The Experts below are selected from a list of 228 Experts worldwide ranked by ideXlab platform
Kazuhiro Ohba - One of the best experts on this subject based on the ideXlab platform.
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impact of humidity on temperature induced grain Sterility in rice oryza sativa l
Journal of Agronomy and Crop Science, 2008Co-Authors: W M W Weerakoon, A. Maruyama, Kazuhiro OhbaAbstract:High temperature-induced grain Sterility in rice is becoming a serious problem in tropical rice-growing ecosystems. We studied the mechanism of high temperature-induced grain Sterility of different rice (Oryza sativa L) cultivars at two relative humidity (RH) levels. Four varieties of Indica and Japonica rice were exposed to over 85 % RH and 60 % RH at 36/30 °C, 34/30 °C, 32/24 °C and 30/24 °C day/night air temperatures from late booting to maturity inside sunlit phytotrons. Increasing both air temperature and RH significantly increased spikelet Sterility while high temperature-induced Sterility decreased significantly with decreasing RH. Neither Indica nor Japonica rice types were superior to the other in the response of their spikelets to increased air temperature and RH. Increased spikelet Sterility was due to increased pollen grain Sterility which reduced deposition of viable pollen grains on stigma. Reduction in Sterility with decreased RH was more due to decreased spikelet temperature than to air temperature. Thus the impact of RH should be considered when interpreting the effect of high temperature on grain Sterility. Spikelet fertility was curvilinearly related to spikelet temperature. Grain Sterility increased when spikelet temperature increased over 30 °C while it became completely sterile at 36 °C. The ability of a variety to decrease its spikelet temperature with decreasing RH could be considered as avoidance while the variability in spikelet Sterility among varieties at a given spikelet temperature could be considered as true tolerance.
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Impact of humidity on temperature-induced grain Sterility in rice (Oryza sativa L)
Journal of Agronomy and Crop Science, 2008Co-Authors: W M W Weerakoon, A. Maruyama, Kazuhiro OhbaAbstract:High temperature-induced grain Sterility in rice is becoming a serious problem in tropical rice-growing ecosystems. We studied the mechanism of high temperature-induced grain Sterility of different rice (Oryza sativa L) cultivars at two relative humidity (RH) levels. Four varieties of Indica and Japonica rice were exposed to over 85 % RH and 60 % RH at 36/30 degrees C, 34/30 degrees C, 32/24 degrees C and 30/24 degrees C day/night air temperatures from late booting to maturity inside sunlit phytotrons. Increasing both air temperature and RH significantly increased spikelet Sterility while high temperature-induced Sterility decreased significantly with decreasing RH. Neither Indica nor Japonica rice types were superior to the other in the response of their spikelets to increased air temperature and RH. Increased spikelet Sterility was due to increased pollen grain Sterility which reduced deposition of viable pollen grains on stigma. Reduction in Sterility with decreased RH was more due to decreased spikelet temperature than to air temperature. Thus the impact of RH should be considered when interpreting the effect of high temperature on grain Sterility. Spikelet fertility was curvilinearly related to spikelet temperature. Grain Sterility increased when spikelet temperature increased over 30 degrees C while it became completely sterile at 36 degrees C. The ability of a variety to decrease its spikelet temperature with decreasing RH could be considered as avoidance while the variability in spikelet Sterility among varieties at a given spikelet temperature could be considered as true tolerance.
W M W Weerakoon - One of the best experts on this subject based on the ideXlab platform.
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impact of humidity on temperature induced grain Sterility in rice oryza sativa l
Journal of Agronomy and Crop Science, 2008Co-Authors: W M W Weerakoon, A. Maruyama, Kazuhiro OhbaAbstract:High temperature-induced grain Sterility in rice is becoming a serious problem in tropical rice-growing ecosystems. We studied the mechanism of high temperature-induced grain Sterility of different rice (Oryza sativa L) cultivars at two relative humidity (RH) levels. Four varieties of Indica and Japonica rice were exposed to over 85 % RH and 60 % RH at 36/30 °C, 34/30 °C, 32/24 °C and 30/24 °C day/night air temperatures from late booting to maturity inside sunlit phytotrons. Increasing both air temperature and RH significantly increased spikelet Sterility while high temperature-induced Sterility decreased significantly with decreasing RH. Neither Indica nor Japonica rice types were superior to the other in the response of their spikelets to increased air temperature and RH. Increased spikelet Sterility was due to increased pollen grain Sterility which reduced deposition of viable pollen grains on stigma. Reduction in Sterility with decreased RH was more due to decreased spikelet temperature than to air temperature. Thus the impact of RH should be considered when interpreting the effect of high temperature on grain Sterility. Spikelet fertility was curvilinearly related to spikelet temperature. Grain Sterility increased when spikelet temperature increased over 30 °C while it became completely sterile at 36 °C. The ability of a variety to decrease its spikelet temperature with decreasing RH could be considered as avoidance while the variability in spikelet Sterility among varieties at a given spikelet temperature could be considered as true tolerance.
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Impact of humidity on temperature-induced grain Sterility in rice (Oryza sativa L)
Journal of Agronomy and Crop Science, 2008Co-Authors: W M W Weerakoon, A. Maruyama, Kazuhiro OhbaAbstract:High temperature-induced grain Sterility in rice is becoming a serious problem in tropical rice-growing ecosystems. We studied the mechanism of high temperature-induced grain Sterility of different rice (Oryza sativa L) cultivars at two relative humidity (RH) levels. Four varieties of Indica and Japonica rice were exposed to over 85 % RH and 60 % RH at 36/30 degrees C, 34/30 degrees C, 32/24 degrees C and 30/24 degrees C day/night air temperatures from late booting to maturity inside sunlit phytotrons. Increasing both air temperature and RH significantly increased spikelet Sterility while high temperature-induced Sterility decreased significantly with decreasing RH. Neither Indica nor Japonica rice types were superior to the other in the response of their spikelets to increased air temperature and RH. Increased spikelet Sterility was due to increased pollen grain Sterility which reduced deposition of viable pollen grains on stigma. Reduction in Sterility with decreased RH was more due to decreased spikelet temperature than to air temperature. Thus the impact of RH should be considered when interpreting the effect of high temperature on grain Sterility. Spikelet fertility was curvilinearly related to spikelet temperature. Grain Sterility increased when spikelet temperature increased over 30 degrees C while it became completely sterile at 36 degrees C. The ability of a variety to decrease its spikelet temperature with decreasing RH could be considered as avoidance while the variability in spikelet Sterility among varieties at a given spikelet temperature could be considered as true tolerance.
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: Hao Wu, Qunyu Zhang, Letian Chen, Hong Xu, Heying Li, Ce Fang, Hong Wu, Chonghui Ji, 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.
A. Maruyama - One of the best experts on this subject based on the ideXlab platform.
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impact of humidity on temperature induced grain Sterility in rice oryza sativa l
Journal of Agronomy and Crop Science, 2008Co-Authors: W M W Weerakoon, A. Maruyama, Kazuhiro OhbaAbstract:High temperature-induced grain Sterility in rice is becoming a serious problem in tropical rice-growing ecosystems. We studied the mechanism of high temperature-induced grain Sterility of different rice (Oryza sativa L) cultivars at two relative humidity (RH) levels. Four varieties of Indica and Japonica rice were exposed to over 85 % RH and 60 % RH at 36/30 °C, 34/30 °C, 32/24 °C and 30/24 °C day/night air temperatures from late booting to maturity inside sunlit phytotrons. Increasing both air temperature and RH significantly increased spikelet Sterility while high temperature-induced Sterility decreased significantly with decreasing RH. Neither Indica nor Japonica rice types were superior to the other in the response of their spikelets to increased air temperature and RH. Increased spikelet Sterility was due to increased pollen grain Sterility which reduced deposition of viable pollen grains on stigma. Reduction in Sterility with decreased RH was more due to decreased spikelet temperature than to air temperature. Thus the impact of RH should be considered when interpreting the effect of high temperature on grain Sterility. Spikelet fertility was curvilinearly related to spikelet temperature. Grain Sterility increased when spikelet temperature increased over 30 °C while it became completely sterile at 36 °C. The ability of a variety to decrease its spikelet temperature with decreasing RH could be considered as avoidance while the variability in spikelet Sterility among varieties at a given spikelet temperature could be considered as true tolerance.
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Impact of humidity on temperature-induced grain Sterility in rice (Oryza sativa L)
Journal of Agronomy and Crop Science, 2008Co-Authors: W M W Weerakoon, A. Maruyama, Kazuhiro OhbaAbstract:High temperature-induced grain Sterility in rice is becoming a serious problem in tropical rice-growing ecosystems. We studied the mechanism of high temperature-induced grain Sterility of different rice (Oryza sativa L) cultivars at two relative humidity (RH) levels. Four varieties of Indica and Japonica rice were exposed to over 85 % RH and 60 % RH at 36/30 degrees C, 34/30 degrees C, 32/24 degrees C and 30/24 degrees C day/night air temperatures from late booting to maturity inside sunlit phytotrons. Increasing both air temperature and RH significantly increased spikelet Sterility while high temperature-induced Sterility decreased significantly with decreasing RH. Neither Indica nor Japonica rice types were superior to the other in the response of their spikelets to increased air temperature and RH. Increased spikelet Sterility was due to increased pollen grain Sterility which reduced deposition of viable pollen grains on stigma. Reduction in Sterility with decreased RH was more due to decreased spikelet temperature than to air temperature. Thus the impact of RH should be considered when interpreting the effect of high temperature on grain Sterility. Spikelet fertility was curvilinearly related to spikelet temperature. Grain Sterility increased when spikelet temperature increased over 30 degrees C while it became completely sterile at 36 degrees C. The ability of a variety to decrease its spikelet temperature with decreasing RH could be considered as avoidance while the variability in spikelet Sterility among varieties at a given spikelet temperature could be considered as true tolerance.
Bret A. Payseur - One of the best experts on this subject based on the ideXlab platform.
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genomic networks of hybrid Sterility
PLOS Genetics, 2014Co-Authors: Leslie M Turner, Michael A White, Diethard Tautz, Bret A. PayseurAbstract:Hybrid dysfunction, a common feature of reproductive barriers between species, is often caused by negative epistasis between loci (“Dobzhansky-Muller incompatibilities”). The nature and complexity of hybrid incompatibilities remain poorly understood because identifying interacting loci that affect complex phenotypes is difficult. With subspecies in the early stages of speciation, an array of genetic tools, and detailed knowledge of reproductive biology, house mice (Mus musculus) provide a model system for dissecting hybrid incompatibilities. Male hybrids between M. musculus subspecies often show reduced fertility. Previous studies identified loci and several X chromosome-autosome interactions that contribute to Sterility. To characterize the genetic basis of hybrid Sterility in detail, we used a systems genetics approach, integrating mapping of gene expression traits with Sterility phenotypes and QTL. We measured genome-wide testis expression in 305 male F2s from a cross between wild-derived inbred strains of M. musculus musculus and M. m. domesticus. We identified several thousand cis- and trans-acting QTL contributing to expression variation (eQTL). Many trans eQTL cluster into eleven ‘hotspots,’ seven of which co-localize with QTL for Sterility phenotypes identified in the cross. The number and clustering of trans eQTL—but not cis eQTL—were substantially lower when mapping was restricted to a ‘fertile’ subset of mice, providing evidence that trans eQTL hotspots are related to Sterility. Functional annotation of transcripts with eQTL provides insights into the biological processes disrupted by Sterility loci and guides prioritization of candidate genes. Using a conditional mapping approach, we identified eQTL dependent on interactions between loci, revealing a complex system of epistasis. Our results illuminate established patterns, including the role of the X chromosome in hybrid Sterility. The integrated mapping approach we employed is applicable in a broad range of organisms and we advocate for widespread adoption of a network-centered approach in speciation genetics.
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Genetic dissection of a key reproductive barrier between nascent species of house mice
Genetics, 2011Co-Authors: Michael A White, Tim Wiltshire, Brian Steffy, Bret A. PayseurAbstract:Reproductive isolation between species is often caused by deleterious interactions among loci in hybrids. Finding the genes involved in these incompatibilities provides insight into the mechanisms of speciation. With recently diverged subspecies, house mice provide a powerful system for understanding the genetics of reproductive isolation early in the speciation process. Although previous studies have yielded important clues about the genetics of hybrid male Sterility in house mice, they have been restricted to F(1) Sterility or incompatibilities involving the X chromosome. To provide a more complete characterization of this key reproductive barrier, we conducted an F(2) intercross between wild-derived inbred strains from two subspecies of house mice, Mus musculus musculus and Mus musculus domesticus. We identified a suite of autosomal and X-linked QTL that underlie measures of hybrid male Sterility, including testis weight, sperm density, and sperm morphology. In many cases, the autosomal loci were unique to a specific Sterility trait and exhibited an effect only when homozygous, underscoring the importance of examining reproductive barriers beyond the F(1) generation. We also found novel two-locus incompatibilities between the M. m. musculus X chromosome and M. m. domesticus autosomal alleles. Our results reveal a complex genetic architecture for hybrid male Sterility and suggest a prominent role for reproductive barriers in advanced generations in maintaining subspecies integrity in house mice.
