Five F2 segregation populations, derived from crosses between the susceptible japonica cultivars （cvs.） Kongyul31 and donor cvs. Aichi Asahi （AA）, BL1, Digu, Pai-kan-tao （PKT） and Oryzica Llanos 5 （ORL5）, were...Five F2 segregation populations, derived from crosses between the susceptible japonica cultivars （cvs.） Kongyul31 and donor cvs. Aichi Asahi （AA）, BL1, Digu, Pai-kan-tao （PKT） and Oryzica Llanos 5 （ORL5）, were used to evaluate their natural resistance to blast in cold region. The field test of their blast resistance was conducted in 858 Farm, which showed that Aichi Asahi, BL 1 and Digu were highly resistant to either leaf blast or neck blast and could be used to develop molecular breeding by design, and genetic analysis indicated that the field resistance of Aichi Asahi, BLland Digu to leaf blast and neck blast was controlled by a single dominant gene, and the leaf blast and neck blast resistance in the donor cv. Pai-kan-tao was inherited as a single recessive gene, the neck blast resistance of the donor cv. Oryzica Llanos 5 was controlled by a single recessive gene while its leaf blast resistance was not controlled by this gene. These results suggested that five parental varieties positively contributed to resistance to either leaf blast or neck blast and could be used to expand the genetic germplasms resistant to blast in cold region using molecular assisted selection.展开更多
Non-Mendelian segregation of markers,known as distorted segregation,is a common biological phenomenon.Although segregation distortion affects the estimation of map distances and the results of quantitative trait loci(...Non-Mendelian segregation of markers,known as distorted segregation,is a common biological phenomenon.Although segregation distortion affects the estimation of map distances and the results of quantitative trait loci(QTL)mapping,the effects of distorted markers are often ignored in the construction of linkage maps and in QTL mapping.Recently,we have developed a multipoint method via a Hidden Markov chain method to reconstruct linkage maps in an F2 population that corrects for bias of map distances between distorted markers.In this article,the method is extended to cover backcross,doubled haploid and recombinant inbred line(RIL)populations.The results from simulated experiments show that:(1)the degree that two linked segregation distortion loci(SDL)affect the estimation of map distances increases as SDL heritability and interval length between adjacent markers increase,whereas sample size has little effect on the bias;(2)two linked SDL result in the underesti-mation of linkage distances for most cases,overestimation for an additive model with opposite additive effects,and unbiased estimation for an epistatic model with negative additive-by-additive effects;(3)the proposed method can obtain the unbiased estimation of linkage distance.This new method was applied to a rice RIL population with severely distorted segregation to reconstruct the linkage maps,and a bootstrap method was used to obtain 95%confidence intervals of map distances.The results from real data analysis further demonstrate the utility of our method,which provides a foundation for the inheritance analysis of quantitative and viability traits.展开更多
Perpetual blooming is one of the most important biological and economical traits in modern rose, while the genetic basis underlining the control of this trait is poorly investigated. With an aim in dissecting the gene...Perpetual blooming is one of the most important biological and economical traits in modern rose, while the genetic basis underlining the control of this trait is poorly investigated. With an aim in dissecting the genetic determinism of perpetual blooming, we developed six rose populations(OB, W, F1, F2, BC1 OB and BC1W) derived from a WOB population [interspecific diploid hybridization between Rosa chinensis ‘Old Blush'(OB) and R. wichuriana ‘Basye's Thornless'(W)]. Perpetual blooming is absent both in a F1 population with 296 individuals and a BC1 W population(W as the backcross parent) with 150 individuals. However, the perpetual blooming trait showed a typical 3︰1 segregation in a backcross population BC1 OB with OB as the backcross parent. In this population with 300 individuals, 83 plants had the perpetual blooming phenotype while the other 217 featured non-perpetual blooming, indicating that the perpetual blooming trait is very likely controlled by two recessive genes in R. chinensis(rpb1 and rpb2). These genetic data suggest that the inheritance of rose perpetual blooming may be controlled by a complex mechanism.展开更多
基金Supported by the National Science and Technology Support Plan Project (2011BAD16B11)Heilongjiang Key Technologies R&D Program (GA09B106-2)Ph. D Programs Foundation of Northeast Agricultural University (2009RC09)
文摘Five F2 segregation populations, derived from crosses between the susceptible japonica cultivars （cvs.） Kongyul31 and donor cvs. Aichi Asahi （AA）, BL1, Digu, Pai-kan-tao （PKT） and Oryzica Llanos 5 （ORL5）, were used to evaluate their natural resistance to blast in cold region. The field test of their blast resistance was conducted in 858 Farm, which showed that Aichi Asahi, BL 1 and Digu were highly resistant to either leaf blast or neck blast and could be used to develop molecular breeding by design, and genetic analysis indicated that the field resistance of Aichi Asahi, BLland Digu to leaf blast and neck blast was controlled by a single dominant gene, and the leaf blast and neck blast resistance in the donor cv. Pai-kan-tao was inherited as a single recessive gene, the neck blast resistance of the donor cv. Oryzica Llanos 5 was controlled by a single recessive gene while its leaf blast resistance was not controlled by this gene. These results suggested that five parental varieties positively contributed to resistance to either leaf blast or neck blast and could be used to expand the genetic germplasms resistant to blast in cold region using molecular assisted selection.
基金Supported by the 973 program(Grant No.2006CB101708)the National Natural Science Foundation of China(Grant Nos.30470998 and 30671333)+5 种基金Jiangsu Natural Science Foundation(Grant No.BK2005087)Program for Changjiang Scholars and Innovative Research Team in University and Program for New Centenary Excellent Talent in University(Grant No.NCET-05-0489)863 Program(Grant No.2006AA10Z1E5)the Scientific Research Foundation for the Returned Overseas Chinese ScholarsState Education and Personnel Ministrythe Talent Foundation of Nanjing Agricultural University.
文摘Non-Mendelian segregation of markers,known as distorted segregation,is a common biological phenomenon.Although segregation distortion affects the estimation of map distances and the results of quantitative trait loci(QTL)mapping,the effects of distorted markers are often ignored in the construction of linkage maps and in QTL mapping.Recently,we have developed a multipoint method via a Hidden Markov chain method to reconstruct linkage maps in an F2 population that corrects for bias of map distances between distorted markers.In this article,the method is extended to cover backcross,doubled haploid and recombinant inbred line(RIL)populations.The results from simulated experiments show that:(1)the degree that two linked segregation distortion loci(SDL)affect the estimation of map distances increases as SDL heritability and interval length between adjacent markers increase,whereas sample size has little effect on the bias;(2)two linked SDL result in the underesti-mation of linkage distances for most cases,overestimation for an additive model with opposite additive effects,and unbiased estimation for an epistatic model with negative additive-by-additive effects;(3)the proposed method can obtain the unbiased estimation of linkage distance.This new method was applied to a rice RIL population with severely distorted segregation to reconstruct the linkage maps,and a bootstrap method was used to obtain 95%confidence intervals of map distances.The results from real data analysis further demonstrate the utility of our method,which provides a foundation for the inheritance analysis of quantitative and viability traits.
基金funded by a grant from the National Natural Science Foundation of China(31160402)
文摘Perpetual blooming is one of the most important biological and economical traits in modern rose, while the genetic basis underlining the control of this trait is poorly investigated. With an aim in dissecting the genetic determinism of perpetual blooming, we developed six rose populations(OB, W, F1, F2, BC1 OB and BC1W) derived from a WOB population [interspecific diploid hybridization between Rosa chinensis ‘Old Blush'(OB) and R. wichuriana ‘Basye's Thornless'(W)]. Perpetual blooming is absent both in a F1 population with 296 individuals and a BC1 W population(W as the backcross parent) with 150 individuals. However, the perpetual blooming trait showed a typical 3︰1 segregation in a backcross population BC1 OB with OB as the backcross parent. In this population with 300 individuals, 83 plants had the perpetual blooming phenotype while the other 217 featured non-perpetual blooming, indicating that the perpetual blooming trait is very likely controlled by two recessive genes in R. chinensis(rpb1 and rpb2). These genetic data suggest that the inheritance of rose perpetual blooming may be controlled by a complex mechanism.
