A population of 180 recombinant inbred lines （RILs） was developed by single seed descended from the cross of high yield Upland cotton （Gossypium hirsutum L.） varieties Zhongmiansuo12 （ZMSI2） and 8891, the two pa...A population of 180 recombinant inbred lines （RILs） was developed by single seed descended from the cross of high yield Upland cotton （Gossypium hirsutum L.） varieties Zhongmiansuo12 （ZMSI2） and 8891, the two parents of Xiangzamian2 （XZM2）. A genetic linkage map consisting of 132 loci and covering 865.20 cM was constructed using the RIL population chiefly with SSR markers. Yield and yield components were investigated for RILs in three environments in China. The purpose of the present research was to analyze the relationship between yield and its components and to map QTL for yield and yield components in cotton. QTL were tagged with data sets from single environment （separate analysis） and a set of data from means of the three environments （joint analysis）. A total of 34 QTL for yield and yield components were independently detected in three environments, whereas fifteen QTL were found in joint analysis. Notably, a stable lint percentage QTL qLP-A10-1 was detected both in joint analysis and in two environments of separate analysis, which might be of special value for marker-assisted selection. The QTL detected in the present study provide new information on improving yield and yield components. Results of path analysis showed that bolls/plant had the largest contribution to lint yield, which is consistent with the mid-parent heterosis value in F1. Accordingly, in cotton breeding, bolls/plant can be considered first and other yield components measured as a whole to implement variety enhancement and hybrid selection of cotton.展开更多
[Objective] The study was to explore the molecular interpretation standards on parentage in the seeds of corn variety. [Method] With 16 hybrids and their parents and 202 inbred elites as materials for screening primer...[Objective] The study was to explore the molecular interpretation standards on parentage in the seeds of corn variety. [Method] With 16 hybrids and their parents and 202 inbred elites as materials for screening primers, the artificial groups of two standard diad and two standard triad were respectively established as the verification materials. Genomic DNA of seedlings was extracted by using CTAB method. 137 pairs of SSR primers were selected for SSR amplification and product detection, which was used for the parentage identification of maize varieties. [ Result] Twenty pairs of corn primers with high polymorphism information content （ PIC value）, clearly amplified bands and good reproducibility were screened from 137 pairs of corn SSR primers tested. The identification results of using SSR molecular were consistent with the actual situation. [ Conclusion] It is feasible to identify the parentage of maize variety using SSR markers.展开更多
Maize （Zea mays L.） is one of the world＇s most important cereals and is a staple food for many people in developing countries. However, in acid soils （pH 〈 5.5）, its productivity is limited by aluminium （AI） t...Maize （Zea mays L.） is one of the world＇s most important cereals and is a staple food for many people in developing countries. However, in acid soils （pH 〈 5.5）, its productivity is limited by aluminium （AI） toxicity, besides other factors. The objectives of this study were to： develop AI tolerant maize inbred lines for a maize breeding program in Kenya, develop single cross hybrids （SCHs） from some of the tolerant inbred lines and determine AI tolerance levels of the SCHs. One hundred and seventy five inbreds and 49 SCHs were developed and screened in nutrient culture containing 0 or 222μM using Relative Net Root Growth （RNRG）, hematoxylin staining （HS） and under AI saturated field conditions （44%-45.6%） at Sega and Chepkoilel. Seedling root growth was inhibited in 95% of the inbreds. F hybrids obtained from inbreds varying in A1 tolerance, exhibited tolerance equal to or greater than that of the more tolerant parent indicating a positive transgressive inheritance to AI toxicity. Fifty eight percent of the F SCHs were heterotic for tolerance to AI toxicity. AI tolerance estimated by RNRG was well correlated to that of HS （r2 = 0.88, P 〈 0.005） but minimally correlated with the field estimates （r2 = 0.24-0.35）, implying that RNRG can predict field selection under AI toxic soils by between 24% and 35%. Plant breeders should therefore employ both approaches in selecting cultivars under AI stress. This study has developed and identified A1 tolerant inbreds and SCHs for use in the acid soils of Kenya and similar regions.展开更多
The annual life cycle of the brown seaweed Undariapinnatifida （Harvey） Suringer comprises a macroscopic diploid sporophyte stage and a microscopic haploid gametophyte stage. In 2011, an unusual zoospore-derived mono...The annual life cycle of the brown seaweed Undariapinnatifida （Harvey） Suringer comprises a macroscopic diploid sporophyte stage and a microscopic haploid gametophyte stage. In 2011, an unusual zoospore-derived monoecious gametophyte isolate （designated as line 10-5-3） of U. pinnatifida was observed. To understand this phenomenon, a comprehensive screening of eighty-two previously identified male gametophyte cultures, isolated from three randomly selected cultivars （lines 10, 7, and 5） was performed. Thirty-six of the isolates developed both antheridia and oogonia on the same filamentous fragment in a standard gametogenesis test （SGT： 18℃, 60 umol photons/（m2.s））. Selfing of the monoecious gametophyte or crossing it with a normal male gametophyte both gave rise to morphologically normal sporophytic offspring. However, crossing resulted in a much higher fertilization rate （89.7%）. The hybrid and selfed sporophytic offspring were grown to maturity in flow tanks at an ambient temperature of 10-18℃ over a period of 69 days. Active zoospores were released from both types of mature sporophylls. The majority of these developed into male gametophytes, while 15%-20% developed into the observed monoecious structures on the same filament. Using PCR amplification it was found that all the monoecious gametophyte isolates and the sporophytic offspring resulting from the selfing and crossing lacked the femalelinked microsatellite sequence （a part of the locus Up-AC-2A8, GenBank accession No. AY738602.1）, indicating their male nature. U.pinnatifida is an invasive species in some regions and the implications of the above findings for this species in nature are briefly discussed.展开更多
[Objective] The primary objective of this study was to estimate combining ability and genetic parameters of 17 new inbred lines.[Method] By using 11 commonly used maize inbred lines from Southwest China as testers and...[Objective] The primary objective of this study was to estimate combining ability and genetic parameters of 17 new inbred lines.[Method] By using 11 commonly used maize inbred lines from Southwest China as testers and incomplete diallel cross design,combining ability and heterosis of 17 new inbred lines bred from the land races in Sichuan Basin and its surrounding areas were analyzed.In addition,the genetic parameters and heterotic groups were also investigated based on combining ability.[Result] P1-1,P1-16 and P1-14 with the better comprehensive characters can be directly used in maize breeding program.The SCA of P1-10×P2-4 was high in most traits.It is more possible to obtain high-yield hybrid combinations by the pattern Sipingtou × Lancaster.GCA variance was bigger than SCA variance in four traits such as rows per ear,grains per row,which were affected by the environments slightly and should be selected at early generations;while SCA variance was bigger than GCA variance in five traits such as 100-grain weight and plant weight,which were significantly influenced by environment and thus should be selected in later generations.[Conclusion] The paper will provide theoretical basis for further improvement of local maize varieties.展开更多
The correlation coefficients and scattering were studied in Ki and new inbred lines for phytic acid （PA） and inorganic phosphorus content （InP） content in seeds of tropical maize （Zea mays L.）. The understanding...The correlation coefficients and scattering were studied in Ki and new inbred lines for phytic acid （PA） and inorganic phosphorus content （InP） content in seeds of tropical maize （Zea mays L.）. The understanding of the variability in PA and InP characters would be useful in a breeding program. A total of 16 Ki and 25 new inbred lines of tropical maize were planted in Completely Randomized Design （CRD） during late rainy season, 2007 to early rainy season, 2009 at Inseechandrastitya Institute for Crops Research and Development, Thailand. The result showed low correlation with no statistical significant between PA and InP contents in corn seeds performed either in different sources of inbred lines or years. For PA content, most of inbred lines were skewed toward high PA （〉 900 mg/100 g） both in Ki and new inbred lines in every year. The lowest PA value found in Ki inbred lines both in two years were Ki10, Ki15, Ki20, and Ki52.30A10-S11-43-1-3 was the lowest PA inbred lines observing in two years in new germplasm.展开更多
Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% （w/v） chitosan solutions at 15 ...Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% （w/v） chitosan solutions at 15 ℃ on the growth and physiological changes were investigated using two maize （Zea rnays L.） inbred lines, HuangC （chilling-tolerant） and Mo17 （chilling-sensitive）. While seed priming with chitosan had no significant effect on germination percentage under low temperature stress, it enhanced germination index, reduced the mean germination time （MGT）, and increased shoot height, root length, and shoot and root dry weights in both maize lines. The decline of malondialdehyde （MDA） content and relative permeability of the plasma membrane and the increase of the concentrations of soluble sugars and proline, peroxidase （POD） activity, and catalase （CAT） activity were detected both in the chilling-sensitive and chilling-tolerant maize seedlings after priming with the three concentrations of chitosan. HuangC was less sensitive to responding to different concentrations of chitosan. Priming with 0.50% chitosan for about 60-64 h seemed to have the best effects. Thus, it suggests that seed priming with chitosan may improve the speed of germination of maize seed and benefit for seedling growth under low temperature stress.展开更多
基金This work was supported by the National Science Foundation for Outstanding Youth Scholars (No. 30025029), Chinese National Programs for High Technology Research and Development (No. 2002AA207006), the Teaching and Research Award Program for Outstanding Young Teachers in Higher Education Institutions, and Program for Changjiang Scholars and Innovative Research Team in University of MOE, China.
文摘A population of 180 recombinant inbred lines （RILs） was developed by single seed descended from the cross of high yield Upland cotton （Gossypium hirsutum L.） varieties Zhongmiansuo12 （ZMSI2） and 8891, the two parents of Xiangzamian2 （XZM2）. A genetic linkage map consisting of 132 loci and covering 865.20 cM was constructed using the RIL population chiefly with SSR markers. Yield and yield components were investigated for RILs in three environments in China. The purpose of the present research was to analyze the relationship between yield and its components and to map QTL for yield and yield components in cotton. QTL were tagged with data sets from single environment （separate analysis） and a set of data from means of the three environments （joint analysis）. A total of 34 QTL for yield and yield components were independently detected in three environments, whereas fifteen QTL were found in joint analysis. Notably, a stable lint percentage QTL qLP-A10-1 was detected both in joint analysis and in two environments of separate analysis, which might be of special value for marker-assisted selection. The QTL detected in the present study provide new information on improving yield and yield components. Results of path analysis showed that bolls/plant had the largest contribution to lint yield, which is consistent with the mid-parent heterosis value in F1. Accordingly, in cotton breeding, bolls/plant can be considered first and other yield components measured as a whole to implement variety enhancement and hybrid selection of cotton.
基金Supported by the National Standard Plan(20051079-T-469)~~
文摘[Objective] The study was to explore the molecular interpretation standards on parentage in the seeds of corn variety. [Method] With 16 hybrids and their parents and 202 inbred elites as materials for screening primers, the artificial groups of two standard diad and two standard triad were respectively established as the verification materials. Genomic DNA of seedlings was extracted by using CTAB method. 137 pairs of SSR primers were selected for SSR amplification and product detection, which was used for the parentage identification of maize varieties. [ Result] Twenty pairs of corn primers with high polymorphism information content （ PIC value）, clearly amplified bands and good reproducibility were screened from 137 pairs of corn SSR primers tested. The identification results of using SSR molecular were consistent with the actual situation. [ Conclusion] It is feasible to identify the parentage of maize variety using SSR markers.
文摘Maize （Zea mays L.） is one of the world＇s most important cereals and is a staple food for many people in developing countries. However, in acid soils （pH 〈 5.5）, its productivity is limited by aluminium （AI） toxicity, besides other factors. The objectives of this study were to： develop AI tolerant maize inbred lines for a maize breeding program in Kenya, develop single cross hybrids （SCHs） from some of the tolerant inbred lines and determine AI tolerance levels of the SCHs. One hundred and seventy five inbreds and 49 SCHs were developed and screened in nutrient culture containing 0 or 222μM using Relative Net Root Growth （RNRG）, hematoxylin staining （HS） and under AI saturated field conditions （44%-45.6%） at Sega and Chepkoilel. Seedling root growth was inhibited in 95% of the inbreds. F hybrids obtained from inbreds varying in A1 tolerance, exhibited tolerance equal to or greater than that of the more tolerant parent indicating a positive transgressive inheritance to AI toxicity. Fifty eight percent of the F SCHs were heterotic for tolerance to AI toxicity. AI tolerance estimated by RNRG was well correlated to that of HS （r2 = 0.88, P 〈 0.005） but minimally correlated with the field estimates （r2 = 0.24-0.35）, implying that RNRG can predict field selection under AI toxic soils by between 24% and 35%. Plant breeders should therefore employ both approaches in selecting cultivars under AI stress. This study has developed and identified A1 tolerant inbreds and SCHs for use in the acid soils of Kenya and similar regions.
基金Supported by the National Natural Science Foundation of China(Nos.41176135,41206142)the Innovation Program of Chinese Academy of Sciences(No.KSCX2-EW-B-3)the Ministry of Agriculture of China(No.200903030)
文摘The annual life cycle of the brown seaweed Undariapinnatifida （Harvey） Suringer comprises a macroscopic diploid sporophyte stage and a microscopic haploid gametophyte stage. In 2011, an unusual zoospore-derived monoecious gametophyte isolate （designated as line 10-5-3） of U. pinnatifida was observed. To understand this phenomenon, a comprehensive screening of eighty-two previously identified male gametophyte cultures, isolated from three randomly selected cultivars （lines 10, 7, and 5） was performed. Thirty-six of the isolates developed both antheridia and oogonia on the same filamentous fragment in a standard gametogenesis test （SGT： 18℃, 60 umol photons/（m2.s））. Selfing of the monoecious gametophyte or crossing it with a normal male gametophyte both gave rise to morphologically normal sporophytic offspring. However, crossing resulted in a much higher fertilization rate （89.7%）. The hybrid and selfed sporophytic offspring were grown to maturity in flow tanks at an ambient temperature of 10-18℃ over a period of 69 days. Active zoospores were released from both types of mature sporophylls. The majority of these developed into male gametophytes, while 15%-20% developed into the observed monoecious structures on the same filament. Using PCR amplification it was found that all the monoecious gametophyte isolates and the sporophytic offspring resulting from the selfing and crossing lacked the femalelinked microsatellite sequence （a part of the locus Up-AC-2A8, GenBank accession No. AY738602.1）, indicating their male nature. U.pinnatifida is an invasive species in some regions and the implications of the above findings for this species in nature are briefly discussed.
基金Supported by National Key Technology Research and DevelopmentProgram(2004BA525B04)Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education ofChina(IRT0453)Program for Maize breeding Key Technology ofSichuan Province during 11th Five-Year Plan Period
文摘[Objective] The primary objective of this study was to estimate combining ability and genetic parameters of 17 new inbred lines.[Method] By using 11 commonly used maize inbred lines from Southwest China as testers and incomplete diallel cross design,combining ability and heterosis of 17 new inbred lines bred from the land races in Sichuan Basin and its surrounding areas were analyzed.In addition,the genetic parameters and heterotic groups were also investigated based on combining ability.[Result] P1-1,P1-16 and P1-14 with the better comprehensive characters can be directly used in maize breeding program.The SCA of P1-10×P2-4 was high in most traits.It is more possible to obtain high-yield hybrid combinations by the pattern Sipingtou × Lancaster.GCA variance was bigger than SCA variance in four traits such as rows per ear,grains per row,which were affected by the environments slightly and should be selected at early generations;while SCA variance was bigger than GCA variance in five traits such as 100-grain weight and plant weight,which were significantly influenced by environment and thus should be selected in later generations.[Conclusion] The paper will provide theoretical basis for further improvement of local maize varieties.
文摘The correlation coefficients and scattering were studied in Ki and new inbred lines for phytic acid （PA） and inorganic phosphorus content （InP） content in seeds of tropical maize （Zea mays L.）. The understanding of the variability in PA and InP characters would be useful in a breeding program. A total of 16 Ki and 25 new inbred lines of tropical maize were planted in Completely Randomized Design （CRD） during late rainy season, 2007 to early rainy season, 2009 at Inseechandrastitya Institute for Crops Research and Development, Thailand. The result showed low correlation with no statistical significant between PA and InP contents in corn seeds performed either in different sources of inbred lines or years. For PA content, most of inbred lines were skewed toward high PA （〉 900 mg/100 g） both in Ki and new inbred lines in every year. The lowest PA value found in Ki inbred lines both in two years were Ki10, Ki15, Ki20, and Ki52.30A10-S11-43-1-3 was the lowest PA inbred lines observing in two years in new germplasm.
基金Project supported by the Major Science and Technology Special Project (priority subject) of Zhejiang Province (No. 2008C12005-1)the Key Project of Education Department of Zhejiang Province (No. 20070147), China
文摘Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% （w/v） chitosan solutions at 15 ℃ on the growth and physiological changes were investigated using two maize （Zea rnays L.） inbred lines, HuangC （chilling-tolerant） and Mo17 （chilling-sensitive）. While seed priming with chitosan had no significant effect on germination percentage under low temperature stress, it enhanced germination index, reduced the mean germination time （MGT）, and increased shoot height, root length, and shoot and root dry weights in both maize lines. The decline of malondialdehyde （MDA） content and relative permeability of the plasma membrane and the increase of the concentrations of soluble sugars and proline, peroxidase （POD） activity, and catalase （CAT） activity were detected both in the chilling-sensitive and chilling-tolerant maize seedlings after priming with the three concentrations of chitosan. HuangC was less sensitive to responding to different concentrations of chitosan. Priming with 0.50% chitosan for about 60-64 h seemed to have the best effects. Thus, it suggests that seed priming with chitosan may improve the speed of germination of maize seed and benefit for seedling growth under low temperature stress.
