus raising concerns about the potential impacts on both target and non-target pests. In this study, we examined the potential effects of intra-specific seed mixture sowing with transgenic Bt rice (Bt) and its parental non-transgenic line (Nt) (100% Bt rice [Bt 100 ], 5% Nt+95% Bt [Nt 05 Bt 95 ], 10% Nt+90% Bt [Nt 10 Bt 90 ], 20% Nt+80% Bt [Nt 20 Bt 80 ], 40% Nt+60% Bt [Nt 40 Bt 60 ] and 100% Nt rice [Nt 100 ]) on target and non-target pests in a 2-year field trial in southern China. The occurrence of target pests, Sesamia inferens, Chilo suppressalis and Cnaphalocrocis medinalis, decreased with the increased ratio of Bt rice, and the mixture ratios with more than 90% Bt rice (Bt 100 and Nt 05 Bt 95 ) significantly increased the pest suppression efficiency, with the lowest occurrences of non-target planthoppers, Nilaparvata lugens and Sogatella furcifera in Nt 100 and Nt 05 Bt 95 . Furthermore, there were no significant differences in 1000-grain dry weight and grain dry weight per 100 plants between Bt 100 and Nt 05 Bt 95 . Seed mixture sowing of Bt rice with ≤10% (especially 5%) of its parent line was sufficient to overcome potential compliance issues that exist with the use of block or structured refuge to provide most effective control of both target and non-target pests without compromising the grain yield. It is also expected that the strategy of seed mixture sowing with transgenic Bt rice and the non-transgenic parental line would provide rice yield stability while decreasing the insecticide use frequency in rice production. © 2018 Institute of Zoology, Chinese Academy of Sciences.

  16. Molecular Breeding of Rice Restorer Lines and Hybrids for Brown Planthopper (BPH) Resistance Using the Bph14 and Bph15 Genes.

    Science.gov (United States)

    Wang, Hongbo; Ye, Shengtuo; Mou, Tongmin

    2016-12-01

    The development of hybrid rice is a practical approach for increasing rice production. However, the brown planthopper (BPH), Nilaparvata lugens Stål, causes severe yield loss of rice (Oryza sativa L.) and can threaten food security. Therefore, breeding hybrid rice resistant to BPH is the most effective and economical strategy to maintain high and stable production. Fortunately, numerous BPH resistance genes have been identified, and abundant linkage markers are available for molecular marker-assisted selection (MAS) in breeding programs. Hence, we pyramided two BPH resistance genes, Bph14 and Bph15, into a susceptive CMS restorer line Huahui938 and its derived hybrids using MAS to improve the BPH resistance of hybrid rice. Three near-isogenic lines (NILs) with pyramided Bph14 and Bph15 were obtained by molecular marker-assisted backcross (MAB) and phenotypic selection. The genomic components of these NILs were detected using the whole-genome SNP (Single nucleotide polymorphism) array, RICE6K, suggesting that the recurrent parent genome (RPG) recovery of the NILs was 87.88, 87.70 and 86.62 %, respectively. BPH bioassays showed that the improved NILs and their derived hybrids carrying homozygous Bph14 and Bph15 were resistant to BPH. However, the hybrids with heterozygous Bph14 and Bph15 remained susceptible to BPH. The developed NILs showed no significant differences in major agronomic traits and rice qualities compared with the recurrent parent. Moreover, the improved hybrids derived from the NILs exhibited better agronomic performance and rice quality compared with the controls under natural field conditions. This study demonstrates that it is essential to stack Bph14 and Bph15 into both the maternal and paternal parents for developing BPH-resistant hybrid rice varieties. The SNP array with abundant DNA markers is an efficient tool for analyzing the RPG recovery of progenies and can be used to monitor the donor segments in NILs, thus being extremely important

  17. Seed oil triglyceride profiling of thirty-two hybrid grape varieties.

    Science.gov (United States)

    De Marchi, Fabiola; Seraglia, Roberta; Molin, Laura; Traldi, Pietro; De Rosso, Mirko; Panighel, Annarita; Dalla Vedova, Antonio; Gardiman, Massimo; Giust, Mirella; Flamini, Riccardo

    2012-09-01

    Triglyceride profile of seed oil samples from 32 hybrid grape varieties not studied before was investigated. A new method for the analysis of triacylglycerols (TAGs) has been developed based on the direct infusion in the electrospray ionization (ESI) source and employing tetrahydrofuran/methanol/water (85:10:5 v|v|v) as solvent; the formation of [M + Na](+) ions in high yield has been observed. TAGs were identified by ESI-tandem mass spectrometry analysis, and the matrix-assisted-laser-desorption-ionization and time-of-flight profile of samples was determined. Six were the principal TAGs identified in seed oil: trilinolein (LLL) was the most abundant (43%), followed by dilinoleoyl-oleoylglycerol (LOL, 23%), and dilinoleoyl-palmitoylglycerol (LPL, 15%). Compounds present in lower concentration were LSL and LOO (11%), LOP (6%), and LSP (2%). Compared with seed oils produced from V. Vinifera grapes, some significant differences in the relative abundances of TAGs were found, in particular hybrid grape seed oils showed higher LOL and lower LPL content, respectively. Among the samples studied, a particularly high content of LLL (rich in unsaturated fatty acids) was found in seed oils from two red varieties. Copyright © 2012 John Wiley & Sons, Ltd.

  18. A novel male sterility-fertility restoration system in plants for hybrid seed production.

    Science.gov (United States)

    Singh, Surendra Pratap; Singh, Sudhir P; Pandey, Tripti; Singh, Ram Rakshpal; Sawant, Samir V

    2015-06-15

    Hybrid seeds are used for stimulated crop production, as they harness heterosis. The achievement of complete male-sterility in the female-parent and the restored-fertility in F1-hybrids are the major bottlenecks in the commercial hybrid seed production. Here, we report a male sterility-fertility restoration system by engineering the in most nutritive anther wall layer tapetum of female and male parents. In the female parent, high-level, and stringent expression of Arabidopsis autophagy-related gene BECLIN1 was achieved in the tapetum, which altered the tapetal degeneration program, leading to male sterility. This works on our previously demonstrated expression cassette based on functional complementation of TATA-box mutant (TGTA) promoter and TATA-binding protein mutant3 (TBPm3), with modification by conjugating Long Hypocotyle in Far-Red1 fragment (HFR1(NT131)) with TBPm3 (HFR1(NT131)-TBPm3) to exercise regulatory control over it. In the male parent, tapetum-specific Constitutive photo-morphogenesis1 (COP1) was expressed. The F1 obtained by crossing these engineered parents showed decreased BECLIN1 expression, which was further completely abolished when COP1-mutant (COP1(L105A)) was used as a male parent, leading to normal tapetal development and restored fertility. The system works on COP1-HFR1 interaction and COP1-mediated degradation of TBPm3 pool (HFR1(NT131)-TBPm3). The system can be deployed for hybrid seed production in agricultural crops.

  19. 15N tracer technique for studying efficiency of deep placed fertilizer through nutriseed holder in direct seeded rice

    International Nuclear Information System (INIS)

    Asha, V.S.; Arulmozhiselvan, K.

    2006-01-01

    In order to estimate N use efficiency in deep placement of NPK straight fertilizers, two pot experiments were conducted in high clay soil with direct seeded rice. 15 N urea was used as a tracer. A newly designed 'Nutriseed Holder' was used for simultaneous deep placement of fertilizers and sowing of seeds. Each holder had two cavities, one on top for holding seed and another one at bottom for holding fertilizer material. By implanting a holder in puddled soil, a rice hill was established. The length (5 or 10 cm) and width (8 or 12 mm) of nutriseed holder was standardized while evaluating the effect of Azolla, neem and seed inoculants. Appreciably, deep placement of plain NPK fertilizer in 12 mm holder placed at 5 cm depth recorded the highest grain yield with a yield increase of 81.8 per cent during rabi 2002 (cv CO 43) and 84.8 per cent during summer 2003 (cv CO 47) over broadcast application. Further, it increased recovery of added JSN in grain + straw to the tune of 57.1 per cent in rabi and 54.7 per cent in summer as compared to broadcast application (26.1% in rabi, 34.2 in summer). Deep placement enhanced more retention in soil (up to 9.0% in rabi, 14.6% in summer) whereas broadcast application enhanced more retention in Azolla biomass that was grown in floodwater (up to 2.3 % in rabi, 4.3 % in summer). Use of 12 mm width nutriseed holder aiding deep placement at 5 cm depth was found suitable for deriving high yield and N use efficiency. (author)

  20. Low-energy N-ion beam biotechnology application in the induction of Thai jasmine rice mutant with improved seed storability

    Science.gov (United States)

    Semsang, Nuananong; Techarang, Jiranat; Yu, Liangdeng; Phanchaisri, Boonrak

    2018-06-01

    Low-energy heavy-ion beam is a novel biotechnology used for mutation induction in plants. We used a low-energy N-ion beam to induce mutations in Thai jasmine rice (Oryza sativa L. cv. KDML 105) to improve the yield and seed quality. Seeds of BKOS6, a Thai jasmine rice mutant previously induced by ion beams, were re-bombarded with 60-kV-accelerated N-ions (N++N2+) to fluences of 1-2 × 1016 ions/cm2. The resulting mutant, named HyKOS21, exhibited photoperiod insensitivity, semi-dwarfness, and high yield potential. Seed storability of the mutant was studied in natural and accelerated ageing conditions and compared to that of KDML 105 and six other Thai rice varieties. In both testing conditions, HyKOS21 mutant had the highest seed storability among the tested varieties. After storage in the natural condition for 18 months, HyKOS21 had a seed germination percentage nearly two times as that of the original KDML 105. Biochemical analysis showed that the lipid peroxidation level of the mutant seeds was the lowest among those of the tested varieties. Furthermore, an expression analysis of genes encoding lipoxygenase isoenzyme (lox1, lox2, and lox3) revealed that the mutant lacked expression of lox1 and lox2 and expressed only lox3 in seeds. These results may explain the improved seed longevity of the mutant after storage. This work provides further evidence of the modification of biological materials using a low-energy ion beam to produce rice mutants with improved yield and seed storability. The benefits of this technology, to create new varieties with improved values, could serve for local economic development.

  1. Differential activity of Striga hermonthica seed germination stimulants and Gigaspora rosea hyphal branching factors in rice and their contribution to underground communication.

    Directory of Open Access Journals (Sweden)

    Catarina Cardoso

    Full Text Available Strigolactones (SLs trigger germination of parasitic plant seeds and hyphal branching of symbiotic arbuscular mycorrhizal (AM fungi. There is extensive structural variation in SLs and plants usually produce blends of different SLs. The structural variation among natural SLs has been shown to impact their biological activity as hyphal branching and parasitic plant seed germination stimulants. In this study, rice root exudates were fractioned by HPLC. The resulting fractions were analyzed by MRM-LC-MS to investigate the presence of SLs and tested using bioassays to assess their Striga hermonthica seed germination and Gigaspora rosea hyphal branching stimulatory activities. A substantial number of active fractions were revealed often with very different effect on seed germination and hyphal branching. Fractions containing (--orobanchol and ent-2'-epi-5-deoxystrigol contributed little to the induction of S. hermonthica seed germination but strongly stimulated AM fungal hyphal branching. Three SLs in one fraction, putative methoxy-5-deoxystrigol isomers, had moderate seed germination and hyphal branching inducing activity. Two fractions contained strong germination stimulants but displayed only modest hyphal branching activity. We provide evidence that these stimulants are likely SLs although no SL-representative masses could be detected using MRM-LC-MS. Our results show that seed germination and hyphal branching are induced to very different extents by the various SLs (or other stimulants present in rice root exudates. We propose that the development of rice varieties with different SL composition is a promising strategy to reduce parasitic plant infestation while maintaining symbiosis with AM fungi.

  2. Construction of a multicontrol sterility system for a maize male-sterile line and hybrid seed production based on the ZmMs7 gene encoding a PHD-finger transcription factor.

    Science.gov (United States)

    Zhang, Danfeng; Wu, Suowei; An, Xueli; Xie, Ke; Dong, Zhenying; Zhou, Yan; Xu, Liwen; Fang, Wen; Liu, Shensi; Liu, Shuangshuang; Zhu, Taotao; Li, Jinping; Rao, Liqun; Zhao, Jiuran; Wan, Xiangyuan

    2018-02-01

    Although hundreds of genetic male sterility (GMS) mutants have been identified in maize, few are commercially used due to a lack of effective methods to produce large quantities of pure male-sterile seeds. Here, we develop a multicontrol sterility (MCS) system based on the maize male sterility 7 (ms7) mutant and its wild-type Zea mays Male sterility 7 (ZmMs7) gene via a transgenic strategy, leading to the utilization of GMS in hybrid seed production. ZmMs7 is isolated by a map-based cloning approach and encodes a PHD-finger transcription factor orthologous to rice PTC1 and Arabidopsis MS1. The MCS transgenic maintainer lines are developed based on the ms7-6007 mutant transformed with MCS constructs containing the (i) ZmMs7 gene to restore fertility, (ii) α-amylase gene ZmAA and/or (iii) DNA adenine methylase gene Dam to devitalize transgenic pollen, (iv) red fluorescence protein gene DsRed2 or mCherry to mark transgenic seeds and (v) herbicide-resistant gene Bar for transgenic seed selection. Self-pollination of the MCS transgenic maintainer line produces transgenic red fluorescent seeds and nontransgenic normal colour seeds at a 1:1 ratio. Among them, all the fluorescent seeds are male fertile, but the seeds with a normal colour are male sterile. Cross-pollination of the transgenic plants to male-sterile plants propagates male-sterile seeds with high purity. Moreover, the transgene transmission rate through pollen of transgenic plants harbouring two pollen-disrupted genes is lower than that containing one pollen-disrupted gene. The MCS system has great potential to enhance the efficiency of maize male-sterile line propagation and commercial hybrid seed production. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  3. A suitable pricing strategy for hybrid maize seed in South Africa

    OpenAIRE

    2012-01-01

    M.B.A. A general increase in price elasticity on farming inputs as well as increasing pressure on South African subsidiaries of international companies makes it important for a well-planned pricing strategy. This is accentuated by the fact that pricing is normally done only once a year in seed companies in South Africa, and customers are unlikely to accept more frequent price changes. The aim of this study is to determine a suitable pricing strategy for hybrid maize seed for Monsanto in So...

  4. Development and Validation of a TaqMan Real-Time PCR Assay for the Specific Detection and Quantification of Fusarium fujikuroi in Rice Plants and Seeds.

    Science.gov (United States)

    Carneiro, Greice Amaral; Matić, Slavica; Ortu, Giuseppe; Garibaldi, Angelo; Spadaro, Davide; Gullino, Maria Lodovica

    2017-07-01

    Bakanae disease, which is caused by the seedborne pathogen Fusarium fujikuroi, is found throughout the world on rice. A TaqMan real-time PCR has been developed on the TEF 1-α gene to detect F. fujikuroi in different rice tissues. Three primer/probe sets were tested. The selected set produced an amplicon of 84 bp and was specific for F. fujikuroi with respect to eight Fusarium species of rice and six other rice common pathogens. The assay was validated for specificity, selectivity, sensitivity, repeatability, and reproducibility. The detection limit was set at 27.5 fg of DNA, which is approximately equivalent to one haploid genome of F. fujikuroi. The developed TaqMan real-time assay was able to efficiently detect and quantify F. fujikuroi from rice culms, leaves, roots, and seeds. At 1 week post-germination (wpg), the pathogen was more diffused in the green tissues, while at 3 wpg it was uniformly spread also in the roots. The highest concentration of F. fujikuroi was measured in the M6 cultivar, which showed around 1,450 fungal cells/g. The assay was sufficiently sensitive to detect a few genomic equivalents in the rice seeds, corresponding to 9.89 F. fujikuroi cells/g. The assay permitted bakanae disease to be detected in asymptomatic tissues at the early rice development stages.

  5. Pengaruh pemberian abu sekam padi sebagai bahan desikan pada penyimpanan benih terhadap daya tumbuh dan pertumbuhan bibit kakao (The effects of rice husk ash as desiccation material of seed storage on viability and cocoa seedling growth.

    Directory of Open Access Journals (Sweden)

    Pudji Rahardjo

    2012-08-01

    Full Text Available Rice husk ash as desiccation material can be used to maintain seed viability in storage through its ability to absorb humidity during its storage. High relative humidity caused seed moisture content to increase so the respiration rate of seed increases and uses faster food stock. Finally the viability of seed is lost. A research on use of rice husk ash as desiccation material of cocoa seed storage was conducted in Agronomy Laboratory and Kaliwining Experimental Station, Indonesian Coffee and Cocoa Research Institute. Completely Randomized Design was used in this research with treatment of rice husk ash application on cocoa seed as follows: 0 g/100 seeds (A, 5 g/100 seeds (B, 10 g/100 seeds (C, 15 g/100 seeds (D, and 20 g/100 seeds (E. This experiment used four replications. Cocoa seeds were stored in plastic bag within carton box in ambient temperature. The storage periods were 1, 2, and 3 weeks, and parameters of observation consisted of electrical conductivity of dipped water of cocoa seeds, percentage of seed germination, percentage of seed emergence, early growth parameters at one month old including seedlings height of seedling, diameter, leaf number, root length, and dry weight. The result of the experiment showed that the use of rice husk ash at 5-10 g/100 seeds could maintain electrical conductivity of dipped water at low level, percentage of seed germination at 99-100 % and percentage of seed emergence at 79-91% after two weeks storage. The use of rice husk ash at 5-10 g/100 seeds after two weeks storage affected height of cacao seedling, but did not affected stem diameters, leaf numbers, root lengths, and dry weights

  6. Exploitation of alfalfa seed (Medicago sativa L.) flour into gluten-free rice cookies: Nutritional, antioxidant and quality characteristics.

    Science.gov (United States)

    Giuberti, Gianluca; Rocchetti, Gabriele; Sigolo, Samantha; Fortunati, Paola; Lucini, Luigi; Gallo, Antonio

    2018-01-15

    In an effort to increase the nutritional value of common gluten-free (GF) cereal-based foods, GF cookies using alfalfa seed flour (ASF), at different substitution levels to common rice flour (0% as control, 15%, 30% and 45% w/w), were produced. Crude protein, total dietary fibre, total polyunsaturated, total n-3 and n-6 fatty acid contents increased linearly (p<0.05) by raising the substitution levels of rice with ASF. The hardness, the total phenolic content, the in vitro antioxidant capacity and the resistant starch increased linearly (p<0.05), whereas the starch hydrolysis index decreased linearly (p<0.05) by raising the substitution levels of rice flour with ASF. Despite the fact that ASF-substituted GF cookies had inferior sensory attributes compared to the control, the score given by the panellists remained at fairly good levels for all tested parameters, showing acceptability of the substituted GF cookies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Pyramiding and evaluation of three dominant brown planthopper resistance genes in the elite indica rice 9311 and its hybrids.

    Science.gov (United States)

    Hu, Jie; Cheng, Mingxing; Gao, Guanjun; Zhang, Qinglu; Xiao, Jinghua; He, Yuqing

    2013-07-01

    Brown planthopper (BPH), Nilaparvata lugens Stål, is the most devastating insect pest in rice-producing areas. Three dominant BPH resistance genes (Bph14, Bph15, Bph18) were pyramided into elite indica rice 9311 and its hybrids using marker-assisted selection. Gene effectiveness was evaluated on the basis of seedling and adult rice resistance, honeydew weight and survival rate of BPH. All three genes affected BPH growth and development and antibiotic factors, resulting in both seedling and adult resistance. Bph15 had the greatest effect on conferring resistance to BPH. The results showed an additive effect of pyramiding genes, the order of the gene effect being 14/15/18 ≥ 14/15 > 15/18 ≥ 15 > 14/18 ≥ 14 ≥ 18 > none. The pyramided or single-gene introgression hybrids showed greater resistance than conventional hybrids, although the heterozygous genotypes had weaker effects than the corresponding homozygous genotypes. Furthermore, field trial data demonstrated that yields of improved 9311 lines were higher than or similar to that of the control under natural field conditions. These improved versions can be immediately used in hybrid improvement and production. Compared with controls, pyramided lines and hybrids with three genes showed the strongest resistance to BPH, without a yield decrease. © 2012 Society of Chemical Industry.

  8. Effects of elevated ozone, carbon dioxide, and the combination of both on the grain quality of Chinese hybrid rice

    International Nuclear Information System (INIS)

    Wang, Yunxia; Song, Qiling; Frei, Michael; Shao, Zaisheng; Yang, Lianxin

    2014-01-01

    The effects of CO 2 and/or O 3 elevation on rice grain quality were investigated in chamber experiments with gas fumigation performed from transplanting until maturity in 2011 and 2012. Compared with the control (current CO 2 and O 3 concentration), elevated CO 2 caused a tendency of an increase in grain chalkiness and a decrease in mineral nutrient concentrations. In contrast, elevated O 3 significantly increased grain chalkiness and the concentrations of essential nutrients, while changes in starch pasting properties indicated a trend of deterioration in the cooking and eating quality. In the combination of elevated CO 2 and O 3 treatment, only chalkiness degree was significantly affected. It is concluded that the O 3 concentration projected for the coming few decades will have more substantial effects on grain quality of Chinese hybrid rice than the projected high CO 2 concentration alone, and the combination of two gases caused fewer significant changes in grain quality than individual gas treatments. - Highlights: • We investigated the effects of carbon dioxide and/or ozone elevation on rice grain quality. • Elevated ozone concentration had substantial effects on grain quality under current carbon dioxide concentration. • Elevated carbon dioxide concentration mitigated the impact of elevated ozone concentration on rice grain quality. - Exposure of Chinese hybrid rice to elevated ozone and CO 2 during growth causes fewer changes in grain quality than ozone exposure alone

  9. Fabrication and Performance Test of Aluminium Alloy-Rice Husk Ash Hybrid Metal Matrix Composite as Industrial and Construction Material

    Directory of Open Access Journals (Sweden)

    Md. Rahat Hossain

    2017-12-01

    Full Text Available Aluminium matrix composites (AMCs used extensively in various engineering fields due to their exceptional mechanical properties. In this present study, aluminium matrix composites (AMCs such as aluminium alloy (A356 reinforced with rice husk ash particles (RHA are made to explore the possibilities of reinforcing aluminium alloy. The stir casting method was applied to produce aluminium alloy (A356 reinforced with various amounts of (2%, 4%, and 6% rice husk ash (RHA particles. Physical treatment was carried out before the rice husk ash manufacturing process. The effect of mechanical strength of the fabricated hybrid composite was investigated. Therefore, impact test, tensile stress, compressive stress, and some other tests were carried out to analyse the mechanical properties. From the experimental results, it was found that maximum tensile, and compressive stress were found at 6% rice husk ash (RHA and aluminium matrix composites (AMCs. In future, the optimum percentages of rice husk ash (RHA to fabricate the hybrid composites will be determined. Also, simulation by finite element method (FEM will be applied for further investigation.

  10. Developing eco-friendly biofungicide for the management of major seed borne diseases of rice and assessing their physical stability and storage life.

    Science.gov (United States)

    Naveenkumar, Ramasamy; Muthukumar, Arjunan; Sangeetha, Ganesan; Mohanapriya, Ramanathan

    2017-04-01

    Three plant oils (Cymbopogon citratus, Cymbopogon martini, and Pelargonium graveolens) were developed as EC formulations and tested for their physical stabilities. EC formulations (10EC, 20EC and 30EC) of C. citratus, C. martini and P. graveolens had emulsion stability, spontaneity property, heat and cold stability. EC formulated plant oils were screened against the major seed borne fungi of rice such as Curvularia lunata, Fusarium moniliforme, Bipolaris oryzae, and Sarocladium oryzae. The level of inhibition varied among the concentrations of EC formulations. Among the three EC formulations, that of C. citratus oil 30EC recorded 100% inhibition on the mycelial growth of test pathogens. In the blotter paper method, rice seeds treated with a formulation of C. citratus oil 30EC controlled the infection of C. lunata, F. moniliforme, B. oryzae and S. oryzae in rice seed to the tune of 66.0%, 60.4%, 66.0% and 69.1%, respectively. Seed soaking with formulation of C. citratus oil 30EC showed the highest percentage of normal seedlings, the lowest number of abnormal seedling and fresh ungerminated seeds when tested with the roll-towel method. Seed soaking with 30EC formulation of C. citratus oil increased seed germination, shoot length, root length and vigour of rice seedlings when tested with the plastic tray method. Transmission of pathogens from seed to seedling was reduced significantly by the 30EC formulation of C. citratus oil when tested with the plastic pot method. The effect of the storage life of the 30EC formulation of C. citratus oil showed that it had retained their antifungal effect till the end of the incubation period (120 days), and is able to inhibit the mycelial growth of all test pathogens to the 100% level. Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

  11. Hybrid ternary rice paper-manganese oxide-carbon nanotube nanocomposites for flexible supercapacitors

    Science.gov (United States)

    Jiang, Wenchao; Zhang, Kaixi; Wei, Li; Yu, Dingshan; Wei, Jun; Chen, Yuan

    2013-10-01

    Modern portable electronic devices create a strong demand for flexible energy storage devices. Paper based nanocomposites are attractive as sustainable materials for such applications. Here, we directly explored the hydroxyl chemistry of cellulose fibers to synthesize hybrid ternary nanocomposites, comprised of rice paper, single-walled carbon nanotubes (SWCNTs) and manganese oxide nanoparticles. The functional groups on cellulose fibers can react with adsorbed permanganate ions, resulting in uniform deposition of manganese oxide nanoparticles. SWCNTs coated on top of manganese oxide nanoparticles form a highly conductive network connecting individual manganese oxide particles. By using the hybrid ternary composites as electrodes, the assembled two-electrode supercapacitors demonstrated high capacitance (260.2 F g-1), energy (9.0 W h kg-1), power (59.7 kW kg-1), and cycle stability (12% drop after 3000 cycles). In addition, the nanocomposites show good strength and excellent mechanical flexibility, and their capacitance shows negligible changes after bending more than 100 times. These findings suggest that opportunities exist to further explore the rich chemistry of cellulose fibers for innovative energy applications.Modern portable electronic devices create a strong demand for flexible energy storage devices. Paper based nanocomposites are attractive as sustainable materials for such applications. Here, we directly explored the hydroxyl chemistry of cellulose fibers to synthesize hybrid ternary nanocomposites, comprised of rice paper, single-walled carbon nanotubes (SWCNTs) and manganese oxide nanoparticles. The functional groups on cellulose fibers can react with adsorbed permanganate ions, resulting in uniform deposition of manganese oxide nanoparticles. SWCNTs coated on top of manganese oxide nanoparticles form a highly conductive network connecting individual manganese oxide particles. By using the hybrid ternary composites as electrodes, the assembled two

  12. Desempenho de populações híbridas F2 de arroz-vermelho (Oryza sativa com arroz transgênico (O. sativa resistente ao herbicida amonio-glufosinate Performance of F2 hybrid populations of red rice (Oryza sativa with ammonium-glufosinate-resistant transgenic rice (O. sativa

    Directory of Open Access Journals (Sweden)

    J.A. Noldin

    2004-09-01

    -preto. Mesmo assim, os usuários dessa tecnologia deverão adotar, obrigatoriamente, medidas que evitem a possibilidade de cruzamento entre o arroz transgênico e o arroz-vermelho ou arroz-preto.Red rice is an important weed in paddy rice fields. The use of ammonium glufosinate - resistant genetically modified (GM rice cultivars is a viable alternative for controlling red rice in cultivated rice crops. The objective of this study was to evaluate the behavior of F2 hybrid population derivates of crossing between ammonium glufosinate - resistant GM rice and red rice. The F2 hybrid population derivates of crossing between GM rice and red rice are viable but do not present any apparent competitive advantage over red rice. The morphological characteristics of the F2 hybrid populations, such as tillering capacity, number of leaves produced and average plant height were partly reduced and partly unaffected by the introgression of the bar gene. The period between rice planting and 50% flowering increased in the red rice x GM rice F2 hybrids, compared to the parental red rice and GM rice. Average seed shattering rate in the four hybrid families was lower than in the red rice ecotypes, with such aspect also being unfavorable to the persistence of red rice in the environment. Seed dormancy of the hybrids was similar to that of the red rice ecotypes. However, management practices should be adopted to avoid crossing between transgenic rice and red rice.

  13. Maintaining or Abandoning African Rice: Lessons for Understanding Processes of Seed Innovation

    NARCIS (Netherlands)

    Teeken, B.W.E.; Nuijten, H.A.C.P.; Temudo, M.P.; Okry, F.; Mokuwa, G.A.; Struik, P.C.; Richards, P.

    2012-01-01

    Rice breeding and crop research predominantly emphasize adaptation to ecological conditions. Based on qualitative and quantitative research conducted between 2000 and 2012 we show how ecological factors, combined with socioeconomic variables, cultural norms and values, shape the use and development

  14. PRODUCTION OF HYBRID SEEDS OF THE VEGETABLE MARROW AT FREE POLLINATION

    Directory of Open Access Journals (Sweden)

    S. V. Kuzmin

    2018-01-01

    Full Text Available The purpose of this work performed in 2015-2017 on seedgrowing crops of the Crimean OSS VIR was receiving hybrid seeds of a vegetable marrow at free pollination and check of their quality by method of soil control. At laying of seed-growing crops, carrying out variety cleanings,, inspections and approbation were guided by the Instruction for approbation of seedgrowing crops of vegetable, melon cultures, fodder root crops and fodder cabbage (2008. The vegetable marrow with a high saturation pistillate flowers of Bl12, Su4 and Ar3 were used as maternal lines. Double processing by solution of an etrel was carried out to early phases of development of plants them. Use of this growth regulator has influenced blossoming of plants - in the lower knots men's flowers weren't formed, purely women's blossoming for the term of 14-17 days, sufficient for setting of seed fruits was observed. Control of blossoming of maternal forms was exercised by systematic inspections of plants on a floor. We have conducted three multiple examination. The first - before blossoming of maternal plants, in a budding phase when it is already possible to distinguish a sex of flowers, the second – in a phase of the beginning of blossoming. The third examination was conducted for definition of the beginning of blossoming of male flowers on plants of the maternal line. Timely carrying out inspections and variety cleanings, promotes receiving qualitative hybrid material. When carrying out soil control the high hybridism of seed material is revealed: F1 Bl12 x D1 - 95,3 %; F1 Su4 x D1 - 95,7 %; F1 Ar3 x D1 - 96,0 %. The results indicate that of the carried-out work, at free pollination of maternal and fatherly forms, vegetable marrow seeds with a high hybridism are received. Conducting the trial testing of new hybrids showed their high economic value. In comparison with the standard of Belogor F1, their total yield is higher by 16.7-25.7%, and the early yield by 10.5-27.7%. The

  15. OMNI: An optoelectronic multichannel network interface based on hybrid CMOS-SEED technology

    Science.gov (United States)

    Pinkston, Timothy M.

    1996-11-01

    This paper presents a hybrid CMOS-SEED multiprocessor network interface smart pixel design that implements a reservation-based channel control protocol for collisionless concurrent access to multiple optical interprocessor communication channels. An asynchronous optical token is used as the arbitration mechanism for reservation control instead of slotted access. This work demonstrates that complex network protocol functions can be implemented using optoelectronic smart pixel technology.

  16. Pollen Morphology and Viability Relates to Seed Production in Hybrid Roses

    Directory of Open Access Journals (Sweden)

    Nadeem Muhammad

    2014-10-01

    Full Text Available Fertility of hybrid tea roses is often reduced due to their interspesific origin but also to intensive inbreeding. New genotypes used as pollen donors represent an economic risk for a breeding program, as their influence on seed production is unknown. In this study 9 garden rose genotypes were selected from a company database as high fertile or low fertile male parents, according to the number of seeds per hybridization. Pollen morphology and in vitro germination of the selected genotypes were characterized. Pollen was either small (mean diameter = 30 urn, shrunken, and irregular (abnormal, or large (mean diameter = 30 urn, elliptical and crossed by furrows (normal. High correlations were found between the number of seeds produced per hybridization and the pollen diameter (r = 0.94 or the percentage of normal pollen (r = 0.96. In order to evaluate the predictive power of the models, we conducted regression analyses and performed a validation experiment on genotypes not present in the database and without background information on fertility. Pollen diameter and percentage of normal pollen were characterized and fitted in the regression models for seed set predictions. Validation with an independent dataset gave a good prediction for 83.3% of the data. This indicates that using either the mean pollen diameter or the percentage of normal pollen resulted in effective fertility prediction. Moreover cluster analysis of the data classified all the cultivars into various groups with varying fertility. This tool could enhance the genetic variability in crossings between hybrid tea roses, thus creating possibilities for less economically risky exploitation of new tetraploid genotypes as male parents.

  17. Do Hybrid Trees Inherit Invasive Characteristics? Fruits of Corymbia torelliana X C. citriodora Hybrids and Potential for Seed Dispersal by Bees.

    Science.gov (United States)

    Wallace, Helen Margaret; Leonhardt, Sara Diana

    2015-01-01

    Tree invasions have substantial impacts on biodiversity and ecosystem functioning, and trees that are dispersed by animals are more likely to become invasive. In addition, hybridisation between plants is well documented as a source of new weeds, as hybrids gain new characteristics that allow them to become invasive. Corymbia torelliana is an invasive tree with an unusual animal dispersal mechanism: seed dispersal by stingless bees, that hybridizes readily with other species. We examined hybrids between C. torelliana and C. citriodora subsp. citriodora to determine whether hybrids have inherited the seed dispersal characteristics of C. torelliana that allow bee dispersal. Some hybrid fruits displayed the characteristic hollowness, resin production and resin chemistry associated with seed dispersal by bees. However, we did not observe bees foraging on any hybrid fruits until they had been damaged. We conclude that C. torelliana and C. citriodora subsp. citriodora hybrids can inherit some fruit characters that are associated with dispersal by bees, but we did not find a hybrid with the complete set of characters that would enable bee dispersal. However, around 20,000 hybrids have been planted in Australia, and ongoing monitoring is necessary to identify any hybrids that may become invasive.

  18. Breeding of a new early season indica rice variety Ganzaoxian 56 by irradiation, anther culture and hybridization

    International Nuclear Information System (INIS)

    Huang Yingjin; Liu Yibai; Kuang Huiyun; Xu Zhengjin

    2005-01-01

    Ganzaoxian 56 is a new early season indica rice variety, which was bred in the College of Agronomy of Jiangxi Agricultural University by the integrative breeding techniques of radiation, anther culture and hybridization. Its main characteristics were as follows: super quality, high yield, high tolerance to heat-forced maturity, suitable maturity and high resistance to rice blast. It was registered by Crop Cultivar Registration Committee of Jiangxi Province on March 19, 2004. The breeding process of Ganzaoxian 56, main characteristics and the value of its exploitation and application were described in this paper. (authors)

  19. Protein disulfide isomerase-like protein 1-1 controls endosperm development through regulation of the amount and composition of seed proteins in rice.

    Directory of Open Access Journals (Sweden)

    Yeon Jeong Kim

    Full Text Available Protein disulfide isomerase (PDI is a chaperone protein involved in oxidative protein folding by acting as a catalyst and assisting folding in the endoplasmic reticulum (ER. A genome database search showed that rice contains 19 PDI-like genes. However, their functions are not clearly identified. This paper shows possible functions of rice PDI-like protein 1-1 (PDIL1-1 during seed development. Seeds of the T-DNA insertion PDIL1-1 mutant, PDIL1-1Δ, identified by genomic DNA PCR and western blot analysis, display a chalky phenotype and a thick aleurone layer. Protein content per seed was significantly lower and free sugar content higher in PDIL1-1Δ mutant seeds than in the wild type. Proteomic analysis of PDIL1-1Δ mutant seeds showed that PDIL1-1 is post-translationally regulated, and its loss causes accumulation of many types of seed proteins including glucose/starch metabolism- and ROS (reactive oxygen species scavenging-related proteins. In addition, PDIL1-1 strongly interacts with the cysteine protease OsCP1. Our data indicate that the opaque phenotype of PDIL1-1Δ mutant seeds results from production of irregular starch granules and protein body through loss of regulatory activity for various proteins involved in the synthesis of seed components.

  20. Soil-to-Rice Seeds Transfer Factors of Radioiodine and Technetium for Paddy Fields around the Radioactive-Waste Disposal Site in Gyeongju

    International Nuclear Information System (INIS)

    Choi, Yong Ho; Lim, Kwang Muk; Jun, In; Park, Doo Won; Keum, Dong Kwon; Han, Moon Hee

    2010-01-01

    Radiotracer experiments were performed over two years using pot cultures in a greenhouse to investigate soil-torice seeds transfer factors of radioiodine and technetium for paddy fields around the radioactive-waste disposal site in Gyeongju. Before transplanting rice seedlings, the top about 20 cm soils were thoroughly mixed with 125 I (2007) and 99 Tc (2008), and the pots were irrigated to simulate flooded rice fields. Transfer factors were determined as the ratios of the radionuclide concentrations in dry rice seeds (brown rice) to those in dry soils. Transfer factors of radioiodine and technetium were in the ranges of 1.1 x 10 -3 ∼ 6.4 x 10 -3 (three soils) and 5.4 x 10 -4 ∼ 2.5 x 10 -3 (four soils), respectively, for different soils. It seems that the differences in the clay content among soils played a more important role for such variations than those in the organic matter content and pH. As the representative values of radioiodine and technetium transfer factors for rice seeds, 2.9 x 10 -3 and 1.1 x 10 -3 , respectively, were proposed. In order to obtain more highly representative values in the future, investigations for the sites of interest need to be carried out continuously

  1. Disruption of endosperm development is a major cause of hybrid seed inviability between Mimulus guttatus and Mimulus nudatus.

    Science.gov (United States)

    Oneal, Elen; Willis, John H; Franks, Robert G

    2016-05-01

    Divergence of developmental mechanisms within populations could lead to hybrid developmental failure, and might be a factor driving speciation in angiosperms. We investigate patterns of endosperm and embryo development in Mimulus guttatus and the closely related, serpentine endemic Mimulus nudatus, and compare them to those of reciprocal hybrid seed. We address whether disruption in hybrid seed development is the primary source of reproductive isolation between these sympatric taxa. M. guttatus and M. nudatus differ in the pattern and timing of endosperm and embryo development. Some hybrid seeds exhibit early disruption of endosperm development and are completely inviable, while others develop relatively normally at first, but later exhibit impaired endosperm proliferation and low germination success. These developmental patterns are reflected in mature hybrid seeds, which are either small and flat (indicating little to no endosperm) or shriveled (indicating reduced endosperm volume). Hybrid seed inviability forms a potent reproductive barrier between M. guttatus and M. nudatus. We shed light on the extent of developmental variation between closely related species within the M. guttatus species complex, an important ecological model system, and provide a partial mechanism for the hybrid barrier between M. guttatus and M. nudatus. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  2. African rice (Oryza glaberrima) cultivation in the Togo Hills: ecological and socio-cultural cues in farmer seed selection and development

    NARCIS (Netherlands)

    Teeken, B.W.E.

    2015-01-01

    Abstract

    Teeken B (2015). African rice (Oryza glaberrima) cultivation in the Togo Hills: ecological and socio-cultural cues in farmer seed selection and development. PhD thesis, Wageningen University, The Netherlands, 306 pp. The low adoption rates of

  3. The Hybridization Barrier between Herbaceous Medicago sativa and Woody M. arborea Is Weakened by Selection of Seed Parents

    Science.gov (United States)

    Bingham, Edwin; Armour, David; Irwin, John

    2013-01-01

    Medicago sativa, alfalfa or lucerne, and M. arborea were considered reproductively isolated until recently. Then, in 2003, an alfalfa genotype was identified that produced a few seeds and progeny with hybrid traits after a large number of pollinations by M. arborea. A derivative of this alfalfa genotype also produced a low frequency of progeny with hybrid traits. Thus, the hybridization barrier was weakened by selection of seed parents. Hybrids from both events expressed traits from M. arborea and M. arborea-specific DNA bands, although more of the M. sativa genome was retained, based on the DNA results. Thus, there was chromatin elimination during embryogenesis, resulting in partial hybrids (hereafter hybrids). However, more than 30 hybrids with an array of M. arborea traits have been obtained thus far, and research continues on the nature of the hybrids. Traits have been genetically transmitted in crosses, and selected traits are in use for alfalfa breeding. This paper reviews the first hybrids and then focuses on further weakening of the hybridization barrier with the discovery of a more efficient hybridizer derived from crossing Medicago sativa subspecies, sativa, coerulea and falcata. This genotype was found to have reproductive abnormalities associated with its complex subspecies origin that are best described as hybrid breakdown. In effect, this subspecies derivative is a bridge-cross parent that consistently produces hybrids. Reproductive abnormalities in the bridge-cross parent are reported and discussed. PMID:27137379

  4. The Hybridization Barrier between Herbaceous Medicago sativa and Woody M. arborea Is Weakened by Selection of Seed Parents

    Directory of Open Access Journals (Sweden)

    Edwin Bingham

    2013-05-01

    Full Text Available Medicago sativa, alfalfa or lucerne, and M. arborea were considered reproductively isolated until recently. Then, in 2003, an alfalfa genotype was identified that produced a few seeds and progeny with hybrid traits after a large number of pollinations by M. arborea. A derivative of this alfalfa genotype also produced a low frequency of progeny with hybrid traits. Thus, the hybridization barrier was weakened by selection of seed parents. Hybrids from both events expressed traits from M. arborea and M. arborea-specific DNA bands, although more of the M. sativa genome was retained, based on the DNA results. Thus, there was chromatin elimination during embryogenesis, resulting in partial hybrids (hereafter hybrids. However, more than 30 hybrids with an array of M. arborea traits have been obtained thus far, and research continues on the nature of the hybrids. Traits have been genetically transmitted in crosses, and selected traits are in use for alfalfa breeding. This paper reviews the first hybrids and then focuses on further weakening of the hybridization barrier with the discovery of a more efficient hybridizer derived from crossing Medicago sativa subspecies, sativa, coerulea and falcata. This genotype was found to have reproductive abnormalities associated with its complex subspecies origin that are best described as hybrid breakdown. In effect, this subspecies derivative is a bridge-cross parent that consistently produces hybrids. Reproductive abnormalities in the bridge-cross parent are reported and discussed.

  5. Evidence for the emergence of new rice types of interspecific hybrid origin in West African farmers' fields.

    Directory of Open Access Journals (Sweden)

    Edwin Nuijten

    2009-10-01

    Full Text Available In West Africa two rice species (Oryza glaberrima Steud. and Oryza sativa L. co-exist. Although originally it was thought that interspecific hybridization is impossible without biotechnological methods, progenies of hybridization appear to occur in farmer fields. AFLP analysis was used to assess genetic diversity in West Africa (including the countries The Gambia, Senegal, Guinea Bissau, Guinea Conakry, Sierra Leone, Ghana and Togo using 315 rice samples morphologically classified prior to analysis. We show evidence for farmer interspecific hybrids of African and Asian rice, resulting in a group of novel genotypes, and identify possible mechanisms for in-field hybridization. Spontaneous back-crossing events play a crucial role, resulting in different groups of genetic diversity in different regions developed by natural and cultural selection, often under adverse conditions. These new groups of genotypes may have potential relevance for exploitation by plant breeders. Future advances in crop development could be achieved through co-operation between scientists and marginalized farmer groups in order to address challenges of rapid adaptation in a world of increasing socio-political and climatic uncertainty.

  6. Effect of seed treatment with static magnetic field (SMF) and low dose gamma radiation (GR) on grain yield of aerobic rice

    International Nuclear Information System (INIS)

    Kumar, Dinesh; Anand, Anjali; Singh, Bhupinder

    2014-01-01

    Aerobic rice cultivation is gaining popularity as it demands less water. However, poor germination of rice is an important issue in this situation. Seed pretreatment with static magnetic field (SMF) and gamma radiation (GR) at prescribed dose is known to influence the germination, seedling vigour and and yield of many crops. There is a possibility to improve the crop establishment under aerobic situation by physical seed treatment with static-magnetic field (SMF) and gamma radiation (GR) prior to sowing. Hence, a field experiment was conducted at the Indian Agricultural Research Institute, New Delhi during kharif 2012 and 2013 to study the effect of SMF and GR-treated seeds on growth and yield of aerobic rice. The five seed treatments were: SMF 50 mT for 2 hrs, SMF 100 mT for 2 hrs, GR 0.0025 kGy, GR 0.10 kGy and an untreated control. The experiment was laid out in a Randomized Block Design with four replications. Crop (variety 'Pusa Basmati-1121') was direct seeded on 25 th and 24 th June during 2012 and 2013, respectively at a spacing of 25 cm. Treatments GR 0.0025 kGy, SMF (50 mT) and SMF (100 mT) resulted in a significant improvement in grain yield of rice over control and GR dose (0.10 kGy) during both the years. Averaged across two years the grain yield increase by treating the rice seeds with GR 0.0025 kGy, SMF (50 mT) and SMF (100 mT) was 20.1, 17.6 and 14.5%, respectively over the control. Increase in GR dose (0.10 kGy ) was not effective in improving the yield, and was found to be similar to control. It is therefore concluded that treatment of rice seeds either with GR (0.0025 kGy) or SMF (50 mT) holds a great promise in increasing the grain yield of aerobic rice. (author)

  7. Genetic divergence among interspecific Paspalum hybrids based on seed production traits

    Directory of Open Access Journals (Sweden)

    Rodrigo Ramos Lopes

    Full Text Available ABSTRACT The use of genetic divergence as a basis for identifying superior individuals, with greater heterozygosity, is important in view of the difficulty when selecting of dissimilar genotypes exhibiting high average for interest traits. The aim of this study was to evaluate the genetic divergence and the expression of seed production traits in seventeen apomictic Paspalum plicatulum × Paspalum guenoarum hybrids and two male parents (P. guenoarum. A randomized block design was used, with genotypes individually arranged into ten blocks. The following traits were assessed: total number of tillers/plant (TT, reproductive tiller/plant (RT, number of racemes per inflorescence (NRI, reproductive tiller height (RTH, inflorescence rachis length (IRL, number of seeds/inflorescence (NSI, weight of a thousand seeds (WTS and seed production (SP. Genetic divergence among the genotypes was estimated using the Tocher method and UPGMA clustering, based on the generalized Mahalanobis distance (D2 ii’. The Tocher and UPGMA optimization methods showed high concordance. The traits that most contributed to genetic divergence were RTH (23.59%, IRL (21.63%, WTS (16.67% and SP (14.23%. The presence of genetic diversity made it possible to identify divergent genotypes and those with high means for the traits studied, allowing the selection of genotypes with significant breeding potential. Repeated cross-breeding of female superior plants with the genotypes Azulão and H20 can result in a high heterosis effect on seed production characteristics.

  8. [Inheritance of bc1 gene in intersubspecific hybrids of rice (Oryza sativa L.)].

    Science.gov (United States)

    Lü, Chuan-Gen; Zong, Shou-Yu; Zhao, Ling; Qi, Qing-Ming; Zou, Jiang-Shi; Ikehashi, Hiroshi

    2004-10-01

    Distorted segregation of the brittle culm-1 gene (bc1) on rice chromosome 3 was found with greatly increased or decreased frequency of bc1 bc1 genotype in inter-subspecific hybrids, although the gene normally transmitted to its offspring following the Mendelian Law in intra-subspecific hybrids. In a combination of Kamairazu//Ketan Nangka/Kamairazu,an increased frequency of bc1 bc1 in F1, normal segregation in F2, and increased and decreased frequency in a few F3 and F4 lines were observed. In a cross of IR36/Kamairazu, decreased frequency in F2, both normal and decreased segregations in F3 and F4, and a few lines of increased ratio in F4 were found. In F2 of Ketan Nangka/IR36//Kamairazu, increased and decreased and normal segregations were all observed. There was no significant correlation between the frequency of bc1 bc1 and pollen fertility. It implied that distorted segregation of bc1 was caused by selective fertilization of male gametes, which were governed by gametophyte genes of ga2, ga3 and ga14 on chromosome 3.

  9. Development of Selectable Marker-Free Transgenic Rice Plants with Enhanced Seed Tocopherol Content through FLP/FRT-Mediated Spontaneous Auto-Excision.

    Directory of Open Access Journals (Sweden)

    Hee-Jong Woo

    Full Text Available Development of marker-free transgenic plants is a technical alternative for avoiding concerns about the safety of selectable marker genes used in genetically modified (GM crops. Here, we describe the construction of a spontaneous self-excision binary vector using an oxidative stress-inducible modified FLP/FRT system and its successful application to produce marker-free transgenic rice plants with enhanced seed tocopherol content. To generate selectable marker-free transgenic rice plants, we constructed a binary vector using the hpt selectable marker gene and the rice codon-optimized FLP (mFLP gene under the control of an oxidative stress-inducible promoter between two FRT sites, along with multiple cloning sites for convenient cloning of genes of interest. Using this pCMF binary vector with the NtTC gene, marker-free T1 transgenic rice plants expressing NtTC were produced by Agrobacterium-mediated stable transformation using hygromycin as a selective agent, followed by segregation of selectable marker genes. Furthermore, α-, γ-, and total tocopherol levels were significantly increased in seeds of the marker-free transgenic TC line compared with those of wild-type plants. Thus, this spontaneous auto-excision system, incorporating an oxidative stress-inducible mFLP/FRT system to eliminate the selectable marker gene, can be easily adopted and used to efficiently generate marker-free transgenic rice plants. Moreover, nutritional enhancement of rice seeds through elevation of tocopherol content coupled with this marker-free strategy may improve human health and public acceptance of GM rice.

  10. Development of Selectable Marker-Free Transgenic Rice Plants with Enhanced Seed Tocopherol Content through FLP/FRT-Mediated Spontaneous Auto-Excision.

    Science.gov (United States)

    Woo, Hee-Jong; Qin, Yang; Park, Soo-Yun; Park, Soon Ki; Cho, Yong-Gu; Shin, Kong-Sik; Lim, Myung-Ho; Cho, Hyun-Suk

    2015-01-01

    Development of marker-free transgenic plants is a technical alternative for avoiding concerns about the safety of selectable marker genes used in genetically modified (GM) crops. Here, we describe the construction of a spontaneous self-excision binary vector using an oxidative stress-inducible modified FLP/FRT system and its successful application to produce marker-free transgenic rice plants with enhanced seed tocopherol content. To generate selectable marker-free transgenic rice plants, we constructed a binary vector using the hpt selectable marker gene and the rice codon-optimized FLP (mFLP) gene under the control of an oxidative stress-inducible promoter between two FRT sites, along with multiple cloning sites for convenient cloning of genes of interest. Using this pCMF binary vector with the NtTC gene, marker-free T1 transgenic rice plants expressing NtTC were produced by Agrobacterium-mediated stable transformation using hygromycin as a selective agent, followed by segregation of selectable marker genes. Furthermore, α-, γ-, and total tocopherol levels were significantly increased in seeds of the marker-free transgenic TC line compared with those of wild-type plants. Thus, this spontaneous auto-excision system, incorporating an oxidative stress-inducible mFLP/FRT system to eliminate the selectable marker gene, can be easily adopted and used to efficiently generate marker-free transgenic rice plants. Moreover, nutritional enhancement of rice seeds through elevation of tocopherol content coupled with this marker-free strategy may improve human health and public acceptance of GM rice.

  11. The Mitochondrion-Located Protein OsB12D1 Enhances Flooding Tolerance during Seed Germination and Early Seedling Growth in Rice

    Directory of Open Access Journals (Sweden)

    Dongli He

    2014-07-01

    Full Text Available B12D belongs to a function unknown subgroup of the Balem (Barley aleurone and embryo proteins. In our previous work on rice seed germination, we identified a B12D-like protein encoded by LOC_Os7g41350 (named OsB12D1. OsB12D1 pertains to an ancient protein family with an amino acid sequence highly conserved from moss to angiosperms. Among the six OsB12Ds, OsB12D1 is one of the major transcripts and is primarily expressed in germinating seed and root. Bioinformatics analyses indicated that OsB12D1 is an anoxic or submergence resistance-related gene. RT-PCR results showed OsB12D1 is induced remarkably in the coleoptiles or roots by flooding during seed germination and early seedling growth. The OsB12D1-overexpressed rice seeds could protrude radicles in 8 cm deep water, further exhibiting significant flooding tolerance compared to the wild type. Moreover, this tolerance was not affected by the gibberellin biosynthesis inhibitor paclobutrazol. OsB12D1 was identified in the mitochondrion by subcellular localization analysis and possibly enhances electron transport through mediating Fe and oxygen availability under flooded conditions. This work indicated that OsB12D1 is a promising gene that can help to enhance rice seedling establishment in farming practices, especially for direct seeding.

  12. Comportamento de hidratação e qualidade fisiológica das sementes de arroz Hidration performance and physiological quality of rice seeds

    Directory of Open Access Journals (Sweden)

    Rafael Pivotto Bortolotto

    2008-12-01

    Full Text Available O trabalho teve como objetivo verificar a relação existente entre o comportamento da curva de hidratação de sementes de arroz e sua qualidade fisiológica. Foram utilizados seis lotes de sementes de arroz, sendo três da cultivar IRGA 417 e três da cultivar IRGA 422 CL, inicialmente submetidos a testes para caracterizar o potencial fisiológico dos lotes: germinação, primeira contagem de germinação, envelhecimento acelerado, frio sem terra, condutividade elétrica, comprimento de plântula, massa seca de plântula e emergência em campo. Posteriormente, foi determinada a curva de hidratação das sementes de cada lote. Conclui-se que a qualidade fisiológica afeta o teor de água alcançado pelas sementes de arroz durante a hidratação, e nas sementes menos vigorosas notam-se menor velocidade de hidratação e grau de umidade, comparativamente às sementes de mais vigor.The objective of this study was to verify the relationship between the shape of the hydration curve and the physiological quality of rice seeds. Six lots of rice seeds were used, three of cultivar IRGA 417 and three of cultivar IRGA 422 CL. The rice seeds were submitted to a set of tests in order to measure the physiological potential of the lots: germination, first count germination, accelerated aging, cold test (without soil, electrical conductivity, length and dry mass of seedlings and seedling emergence in the field. After evaluation of the initial quality of the lots, the hydration curve was determined. It was concluded that physiological quality affects the water content reached by rice seeds during hydration, and that seeds with lower vigor present lower hydration rate and water content when compared to seeds with higher vigor.

  13. Weed management through herbicide application in direct-seeded rice and yield modeling by artificial neural network

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, D.; Singh, U.P.; Ray, K.; Das, A.

    2016-11-01

    In direct seeded rice (DSR) cultivation, weed is the major constraint mainly due to absence of puddling in field. The yield loss due to weed interference is huge, may be up to 100%. In this perspective, the present experiment was conducted to study the efficacy of selected herbicides, and to predict the rice yield using artificial neural network (ANN) models. The dry weight and density of weeds were recorded at different growth stages and consequently herbicidal efficacy was evaluated. Experimental results revealed that pre-emergence (PRE) herbicide effectively controlled the germination of grassy weeds. Application bispyribac-sodium as post-emergence (POST) following PRE herbicides (clomazone or pendimethalin) or as tank-mixture with clomazone effectively reduced the density and biomass accumulation of diverse weed flora in DSR. Herbicidal treatments improved the plant height, yield attributes and grain yield (2.7 to 5.5 times) over weedy check. The sensitivity of the best ANN model clearly depicts that the weed control index (WCI) of herbicides was most important than their weed control efficiency (WCE). Besides, the early control of weeds is a better prescription to improve rice yield. Differences in sensitivity values of WCI and WCE across the crop growth stages also suggest that at 15, 30 and 60 days after sowing, herbicides most effectively controlled sedges, broad leaves and grasses, respectively. Based on the grain yield and herbicidal WCE, it can be concluded that the combined application of pendimethalin or clomazone as PRE followed by bispyribac-sodium as POST or tank-mixture of clomazone + bispyribac sodium can effectively control different weed flushes throughout the crop growth period in DSR. (Author)

  14. Effect of Neem Seed Kernel Extracts in the Management of Rice ...

    African Journals Online (AJOL)

    user

    Rice plant is an ideal host for a large number of insect pests in ... For farmers and researchers alike reducing the numbers of these pests is therefore a priority. In the ..... Development of a rational control system against insect ... Integration of some biopesticides and trichogramma chilonis for the sustainable management of.

  15. Effect of Cyanobacteria Isolates on Rice Seeds Germination in Saline Soil

    Directory of Open Access Journals (Sweden)

    Mostafa M. El -Sheekh

    2018-03-01

    Full Text Available Cyanobacteria are prokaryotic photosynthetic communities which are used in biofertilization of many plants especially rice plant. Cyanobacteria play a vital role to increase the plant's ability for salinity tolerance. Salinity is a worldwide problem which affects the growth and productivity of crops. In this work three cyanobacteria strains (Nostoc calcicola, Anabaena variabilis, and Nostoc linkia were isolated from saline soil at Kafr El-Sheikh Governorate; North Egypt. The propagated cyanobacteria strains were used to withstand salinity of the soil and increase rice plant growth (Giza 178. The length of roots and shoot seedlings was measured for seven and forty days of cultivation, respectively. The results of this investigation showed that the inoculation with Nostoc calcicola, Anabaena variabilis, and Nostoc linkia increased root length by 27.0, 4.0, 3.0 % and 39, 20, 19 % in EC5 and 10 (ds/m, respectively. Similarly, they increased shoot length by 121, 70, 55 %, 116, 88, 82 % in EC5 and 10 (ds/m, respectively. In EC15and more concentrations, control rice plants could not grow while those to which cyanobacteria were inoculated could withstand only EC15 but not other elevated concentrations. These results encourage using Nostoc calcicola,Anabaena variabilis, and Nostoc linkia as biofertilizer for rice plant in the saline soil for increasing growth and decrease soil electrical conductivity.

  16. Seed storage protein polymorphism in ten elite rice (Oryza sativa L ...

    African Journals Online (AJOL)

    user

    2011-02-14

    Feb 14, 2011 ... for several economical traits by conserving landrace genotypes and ... plasm, seed storage protein analysis represents a valid alternative ... of each variety was taken and ground into fine powder using pestle and mortal and ...

  17. Hybridization study of wild rice Oryza glumaepatula with varieties of cultivated rice (O. sativa) and wild (O. grandiglumis)

    International Nuclear Information System (INIS)

    Villalobos Cascante, Eddier

    2015-01-01

    The process of interspecific hybridization of the wild species O. glumaepatula is studied with commercial varieties of the species O. sativa and O. grandiglumis, by morphological evaluation and hybrid flow cytometry. Hybrid plants were evaluated of cross between O. glumaepatula, located in the wetlands of Rio Medio Queso and two varieties of O. sativa, Puita Inta and CFX 18 resistant to a herbicide. The technique of Polymerase Chain Reaction Allele Specifies Oligonucleotide (PCR-ASO) was used to detect allelic mutations in the ALS gene conferring herbicide resistance, and it is confirmed the hybrid nature of the plants obtained at crossings. 68 hybrids were obtained: O. glumaepatula x P. Inta, 21 hybrids P. Inta x O. glumaepatula, 4 hybrids O. glumaepatula x CFX-18 and 15 hybrids CFX-18 x O. glumaepatula. 10 morphological descriptors of the genus Oryza were evaluated and determined that are indifferent to the direction and type of crossing, the hybrids resemble to the wild species O. glumaepatula for characters: height, panicle length and ligule length. All hybrids have showed similarity to commercial varieties in flag leaf length. Other characters evaluated in the hybrids have presented maternal effect, heterosis and intermediate values. The protocol of flow cytometry (FCM) is standardized species for Oryza genus analyzing nuclear DNA content of 106 samples of leaf tissue of wild species O. glumaepatula, O. grandiglumis; whose average has been of 0.73 picograms, and natural hybrids product of the cross of these species. The result has been intermediate compared with O. grandiglumis and O. glumaepatula that have made available to 1.0 picograms and 0.50 of DNA respectively. The molecular nature of the hybrids was confirmed in this way. (author) [es

  18. Seed vigor classification using analysis of mean radicle emergence time and single counts of radicle emergence in rice (Oryza sativa L. and mung bean (Vigna radiata (L. Wilczek

    Directory of Open Access Journals (Sweden)

    Damrongvudhi Onwimol

    2016-09-01

    Full Text Available The radicle emergence (RE test for seed vigor classification is an ingenious protocol that will lead to a fast and reliable automated procedure for verifying seed quality using image analysis. Nevertheless, the success of this protocol has never been described in rice and mung bean that are global staple foods. This experiment analyzed the correlation between RE (2 mm in length and normal seedlings (NS during a germination test of rice and mung bean. In total, 12 samples using four cultivars of each species were obtained from different locations and production years. In addition to the germination test, an accelerated ageing (AA test and an electrical conductivity (EC test were analyzed. The results revealed that the pattern of the cumulative germination curve of RE and NS coincided but the curve for NS was longer than for RE (p ≤ 0.05. There was no significant difference in the variance of the germination time between RE and NS of rice but there was a significant difference for mung bean. The vigor levels of the rice seed classified by single counts of RE at 110 h after set to germinate (HASG conformed to the result of single counts of NS at 200 HASG and the result of the AA test. However, these classifications disagreed with the result derived from the EC test. In contrast, the mung bean vigor level classified by single counts of RE, NS, the AA test and the EC test did not relate well with each other. In conclusion, it is possible to develop the automated procedure for verifying rice seed quality using image analysis via a single count of RE.

  19. Embryo development and corresponding factors affecting in vitro germination of Cymbidium faberi × C. sinense hybrid seeds

    Directory of Open Access Journals (Sweden)

    Li Fengtong

    2016-01-01

    Full Text Available A better understanding of embryo development would provide insights into seed quality and subsequent germination events in the interspecific hybridization of Cymbidium faberi ‘Jiepeimei’ × C. sinense ‘Qijianheimo’. At the mature stage, 26.1% of the ovules were abnormal. Most of the hybrid embryos could develop normally. Abortions mainly occurred at the zygote (9.5% and 2-4-celled embryo (15.1% stages. No germination was observed at 90 and 105 days after pollination (DAP, when the embryo was at the early globular stage, with abundant organelles but no storage materials. During 110-130 DAP, the globular embryo was formed and the starch grains began to accumulate in plastids. The hybrid seeds collected at 120 DAP showed initiation of germination. Germination significantly increased at 135 DAP and was maximal at 150 DAP, during which period the hybrid embryos developed into the late globular stage. The storage materials, i.e. lipid and protein bodies, began to accumulate and the filamentary structures derived from suspensor cells still persisted. After the seeds matured (160 DAP, the germination percentage declined sharply. Safranin staining revealed that the outer seed coat was totally cuticularized and the inner seed coat appeared as a cuticle layer enclosing the embryo proper tightly, which may be the main factor inhibiting the subsequent germination of hybrid seeds. In conclusion, 150 DAP should be the opportune time for the in vitro germination of C. faberi ‘Jiepeimei’ × C. sinense ‘Qijianheimo’ hybrid seeds.

  20. Evolution of new rice varieties by induced mutations to increase yield and resistance to diseases and to improve seed quality

    International Nuclear Information System (INIS)

    Miah, A.J.; Bhatti, I.M.

    1968-01-01

    Seeds of two indica rice varieties namely, Kangni-27 (a coarse variety) and Dokri Basmati (a fine variety) were irradiated with 20, 25, 30, 35, 40, 45 and 50 kR of gamma rays from a 13,000-Ci 60 Co source. In the M 1 generation (1964), germination percentage, seedling height and seed fertility were studied. The data indicated that Kangni-27 is more radioresistant than Dokri Basmati. In the M 2 generation (1965) two polygenic traits, i.e. leaf size and grains per unit length were studied. From the analysis of the data it was found that variability was greater in the irradiated populations than in the non-irradiated controls. Apart from the study of the polygenic traits, several mutants which appeared to be useful to the breeder (e.g. dwarf, short-culm and early flowering) were isolated form the irradiated populations of Kangni-27. In the M 3 generation (1966) several agronomically important characters were studied in all the mutants isolated in the M 2 generation. It was noticed that the mean values of most of the characters of all the mutants deviated from the mean values of the respective controls. These deviations were both negative and positive. Further analysis is in progress. Three more experiments were started, two in the year 1965 on the effects of gamma rays and one in 1966 to compare the effects of EMS and gamma rays. (author). 31 refs, 3 figs, 6 tabs

  1. Differential gene expression in an elite hybrid rice cultivar (Oryza sativa, L and its parental lines based on SAGE data

    Directory of Open Access Journals (Sweden)

    Chen Chen

    2007-09-01

    Full Text Available Abstract Background It was proposed that differentially-expressed genes, aside from genetic variations affecting protein processing and functioning, between hybrid and its parents provide essential candidates for studying heterosis or hybrid vigor. Based our serial analysis of gene expression (SAGE data from an elite Chinese super-hybrid rice (LYP9 and its parental cultivars (93-11 and PA64s in three major tissue types (leaves, roots and panicles at different developmental stages, we analyzed the transcriptome and looked for candidate genes related to rice heterosis. Results By using an improved strategy of tag-to-gene mapping and two recently annotated genome assemblies (93-11 and PA64s, we identified 10,268 additional high-quality tags, reaching a grand total of 20,595 together with our previous result. We further detected 8.5% and 5.9% physically-mapped genes that are differentially-expressed among the triad (in at least one of the three stages with P-values less than 0.05 and 0.01, respectively. These genes distributed in 12 major gene expression patterns; among them, 406 up-regulated and 469 down-regulated genes (P Conclusion We improved tag-to-gene mapping strategy by combining information from transcript sequences and rice genome annotation, and obtained a more comprehensive view on genes that related to rice heterosis. The candidates for heterosis-related genes among different genotypes provided new avenue for exploring the molecular mechanism underlying heterosis.

  2. DNA synthesis time in germinating rice and pattern of diethylsulphate induced mutations in pre-soaked seeds

    International Nuclear Information System (INIS)

    Narahari, P.

    1978-01-01

    DNA synthesis pattern in germinating rice seeds, pre-soaked in water for varying periods upto 48 hr, was determined by following the pulse incorporation of 3 H-thymidine into the TCA-insoluble nucleoprotein. Synthesis of DNA commenced at 24 hr, progressively increased to a first peak at about 38 hr, thereafter showed a 1/3rd drop and subsequently increased to a 2nd and still higher peak at 46 to 48 hr of pre-soaking. Treatments of diethylsulphate (dES) at a low concentration (0.2%-2hr) administered at various progressing stages of DNA synthesis resulted in decrease in seedling height and survival, and increase in mutation frequency at 45 hr. pre-soaking, maximum mutation frequencies of 20, 10 and 2% on M 1 plants, M 1 spikes and M 2 seedling bases, respectively were observed. Higher dES concentration (0.3%-2hr) given at later periods of pre-soaking showed near lethal effects and consequently decreased mutation frequencies. Treatments of sodium fluoride given singly or in combination with dES did not show any substantially different results as compared to those of the respective controls. Mutation spectra observed after dES treatments to germinating seeds, at different pre-soaking periods, were quite dissimilar. Specific mutations of economic importance like semi-dwarf mutants were isolated from the treatment of germinating seeds pre-soaked for 37.5 hr or more when shoot apex cells were undergoing DNA synthesis. (author)

  3. The Organelle Genomes of Hassawi Rice (Oryza sativa L.) and Its Hybrid in Saudi Arabia: Genome Variation, Rearrangement, and Origins

    Science.gov (United States)

    Zhang, Tongwu; Hu, Songnian; Zhang, Guangyu; Pan, Linlin; Zhang, Xiaowei; Al-Mssallem, Ibrahim S.; Yu, Jun

    2012-01-01

    Hassawi rice (Oryza sativa L.) is a landrace adapted to the climate of Saudi Arabia, characterized by its strong resistance to soil salinity and drought. Using high quality sequencing reads extracted from raw data of a whole genome sequencing project, we assembled both chloroplast (cp) and mitochondrial (mt) genomes of the wild-type Hassawi rice (Hassawi-1) and its dwarf hybrid (Hassawi-2). We discovered 16 InDels (insertions and deletions) but no SNP (single nucleotide polymorphism) is present between the two Hassawi cp genomes. We identified 48 InDels and 26 SNPs in the two Hassawi mt genomes and a new type of sequence variation, termed reverse complementary variation (RCV) in the rice cp genomes. There are two and four RCVs identified in Hassawi-1 when compared to 93–11 (indica) and Nipponbare (japonica), respectively. Microsatellite sequence analysis showed there are more SSRs in the genic regions of both cp and mt genomes in the Hassawi rice than in the other rice varieties. There are also large repeats in the Hassawi mt genomes, with the longest length of 96,168 bp and 96,165 bp in Hassawi-1 and Hassawi-2, respectively. We believe that frequent DNA rearrangement in the Hassawi mt and cp genomes indicate ongoing dynamic processes to reach genetic stability under strong environmental pressures. Based on sequence variation analysis and the breeding history, we suggest that both Hassawi-1 and Hassawi-2 originated from the Indonesian variety Peta since genetic diversity between the two Hassawi cultivars is very low albeit an unknown historic origin of the wild-type Hassawi rice. PMID:22870184

  4. Ability of Arkansas LaKast and LaKast Hybrid Rice Bran to Reduce Salmonella Typhimurium in Chicken Cecal Incubations and Effects on Cecal Microbiota

    Directory of Open Access Journals (Sweden)

    Sun Ae Kim

    2018-02-01

    Full Text Available The objective of the present study was to evaluate the prebiotic ability of Arkansas (AR LaKast rice bran cultivars as a feed supplement to reduce Salmonella Typhimurium and other gut microbiota. An in vitro mixed anaerobic culture system was used to simulate conditions in the chicken ceca. Anaerobic cultures contained feed, cecal contents collected from 2, 4, and 6 weeks of chicken broilers, and with/without AR rice bran (pureline and hybrid. After 24 h pre-incubation, S. Typhimurium was inoculated into the anaerobic cultures and surviving S. Typhimurium were enumerated during anaerobic incubation up to 48 h. Samples were also collected after 0, 6, 12, 24, 48 h incubation for microbiome analysis with an Illumina MiSeq platform to investigate the changes in bacterial composition. Both pure and hybrid LaKast rice exhibited significant inhibitory effects in all experiments using 2, 4, and 6 weeks ceca but greater bactericidal effects by LaKast rice were observed at 6 weeks compared to 2- and 4-week ceca samples. For samples containing 6-week chicken ceca, the pureline and hybrid rice bran resulted in no viable S. Typhimurium and 6.58 log CFU/ml reduction after 48 h, respectively. Adding rice bran also led to changes in the cecal microbiota. LaKast rice bran resulted in more diverse bacterial population than control groups without any rice bran. The lowest abundance of Proteobacteria (at phylum level and Enterobacteriaceae (at family and genus level was exhibited in LaKast pure treated groups followed by LaKast hybrid and control. This may be attributed to a significant reduction of S. Typhimurium of the Enterobacteriaceae family and Proteobacteria phylum. This study suggests the beneficial functionality of LaKast rice brans as biological supplements in feed. The use of rice bran is favorable for both the consumer and the rice industry because of the perception of rice bran as a naturally occurring substance. As an abundant by-product of rice

  5. Vitamin E homologs and ¿-oryzanol levels in rice (Oryza sativa L.) during seed development

    Science.gov (United States)

    Vitamin E homologs (tocopherols and tocotrienols) and gamma-oryzanol have gained significant attention due to their proposed health benefits and ability to increase vegetable oil stability. Changes in the levels of these phytochemicals were examined during seed development. Rapid accumulation of toc...

  6. Biogenic synthesis, characterization of silver nanoparticles using multani mitti (fullers earth), tomato (solanum lycopersicum) seeds, rice husk (oryza sativa) and evaluation of their potential antimicrobial activity

    International Nuclear Information System (INIS)

    Dar, P.; Hina, A.; Anwar, J.

    2016-01-01

    The synthesis of silver nanoparticles of three different biogenic materials Multani mitti (Fullers earth), Tomato (Solanum lycopersicum) seeds, Rice Husk (Oryza sativa) was carried out. The possible presence and variability of comprehensive biomolecules in these materials turned as capping and reducing agents which optimize the reduction rate and stabilization of silver nanoparticles. Characterizations were determined by using ultraviolet-visible (UV-Vis) spectroscopy, Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Stable silver nanoparticles of average size 4.6, 41.1 and 10.6 nm were obtained for Multani mitti, tomato seeds and rice husk respectively. Phenolic and carboxylic biomolecules were identified as active reducing agents of Ag+2 to Ag0. The antimicrobial activity was carried out against Klebsiella pneumonia, Salmonella enterica, Escherichia coli and Staphylococcus aureus strains by using well diffusion method. Maximum zone of inhibition (ZOI) was found against Staphylococcus aureus by all of the three biogenic materials. (author)

  7. Simultaneous Detection of Three Bacterial Seed-Borne Diseases in Rice Using Multiplex Polymerase Chain Reaction

    OpenAIRE

    Kang, In Jeong; Kang, Mi-Hyung; Noh, Tae-Hwan; Shim, Hyeong Kwon; Shin, Dong Bum; Heu, Suggi

    2016-01-01

    Burkholderia glumae (bacterial grain rot), Xanthomonas oryzae pv. oryzae (bacterial leaf blight), and Acidovorax avenae subsp. avenae (bacterial brown stripe) are major seedborne pathogens of rice. Based on the 16S and 23S rDNA sequences for A. avenae subsp. avenae and B. glumae, and transposase A gene sequence for X. oryzae pv. oryzae, three sets of primers had been designed to produce 402 bp for B. glumae, 490 bp for X. oryzae, and 290 bp for A. avenae subsp. avenae with the 63°C as an opti...

  8. Effects of Rice Bran, Flax Seed, and Sunflower Seed on Growth Performance, Carcass Characteristics, Fatty Acid Composition, Free Amino Acid and Peptide Contents, and Sensory Evaluations of Native Korean Cattle (Hanwoo

    Directory of Open Access Journals (Sweden)

    Chang Bon Choi

    2016-02-01

    Full Text Available This study was conducted to evaluate the effect of dietary supplementation with rice bran, flax seed, or sunflower seed to finishing native Korean cattle (Hanwoo on growth performances, carcass characteristics, fatty acid composition, free amino acid and peptide contents, and sensory evaluations of Longissimus muscle (LM. A total of 39 Hanwoo steers (average age of 22.2 mo and average body weight (BW of 552.2 kg were randomly divided into Control, rice bran (RB, flax seed (FS, or Sunflower seed (SS groups. The steers were group fed for 273 d until they reached an average age of 31.2 mo. Final BW was 768.2, 785.8, 786.2, and 789.0 kg, and average daily gain was 0.79, 0.85, 0.82, and 0.84 kg for the Control, RS, FS, and SS groups, respectively (p>0.05. Fat thickness of the FS group (19.8 mm was greater (p0.05 scores for flavor, umami, and overall palatability in sensory evaluations. In conclusion, supplementation of flax seed to diets of finishing Hanwoo steers improved sensory evaluations which might have been caused by increases in flavor related amino acids such as methionine, glutamic acid and α-AAA and peptides, anserine and carnosine, and their complex reactions.

  9. The α-Amylase Induction in Endosperm during Rice Seed Germination Is Caused by Gibberellin Synthesized in Epithelium1

    Science.gov (United States)

    Kaneko, Miyuki; Itoh, Hironori; Ueguchi-Tanaka, Miyako; Ashikari, Motoyuki; Matsuoka, Makoto

    2002-01-01

    We recently isolated two genes (OsGA3ox1 and OsGA3ox2) from rice (Oryza sativa) encoding 3β-hydroxylase, which catalyzes the final step of active gibberellin (GA) biosynthesis (H. Itoh, M. Ueguchi-Tanaka, N. Sentoku, H. Kitano, M. Matsuoka, M. Kobayashi [2001] Proc Natl Acad Sci USA 98: 8909–8914). Using these cloned cDNAs, we analyzed the temporal and spatial expression patterns of the 3β-hydroxylase genes and also an α-amylase gene (RAmy1A) during rice seed germination to investigate the relationship between GA biosynthesis and α-amylase expression. Northern-blot analyses revealed that RAmy1A expression in the embryo occurs before the induction of 3β-hydroxylase expression, whereas in the endosperm, a high level of RAmy1A expression occurs 1 to 2 d after the peak of OsGA3ox2 expression and only in the absence of uniconazol. Based on the analysis of an OsGA3ox2 null mutant (d18-Akibare dwarf), we determined that 3β-hydroxylase produced by OsGA3ox2 is important for the induction of RAmy1A expression and that the OsGA3ox1 product is not essential for α-amylase induction. The expression of OsGA3ox2 was localized to the shoot region and epithelium of the embryo, strongly suggesting that active GA biosynthesis occurs in these two regions. The synthesis of active GA in the epithelium is important for α-amylase expression in the endosperm, because an embryonic mutant defective in shoot formation, but which developed epithelium cells, induced α-amylase expression in the endosperm, whereas a mutant defective in epithelium development did not. PMID:11950975

  10. Improvement of efficient in vitro regeneration potential of mature callus induced from Malaysian upland rice seed (Oryza sativa cv. Panderas).

    Science.gov (United States)

    Mohd Din, Abd Rahman Jabir; Iliyas Ahmad, Fauziah; Wagiran, Alina; Abd Samad, Azman; Rahmat, Zaidah; Sarmidi, Mohamad Roji

    2016-01-01

    A new and rapid protocol for optimum callus production and complete plant regeneration has been assessed in Malaysian upland rice (Oryza sativa) cv. Panderas. The effect of plant growth regulator (PGR) on the regeneration frequency of Malaysian upland rice (cv. Panderas) was investigated. Mature seeds were used as a starting material for callus induction experiment using various concentrations of 2,4-D and NAA. Optimal callus induction frequency at 90% was obtained on MS media containing 2,4-D (3 mg L(-1)) and NAA (2 mg L(-1)) after 6 weeks while no significant difference was seen on tryptophan and glutamine parameters. Embryogenic callus was recorded as compact, globular and light yellowish in color. The embryogenic callus morphology was further confirmed with scanning electron microscopy (SEM) analysis. For regeneration, induced calli were treated with various concentrations of Kin (0.5-1.5 mg L(-1)), BAP, NAA and 0.5 mg L(-1) of TDZ. The result showed that the maximum regeneration frequency (100%) was achieved on MS medium containing BAP (0.5 mg L(-1)), Kin (1.5 mg L(-1)), NAA (0.5 mg L(-1)) and TDZ (0.5 mg L(-1)) within four weeks. Developed shoots were successfully rooted on half strength MS free hormone medium and later transferred into a pot containing soil for acclimatization. This cutting-edge finding is unique over the other existing publishable data due to the good regeneration response by producing a large number of shoots.

  11. Effects of seed mixture sowing with resistant and susceptible rice on population dynamics of target planthoppers and non-target stemborers and leaffolders.

    Science.gov (United States)

    Li, Zhuo; Wan, Guijun; Wang, Long; Parajulee, Megha N; Zhao, Zihua; Chen, Fajun

    2018-07-01

    The widespread planting of insect-resistant crops has caused a dramatic shift in agricultural landscapes, thus raising concerns about the potential impact on both target and non-target pests worldwide. In this study, we examined the potential effects of six seed mixture ratios of insect-resistance dominance [100% (R100), 95% (S05R95), 90% (S10R90), 80% (S20R80), 60% (S40R60), and 0% (S100)] on target and non-target pests in a 2-year field trial in southern China. The occurrence of the target pests Nilaparvata lugens and Sogatella furcifera decreased with an increase in the ratio of resistant rice, and mixture ratios with ≥90% resistant rice significantly increased the pest suppression efficiency, with the lowest occurrences of the non-target pests Sesamia inferens, Chilo suppressalis and Cnaphalocrocis medinalis for S100 and S10R90 seed mixture ratios. Furthermore, there were no significant differences in the 1000-grain dry weight and grain yield between R100 and other treatments with ≥80% resistant seeds in the mixture (S20R80, S10R90 and S05R95). S10R90 produced a good yield and provided the most effective control of both target and non-target pests, with the potential to significantly reduce the application of chemical pesticides for integrated pest management in paddy fields. It is further presumed that the strategy of seed mixture with resistant and susceptible rice would be advantageous for rice yield stability. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  12. Cell wall targeted in planta iron accumulation enhances biomass conversion and seed iron concentration in Arabidopsis and rice

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Haibing [Center for Direct Catalytic Conversion Of Biomass to Biofuels (C3Bio), Purdue University, West Lafayette IN USA; Department of Horticulture, Purdue University, West Lafayette IN USA; Department of Biological Sciences, Purdue University, West Lafayette IN USA; Wei, Hui [Biosciences Center, National Renewable Energy Laboratory, Golden CO USA; Ma, Guojie [Center for Direct Catalytic Conversion Of Biomass to Biofuels (C3Bio), Purdue University, West Lafayette IN USA; Department of Horticulture, Purdue University, West Lafayette IN USA; Antunes, Mauricio S. [Center for Direct Catalytic Conversion Of Biomass to Biofuels (C3Bio), Purdue University, West Lafayette IN USA; Department of Biological Sciences, Purdue University, West Lafayette IN USA; Vogt, Stefan [X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne IL USA; Cox, Joseph [Center for Direct Catalytic Conversion Of Biomass to Biofuels (C3Bio), Purdue University, West Lafayette IN USA; Department of Horticulture, Purdue University, West Lafayette IN USA; Zhang, Xiao [Department of Horticulture, Purdue University, West Lafayette IN USA; Liu, Xiping [Center for Direct Catalytic Conversion Of Biomass to Biofuels (C3Bio), Purdue University, West Lafayette IN USA; Department of Horticulture, Purdue University, West Lafayette IN USA; Bu, Lintao [National Bioenergy Center, National Renewable Energy Laboratory, Golden CO USA; Gleber, S. Charlotte [X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne IL USA; Carpita, Nicholas C. [Department of Biological Sciences, Purdue University, West Lafayette IN USA; Department of Botany and Plant Pathology, Purdue University, West Lafayette IN USA; Makowski, Lee [Department of Bioengineering, Northeastern University, Boston MA USA; Department of Chemistry and Chemical Biology, Northeastern University, Boston MA USA; Himmel, Michael E. [Biosciences Center, National Renewable Energy Laboratory, Golden CO USA; Tucker, Melvin P. [X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne IL USA; McCann, Maureen C. [Center for Direct Catalytic Conversion Of Biomass to Biofuels (C3Bio), Purdue University, West Lafayette IN USA; Department of Biological Sciences, Purdue University, West Lafayette IN USA; Murphy, Angus S. [Center for Direct Catalytic Conversion Of Biomass to Biofuels (C3Bio), Purdue University, West Lafayette IN USA; Department of Horticulture, Purdue University, West Lafayette IN USA; Department of Plant Science and Landscape Architecture, University of Maryland, College Park MD USA; Peer, Wendy A. [Center for Direct Catalytic Conversion Of Biomass to Biofuels (C3Bio), Purdue University, West Lafayette IN USA; Department of Horticulture, Purdue University, West Lafayette IN USA; Department of Plant Science and Landscape Architecture, University of Maryland, College Park MD USA; Department of Environmental Science and Technology, University of Maryland, College Park MD USA

    2016-04-07

    Conversion of nongrain biomass into liquid fuel is a sustainable approach to energy demands as global population increases. Previously, we showed that iron can act as a catalyst to enhance the degradation of lignocellulosic biomass for biofuel production. However, direct addition of iron catalysts to biomass pretreatment is diffusion-limited, would increase the cost and complexity of biorefinery unit operations and may have deleterious environmental impacts. Here, we show a new strategy for in planta accumulation of iron throughout the volume of the cell wall where iron acts as a catalyst in the deconstruction of lignocellulosic biomass. We engineered CBM-IBP fusion polypeptides composed of a carbohydrate-binding module family 11 (CBM11) and an iron-binding peptide (IBP) for secretion into Arabidopsis and rice cell walls. CBM-IBP transformed Arabidopsis and rice plants show significant increases in iron accumulation and biomass conversion compared to respective controls. Further, CBM-IBP rice shows a 35% increase in seed iron concentration and a 40% increase in seed yield in greenhouse experiments. CBM-IBP rice potentially could be used to address iron deficiency, the most common and widespread nutritional disorder according to the World Health Organization.

  13. Genetic and physiological characterization of two clusters of quantitative trait Loci associated with seed dormancy and plant height in rice.

    Science.gov (United States)

    Ye, Heng; Beighley, Donn H; Feng, Jiuhuan; Gu, Xing-You

    2013-02-01

    Seed dormancy and plant height have been well-studied in plant genetics, but their relatedness and shared regulatory mechanisms in natural variants remain unclear. The introgression of chromosomal segments from weedy into cultivated rice (Oryza sativa) prompted the detection of two clusters (qSD1-2/qPH1 and qSD7-2/qPH7) of quantitative trait loci both associated with seed dormancy and plant height. Together, these two clusters accounted for >96% of the variances for plant height and ~71% of the variances for germination rate in an isogenic background across two environments. On the initial introgression segments, qSD1-2/qPH1 was dissected genetically from OsVp1 for vivipary and qSD7-2/qPH7 separated from Sdr4 for seed dormancy. The narrowed qSD1-2/qPH1 region encompasses the semidwarf1 (sd1) locus for gibberellin (GA) biosynthesis. The qSD1-2/qPH1 allele from the cultivar reduced germination and stem elongation and the mutant effects were recovered by exogenous GA, suggesting that sd1 is a candidate gene of the cluster. In contrast, the effect-reducing allele at qSD7-2/qPH7 was derived from the weedy line; this allele was GA-insensitive and blocked GA responses of qSD1-2/qPH1, including the transcription of a GA-inducible α-amylase gene in imbibed endosperm, suggesting that qSD7-2/qPH7 may work downstream from qSD1-2/qPH1 in GA signaling. Thus, this research established the seed dormancy-plant height association that is likely mediated by GA biosynthesis and signaling pathways in natural populations. The detected association contributed to weed mimicry for the plant stature in the agro-ecosystem dominated by semidwarf cultivars and revealed the potential benefit of semidwarf genes in resistance to preharvest sprouting.

  14. Reinforcement of natural rubber hybrid composites based on marble sludge/Silica and marble sludge/rice husk derived silica

    Directory of Open Access Journals (Sweden)

    Khalil Ahmed

    2014-03-01

    Full Text Available A research has been carried out to develop natural rubber (NR hybrid composites reinforced with marble sludge (MS/Silica and MS/rice husk derived silica (RHS. The primary aim of this development is to scrutinize the cure characteristics, mechanical and swelling properties of such hybrid composite. The use of both industrial and agricultural waste such as marble sludge and rice husk derived silica has the primary advantage of being eco-friendly, low cost and easily available as compared to other expensive fillers. The results from this study showed that the performance of NR hybrid composites with MS/Silica and MS/RHS as fillers is extremely better in mechanical and swelling properties as compared with the case where MS used as single filler. The study suggests that the use of recently developed silica and marble sludge as industrial and agricultural waste is accomplished to provide a probable cost effective, industrially prospective, and attractive replacement to the in general purpose used fillers like china clay, calcium carbonate, and talc.

  15. Development of Elite BPH-Resistant Wide-Spectrum Restorer Lines for Three and Two Line Hybrid Rice.

    Science.gov (United States)

    Fan, Fengfeng; Li, Nengwu; Chen, Yunping; Liu, Xingdan; Sun, Heng; Wang, Jie; He, Guangcun; Zhu, Yingguo; Li, Shaoqing

    2017-01-01

    Hybrid rice has contributed significantly to the world food security. Breeding of elite high-yield, strong-resistant broad-spectrum restorer line is an important strategy for hybrid rice in commercial breeding programs. Here, we developed three elite brown planthopper (BPH)-resistant wide-spectrum restorer lines by pyramiding big-panicle gene Gn8.1 , BPH-resistant genes Bph6 and Bph9 , fertility restorer genes Rf3, Rf4, Rf5 , and Rf6 through molecular marker assisted selection. Resistance analysis revealed that the newly developed restorer lines showed stronger BPH-resistance than any of the single-gene donor parent Luoyang-6 and Luoyang-9. Moreover, the three new restorer lines had broad spectrum recovery capabilities for Honglian CMS, Wild abortive CMS and two-line GMS sterile lines, and higher grain yields than that of the recurrent parent 9,311 under nature field conditions. Importantly, the hybrid crosses also showed good performance for grain yield and BPH-resistance. Thus, the development of elite BPH-resistant wide-spectrum restorer lines has a promising future for breeding of broad spectrum BPH-resistant high-yield varieties.

  16. Genetic characterization and fine mapping of S25, a hybrid male sterility gene, on rice chromosome 12.

    Science.gov (United States)

    Kubo, Takahiko; Yoshimura, Atsushi; Kurata, Nori

    2018-02-10

    Hybrid male sterility genes are important factors in creating postzygotic reproductive isolation barriers in plants. One such gene, S25, is known to cause severe transmission ratio distortion in inter-subspecific progeny of cultivated rice Oryza sativa ssp. indica and japonica. To further characterize the S25 gene, we fine-mapped and genetically characterized the S25 gene using near-isogenic lines with reciprocal genetic backgrounds. We mapped the S25 locus within the 0.67-1.02 Mb region on rice chromosome 12. Further genetic analyses revealed that S25 substantially reduced male fertility in the japonica background, but not in the indica background. In first-generation hybrid progeny, S25 had a milder effect than it had in the japonica background. These results suggest that the expression of S25 is epistatically regulated by at least one partially dominant gene present in the indica genome. This finding supports our previous studies showing that hybrid male sterility due to pollen killer genes results from epistatic interaction with other genes that are hidden in the genetic background.

  17. Effect of forging on mechanical properties of rice husk ash-silicon carbide reinforced Al1100 hybrid composites

    Science.gov (United States)

    Ghanaraja, S.; Gireesha, B. L.; Ravikumar, K. S.; Likith, P.

    2018-04-01

    During the past few years, material design has changed prominence to pursue light weight, environment friendliness, low cost, quality, higher service temperature, higher elastic modulus, improved wear resistance and performance. Straight monolithic materials have limitations in achieving the above decisive factors. To overcome these limitations and to convince the ever increasing demand of modern day technology, Attention has been shifted towards Metal Matrix Composites (MMC). Stir casting route is most hopeful for synthesizing discontinuous reinforcement aluminium matrix composites because of its relative simplicity and easy adaptability with all shape casting process used in metal casting industry. Hybridization of metal matrix composites is the introduction of more than one type/kind, size and shape of reinforcement during processing of composites. It is carried out to obtain synergistic properties of different reinforcements and matrix used, which may not be rea1ised in monolithic alloy or in conventional monocomposites. The present study involves synthesis of hybrid composites by addition of the desired amount of Silicon Carbide (SiC) and Rice Husk Ash (RHA) particles in to the molten Al 1100-Mg alloy through stir casting technique fallowed by hot forging of the cast composites. The influence of increasing in the wt% (3, 6, 9, 12 and 15 wt%) of SiC particles addition (3 wt% Rice husk ash kept constant) on evolution of microstructure is studied through XRD and SEM and their impact on the mechanical properties like hardness and tensile strength of the resulting forged hybrid composites has been investigated.

  18. Translocation kinetics of 14C-photosynthate in hybrid rice grown at different potassium levels

    International Nuclear Information System (INIS)

    Jiang Dean; Shen Yuwei; Xie Xuemin; Rao Lihua; Lu Qing

    1993-01-01

    The kinetics of translocation of 14 C-assimilate in hybrid rice plant was studied with 14 CO 2 fed to functional leaf at the tillering and filling stages. The result indicated that the relationship between percentage (V) of photosynthate exporting out of the source leaf or that of assimilate into sink, expanding young leaf or filling panicle, respectively,and time(t)after introducing 14 CO 2 into the leaf was extremely coincided with the regression equation : v = V (t + k)/K m + (t + k). At the tillering stage, fully extended top leaf could export 66% ∼ 79% of its photosynthate assimilated at different potassium levels, and both export potential and rate of 14 C-photosynthate in the fed leaf decreased under the low potassium (1 ppm K supplied), but the rate obviously increased in the superfluous potassium (80 ppm K supplied) in spite of slightly low exporting capacity. Main sink, the expanding young leaf on the top of stem could obtain 28% ∼ 59% of 14 C-assimilate at various potassium levels. Both the importation potential and rate were lowered with low potassium application while hastened by super-supplied potassium at the same development stage. At the filling stage, source, flag leaf, was able to export 83% ∼ 97% of its photosynthate and low potassium (5 ppm) application not only delayed the time of 14 C-photosynthate exportation but also diminished the export rate, whereas the rate was accelerated by superfluous potassium. Low potassium resulted in decrease both in the capacity and in the rate of assimilate importing into grain, nevertheless, high potassium caused decrease of percentage assimilate importing into grain and the increase of improving rate. Therefore, it was strategically considered that neither deficient nor superfluous potassium application was beneficial for assimilate transportation

  19. Effects of Interaction between Cadmium (Cd) and Selenium (Se) on Grain Yield and Cd and Se Accumulation in a Hybrid Rice (Oryza sativa) System.

    Science.gov (United States)

    Huang, Baifei; Xin, Junliang; Dai, Hongwen; Zhou, Wenjing

    2017-11-01

    A pot experiment was conducted to investigate the interactive effects of cadmium (Cd) and selenium (Se) on their accumulation in three rice cultivars, which remains unclear. The results showed that Se reduced Cd-induced growth inhibition, and increased and decreased Se and Cd concentrations in brown rice, respectively. Cadmium concentrations in all tissues of the hybrid were similar to those in its male parent yet significantly lower than those in its female parent. Selenium reduced Cd accumulation in rice when Cd concentration exceeded 2.0 mg kg -1 ; however Se accumulation depended on the levels of Cd exposure. Finally, Cd had minimal effect on Se translocation within the three cultivars. We concluded that Cd concentration in brown rice is a heritable trait, making crossbreeding a feasible method for cultivating high-yield, low-Cd rice cultivars. Selenium effectively decreased the toxicity and accumulation of Cd, and Cd affected Se uptake but not translocation.

  20. Soil CO 2 fluxes from direct seeding rice fields under two tillage practices in central China

    Science.gov (United States)

    Li, Cheng-fang; Kou, Zhi-kui; Yang, Jin-hua; Cai, Ming-li; Wang, Jin-ping; Cao, Cou-gui

    2010-07-01

    Agricultural practices affect the production and emission of carbon dioxide (CO 2) from paddy soils. It is crucial to understand the effects of tillage and N fertilization on soil CO 2 flux and its influencing factors for a better comprehension of carbon dynamics in subtropical paddy ecosystems. A 2-yr field study was conducted to assess the effects of tillage (conventional tillage [CT] and no-tillage [NT]) and N fertilization (0 and 210 kg N ha -1) on soil CO 2 fluxes during the 2008 and 2009 rice growing seasons in central China. Treatments were established following a split-plot design of a randomized complete block with tillage practices as the main plot and N fertilizer level as the split-plot treatment. The soil CO 2 fluxes were measured 24 times in 2008 and 17 times in 2009. N fertilization did not affect soil CO 2 emissions while tillage affected soil CO 2 emissions, where NT had similar soil CO 2 emissions to CT in 2008, but in 2009, NT significantly increased soil CO 2 emissions. Cumulative CO 2 emissions were 2079-2245 kg CO 2-C ha -1 from NT treatments, and 2084-2141 kg CO 2-C ha -1 from CT treatments in 2008, and were 1257-1401 kg CO 2-C ha -1 from NT treatments, and 1003-1034 kg CO 2-C ha -1 from CT treatments in 2009, respectively. Cumulative CO 2 emissions were significantly related to aboveground biomass and soil organic C. Before drainage of paddy fields, soil CO 2 fluxes were significantly related to soil temperature with correlation coefficients ( R) of 0.67-0.87 in 2008 and 0.69-0.85 in 2009; moreover, the Q 10 values ranged from 1.28 to 1.55 and from 2.10 to 5.21 in 2009, respectively. Our results suggested that NT rice production system appeared to be ineffective in decreasing carbon emission, which suggested that CO 2 emissions from integrated rice-based system should be taken into account to assess effects of tillage.

  1. Map-Based Cloning of Seed Dormancy1-2 Identified a Gibberellin Synthesis Gene Regulating the Development of Endosperm-Imposed Dormancy in Rice.

    Science.gov (United States)

    Ye, Heng; Feng, Jiuhuan; Zhang, Lihua; Zhang, Jinfeng; Mispan, Muhamad S; Cao, Zhuanqin; Beighley, Donn H; Yang, Jianchang; Gu, Xing-You

    2015-11-01

    Natural variation in seed dormancy is controlled by multiple genes mapped as quantitative trait loci in major crop or model plants. This research aimed to clone and characterize the Seed Dormancy1-2 (qSD1-2) locus associated with endosperm-imposed dormancy and plant height in rice (Oryza sativa). qSD1-2 was delimited to a 20-kb region, which contains OsGA20ox2 and had an additive effect on germination. Naturally occurring or induced loss-of-function mutations of the gibberellin (GA) synthesis gene enhanced seed dormancy and also reduced plant height. Expression of this gene in seeds (including endospermic cells) during early development increased GA accumulation to promote tissue morphogenesis and maturation programs. The mutant allele prevalent in semidwarf cultivars reduced the seed GA content by up to 2-fold at the early stage, which decelerated tissue morphogenesis including endosperm cell differentiation, delayed abscisic acid accumulation by a shift in the temporal distribution pattern, and postponed dehydration, physiological maturity, and germinability development. As the endosperm of developing seeds dominates the moisture equilibrium and desiccation status of the embryo in cereal crops, qSD1-2 is proposed to control primary dormancy by a GA-regulated dehydration mechanism. Allelic distribution of OsGA20ox2, the rice Green Revolution gene, was associated with the indica and japonica subspeciation. However, this research provided no evidence that the primitive indica- and common japonica-specific alleles at the presumably domestication-related locus functionally differentiate in plant height and seed dormancy. Thus, the evolutionary mechanism of this agriculturally important gene remains open for discussion. © 2015 American Society of Plant Biologists. All Rights Reserved.

  2. Map-Based Cloning of Seed Dormancy1-2 Identified a Gibberellin Synthesis Gene Regulating the Development of Endosperm-Imposed Dormancy in Rice1

    Science.gov (United States)

    Ye, Heng; Feng, Jiuhuan; Zhang, Lihua; Zhang, Jinfeng; Mispan, Muhamad S.; Cao, Zhuanqin; Beighley, Donn H.; Yang, Jianchang; Gu, Xing-You

    2015-01-01

    Natural variation in seed dormancy is controlled by multiple genes mapped as quantitative trait loci in major crop or model plants. This research aimed to clone and characterize the Seed Dormancy1-2 (qSD1-2) locus associated with endosperm-imposed dormancy and plant height in rice (Oryza sativa). qSD1-2 was delimited to a 20-kb region, which contains OsGA20ox2 and had an additive effect on germination. Naturally occurring or induced loss-of-function mutations of the gibberellin (GA) synthesis gene enhanced seed dormancy and also reduced plant height. Expression of this gene in seeds (including endospermic cells) during early development increased GA accumulation to promote tissue morphogenesis and maturation programs. The mutant allele prevalent in semidwarf cultivars reduced the seed GA content by up to 2-fold at the early stage, which decelerated tissue morphogenesis including endosperm cell differentiation, delayed abscisic acid accumulation by a shift in the temporal distribution pattern, and postponed dehydration, physiological maturity, and germinability development. As the endosperm of developing seeds dominates the moisture equilibrium and desiccation status of the embryo in cereal crops, qSD1-2 is proposed to control primary dormancy by a GA-regulated dehydration mechanism. Allelic distribution of OsGA20ox2, the rice Green Revolution gene, was associated with the indica and japonica subspeciation. However, this research provided no evidence that the primitive indica- and common japonica-specific alleles at the presumably domestication-related locus functionally differentiate in plant height and seed dormancy. Thus, the evolutionary mechanism of this agriculturally important gene remains open for discussion. PMID:26373662

  3. Supplementation of Farta sheep fed hay with graded levels of concentrate mix consisting of noug seed meal and rice bran.

    Science.gov (United States)

    Asmare, Bimrew; Melaku, Solomon; Peters, Kurt J

    2010-10-01

    The study was carried out at Woreta, Ethiopia, to determine feed intake, digestibility, body weight (BW) change, and profitability of Farta sheep fed pasture hay alone or supplemented with graded levels of concentrate mix (CM) consisting of noug seed meal (NSM) and rice bran in 2:1 ratio. Twenty yearling intact male Farta sheep with BW of 16.9 +/- 1.68 kg (mean +/- SD) were used in randomized complete block design arranged into five blocks of four animals. The dietary treatments consisting of sole natural pasture hay (T1, control), hay +200 g of CM dry matter (DM) (T2, low), hay +300 g of CM DM (T3, medium), and hay +400 g of CM DM (T4, high) were randomly assigned to sheep within each block. Common salt and water were available to animals all the time. The supplements were offered twice daily in equal portions at 0800 and 1600 h. Supplementation with the CM increased (P profitability. Among the supplemented treatments, the high level of supplementation resulted in better (P profitability. Thus, the high level of supplementation is recommended based on biological performance and profitability under conditions of this study.

  4. Fermentation of cacao (Theobroma cacao L.) seeds with a hybrid Kluyveromyces marxianus strain improved product quality attributes.

    Science.gov (United States)

    Leal, Gildemberg Amorim; Gomes, Luiz Humberto; Efraim, Priscilla; de Almeida Tavares, Flavio Cesar; Figueira, Antonio

    2008-08-01

    Fermentation of Theobroma cacao (cacao) seeds is an absolute requirement for the full development of chocolate flavor precursors. An adequate aeration of the fermenting cacao seed mass is a fundamental prerequisite for a satisfactory fermentation. Here, we evaluated whether a controlled inoculation of cacao seed fermentation using a Kluyveromyces marxianus hybrid yeast strain, with an increased pectinolytic activity, would improve an earlier liquid drainage ('sweatings') from the fermentation mass, developing a superior final product quality. Inoculation with K. marxianus increased by one third the volume of drained liquid and affected the microorganism population structure during fermentation, which was detectable up to the end of the process. Introduction of the hybrid yeast affected the profile of total seed protein degradation evaluated by polyacrylamide gel electrophoresis, with improved seed protein degradation, and reduction of titrable acidity. Sensorial evaluation of the chocolate obtained from beans fermented with the K. marxianus inoculation was more accepted by analysts in comparison with the one from cocoa obtained through natural fermentation. The increase in mass aeration during the first 24 h seemed to be fundamental for the improvement of fermentation quality, demonstrating the potential application of this improved hybrid yeast strain with superior exogenous pectinolytic activity.

  5. Métodos para avaliar a qualidade fisiológica de sementes de arroz Methods to evaluate physiological quality of rice seeds

    Directory of Open Access Journals (Sweden)

    N.L. de Menezes

    1995-08-01

    Full Text Available Com o objetivo de avaliar a eficiência de diferentes métodos para a determinação da qualidade fisiológica de sementes de arroz, foram utilizados dois grupos de dez lotes de sementes, das variedades BR-IRGA 409 e BR-IRGA 410. A qualidade dos lotes foi determinada através do teor de água, peso de mil sementes, teste de germinação e dos testes de vigor: primeira contagem de germinação, classificação do vigor de plântulas, envelhecimento acelerado, teste de frio modificado, tamanho e massa seca de plântulas e emergência no campo. Concluiu-se que os testes de frio modificado e classificação do vigor de plântulas são capazes de estratificar diferentes lotes de arroz pelo vigor e se correlacionam positivamente com a emergência no campo. O teste de envelhecimento acelerado, sob as condições de 42'C e 100% de umidade relativa do ar, durante 120 horas, estratifica lotes de arroz , em função do vigor das sementes. Os testes de tamanho e massa seca de plântulas, quando eliminam as plântulas anormais e sementes não germinadas, não são capazes de estratificar lotes de sementes de arroz, em função do vigor.Aiming to evaluate the efficiency of different methods to determine the physiological quality of rice seeds, two groups of 10 lots each of the varieties BR-IRGA 409 and BR-IRGA 410 were used. Seed quality was determined through seed water content, weight of 1,000 seeds, germination and vigor tests: first germination counting, classification of seedling vigor, accelerated aging, modified cold test, seedling growth and weight and field emergence. It was concluded that the modified cold test and classification of seedling vigor are capable of stratifying different rice samples according to their vigor and are positively correlated with field emergence. The accelerated aging, under 42'C and 100% relative humidity of air conditions stratifies the samples in relation to seed vigor. The tests of seedling growth and weight, when

  6. The genotype-environment interaction variance in rice-seed protein determination

    International Nuclear Information System (INIS)

    Ismachin, M.

    1976-01-01

    Many environmental factors influence the protein content of cereal seed. This fact procured difficulties in breeding for protein. Yield is another example on which so many environmental factors are of influence. The length of time required by the plant to reach maturity, is also affected by the environmental factors; even though its effect is not too decisive. In this investigation the genotypic variance and the genotype-environment interaction variance which contribute to the total variance or phenotypic variance was analysed, with purpose to give an idea to the breeder how selection should be made. It was found that genotype-environment interaction variance is larger than the genotypic variance in contribution to total variance of protein-seed determination or yield. In the analysis of the time required to reach maturity it was found that genotypic variance is larger than the genotype-environment interaction variance. It is therefore clear, why selection for time required to reach maturity is much easier than selection for protein or yield. Selected protein in one location may be different from that to other locations. (author)

  7. Effects of shading on starch pasting characteristics of indica hybrid rice (Oryza sativa L..

    Directory of Open Access Journals (Sweden)

    Li Wang

    Full Text Available Rice is an important staple crop throughout the world, but environmental stress like low-light conditions can negatively impact crop yield and quality. Using pot experiments and field experiments, we studied the effects of shading on starch pasting viscosity and starch content with six rice varieties for three years, using the Rapid Visco Analyser to measure starch pasting viscosity. Shading at different growth stages and in different rice varieties all affected the starch pasting characteristics of rice. The effects of shading on starch pasting viscosity at middle and later growth stages were greater than those at earlier stages. Shading enhanced breakdown but reduced hold viscosity and setback at tillering-elongation stage. Most pasting parameters changed significantly with shading after elongation stage. Furthermore, the responses of different varieties to shading differed markedly. The change scope of starch pasting viscosity in Dexiang 4103 was rather small after heading, while that in IIyou 498 and Gangyou 906 was small before heading. We observed clear tendencies in peak viscosity, breakdown, and pasting temperature of the five rice varieties with shading in 2010 and 2011. Correlation analysis indicated that the rice amylose content was negatively correlated with breakdown, but was positively correlated with setback. Based on our results, IIyou 498, Gangyou 906, and Dexiang 4103 had higher shade endurance, making these varieties most suitable for high-quality rice cultivation in low-light regions.

  8. Effects of shading on starch pasting characteristics of indica hybrid rice (Oryza sativa L.).

    Science.gov (United States)

    Wang, Li; Deng, Fei; Ren, Wan-Jun; Yang, Wen-Yu

    2013-01-01

    Rice is an important staple crop throughout the world, but environmental stress like low-light conditions can negatively impact crop yield and quality. Using pot experiments and field experiments, we studied the effects of shading on starch pasting viscosity and starch content with six rice varieties for three years, using the Rapid Visco Analyser to measure starch pasting viscosity. Shading at different growth stages and in different rice varieties all affected the starch pasting characteristics of rice. The effects of shading on starch pasting viscosity at middle and later growth stages were greater than those at earlier stages. Shading enhanced breakdown but reduced hold viscosity and setback at tillering-elongation stage. Most pasting parameters changed significantly with shading after elongation stage. Furthermore, the responses of different varieties to shading differed markedly. The change scope of starch pasting viscosity in Dexiang 4103 was rather small after heading, while that in IIyou 498 and Gangyou 906 was small before heading. We observed clear tendencies in peak viscosity, breakdown, and pasting temperature of the five rice varieties with shading in 2010 and 2011. Correlation analysis indicated that the rice amylose content was negatively correlated with breakdown, but was positively correlated with setback. Based on our results, IIyou 498, Gangyou 906, and Dexiang 4103 had higher shade endurance, making these varieties most suitable for high-quality rice cultivation in low-light regions.

  9. Interspecific hybridization and inbreeding effect in seed from a Eucalyptus grandis x E. urophylla clonal orchard in Brazil

    Directory of Open Access Journals (Sweden)

    Campinhos Eduardo N.

    1998-01-01

    Full Text Available We used allozyme markers to estimate the amount of natural hybridization between Eucalyptus grandis and E. urophylla in a 7.4-hectare commercial hybrid-seed orchard planted in Espírito Santo, Brazil. This orchard was planted in 1982 using a honeycomb design, with each hexagonal plot containing one E. grandis tree surrounded by six E. urophylla trees. There were 267 replicated hexagonal plots in the orchard. Seeds were harvested from the E. grandis clone only. The multilocus outcrossing rate estimated for the E. grandis clone averaged 70.2%, ranging from 33.0 to 99.0% among individual trees. Contaminant pollination, inferred from progeny genotypes containing alleles not present in the seven parental clones, accounted for 14.4% of the hybrid seed. Contaminant pollen was attributed to neighboring eucalyptus stands isolated from the orchard by a 400-m wide belt of native forest. Inbred and hybrid progenies were identified by their allozyme genotypes and transplanted to the field. Field growth of inbred progeny was 30% lower than that of hybrid plants at two and three years of age.

  10. Tissue culture-induced genetic and epigenetic alterations in rice pure-lines, F1 hybrids and polyploids.

    Science.gov (United States)

    Wang, Xiaoran; Wu, Rui; Lin, Xiuyun; Bai, Yan; Song, Congdi; Yu, Xiaoming; Xu, Chunming; Zhao, Na; Dong, Yuzhu; Liu, Bao

    2013-05-05

    Genetic and epigenetic alterations can be invoked by plant tissue culture, which may result in heritable changes in phenotypes, a phenomenon collectively termed somaclonal variation. Although extensive studies have been conducted on the molecular nature and spectrum of tissue culture-induced genomic alterations, the issue of whether and to what extent distinct plant genotypes, e.g., pure-lines, hybrids and polyploids, may respond differentially to the tissue culture condition remains poorly understood. We investigated tissue culture-induced genetic and epigenetic alterations in a set of rice genotypes including two pure-lines (different subspecies), a pair of reciprocal F1 hybrids parented by the two pure-lines, and a pair of reciprocal tetraploids resulted from the hybrids. Using two molecular markers, amplified fragment length polymorphism (AFLP) and methylation-sensitive amplified polymorphism (MSAP), both genetic and DNA methylation alterations were detected in calli and regenerants from all six genotypes, but genetic alteration is more prominent than epigenetic alteration. While significant genotypic difference was observed in frequencies of both types of alterations, only genetic alteration showed distinctive features among the three types of genomes, with one hybrid (N/9) being exceptionally labile. Surprisingly, difference in genetic alteration frequencies between the pair of reciprocal F1 hybrids is much greater than that between the two pure-line subspecies. Difference also exists in the pair of reciprocal tetraploids, but is to a less extent than that between the hybrids. The steady-state transcript abundance of genes involved in DNA repair and DNA methylation was significantly altered in both calli and regenerants, and some of which were correlated with the genetic and/or epigenetic alterations. Our results, based on molecular marker analysis of ca. 1,000 genomic loci, document that genetic alteration is the major cause of somaclonal variation in rice

  11. Nucleic acids in mummified plant seeds: screening of twelve specimens by gel-electrophoresis, molecular hybridization and DNA cloning.

    Science.gov (United States)

    Rollo, F; La Marca, A; Amici, A

    1987-02-01

    Twelve seed specimens of varying ages and from different archaeological sites were analyzed for the presence of polymerized DNA and RNA. Amongst the samples tested, one of Vitis vinifera from an archaeological site in Iran (2,000-3,000 B.C.) was found to be completely devoid of nucleic acids. Zea mais seeds of Precolumbial age from Peru (about 800 A.D.) contained depolymerized DNA and RNA. Samples of Vitis vinifera and Rubus sp. from a Lombard archaeological site (800 A.D.) as well as radiocarbon dated seeds from the site of the "Spring Sanctuary" near Metaponto (I-IV century B.C.) were found to contain polymerized DNA and rRNA bands. However the electrophoretic properties of the rRNAs in one case and hybridization experiments performed with cloned seed DNA in the other, clearly demonstrated that the polymerized nucleic acids were not of plant origin.

  12. Massive primordial black holes from hybrid inflation as dark matter and the seeds of galaxies

    Science.gov (United States)

    Clesse, Sébastien; García-Bellido, Juan

    2015-07-01

    In this paper we present a new scenario where massive primordial black holes (PBHs) are produced from the collapse of large curvature perturbations generated during a mild-waterfall phase of hybrid inflation. We determine the values of the inflaton potential parameters leading to a PBH mass spectrum peaking on planetarylike masses at matter-radiation equality and producing abundances comparable to those of dark matter today, while the matter power spectrum on scales probed by cosmic microwave background (CMB) anisotropies agrees with Planck data. These PBHs could have acquired large stellar masses today, via merging, and the model passes both the constraints from CMB distortions and microlensing. This scenario is supported by Chandra observations of numerous BH candidates in the central region of Andromeda. Moreover, the tail of the PBH mass distribution could be responsible for the seeds of supermassive black holes at the center of galaxies, as well as for ultraluminous x-ray sources. We find that our effective hybrid potential can originate e.g. from D-term inflation with a Fayet-Iliopoulos term of the order of the Planck scale but sub-Planckian values of the inflaton field. Finally, we discuss the implications of quantum diffusion at the instability point of the potential, able to generate a Swiss-cheese-like structure of the Universe, eventually leading to apparent accelerated cosmic expansion.

  13. Temperature influence during seed filling on tocopherol concentration in a traditional sunflower hybrid

    Directory of Open Access Journals (Sweden)

    Nolasco, S.M.

    2007-06-01

    Full Text Available The effect of night temperature during short periods in seed filling on oil tocopherol content and tocopherol/linoleic acid ratio was investigated in a traditional sunflower hybrid. Seeds were sown in the field at Balcarce on the 3rd and 22nd of November. In each experiment, treatments in which night temperature was increased at three consecutive periods of 200 °C day (base temperature: 6 °C were applied.Tocopherol concentration was reduced when night temperature was increased early in seed filling. Such an increase could be attributed to a correlative increase in the daily average temperature, as no differences in tocopherol concentration were found when plants were cultivated in growth chambers under different day/night temperature but at the same daily average temperature. Temperature affected tocopherol concentration mainly by affecting the oil weight per seed.The tocopherol/linoleic acid ratio was not affected by temperature.Se investigó el efecto de la temperatura durante períodos cortos en el llenado de las semillas sobre la concentración de tocoferoles y la relación tocoferoles/ácido linoleico en un híbrido tradicional de girasol. Se realizó una siembra en campo en Balcarce el 3 y el 22 de noviembre. En cada experimento, se aplicaron tratamientos donde se incrementó la temperatura de la noche en tres períodos consecutivos de 200 °C día (temperatura base: 6 °C. La concentración de tocoferoles disminuyó cuando se incrementó la temperatura de la noche temprano durante el llenado de las semillas. Dicho aumento puede ser atribuido a aumentos en la temperatura media diaria ya que no se observaron diferencias en la concentración de tocoferoles cuando se cultivaron plantas en cámaras de crecimiento con distinta temperatura nocturna y la misma temperatura media diaria. La temperatura afectó la concentración de tocoferoles principalmente al afectar el peso de aceite por semilla. La relación tocoferoles/

  14. Implementation of bio-fungicides and seed treatment in organic rice cv. KDML 105 farming.

    Science.gov (United States)

    Thobunluepop, Pitipong

    2009-08-15

    This study was aimed to evaluate the several chemical compounds of relatively composite structure with antifungal activity from Thai local medical plants. The antifungal activity of Stemona curtisii HK. f., Stemona tuberose L., Acorus calamus L., Eugenia caryophyllus, Memmea siamensis Kost. and an eugenol active compound were studied in vitro. Four pathogenic seed borne fungi, Alternaria solani, Colletotrichum sp., Fusarium moniliforme and Rhizoctonia solani were used as target organisms. The agar overlay technique and spore inhibition techniques were applied for the determination of their essential oil and active compound antifungal activity at various concentration; 0.10, 0.25, 0.50 and 1.00% (v/v) and untreated as control (0% v/v). Eugenol active compound showed the strongest antifungal activity on all species of tested fungal species. On the other hand, the antifungal activity of those bio-fungicides was lined up into a series from strong to low, as follows: Eugenia caryophyllus > Acorus calamus Linn. > Stemona tuberosa L. > Stemona curtisii Hk.f, while Mammea siamensis Kost. could not control any fungal species. Moreover, after eugenol application, lysis of spore and inhibition of mycelium growth were detected. Microscopic analysis exhibited complete lysis of spores after 24 h at a concentration of 1.00% v/v. Moreover, at the same concentration and 96 h incubation the mycelia growth was completely inhibited.

  15. OsRACK1 Is Involved in Abscisic Acid- and H2O2-Mediated Signaling to Regulate Seed Germination in Rice (Oryza sativa, L.)

    Science.gov (United States)

    Zhang, Dongping; Chen, Li; Li, Dahong; Lv, Bing; Chen, Yun; Chen, Jingui; XuejiaoYan; Liang, Jiansheng

    2014-01-01

    The receptor for activated C kinase 1 (RACK1) is one member of the most important WD repeat–containing family of proteins found in all eukaryotes and is involved in multiple signaling pathways. However, compared with the progress in the area of mammalian RACK1, our understanding of the functions and molecular mechanisms of RACK1 in the regulation of plant growth and development is still in its infancy. In the present study, we investigated the roles of rice RACK1A gene (OsRACK1A) in controlling seed germination and its molecular mechanisms by generating a series of transgenic rice lines, of which OsRACK1A was either over-expressed or under-expressed. Our results showed that OsRACK1A positively regulated seed germination and negatively regulated the responses of seed germination to both exogenous ABA and H2O2. Inhibition of ABA biosynthesis had no enhancing effect on germination, whereas inhibition of ABA catabolism significantly suppressed germination. ABA inhibition on seed germination was almost fully recovered by exogenous H2O2 treatment. Quantitative analyses showed that endogenous ABA levels were significantly higher and H2O2 levels significantly lower in OsRACK1A-down regulated transgenic lines as compared with those in wildtype or OsRACK1A-up regulated lines. Quantitative real-time PCR analyses showed that the transcript levels of OsRbohs and amylase genes, RAmy1A and RAmy3D, were significantly lower in OsRACK1A-down regulated transgenic lines. It is concluded that OsRACK1A positively regulates seed germination by controlling endogenous levels of ABA and H2O2 and their interaction. PMID:24865690

  16. Farm family effects of adopting improved and hybrid sorghum seed in the Sudan Savanna of West Africa.

    Science.gov (United States)

    Smale, Melinda; Assima, Amidou; Kergna, Alpha; Thériault, Véronique; Weltzien, Eva

    2018-01-01

    Uptake of improved sorghum varieties in the Sudan Savanna of West Africa has been limited, despite the economic importance of the crop and long-term investments in sorghum improvement. One reason why is that attaining substantial yield advantages has been difficult in this harsh, heterogeneous growing environment. Release in Mali of the first sorghum hybrids in Sub-Saharan Africa that have been developed primarily from local germplasm has the potential to change this situation. Utilizing plot data collected in Mali, we explain the adoption of improved seed with an ordered logit model and apply a multivalued treatment effects model to measure impacts on farm families, differentiating between improved varieties and hybrids. Since farm families both consume and sell their sorghum, we consider effects on consumption patterns as well as productivity. Status within the household, conferred by gender combined with marital status, generation, and education, is strongly related to the improvement status of sorghum seed planted in these extended family households. Effects of hybrid use on yields are large, widening the range of food items consumed, reducing the share of sorghum in food purchases, and contributing to a greater share of the sorghum harvest sold. Use of improved seed appears to be associated with a shift toward consumption of other cereals, and also to greater sales shares. Findings support on-farm research concerning yield advantages, also suggesting that the use of well-adapted sorghum hybrids could contribute to diet diversification and the crop's commercialization by smallholders.

  17. Cadmium accumulation characteristics of low-cadmium rice (Oryza sativa L.) line and F1 hybrids grown in cadmium-contaminated soils.

    Science.gov (United States)

    Li, Kun; Yu, Haiying; Li, Tingxuan; Chen, Guangdeng; Huang, Fu

    2017-07-01

    Cadmium (Cd) pollution has threatened severely to food safety and human health. A pot experiment and a field experiment were conducted to investigate the difference of Cd accumulation between rice (Oryza sativa L.) lines and F 1 hybrids in Cd-contaminated soils. The adverse effect on biomass of rice lines was greater than that of F 1 hybrids under Cd treatments in the pot experiment. The variations of Cd concentration among rice cultivars in different organs were smaller in stem and leaf, but larger in root and ear. Average proportion of Cd in root of F 1 hybrids was 1.39, 1.39, and 1.16 times higher than those of rice lines at the treatment of 1, 2, and 4 mg Cd kg -1 soil, respectively. Cd concentrations in ear of F 1 hybrids were significantly lower than rice lines with the reduction from 29.24 to 50.59%. Cd concentrations in brown rice of all F 1 hybrids were less than 0.2 mg kg -1 at 1 mg Cd kg -1 soil, in which Lu98A/YaHui2816, 5406A/YaHui2816, and C268A/YaHui2816 could be screened out as cadmium-safe cultivars (CSCs) for being safe even at 2 mg Cd kg -1 soil. C268A/YaHui2816 showed the lowest Cd concentration in root among F 1 hybrids, while Lu98A/YaHui2816 and 5406A/YaHui2816 showed lower capability of Cd translocation from root to shoot under Cd exposure, which eventually caused the lower Cd accumulation in brown rice. The lower level of Cd translocation contributed to reducing the accumulation of Cd in brown rice had been validated by the field experiment. Thus, Lu98A/YaHui2816, 5406A/YaHui2816, and C268A/YaHui2816 could be considered as potential CSCs to cultivate in Cd-contaminated soils (<2 mg Cd kg -1 soil).

  18. seeds

    African Journals Online (AJOL)

    Owner

    peptidohydrolase (8.0%) from mung bean seedlings. (Baumgartner and Chrispeels, 1977), EP-HG (4.5%) from horse gram seedlings ( Rajeswari, 1997), acidic protease (15%) from germinating winged-bean seeds. (Usha and Singh, 1996) and EP-1 (1.6%) from barley seedlings and GA3-induced cysteine protease (3.38%).

  19. Gene, protein and network of male sterility in rice

    Directory of Open Access Journals (Sweden)

    Wang eKun

    2013-04-01

    Full Text Available Rice is one of the most important model crop plants whose heterosis has been well exploited in commercial hybrid seed production via a variety of types of male sterile lines. Hybrid rice cultivation area is steadily expanding around the world, especially in Southern Asia. Characterization of genes and proteins related to male sterility aims to understand how and why the male sterility occurs, and which proteins are the key players for microspores abortion. Recently, a series of genes and proteins related to cytoplasmic male sterility, photoperiod sensitive male sterility, self-incompatibility and other types of microspores deterioration have been characterized through genetics or proteomics. Especially the latter, offers us a powerful and high throughput approach to discern the novel proteins involving in male-sterile pathways which may help us to breed artificial male-sterile system. This represents an alternative tool to meet the critical challenge of further development of hybrid rice. In this paper, we reviewed the recent developments in our understanding of male sterility in rice hybrid production across gene, protein and integrated network levels, and also, present a perspective on the engineering of male sterile lines for hybrid rice production.

  20. Teor de proteína e qualidade fisiológica de sementes de arroz Protein content and physiological quality of rice seeds

    Directory of Open Access Journals (Sweden)

    Rafael Pivotto Bortolotto

    2008-01-01

    Full Text Available O trabalho teve como objetivo avaliar o teor de proteína como elemento auxiliar na determinação da qualidade fisiológica de sementes de arroz, além de correlacioná-la com a emergência em campo. Foram utilizados seis lotes de sementes de arroz, sendo três lotes da cultivar IRGA 417 e três lotes da cultivar IRGA 422 CL, submetidas ao conjunto de testes, para caracterizar o potencial fisiológico dos lotes: germinação, primeira contagem de germinação, envelhecimento acelerado, frio sem terra, comprimento de plântula e massa seca de plântula. Após a determinação da qualidade inicial dos lotes foi aplicado novo conjunto de testes, composto pelo teor de proteína bruta e pelas avaliações das plântulas e plantas em campo. Conclui-se que o teor de proteína bruta é capaz de identificar diferenças entre lotes de arroz, em função da qualidade das sementes, e correlacionar-se com a emergência em campo, quando ocorre em condições desfavoráveis; portanto, trata-se de uma determinação promissora para associação aos testes convencionais a fim de avaliar o potencial fisiológico das sementes de arroz.This work aimed to evaluate the protein content as an aiding tool in the determination of the physiological quality of rice seeds, as well as to correlate the results with field emergence. Six lots of rice seeds were used, i. e., three lots were of cultivar IRGA 417 and three of IRGA 422 CL, which were submitted to a set of tests in order to measure the following physiological qualities of the lots: germination, first count germination, accelerated aging, cold test (without soil, length and dry mass of seedlings. After determining the initial quality of the lots, a new set of tests such as crude protein content and seedlings and plants evaluations in the field were carried out. It was concluded that crude protein content is capable to identify differences between rice lots with different seed quality and to correlate with field

  1. significance of rice sheath photosynthesis: yield determination by c ...

    African Journals Online (AJOL)

    ACSS

    1State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha 410125, P.R. China. 2School of ... for contribution rates of sheath photosynthesis to economical yield. ..... related processes during ripening in rice plants.

  2. Duplication and Loss of Function of Genes Encoding RNA Polymerase III Subunit C4 Causes Hybrid Incompatibility in Rice

    Directory of Open Access Journals (Sweden)

    Giao Ngoc Nguyen

    2017-08-01

    Full Text Available Reproductive barriers are commonly observed in both animals and plants, in which they maintain species integrity and contribute to speciation. This report shows that a combination of loss-of-function alleles at two duplicated loci, DUPLICATED GAMETOPHYTIC STERILITY 1 (DGS1 on chromosome 4 and DGS2 on chromosome 7, causes pollen sterility in hybrid progeny derived from an interspecific cross between cultivated rice, Oryza sativa, and an Asian annual wild rice, O. nivara. Male gametes carrying the DGS1 allele from O. nivara (DGS1-nivaras and the DGS2 allele from O. sativa (DGS2-T65s were sterile, but female gametes carrying the same genotype were fertile. We isolated the causal gene, which encodes a protein homologous to DNA-dependent RNA polymerase (RNAP III subunit C4 (RPC4. RPC4 facilitates the transcription of 5S rRNAs and tRNAs. The loss-of-function alleles at DGS1-nivaras and DGS2-T65s were caused by weak or nonexpression of RPC4 and an absence of RPC4, respectively. Phylogenetic analysis demonstrated that gene duplication of RPC4 at DGS1 and DGS2 was a recent event that occurred after divergence of the ancestral population of Oryza from other Poaceae or during diversification of AA-genome species.

  3. Fabrication of Activated Rice Husk Charcoal by Slip Casting as a Hybrid Material for Water Filter Aid

    International Nuclear Information System (INIS)

    Tuaprakone, T; Wongphaet, N; Wasanapiarnpong, T

    2011-01-01

    Activated charcoal has been widely used as an odor absorbent in household and water purification industry. Filtration equipment for drinking water generally consists of four parts, which are microporous membrane (porous alumina ceramic or diatomite, or porous polymer), odor absorbent (activated carbon), hard water treatment (ion exchange resin), and UV irradiation. Ceramic filter aid is usually prepared by slip casting of alumina or diatomite. The membrane offers high flux, high porosity and maximum pore size does not exceed 0.3 μm. This study investigated the fabrication of hybrid activated charcoal tube for water filtration and odor absorption by slip casting. The suitable rice husk charcoal and water ratio was 48 to 52 wt% by weight with 1.5wt% (by dry basis) of CMC binder. The green rice husk charcoal bodies were dried and fired between 700-900 deg. C in reduction atmosphere. The resulting prepared slip in high speed porcelain pot for 60 min and sintered at 700 deg. C for 1 h showed the highest specific surface area as 174.95 m 2 /g. The characterizations of microstructure and pore size distribution as a function of particle size were investigated.

  4. Fabrication of Activated Rice Husk Charcoal by Slip Casting as a Hybrid Material for Water Filter Aid

    Science.gov (United States)

    Tuaprakone, T.; Wongphaet, N.; Wasanapiarnpong, T.

    2011-04-01

    Activated charcoal has been widely used as an odor absorbent in household and water purification industry. Filtration equipment for drinking water generally consists of four parts, which are microporous membrane (porous alumina ceramic or diatomite, or porous polymer), odor absorbent (activated carbon), hard water treatment (ion exchange resin), and UV irradiation. Ceramic filter aid is usually prepared by slip casting of alumina or diatomite. The membrane offers high flux, high porosity and maximum pore size does not exceed 0.3 μm. This study investigated the fabrication of hybrid activated charcoal tube for water filtration and odor absorption by slip casting. The suitable rice husk charcoal and water ratio was 48 to 52 wt% by weight with 1.5wt% (by dry basis) of CMC binder. The green rice husk charcoal bodies were dried and fired between 700-900 °C in reduction atmosphere. The resulting prepared slip in high speed porcelain pot for 60 min and sintered at 700 °C for 1 h showed the highest specific surface area as 174.95 m2/g. The characterizations of microstructure and pore size distribution as a function of particle size were investigated.

  5. Fabrication of Activated Rice Husk Charcoal by Slip Casting as a Hybrid Material for Water Filter Aid

    Energy Technology Data Exchange (ETDEWEB)

    Tuaprakone, T; Wongphaet, N; Wasanapiarnpong, T, E-mail: tonggogo@hotmail.com [Research Unit of Advanced Ceramic, Department of Materials Science, Faculty of Science, Chulalongkorn University, Bangkok (Thailand)

    2011-04-15

    Activated charcoal has been widely used as an odor absorbent in household and water purification industry. Filtration equipment for drinking water generally consists of four parts, which are microporous membrane (porous alumina ceramic or diatomite, or porous polymer), odor absorbent (activated carbon), hard water treatment (ion exchange resin), and UV irradiation. Ceramic filter aid is usually prepared by slip casting of alumina or diatomite. The membrane offers high flux, high porosity and maximum pore size does not exceed 0.3 {mu}m. This study investigated the fabrication of hybrid activated charcoal tube for water filtration and odor absorption by slip casting. The suitable rice husk charcoal and water ratio was 48 to 52 wt% by weight with 1.5wt% (by dry basis) of CMC binder. The green rice husk charcoal bodies were dried and fired between 700-900 deg. C in reduction atmosphere. The resulting prepared slip in high speed porcelain pot for 60 min and sintered at 700 deg. C for 1 h showed the highest specific surface area as 174.95 m{sup 2}/g. The characterizations of microstructure and pore size distribution as a function of particle size were investigated.

  6. Combined Effects of Nutrient and Pesticide Management on Soil Microbial Activity in Hybrid Rice Double Annual Cropping System

    Institute of Scientific and Technical Information of China (English)

    XIEXiao-mei; LIAOMin; LIUWei-ping; SusanneKLOSE

    2004-01-01

    Combined effects on soil microbial activity of nutrient and pesticide management in hybrid rice double annual cropping system were studied. Results of field experiment demonstrated significant changes in soil microbial biomass phospholipid contents,abundance of heterotrophic bacteria and proteolytic bacteria, electron transport system (ETS)/dehydrogenase activity, soil protein contents under different management practices and at various growth stages. Marked depletions in the soil microbial biomass phospholipid contents were found with the advancement of crop growth stages, while the incorporation of fertilizers and/or pesticides also induced slight changes, and the lowest microbial biomass phospholipid content was found with pesticides application alone. A decline in the bacterial abundance of heterotrophic bacteria and proteolytic bacteria was observed during the continuance of crop growth, while the lowest abundance of heterotrophic bacteria and proteolyrJc bacteria was found with pesticides application alone, which coincided with the decline of soil microbial biomass. A consistent increase in the electron transport svstem activit), was measured during the different crop growth stages of rice. The use of fertilizers (NPK) alone or combined with pesticides increased it, while a decline was noticed with pesticides application alone as compared with the control.The soil protein content was found to be relatively stable with fertilizers and/or pesticides application at various growth stages in both crops undertaken, but notable changes were detected at different growrh stages

  7. Combined Effects of Nutrient and Pesticide Management on Soil Microbial Activity in Hybrid Rice Double Annual Cropping System

    Institute of Scientific and Technical Information of China (English)

    XIE Xiao-mei; LIAO Min; LIU Wei-ping; Susanne KLOSE

    2004-01-01

    Combined effects on soil microbial activity of nutrient and pesticide management in hybrid rice double annual cropping system were studied. Results of field experiment demonstrated significant changes in soil microbial biomass phospholipid contents,abundance of heterotrophic bacteria and proteolytic bacteria, electron transport system (ETS)/dehydrogenase activity, soil protein contents under different management practices and at various growth stages. Marked depletions in the soil microbial biomass phospholipid contents were found with the advancement of crop growth stages, while the incorporation of fertilizers and/or pesticides also induced slight changes, and the lowest microbial biomass phospholipid content was found with pesticides application alone. A decline in the bacterial abundance of heterotrophic bacteria and proteolytic bacteria was observed during the continuance of crop growth, while the lowest abundance of heterotrophic bacteria and proteolytic bacteria was found with pesticides application alone, which coincided with the decline of soil microbial biomass. A consistent increase in the electron transport system activity was measured during the different crop growth stages of rice. The use of fertilizers (NPK) alone or combined with pesticides increased it, while a decline was noticed with pesticides application alone as compared with the control.The soil protein content was found to be relatively stable with fertilizers and/or pesticides application at various growth stages in both crops undertaken, but notable changes were detected at different growth stages.

  8. Possible mechanisms of pollination failure in hybrid carrot seed and implications for industry in a changing climate.

    Science.gov (United States)

    Broussard, Melissa Ann; Mas, Flore; Howlett, Brad; Pattemore, David; Tylianakis, Jason M

    2017-01-01

    Approximately one-third of our food globally comes from insect-pollinated crops. The dependence on pollinators has been linked to yield instability, which could potentially become worse in a changing climate. Insect-pollinated crops produced via hybrid breeding (20% of fruit and vegetable production globally) are especially at risk as they are even more reliant on pollinators than open-pollinated plants. We already observe a wide range of fruit and seed yields between different cultivars of the same crop species, and it is unknown how existing variation will be affected in a changing climate. In this study, we examined how three hybrid carrot varieties with differential performance in the field responded to three temperature regimes (cooler than the historical average, average, and warmer that the historical average). We tested how temperature affected the plants' ability to set seed (seed set, pollen viability) as well as attract pollinators (nectar composition, floral volatiles). We found that there were significant intrinsic differences in nectar phenolics, pollen viability, and seed set between the carrot varieties, and that higher temperatures did not exaggerate those differences. However, elevated temperature did negatively affect several characteristics relating to the attraction and reward of pollinators (lower volatile production and higher nectar sugar concentration) across all varieties, which may decrease the attractiveness of this already pollinator-limited crop. Given existing predictions of lower pollinator populations in a warmer climate, reduced attractiveness would add yet another challenge to future food production.

  9. [Mechanisms of subspecies differentiation in a filial generation of rice indica-japonica hybridization under different ecological conditions].

    Science.gov (United States)

    Wang, He-Tong; Jin, Feng; Jiang, Yi-Jun; Lin, Qing-Shan; Xu, Hai; Chen, Wen-Fu; Xu, Zheng-Jin

    2013-11-01

    Indica-japonica hybridization is one of the most important breeding methods in China, whereas identifying subspecies differentiation mechanisms is the key in indica-japonica hybridization breeding. By using InDels (Insert/Deletion) and ILPs (Intron Length Polymorphism), an analysis was made on the F6 populations derived from the hybridization of indica-japonica (Qishanzhan/Akihikari) planted in Liaoning and Guangdong provinces and generated by bulk harvesting (BM), single-seed descent methods (SSD), and pedigree method (PM). No segregation distortion was observed for the BM and SSD populations. The frequency distribution of japonica kinship percentage (Dj) was concentrated in 40%-60%. The PM populations in the two provinces presented indica-deviated distribution (30%-55%), with significant difference between Guangdong (38%) and Liaoning (42%). In addition, there was a significant positive correlation between the Dj and the kinship of functional gene regions in the BM and SSD populations. However, part of the positive correlation was broken in the PM populations that showed a regular distribution in the genotype patterns of indica and japonica loci. The above results demonstrated that artificial selection could be the main factor affecting the population differentiation in indica-japonica hybridization, and, with the synergistic effect of natural selection, induced the phenomenon of segregation distortion. There existed a close relationship between the differentiation of subspecies and the important agronomic traits, which could be the main reason why indica-japonica hybridiation breeding could not achieve the expected effect of combining the two subspecies advantages.

  10. Physiological and Biochemical Characteristics in Flag Leaves of the C Liangyou Series of Hybrid Rice Combinations at Late Growth Stages

    Directory of Open Access Journals (Sweden)

    Wen-bang TANG

    2010-12-01

    Full Text Available The contents of chlorophyll, soluble sugars, soluble proteins and thiobarbituric acid reaction substance (TBARS, chlorophyll fluorescence parameters, net photosynthetic rate as well as the activities of superoxide dismutase (SOD and peroxidase (POD of flag leaves at the late growth stages were studied by using C Liangyou series of hybrid rice combinitions as material and Shanyou 63 as control. The C Liangyou series of hybrid rice combinations used in the experiment included C Liangyou 396, C Liangyou 87, C Liangyou 755 and C Liangyou 34, which all used C815S as male sterile line. The contents of chlorophyll, soluble sugars and soluble proteins in flag leaves of the C Liangyou series combinations at the late growth stages were higher than those of the control, whereas the TBARS content was lower than that of the control. The activities of SOD and POD were significantly higher than those of the control on the 7th day after heading, and then decreased slowly. FPSII value and qP value of flag leaves decreased at the late growth stages, and these two parameters in flag leaves of the C Liangyou series combinations were higher than those of the control, while the qN value increased at the late growth stages and was lower than that of the control. The net photosynthetic rate of flag leaves at the late growth stage was higher compared with the control. These results suggest that slow senescence and strong photosynthetic capability in flag leaves at the late growth stages are the physiological basis of the C Liangyou series combinations.

  11. QTL mapping of combining ability and heterosis of agronomic traits in rice backcross recombinant inbred lines and hybrid crosses.

    Directory of Open Access Journals (Sweden)

    Zhen Qu

    Full Text Available BACKGROUND: Combining ability effects are very effective genetic parameters in deciding the next phase of breeding programs. Although some breeding strategies on the basis of evaluating combining ability have been utilized extensively in hybrid breeding, little is known about the genetic basis of combining ability. Combining ability is a complex trait that is controlled by polygenes. With the advent and development of molecular markers, it is feasible to evaluate the genetic bases of combining ability and heterosis of elite rice hybrids through QTL analysis. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we first developed a QTL-mapping method for dissecting combining ability and heterosis of agronomic traits. With three testcross populations and a BCRIL population in rice, biometric and QTL analyses were conducted for ten agronomic traits. The significance of general combining ability and special combining ability for most of the traits indicated the importance of both additive and non-additive effects on expression levels. A large number of additive effect QTLs associated with performance per se of BCRIL and general combining ability, and dominant effect QTLs associated with special combining ability and heterosis were identified for the ten traits. CONCLUSIONS/SIGNIFICANCE: The combining ability of agronomic traits could be analyzed by the QTL mapping method. The characteristics revealed by the QTLs for combining ability of agronomic traits were similar with those by multitudinous QTLs for agronomic traits with performance per se of BCRIL. Several QTLs (1-6 in this study were identified for each trait for combining ability. It demonstrated that some of the QTLs were pleiotropic or linked tightly with each other. The identification of QTLs responsible for combining ability and heterosis in the present study provides valuable information for dissecting genetic basis of combining ability.

  12. A novel epistatic interaction at two loci causing hybrid male sterility in an inter-subspecific cross of rice (Oryza sativa L.).

    Science.gov (United States)

    Kubo, Takahiko; Yamagata, Yoshiyuki; Eguchi, Maki; Yoshimura, Atsushi

    2008-12-01

    Postzygotic reproductive isolation (RI) often arises in inter-subspecific crosses as well as inter-specific crosses of rice (Oryza sativa L.). To further understand the genetic architecture of the postzygotic RI, we analyzed genes causing hybrid sterility and hybrid breakdown in a rice inter-subspecific cross. Here we report hybrid male sterility caused by epistatic interaction between two novel genes, S24 and S35, which were identified on rice chromosomes 5 and 1, respectively. Genetic analysis using near-isogenic lines (NILs) carrying IR24 (ssp. indica) segments with Asominori (ssp. japonica) genetic background revealed a complicated aspect of the epistasis. Allelic interaction at the S24 locus in the heterozygous plants caused abortion of male gametes carrying the Asominori allele (S24-as) independent of the S35 genotype. On the other hand, male gametes carrying the Asominori allele at the S35 locus (S35-as) showed abortion only when the IR24 allele at the S24 locus (S24-ir) was concurrently introgressed into the S35 heterozygous plants, indicating that the sterility phenotype due to S35 was dependent on the S24 genotype through negative epistasis between S24-ir and S35-as alleles. Due to the interaction between S24 and S35, self-pollination of the double heterozygous plants produced pollen-sterile progeny carrying the S24-ir/S24-ir S35-as/S35-ir genotype in addition to the S24 heterozygous plants. This result suggests that the S35 gene might function as a modifier of S24. This study presents strong evidence for the importance of epistatic interaction as a part of the genetic architecture of hybrid sterility in rice. In addition, it suggests that diverse systems have been developed as postzygotic RI mechanisms within the rice.

  13. Floristic diversity of the soil weed seed bank in a rice-growing area of Brazil: in situ and ex situ evaluation

    Directory of Open Access Journals (Sweden)

    Mário Luiz Ribeiro Mesquita

    2013-09-01

    Full Text Available The objective of this study was to compare the ex situ and in situ floristic diversity of the soil weed seed bank of a rice field in northeastern Brazil. In a rice field in the county of Bacabal, located in the state of Maranhão, thirty 25-m² plots were laid out. From 15 plots, soil samples (6/plot; n = 90 were taken with a soil probe (25 × 16 × 3 cm and placed in aluminum trays in the greenhouse. From the remaining 15 plots, weed samples (6/plot; n = 90 were taken with the same soil probe. The number of seeds was estimated by germination. We evaluated the numbers of species and individuals, as well as the density, frequency, abundance and importance value (IV for each species. Diversity was computed by the Shannon index (H'. We recorded 13,892 individuals (among 20 families, 40 genera and 60 species, of which 11,530 (among 50 species germinated ex situ and 2,362 (among 34 species germinated in situ. The family Cyperaceae had the highest number of species (16, followed by Poaceae (10. The dominant species, in situ and ex situ, were Schoenoplectus juncoides (IV=47.4% and Ludwigia octovalvis (IV=34.8%, respectively. Floristic diversity was higher ex situ (H'=2.66. The information obtained here could help determine the infestation potential of these species, which could lead to improved management strategies.

  14. Epigenetic changes and transposon reactivation in Thai rice hybrids. Molecular Breeding

    NARCIS (Netherlands)

    Kantama, L.; Junbuathong, S.; Sakulkoo, J.; Jong, de J.H.S.G.M.; Apisitwanich, S.

    2013-01-01

    Inter- or intraspecific hybridization is the first step in transferring exogenous traits to the germplasm of a recipient crop. One of the complicating factors is the occurrence of epigenetic modifications of the hybrids, which in turn can change their gene expression and phenotype. In this study we

  15. 7 CFR 457.152 - Hybrid seed corn crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... that chart is used to determine the approved yield and the claim for indemnity. Certified seed test. A warm germination test performed on clean seed according to specifications of the “Rules for Testing... germination rate of at least 80 percent as determined by a certified seed test. Shelled corn. Kernels that...

  16. Optimization of process parameters for extrusion cooking of low amylose rice flour blended with seeded banana and carambola pomace for development of minerals and fiber rich breakfast cereal.

    Science.gov (United States)

    Borah, Anjan; Lata Mahanta, Charu; Kalita, Dipankar

    2016-01-01

    The low-amylose rice flour, seeded banana (Musa balbisiana, ABB) and carambola (Averrhoa carambola L.) pomace blends were extruded to prepare ready to eat breakfast cereal in a single-screw extruder. Response surface methodology using a central composite design was used to evaluate effect of independent variables, namely blend ratio (80:10:10 - 60:30:10 of low-amylose rice flour, seeded banana and carambola pomace), screw speed (200 - 400 rpm), barrel temperature (90 - 130 (°)C) and feed moisture content (9 - 21 g/100 g, wet basis) on product responses. Quadratic polynomial equations were also obtained by multiple regression analysis. The predicted models were adequate based on lack-of-fit test and coefficient of determination obtained. The feed moisture content had critical effect on all response variables. The compromised optimal conditions obtained by numerical integration for development of extrudates were: screw speed of 350 rpm, barrel temperature of 120 (°)C, feed moisture content of 12 g/100 g and 65:25:10 of blend ratio of feed. In the optimized condition low-amylose rice blend is found to have better physicochemical properties (water absorption index of 481.79 g/100 g; water solubility index of 44.13 g/100 g) and dietary fiber content of 21.35 g/100 g respectively. The developed breakfast cereal showed considerable amount of minerals (Mg and K) and overall acceptability was found to be 7.8.

  17. Qualidade fisiológica de sementes de arroz submetidas à radiação gama Physiological quality rice seed submitted to gamma radiation

    Directory of Open Access Journals (Sweden)

    Helen Lúcia da Cruz Miranda

    2009-08-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos da radiação gama (Co60 na qualidade fisiológica de sementes de arroz. O estudo foi realizado em três ensaios. No primeiro ensaio, sementes de arroz foram irradiadas com doses de 0; 1; 2,5 e 5Gy e, para o segundo e o terceiro ensaio, as sementes foram submetidas a envelhecimento acelerado, antes da irradiação. No segundo ensaio, as sementes foram dividas em úmidas e secas após envelhecimento acelerado e, então, foram irradiadas nas doses 0; 1; 2,5 e 5Gy. No terceiro ensaio, as sementes foram secas após o envelhecimento acelerado e irradiadas com doses de 0, 10, 25 e 50Gy. Para avaliação dos efeitos fisiológicos da radiação gama, foram realizados teste de germinação - TG, índice de velocidade de germinação - IVG e crescimento de plantas (comprimento de parte aérea e sistema radicular e massa seca total, em todos os ensaios. Foram determinadas as atividades enzimáticas da fosfatase ácida e alfa amilase nas sementes secas, no segundo ensaio. Os resultados obtidos nos ensaios indicam que as doses de radiação gama estudadas não afetam a qualidade fisiológica das sementes de arroz.The objective of this research was to evaluate the effects of the gamma radiation (Co60 on the physiological quality of rice seeds. The research was carried out through three tests; in the first test rice seeds were irradiated at dosages of 0; 1; 2.5 and 5Gy, while for the second and third tests the seeds were subjected to accelerated aging before being irradiated. For the second test the seeds were divided into wet and dry and both groups subjected to accelerated aging previous to irradiation at dosages of 0; 1; 2.5 and 5Gy. For the third test the seeds were dried after being subjected to accelerated aging, and then irradiated at dosages of 0, 10, 25 and 50Gy. To assess the physiological effects of the gamma radiation, all seeds were tested for germination and their germination speed index recorded

  18. Plant Type and Its Effects on Canopy Structure at Heading Stage in Various Ecological Areas for a Two-line Hybrid Rice Combination, Liangyoupeijiu

    Directory of Open Access Journals (Sweden)

    Chuan-gen LU

    2010-09-01

    Full Text Available A two-line hybrid rice combination, Liangyoupeijiu, was used to estimate several factors of plant type, and environmental models for these factors at the heading stage were established using the data of eight ecological experimental sites in 2006 and 2007. According to climatic data from 1951 to 2005, the differences in those factors and their effects on plant canopy were analyzed for four rice cropping areas in China, including South China, the middle-lower reaches of the Yangtze River, Sichuan Basin, and river valley in Yunnan, China. The thickness of leaf layer (the distance from pulvinus of the third leaf from the top to the tip of flag leaf and distribution of leaf area could be used as candidate indices for the plant type of a rice canopy.

  19. Heterosis and combining ability of seed physiological quality traits of single cross vs. three-way sorghum hybrids

    Directory of Open Access Journals (Sweden)

    Marisol Galicia-Juárez

    2017-04-01

    Full Text Available The aim of this research was to compare genetic parameters for traits related with seed germination and seedling vigour of single cross (SCH vs. three-way (TWH sorghum hybrids. The study was conducted in a sand bed under a greenhouse; 67 genotypes (four pairs of A- and B- lines, four R- lines, 13 SCH and 42 TWH were allocated in a randomized complete blocks experimental design with three replications. Statistical analysis included ANOVA’s and Student “t” tests, while Tukey test (p £ 0.05 was applied for mean comparisons. The R-lines showed better physiological seed quality attributes than the A- and B- lines. The seed quality and heterosis values of SCH vs. that of TWH did not show significant differences (p > 0.05 for any variable; however, heterobeltiosis of SCH was higher than that of TWY for normal seedlings, dry weight of plumule and seedling emergence rate. The A2- line and R14 restorer line showed the highest GCA values in both types of hybrids. No differences (p ≤ 0.05 were found between maternal and paternal effects of the A- and B- lines involved in the male sterile cross (female parent of the TWH, except for plumule length in Line 5.

  20. Armazenamento de sementes de arroz e milho em diferentes embalagens e localidades paulistas Storage of rice and corn seeds in different containers and localities of the State of Sao Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Luiz Fernandes Razera

    1986-01-01

    Full Text Available Acondicionaram-se sementes de arroz 'IAC 1246' (Oryza sativa L. e milho 'Hmd 7974' (Zea mays L. em embalagens permeáveis ao vapor de água - pano, papel, plástico trançado 5 x 5 e 5 x 6 - e na relativamente impermeável - plástico liso, de 0,25 mm de espessura. Mantiveram-nas em condições não controladas de armazém nas localidades de Campinas e Ubatuba, testando-as quanto à umidade, germinação e vigor a cada trimestre, por 36 meses. As sementes armazenadas em Ubatuba deterioraram-se mais rapidamente, sobretudo quando acondicionadas nas embalagens permeáveis. Em Campinas, as sementes de arroz embaladas em sacos de pano mantiveram germinação acima de 80% até os quinze meses, enquanto aquelas de Ubatuba o fizeram somente até os seis meses. O acondicionamento em saco de plástico liso foi bastante vantajoso, principalmente em Ubatuba, onde, aos 15 meses, a germinação das sementes de milho foi nula quando mantidas nas outras embalagens, e de 97,5% quando no saco plástico liso. As embalagens de pano, papel, plástico trançado 5 x 5 e 5 x 6 foram semelhantes entre si na manutenção da germinação e do vigor das sementes. Os resultados obtidos salientaram a grande dificuldade ou mesmo impossibilidade do armazenamento de sementes em áreas, quentes e úmidas, como Ubatuba, a menos que haja controle da temperatura e umidade relativa do ambiente do armazém, ou mediante secagem das sementes até níveis relativamente baixos de umidade (10-11% ou menos seguida de acondicionamento em embalagem que ofereça resistência à troca de umidade. As embalagens permeáveis ao vapor de água mostraram-se bastante práticas para o armazenamento em regiões de clima mais favorável à manutenção da viabilidade das sementes.Seeds of 'IAC 1246' rice (Oryza sativa L. and 'Hmd 7974' hybrid corn (Zea mays L. were packed in water vapor permeable containers as cloth bag, paper bag 5 x 5 and 5 x 6 woven plastic bag; and in a 0.25 mm thick moisture

  1. The Improvement of Atomita-4 Rice Variety Through Gamma Rays Irradiation of F1 Seeds from Atomita-4/Ir-64 Crossing

    International Nuclear Information System (INIS)

    Lilik Harsanti; Mugiono

    2004-01-01

    Atom ita-4 rice variety was crossed with IR-64 variety in the greenhouse at the Center for Application of Isotopes and Radiation-Batan, Pasar jumat in the wet season of 1994/1995. F 1 Seeds derived from Atomita-4/IR-64 crossing were irradiated by gamma rays at of 0.2 kGy dose. F 1 seeds were grown to obtain F 2 M 2 seed, and then selection of pedigree were carried out at F 2 generation. Six mutants lines were obtained purified and screened on biotypes 1, 2 and 3 brown plant hopper and bacterial leaf blight resistance by IRRI standard screening methods. The six mutant lines were tested for their potential yield at Pusakanegara and then continued tested in yield multi location test at several locations in Indonesia. Results of the screening test to brown plant hopper showed that two mutant lines Obs-1653/PsJ and Obs-1656/PsJ were resistant to biotype 1, biotype 2 and medium resistant to biotype 3. Obs-1653/PsJ and Obs-1656/PsJ also showed resistance to bacterial leaf blight strain 3 and medium resistance to strain 4. Results in the yield multi location test showed that Obs-1653/PsJ and Obs-1656/PsJ have highest yielding potential compared to IR-64 and Memberamo varieties. Those two mutant lines were released as new varieties under the name Merauke and Kahayan in 2001 and 2003 respectively. (author)

  2. Studies on the rice seed (Oryza sativa) sensitivity to gama radiation, neutrons di-enthyl sulphate (DES) and sodium azide (SA)

    International Nuclear Information System (INIS)

    Guimaraes, E.P.

    1978-04-01

    Dry rice seeds of 'Dourado Precoce' variety were treated with gama-rays, thermal and fast neutrons, di-ethyl sulphate (DES) and sodium azide (SA). Biologial effects on survival, seedling height, plant fertility and chlorophy 11 mutation frequency were studied in the M 1 generation. The data obtained were analysed by 'independent test'. Survival was not affected by increased gama ray dosage, but by increased DES and SA dosages, as well as by SA treatments with increased solution acidity for seeds pretreated in distilled water. Seedling height was decreased with the increase of gama-ray dosage, DES concentration. SA acidity and concentration. Plant fertility was reduced drastically with higher gama-ray and neutron dosages and with high SA acidity and concentrations. The maximum chlorophy 11 mutation frequency was obtained in the SA treatment. Seeds pretreated with distilled water showed larger physiological damages in the SA treatments and higher mutation frequencies. Regarding chlorophyll mutation frequency, thermal neutrons were more efficient than gama-rays. SA was the most efficient mutagen used . DES showed lower physiological damages in the M 1 plants, but did not induce mutations in the used conditions [pt

  3. Herbicide options for effective weed management in dry direct-seeded rice under scented rice-wheat rotation of western Indo-Gangetic Plains.

    Science.gov (United States)

    Singh, Vijay; Jat, Mangi L; Ganie, Zahoor A; Chauhan, Bhagirath S; Gupta, Raj K

    2016-03-01

    Farmers' participatory field trials were conducted at Madhuban, and Taraori, the two participatory experimental sites/locations of the Cereal Systems Initiative for South Asia (CSISA), a collaborative project of IRRI and CIMMYT in Karnal district of Haryana, India, during Kharif (wet season) 2010 and 2011. This research aimed to evaluate preemergence (PRE) and postemergence (POST) herbicides for providing feasible and economically viable weed management options to farmers for predominant scented rice varieties. Treatments with pendimethalin PRE fb bispyribac-sodium + azimsulfuron POST had lower weed biomass at 45 days after sowing (DAS). At Madhuban, highest grain yield of scented basmati rice (3.43 t ha -1 ) was recorded with the sequential application of pendimethalin PRE fb bispyribac-sodium + azimsulfuron POST. However, at Taraori, yields were similar with pendimethalin or oxadiargyl PRE fb bispyribac-sodium and/or azimsulfuron POST. Applying oxadiargyl by mixing with sand onto flooded field was less effective than spray applications in non-flooded field. The benefit-cost ratio of rice crop was higher with herbicide treatments at both sites as compared with the non-treated weed-free check except single PRE and POST applications and sequential application of oxadiargyl PRE fb oxadiargyl PRE. In a separate experiment conducted at Nagla and Taraori sites, scented rice cultivars' ('CSR 30' and 'Pusa 1121') tolerance to three rates of azimsulfuron (15, 25, and 35 g ai ha -1 ) was evaluated over two years (2010 and 2011). CSR 30 (superfine, scented) was more sensitive to higher rates (35 g ai ha -1 ) of azimsulfuron as compared to Pusa 1121 (fine, scented). Crop injuries were 8 and 28% in case of CSR 30; 5 and 15% in Pusa 1121 when applied with azimsulfuron 25 and 35 g ai ha -1 , respectively. Azimsulfuron applied at 35 g ai ha -1 reduced yield in both cultivars but in CSR 30 yield reduction was twofold (11.5%) as that of Pusa 1121 (5.2%).

  4. Herbicide options for effective weed management in dry direct-seeded rice under scented rice-wheat rotation of western Indo-Gangetic Plains

    Science.gov (United States)

    Singh, Vijay; Jat, Mangi L.; Ganie, Zahoor A.; Chauhan, Bhagirath S.; Gupta, Raj K.

    2016-01-01

    Farmers' participatory field trials were conducted at Madhuban, and Taraori, the two participatory experimental sites/locations of the Cereal Systems Initiative for South Asia (CSISA), a collaborative project of IRRI and CIMMYT in Karnal district of Haryana, India, during Kharif (wet season) 2010 and 2011. This research aimed to evaluate preemergence (PRE) and postemergence (POST) herbicides for providing feasible and economically viable weed management options to farmers for predominant scented rice varieties. Treatments with pendimethalin PRE fb bispyribac-sodium + azimsulfuron POST had lower weed biomass at 45 days after sowing (DAS). At Madhuban, highest grain yield of scented basmati rice (3.43 t ha−1) was recorded with the sequential application of pendimethalin PRE fb bispyribac-sodium + azimsulfuron POST. However, at Taraori, yields were similar with pendimethalin or oxadiargyl PRE fb bispyribac-sodium and/or azimsulfuron POST. Applying oxadiargyl by mixing with sand onto flooded field was less effective than spray applications in non-flooded field. The benefit-cost ratio of rice crop was higher with herbicide treatments at both sites as compared with the non-treated weed-free check except single PRE and POST applications and sequential application of oxadiargyl PRE fb oxadiargyl PRE. In a separate experiment conducted at Nagla and Taraori sites, scented rice cultivars' ('CSR 30′ and 'Pusa 1121′) tolerance to three rates of azimsulfuron (15, 25, and 35 g ai ha−1) was evaluated over two years (2010 and 2011). CSR 30 (superfine, scented) was more sensitive to higher rates (35 g ai ha−1) of azimsulfuron as compared to Pusa 1121 (fine, scented). Crop injuries were 8 and 28% in case of CSR 30; 5 and 15% in Pusa 1121 when applied with azimsulfuron 25 and 35 g ai ha−1, respectively. Azimsulfuron applied at 35 g ai ha−1 reduced yield in both cultivars but in CSR 30 yield reduction was twofold (11.5%) as that of Pusa 1121 (5.2%). PMID

  5. Mutation in Rice Abscisic Acid2 Results in Cell Death, Enhanced Disease-Resistance, Altered Seed Dormancy and Development

    Directory of Open Access Journals (Sweden)

    Yongxiang Liao

    2018-03-01

    Full Text Available Lesion mimic mutants display spontaneous cell death, and thus are valuable for understanding the molecular mechanism of cell death and disease resistance. Although a lot of such mutants have been characterized in rice, the relationship between lesion formation and abscisic acid (ABA synthesis pathway is not reported. In the present study, we identified a rice mutant, lesion mimic mutant 9150 (lmm9150, exhibiting spontaneous cell death, pre-harvest sprouting, enhanced growth, and resistance to rice bacterial and blast diseases. Cell death in the mutant was accompanied with excessive accumulation of H2O2. Enhanced disease resistance was associated with cell death and upregulation of defense-related genes. Map-based cloning identified a G-to-A point mutation resulting in a D-to-N substitution at the amino acid position 110 of OsABA2 (LOC_Os03g59610 in lmm9150. Knock-out of OsABA2 through CRISPR/Cas9 led to phenotypes similar to those of lmm9150. Consistent with the function of OsABA2 in ABA biosynthesis, ABA level in the lmm9150 mutant was significantly reduced. Moreover, exogenous application of ABA could rescue all the mutant phenotypes of lmm9150. Taken together, our data linked ABA deficiency to cell death and provided insight into the role of ABA in rice disease resistance.

  6. Mutation in Rice Abscisic Acid2 Results in Cell Death, Enhanced Disease-Resistance, Altered Seed Dormancy and Development.

    Science.gov (United States)

    Liao, Yongxiang; Bai, Que; Xu, Peizhou; Wu, Tingkai; Guo, Daiming; Peng, Yongbin; Zhang, Hongyu; Deng, Xiaoshu; Chen, Xiaoqiong; Luo, Ming; Ali, Asif; Wang, Wenming; Wu, Xianjun

    2018-01-01

    Lesion mimic mutants display spontaneous cell death, and thus are valuable for understanding the molecular mechanism of cell death and disease resistance. Although a lot of such mutants have been characterized in rice, the relationship between lesion formation and abscisic acid (ABA) synthesis pathway is not reported. In the present study, we identified a rice mutant, lesion mimic mutant 9150 ( lmm9150 ), exhibiting spontaneous cell death, pre-harvest sprouting, enhanced growth, and resistance to rice bacterial and blast diseases. Cell death in the mutant was accompanied with excessive accumulation of H 2 O 2 . Enhanced disease resistance was associated with cell death and upregulation of defense-related genes. Map-based cloning identified a G-to-A point mutation resulting in a D-to-N substitution at the amino acid position 110 of OsABA2 (LOC_Os03g59610) in lmm9150 . Knock-out of OsABA2 through CRISPR/Cas9 led to phenotypes similar to those of lmm9150 . Consistent with the function of OsABA2 in ABA biosynthesis, ABA level in the lmm9150 mutant was significantly reduced. Moreover, exogenous application of ABA could rescue all the mutant phenotypes of lmm9150 . Taken together, our data linked ABA deficiency to cell death and provided insight into the role of ABA in rice disease resistance.

  7. Molecular detection of Xanthomonas oryzae pv. oryzae, Xanthomonas oryzae pv. oryzicola, and Burkholderia glumae in infected rice seeds and leaves

    Science.gov (United States)

    Polymerase chain reaction (PCR) is particularly useful for plant pathogen detection. In the present study, multiplex PCR and SYBR green real-time PCR were developed to facilitate simultaneous detection of three important rice pathogens, Xanthomonas oryzae pv. oryzae, X. oryzae pv. oryzicola, and Bur...

  8. Allelopathic Effect of Echinochloa colona L. and Cyperus iria L. Weed Extracts on the Seed Germination and Seedling Growth of Rice and Soyabean

    Directory of Open Access Journals (Sweden)

    Neha Chopra

    2017-01-01

    Full Text Available The present study was undertaken to assess the allelopathic effect of Echinochloa colona L. and Cyperus iria L. in relation to the germination and primary growth of Oryza sativa L. (rice and Glycine max L. (soyabean. Effects of dichloromethane (DCM and double distilled water soluble (DDW fractions of E. colona L. and C. iria L. root and aerial part extracts reduced germination and suppressed early seedling growth of rice and soyabean. With increase in extract concentration from 1 to 100 mg/mL, a gradual decrease in seed germination and seedling length occurred. The highest growth of G. max seedling was recorded in DDW fraction of E. colona aerial part extract at 1 mg/mL concentration with 94% germination and the lowest length was found in DCM fraction of C. iria root extract at 100 mg/mL concentration with 65% germination. In O. sativa, the highest length was noted at 1 mg/mL concentration in DDW fraction of E. colona aerial part extract with 82% germination and the lowest length was found in DCM fraction of C. iria and E. colona root extracts with germination 57% and 62%, respectively, at 100 mg/mL concentration. The results suggested that these weeds had good allelopathic potential which reduces germination and plant growth.

  9. In Vitro Osteogenic and Odontogenic Differentiation of Human Dental Pulp Stem Cells Seeded on Carboxymethyl Cellulose-Hydroxyapatite Hybrid Hydrogel.

    Directory of Open Access Journals (Sweden)

    Gabriella eTeti

    2015-10-01

    Full Text Available Stem cells from human dental pulp have been considered as an alternative source of adult stem cells in tissue engineering because of their potential to differentiate into multiple cell lineages.Recently, polysaccharide based hydrogels have become especially attractive as matrices for the repair and regeneration of a wide variety of tissues and organs. The incorporation of inorganic minerals as hydroxyapatite nanoparticles can modulate the performance of the scaffolds with potential applications in tissue engineering. The aim of this study was to verify the osteogenic and odontogenic differentiation of dental pulp stem cells (DPSCs cultured on a carboxymethyl cellulose—hydroxyapatite hybrid hydrogel. Human DPSCs were seeded on carboxymethyl cellulose—hydroxyapatite hybrid hydrogel and on carboxymethyl cellulose hydrogel for 1, 3, 5, 7, 14 and 21 days. Cell viability assay and ultramorphological analysis were carried out to evaluate biocompatibility and cell adhesion. Real Time PCR was carried out to demonstrate the expression of osteogenic and odontogenic markers. Results showed a good adhesion and viability in cells cultured on carboxymethyl cellulose—hydroxyapatite hybrid hydrogel, while a low adhesion and viability was observed in cells cultured on carboxymethyl cellulose hydrogel. Real Time PCR data demonstrated a temporal up-regulation of osteogenic and odontogenic markers in dental pulp stem cells cultured on carboxymethyl cellulose—hydroxyapatite hybrid hydrogel. In conclusion, our in vitro data confirms the ability of DPSCs to differentiate toward osteogenic and odontogenic lineages in presence of a carboxymethyl cellulose—hydroxyapatite hybrid hydrogel. Taken together, our results provide evidence that DPSCs and carboxymethyl cellulose—hydroxyapatite hybrid hydrogel could be considered promising candidates for dental pulp complex and periodontal tissue engineering.

  10. Milk line as an indicator of the harvesting time of three hybrid seeds of corn (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Célio Trzeciak dos Santos

    2005-03-01

    Full Text Available The experiment was carried out to evaluate the time for harvesting seeds of three hybrids of corn (Zea mays L. at their best physiological quality and the use of the milk line as an indicator of the physiological seed maturity. Single hybrids CD 1723 and CD 5501 and double hybrid OC 705 seeds were collected for 59 days, every four days, starting 23 days after female flowering. Seed dry weight, moisture content, germination, vigour (cold and accelerated aging tests, black layer formation and seed milk line development were analysed. The harvesting time started 47 days after female flowering with high physiological quality of the seeds identified by a joint analysis of those seven characteristics of them. The milk line at stage 4 proved to be the best indicator of the time to harvest corn seeds for maximum physiological quality, because different stages of milk line development in corn seeds could be easily identified in the filed without any special equipment.O experimento foi conduzido durante o ano agrícola de 1996/97 em área experimental da Cooperativa de Desenvolvimento Econômico e Tecnológico (Coodetec, em Cascavel, Paraná, com o objetivo de avaliar o efeito da época de colheita de três híbridos de milho (Zea mays L. na qualidade fisiológica das sementes e o uso da linha de solidificação do endosperma como indicativo da maturidade fisiológica das sementes. O plantio foi realizado em 30 de setembro de 1996. Amostras de sementes dos híbridos simples CD 1723 e CD 5501, bem como do híbrido duplo OC 705, foram colhidas em intervalos de quatro dias, durante 59 dias, iniciando-se a colheita no vigésimo terceiro dia após o florescimento feminino. As características avaliadas nas sementes foram o acúmulo de matéria seca, o conteúdo de umidade, a germinação, o vigor (pelos testes de frio e de envelhecimento acelerado, a formação da camada preta e o desenvolvimento da linha de solidificação do endosperma. A colheita dos tr

  11. Hormonal regulation of floret closure of rice (Oryza sativa)

    Science.gov (United States)

    Huang, Youming; Zeng, Xiaochun

    2018-01-01

    Plant hormones play important roles in regulating every aspect of growth, development, and metabolism of plants. We are interested in understanding hormonal regulation of floret opening and closure in plants. This is a particularly important problem for hybrid rice because regulation of flowering time is vitally important in hybrid rice seed production. However, little was known about the effects of plant hormones on rice flowering. We have shown that jasmonate and methyl jasmonate play significant roles in promoting rice floret opening. In this study, we investigated the effects of auxins including indole-3-acidic acid (IAA), indole-3-butyric acid (IBA), 1-naphthalene-acetic acid (NAA), 2,4-dichlorophenoxy acetic acid (2,4-D) and 3,6-dichloro-2-methoxybenzoic acid (DIC) and abscisic acid (ABA) on floret closure of four fertile and three sterile varieties of rice. The results from field studies in three growing seasons in 2013–2015 showed that the percentages of closed florets were significantly lower in plants treated with IAA, IBA, 2,4-D, DIC and NAA and that the durations of floret opening were significantly longer in plants treated with the same auxins. The auxins exhibited time- and concentration-dependant effects on floret closure. ABA displayed opposite effects of auxins because it increased the percentages of floret closure and decreased the length of floret opening of rice varieties. The degree of auxin-inhibiting and ABA-promoting effects on floret closure was varied somewhat but not significantly different among the rice varieties. Endogenous IAA levels were the highest in florets collected shortly before opening followed by a sharp decline in florets with maximal angles of opening and a significant jump of IAA levels shortly after floret closure in both fertile and sterile rice plants. ABA levels showed an opposite trend in the same samples. Our results showed that auxins delayed but ABA promoted the closure of rice floret regardless of the varieties

  12. Hormonal regulation of floret closure of rice (Oryza sativa.

    Directory of Open Access Journals (Sweden)

    Youming Huang

    Full Text Available Plant hormones play important roles in regulating every aspect of growth, development, and metabolism of plants. We are interested in understanding hormonal regulation of floret opening and closure in plants. This is a particularly important problem for hybrid rice because regulation of flowering time is vitally important in hybrid rice seed production. However, little was known about the effects of plant hormones on rice flowering. We have shown that jasmonate and methyl jasmonate play significant roles in promoting rice floret opening. In this study, we investigated the effects of auxins including indole-3-acidic acid (IAA, indole-3-butyric acid (IBA, 1-naphthalene-acetic acid (NAA, 2,4-dichlorophenoxy acetic acid (2,4-D and 3,6-dichloro-2-methoxybenzoic acid (DIC and abscisic acid (ABA on floret closure of four fertile and three sterile varieties of rice. The results from field studies in three growing seasons in 2013-2015 showed that the percentages of closed florets were significantly lower in plants treated with IAA, IBA, 2,4-D, DIC and NAA and that the durations of floret opening were significantly longer in plants treated with the same auxins. The auxins exhibited time- and concentration-dependant effects on floret closure. ABA displayed opposite effects of auxins because it increased the percentages of floret closure and decreased the length of floret opening of rice varieties. The degree of auxin-inhibiting and ABA-promoting effects on floret closure was varied somewhat but not significantly different among the rice varieties. Endogenous IAA levels were the highest in florets collected shortly before opening followed by a sharp decline in florets with maximal angles of opening and a significant jump of IAA levels shortly after floret closure in both fertile and sterile rice plants. ABA levels showed an opposite trend in the same samples. Our results showed that auxins delayed but ABA promoted the closure of rice floret regardless of

  13. Deficiencies in both starch synthase IIIa and branching enzyme IIb lead to a significant increase in amylose in SSIIa-inactive japonica rice seeds.

    Science.gov (United States)

    Asai, Hiroki; Abe, Natsuko; Matsushima, Ryo; Crofts, Naoko; Oitome, Naoko F; Nakamura, Yasunori; Fujita, Naoko

    2014-10-01

    Starch synthase (SS) IIIa has the second highest activity of the total soluble SS activity in developing rice endosperm. Branching enzyme (BE) IIb is the major BE isozyme, and is strongly expressed in developing rice endosperm. A mutant (ss3a/be2b) was generated from wild-type japonica rice which lacks SSIIa activity. The seed weight of ss3a/be2b was 74-94% of that of the wild type, whereas the be2b seed weight was 59-73% of that of the wild type. There were significantly fewer amylopectin short chains [degree of polymerization (DP) ≤13] in ss3a/be2b compared with the wild type. In contrast, the amount of long chains (DP ≥25) connecting clusters of amylopectin in ss3a/be2b was higher than in the wild type and lower than in be2b. The apparent amylose content of ss3a/be2b was 45%, which was >1.5 times greater than that of either ss3a or be2b. Both SSIIIa and BEIIb deficiencies led to higher activity of ADP-glucose pyrophosphorylase (AGPase) and granule-bound starch synthase I (GBSSI), which partly explains the high amylose content in the ss3a/be2b endosperm. The percentage apparent amylose content of ss3a and ss3a/be2b at 10 days after flowering (DAF) was higher than that of the wild type and be2b. At 20 DAF, amylopectin biosynthesis in be2b and ss3a/be2b was not observed, whereas amylose biosynthesis in these lines was accelerated at 30 DAF. These data suggest that the high amylose content in the ss3a/be2b mutant results from higher amylose biosynthesis at two stages, up to 20 DAF and from 30 DAF to maturity. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  14. Electroless Sliver-Plating Process in the Preparation of 103Pd-125I Hybrid Brachytherapy Seed Cores

    Directory of Open Access Journals (Sweden)

    LI Zhong-yong1,2;CHEN Bin-da1;Lv Xiao-zhou1;LU Jin-hui1;CUI Hai-ping1,2

    2014-02-01

    Full Text Available Electroless 103Pd plating and electroless Ag plating and chemical 125I depositing were took place on the surface of carbon rods in turn, which was a reliable method for the preparation of 103Pd-125I hybrid brachytherapy seed cores. 103Pd and 125I were deposited on the same substrate effectively through silver coating as a bridge. The process of electroless Ag plating was a novel and important step in the preparation of 103Pd-125I hybrid seed. In this work, the process of electroless Ag plating was studied using 0.5×3.0 mm carbon rods with palladium coating as substrate, silver-ammino complex as precursor, 110mAg as radioactive tracer, and hydrazine as reductant. The optimum conditions were AgNO3 2g/L,Na2EDTA 40 g/L,NH3•H2O 16.25%,H4N2•H2O 5‰,pH=10,t=60 min,and T=35 ℃. Sliver deposited on each carbon rod was uniform, and sliver-coating was white and smooth.

  15. Patterns of cytosine methylation in an elite rice hybrid and its parental lines, detected by a methylation-sensitive amplification polymorphism technique.

    Science.gov (United States)

    Xiong, L Z; Xu, C G; Saghai Maroof, M A; Zhang, Q

    1999-04-01

    DNA methylation is known to play an important role in the regulation of gene expression in eukaryotes. In this study, we assessed the extent and pattern of cytosine methylation in the rice genome, using the technique of methylation-sensitive amplified polymorphism (MSAP), which is a modification of the amplified fragment length polymorphism (AFLP) method that makes use of the differential sensitivity of a pair of isoschizomers to cytosine methylation. The tissues assayed included seedlings and flag leaves of an elite rice hybrid, Shanyou 63, and the parental lines Zhenshan 97 and Minghui 63. In all, 1076 fragments, each representing a recognition site cleaved by either or both of the isoschizomers, were amplified using 16 pairs of selective primers. A total of 195 sites were found to be methylated at cytosines in one or both parents, and the two parents showed approximately the same overall degree of methylation (16.3%), as revealed by the incidence of differential digestion by the isoschizomers. Four classes of patterns were identified in a comparative assay of cytosine methylation in the parents and hybrid; increased methylation was detected in the hybrid compared to the parents at some of the recognition sites, while decreased methylation in the hybrid was detected at other sites. A small proportion of the sites was found to be differentially methylated in seedlings and flag leaves; DNA from young seedlings was methylated to a greater extent than that from flag leaves. Almost all of the methylation patterns detected by MSAP could be confirmed by Southern analysis using the isolated amplified fragments as probes. The results clearly demonstrate that the MSAP technique is highly efficient for large-scale detection of cytosine methylation in the rice genome. We believe that the technique can be adapted for use in other plant species.

  16. Breeding of early restorer Fuhui 306 and predominant performance of F1 hybrid combinations

    International Nuclear Information System (INIS)

    Wu Wanyi; Liu Yongqiang; Wu Maoli; Xue Xingqiong

    2004-01-01

    Fuhui 306, an early rice restorer with strong restoring ability, short growth period (86 days) and no restriction of separating areas in seed production, was bred by radiation treatment. F 1 hybrid combinations with different mature period were developed when cross with different sterile lines, that combination would be widely applied to meet the requirement of different ecological environment and harvest period. (authors)

  17. Evolução do banco de sementes de arroz vermelho em diferentes sistemas de utilização do solo de várzeas Red rice seed bank evolution under different systems of lowland utilization

    Directory of Open Access Journals (Sweden)

    Luis A. de Avila

    2000-08-01

    Full Text Available Num ecossistema agrícola, a redução do banco de sementes é um dos aspectos mais importantes no manejo de plantas daninhas; e em solos de várzeas, o arroz vermelho (Oryza sativa L. é atualmente considerado a principal planta daninha. Nesse sentido, conduziu-se um experimento com o objetivo de avaliar a evolução do banco de sementes de arroz vermelho no solo em diferentes sistemas de semeadura de arroz irrigado e em alternativas de manejo do solo de várzea. O experimento foi instalado em campo por dois anos consecutivos na mesma área (safras agrícolas 1996/97 e 1997/98 em Santa Maria, RS, em solo classificado como Planossolo, com infestação média de 516 sementes viáveis de arroz vermelho/m². A estimativa do banco de sementes de arroz vermelho foi realizada através de 10 coletas de solo, utilizando um cilindro com 0,10m de diâmetro a 0,10m de profundidade. Após a coleta, os grãos foram separados do solo e realizado teste de tetrazólio para determinar a quantidade de sementes viáveis na amostra. As coletas foram realizadas antes da instalação do experimento (set/1996, após a colheita do primeiro ano (mai/1997 e após a colheita do segundo ano (mai/1998. Os resultados mostraram que o cultivo do arroz no sistema convencional promove aumento no banco de sementes de arroz vermelho, enquanto que a semeadura de arroz em solo inundado (mix de pré-germinado, prégerminado ou transplante de mudas é tão eficiente na redução do banco de sementes de arroz vermelho quanto a rotação com o sorgo, o pousio do solo sem a presença de animais e também o preparo de verão.In an agricultural ecosystem, the redution of weed seed bank is of utmost importance. In lowland areas, red rice (Oryza sativa is the most important weed. Therefore, an experiment was conducted to evaluate the evolution of the red rice seed bank under different seeding systems and alternatives of soil management. The experiment was conducted during two years (1996

  18. Use of seed protein polymorphism for discrimination of improvement level and geographic origin of upland rice cultivars

    Directory of Open Access Journals (Sweden)

    Ricardo Montalván

    1998-12-01

    Full Text Available Grain proteins from 58 Brazilian and nine Japanese upland rice cultivars (Oryza sativa L. were electrophoretically separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE. Densitometric scanning of the electrophoretic profiles permitted the estimation of the relative concentration of 16 protein fractions, which were used as variables for the calculation of Fisher's canonical discriminating functions. Significant differences between mean values of protein fractions were useful in distinguishing Brazilian and Japanese cultivars, as well as improved and non-improved Brazilian rice cultivars in scattered plots. Electrophoretically detectable protein polymorphism in rice grain can indicate geographic origin as well as breeding improvement level of a cultivar. Improved cultivars were those released by plant breeding institutes.Proteínas de grão de 58 genótipos de arroz brasileiro e nove japoneses foram separadas por meio de eletroforese (SDS-PAGE. A observação densitométrica dos perfis eletroforéticos permitiu avaliar as concentrações relativas de 16 frações protéicas que foram usadas como variáveis para a estimativa de funções discriminantes de Fisher. Diferenças significantes foram encontradas entre as frações protéicas dos grupos brasileiros e japoneses, assim como entre os genótipos melhorados e não melhorados. O polimorfismo protéico detectável eletroforetica-mente nos grãos de arroz pode indicar a origem geográfica e o nível de melhoramento dos cultivares.

  19. Transgenic rice expressing a codon-modified synthetic CP4-EPSPS confers tolerance to broad-spectrum herbicide, glyphosate.

    Science.gov (United States)

    Chhapekar, Sushil; Raghavendrarao, Sanagala; Pavan, Gadamchetty; Ramakrishna, Chopperla; Singh, Vivek Kumar; Phanindra, Mullapudi Lakshmi Venkata; Dhandapani, Gurusamy; Sreevathsa, Rohini; Ananda Kumar, Polumetla

    2015-05-01

    Highly tolerant herbicide-resistant transgenic rice was developed by expressing codon-modified synthetic CP4--EPSPS. The transformants could tolerate up to 1% commercial glyphosate and has the potential to be used for DSR (direct-seeded rice). Weed infestation is one of the major biotic stress factors that is responsible for yield loss in direct-seeded rice (DSR). Herbicide-resistant rice has potential to improve the efficiency of weed management under DSR. Hence, the popular indica rice cultivar IR64, was genetically modified using Agrobacterium-mediated transformation with a codon-optimized CP4-EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) gene, with N-terminal chloroplast targeting peptide from Petunia hybrida. Integration of the transgenes in the selected rice plants was confirmed by Southern hybridization and expression by Northern and herbicide tolerance assays. Transgenic plants showed EPSPS enzyme activity even at high concentrations of glyphosate, compared to untransformed control plants. T0, T1 and T2 lines were tested by herbicide bioassay and it was confirmed that the transgenic rice could tolerate up to 1% of commercial Roundup, which is five times more in dose used to kill weeds under field condition. All together, the transgenic rice plants developed in the present study could be used efficiently to overcome weed menace.

  20. Fungal disease prevention in seedlings of rice (Oryza sativa) and other grasses by growth-promoting seed-associated endophytic bacteria from invasive Phragmites australis

    Science.gov (United States)

    Verma, Satish K.; Kingsley, Kathryn L.; Bergen, Marshall S.; Kowalski, Kurt P.; White, James F.

    2018-01-01

    Non-cultivated plants carry microbial endophytes that may be used to enhance development and disease resistance of crop species where growth-promoting and protective microbes may have been lost. During seedling establishment, seedlings may be infected by several fungal pathogens that are seed or soil borne. Several species of Fusarium, Pythium and other water moulds cause seed rots during germination. Fusariumblights of seedlings are also very common and significantly affect seedling development. In the present study we screened nine endophytic bacteria isolated from the seeds of invasive Phragmites australis by inoculating onto rice, Bermuda grass (Cynodon dactylon), or annual bluegrass (Poa annua) seeds to evaluate plant growth promotion and protection from disease caused by Fusarium oxysporum. We found that three bacteria belonging to genus Pseudomonas spp. (SLB4-P. fluorescens, SLB6-Pseudomonas sp. and SY1-Pseudomonassp.) promoted seedling development, including enhancement of root and shoot growth, and stimulation of root hair formation. These bacteria were also found to increase phosphate solubilization in in vitro experiments. Pseudomonas sp. (SY1) significantly protected grass seedlings from Fusarium infection. In co-culture experiments, strain SY1 strongly inhibited fungal pathogens with 85.71% growth inhibition of F. oxysporum, 86.33% growth inhibition of Curvularia sp. and 82.14% growth inhibition of Alternaria sp. Seedlings previously treated with bacteria were found much less infected by F. oxysporum in comparison to non-treated controls. On microscopic observation we found that bacteria appeared to degrade fungal mycelia actively. Metabolite products of strain SY1 in agar were also found to inhibit fungal growth on nutrient media. Pseudomonas sp. (SY1) was found to produce antifungal volatiles. Polymerase chain reaction (PCR) amplification using specific primers for pyrrolnitirin synthesis and HCN (hydrogen cyanide) production

  1. An Aerial Robot for Rice Farm Quality Inspection With Type-2 Fuzzy Neural Networks Tuned by Particle Swarm Optimization-Sliding Mode Control Hybrid Algorithm

    DEFF Research Database (Denmark)

    Camci, Efe; Kripalan, Devesh Raju; Ma, Linlu

    2017-01-01

    , an autonomous quality inspection over rice farms is proposed by employing quadcopters. Real-time control of these vehicles, however, is still challenging as they exhibit highly nonlinear behavior especially for agile maneuvers. What is more, these vehicles have to operate under uncertain working conditions...... particle swarm optimization-sliding mode control (PSO-SMC) theory-based hybrid algorithm is proposed for the training of T2-FNNs. In particular, continuous version of PSO is adopted for the identification of the antecedent part of T2-FNNs while SMCbased update rules are utilized for online learning...

  2. Índice de intensidade de infecção adaptado ao estudo de manchas de sementes de arroz Index of infection intensity adapted for the study of spotted rice seeds

    Directory of Open Access Journals (Sweden)

    Jaciro Soave

    1988-01-01

    Full Text Available A avaliação de manchas em amostras de sementes de arroz (Oryza sativa L. tem sido feita mediante o cálculo de porcentagem de sementes manchadas, o que não dá informação quantitativa sobre sua incidência. Com o objetivo de obter dados quantitativos de manchas de sementes de arroz, procurou-se adaptar o índice de intensidade de infecção proposto por Amaral e exemplificado por Silva, comparando-se os dois métodos. Foram utilizadas 128 amostras de 5g de sementes provenientes de ensaios conduzidos nos municípios paulistas de Jaboticabal e Pindorama, no ano agrícola de 1982/83, e compostos de 16 cultivares de arroz-de-sequeiro, com quatro repetições. Para calcular o índice de intensidade de infecção, cada amostra foi separada visualmente em quatro categorias: n0 = sem manchas; n1 = poucas manchas (até 5%; n2 = muitas manchas (6-25%, e n3 = extremamente manchadas (acima de 25% da superfície com manchas. A mesma amostra foi separada em sementes com e sem manchas, independente da quantidade de manchas que cada semente apresentasse, calculando-se a porcentagem das manchadas. A comparação da análise da variância e da correlação entre ambas as avaliações revelou que o índice de intensidade de infecção, denominado pelos autores de índice de intensidade de manchas, proporcionou maior discriminação entre os tratamentos que a porcentagem de sementes manchadas, sugerindo-o para a avaliação quantitativa de manchas de sementes de arroz.The evaluation of spots in rice seeds has been performed through the calculation of the percentage of spotted seeds. However this measurement is not quantitative. The objective of this experiment was to compare the percentage of spotted seeds with an index of infection intensity, which gives a more precise quantitative information about the extension of the seed surface area infected. For this comparison, 5g-rice-seed samples from two field trials, carried out in Jaboticabal and Pindorama, in the

  3. Development of a novel recessive genetic male sterility system for hybrid seed production in maize and other cross-pollinating crops.

    Science.gov (United States)

    Wu, Yongzhong; Fox, Tim W; Trimnell, Mary R; Wang, Lijuan; Xu, Rui-Ji; Cigan, A Mark; Huffman, Gary A; Garnaat, Carl W; Hershey, Howard; Albertsen, Marc C

    2016-03-01

    We have developed a novel hybridization platform that utilizes nuclear male sterility to produce hybrids in maize and other cross-pollinating crops. A key component of this platform is a process termed Seed Production Technology (SPT). This process incorporates a transgenic SPT maintainer line capable of propagating nontransgenic nuclear male-sterile lines for use as female parents in hybrid production. The maize SPT maintainer line is a homozygous recessive male sterile transformed with a SPT construct containing (i) a complementary wild-type male fertility gene to restore fertility, (ii) an α-amylase gene to disrupt pollination and (iii) a seed colour marker gene. The sporophytic wild-type allele complements the recessive mutation, enabling the development of pollen grains, all of which carry the recessive allele but with only half carrying the SPT transgenes. Pollen grains with the SPT transgenes exhibit starch depletion resulting from expression of α-amylase and are unable to germinate. Pollen grains that do not carry the SPT transgenes are nontransgenic and are able to fertilize homozygous mutant plants, resulting in nontransgenic male-sterile progeny for use as female parents. Because transgenic SPT maintainer seeds express a red fluorescent protein, they can be detected and efficiently separated from seeds that do not contain the SPT transgenes by mechanical colour sorting. The SPT process has the potential to replace current approaches to pollen control in commercial maize hybrid seed production. It also has important applications for other cross-pollinating crops where it can unlock the potential for greater hybrid productivity through expanding the parental germplasm pool. © 2015 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  4. Significance of rice sheath photosynthesis: Yield determination by ...

    African Journals Online (AJOL)

    Using high-yielding hybrid rice Liangyopeijiu (LYP9), its male parent 9311 and hybrid rice Shanyou 63 (SY63) as the experimental materials, the photosynthesis of rice sheath was studied by 14C radio-autography. The results showed that rice sheath could trap sunlight and produce photosynthates, and these ...

  5. Seasonal CH4 and N2O emissions and plant growth characteristics of several cultivars in direct seeded rice systems

    Science.gov (United States)

    Simmonds, M.; Anders, M. M.; Adviento-Borbe, M. A.; Van Kessel, C.; McClung, A.; Linquist, B.

    2014-12-01

    Understanding cultivar effects on field greenhouse gas (GHG) emissions in rice (Oryza sativa L.) systems is needed to improve the accuracy of predictive models used for estimating GHG emissions, and to determine to what extent choice of cultivar may have on GHG mitigation. We compared CH4 and N2O emissions, global warming potential (GWP = N2O + CH4), yield-scaled GWP (GWPY = GWP Mg-1 grain), and plant growth characteristics of 8 cultivars within 4 study sites in California and Arkansas. Seasonal CH4 emissions differed between cultivars by a factor of 2.1 and 1.3 at one California and one Arkansas site, respectively. Nitrous oxide emissions were negligible, comprised food security.

  6. Male fitness of oilseed rape (¤Brassica napus¤), weedy ¤B-rapa¤ and their F1 hybrids when pollinating ¤B-rapa¤ seeds

    DEFF Research Database (Denmark)

    Pertl, M.; Hauser, T.P.; Damgaard, C.

    2002-01-01

    The likelihood that two species hybridise and backcross may depend strongly on environmental conditions, and possibly on competitive interactions between parents and hybrids. We studied the paternity of seeds produced by weedy Brassica rapa growing in mixtures with oilseed rape (B. napus) and the...... is strongly influenced by their local frequencies, and that male fitness of F(1)hybrids, when pollinating B. rapa seeds, is low even when their female fitness (seed set) is high.......The likelihood that two species hybridise and backcross may depend strongly on environmental conditions, and possibly on competitive interactions between parents and hybrids. We studied the paternity of seeds produced by weedy Brassica rapa growing in mixtures with oilseed rape (B. napus......) and their F(1) hybrids at different frequencies and densities. Paternity was determined by the presence of a transgene, morphology, and AFLP markers. In addition, observations of flower and pollen production, and published data on pollen fertilisation success, zygote survival, and seed germination, allowed us...

  7. Study on creation and utilization of induced mutation rice materials

    International Nuclear Information System (INIS)

    Pang Aijun; Peng Weizheng; Pang Boliang; Peng Xuanming; Yang Zhen; Zhang Xianxin; Zhang Yuanhai

    2011-01-01

    60 Co γ-ray, spaceflight, laser were respectively or combinedly used to treat rice lines or hybrid materials. Many special type of seed breed lines, including high yielding ones, top quality ones, stunt stem ones, disease/pest resistent ones, colourful rices, big size of grain ones etc. were selected from the mutation materials, some were directly used as new varieties and some were indirectly used to breed hybrid varieties. All the new varieties such as 'xiangzaonuo No.1', 'xiangzaoxian No.20', 'xiangzaoxian No.21', 'xiangfu 994', 'peiliangyou 721', 'zhuliangyou 124' were popularly planted and great social and economical benefit was obtained. (authors)

  8. Carob seed germ meal as a partial soybean meal replacement in the diets of red hybrid tilapia

    Directory of Open Access Journals (Sweden)

    Abdalbast H.I. Fadel

    2017-12-01

    Full Text Available The feasibility of carob seed germ meal (CSGM as a soybean meal (SBM replacement in the diet of red tilapia hybrid was evaluated in an 8-week feeding trial. Five isonitrogenous and isocaloric diets with increasing CSGM (0, 10, 20, 30 and 40%, at the expense of SBM, were fed to triplicated groups of tilapia fingerlings. Their growth, feeding efficiency, whole body proximate composition, selected plasma biochemical parameters, and liver and gut histopathology were assessed. The survival and growth of red tilapia were unaffected by the dietary CSGM inclusion up to 30%. Growth and feeding efficiencies were significantly reduced at 40% CSGM inclusion. Hematocrit and body crude lipid were significantly lower (p < 0.05 in fish fed 30–40% CSGM while plasma ALT and protein were significantly higher compared to the control (0% CSGM. In addition, some instances of lipofuscin and cellular degradation were shown in liver while morphological changes were observed in fish fed 30 and 40% CSGM. Some of these included a 60% and 34% reduction in goblet cell prevalence and villi length, respectively, as well as a thickening of the intestinal mucosal and submucosa layers of 51 and 27%, respectively as dietary CSGM increased from 0 to 40%, that was likely due to increased anti-nutritional factors. In conclusion, a dietary inclusion of only up to 20% untreated CSGM was recommended for red hybrid tilapia.

  9. Impact of mutation breeding in rice

    International Nuclear Information System (INIS)

    Rutger, J.N.

    1992-01-01

    More cultivars have been developed in rice through the use of mutation breeding than in any other crop. Direct releases of mutants as cultivars began some 30 years ago, and now total 198 cultivars. During the last 20 years, increasing use has been made of induced mutants in cross-breeding programs, leading to 80 additional cultivars. Principal improvements through mutation breeding have been earlier maturity, short stature, and grain character modifications. Rice has been a popular subject of mutagenesis because it is the world's leading food crop, has diploid inheritance, and is highly self-pollinated. In recent years induced mutation has been exploited to develop breeding tool mutants, which are defined as mutants that in themselves may not have direct agronomic application but may be useful genetic tools for crop improvement. Examples include the eui gene, hull colour mutants, normal genetic male steriles, and environmentally sensitive genetic male steriles. The environmentally sensitive genetic male steriles, especially those in which male sterility can be turned on or off by different photoperiod lengths, show promise for simplifying hybrid rice seed production both in China and the USA. Future applications of mutation in rice include induction of unusual endosperm starch types, plant types with fewer but more productive tillers, dominant dwarfs, dominant genetic male steriles, extremely early maturing mutants, nutritional mutants, and in vitro-derived mutants for tolerance to herbicides or other growth stresses. Refs, 4 figs, 2 tabs

  10. Comportamento de cultivares de arroz irrigado em relação a fungos manchadores de sementes Performance of lowland rice cultivam to seed discoloration fungi

    Directory of Open Access Journals (Sweden)

    Jaciro Soave

    1985-01-01

    , pois foram superiores ou iguais ao controle em todos os parâmetros analisados.Aiming to detect rice seed discoloration fungi, the behavior of 37 lowland rice cultivars to each of them was determined in two field trials carried out with three replications in two sites of the State of São Paulo (Tremembé and Pindamonhangaba, Brazil, in 1980/81. Seed samples were drawn from the whole yield of each experimental plot. Spotted and spotless seeds were visually separated and discolored seed (DS% and weight loss percentages (WL% calculated. From each treatment 50 spotted and 50 spotless seeds were plated separately in Petri dishes and incubated by the blotter method. The following fungi species were detected: Alternaria sp., Cephalosporium sp., Cladosportum spp., Corynespora sp., Curvularia spp., Epicoccum spp., Fusarium moniliforme, Helminthosporium oryzae, Phoma spp., Pyricularia oryzae, Rhizoctonia solani, Rhynchosporium oryzae, Trichoconiella padwickii, Trichoderma sp. e Trichothecium sp. In relation to the number of seeds infected with each fungus, highly significant statistical differences between spotted and spotless seeds were detected for H. oryzae, Phoma spp., R. oryae and T. padwickii. They were considered as causal agents of the spots. The statistical analysis of ihe data related to each parameter showed that a variable number of cultivars out performed the commercial control, as to each respective parameter studied: 32 as to DS%; 4 as to WL%; 24 as to H. oryzae; 6 as to Phoma spp.; all cultivars as to R. oryzae and 11 as to P. padwickii. The statistical analysis of all parameters in the two sites showed the cultivars PI-1291, PI-1356, PI-1377, IR-1544, P2-S1-78, L-17-72, P2-48, P2-S2 and GI-6904-6 as the best ones when compared with the commercial control IAC-899.

  11. Live and let die - the B(sister MADS-box gene OsMADS29 controls the degeneration of cells in maternal tissues during seed development of rice (Oryza sativa.

    Directory of Open Access Journals (Sweden)

    Xuelian Yang

    Full Text Available B(sister genes have been identified as the closest relatives of class B floral homeotic genes. Previous studies have shown that B(sister genes from eudicots are involved in cell differentiation during ovule and seed development. However, the complete function of B(sister genes in eudicots is masked by redundancy with other genes and little is known about the function of B(sister genes in monocots, and about the evolution of B(sister gene functions. Here we characterize OsMADS29, one of three MADS-box B(sister genes in rice. Our analyses show that OsMADS29 is expressed in female reproductive organs including the ovule, ovule vasculature, and the whole seed except for the outer layer cells of the pericarp. Knock-down of OsMADS29 by double-stranded RNA-mediated interference (RNAi results in shriveled and/or aborted seeds. Histological analyses of the abnormal seeds at 7 days after pollination (DAP indicate that the symplastic continuity, including the ovular vascular trace and the nucellar projection, which is the nutrient source for the filial tissue at early development stages, is affected. Moreover, degeneration of all the maternal tissues in the transgenic seeds, including the pericarp, ovular vascular trace, integuments, nucellar epidermis and nucellar projection, is blocked as compared to control plants. Our results suggest that OsMADS29 has important functions in seed development of rice by regulating cell degeneration of maternal tissues. Our findings provide important insights into the ancestral function of B(sister genes.

  12. Gibberellic and kaurenoic hybrid strigolactone mimics for seed germination of parasitic weeds.

    Science.gov (United States)

    Pereira, Rondinelle G; Cala, Antonio; Fernández-Aparicio, Mónica; Molinillo, José Mg; Boaventura, Maria Ad; Macías, Francisco A

    2017-12-01

    Parasitic weeds are widespread and cause significant losses in important crops. Their germination requires the detection of crop-derived molecules such as strigolactones. Strigolactone mimics are germination-inducing molecules with the potential to apply a suicidal germination strategy for seed bank control of parasitic weeds. The D-ring, which is instrumental in the germination process of seeds of parasitic weeds, was attached to gibberellin (GA 3 ) and kaurenoic acid as the scaffold. It was shown that indeed strigolactone mimics prepared from GA 3 and kaurenoic acid are active as stimulants when a D-ring is present; some of the mimics are as active as GR24. The starting molecules were plant hormones that had previous growth-regulating activity in other organisms and the products showed enhanced activity towards parasitic weeds. The information generated may contribute to a better understanding of the germination biochemistry of the weed species used. Further research is required in this area but it is clear that the results are promising. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  13. Obtainment of sugarcane (Saccharum spp. hybrid biotechnological seed of high genetic and phytosanitary quality in Ecuador

    Directory of Open Access Journals (Sweden)

    Miguel M. Ramos-Leal

    2015-01-01

    Full Text Available Methods for obtaining healthy plants are mainly based on the combined use of meristem in vitro culture and hydrothermotherapy. This work was carried out in order to obtain free- pathogen plants for using as seeds, emphasizing ratoon stunting disease (RSD of sugarcane. The work was performed using a group of sugarcane cultivars, which was confirmed the variety identification by means of peroxidases isozymes electrophoretic patterns. Plant sanitation was performed in three successive steps by means of hydrothermal treatment at 52 oC during 2h and using the fungicide vitavax, a second hydrothermal treatment at 51 °C during 10 min to the meristem and a third step in which vitroplantlets were propagated in presence of the antibiotic gentamicin. RSD detection was done by using the staining transpiration methods (STM of functional bundles. Results allowed the creation of a germoplasm bank of sugarcane plants free of the most important systemic bacterial pathogens, with high genetic quality, which provided basic seed of excellent quality for establishing seedlings. Conservation included an in vitro-plantlets bank and the creation of a "DNA bank" which allows preserving the genetic fond in laboratory conditions. Finally a methodology for obtaining free-pathogens plants from buds and meristems is included.

  14. Genetic Basis of Variation in Rice Seed Storage Protein (Albumin, Globulin, Prolamin, and Glutelin) Content Revealed by Genome-Wide Association Analysis.

    Science.gov (United States)

    Chen, Pingli; Shen, Zhikang; Ming, Luchang; Li, Yibo; Dan, Wenhan; Lou, Guangming; Peng, Bo; Wu, Bian; Li, Yanhua; Zhao, Da; Gao, Guanjun; Zhang, Qinglu; Xiao, Jinghua; Li, Xianghua; Wang, Gongwei; He, Yuqing

    2018-01-01

    Rice seed storage protein (SSP) is an important source of nutrition and energy. Understanding the genetic basis of SSP content and mining favorable alleles that control it will be helpful for breeding new improved cultivars. An association analysis for SSP content was performed to identify underlying genes using 527 diverse Oryza sativa accessions grown in two environments. We identified more than 107 associations for five different traits, including the contents of albumin (Alb), globulin (Glo), prolamin (Pro), glutelin (Glu), and total SSP (Total). A total of 28 associations were located at previously reported QTLs or intervals. A lead SNP sf0709447538, associated for Glu content in the indica subpopulation in 2015, was further validated in near isogenic lines NIL(Zhenshan97) and NIL(Delong208), and the Glu phenotype had significantly difference between two NILs. The association region could be target for map-based cloning of the candidate genes. There were 13 associations in regions close to grain-quality-related genes; five lead single nucleotide polymorphisms (SNPs) were located less than 20 kb upstream from grain-quality-related genes ( PG5a , Wx , AGPS2a , RP6 , and, RM1 ). Several starch-metabolism-related genes ( AGPS2a , OsACS6 , PUL , GBSSII , and ISA2 ) were also associated with SSP content. We identified favorable alleles of functional candidate genes, such as RP6 , RM1 , Wx , and other four candidate genes by haplotype analysis and expression pattern. Genotypes of RP6 and RM1 with higher Pro were not identified in japonica and exhibited much higher expression levels in indica group. The lead SNP sf0601764762, repeatedly detected for Alb content in 2 years in the whole association population, was located in the Wx locus that controls the synthesis of amylose. And Alb content was significantly and negatively correlated with amylose content and the level of 2.3 kb Wx pre-mRNA examined in this study. The associations or candidate genes identified would

  15. Genetic Basis of Variation in Rice Seed Storage Protein (Albumin, Globulin, Prolamin, and Glutelin Content Revealed by Genome-Wide Association Analysis

    Directory of Open Access Journals (Sweden)

    Pingli Chen

    2018-05-01

    Full Text Available Rice seed storage protein (SSP is an important source of nutrition and energy. Understanding the genetic basis of SSP content and mining favorable alleles that control it will be helpful for breeding new improved cultivars. An association analysis for SSP content was performed to identify underlying genes using 527 diverse Oryza sativa accessions grown in two environments. We identified more than 107 associations for five different traits, including the contents of albumin (Alb, globulin (Glo, prolamin (Pro, glutelin (Glu, and total SSP (Total. A total of 28 associations were located at previously reported QTLs or intervals. A lead SNP sf0709447538, associated for Glu content in the indica subpopulation in 2015, was further validated in near isogenic lines NIL(Zhenshan97 and NIL(Delong208, and the Glu phenotype had significantly difference between two NILs. The association region could be target for map-based cloning of the candidate genes. There were 13 associations in regions close to grain-quality-related genes; five lead single nucleotide polymorphisms (SNPs were located less than 20 kb upstream from grain-quality-related genes (PG5a, Wx, AGPS2a, RP6, and, RM1. Several starch-metabolism-related genes (AGPS2a, OsACS6, PUL, GBSSII, and ISA2 were also associated with SSP content. We identified favorable alleles of functional candidate genes, such as RP6, RM1, Wx, and other four candidate genes by haplotype analysis and expression pattern. Genotypes of RP6 and RM1 with higher Pro were not identified in japonica and exhibited much higher expression levels in indica group. The lead SNP sf0601764762, repeatedly detected for Alb content in 2 years in the whole association population, was located in the Wx locus that controls the synthesis of amylose. And Alb content was significantly and negatively correlated with amylose content and the level of 2.3 kb Wx pre-mRNA examined in this study. The associations or candidate genes identified would provide

  16. In vitro Seed-dressing Technique for the Control of Seed-borne ...

    African Journals Online (AJOL)

    In vitro Seed-dressing Technique for the Control of Seed-borne Fungi of Rice variety Faro -29. ... Journal of Applied Sciences and Environmental Management ... Fernasan-D, Apron Plus 50 DS and Dithane–M45), and soaking and slurry methods at various concentrations, for the control of seed-borne fungi of rice variety

  17. Growth and Productivity of Response of Hybrid Rice to Application of Animal Manures, Plant Residues and Phosphorus

    Directory of Open Access Journals (Sweden)

    Dr. Amanullah

    2016-10-01

    Full Text Available The objective of this research was to evaluate the impact of organic sources (animal manures vs. plant residues at the rate of 10 t ha-1 each on the productivity profitability of small land rice (Oryza sativa L. grower under different levels of phosphorus (0, 30, 60 and 90 kg P ha-1 fertilization. Two separate field experiments were conducted. In experiment (1, impact of three animal manures sources (cattle, sheep & poultry manures and P levels was studied along with one control plot (no animal manure and P applied as check was investigated. In experiment (2, three plant residues sources (peach leaves, garlic residues & wheat straw and P levels was studied along with one control plot (no plant residues and P applied as check. Both the experiments were carried out on small land farmer field at District Swabi, Khyber Pakhtunkhwa Province (Northwest Pakistan during summer 2015. The results revealed that in both experiments the control plot had significantly (p≤0.05 less productivity than the average of all treated plots with organic sources and P level. The increase in P levels in both experiments (animal manure vs. plant residues had resulted in higher rice productivity (90 = 60 > 30 > 0 kg P ha-1. In the experiment under animal manures, application of poultry manure increased rice productivity as compared with sheep and cattle manures (poultry > sheep > cattle manures. In the experiment under plant residues, application of peach leaves or garlic resides had higher rice productivity over wheat straw (peach leaves = garlic residues > wheat straw. On the average, the rice grown under animal manures produced about 20% higher grain yield than the rice grown under crop residues. We concluded from this study that application of 90 kg P ha-1 along with combined application of animal manures especially poultry manure could increase rice productivity. We conclude from this study that application of 90 kg P ha-1 along with combined application of animal

  18. Uso da água por plantas híbridas ou convencionais de arroz irrigado Water use by hybrid and conventional rice plants

    Directory of Open Access Journals (Sweden)

    G. Concenço

    2009-01-01

    Full Text Available Objetivou-se com este trabalho avaliar as características associadas à eficiência do uso da água em plantas de arroz irrigado, híbridas ou convencionais. O experimento foi instalado em casa de vegetação, em delineamento experimental de blocos casualizados em esquema fatorial 2 x 6, com quatro repetições. Os tratamentos constaram de uma planta de arroz da variedade BRS Pelota (convencional ou Inov (híbrida no centro da unidade experimental, que competia com 0, 1, 2, 3, 4 ou 5 plantas da variedade BRS Pelota na periferia da unidade experimental, de acordo com o tratamento. Aos 50 DAE, foram realizadas as avaliações de massa seca da parte aérea, condutância estomática de vapores de água, temperatura da folha e taxa de transpiração, sendo calculada ainda a eficiência do uso da água pela relação entre quantidade de CO2 fixado pela fotossíntese e quantidade de água transpirada. Plantas da variedade híbrida foram superiores ou não diferiram das convencionais quanto à eficiência do uso da água.The objective of this work was to evaluate the characteristics associated to water use efficiency in hybrid or conventional rice plants. The trial was installed under greenhouse conditions, in a completely randomized block design and factorial scheme 2 x 6, with four replications. The treatments consisted of one hybrid (Inov or conventional (BRS Pelota rice plant at the center of the plot surrounded by 0, 1, 2, 3, 4, or 5 conventional (BRS Pelota plants. Fifty days after emergence, shoot dry mass, stomatal conductance of water vapor, leaf temperature and transpiration rates were evaluated, as well as water use efficiency through the relation between the photosynthesis and transpiration rates. Hybrid rice plants were superior to, or did not differ from, the conventional plants in relation to water use efficiency.

  19. Model of experimental clonal seed orchard for the production of Serbian spruce šPicea omorika /Panc./Purkyne intraspecific hybrids

    Directory of Open Access Journals (Sweden)

    Šijačić-Nikolić Mirjana

    2002-01-01

    Full Text Available The presented model for the establishment of an experimental clonal seed orchard of Serbian spruce was designed based on the results of the analysis and assessment of the genetic potential of Serbian spruce seedling seed orchard at Godovik. Based on the results of the analyses, eight superior half-sib lines of Serbian spruce were selected, of which 24 genotypes were selected. Their hybridisation, by the model of incomplete diallel cross resulted in 21 combinations at the level of half-sib lines, i.e. 48 combinations at the level of parent genotypes. The applied study methods identified the potentially valuable genotypes-cone producers i.e. pollinators, which will be fixed by cloning in the seed orchard of the second generation for the production of the promising hybrids.

  20. Comparison of the Effects of Edible Oils: Rice Bran, Grape Seed, and Canola on Serum Lipid Profile and Paraoxonase Activity in Hyperlipidemic Rats

    Directory of Open Access Journals (Sweden)

    Maryam Ranjbar-Zahedani

    2015-03-01

    Full Text Available Background: Dyslipidemia is considered as one of the crucial contributors to cardio- cerebro-vascular diseases. Objectives: The present study aimed to compare the effects of Rice Barn Oil (RBO, Grape Seed Oil (GSO, and Canola Oil (CO on dyslipidemia and oxidative stress in experimentally induced hyperlipidemic rats. Materials and Methods: In the present experimental study, forty hyperlipidemic male Wistar rats were randomly assigned to 4 groups to receive RBO, GSO, or CO or Soy Bean Oil (SBO, as controls, for 4 weeks following a 3-week period of Atherogenic Diet (AD intake. Blood samples were collected at the beginning of the study, after inducing dyslipidemia, and at the end of the experimental period. Then, the data were entered into the SPSS statistical software (v. 13.0 and analyzed using paired t-test, paired sample Wilcoxon signed rank test, and Kruskal-Wallis test. Results: AD elevated lipid and/or lipoprotein profile and decreased the paraoxonase activity in the hyperlipidemic rats. The results of paired t-test revealed that RBO led to a significant improvement in serum lipoprotein profile and paraoxonase activity. Besides, a significant difference was found in the GSO group regarding all the measured parameters, except for paraoxonase activity. Moreover, CO diet showed a significant hypolipidemic effect on serum Triglyceride (TG and Total Cholesterol (TC and led to a slight improvement in Low Density Lipoprotein-Cholesterol (LDL-C and High Density Lipoprotein-Cholesterol (HDL-C. Conclusions: The results of the present study suggested that vegetable oils, including RBO, GSO, and CO, might improve dyslipidemia and oxidative stress in hyperlipidemic rats. Indeed, substituting saturated fatty acids with unsaturated fatty acids in rats’ diet had beneficial effects on serum lipid profile and oxidative stress. Comparison of the 3 edible oils showed that GSO had a more profound effect on decreasing hyperlipidemia.

  1. Control of Rice Weevil, Sitophilus oryzae (L., in Stored Wheat Grains with Mesquite Plant, Prosopis juliflora (SW, D.C. Seed Extracts

    Directory of Open Access Journals (Sweden)

    N.H. AI-Moajel

    2004-06-01

    Full Text Available The effectiveness of mesquite plant, Prosopis juliflora (SW D.C. (Family: Mimosaceae, seed extracts against rice weevil. Sitophilus oryzae (L, reared on wheat grains was investigated in the laboratory. The tested plant extracts of P. juliflora in petroleum ether, chloroform, and acetone, effectively controlled adults and their toxicity based on LC95 and LC5O values respectively was in order: acetone (12.0, 5.8ml/kg < pet ether (8.0, 4.1ml/kg chloroform (6.3, 2.2ml/kg. A highly significant oviposition deterency effect (P< 0.05 was found for all extracts at LC50 levels, while at LC95 levels, oviposition was nearly completely inhibited. Thus, progeny emergence was completely suppressed at Legs levels, also at LCSC, of acetone extract. Chlorofonn extract indicated a slow rate of degradation alter one month of storage (90% mortality. All tested plant extracts reduced weight loss in wheat grains after 45 days of storage, but chloroform extract was the most effective. Most treatments did not significantly affect water absorption but viability was significantly reduced. Petroleum ether and chloroform extracts caused a significant inhibition effect on acetyl choline esterase (AchE in adults while acetone extract caused a significant activation effect. All three different extracts, caused a significant activation effect on phosphases (AcP and AlkP, except for chloroform and acetone extract treatments which caused significant inhibition of AcP in adults. All extracts caused a significant decrease in protein and carbohydrate contents of adults, except the carbohydrate content of adults treated with acetone extract. There was a significant increase in lipid content in adults treated with all three extracts and significant increase of carbohydrate content only in adults treated with acetone extract.

  2. genetics and inheritance of seed dormancy inflicted by seed

    African Journals Online (AJOL)

    Mgina

    ABSTRACT. The study was undertaken to investigate the genetic mode of inheritance of dormancy imposed by the hull (seed coat) in rice seeds. Freshly harvested seeds of parents, F1 and F2 populations of a cross between a dormant cultivar Kisegese and non-dormant strain K2004 were used. Germination test of the ...

  3. ANALYSIS OF SLG GENE – THE MOLECULAR MARKER IN HYBRID BREEDING OF OIL SEED RAPE

    Directory of Open Access Journals (Sweden)

    L DOLANSKÁ

    2004-07-01

    Full Text Available Oil seed rape (Brassica napus L. cultivars, donors of quality (SC and self-incompatible (SI lines have been analysed using identification of S-locus. In several Brassica napus cultivars one S-locus SLG gene was detected as dominant and the second S-locus as recessive. Amplification class II SLG gene screened recessive gene in all analysed samples (SC and SI. The DNA fragment of recessive gene corresponded to SLG gene W found in cv. Westar. S-haplotypes were analysed by PCR-RFLP. Different Brassica napus cultivars had an identical electrophoretic profile conforming with nonfunctional A10 allele in B. campestris. In B. napus A10 allele is localised in genome A. The functional recessive SLG gene is probably localised in genome C. Model of their segregation was suggested. SC and SI plants segregated in F2 generation at the ratio of approximately 3:1. This indicates a recessive monogenic disposition of SI in the experimental population.

  4. Haematological indicators in hybrid mallard ducks (Anas platyrhynchos with regard to the use of meal from whole white lupin seeds in their diet

    Directory of Open Access Journals (Sweden)

    David Zapletal

    2017-01-01

    Full Text Available The objective of our study was to assess the effect of replacing soybean meal with the meal from whole white lupin seeds (Lupinus albus of the Zulika variety in diets on selected haematological indicators in 40-day-old fattened hybrid mallard ducks. A total of 180 Cherry Valley ducks were divided into three groups (E1, E2, and control. The control group was fed a diet containing soybean meal. Soybean meal replaced with 50% and 100% meal of white lupin seeds were used in group E1 and group E2, respectively. At the end of the fattening, 12 ducks (6 males and 6 females were randomly selected from each group for a haematological examination. From the result of this study, it is clear that the effect of the diet was found only on the slightly varying number of white blood cells and on the proportion of monocytes. Ducks of group E2 showed a slight increase in the total number of leukocytes which was accompanied by a decrease in the percentage share of monocytes (P < 0.05. Based on the results, it can be claimed that the replacement of soybean meal with meal from the Zulika variety of whole white lupin seeds in the diet did not have a negative effect on the determined blood indicators. Therefore, whole white lupin seeds were successfully used as the important protein component of the diet for fattening hybrid mallard ducks.

  5. Generation and characterization of tribenuron-methyl herbicide-resistant rapeseed (Brasscia napus) for hybrid seed production using chemically induced male sterility.

    Science.gov (United States)

    Li, Haitao; Li, Juanjuan; Zhao, Bo; Wang, Jing; Yi, Licong; Liu, Chao; Wu, Jiangsheng; King, Graham J; Liu, Kede

    2015-01-01

    Identification and molecular analysis of four tribenuron-methyl resistant mutants in Brassica napus , which would be very useful in hybrid production using a Chemically induced male sterility system. Chemically induced male sterility (CIMS) systems dependent on chemical hybridization agents (CHAs) like tribenuron-methyl (TBM) represent an important approach for practical utilization of heterosis in rapeseed. However, when spraying the female parents with TBM to induce male sterility the male parents must be protected with a shield to avoid injury to the stamens, which would otherwise complicate the seed production protocol and increase the cost of hybrid seed production. Here we report the first proposed application of a herbicide-resistant cultivar in hybrid production, using a CIMS system based on identifying four TBM-resistant mutants in Brassica napus. Genetic analysis indicated that the TBM resistance was controlled by a single dominant nuclear gene. An in vitro enzyme activity assay for acetohydroxyacid synthase (AHAS) suggested that the herbicide resistance is caused by a gain-of-function mutation in a copy of AHAS genes. Comparative sequencing of the mutants and wild type BnaA.AHAS.a coding sequences identified a C-to-T transition at either position 535 or 536 from the translation start site, which resulted in a substitution of proline with serine or leucine at position 197 according to the Arabidopsis thaliana protein sequence. An allele-specific dCAPS marker developed from the C536T variation co-segregated with the herbicide resistance. Transgenic A. thaliana plants expressing BnaA.ahas3.a conferred herbicide resistance, which confirmed that the P197 substitution in BnaA.AHAS.a was responsible for the herbicide resistance. Moreover, the TBM-resistant lines maintain normal male fertility under TBM treatment and can be of practical value in hybrid seed production using CIMS.

  6. Development of labor saving operation technique by making large scale paddy field and direct seeding cultivation of rice in Tohoku district [Japan], 2: Development of technique for automatic precision laser-levelling system

    International Nuclear Information System (INIS)

    Kimura, S.; Imazono, S.; Yaji, Y.

    1999-01-01

    1) Preparation for large large paddy fields and utilization of direct rice seeding cultivation are expected to be the key technologies for the low cost and labor saving large farm rice cultivation. To achieve this, the technique of land leveling for field operations have to be developed. A precise land leveling operation by a wheel tractor with laser-beam emitter and recover in a wet paddy field are developed. 2) The automatic measurement system of a rice paddy field surface level by a tractor that we developed was highly practical. After measured data ate stored in a memory of hand-held computer the standard deviation of a field height value is shown on the display. Also, measured data are exported to the personal computer and by RC232C, the contour map of the paddy field is draw quickly, which is useful for the land leveling work. 3) Considering the relation between rice seed germination and water depth in the field, the preciseness of the field leveling for direct rice seeding is required to be under 1.5cm of standard deviation (s.d.). To realize this preciseness, a prototype leveling aparatus consisting a laser emitter, a laser receiver and dry land leveler pulled by a tracter, was developed and was tested the performance. The results of land leveling test at a field of 1 ha indicated that the elevation difference of the field of 16cm was improved to that of 92% of +- 2.5cm (1.58cm s.d.) after leveling work. The working efficiency was 0.57hour/10a. For a precise leveling work, the of the soil water content should be under the plastic limitation, under which less amount of soil adoheres to the blade of the leveler. The performance tests of the laser assisted leveling apparatus for a paddy harrowing work revealed that for an accurate operation only a blade should be controlled by a hydraulic cylinder according to a laser beam. Since large amount of soil can not be handled by the apparatus, the leveling for a paddy harrowing work is recommended for a fine leveling

  7. Research Advances in High-Yielding Cultivation and Physiology of Super Rice

    Directory of Open Access Journals (Sweden)

    Jing FU

    2012-09-01

    Full Text Available In 1996, China launched a program to breed super rice or super hybrid rice by combining intersubspecific heterosis with ideal plant types. Today, approximately 80 super rice varieties have been released and some of them show high grain yields of 12–21 t/hm2 in field experiments. The main reasons for the high yields of super rice varieties, compared with those of conventional varieties, can be summarized as follows: more spikelets per panicle and larger sink size (number of spikelets per square meter; larger leaf area index, longer duration of green leaf, greater photosynthetic rate, higher lodging resistance, greater dry matter accumulation before the heading stage, greater remobilization of pre-stored carbohydrates from stems and leaves to grains during the grain-filling period; and larger root system and greater root activity. However, there are two main problems in super rice production: poor grain-filling of the later-flowering inferior spikelets (in contrast to earlier-flowering superior spikelets, and low and unstable seed-setting rate. Here, we review recent research advances in the crop physiology of super rice, focusing on biological features, formation of yield components, and population quality. Finally, we suggest further research on crop physiology of super rice.

  8. Aplicação de zinco em sementes de arroz irrigado e no solo / Application of zinc on rice seeds and on the soil

    Directory of Open Access Journals (Sweden)

    Diniz Frouza

    2011-08-01

    Full Text Available O experimento foi conduzido em casa de vegetação do Departamento de Fitotecnia, na Universidade Federal de Santa Maria, com o objetivo de avaliar a eficiência da aplicação de zinco nas sementes da cultivar de arroz irrigado BRIRGA 410 e em sete amostras de solo, sobre altura de planta, número de afilhos e de panículas, massa fresca e seca da parte aérea e teor de zinco na massa seca da parte aérea das plantas de arroz. O delineamento experimental utilizado foi um bifatorial 4 x 7 em blocos ao acaso, com três repetições. Utilizou-se vaso de latão pintado, revestido com saco plástico, com 3,0 kg de cada solo. Os tratamentos com zinco constaram da aplicação na semente (100 g ha-1 Zn tendo como fonte ZnSO4.7H2O (22,73% de Zn, no solo (5,0 kg ha-1 Zn sendo a fonte Zincodur® (28% de Zn, as duas formas de aplicação combinadas e a testemunha sem zinco. Os resultados evidenciaram que não houve diferença estatística significativa nos tratamentos com zinco aplicado em três classes de solo e no tratamento de semente, sobre o crescimento das plantas, com exceção da variável teor de zinco na massa seca da parte aérea que foi superior para os tratamentos com zinco no solo e na semente + solo. O solo Vacacaí (PLANOSOLO HIDROMÓRFICO Eutrófico arênico, originário de São Gabriel (RS, destacou-se dentre os demais nas variáveis de números de afilhos, massa fresca e seca da parte aérea e teor de zinco na massa seca da parte aérea, pelo fato de apresentar originariamente teor mais elevado de zinco.AbstractThis experiment was conducted in the greenhouse of the Department of Plant Science, at the Federal University of Santa Maria, to evaluate the efficiency of application of zinc on the seeds of irrigated rice cultivar BR- IRGA 410 and on seven soil samples. Plant height, number of tillers, and panicle, fresh and dry shoot and zinc content in dry mass of shoots were evaluated. The experimental design used was a factorial 4 x 7 in

  9. Water culture of the rice containing Cs-137

    International Nuclear Information System (INIS)

    Choi, Yong Ho; Keum, Dong Kwon; Lim, Kwang Muk; Jun, In; Park, Doo Won

    2008-10-01

    Pot experiments were carried out in a greenhouse in order to produce Cs-137-containing rice seeds as a source material for use in manufacturing reference rice samples of a high Cs-137 activity. Two kinds of soil were used and two pots were prepared for each kind of soil. Rice plants were water-cultured in the pots and Cs-137 was applied to the surface water to induce a Cs-137 contamination of rice seeds via a plant uptake of Cs-137. Mature rice plants were harvested and Cs-137-containing rice seeds were obtained after some treatment of the harvested plants. These produced rice seeds are going to be provided for the KRISS so as to be used in manufacturing reference rice samples for Cs-137

  10. Microstructural, spectroscopic, and antibacterial properties of silver-based hybrid nanostructures biosynthesized using extracts of coriander leaves and seeds

    Directory of Open Access Journals (Sweden)

    Luna C

    2016-09-01

    Full Text Available Carlos Luna,1 Enrique Díaz Barriga-Castro,2 Alberto Gómez-Treviño,3 Nuria O Núñez,4 Raquel Mendoza-Reséndez1 1Research Center of Mathematics and Physics, Faculty of Mathematics and Physics, Autonomous University of Nuevo León, Nuevo León, Mexico; 2Central Laboratory of Analytical Instrumentation, Research Center for Applied Chemistry, Coahuila, Mexico; 3Laboratory of Molecular Biology, Faculty of Chemistry, Autonomous University of Nuevo León, Nuevo León, Mexico; 4Colloidal Materials Research Group, Institute of Materials Science of Seville, Spanish National Research Council, University of Seville, Seville, Spain Abstract: Coriander leaves and seeds have been highly appreciated since ancient times, not only due to their pleasant flavors but also due to their inhibitory activity on food degradation and their beneficial properties for health, both ascribed to their strong antioxidant activity. Recently, it has been shown that coriander leaf extracts can mediate the synthesis of metallic nanoparticles through oxidation/reduction reactions. In the present study, extracts of coriander leaves and seeds have been used as reaction media for the wet chemical synthesis of ultrafine silver nanoparticles and nanoparticle clusters, with urchin- and tree-like shapes, coated by biomolecules (mainly, proteins and polyphenols. In this greener route of nanostructure preparation, the active biocompounds of coriander simultaneously play the roles of reducing and stabilizing agents. The morphological and microstructural studies of the resulting biosynthesized silver nanostructures revealed that the nanostructures prepared with a small concentration of the precursor Ag salt (AgNO3 =5 mM exhibit an ultrafine size and a narrow size distribution, whereas particles synthesized with high concentrations of the precursor Ag salt (AgNO3 =0.5 M are polydisperse and formation of supramolecular structures occurs. Fourier transform infrared and Raman spectroscopy

  11. Plataformas de colheita e colheita manual com trilha mecânica sobre a qualidade de sementes de arroz ( Oryza sativa, L. Harvest header and manual harvest with mechanical strip on rice ( Oryza sativa, L. seeds quality

    Directory of Open Access Journals (Sweden)

    Daniel Fernandez Franco

    1999-06-01

    Full Text Available Durante a colheita do arroz irrigado ocorrem perdas e danos físicos e fisiológicos às sementes. No final da década de oitenta, surgiram as plataformas recolhedoras, que retiram ou arrancam o grão ao invés de cortar a panícula, porém, pouco se conhece a respeito dos danos físicos e fisiológicos que este sistema de plataforma pode causar às sementes. Este trabalho teve por objetivo avaliar os danos mecânicos causados às sementes dos cultivares de arroz BR-IRGA 409 e BR-IRGA 410, por três formas de colheita: (a colheita manual e trilha mecânica; (b colheita com plataforma de corte; (c colheita com plataforma recolhedora. Quando a colheita foi mecânica, realizou-se a coleta das amostras diretamente no graneleiro. O delineamento experimental foi blocos ao acaso, com seis repetições. Os resultados demonstraram que as sementes de arroz irrigado dos cultivares estudados não apresentaram diferenças significativas em suas qualidades físicas e fisiológicas, quando colhidas com plataforma de corte e com a plataforma recolhedora. Estes dois métodos de colheita, porém, apresentaram danos significativamente maiores quando comparados à colheita manual e trilha mecânica.During irrigated rice harvesting occur losses and physical and phisiological seed damage. Late 80's, appeared the strippers headers that strip the grain, instead of cutting the spike. However, little is know about physical and phisiological seed damage by harvest header. The objective of this work was to evaluate the mechanical damage caused to BR-IRGA 409 and BR-IRGA 410 rice cultivars by three harvesting methods: (a manual harvesting and mechanical strip; (b cutterbar harvesting and; (c stripper header harvesting. Samples were collected directly in the grain tank when the harvest was mechanical. The experimental design was randomized blocks with six replications. Results demonstrated that the rice seeds of the studied variety didn't showed significant differences in

  12. Long branch-chains of amylopectin with B-type crystallinity in rice seed with inhibition of starch branching enzyme I and IIb resist in situ degradation and inhibit plant growth during seedling development : Degradation of rice starch with inhibition of SBEI/IIb during seedling development.

    Science.gov (United States)

    Pan, Ting; Lin, Lingshang; Wang, Juan; Liu, Qiaoquan; Wei, Cunxu

    2018-01-08

    Endosperm starch provides prime energy for cereal seedling growth. Cereal endosperm with repression of starch branching enzyme (SBE) has been widely studied for its high resistant starch content and health benefit. However, in barley and maize, the repression of SBE changes starch component and amylopectin structure which affects grain germination and seedling establishment. A high resistant starch rice line (TRS) has been developed through inhibiting SBEI/IIb, and its starch has very high resistance to in vitro hydrolysis and digestion. However, it is unclear whether the starch resists in situ degradation in seed and influences seedling growth after grain germination. In this study, TRS and its wild-type rice cultivar Te-qing (TQ) were used to investigate the seedling growth, starch property changes, and in situ starch degradation during seedling growth. The slow degradation of starch in TRS seed restrained the seedling growth. The starch components including amylose and amylopectin were simultaneously degraded in TQ seeds during seedling growth, but in TRS seeds, the amylose was degraded faster than amylopectin and the amylopectin long branch-chains with B-type crystallinity had high resistance to in situ degradation. TQ starch was gradually degraded from the proximal to distal region of embryo and from the outer to inner in endosperm. However, TRS endosperm contained polygonal, aggregate, elongated and hollow starch from inner to outer. The polygonal starch similar to TQ starch was completely degraded, and the other starches with long branch-chains of amylopectin and B-type crystallinity were degraded faster at the early stage of seedling growth but had high resistance to in situ degradation during TRS seedling growth. The B-type crystallinity and long branch-chains of amylopectin in TRS seed had high resistance to in situ degradation, which inhibited TRS seedling growth.

  13. Interaction of genotype x management on vegetative growth and weed suppression of aerobic rice

    NARCIS (Netherlands)

    Zhao, D.L.; Bastiaans, L.; Atlin, G.N.; Spiertz, J.H.J.

    2007-01-01

    Water shortage in drought-prone rice-growing areas of the world is threatening conventional irrigated rice production systems, in which rice is transplanted into fields where standing water is maintained until harvest. Aerobic rice production systems, in which rice is grown as a direct-seeded upland

  14. Expression of hybrid fusion protein (Cry1Ac::ASAL) in transgenic rice plants imparts resistance against multiple insect pests.

    Science.gov (United States)

    Boddupally, Dayakar; Tamirisa, Srinath; Gundra, Sivakrishna Rao; Vudem, Dashavantha Reddy; Khareedu, Venkateswara Rao

    2018-05-31

    To evolve rice varieties resistant to different groups of insect pests a fusion gene, comprising DI and DII domains of Bt Cry1Ac and carbohydrate binding domain of garlic lectin (ASAL), was constructed. Transgenic rice lines were generated and evaluated to assess the efficacy of Cry1Ac::ASAL fusion protein against three major pests, viz., yellow stem borer (YSB), leaf folder (LF) and brown planthopper (BPH). Molecular analyses of transgenic plants revealed stable integration and expression of the fusion gene. In planta insect bioassays on transgenics disclosed enhanced levels of resistance compared to the control plants. High insect mortality of YSB, LF and BPH was observed on transgenics compared to that of control plants. Furthermore, honeydew assays revealed significant decreases in the feeding ability of BPH on transgenic plants as compared to the controls. Ligand blot analysis, using BPH insects fed on cry1Ac::asal transgenic rice plants, revealed a modified receptor protein-binding pattern owing to its ability to bind to additional receptors in insects. The overall results authenticate that Cry1Ac::ASAL protein is endowed with remarkable entomotoxic effects against major lepidopteran and hemipteran insects. As such, the fusion gene appears promising and can be introduced into various other crops to control multiple insect pests.

  15. Evaluation of Mechanical Properties and Morphological Studies of Rice Husk (Treated/Untreated)-CaCO3 Reinforced Epoxy Hybrid Composites

    Science.gov (United States)

    Verma, Deepak; Joshi, Garvit; Gupta, Ayush

    2016-10-01

    Natural fiber reinforced composites are a very popular area of research because of the easy availability and biodegradability of these fibers. The manufacturing of natural fiber composite is done by reinforcing fibers in the particulate form, fiber form or in woven mat form. Natural fiber composites also utilize industrial wastes as a secondary reinforcements like fly ash, sludge etc. By keeping all these point of views in the present investigation the effect of rice husk flour (chemically treated/untreated) and micro sized calcium carbonate with epoxy resin have been evaluated. The diameter of rice husk flour was maintained at 600 µm through mechanical sieving machine. The husk flour was chemically treated with NaOH (5 % w/v). Mechanical properties like hardness, flexural impact and compression strength were evaluated and found to be superior in modified or chemically treated flour as compared to unmodified or untreated flour reinforced composites. Scanning electron microscopy (SEM) study was also undertaken for the developed composites. SEM study shows the distribution of the rice husk flour and calcium carbonate over the matrix.

  16. Synergistic Exposure of Rice Seeds to Different Doses of γ-Ray and Salinity Stress Resulted in Increased Antioxidant Enzyme Activities and Gene-Specific Modulation of TC-NER Pathway

    Directory of Open Access Journals (Sweden)

    Anca Macovei

    2014-01-01

    Full Text Available Recent reports have underlined the potential of gamma (γ-rays as tools for seed priming, a process used in seed industry to increase seed vigor and to enhance plant tolerance to biotic/abiotic stresses. However, the impact of γ-rays on key aspects of plant metabolism still needs to be carefully evaluated. In the present study, rice seeds were challenged with different doses of γ-rays and grown in absence/presence of NaCl to assess the impact of these treatments on the early stages of plant life. Enhanced germination efficiency associated with increase in radicle and hypocotyl length was observed, while at later stages no increase in plant tolerance to salinity stress was evident. APX, CAT, and GR were enhanced at transcriptional level and in terms of enzyme activity, indicating the activation of antioxidant defence. The profiles of DNA damage accumulation were obtained using SCGE and the implication of TC-NER pathway in DNA damage sensing and repair mechanisms is discussed. OsXPB2, OsXPD, OsTFIIS, and OsTFIIS-like genes showed differential modulation in seedlings and plantlets in response to γ-irradiation and salinity stress. Altogether, the synergistic exposure to γ-rays and NaCl resulted in enhanced oxidative stress and proper activation of antioxidant mechanisms, thus being compatible with plant survival.

  17. 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)

  18. Microstructural characteristics, mechanical and wear behaviour of aluminium matrix hybrid composites reinforced with alumina, rice husk ash and graphite

    Directory of Open Access Journals (Sweden)

    Kenneth Kanayo Alaneme

    2015-09-01

    Full Text Available The microstructural characteristics, mechanical and wear behaviour of Aluminium matrix hybrid composites reinforced with alumina, rice husk ash (RHA and graphite were investigated. Alumina, RHA and graphite mixed in varied weight ratios were utilized to prepare 10 wt% hybrid reinforced Al-Mg-Si alloy based composites using two-step stir casting. Hardness, tensile properties, scanning electron microscopy, and wear tests were used to characterize the composites produced. The results show that Hardness decreases with increase in the weight ratio of RHA and graphite in the composites; and with RHA content greater than 50%, the effect of graphite on the hardness becomes less significant. The tensile strength for the composites containing o.5wt% graphite and up to 50% RHA was observed to be higher than that of the composites without graphite. The toughness values for the composites containing 0.5wt% graphite were in all cases higher than that of the composites without graphite. The % Elongation for all composites produced was within the range of 10–13% and the values were invariant to the RHA and graphite content. The tensile fracture surface morphology in all the composites produced was identical characterized with the presence of reinforcing particles housed in ductile dimples. The composites without graphite exhibited greater wear susceptibility in comparison to the composite grades containing graphite. However the wear resistance decreased with increase in the graphite content from 0.5 to 1.5 wt%.

  19. Cell fusion as a tool for rice improvement

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Y; Kyozuka, J; Terada, R; Nishibayashi, S; Shimamoto, K [Plantech Research Institute, Kamoshida, Midori-ku, Yokohama (Japan)

    1990-01-01

    Full text: Cell fusion offers a unique opportunity to hybridize sexually incompatible species and to mix cytoplasmic genomes in higher plants. Recent progress in plant regeneration from rice protoplasts facilitates an evaluation of the cell fusion method for rice improvement. By using electrofusion of protoplasts, we obtained hybrid/cybrid plants of the following combinations: Hybrids of rice x barnyard grass (E. oryzicola); Hybrids of rice x wild Oryza species; Cybrids of rice with transferred cms cytoplasm. For the latter, protoplasts irradiated with 70 krad x-rays were used. (author)

  20. Comparison of Moringa stenopetala seed extract as a clean coagulant with Alum and Moringa stenopetala-Alum hybrid coagulant to remove direct dye from Textile Wastewater.

    Science.gov (United States)

    Dalvand, Arash; Gholibegloo, Elham; Ganjali, Mohammad Reza; Golchinpoor, Najmeh; Khazaei, Mohammad; Kamani, Hossein; Hosseini, Sara Sadat; Mahvi, Amir Hossein

    2016-08-01

    In this study, the efficiency of Moringa stenopetala seed extract was compared with alum and M. stenopetala-alum hybrid coagulant to remove Direct Red 23 azo dye from textile wastewater. The effects of parameters such as pH, coagulant dose, type of salt used for the extraction of coagulant and initial dye concentration on dye removal efficiency were investigated. Moreover, the existing functional groups on the structure of M. stenopetala coagulant (MSC) were determined by Fourier transform infrared spectroscopy, and the morphology of sludge produced by MSC, alum, and hybrid coagulant was characterized by scanning electron microscopy. Ninhydrin test was also used to determine the quantity of primary amines in the MSC and Moringa oleifera coagulant (MOC). According to the results, with increasing the coagulant dose and decreasing the initial dye concentration, dye removal efficiency has increased. The maximum dye removal of 98.5, 98.2, and 98.3 % were obtained by using 240, 120, and 80 mg/L MSC, alum and hybrid coagulant at pH 7, respectively. The results also showed MSC was much more effective than MOC for dye removal. The volume of sludge produced by MSC was one fourth and half of those produced by alum and hybrid coagulant, respectively. Based on the results, hybrid coagulant was the most efficient coagulant for direct dye removal from colored wastewater.

  1. Development of new semidwarf sources for rice with different cytoplasms (CV Basmati 370 and Gloria)

    Energy Technology Data Exchange (ETDEWEB)

    Deus, J E; Suarez, E [Instituto de Investigaciones del Arroz, Bauta, Havana (Cuba); Fuentes, J L; Alvarez, A; Padron, E [Centro de Estudios Aplicados al Desarrollo Nuclear, Miramar, Playa, Havana (Cuba)

    2001-05-01

    In Cuba semidwarf rice varieties grow on 98% of the area. Virtually all carry the same Dee-geo-won-gen dwarfing gene. Also, most if not all the cultivars have the same cytoplasm. The induced mutations approach was undertaken in order to generate alternative genetic sources of dwarfing with different cytoplasms and to improve the grain quality of Cuban rice. The seeds of two varieties, Basmati 370 and Gloria, were irradiated with 200 and 300 Gy of {sup 60}Co gamma rays. In several generations of selection, progeny testing and preliminary yield tests 10 mutants (6 from Basmati 370 and 4 from Gloria), whose yields exceeded the source cultivars, have been advanced to replicated yield trials. Some of the mutant lines are also resistant to lodging and to blast (Pyricularis grisea). It is concluded the induced mutations can be used successfully to improve plant type and other agronomic traits in rice. The induced mutants will be used also in hybridization programs. (author)

  2. Development of new semidwarf sources for rice with different cytoplasms (CV Basmati 370 and Gloria)

    International Nuclear Information System (INIS)

    Deus, J.E.; Suarez, E.; Fuentes, J.L.; Alvarez, A.; Padron, E.

    2001-01-01

    In Cuba semidwarf rice varieties grow on 98% of the area. Virtually all carry the same Dee-geo-won-gen dwarfing gene. Also, most if not all the cultivars have the same cytoplasm. The induced mutations approach was undertaken in order to generate alternative genetic sources of dwarfing with different cytoplasms and to improve the grain quality of Cuban rice. The seeds of two varieties, Basmati 370 and Gloria, were irradiated with 200 and 300 Gy of 60 Co gamma rays. In several generations of selection, progeny testing and preliminary yield tests 10 mutants (6 from Basmati 370 and 4 from Gloria), whose yields exceeded the source cultivars, have been advanced to replicated yield trials. Some of the mutant lines are also resistant to lodging and to blast (Pyricularis grisea). It is concluded the induced mutations can be used successfully to improve plant type and other agronomic traits in rice. The induced mutants will be used also in hybridization programs. (author)

  3. The ascorbate peroxidase APX1 is a direct target of a zinc finger transcription factor ZFP36 and a late embryogenesis abundant protein OsLEA5 interacts with ZFP36 to co-regulate OsAPX1 in seed germination in rice.

    Science.gov (United States)

    Huang, Liping; Jia, Jing; Zhao, Xixi; Zhang, MengYao; Huang, Xingxiu; E Ji; Ni, Lan; Jiang, Mingyi

    2018-01-01

    Seed germination is a vital developmental process. Abscisic acid (ABA) is an essential repressor of seed germination, while ROS (reactive oxygen species) also plays a vital role in regulating seed germination. ABA could inhibit the production of ROS in seed germination, but the mechanism of ABA reduced ROS production in seed germination was hitherto unknown. Here, by ChIP (chromatin immunoprecipitation)-seq, we found that ZFP36, a rice zinc finger transcription factor, could directly bind to the promoter of OsAPX1, coding an ascorbate peroxidase (APX) which has the most affinity for H 2 O 2 (substrate; a type of ROS), and act as a transcriptional activator of OsAPX1 promoter. Moreover, ZFP36 could interact with a late embryogenesis abundant protein OsLEA5 to co-regulate the promoter activity of OsAPX1. The seed germination is highly inhibited in ZFP36 overexpression plants under ABA treatment, while an RNA interference (RNAi) mutant of OsLEA5 rice seeds were less sensitive to ABA, and exogenous ASC (ascorbate acid) could alleviate the inhibition induced by ABA. Thus, our conclusion is that OsAPX1 is a direct target of ZFP36 and OsLEA5 could interact with ZFP36 to co-regulate ABA-inhibited seed germination by controlling the expression of OsAPX1. Copyright © 2017. Published by Elsevier Inc.

  4. Detection of Alien Oryza punctata Kotschy Chromosomes in Rice, Oryza sativa L., by Genomic in situ Hybridization

    OpenAIRE

    Yasui, Hideshi; Nonomura, Ken-ichi; Iwata, Nobuo; 安井, 秀; 野々村, 賢一; 岩田, 伸夫

    1997-01-01

    Genomic in situ hybridization (GIS H) using total Oryza punctata Kotschy genomic DNA as a probe was applied to detect alien chromosomes transferred from O. punctata (W1514: 2n=2x=24: BB) to O. sativa Japonica cultivar, Nipponbare (2n=2x=24: AA). Only 12 chromosomes in the interspecific hybrids (2n=3x=36: AAB) between autotetraploid of O. sativa cultivar Nipponbare and a diploid strain of O. punctata (W1514) showed intense staining by FITC in mitotic metaphase spreads. Only one homologous pair...

  5. Adaptação do método contínuo de secagem para sementes de arroz Adaptation of the continuous drying method for rice seeds

    Directory of Open Access Journals (Sweden)

    Walter Araujo Motta

    1999-01-01

    Full Text Available Com o objetivo de avaliar a influência da adaptação do método contínuo de secagem sobre a qualidade das sementes de arroz durante o armazenamento, quatro porções de sementes, pesando cada uma 2500 kg, foram secadas em secador de fluxo contínuo Kepler Weber, modelo KW-2, utilizando diferentes temperaturas do ar, respectivamente, nas câmaras de secagem, superior e inferior: 60/40ºC; 60/50ºC; 70/50º C; 70/60ºC e um tratamento testemunha, constituído por quatro amostras submetidas à secagem estacionária em estufa regulada à temperatura constante de 32ºC. A qualidade das sementes foi avaliada através dos seguintes testes: grau de umidade, germinação, envelhecimento artificial e emergência em campo, conduzidos em quatro épocas, correspondentes aos 0, 60, 120 e 180 dias de armazenamento em condições ambientais não controladas. Os componentes do beneficiamento industrial foram determinados na primeira época de avaliação. Os resultados obtidos permitiram concluir que lotes de sementes de arroz com alta porcentagem de grãos quebrados podem apresentar elevada qualidade fisiológica; na secagem contínua adaptada, as sementes de arroz podem ser submetidas a temperaturas do ar de até 60ºC e 50ºC, respectivamente, nas câmaras superior e inferior, apesar de causar redução acentuada na porcentagem de grãos inteiros.To evaluate the effects of the adaptation of the continuous drying method on seed quality during storage, four portions of rice seeds of 2500 kg each, were dried, in a continuous flow dryer KW-2 Kepler Weber, using different temperatures in the upper and lower drying chambers: 60/40ºC; 60/50ºC; 70/50º C; 70/60ºC. As control, four samples were submitted to stationary drying in oven at 32ºC. Seed quality was evaluated through moisture content, germination, accelerated aging and field emergence tests, at the 0, 60, 120 and 180 days of storage, at room temperature. The industrial processing components were

  6. Impact of mutation breeding in rice. A review

    Energy Technology Data Exchange (ETDEWEB)

    Rutger, J N [Department of Agriculture, Stoneville, MS (United States). Agricultural Research Service

    1992-07-01

    More cultivars have been developed in rice through the use of mutation breeding than in any other crop. Direct releases of mutants as cultivars began some 30 years ago, and now total 198 cultivars. During the last 20 years, increasing use has been made of induced mutants in cross-breeding programs, leading to 80 additional cultivars. Principal improvements through mutation breeding have been earlier maturity, short stature, and grain character modifications. Rice has been a popular subject of mutagenesis because it is the world`s leading food crop, has diploid inheritance, and is highly self-pollinated. In recent years induced mutation has been exploited to develop breeding tool mutants, which are defined as mutants that in themselves may not have direct agronomic application but may be useful genetic tools for crop improvement. Examples include the eui gene, hull colour mutants, normal genetic male steriles, and environmentally sensitive genetic male steriles. The environmentally sensitive genetic male steriles, especially those in which male sterility can be turned on or off by different photoperiod lengths, show promise for simplifying hybrid rice seed production both in China and the USA. Future applications of mutation in rice include induction of unusual endosperm starch types, plant types with fewer but more productive tillers, dominant dwarfs, dominant genetic male steriles, extremely early maturing mutants, nutritional mutants, and in vitro-derived mutants for tolerance to herbicides or other growth stresses. Refs, 4 figs, 2 tabs.

  7. Effects of water management practices on residue decomposition and degradation of Cry1Ac protein from crop-wild Bt rice hybrids and parental lines during winter fallow season.

    Science.gov (United States)

    Xiao, Manqiu; Dong, Shanshan; Li, Zhaolei; Tang, Xu; Chen, Yi; Yang, Shengmao; Wu, Chunyan; Ouyang, Dongxin; Fang, Changming; Song, Zhiping

    2015-12-01

    Rice is the staple diet of over half of the world's population and Bacillus thuringiensis (Bt) rice expressing insecticidal Cry proteins is ready for deployment. An assessment of the potential impact of Bt rice on the soil ecosystem under varied field management practices is urgently required. We used litter bags to assess the residue (leaves, stems and roots) decomposition dynamics of two transgenic rice lines (Kefeng6 and Kefeng8) containing stacked genes from Bt and sck (a modified CpTI gene encoding a cowpea trypsin inhibitor) (Bt/CpTI), a non-transgenic rice near-isoline (Minghui86), wild rice (Oryza rufipogon) and crop-wild Bt rice hybrid under contrasting conditions (drainage or continuous flooding) in the field. No significant difference was detected in the remaining mass, total C and total N among cultivars under aerobic conditions, whereas significant differences in the remaining mass and total C were detected between Kefeng6 and Kefeng8 and Minghui86 under the flooded condition. A higher decomposition rate constant (km) was measured under the flooded condition compared with the aerobic condition for leaf residues, whereas the reverse was observed for root residues. The enzyme-linked immunosorbent assay (ELISA), which was used to monitor the changes in the Cry1Ac protein in Bt rice residues, indicated that (1) the degradation of the Cry1Ac protein under both conditions best fit first-order kinetics, and the predicted DT50 (50% degradation time) of the Cry1Ac protein ranged from 3.6 to 32.5 days; (2) the Cry1Ac protein in the residue degraded relatively faster under aerobic conditions; and (3) by the end of the study (~154 days), the protein was present at a low concentration in the remaining residues under both conditions. The degradation rate constant was negatively correlated with the initial carbon content and positively correlated with the initial Cry1Ac protein concentration, but it was only correlated with the mass decomposition rate constants under

  8. Radiochemical studies on radiocontaminated rice cropped in Niigata Prefecture in 1954

    Energy Technology Data Exchange (ETDEWEB)

    Nagasawa, K; Kawashiro, I; Kawamura, S; Takenaka, Y; Nishizaki, S

    1955-01-01

    Radioactivity of various parts of rice seeds cropped in 1954 was detailed and compared with that of 1953. Radioactivity due to /sup 40/K was established as total count of the ash and was subtracted for correction. None of rice seeds in 1953 showed excess radioactivity. With the seeds in 1954 the following results were obtained: unhulled rice 3 to 6 c.p.m./g; chaff 3 to 6 c.p.m./2 g; unpolished rice 0 to 0.3 c.p.m./8 g; polished rice 0; rice bran 0. This radioactivity is thought to come from the rain, adherent to the chaff, but not from soil contamination.

  9. HARVEST TIME AND PHYSIOLOGIC QUALITY OF SEEDS IN IRRIGATED RICE (Oryza sativa cv. BRS RORAIMA ÉPOCA DE COLHEITA E QUALIDADE FISIOLÓGICA DE SEMENTES EM ARROZ IRRIGADO (Oryza sativa cv. BRS RORAIMA

    Directory of Open Access Journals (Sweden)

    Oscar José Smiderle

    2008-09-01

    Full Text Available

    Harvest time is one of most important factors influencing rice seed characteristics for purpose of either planting or milling. With the objective to determine a proper harvesting  time, irrigated rice seeds of cultivar BRS Roraima were harvested at 15, 22, 29, 36, 43 and 50 days after flowering (DAF, and assessed according to humidity, viability, dry mass of 1,000 seeds, whole grain yield, productivity and storability. Seeds harvested 29 DAF showed high quality and its productivity was equivalent to the subsequent periods. Seeds harvested 50 DAF showed good performance, except for whole grain yield. Harvests 15 and 22 DAF were unsuitable, reducing the physiologic quality of seeds, mill efficiency and high initial humidity. The adequate harvest time for cultivar BRS Roraima is between 29 and 43 DAF, when seeds present higher yield, dry mass, whole grain yield, physiologic quality and storability.

    KEY-WORDS: Physiologic quality; whole grain; humidity.

    A época de colheita é um dos fatores mais importantes que influenciam as características da semente de arroz, seja para semeadura ou para consumo. Com o objetivo de determinar a época adequada de colheita de arroz irrigado, para a cultivar BRS Roraima, sementes foram colhidas aos 15, 22, 29, 36, 43 e 50 dias após o florescimento (DAF e avaliadas quanto à umidade, viabilidade, massa seca de 1.000 sementes, rendimento de grãos inteiros, produtividade e armazenabilidade. As sementes colhidas aos 29 DAF

  10. Mapped clone and functional analysis of leaf-color gene Ygl7 in a rice hybrid (Oryza sativa L. ssp. indica).

    Science.gov (United States)

    Deng, Xiao-juan; Zhang, Hai-qing; Wang, Yue; He, Feng; Liu, Jin-ling; Xiao, Xiao; Shu, Zhi-feng; Li, Wei; Wang, Guo-huai; Wang, Guo-liang

    2014-01-01

    Leaf-color is an effective marker to identify the hybridization of rice. Leaf-color related genes function in chloroplast development and the photosynthetic pigment biosynthesis of higher plants. The ygl7 (yellow-green leaf 7) is a mutant with spontaneous yellow-green leaf phenotype across the whole lifespan but with no change to its yield traits. We cloned gene Ygl7 (Os03g59640) which encodes a magnesium-chelatase ChlD protein. Expression of ygl7 turns green-leaves to yellow, whereas RNAi-mediated silence of Ygl7 causes a lethal phenotype of the transgenic plants. This indicates the importance of the gene for rice plant. On the other hand, it corroborates that ygl7 is a non-null mutants. The content of photosynthetic pigment is lower in Ygl7 than the wild type, but its light efficiency was comparatively high. All these results indicated that the mutational YGL7 protein does not cause a complete loss of original function but instead acts as a new protein performing a new function. This new function partially includes its preceding function and possesses an additional feature to promote photosynthesis. Chl1, Ygl98, and Ygl3 are three alleles of the OsChlD gene that have been documented previously. However, mutational sites of OsChlD mutant gene and their encoded protein products were different in the three mutants. The three mutants have suppressed grain output. In our experiment, plant materials of three mutants (ygl7, chl1, and ygl98) all exhibited mutational leaf-color during the whole growth period. This result was somewhat different from previous studies. We used ygl7 as female crossed with chl1 and ygl98, respectively. Both the F1 and F2 generation display yellow-green leaf phenotype with their chlorophyll and carotenoid content falling between the values of their parents. Moreover, we noted an important phenomenon: ygl7-NIL's leaf-color is yellow, not yellowy-green, and this is also true of all back-crossed offspring with ygl7.

  11. Mapped clone and functional analysis of leaf-color gene Ygl7 in a rice hybrid (Oryza sativa L. ssp. indica.

    Directory of Open Access Journals (Sweden)

    Xiao-juan Deng

    Full Text Available Leaf-color is an effective marker to identify the hybridization of rice. Leaf-color related genes function in chloroplast development and the photosynthetic pigment biosynthesis of higher plants. The ygl7 (yellow-green leaf 7 is a mutant with spontaneous yellow-green leaf phenotype across the whole lifespan but with no change to its yield traits. We cloned gene Ygl7 (Os03g59640 which encodes a magnesium-chelatase ChlD protein. Expression of ygl7 turns green-leaves to yellow, whereas RNAi-mediated silence of Ygl7 causes a lethal phenotype of the transgenic plants. This indicates the importance of the gene for rice plant. On the other hand, it corroborates that ygl7 is a non-null mutants. The content of photosynthetic pigment is lower in Ygl7 than the wild type, but its light efficiency was comparatively high. All these results indicated that the mutational YGL7 protein does not cause a complete loss of original function but instead acts as a new protein performing a new function. This new function partially includes its preceding function and possesses an additional feature to promote photosynthesis. Chl1, Ygl98, and Ygl3 are three alleles of the OsChlD gene that have been documented previously. However, mutational sites of OsChlD mutant gene and their encoded protein products were different in the three mutants. The three mutants have suppressed grain output. In our experiment, plant materials of three mutants (ygl7, chl1, and ygl98 all exhibited mutational leaf-color during the whole growth period. This result was somewhat different from previous studies. We used ygl7 as female crossed with chl1 and ygl98, respectively. Both the F1 and F2 generation display yellow-green leaf phenotype with their chlorophyll and carotenoid content falling between the values of their parents. Moreover, we noted an important phenomenon: ygl7-NIL's leaf-color is yellow, not yellowy-green, and this is also true of all back-crossed offspring with ygl7.

  12. Comparing the Bio-Hydrogen Production Potential of Pretreated Rice Straw Co-Digested with Seeded Sludge Using an Anaerobic Bioreactor under Mesophilic Thermophilic Conditions

    Directory of Open Access Journals (Sweden)

    Asma Sattar

    2016-03-01

    Full Text Available Three common pretreatments (mechanical, steam explosion and chemical used to enhance the biodegradability of rice straw were compared on the basis of bio-hydrogen production potential while co-digesting rice straw with sludge under mesophilic (37 °C and thermophilic (55 °C temperatures. The results showed that the solid state NaOH pretreatment returned the highest experimental reduction of LCH (lignin, cellulose and hemi-cellulose content and bio-hydrogen production from rice straw. The increase in incubation temperature from 37 °C to 55 °C increased the bio-hydrogen yield, and the highest experimental yield of 60.6 mL/g VSremoved was obtained under chemical pretreatment at 55 °C. The time required for maximum bio-hydrogen production was found on the basis of kinetic parameters as 36 h–47 h of incubation, which can be used as a hydraulic retention time for continuous bio-hydrogen production from rice straw. The optimum pH range of bio-hydrogen production was observed to be 6.7 ± 0.1–5.8 ± 0.1 and 7.1 ± 0.1–5.8 ± 0.1 under mesophilic and thermophilic conditions, respectively. The increase in temperature was found useful for controlling the volatile fatty acids (VFA under mechanical and steam explosion pretreatments. The comparison of pretreatment methods under the same set of experimental conditions in the present study provided a baseline for future research in order to select an appropriate pretreatment method.

  13. Clustering of 18 Local Black Rice Base on Total Anthocyanin

    Directory of Open Access Journals (Sweden)

    Kristamtini Kristamtini

    2017-10-01

    Full Text Available Black rice has a high anthocyanin content in the pericarp layer, which provides a dark purple color. Anthocyanin serve as an antioxidant that control cholesterol level in the blood, prevent anemia, potentially improve the body's resistance to disease, improve damage to liver cells (hepatitis and chirrosis, prevent impaired kidney function, prevent cancer/tumors, slows down antiaging, and prevent atherosclerosis and cardiovascular disease. Exploration results at AIAT Yogyakarta, Indonesia from 2011 to 2014 obtained 18 cultivar of local black rice Indonesia. The names of the rice are related to the color (black, red or purple formed by anthocyanin deposits in the pericarp layer, seed coat or aleuron. The objective of the study was to classify several types of local black rice from explorations based on the total anthocyanin content. The study was conducted by clustering analyzing the total anthocyanin content of 18 local black rice cultivars in Indonesia. Cluster analysis of total anthocyanin content were done using SAS ver. 9.2. Clustering dendogram shows that there were 4 groups of black rice cultivars based on the total anthocyanin content. Group I consists of Melik black rice, Patalan black rice, Yunianto black rice, Muharjo black rice, Ngatijo black rice, short life of Tugiyo black rice, Andel hitam 1, Jlitheng, and Sragen black rice. Group II consists of Pari ireng, Magelang black hairy rice, Banjarnegara-Wonosobo black rice, and Banjarnegara black rice. Group III consists of NTT black rice, Magelang non hairy black rice, Sembada hitam, and longevity Tugiyo black rice. Group IV consist only one type of black rice namely Cempo ireng. The grouping result indicate the existence of duplicate names among the black rice namely Patalan with Yunianto black rice, and short life Tugiyo with Andel hitam 1 black rice.

  14. Aerobic rice mechanization: techniques for crop establishment

    Science.gov (United States)

    Khusairy, K. M.; Ayob, H.; Chan, C. S.; Fauzi, M. I. Mohamed; Mohamad Fakhrul, Z. O.; Shahril Shah, G. S. M.; Azlan, O.; Rasad, M. A.; Hashim, A. M.; Arshad, Z.; E, E. Ibrahim; Saifulizan, M. N.

    2015-12-01

    Rice being the staple food crops, hundreds of land races in it makes the diversity of rice crops. Aerobic rice production was introduced which requires much less water input to safeguard and sustain the rice production and conserve water due to decreasing water resources, climatic changes and competition from urban and industrial users. Mechanization system plays an important role for the success of aerobic rice cultivation. All farming activities for aerobic rice production are run on aerobic soil conditions. Row seeder mechanization system is developed to replace conventional seeding technique on the aerobic rice field. It is targeted for small and the large scale aerobic rice farmers. The aero - seeder machine is used for the small scale aerobic rice field, while the accord - seeder is used for the large scale aerobic rice field. The use of this mechanization machine can eliminate the tedious and inaccurate seeding operations reduce labour costs and increases work rate. The machine is easy to operate and it can increase crop establishment rate. It reduce missing hill, increasing planting and crop with high yield can be produce. This machine is designed for low costs maintenance and it is easy to dismantle and assemble during maintenance and it is safe to be used.

  15. a survey of rice production and processing in south east nigeria

    African Journals Online (AJOL)

    user

    agricultural policy makers device the modalities for improving rice production and processing in the area. ... farmers in the South-Eastern Nigeria use manual labour in the seed bed preparation ... Rice is a very important grain food to the world.

  16. Rice microstructure

    Science.gov (United States)

    An understanding of plant structure is desirable to obtain a clear idea of the overall impact of a crop. A mature rice plant consists of leafy components (left in the field post-harvest) and paddy rice (collected). The rice plant is supported by a hollow stem (culm) with leaf sheaths attached to nod...

  17. Comparative studies of drying methods on the seed quality of ...

    African Journals Online (AJOL)

    Seed moisture content (MC) is a key component that determines storability of germplasm conserved in seed genebanks. The purpose of this research was to compare the efficiency of sun-, shade-, silica geland conventional room drying in terms of rice seed MC and viability using seeds of two interspecific progenies ...

  18. Transgene Flow from Glufosinate-Resistant Rice to Improved and Weedy Rice in China

    Directory of Open Access Journals (Sweden)

    Yong-liang LU

    2014-09-01

    Full Text Available The development of transgenic rice with novel traits in China can increase rice productivity, but transgene flow to improved or weedy rice has become a major concern. We aimed to evaluate the potential maximum frequencies of transgene flow from glufosinate-resistant rice to improved rice cultivars and weedy rice. Treatments were arranged in randomized complete blocks with three replicates. Experiments were conducted between 2009 and 2010 at the Center for Environmental Safety Supervision and Inspection for Genetically Modified Plants, China National Rice Research Institute, Hangzhou, China. Glufosinate-resistant japonica rice 99-1 was the pollen donor. The pollen recipients were two inbred japonica rice (Chunjiang 016 and Xiushui 09, two inbred indica rice (Zhongzu 14 and Zhongzao 22, two indica hybrid rice (Zhongzheyou 1 and Guodao 1, and one weedy indica rice (Taizhou weedy rice. The offspring of recipients were planted in the field and sprayed with a commercial dose of glufosinate. Leaf tissues of survivors were analyzed by polymerase chain reaction to detect the presence of the transgene. The frequency of gene flow ranged from 0 to 0.488%. In 2009, the order of gene flow frequency was as follows: weedy rice > Chunjiang 016 > Xiushui 09 and Zhongzu 14 > Guodao 1, Zhongzheyou 1 and Zhongzao 22. Gene flow frequencies were generally higher in 2009 than in 2010, but did not differ significantly among rice materials. Gene flow frequency was the highest in weedy rice followed by the inbred japonica rice. The risk of gene flow differed significantly between years and year-to-year variance could mask risk differences among pollen recipients. Gene flow was generally lesser in taller pollen recipients than in shorter ones, but plant height only accounted for about 30% of variation in gene flow. When flowering synchrony was maximized, as in this study, low frequencies of gene flow occurred from herbicide-resistant japonica rice to other cultivars and

  19. Small kernel 1 encodes a pentatricopeptide repeat protein required for mitochondrial nad7 transcript editing and seed development in maize (Zea mays) and rice (Oryza sativa).

    Science.gov (United States)

    Li, Xiao-Jie; Zhang, Ya-Feng; Hou, Mingming; Sun, Feng; Shen, Yun; Xiu, Zhi-Hui; Wang, Xiaomin; Chen, Zong-Liang; Sun, Samuel S M; Small, Ian; Tan, Bao-Cai

    2014-09-01

    RNA editing modifies cytidines (C) to uridines (U) at specific sites in the transcripts of mitochondria and plastids, altering the amino acid specified by the DNA sequence. Here we report the identification of a critical editing factor of mitochondrial nad7 transcript via molecular characterization of a small kernel 1 (smk1) mutant in Zea mays (maize). Mutations in Smk1 arrest both the embryo and endosperm development. Cloning of Smk1 indicates that it encodes an E-subclass pentatricopeptide repeat (PPR) protein that is targeted to mitochondria. Loss of SMK1 function abolishes the C → U editing at the nad7-836 site, leading to the retention of a proline codon that is edited to encode leucine in the wild type. The smk1 mutant showed dramatically reduced complex-I assembly and NADH dehydrogenase activity, and abnormal biogenesis of the mitochondria. Analysis of the ortholog in Oryza sativa (rice) reveals that rice SMK1 has a conserved function in C → U editing of the mitochondrial nad7-836 site. T-DNA knock-out mutants showed abnormal embryo and endosperm development, resulting in embryo or seedling lethality. The leucine at NAD7-279 is highly conserved from bacteria to flowering plants, and analysis of genome sequences from many plants revealed a molecular coevolution between the requirement for C → U editing at this site and the existence of an SMK1 homolog. These results demonstrate that Smk1 encodes a PPR-E protein that is required for nad7-836 editing, and this editing is critical to NAD7 function in complex-I assembly in mitochondria, and hence to embryo and endosperm development in maize and rice. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  20. Induction of male sterility in rice using chemical mutagens

    Energy Technology Data Exchange (ETDEWEB)

    Minocha, J L; Gupta, R K [Department of Genetics, Punjab Agricultural University, Ludhiana (India)

    1988-07-01

    Full text: To diversify the sources of cytoplasmic male sterility for hybrid seed production in rice (Oryza sativa L.) attempts were made to induce this character in a popular indica cultivar PR 106 through chemical mutagens. Seeds were treated with 0.4% ethidium bromide (EB) for 24 or 48h at 10 deg. C, with 0.4% ethyl methanesulphonate (EMS) for 24 or 48h at 10 deg. C for 16 hr at 20 deg. C or with 0.2% streptomycin sulphate (SM) for 24 or 48 hr at 10 deg. C. In M{sub 2} male sterile plants were detected in eleven different progenies, one from SM treatment and the remaining from EMS treatments. All the sterile plants had 100% non-stainable aborted pollen. Seed set upon open-pollination of the male sterile plants with the variety PR 106 ranged from 0.03 to 4.93 per cent whereas no seed formed in bagged panicles. In M{sub 3}, open-pollinated progenies of the male sterile plants and their fertile sibs were further studied. Two progenies segregated for male sterility, all others had only fertile plants. In one of the segregating progenies, five out of six and in the other nine out of fourteen plants were male sterile. The progenies of fertile sibs did not have any male sterile plant. The results indicate that sterility of cytoplasmic type has been induced by EMS. The parental variety PR 106 acts as the maintainer. (author)

  1. Induction of male sterility in rice using chemical mutagens

    International Nuclear Information System (INIS)

    Minocha, J.L.; Gupta, R.K.

    1988-01-01

    Full text: To diversify the sources of cytoplasmic male sterility for hybrid seed production in rice (Oryza sativa L.) attempts were made to induce this character in a popular indica cultivar PR 106 through chemical mutagens. Seeds were treated with 0.4% ethidium bromide (EB) for 24 or 48h at 10 deg. C, with 0.4% ethyl methanesulphonate (EMS) for 24 or 48h at 10 deg. C for 16 hr at 20 deg. C or with 0.2% streptomycin sulphate (SM) for 24 or 48 hr at 10 deg. C. In M 2 male sterile plants were detected in eleven different progenies, one from SM treatment and the remaining from EMS treatments. All the sterile plants had 100% non-stainable aborted pollen. Seed set upon open-pollination of the male sterile plants with the variety PR 106 ranged from 0.03 to 4.93 per cent whereas no seed formed in bagged panicles. In M 3 , open-pollinated progenies of the male sterile plants and their fertile sibs were further studied. Two progenies segregated for male sterility, all others had only fertile plants. In one of the segregating progenies, five out of six and in the other nine out of fourteen plants were male sterile. The progenies of fertile sibs did not have any male sterile plant. The results indicate that sterility of cytoplasmic type has been induced by EMS. The parental variety PR 106 acts as the maintainer. (author)

  2. Effect of different seeding methods on green manure biomass, soil ...

    African Journals Online (AJOL)

    Effect of different seeding methods on green manure biomass, soil properties and rice yield in rice-based cropping systems. ... The effects of treatments on rice yield and its components were also investigated. ... Based on the results, BBRH and PTS are good practices for production of green manure in paddy soil. Chemical ...

  3. Influence of Fungicides Application and Seed Processing on Sunflower Seed Quality

    OpenAIRE

    Šimić, Branimir; Svitlica, Brankica; Ćosić, Jasenka; Andrić, Luka; Rozman, Vlatka; Postić, Jelena; Liović, Ivica

    2009-01-01

    The aim of the research was to determine influence of methods of seed processing and application of fungicides on mass of 1000 seeds, intergrowth energy and seed germination of sunflower hybrids ‘Favorit’ and ‘Apolon’ in 2005 and 2006. Selected untreated seeds of both sunflower hybrids (control) had a minimal mass of 1000 seeds (55-59 g), intergrowth energy (18-37 %) and seed germination (39-52 %). In both years of research maximal seed quality, mass of 1000 seeds (67-69 g), intergrowth energ...

  4. Rice Seedling Substrate Produced by Coal Gangue

    Directory of Open Access Journals (Sweden)

    SHAO Yu-fei

    2017-10-01

    Full Text Available Peats are the mostly used material in making rice seedling substrate. However, mining peats could cause environmental problems. In order to reduce or replace peats in rice seedling substrate industry, this paper studied suitable way to configure rice seedling. The coal gangue was used to experiment cultivating rice. Four rice seeding experiments were carried out based on physical and chemical properties of materials attributes. The results showed:(1 Coal gangue was feasible for rice seedling; (2 The maximum adding amount of coal gangue was 80%(volume ratio though the coal gangue need to be activated; (3 In the case of no activated treatment only 38%(volume ratio of coal gangue could be added to the substrate.

  5. Main biological characters of series of mutant waxy rices developed from irradiation-induced mutation

    International Nuclear Information System (INIS)

    Huang Ronghua; Zhang Shubiao; Zhang Qingqi; Yang Rencui; Lin Jinhu

    2008-01-01

    The main biological characters of the waxy male sterile lines, maintainer lines, restorer lines and waxy hybrids which had been developed by radiation-induced mutation were studied, and the grain quality of the waxy hybrids were analyzed as well. Sesults indicated that the mutant waxy rice had the same growth duration, similar agronomic characters, panicle and spikelet traits as parent. The waxy male-sterile line had the same pollen sterility characteristic as its parent male-sterile line. The waxy hybrid rice retained the yield potential as original hybrid rice, and the grain quality of the waxy hybrids was similar to the conventional waxy rice Ejinnuo 6. (authors)

  6. Understanding the evolution of rice technology in China - from traditional agriculture to GM rice today.

    Science.gov (United States)

    Shen, Xiaobai

    2010-01-01

    This paper provides an historical survey of the evolution of rice technology in China, from the traditional farming system to genetically modified rice today. Using sociotechnological analytical framework, it analyses rice technology as a socio-technical ensemble - a complex interaction of material and social elements, and discusses the specificity of technology development and its socio-technical outcomes. It points to two imperatives in rice variety development: wholesale transporting agricultural technology and social mechanism to developing countries are likely lead to negative consequences; indigenous innovation including deploying GM technology for seed varietal development and capturing/cultivating local knowledge will provide better solutions.

  7. Iron biofortification of Myanmar rice

    Directory of Open Access Journals (Sweden)

    May Sann Aung

    2013-05-01

    Full Text Available Iron (Fe deficiency causes elevates human mortality rates, especially in developing countries. In Myanmar, the prevalence of Fe-deficient anemia in children and pregnant women are 75% and 71%, respectively. Myanmar people have one of the highest per capita rice consumption rates globally. Consequently, production of Fe-biofortified rice would likely contribute to solving the Fe-deficiency problem in this human population. To produce Fe-biofortified Myanmar rice by transgenic methods, we first analyzed callus induction and regeneration efficiencies in 15 varieties that are presently popular because of their high yields and/or qualities. Callus formation and regeneration efficiency in each variety was strongly influenced by types of culture media containing a range of 2,4-dichlorophenoxyacetic acid concentrations. The Paw San Yin variety, which has a high Fe content in polished seeds, performed well in callus induction and regeneration trials. Thus, we transformed this variety using a gene expression cassette that enhanced Fe transport within rice plants through overexpression of the nicotianamine synthase gene HvNAS1, Fe flow to the endosperm through the Fe(II-nicotianamine transporter gene OsYSL2, and Fe accumulation in endosperm by the Fe storage protein gene SoyferH2. A line with a transgene insertion was successfully obtained. Enhanced expressions of the introduced genes OsYSL2, HvNAS1, and SoyferH2 occurred in immature T2 seeds. The transformants accumulated 3.4-fold higher Fe concentrations, and also 1.3-fold higher zinc concentrations in T2 polished seeds compared to levels in non-transgenic rice. This Fe-biofortified rice has the potential to reduce Fe-deficiency anemia in millions of Myanmar people without changing food habits and without introducing additional costs.

  8. Improvement of rice starch by gamma irradiation

    International Nuclear Information System (INIS)

    Duan Zhiying; Wu Dianxing; Shen Shengquan; Han Juanying; Xia Yingwu

    2003-01-01

    Three types of rice cultivars, Indica, Japonica and hybrid rice, with similar intermediate apparent amylose content (AAC) as well as early Indica rice cultivars with different amounts of AAC were selected for studying the effects of gamma irradiation on starch viscosity, physico-chemical properties and starch granule structure. Four major parameters of RVA profile, peak viscosity (PKV), hot paste viscosity (HPV), cool paste viscosity (CPV), setback viscosity (SBV) and consistence viscosity (CSV) were considerably decreased with increasing dose levels. Gamma irradiation reduced the amylose contents in the cultivars with low AAC, intermediate AAC, and glutinous rice, but had no effects on the high AAC cultivar. No visible changes in alkali spreading value (ASV) were detected after irradiation, but the peak time (PKT) were reduced with the dose level. Gel consistency (GC) were significantly increased in the tested cultivars, especially in the high AAC Indica rice, suggesting that it is promising to use gamma irradiation to improve eating and cooking quality of rice

  9. Role of mutation in improving rice productivity-retrospect and prospect

    International Nuclear Information System (INIS)

    Chakrabarti, S.N.

    1996-01-01

    With the recent development in the hybrid rice breeding and rice biotechnology, the role of mutation induction in genetic manipulation deserves special importance. In many instances, the major constraint in hybrid rice breeding is lack of suitable cytoplasmic male sterile line. There is immense scope for developing such male sterile lines through use of mutation tool. In this paper improvement of rice productivity with particular reference to attainments in India have been discussed. 50 refs., 2 figs., 6 tabs

  10. Effects of salt stress on germination and early seedling growth of rice ...

    African Journals Online (AJOL)

    use

    2011-12-05

    Dec 5, 2011 ... the relationship between speed of germination and seed vigor, salt stress decreased seed vigor of rice cultivars LD a superior ... Key words: Salinity, seed germination, seedling property, seed vigor. INTRODUCTION ... The salt solutions were prepared based on the methods by. (Rhoades et al., 1992) with ...

  11. Rendimento do arroz e manejo da irrigação e da palha de azevém no sistema mix de pré-germinado Rice yield and management of irrigation and ryegrass straw on flooded rice in no tillage and water seed system

    Directory of Open Access Journals (Sweden)

    Eduardo González Pinto

    2003-04-01

    limiting factor in many agricultural areas, when high productivity is the objective. Alternative system of crop cultivation using no tillage on flooded water seed system can be used to minimize the problem. Although this system has technical and economical advantages on the production chain, especially on red rice control, anaerobic process of ryegrass straw decomposition may produce toxic substances to rice plants establishment. The objective of this work was to evaluate the effect of different water irrigation management and the amount of ryegrass straw on grain yield and yield components on paddy rice cultivated. The experiment was conducted in greenhouse, during the 1998/99 crop growing season, on Hidromorphy Planosoil, sandy Eutrophic, soil mapping unit "Vacacaí", over ryegrass crop residue at the Federal University of Santa Maria, Santa Maria, RS. The rice cultivar IRGA 417 was used. A completely randomized design factorial (3x3, three water management (with neither vertical nor surface in-out water flow over the soil, with drainage and surface water flow and three amount of ryegrass straw (0.0 t ha-1, 3.43 t ha-1 and 6.86 t ha-1. The data demonstrated that a permanent flooding with neither vertical nor surface in-out water flow reduce dry matter above ground and grain yield when compared to the treatments with drainage and surface in-out water flow. Increasing the amount of ryegrass straw on the no-tillage water seed system, with neither vertical nor surface in-out water flow, on the flooded water the grain yield is reduced.

  12. Synthesis composite hydrogels from inorganic-organic hybrids based on leftover rice for environment-friendly controlled-release urea fertilizers.

    Science.gov (United States)

    Zhou, Tao; Wang, Yan; Huang, Sheng; Zhao, Youcai

    2018-02-15

    Nearly 1.3 billion tons of food are discarded annually in the production process. In this study, a novel slow-release nitrogen fertilizer with water absorbency was developed using leftover rice and crosslinking methods. Urea was incorporated as the nitrogen source in a leftover rice-g-poly(acrylic acid)/montmorillonite (LR-g-PAA/MMT) network, and then the leftover rice-g-poly(acrylic acid)/montmorillonite/Urea (LR-g-PAA/MMT/Urea) retained in the soil, and used as the loss control agent for water and nutrients. Variables including concentrations of acrylic acid, montmorillonite, N,N´-methylenebis acrylamide (MBA), and potassium persulfate (KPS) were investigated. Samples were with a water absorbency of 102.6g/g in distilled water and 25.1g/g in 1.0wt% NaCl solution under optimized conditions. Swelling measurements and water-retention indicated that higher-covalent cations would aggregate the hydrogels and decrease swelling. Investigating leaching behavior showed that these samples have the potential to carry the necessary nitrogen (N). The results demonstrated that the LR-g-PAA/MMT/Urea had a low leaching losses of N (19.7%) compared with pure urea (52.3%). Therefore, the developed fertilizer may be widely applicable in agriculture and horticulture, and could provide a new platform for reusing leftover rice. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Biofortified rice with enhanced nutrition Swapan K Datta, Visva ...

    Indian Academy of Sciences (India)

    Kabari

    Low Phytate rice β-carotene + ... Preschool children. Pregnant ... maternal night blindness, based on extant ... the parental line used for anther culture .... Based on the substantial equivalence concept of OECD, the analyzed transgenic seeds.

  14. Coincidence of flowering time and the productivity and quality of cauliflower hybrid seeds Coincidência de florescimento entre linhagens de couve-flor na produtividade e qualidade de sementes híbridas

    Directory of Open Access Journals (Sweden)

    Marcelo Fontanetti Verdial

    2001-09-01

    Full Text Available The missing of flowering synchronization between the self-incompatible lines in a crop field of cauliflower hybrid seeds besides making the seed production smaller can compromise the genetic purity of them. The coincidence of the flowering time between two cauliflower lines was examined to study its effect on the productivity and quality of hybrid seeds. The treatments consisted of six different sowing dates, every fifteen days, using a self-incompatible tropical line pollinated by a winter line which does not present self-incompatibility. The following characteristics were evaluated: leaf average area and number of flowers per plant, number of siliques per plant, number and weight of seeds per plant, weight of thousand seeds and average number of seeds per silique. The germination standard test and genetic seed purity were determined for each treatment. The coincident flowering season between cauliflower lines affects directly the productivity and the genetic quality of the produced hybrid seeds. The closer the flowering time coincidence between the lines, the greater the number of seeds per silique and the smaller the percentage of non-hybrid seedlings. However, the coincidence of the flowering season between lines was found to influence physiological seed quality.A falta de sincronismo de florescimento entre as linhagens auto incompatíveis em um campo de produção de sementes híbridas de couve flor pode além de reduzir a produção de sementes comprometer a pureza genética das mesmas. Com o objetivo de estudar o efeito da coincidência de florescimento entre linhagens de couve-flor na produtividade e qualidade de sementes híbridas, foi realizado o presente experimento. Os tratamentos consistiram em seis diferentes épocas de semeadura, espaçadas a cada quinze dias, de uma linhagem de verão auto-incompatível que foi polinizada por uma linhagem de inverno que não apresenta auto-incompatibilidade. Observou-se a coincidência do

  15. The ideal harvest time for seeds of hybrid maize (Zea mays L.) XY335 and ZD958 produced in multiple environments

    OpenAIRE

    Gu, Riliang; Li, Li; Liang, Xiaolin; Wang, Yanbo; Fan, Tinglu; Wang, Ying; Wang, Jianhua

    2017-01-01

    To identify the ideal harvest time (IHT) for the seed production of XY335 and ZD958, six seed-related traits were evaluated in seeds harvested at 11 harvest stages in 8 environments. Standard germination (SG), accelerated aging germination (AAG) and cold test germination (CTG) were vigor traits; hundred-seed weight (HSW) and seed moisture content (SMC) were physiological traits; and ≥10 °C accumulated temperature from pollination to harvest (AT10ph) was an ecological trait. All the traits wer...

  16. Rice yield prediction from yield components and limiting factors

    NARCIS (Netherlands)

    Casanova, D.; Goudriaan, J.; Catala Former, M.M.; Withagen, J.C.M.

    2002-01-01

    This article aims to quantify growth at field level in relation to crop status and soil properties in irrigated direct-seeded rice. Forty fields were selected in the Ebro Delta (Spain). Rice growth was monitored and soil properties measured. Yield was related to soil properties by a deductive

  17. GINES: first rice mutant obtained from proton irradiation

    International Nuclear Information System (INIS)

    Gonzalez, Maria C; Perez, Noraida; Cristo, Elizabeth

    2009-01-01

    A new rice variety of a good productive potential and salinity tolerance was obtained at the National Institute of Agricultural Sciences (INCA), starting from in vitro culture of J-104 rice seeds irradiated with protons. This is the first report of a variety achieved by proton irradiation

  18. Phytase activity in brown rice during steeping and sprouting

    NARCIS (Netherlands)

    Ou, K.; Cheng, Y.; Xing, Y.; Lin, L.; Nout, M.J.R.; Liang, J.

    2011-01-01

    Phytase in brown rice will be activated and accumulated during seed germination. Changes of phytase activity in brown rice during two stages of germination (steeping and sprouting) affected by process conditions were studied. It was shown that steeping led to significant decrease of phytase activity

  19. 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.

  20. A virtual seed file: the use of multispectral image analysis in the management of genebank seed accessions

    DEFF Research Database (Denmark)

    Adsetts Edberg Hansen, Michael; R. Hay, Fiona; Carstensen, Jens Michael

    2015-01-01

    We present a method for multispectral seed phenotyping as a fast and robust tool for managing genebank accessions. A multispectral vision system was used to take images of the seeds of 20 diverse varieties of rice (approximately 30 seeds for each variety). This was followed by extraction of feature...

  1. Effects of partially replacing dietary soybean meal or cottonseed meal with completely hydrolyzed feather meal (defatted rice bran as the carrier) on production, cytokines, adhesive gut bacteria, and disease resistance in hybrid tilapia (Oreochromis niloticus ♀ × Oreochromis aureus ♂).

    Science.gov (United States)

    Zhang, Zhen; Xu, Li; Liu, Wenshu; Yang, Yalin; Du, Zhenyu; Zhou, Zhigang

    2014-12-01

    We formulated experimental diets for hybrid tilapia to investigate the effects of replacing dietary soybean meal (SBM) or cottonseed meal (CSM) by completely hydrolyzed feather meal (defatted rice bran as the carrier; abbreviated as CHFM), with emphasis on fish growth, the composition of adhesive gut bacteria, intestinal and hepatic immune responses, and disease resistance. A series of four isonitrogenous (33% crude protein) and isolipidic (6% crude lipid) diets were formulated to replace the isonitrogenous percentages of CSM or SBM by 6% or 12% CHFM. Quadruplicate groups of healthy and uniformly sized hybrid tilapia were assigned to each experimental diet. Fish were hand fed three times a day for 8 weeks at a rearing temperature of 25-28 °C. The growth performance of hybrid tilapia fed diets with partial replacement of dietary SBM or CSM with CHFM was comparable to the group of fish fed the control diet. The CHFM-containing diets affected the intestinal autochthonous bacterial community in similar ways. All CHFM-containing diets stimulated the expression of heat shock protein 70 in the intestine but suppressed its expression in the liver. Only the CHFM6/SBM diet stimulated the expression of interleukin-1β in intestine, and no effects were observed in all diets to the expression of interleukin-1β in liver. Thus, regarding the immune response in the intestine and liver, CHFM is a good alternative protein source that induces less stress in the host. CHFM did not affect disease resistance to Aeromonas hydrophila infection in hybrid tilapia. These data suggest that CHFM is a good alternative to partially replace SBM and CSM in tilapia feed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Decreased panicle-derived indole-3-acetic acid reduces gibberellin A1 level in the uppermost internode, causing panicle enclosure in male sterile rice Zhenshan 97A.

    Science.gov (United States)

    Yin, Changxi; Gan, Lijun; Ng, Denny; Zhou, Xie; Xia, Kai

    2007-01-01

    Cytoplasmic male sterile (CMS) rice Zhenshan 97A (ZS97A) has been widely used in hybrid rice production in China. However, ZS97A suffers from serious panicle enclosure, which blocks normal pollination and greatly reduces seed production of hybrid rice. Little is known about the cause of panicle closure in ZS97A. In this study, it was found that the occurrence of cytoplasmic male sterility caused a deficiency of indole-3-acetic acid (IAA) in ZS97A panicles, and less IAA was provided to the uppermost internode (UI). Further, it was found that the decreased panicle-derived IAA caused a gibberellin A(1) (GA(1)) deficiency in the UI by the down-regulation of OsGA3ox2 transcript level. Reduced GA(1) level in the UI led to decreases of both cell number and cell elongation, resulting in a shortened UI. The shortened UI was unable to push the panicle out of the flag leaf sheath that remained normal, which resulted in panicle enclosure in ZS97A. These findings suggest that decreased panicle-derived IAA reduces the GA(1) level in the UI, causing panicle enclosure in CMS rice ZS97A.

  3. Induction of dominant male sterility by using 60Co γ-rays irradiation in rice oryza sativa L

    International Nuclear Information System (INIS)

    Shu Qingyao; Wu Dianxing; Xia Yingwu; Gao Mingwei

    2000-01-01

    The fertility of M 1 plants, which developed from dried rice (c.v. Zhe9248) seeds treated with γ-rays at the dosage of 300 Gy, decreased dramatically, and some of the M 1 plants showed completely male sterile. There were still fertile and sterile plants in the M 2 F 1 population of artificially emasculated high sterile Zhe9248 M 1 plants crossed to normal variety G93-89, and consequently, Zhe9248 was back crossed to the sterile plants successively as recurrent parent. In all the above back cross populations, fertile and sterile plants segregated in a 1 : 1 ratio. The M 4 BC 2 male sterile plants were crossed to various rice materials, e.g. early season indica rice (Zhefu 504, H416), middle season indica rice (Chuan-si-ran-zhan, Yu-Zhan), maintainer lines (Fu-Nan B, 351 B) and restorer lines (IR36, 20964). In all the above F 1 populations, male sterile and fertile plants again segregated in a 1 : 1 ratio. In addition, sib-crossing were made in the back crosses and hybrid crosses between male sterile and fertile plants, male sterile and fertile plants appeared in a similar fashion as in test crosses. However, no male sterile plants were recovered from fertile plants either of back crosses or test crosses. The anthers of male sterile plants appeared small and poorly developed, the pollen showed typical abortion or round abortion, the seed set in bagged panicles was very low. The experimental data showed that this male sterile rice mutant was inherited in a single-gene mode

  4. Tagging of four Rf genes with selective genotyping analysis in rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Yarahmadi Saeid

    2017-01-01

    Full Text Available Wild abortive type of cytoplasmic male sterility (WA-CMS is commercially used for hybrid rice seed production. The linked markers can be used for selection of plants with desirable traits. Tagging of Rf genes was carried out using recessive and dominant class analysis in a large F2 population from the cross IR58025A×IR42686R. Pollen fertility and seed setting were evaluated at the flowering and maturity stages, respectively. Forty-seven highly sterile and 23 fertile homozygous plants were selected from F2 population for molecular marker assay. Four Rf genes identified in a good restorer line with high-quality derived from a random mating composite population at the International Rice Research Institute (IRRI. The genetic distance from Rf3 locus with flanking markers RM443 and RM315 on chromosome 1 was 3.7 and 21.2 cM, respectively. RM258, RM591, RM271 and RM6737 on the long arm of chromosome 10 were linked with the Rf6 gene with distance of 7.4, 22.6, 6 and 2.9 cM, respectively. Rf6 was flanked by RM6737 and RM591. The Rf4 gene located on chromosome 7 was linked with RM6344 at a genetic distance of 10.6 cM. RM519 and RM7003 were linked with other Rf gene on chromosome 12 at a genetic distance of 8.5 and 20.8 cM, respectively. Closely linked markers identified in this study could be used for marker assisted selection in a hybrid rice breeding program. A new Rf locus on chromosome 12 that designated Rf7 was linked with RM7003 and RM519.

  5. On-farm management practices against rice root weevil (Echinocnemus oryzae Marshall)

    OpenAIRE

    Rakesh Pandey; Ajit Kumar Chaturvedi; Rudal Prasad Chaudhary; Rajendra Prasad

    2017-01-01

    Rice is the staple food of over half the world's population and occupies almost one-fifth of the global cropland under cereals. The rice root weevil, Echinocnemus oryzae Marshall, (Coleoptera: Curculionidae) has posed a problem in paddy cultivation areas in India. The damage by this root weevil results in a significant decrease in root and shoot biomass and ultimately the yield of rice plants. Studies were conducted to test the effective management practices of rice root weevil using a seedli...

  6. Efficacy of oral immunotherapy with a rice-based edible vaccine containing hypoallergenic Japanese cedar pollen allergens for treatment of established allergic conjunctivitis in mice

    Directory of Open Access Journals (Sweden)

    Ken Fukuda

    2018-01-01

    Conclusions: Oral administration of transgenic rice seeds expressing hypoallergenic allergens ameliorated allergic conjunctivitis in the established setting. Such a rice-based edible vaccine is potentially both safe and effective for oral immunotherapy in individuals with allergic conjunctivitis.

  7. (Heckel) seeds

    African Journals Online (AJOL)

    UTILISATEUR

    Garcinia kola seeds to six different hormonal pre-germination treatments. This consisted of ... Thus, seed dormancy in this case is not a coat- imposed .... development of the cultivation of the species. The cause .... Hormonal regulation of seed ...

  8. Development of an ideal plant type and male sterility system in sesame suitable for summer rice fallow in the coastal regions of Tamil Nadu

    International Nuclear Information System (INIS)

    Ganesan, J.

    2001-01-01

    In Tamil Nadu, sesame growing on available residual soil moisture after the rice harvest is expanding. In order to achieve higher and more reliable yields under these conditions, a more suitable plant type is needed: with shorter stature and growing period, moderate basal branching and higher productivity. Seeds of 6 varieties were treated with gamma rays, diethyl sulphate (DES) and ethyl methane sulphonate (EMS). The M 1 -M 4 generations were studied and several promising mutants were selected. Among them were also male sterile mutants; it is thought that such mutants will assist in producing hybrid varieties which will give the desired yield breakthrough. (author)

  9. 7 CFR 201.78 - Pollen control for hybrids.

    Science.gov (United States)

    2010-01-01

    ... line used to pollinate an A Line and to restore fertility in the resulting hybrid seed.) (b) Corn. When 5 percent or more of the seed parent plants have receptive silks, shedding tassels in the seed...

  10. The dynamics of rice production in Indonesia 1961–2009

    Directory of Open Access Journals (Sweden)

    Dyah R. Panuju

    2013-01-01

    Full Text Available Rice is one of the important agricultural products in Indonesia. The production has been fully supported by infrastructure including research and development as well as government regulations in pricing. Its vulnerability to climate change requires adaptation strategies on irrigation, biotechnology and selection of alternative crops. The primary goal of this paper was to evaluate the historical perspective of the dynamics of rice production, technologies particularly in seed inventions, labour in farming and consumption of rice from 1961 to 2009 in conjunction with land capability. The study of historical rice production could be a benefit for future agricultural planning in Indonesia.

  11. Rice breeding with induced mutations in France

    Energy Technology Data Exchange (ETDEWEB)

    Marie, R [Station d' Amelioration des Plantes, Institut National de Recherches Agronomiques, Montpellier (France)

    1970-03-01

    Mutation experiments with rice at Montpellier yielded strains with improved lodging resistance, grain size, maturing time, milling quality and other characters. The general performance of these mutant strains was tested in field trials. Further mutagenic treatments were made to improve the high-yielding short grain varieties with regard to grain quality and seed dormancy. (author)

  12. Allelopathic potential of selected rice varieties

    African Journals Online (AJOL)

    ajl10

    2012-11-01

    Nov 1, 2012 ... 1Faculty of Agro Based Industry, Universiti Malaysia Kelantan, 17600 Jeli, Kelantan, Malaysia. ... experiment was laid out in completely randomized design. ..... Mixed-Cultures. PLoS ONE 7(5):e37201. Islam M (2010). Allelopathic effects of rice varieties on seed germination and seedling growth of lettuce.

  13. Rice genetic resources in postwar Sierra Leone

    NARCIS (Netherlands)

    Chakanda, R.T.M.

    2009-01-01

    This research presents the effect of the 10-year long civil war in Sierra Leone on rice genetic resources, using farmers and their seed systems in three selected districts as reference points. The war disrupted all forms of production and development in the country and like other sectors of the

  14. Overexpression of a New Zinc Finger Protein Transcription Factor OsCTZFP8 Improves Cold Tolerance in Rice

    Directory of Open Access Journals (Sweden)

    Yong-Mei Jin

    2018-01-01

    Full Text Available Cold stress is one of the most important abiotic stresses in rice. C2H2 zinc finger proteins play important roles in response to abiotic stresses in plants. In the present study, we isolated and functionally characterized a new C2H2 zinc finger protein transcription factor OsCTZFP8 in rice. OsCTZFP8 encodes a C2H2 zinc finger protein, which contains a typical zinc finger motif, as well as a potential nuclear localization signal (NLS and a leucine-rich region (L-box. Expression of OsCTZFP8 was differentially induced by several abiotic stresses and was strongly induced by cold stress. Subcellular localization assay and yeast one-hybrid analysis revealed that OsCTZFP8 was a nuclear protein and has transactivation activity. To characterize the function of OsCTZFP8 in rice, the full-length cDNA of OsCTZFP8 was isolated and transgenic rice with overexpression of OsCTZFP8 driven by the maize ubiquitin promoter was generated using Agrobacterium-mediated transformation. Among 46 independent transgenic lines, 6 single-copy homozygous overexpressing lines were selected by Southern blot analysis and Basta resistance segregation assay in both T1 and T2 generations. Transgenic rice overexpressing OsCTZFP8 exhibited cold tolerant phenotypes with significantly higher pollen fertilities and seed setting rates than nontransgenic control plants. In addition, yield per plant of OsCTZFP8-expressing lines was significantly (p<0.01 higher than that of nontransgenic control plants under cold treatments. These results demonstrate that OsCTZFP8 was a C2H2 zinc finger transcription factor that plays an important role in cold tolerance in rice.

  15. Whole-plant dynamic system of nitrogen use for vegetative growth and grain filling in rice plants (Oryza sativa L. as revealed through the production of 350 grains from a germinated seed over 150 days: a review and synthesis

    Directory of Open Access Journals (Sweden)

    Tadakatsu Yoneyama

    2016-08-01

    Full Text Available A single germinated rice (Oryza sativa L seed can produce 350 grains with the sequential development of 15 leaves on the main stem and 7 ‒ 10 leaves on 4 productive tillers (forming 5 panicles in total, using nitrogen (N taken up from the environment over a 150-day growing season. Nitrogen travels from uptake sites to the grain through growing organ-directed cycling among sequentially developed organs. Over the past 40 years, the dynamic system for N allocation during vegetative growth and grain filling has been elucidated through studies on N and 15N transport as well as enzymes and transporters involved. In this review, we synthesize the information obtained in these studies along the following main points: (1 During vegetative growth before grain-filling, about half of the total N in the growing organs, including young leaves, tillers, root tips and differentiating panicles is supplied via phloem from mature source organs such as leaves and roots, after turnover and remobilization of proteins, whereas the other half is newly taken up and supplied via xylem, with an efficient xylem-to-phloem transfer at stem nodes. Thus, the growth of new organs depends equally on both N sources. (2 A large fraction (as much as 80% of the grain N is derived largely from mature organs such as leaves and stems by degradation, including the autophagy pathway of chloroplast proteins (e.g., Rubisco. (3 Mobilized proteinogenic amino acids, including arginine, lysine, proline and valine, are derived mainly from protein degradation, with amino acid transporters playing a role in transferring these amino acids across cell membranes of source and sink organs, and enabling their efficient reutilization in the latter. On the other hand, amino acids such as glutamine, glutamic acid, γ-amino butyric acid, aspartic acid, and alanine are produced by assimilation of newly taken up N by roots and transported via xylem and phloem. The formation of 350 filled grains over 50

  16. PHOTOPERIOD-INDUCED POLLEN ABORTION IN PGMS RICE

    African Journals Online (AJOL)

    user

    2013-11-20

    Nov 20, 2013 ... of the Hubei Photosensitive Genic Male-sterile Rice (Oryza sativa subsp. japonica). Acta Genetica Sinica 13(2):107-112. Virmani SS (1994). Heterosis and Hybrid Rice Breeding. Monographs on Theoretical and Applied Genetics. Springer-Verlag. Berlin. Heidelberg, Germany. 22:7(1). Virmani SS (1996).

  17. Paper (essay on seed

    Directory of Open Access Journals (Sweden)

    Mirić Mladen

    2013-01-01

    Full Text Available Based on detailed studies of the past of the agrarian thought of the world (evolution of agro-innovation, and within it, the relationship of man and seed, the author has selected key data for Table 1. In addition, more or less known folk sayings, proverbs, curses and allegories in which the seed is the key word have been collected. Then, religious books, folk art and literature works (sayings of prominent individuals and experts and observations of the author himself have been studied. According to the collected opus, it can be concluded that the vast importance of seed meaningfully entwined into all spheres of folk life and cultural heritage. Seed is directly tied to the following eight key (revolutionary milestones in the food and economic life of mankind: 1. the first and for the longest time, the seed used to be the main food of the people and the first food reserve; 2. Neolithic Revolution was simply caused by the sowing of seeds; 3. for the sake of sowing man began to develop more complex processing techniques; 4. everywhere and forever, especially since the late 15th century, the seed has been a carrier of (rescuing plants between Europe and the New World, that is, between continents; 5. seed was the first product that has been chemically treated since the mid-18th century; 6. standard operation procedures and quality are promoted on seed by which it became the first product to have prescribed (compulsory methods, but it also became a good whose quality has to be tested before sale; 7. hybrid seed is a 'perpetrator' of the green revolution in the mid-20th century and at last there is disputable seed of genetically modified organisms that are spreading with certain reactions. The author proposes that the United Nations Standard International Trade Classification includes a special section (division which would classify the seed for sowing, while beyond this Classification terms such as seed, plant seed should be replaced with non-seed

  18. Analysis of rice purchase decision on rice consumer in Bandung city

    Science.gov (United States)

    Kusno, K.; Imannurdin, A.; Syamsiyah, N.; Djuwendah, E.

    2018-03-01

    This study was conducted at three kinds of purchase location which were traditional market, rice kiosk, and supermarket in Bandung City, with survey data of 108 respondents which were selected by systematic random sampling. The aim of this study is to (1) identify consumer characteristics, (2) identify which atribute is considered by consumer in buying rice, and (3) analyze the relationship between purchase decision and income class. Data were analyzed by descriptive analysis and Chi Square test. The results showed most consumers in the traditional market were middle-educated and lower middle-income, at the rice kiosk, the consumer were generally middle-educated and middle-income, and in the supermarkets, the majority were high-educated and upper middle-income consumers. “Kepulenan” be the first priority of most consumers, but for the lower-middle class, the main priority was price. Thus, in case of scarcity and rice price increase, the government should immediately arrange market operations which targeting to lower-middle class consumers. There was a significant relationship between (1) the quality