To identify genetic loci controlling grain weight, an elite indica rice variety, Baodali, with large grains was identified and used in this study. Its derived F2, F3 and BC2 F2 with another japonica rice variety Zhong...To identify genetic loci controlling grain weight, an elite indica rice variety, Baodali, with large grains was identified and used in this study. Its derived F2, F3 and BC2 F2 with another japonica rice variety Zhonghua 11 were used as mapping populations. Linkage analyses demonstrated that two genes controlling grain weight, designated as GW3 and GW6, were mapped to chromosome 3 and chromosome 6, respectively. Fine mapping delimited GW3 to a 122 kb physical distance between two sequence tagged site markers （WGWt6 and WGW19） containing 16 open reading frames annotated by The Institute for Genomic Research （http：//www.tigr.org）. GW6 was further mapped between two simple sequence repeat markers （RM7179 and RM3187）. These results are useful for both marker assisted selection of grain weight, and for further cloning of GW genes, which will contribute to the dissection of the molecular mechanism underlying grain weight in rice.展开更多
Grain weight and grain number are important yield component traits in wheat and identification of underlying genetic loci is helpful for improving yield.Here,we identified eight stable quantitative trait loci(QTL)for ...Grain weight and grain number are important yield component traits in wheat and identification of underlying genetic loci is helpful for improving yield.Here,we identified eight stable quantitative trait loci(QTL)for yield component traits,including five loci for thousand grain weight(TGW)and three for grain number per spike(GNS)in a recombinant inbred line population derived from cross Yangxiaomai/Zhongyou 9507 across four environments.Since grain size is a major determinant of grain weight,we also mapped QTL for grain length(GL)and grain width(GW).QTGW.caas-2D,QTGW.caas-3B,QTGW.caas-5A and QTGW.caas-7A.2 for TGW co-located with those for grain size.QTGW.caas-2D also had a consistent genetic position with QGNS.caas-2D,suggesting that the pleiotropic locus is a modulator of trade-off effect between TGW and GNS.Sequencing and linkage mapping showed that TaGL3-5A and WAPO-A1 were candidate genes of QTGW.caas-5A and QTGW.caas-7A.2,respectively.We developed Kompetitive allele specific PCR(KASP)markers linked with the stable QTL for yield component traits and validated their genetic effects in a diverse panel of wheat cultivars from the Huang-Huai River Valley region.KASP-based genotyping analysis further revealed that the superior alleles of all stable QTL for TGW but not GNS were subject to positive selection,indicating that yield improvement in the region largely depends on increased TGW.Comparative analyses with previous studies showed that most of the QTL could be detected in different genetic backgrounds,and QTGW.caas-7A.1 is likely a new QTL.These findings provide not only valuable genetic information for yield improvement but also useful tools for marker-assisted selection.展开更多
Paw San Hmwe （PSM） rice has been cultivated in many areas of Myanmar for a long time. Strong aroma, good taste and its elongation during cooking are the key characteristics of PSM rice. Thirty-one PSM accessions wer...Paw San Hmwe （PSM） rice has been cultivated in many areas of Myanmar for a long time. Strong aroma, good taste and its elongation during cooking are the key characteristics of PSM rice. Thirty-one PSM accessions were genotypically characterized, and their physical grain and cooking quality traits were studied. We used specific gene markers associated with aroma, apparent amylose content （AAC） and alkali spreading value to determine the alleles carried by different PSM accessions. The results revealed that six PSM accessions （PSM10, PSM12, PSM13, PSM21, PSM22 and PSM30） had a 3-bp insertion in Os2AP gene. Gel consistency （GC） allele was predominant among the PSM accessions for gelatinization temperature （GT）, however, the phenotype observed was between low and intermediate GT because of the combination of the GC allele with the presence of low GT allele at heterozygous state from the other loci of the SSIla gene. Intermediate to high AAC was observed among the PSM accessions corresponding to the haplotype identified for the single nucleotide polymorphism G/T and the （Cm）n repeat in the Wx gene. The characterization and grouping data of PSM accessions posted benefits to Myanmar seed banks, and our results will help in maintaining the integrity of PSM rice variety.展开更多
Breeding program strategies to develop novel short grain white rice varieties such as japonica(short grain)that introgress biotic stress resistance and high grain quality have been developed usingindica rice(Pin Kaset...Breeding program strategies to develop novel short grain white rice varieties such as japonica(short grain)that introgress biotic stress resistance and high grain quality have been developed usingindica rice(Pin Kaset+4 and Riceberry)for applications in japonica rice(Kashihikari)improvement.Fourbreeding lines showing promising agronomic performance with short grain and low amylose content(<20%)were obtained.In addition,sensory testing of these breeding lines showed high scores thatsimilar to Kashihikari.Two promising lines,KP48-1-5and KP48-1-9,which possessed a combination offour genes resistance to different biotic stresses(Bph3+TPS+Xa21+Pi-ta)and four genes for grainquality(G83+SSlla+w+badh2),were deveiaped using marker-assisted selection(MAS)with thepedigree method.The current study clearly illustrated the successful use of MAS in combining resistanceto multiple biotic stresses while maintaining a high yield potential and preferred grain quality.Moreover,the results indicated that this breeding program,which includes crossing temperate japonica with indica,can create novel short grain rice varieties adapted to a trapical environment like the japonica type.展开更多
In order to create novel germplasm resources for breeding heat tolerant variety,we transferred a dominant allele OsHTAS,previously characterized and cloned from a high-temperature tolerant local variety HT54,which was...In order to create novel germplasm resources for breeding heat tolerant variety,we transferred a dominant allele OsHTAS,previously characterized and cloned from a high-temperature tolerant local variety HT54,which was collected from the rice production area of southern China,into a high-temperature sensitive intermediate breeding line HT13 through six rounds of successive backcross by using marker-assisted selection.The molecular analysis showed that the recovery of genetic background of a resultant near isogenic line(NIL),MHT13,was around 99.8%.The OsHTAS gene introduced in the MHT13 expressed normally in the HT13 genetic background,mediating heat tolerance and phenotype similar to those of the donor parent HT54.The major agronomic traits of MHT13 resembled those of the recurrent parent HT13.Moreover,MHT13 had high general combining ability and its rice quality reached the grade 3 standard of edible high-quality rice issued by Ministry of Agriculture of the People’s Republic of China,which greatly improved its application value in rice production.展开更多
Globally among biotic stresses,diseases like blight,rust and blast constitute prime constraints for reducing wheat productivity especially in Bangladesh.For sustainable productivity,the development of disease-resistan...Globally among biotic stresses,diseases like blight,rust and blast constitute prime constraints for reducing wheat productivity especially in Bangladesh.For sustainable productivity,the development of disease-resistant lines and high yielding varieties is vital and necessary.This study was conducted using 122 advanced breeding lines of wheat including 21 varieties developed by Bangladesh Wheat and Maize Research Institute with aims to identify genotypes having high yield potential and resistant to leaf blight,leaf rust and blast diseases.These genotypes were evaluated for resistance against leaf blight and leaf rust at Dinajpur and wheat blast at Jashore under field condition.Out of 122 genotypes tested,20 lines were selected as resistant to leaf blight based on the area under the diseases progress curve under both irrigated timely sown and irrigated late sown conditions.Forty-two genotypes were found completely free from leaf rust infection,59 genotypes were identified as resistant,and 13 genotypes were identified as moderately resistant to leaf rust.Eighteen genotypes were immune against wheat blast,42 genotypes were categorized as resistant,and 26 genotypes were identified as moderately resistant to wheat blast.Molecular data revealed that the 16 genotypes showed a positive 2NS segment among the 18 immune genotypes selected against wheat blast under field conditions.The genotypes BAW 1322,BAW 1295,and BAW 1203 can be used as earlier maturing genotypes and the genotypes BAW 1372,BAW 1373,BAW 1297 and BAW 1364 can be used for lodging tolerant due to short plant height.The genotypes WMRI Gom 1,BAW 1349 and BAW 1350 can be selected for bold grain and the genotypes WMRI Gom 1,BAW 1297,BAW 1377 can be used as high yielder for optimum seeding condition but genotypes BAW 1377 and BAW 1366 can be used for late sown condition.The selected resistant genotypes against specific diseases can be used in the further breeding program to develop wheat varieties having higher disease resistance and yield potential.展开更多
In China,the market share of a rice cultivar is mainly determined by its yield and quality.Yuzhenxiang is a high-quality variety with extra-slender grain shape,good quality and unique aroma.In order to investigate its...In China,the market share of a rice cultivar is mainly determined by its yield and quality.Yuzhenxiang is a high-quality variety with extra-slender grain shape,good quality and unique aroma.In order to investigate its genetic background,12 pairs of functional markers were used to detect the genotype distribution of eight major grain shape genes including GS3,GW5,GS6,GW6a,GL7/GW7,GLW7,GW8,GS9,one amylase gene Wx and one aroma gene BADH2 in Yuzhenxiang by using Nipponbare,9311,Huazhan,Zhonghui 8015 and Zhonghui 9308 as controls.The results indicated that the slender grain type of Yuzhenxiang was probably affected by GS3 and GL7/GW7 with the positive co-regulation of multiple grain shape genes,and its outstanding rice quality may be resulted from the cumulative effects of GLW7,GW8 and Wx genotypes,while its unique aroma may be mainly regulated by BADH2-E7 deletion.展开更多
1000-Grain weight and spikelet number per panicle are two important components for rice grain yield. In our previous study, eight quantitative trait loci （QTLs） conferring spikelet number per panicle and 1000-grain ...1000-Grain weight and spikelet number per panicle are two important components for rice grain yield. In our previous study, eight quantitative trait loci （QTLs） conferring spikelet number per panicle and 1000-grain weight were mapped through sequencing-based genotyping of 150 rice recombinant inbred lines （RILs）. In this study, we validated the effects of four QTLs from Nipponbare using chromosome segment substitution lines （CSSLs）, and pyramided eight grain yield related QTLs. The new lines containing the eight QTLs with positive effects showed increased panicle and spikelet size as compared with the parent variety 93-11. We further proposed a novel pyramid breeding scheme based on marker-assistant and phenotype selection （MAPS）. This scheme allowed pyramiding of as many as 24 QTLs at a single hybridization without massive cross work. This study provided insights into the molecular basis of rice grain yield for direct wealth for high-yielding rice breeding.展开更多
基金Supported by the National Natural Science Foundation of China (30771317)the State Key Basic Research and Development Plan of China(2005CB120807).
文摘To identify genetic loci controlling grain weight, an elite indica rice variety, Baodali, with large grains was identified and used in this study. Its derived F2, F3 and BC2 F2 with another japonica rice variety Zhonghua 11 were used as mapping populations. Linkage analyses demonstrated that two genes controlling grain weight, designated as GW3 and GW6, were mapped to chromosome 3 and chromosome 6, respectively. Fine mapping delimited GW3 to a 122 kb physical distance between two sequence tagged site markers （WGWt6 and WGW19） containing 16 open reading frames annotated by The Institute for Genomic Research （http：//www.tigr.org）. GW6 was further mapped between two simple sequence repeat markers （RM7179 and RM3187）. These results are useful for both marker assisted selection of grain weight, and for further cloning of GW genes, which will contribute to the dissection of the molecular mechanism underlying grain weight in rice.
基金funded by the National Natural Science Foundation of China(91935304 and 32272182)Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences.
文摘Grain weight and grain number are important yield component traits in wheat and identification of underlying genetic loci is helpful for improving yield.Here,we identified eight stable quantitative trait loci(QTL)for yield component traits,including five loci for thousand grain weight(TGW)and three for grain number per spike(GNS)in a recombinant inbred line population derived from cross Yangxiaomai/Zhongyou 9507 across four environments.Since grain size is a major determinant of grain weight,we also mapped QTL for grain length(GL)and grain width(GW).QTGW.caas-2D,QTGW.caas-3B,QTGW.caas-5A and QTGW.caas-7A.2 for TGW co-located with those for grain size.QTGW.caas-2D also had a consistent genetic position with QGNS.caas-2D,suggesting that the pleiotropic locus is a modulator of trade-off effect between TGW and GNS.Sequencing and linkage mapping showed that TaGL3-5A and WAPO-A1 were candidate genes of QTGW.caas-5A and QTGW.caas-7A.2,respectively.We developed Kompetitive allele specific PCR(KASP)markers linked with the stable QTL for yield component traits and validated their genetic effects in a diverse panel of wheat cultivars from the Huang-Huai River Valley region.KASP-based genotyping analysis further revealed that the superior alleles of all stable QTL for TGW but not GNS were subject to positive selection,indicating that yield improvement in the region largely depends on increased TGW.Comparative analyses with previous studies showed that most of the QTL could be detected in different genetic backgrounds,and QTGW.caas-7A.1 is likely a new QTL.These findings provide not only valuable genetic information for yield improvement but also useful tools for marker-assisted selection.
基金supported by the National Center for Genetic Engineering and Biotechnology,Thailand (Grant No.P1020028)Generation Challenge Program,Mexico (Grant No.P0900835)
文摘Paw San Hmwe （PSM） rice has been cultivated in many areas of Myanmar for a long time. Strong aroma, good taste and its elongation during cooking are the key characteristics of PSM rice. Thirty-one PSM accessions were genotypically characterized, and their physical grain and cooking quality traits were studied. We used specific gene markers associated with aroma, apparent amylose content （AAC） and alkali spreading value to determine the alleles carried by different PSM accessions. The results revealed that six PSM accessions （PSM10, PSM12, PSM13, PSM21, PSM22 and PSM30） had a 3-bp insertion in Os2AP gene. Gel consistency （GC） allele was predominant among the PSM accessions for gelatinization temperature （GT）, however, the phenotype observed was between low and intermediate GT because of the combination of the GC allele with the presence of low GT allele at heterozygous state from the other loci of the SSIla gene. Intermediate to high AAC was observed among the PSM accessions corresponding to the haplotype identified for the single nucleotide polymorphism G/T and the （Cm）n repeat in the Wx gene. The characterization and grouping data of PSM accessions posted benefits to Myanmar seed banks, and our results will help in maintaining the integrity of PSM rice variety.
基金supported by the Tana Group International Co.Ltd.,Thailand(2015-2019).
文摘Breeding program strategies to develop novel short grain white rice varieties such as japonica(short grain)that introgress biotic stress resistance and high grain quality have been developed usingindica rice(Pin Kaset+4 and Riceberry)for applications in japonica rice(Kashihikari)improvement.Fourbreeding lines showing promising agronomic performance with short grain and low amylose content(<20%)were obtained.In addition,sensory testing of these breeding lines showed high scores thatsimilar to Kashihikari.Two promising lines,KP48-1-5and KP48-1-9,which possessed a combination offour genes resistance to different biotic stresses(Bph3+TPS+Xa21+Pi-ta)and four genes for grainquality(G83+SSlla+w+badh2),were deveiaped using marker-assisted selection(MAS)with thepedigree method.The current study clearly illustrated the successful use of MAS in combining resistanceto multiple biotic stresses while maintaining a high yield potential and preferred grain quality.Moreover,the results indicated that this breeding program,which includes crossing temperate japonica with indica,can create novel short grain rice varieties adapted to a trapical environment like the japonica type.
基金the funds from the National Key Research and Development Plan of China(Grant No.2017YFD0100305).
文摘In order to create novel germplasm resources for breeding heat tolerant variety,we transferred a dominant allele OsHTAS,previously characterized and cloned from a high-temperature tolerant local variety HT54,which was collected from the rice production area of southern China,into a high-temperature sensitive intermediate breeding line HT13 through six rounds of successive backcross by using marker-assisted selection.The molecular analysis showed that the recovery of genetic background of a resultant near isogenic line(NIL),MHT13,was around 99.8%.The OsHTAS gene introduced in the MHT13 expressed normally in the HT13 genetic background,mediating heat tolerance and phenotype similar to those of the donor parent HT54.The major agronomic traits of MHT13 resembled those of the recurrent parent HT13.Moreover,MHT13 had high general combining ability and its rice quality reached the grade 3 standard of edible high-quality rice issued by Ministry of Agriculture of the People’s Republic of China,which greatly improved its application value in rice production.
基金funded by Bangladesh Wheat and Maize Research Institute(BWMRI),Dinajpur 5200,Bangladeshthe Taif University Researchers Supporting Project(TURSP-2020/143),Taif,Saudi Arabia。
文摘Globally among biotic stresses,diseases like blight,rust and blast constitute prime constraints for reducing wheat productivity especially in Bangladesh.For sustainable productivity,the development of disease-resistant lines and high yielding varieties is vital and necessary.This study was conducted using 122 advanced breeding lines of wheat including 21 varieties developed by Bangladesh Wheat and Maize Research Institute with aims to identify genotypes having high yield potential and resistant to leaf blight,leaf rust and blast diseases.These genotypes were evaluated for resistance against leaf blight and leaf rust at Dinajpur and wheat blast at Jashore under field condition.Out of 122 genotypes tested,20 lines were selected as resistant to leaf blight based on the area under the diseases progress curve under both irrigated timely sown and irrigated late sown conditions.Forty-two genotypes were found completely free from leaf rust infection,59 genotypes were identified as resistant,and 13 genotypes were identified as moderately resistant to leaf rust.Eighteen genotypes were immune against wheat blast,42 genotypes were categorized as resistant,and 26 genotypes were identified as moderately resistant to wheat blast.Molecular data revealed that the 16 genotypes showed a positive 2NS segment among the 18 immune genotypes selected against wheat blast under field conditions.The genotypes BAW 1322,BAW 1295,and BAW 1203 can be used as earlier maturing genotypes and the genotypes BAW 1372,BAW 1373,BAW 1297 and BAW 1364 can be used for lodging tolerant due to short plant height.The genotypes WMRI Gom 1,BAW 1349 and BAW 1350 can be selected for bold grain and the genotypes WMRI Gom 1,BAW 1297,BAW 1377 can be used as high yielder for optimum seeding condition but genotypes BAW 1377 and BAW 1366 can be used for late sown condition.The selected resistant genotypes against specific diseases can be used in the further breeding program to develop wheat varieties having higher disease resistance and yield potential.
文摘In China,the market share of a rice cultivar is mainly determined by its yield and quality.Yuzhenxiang is a high-quality variety with extra-slender grain shape,good quality and unique aroma.In order to investigate its genetic background,12 pairs of functional markers were used to detect the genotype distribution of eight major grain shape genes including GS3,GW5,GS6,GW6a,GL7/GW7,GLW7,GW8,GS9,one amylase gene Wx and one aroma gene BADH2 in Yuzhenxiang by using Nipponbare,9311,Huazhan,Zhonghui 8015 and Zhonghui 9308 as controls.The results indicated that the slender grain type of Yuzhenxiang was probably affected by GS3 and GL7/GW7 with the positive co-regulation of multiple grain shape genes,and its outstanding rice quality may be resulted from the cumulative effects of GLW7,GW8 and Wx genotypes,while its unique aroma may be mainly regulated by BADH2-E7 deletion.
基金supported by the Ministry of Science and Technology(Grant No. 2011 CB 100205)the Ministry of Agriculture of China (Grant Nos.2011ZX08001-004 and 2011ZX08009-002)the National Natural Science Foundation of China(Grant No. 31121063)
文摘1000-Grain weight and spikelet number per panicle are two important components for rice grain yield. In our previous study, eight quantitative trait loci （QTLs） conferring spikelet number per panicle and 1000-grain weight were mapped through sequencing-based genotyping of 150 rice recombinant inbred lines （RILs）. In this study, we validated the effects of four QTLs from Nipponbare using chromosome segment substitution lines （CSSLs）, and pyramided eight grain yield related QTLs. The new lines containing the eight QTLs with positive effects showed increased panicle and spikelet size as compared with the parent variety 93-11. We further proposed a novel pyramid breeding scheme based on marker-assistant and phenotype selection （MAPS）. This scheme allowed pyramiding of as many as 24 QTLs at a single hybridization without massive cross work. This study provided insights into the molecular basis of rice grain yield for direct wealth for high-yielding rice breeding.
