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Cesar A Dominguez - One of the best experts on this subject based on the ideXlab platform.
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Patterns of Male Sterility within and among populations of the distylous shrub Erythroxylum havanense (erythroxylaceae)
Plant Ecology, 2005Co-Authors: Eduardo Cuevas, Francisco Molina-freaner, Luis E. Eguiarte, Cesar A DominguezAbstract:Distyly, a reproductive system characterized by the presence of long-styled (thrum). and short-styled (pin) individuals within a population, has been repeatedly used as a model for the study of the evolution of the reproductive systems in plants. Erythroxylum havanense is a distylous species in which most thrum plants fail to develop a fertile androecium, thus behaving as Male-sterile or partially Male-sterile plants. Short-styled (thrum) individuals have an increased performance as feMale parents, thereby compensating for their loss of Male fitness. Previous studies of populations within close proximity to each other suggest that E. havanense may be involved in a process of gender specialization in which, unlike other heterostylous species, thrum plants are specializing as feMales and pins (long-styled) as Males. In this paper we describe more general patterns of Male Sterility, one of the first steps in the evolution of gender specialization, among populations of the distylous shrub Erythroxylum havanense . Pollen germination differed among populations (range 0.52 ± 0.03 to 0.06 ± 0.04), and between morphs. Pollen from pin plants was almost two times (1.89) as fertile as that from thrums (0.36 ± 0.03 and 0.19 ± 0.03, pin and thrums respectively). Thrums were significantly more Male sterile in four out of five populations. The population where differences between the floral morphs were not apparent showed the lowest levels of pollen fertility. Accordingly, our results indicate that populations of E. havanense show marked differences in pollen fertility and higher Male Sterility associated with the thrum morph. We hypothesize that differences between morphs could be explained if restorers of Male Sterility are linked to the distyly haplotype, while differences in genes associated with Male Sterility could explain the variation among populations. Overall, the prevalence of thrum-biased Male Sterility across populations suggests that E. havanense is subject to a process of gender specialization.
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morph biased Male Sterility in the tropical distylous shrub erythroxylum havanense erythroxylaceae
American Journal of Botany, 1997Co-Authors: Cesar A Dominguez, German Avilasakar, Sonia Vazquezsantana, Judith MarquezguzmanAbstract:This study explores whether ecological factors, such as pollinators and pollen flow, or variation in pollen and ovule development account for the observed differences (approximately twofold) in the reproductive output of pin and thrum individuals of Erythroxylum havanense. The importance of ecological factors was assessed by means of comparison of the identity of pollinators and the rates of flower visitation, and by performing controlled hand pollinations and measurements of fruit set. In addition, we described the pollen and ovule development of thrum and pin individuals. Our results indicate that pollinators of E. havanense do not distinguish between floral morphs. The differences in fruit set between pin and thrum plants held even after hand pollination and, therefore, the observed differences in reproductive output between floral morphs of E. havanense cannot be explained in terms of asymmetrical pollen flow. There were no differences in the pattern of gynoecium development between the pin and thrum morphs, however androecium development showed marked differences between the morphs, and there was a resemblance between the developmental pathways leading to Male Sterility of the thrum morph of E. havanense with that of species with cytoplasmic Male Sterility (CMS).
Judith Marquezguzman - One of the best experts on this subject based on the ideXlab platform.
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morph biased Male Sterility in the tropical distylous shrub erythroxylum havanense erythroxylaceae
American Journal of Botany, 1997Co-Authors: Cesar A Dominguez, German Avilasakar, Sonia Vazquezsantana, Judith MarquezguzmanAbstract:This study explores whether ecological factors, such as pollinators and pollen flow, or variation in pollen and ovule development account for the observed differences (approximately twofold) in the reproductive output of pin and thrum individuals of Erythroxylum havanense. The importance of ecological factors was assessed by means of comparison of the identity of pollinators and the rates of flower visitation, and by performing controlled hand pollinations and measurements of fruit set. In addition, we described the pollen and ovule development of thrum and pin individuals. Our results indicate that pollinators of E. havanense do not distinguish between floral morphs. The differences in fruit set between pin and thrum plants held even after hand pollination and, therefore, the observed differences in reproductive output between floral morphs of E. havanense cannot be explained in terms of asymmetrical pollen flow. There were no differences in the pattern of gynoecium development between the pin and thrum morphs, however androecium development showed marked differences between the morphs, and there was a resemblance between the developmental pathways leading to Male Sterility of the thrum morph of E. havanense with that of species with cytoplasmic Male Sterility (CMS).
K. B. Saxena - One of the best experts on this subject based on the ideXlab platform.
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development of cytoplasmic nuclear Male Sterility its inheritance and potential use in hybrid pigeonpea breeding
Journal of Heredity, 2010Co-Authors: K. B. Saxena, V K Ravikoti, Vijay A Dalvi, L B Pandey, Guruprasad GaddikeriAbstract:Pigeonpea [Cajanus cajan (L.) Millsp.] is a unique food legume because of its partial (20-30%) outcrossing nature, which provides an opportunity to breed commercial hybrids. To achieve this, it is essential to have a stable Male-Sterility system. This paper reports the selection of a cytoplasmic-nuclear Male-Sterility (CMS) system derived from an interspecific cross between a wild relative of pigeonpea (Cajanus sericeus Benth. ex. Bak.) and a cultivar. This Male-Sterility source was used to breed agronomically superior CMS lines in early (ICPA 2068), medium (ICPA 2032), and late (ICPA 2030) maturity durations. Twenty-three fertility restorers and 30 Male-Sterility maintainers were selected to develop genetically diverse hybrid combinations. Histological studies revealed that vacuolation of growing tetrads and persistence of tetrad wall were primary causes of the manifestation of Male Sterility. Genetic studies showed that 2 dominant genes, of which one had inhibitory gene action, controlled fertility restoration in the hybrids. The experimental hybrids such as TK 030003 and TK 030009 in early, ICPH 2307 and TK 030625 in medium, and TK 030861 and TK 030851 in late maturity groups exhibited 30-88% standard heterosis in multilocation trials.
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Male Sterility systems in pigeonpea and their role in enhancing yield
Plant Breeding, 2010Co-Authors: K. B. Saxena, Nalini Mallikarjuna, S L Sawargaonkar, Rachit K Saxena, R Sultana, R. V. Kumar, Rajeev K VarshneyAbstract:Male-Sterility has been successfully used for enhancing yield in a number of cereal and vegetable crops. In food legumes, this technology could never be used either due to non-availability of natural out-crossing system, or an efficient Male-Sterility system or both. Pigeonpea [Cajanus cajan (L.) Millsp.] is a partially cross-pollinated food legume and recent success in breeding a stable Male-Sterility system has allowed breeders to exploit hybrid vigour for increasing yields. The cytoplasmic-nuclear Male-Sterility (CMS)-based hybrids have recorded 28.4% yield superiority over local checks in farmers' fields. This paper besides summarizing the reports of all the genetic and CMS systems, also discusses the prospects of utilizing these Male-Sterility systems in commercial hybrid breeding programmes.
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hybrid pigeonpea pushkal world s first cytoplasmic Male Sterility based legume
2008Co-Authors: K. B. SaxenaAbstract:The world’s first pigeonpea hybrid, ICPH 8, based on the genetic-Male Sterility (GMS) system, was released in 1991 by ICRISAT and ICAR. This is considered a milestone in the history of food legume breeding. Subsequently, five other GMS-based hybrids were released by various ICAR institutions. In spite of demonstrating high yields, these hybrids could not reach farmers’ fields because of their high costs and quality concerns. The inherent constraints were associated with the seed multiplication of their feMale parents, and this was a major bottleneck in large scale hybrid seed production.
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a new cytoplasmic nuclear Male Sterility system derived from cultivated pigeonpea cytoplasm
Euphytica, 2005Co-Authors: Nalini Mallikarjuna, K. B. SaxenaAbstract:Cytoplasmic Male-Sterility (CMS) in pigeonpea has been reported when some wild relatives of pigeonpea were crossed as the feMale parent with cultivated types as the Male parent. In this paper we report a new source of CMS developed by using the cultivated pigeonpea as the feMale parent and one of its wild relative Cajanus acutifolius as the pollen donor. This is the first report in pigeonpea where CMS has been developed using the cytoplasm of cultivated pigeonpea. Several pure line cultivars of pigeonpea restored pollen fertility whereas cv. HPL 24 partially maintained Male-Sterility. The wild species C. acutifolius used as one of the parents, maintained complete Sterility. Cytological analysis revealed that both in Male-sterile as well as the fertile floral buds, meiosis proceeded normally till the tetrad stage. However in the Male-sterile genotypes during the formation of tetrads, the pollen mother cell (PMC) wall did not dissolve to release the tetrads unlike in the fertile genotypes and this major event was found to be responsible for Male-Sterility.
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development of a cytoplasmic nuclear Male Sterility system in pigeonpea using c scarabaeoides l thouars
Indian Journal of Genetics and Plant Breeding, 2003Co-Authors: K. B. Saxena, R. V. KumarAbstract:The phenomenon of heterosis has been successfully exploited for the genetic enhancement of yield in a number of cereal and horticultural crops. In pigeonpea (Cajanus cajan (L.) Millsp.) also, significant yield gains have been demonstrated through genetic Male-Sterility based hybrid technology. These hybrids, however, could not create the expected impact due to difficulties encountered in their large-scale seed production. To overcome this bottleneck, a cytoplasmic-nuclear Male-Sterility system was developed from a cross between Cajanus scarabaeoides (L.) Thouars, a wild relative of pigeonpea, and a short-duration pigeonpea cultivar. This paper besides summarizing the results of F1 and backcross generations, reports the maintenance and fertility restoration systems of this newly developed cytoplasmic nuclear Male-Sterility source. The development of this technology is expected to help the seed industry in large-scale seed production of pigeonpea hybrids and their parents.
Deng, Xing Wang - One of the best experts on this subject based on the ideXlab platform.
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Construction of a Male Sterility system for hybrid rice breeding and seed production using a nuclear Male Sterility gene
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2016Co-Authors: Chang Zhenyi, Na Wang, Chen Zhufeng, Xie Gang, Lu Jiawei, Yan Wei, Zhou Junli, Tang Xiaoyan, Deng, Xing WangAbstract: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 alpha-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 similar to 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.Guangdong Innovative Research Team Program [201001S0104725509]; Ministry of Agriculture Transgenic Program [2012ZX08001001]; Shenzhen Commission on Innovation and Technology Programs [JCYJ20130402154520292, KQF201109160004A, JSGG20150508105340526]SCI(E)ARTICLEtxy@frontier-ag.com; deng@pku.edu.cn4914145-1415011
Letian Chen - One of the best experts on this subject based on the ideXlab platform.
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Male Sterility and fertility restoration in crops
Annual Review of Plant Biology, 2014Co-Authors: Letian ChenAbstract:In plants, Male Sterility can be caused either by mitochondrial genes with coupled nuclear genes or by nuclear genes alone; the resulting conditions are known as cytoplasmic Male Sterility (CMS) and genic Male Sterility (GMS), respectively. CMS and GMS facilitate hybrid seed production for many crops and thus allow breeders to harness yield gains associated with hybrid vigor (heterosis). In CMS, layers of interaction between mitochondrial and nuclear genes control its Male specificity, occurrence, and restoration of fertility. Environment-sensitive GMS (EGMS) mutants may involve epigenetic control by noncoding RNAs and can revert to fertility under different growth conditions, making them useful breeding materials in the hybrid seed industry. Here, we review recent research on CMS and EGMS systems in crops, summarize general models of Male Sterility and fertility restoration, and discuss the evolutionary significance of these reproductive systems.
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a detrimental mitochondrial nuclear interaction causes cytoplasmic Male Sterility in rice
Nature Genetics, 2013Co-Authors: Ce Fang, Chonghui Ji, Qunyu Zhang, Letian Chen, Heying Li, Hong Xu, Hao Wu, Hong Wu, Huiqi ZhengAbstract:Yao-Guang Liu and colleagues identify the molecular basis of Male Sterility in the Wild Abortive CMS (CMS-WA) system that has been widely used for hybrid rice breeding. They report that a new mitochondrial gene, WA532, confers Male Sterility because its protein product interacts with the mitochondrial protein COX11 and leads to cytoplasmic-nuclear incompatibility.