Brachytic stem is a major trait in plant type .of soybean and its yield potential may be higher under high population when compared with normal stem. In the present investigation, 152 recombinant inbred line （RIL） f...Brachytic stem is a major trait in plant type .of soybean and its yield potential may be higher under high population when compared with normal stem. In the present investigation, 152 recombinant inbred line （RIL） families derived from the cross of Bogao （normal stem） and Nannong 94-156 （brachytic stem） were used to map genes and QTLs of three plant type traits and to identify the effects of brachytic stem on agronomic traits such as yield. The primary results indicated that brachytic stem （sb） and determinate growth habit （drl） were mapped on linkage groups B2 and L, three major QTLs related to plant height were detected and mapped on linkage group L near drl, another minor QTL was mapped near sb on linkage group B2-1. Lines with brachytic stem had shorter plant height, lower biomass, yield, harvest index and pods per plant, and essentially no differences in days to maturity and 100-seed weight when compared with normal stem lines. It was obvious that the effect of brachytic stem on yield was due to the decreased height, biomass and harvest index.展开更多
[Objectives] To study the underground stem tissue structure and agronomic traits of different populations of wild Houttuynia cordata Thumb. [Methods] 8 different populations of wild Houttuynia cordata Thumb. in southe...[Objectives] To study the underground stem tissue structure and agronomic traits of different populations of wild Houttuynia cordata Thumb. [Methods] 8 different populations of wild Houttuynia cordata Thumb. in southern China were selected,the preliminary study was carried out about underground stem tissue structure( stem wall thickness,underground stem cross section diameter,medullary cavity,large vascular bundle area,small vascular bundle area,and number of vascular bundles),and main agronomic traits of aboveground and underground parts. [Results]There were significant differences in the underground stem tissue structure and agronomic traits of some populations of wild Houttuynia cordata Thumb. [Conclusions] From comparison,it reached the conclusion that the populations of wild Houttuynia cordata Thumb. in Kunming of Yunnan,Hechuan of Chongqing,and Nanning of Guangxi showed better underground stem tissue structure and agronomic traits. The results are expected to provide certain guidance for cultivation,reasonable development,and utilization of wild populations of Houttuynia cordata Thumb.展开更多
Understanding functional relations among plant traits and their modulation by growing conditions is imperative in designing selection strategies for breeding programs. This study assessed trait relationships among 196...Understanding functional relations among plant traits and their modulation by growing conditions is imperative in designing selection strategies for breeding programs. This study assessed trait relationships among 196 common bean genotypes exposed to stresses for drought and field infestation of bean fly or bean stem maggot(BSM). The study was carried out at two locations and data was analyzed with linear correlation, path coefficient and genotype × trait biplot analyses. Multiple trait data related to mechanisms of drought and bean fly tolerance were collected on 196 genotypes grown under i) water deficit at mid-pod fill, or ii) unprotected against bean fly; iii) irrigated, well watered conditions, or iv) bean fly protection with chemicals. Seed yield exhibited positive and significant correlations with leaf chlorophyll content, vertical root pulling resistance, pod harvest index, pods per plant and seeds per pod at both phenotypic and genotypic levels under stress and non-stress conditions. Genotypic correlations of traits with seed yield were greater than their respective phenotypic correlations across environments indicating the greater contribution of genotypic factors to the trait correlation. Pods per plant and seeds per pod had high positive direct effects on seed yield both under stress and non-stress whereas pods per plant had the highest indirect effect on seed yield through pod harvest index under stress.In general, our results suggest that vertical root pulling resistance and pod harvest index are important selection objectives for improving seed yield in common beans under non-stress and stress conditions, and particularly useful for drought and BSM tolerance evaluation.展开更多
In this study,effects of temperature,light and their interactions on allelopathic effects and the functional traits specific leaf area(SLA)and stem mass fraction(SMF)of different allelopathic potential rice accessions...In this study,effects of temperature,light and their interactions on allelopathic effects and the functional traits specific leaf area(SLA)and stem mass fraction(SMF)of different allelopathic potential rice accessions at different growth stages were analyzed.The main results were as follows:Allelopathic responses to temperature and light varied with different allelopathic potential rice accessions at different growth stages.With the rise of temperature and the extension of photoperiod,allelopathic effect increased firstly and then decreased at 2–3 leaf stage,but increased constantly at the 4–5 and 7–8 leaf stages in strong allelopathic rice accessions[O.longistaminata,F1(O.longistaminata×RD23),F2(RL159 and RL169)].Temperature had significant impact on allelopathic effect without considering light factors,but light showed little effect on rice allelopathy at the same temperature conditions.The greatest allelopathic effect was attained with moderate temperature and long photoperiod at 2–3 leaf stage in strong allelopathic rice accessions,but all the rice accessions showed weak allelopathic effects at the low temperature condition(15oC/10oC),and the influence of different factors on allelopathy followed a general trend as temperature>leaf stage>light,indicating that among the multiple factors impacting rice allelopathy,temperature was the main factor.Allelopathic characteristics of F1 and F2 to various temperature and light were similar to O.longistaminata,showing that allelopathic genes from wild rice can be expressed in its descendants.Temperature and light also had significant effects on SLA and SMF,and rice allelopathy was closely correlative to SLA in strong allelopathic rice accessions at the 4–5 and 7–8 leaf stages,but there was no correlation between rice allelopathy and SMF at different growth stages.These results suggested that rice adjust the relationship between allelopathy and SLA and adapt to the varied environments,and that high temperature and long photoperiod can enhance rice allelopathic activity.展开更多
Advanced backcross QTL analysis was used to identify QTLs for seven yield and yield-related traits in a BC2F2 population from the cross between a popular Oryza sativa cv Swarna and O. nivara IRGC81848. Transgressive s...Advanced backcross QTL analysis was used to identify QTLs for seven yield and yield-related traits in a BC2F2 population from the cross between a popular Oryza sativa cv Swarna and O. nivara IRGC81848. Transgressive segregants with more than 15% increased effect over Swarna were observed for all the traits except days to heading and days to 50% flowering. Thirty QTLs were detected for seven yield and yield-related traits using interval and composite interval mapping. Enhancing alleles at 13 (45%) of these QTLs were derived from O. nivara, and enhancing alleles at all the QTLs for stem diameter and rachis diameter were derived from O. nivara. Three stem diameter QTLs, two rachis diameter QTLs and one number of secondary branches QTL identified by both Interval and composite interval mapping contributed more than 15% of the total phenotypic variance. The QTL epistasis was significant for stem diameter and plot yield. The most significant QTLs qSD7.2, qSD8.1 and qSD9.1 for stem diameter, qRD9.1 for rachis diameter and qNSB1.1 for number of secondary branches are good targets to evaluate their use in marker-assisted selection. O. nivara is a good source of novel alleles for yield related traits and reveals major effect QTLs suitable for marker-assisted selection.展开更多
基金This work was supported by the National 973 Program(2004CB7206)National 863 Program of China(2002AA211052)Jiangsu Provincial Natural Science Foundation(BK2004045).
文摘Brachytic stem is a major trait in plant type .of soybean and its yield potential may be higher under high population when compared with normal stem. In the present investigation, 152 recombinant inbred line （RIL） families derived from the cross of Bogao （normal stem） and Nannong 94-156 （brachytic stem） were used to map genes and QTLs of three plant type traits and to identify the effects of brachytic stem on agronomic traits such as yield. The primary results indicated that brachytic stem （sb） and determinate growth habit （drl） were mapped on linkage groups B2 and L, three major QTLs related to plant height were detected and mapped on linkage group L near drl, another minor QTL was mapped near sb on linkage group B2-1. Lines with brachytic stem had shorter plant height, lower biomass, yield, harvest index and pods per plant, and essentially no differences in days to maturity and 100-seed weight when compared with normal stem lines. It was obvious that the effect of brachytic stem on yield was due to the decreased height, biomass and harvest index.
基金Supported by Project of Key Discipline Pratacultural Science of Hunan Province during the Twelfth Five-Year Plan Period(540390211002)
文摘[Objectives] To study the underground stem tissue structure and agronomic traits of different populations of wild Houttuynia cordata Thumb. [Methods] 8 different populations of wild Houttuynia cordata Thumb. in southern China were selected,the preliminary study was carried out about underground stem tissue structure( stem wall thickness,underground stem cross section diameter,medullary cavity,large vascular bundle area,small vascular bundle area,and number of vascular bundles),and main agronomic traits of aboveground and underground parts. [Results]There were significant differences in the underground stem tissue structure and agronomic traits of some populations of wild Houttuynia cordata Thumb. [Conclusions] From comparison,it reached the conclusion that the populations of wild Houttuynia cordata Thumb. in Kunming of Yunnan,Hechuan of Chongqing,and Nanning of Guangxi showed better underground stem tissue structure and agronomic traits. The results are expected to provide certain guidance for cultivation,reasonable development,and utilization of wild populations of Houttuynia cordata Thumb.
基金the Alliance for Green Revolution in Africa (AGRA) PASS project for providing financial support for the field studythe South Agricultural Research Institute (SARI) for hosting this researchDrs. I.M. Rao and B. Raatz at CIAT for supplying methods to analyze the recombinant inbred lines used as well the Bill and Melinda Gates Foundation through the Generation Challenge Program (GCP), Tropical Legume I (TL-I) project, for financial support to the research
文摘Understanding functional relations among plant traits and their modulation by growing conditions is imperative in designing selection strategies for breeding programs. This study assessed trait relationships among 196 common bean genotypes exposed to stresses for drought and field infestation of bean fly or bean stem maggot(BSM). The study was carried out at two locations and data was analyzed with linear correlation, path coefficient and genotype × trait biplot analyses. Multiple trait data related to mechanisms of drought and bean fly tolerance were collected on 196 genotypes grown under i) water deficit at mid-pod fill, or ii) unprotected against bean fly; iii) irrigated, well watered conditions, or iv) bean fly protection with chemicals. Seed yield exhibited positive and significant correlations with leaf chlorophyll content, vertical root pulling resistance, pod harvest index, pods per plant and seeds per pod at both phenotypic and genotypic levels under stress and non-stress conditions. Genotypic correlations of traits with seed yield were greater than their respective phenotypic correlations across environments indicating the greater contribution of genotypic factors to the trait correlation. Pods per plant and seeds per pod had high positive direct effects on seed yield both under stress and non-stress whereas pods per plant had the highest indirect effect on seed yield through pod harvest index under stress.In general, our results suggest that vertical root pulling resistance and pod harvest index are important selection objectives for improving seed yield in common beans under non-stress and stress conditions, and particularly useful for drought and BSM tolerance evaluation.
基金financially supported by the National Natural Science Foundation of China (Grant No. 31260453)the Science and Technology Innovation Talents Project of Yunnan Province, China (Grant No. 2014HB039)
文摘In this study,effects of temperature,light and their interactions on allelopathic effects and the functional traits specific leaf area(SLA)and stem mass fraction(SMF)of different allelopathic potential rice accessions at different growth stages were analyzed.The main results were as follows:Allelopathic responses to temperature and light varied with different allelopathic potential rice accessions at different growth stages.With the rise of temperature and the extension of photoperiod,allelopathic effect increased firstly and then decreased at 2–3 leaf stage,but increased constantly at the 4–5 and 7–8 leaf stages in strong allelopathic rice accessions[O.longistaminata,F1(O.longistaminata×RD23),F2(RL159 and RL169)].Temperature had significant impact on allelopathic effect without considering light factors,but light showed little effect on rice allelopathy at the same temperature conditions.The greatest allelopathic effect was attained with moderate temperature and long photoperiod at 2–3 leaf stage in strong allelopathic rice accessions,but all the rice accessions showed weak allelopathic effects at the low temperature condition(15oC/10oC),and the influence of different factors on allelopathy followed a general trend as temperature>leaf stage>light,indicating that among the multiple factors impacting rice allelopathy,temperature was the main factor.Allelopathic characteristics of F1 and F2 to various temperature and light were similar to O.longistaminata,showing that allelopathic genes from wild rice can be expressed in its descendants.Temperature and light also had significant effects on SLA and SMF,and rice allelopathy was closely correlative to SLA in strong allelopathic rice accessions at the 4–5 and 7–8 leaf stages,but there was no correlation between rice allelopathy and SMF at different growth stages.These results suggested that rice adjust the relationship between allelopathy and SLA and adapt to the varied environments,and that high temperature and long photoperiod can enhance rice allelopathic activity.
基金the Department of Biotechnology, Government of India for financial support to the Network Project on Functional Genomics of rice at the Directorate of Rice Research, Andhra Pradesh, India
文摘Advanced backcross QTL analysis was used to identify QTLs for seven yield and yield-related traits in a BC2F2 population from the cross between a popular Oryza sativa cv Swarna and O. nivara IRGC81848. Transgressive segregants with more than 15% increased effect over Swarna were observed for all the traits except days to heading and days to 50% flowering. Thirty QTLs were detected for seven yield and yield-related traits using interval and composite interval mapping. Enhancing alleles at 13 (45%) of these QTLs were derived from O. nivara, and enhancing alleles at all the QTLs for stem diameter and rachis diameter were derived from O. nivara. Three stem diameter QTLs, two rachis diameter QTLs and one number of secondary branches QTL identified by both Interval and composite interval mapping contributed more than 15% of the total phenotypic variance. The QTL epistasis was significant for stem diameter and plot yield. The most significant QTLs qSD7.2, qSD8.1 and qSD9.1 for stem diameter, qRD9.1 for rachis diameter and qNSB1.1 for number of secondary branches are good targets to evaluate their use in marker-assisted selection. O. nivara is a good source of novel alleles for yield related traits and reveals major effect QTLs suitable for marker-assisted selection.
