Increasing wheat yield is a long-term goal for wheat breeders around the world.Exploiting elite genetic resources and dissecting the genetic basis of important agronomic traits in wheat are the necessary methods for h...Increasing wheat yield is a long-term goal for wheat breeders around the world.Exploiting elite genetic resources and dissecting the genetic basis of important agronomic traits in wheat are the necessary methods for high-yield wheat breeding.This study evaluated nine crucial agronomic traits found in a natural population of 156 wheat varieties and77 landraces from Sichuan,China in seven environments over two years.The results of this investigation of agronomic traits showed that the landraces had more tillers and higher kernel numbers per spike (KNS),while the breeding varieties had higher thousand-kernel weight (TKW) and kernel weight per spike (KWS).The generalized heritability (H2) values of the nine agronomic traits varied from 0.74 to 0.95.Structure analysis suggested that the natural population could be divided into three groups using 43 198 single nucleotide polymorphism (SNP) markers from the wheat 55K SNP chip.A total of 67 quantitative trait loci (QTLs) were identified by the genome-wide association study (GWAS) analysis based on the Q+K method of a mixed linear model.Three important QTLs were analyzed in this study.Four haplotypes of QFTN.sicau-7BL.1 for fertile tillers number (FTN),three haplotypes of QKNS.sicau-1AL.2 for KNS,and four haplotypes of QTKW.sicau-3BS.1 for TKW were detected.FTN-Hap2,KNS-Hap1,and TKW-Hap2 were excellent haplotypes for each QTL based on the yield performance of 42 varieties in regional trials from 2002 to 2013.The varieties with all three haplotypes showed the highest yield compared to those with either two haplotypes or one haplotype.In addition,the KASP-AX-108866053 marker of QTL QKNS.sicau-1AL.2 was successfully distinguished between three haplotypes(or alleles) in 63 varieties based on the number of kernels per spike in regional trials between 2018 and 2021.These genetic loci and reliable makers can be applied in marker-assisted selection or map-based gene cloning for the genetic improvement of wheat yield.展开更多
Soils play a critical role in the global carbon cycle, and can be major source or sink of CO2 depending upon land use, vegetation type and soil management practices. Fine roots are important component of a forest ecos...Soils play a critical role in the global carbon cycle, and can be major source or sink of CO2 depending upon land use, vegetation type and soil management practices. Fine roots are important component of a forest ecosystem in terms of water and nutrient uptake. In this study the effects of thinning and litter fall removal on fine root production and soil organic carbon content were examined in 20-year-old Masson pine (Pinus resinosa) plantations in Huitong, Hunan Province of China in the growing seasons of 2004 and 2005. The results showed that fine root production was significantly lower in the thinning plots than in the control plots, with a decrease of 58% and 14% in 2004 and 2005 growing seasons, respectively. Litter fall removal significantly increased fine root production by 14% in 2004. Soil temperature (Tsoil) and soil moisture (Msoil) were higher in the thinning plots than those in the controls. Litter fall removal had significant effiects on Tsoil and Msoil. Soil organic carbon content was higher in the thinning plots but was lower in the plots with litter fall removal compared with that in the controls. Our results also indicated that annual production of fine roots resulted in small carbon accumulation in the upper layers of the soil, and removal of tree by thinning resulted in a significant increase of carbon storage in Masson pine plantations.展开更多
Researches on the relationship between photosynthesis and wheat yield have equally attracted the attention of both domestic and overseas scholars. No report has existed so far on the study of the effects of exogenous ...Researches on the relationship between photosynthesis and wheat yield have equally attracted the attention of both domestic and overseas scholars. No report has existed so far on the study of the effects of exogenous chromosomes on photosynthesis using the substitution series as materials. In this research, Triticum aestivum cv. Chinese Spring-Lophopyrum elongatum （Host） A.Loeve disomic substitution series were used as materials and flag leaves as the measuring position. And the CI-310 Portable Photosynthesis System made by CID Co. in USA was used to measure the net rate of photosynthesis of flag leaves in different developing stages and also to correlate photosynthesis with yield. Results showed that, out of the whole developing stages, at the anthesis stage the line of DS2Ee （2A） had the highest photosynthetic rate, therefore it could be used in improving process of the character of kernel number. The flag leaves of DS4Ee （4A, 4B, 4D） lines demonstrated certain high net photosynthetic rate from heading to grain filling stage, so it is valuable in the researh of promoting the yield index like 1 000-grain weight through improvement of the photosynthetic rate at grain filling stage.展开更多
The flux of carbon dioxide(CO2) from soil surface presents an important component of carbon(C) cycle in terrestrial ecosystems and is controlled by a number of biotic and abiotic factors. In order to better understand...The flux of carbon dioxide(CO2) from soil surface presents an important component of carbon(C) cycle in terrestrial ecosystems and is controlled by a number of biotic and abiotic factors. In order to better understand characteristics of soil CO2 flux(FCO2) in subtropical forests,soil FCO2 rates were quantified in five adjacent forest types(camphor tree forest,Masson pine forest,mixed camphor tree and Masson pine forest,Chinese sweet gum forest,and slash pine forest) at the Tianjiling National Park in Changsha,Hunan Province,in subtropical China,from January to December 2010. The influences of soil temperature(Tsoil),volumetric soil water content(θsoil),soil pH,soil organic carbon(SOC) and soil C/nitrogen(N) ratio on soil FCO2 rates were also investigated. The annual mean soil FCO2 rate varied with the forest types. The soil FCO2 rate was the highest in the camphor tree forest(3.53 ± 0.51 μmol m-2s-1),followed by,in order,the mixed,Masson pine,Chinese sweet gum,and slash pine forests(1.53 ± 0.25 μmol m-2 s1). Soil FCO2 rates from the five forest types followed a similar seasonal pattern with the maximum values occurring in summer(July and August) and the minimum values during winter(December and January). Soil FCO2 rates were correlated to Tsoiland θsoil,but the relationships were only significant for Tsoil. No correlations were found between soil FCO2 rates and other selected soil properties,such as soil pH,SOC,and C/N ratio,in the examined forest types. Our results indicated that soil FCO2 rates were much higher in the evergreen broadleaved forest than coniferous forest under the same microclimatic environment in the study region.展开更多
基金supported by the Sichuan Science and Technology Program , China ( 2022ZDZX0014 and 2021YFYZ0002)the Plan of Tianfu Qingcheng of Sichuan Province, China。
文摘Increasing wheat yield is a long-term goal for wheat breeders around the world.Exploiting elite genetic resources and dissecting the genetic basis of important agronomic traits in wheat are the necessary methods for high-yield wheat breeding.This study evaluated nine crucial agronomic traits found in a natural population of 156 wheat varieties and77 landraces from Sichuan,China in seven environments over two years.The results of this investigation of agronomic traits showed that the landraces had more tillers and higher kernel numbers per spike (KNS),while the breeding varieties had higher thousand-kernel weight (TKW) and kernel weight per spike (KWS).The generalized heritability (H2) values of the nine agronomic traits varied from 0.74 to 0.95.Structure analysis suggested that the natural population could be divided into three groups using 43 198 single nucleotide polymorphism (SNP) markers from the wheat 55K SNP chip.A total of 67 quantitative trait loci (QTLs) were identified by the genome-wide association study (GWAS) analysis based on the Q+K method of a mixed linear model.Three important QTLs were analyzed in this study.Four haplotypes of QFTN.sicau-7BL.1 for fertile tillers number (FTN),three haplotypes of QKNS.sicau-1AL.2 for KNS,and four haplotypes of QTKW.sicau-3BS.1 for TKW were detected.FTN-Hap2,KNS-Hap1,and TKW-Hap2 were excellent haplotypes for each QTL based on the yield performance of 42 varieties in regional trials from 2002 to 2013.The varieties with all three haplotypes showed the highest yield compared to those with either two haplotypes or one haplotype.In addition,the KASP-AX-108866053 marker of QTL QKNS.sicau-1AL.2 was successfully distinguished between three haplotypes(or alleles) in 63 varieties based on the number of kernels per spike in regional trials between 2018 and 2021.These genetic loci and reliable makers can be applied in marker-assisted selection or map-based gene cloning for the genetic improvement of wheat yield.
基金Supported by the "948" Grant of the National Forestry Administration of China (No.2007-4-19)the Special Grantof Chinese Forestry Public Benefits (Nos.200804030 and 2007-4-15)the Provincial Fund for Distinguished Young Scholars of Hunan, China (No.07JJ1004)
文摘Soils play a critical role in the global carbon cycle, and can be major source or sink of CO2 depending upon land use, vegetation type and soil management practices. Fine roots are important component of a forest ecosystem in terms of water and nutrient uptake. In this study the effects of thinning and litter fall removal on fine root production and soil organic carbon content were examined in 20-year-old Masson pine (Pinus resinosa) plantations in Huitong, Hunan Province of China in the growing seasons of 2004 and 2005. The results showed that fine root production was significantly lower in the thinning plots than in the control plots, with a decrease of 58% and 14% in 2004 and 2005 growing seasons, respectively. Litter fall removal significantly increased fine root production by 14% in 2004. Soil temperature (Tsoil) and soil moisture (Msoil) were higher in the thinning plots than those in the controls. Litter fall removal had significant effiects on Tsoil and Msoil. Soil organic carbon content was higher in the thinning plots but was lower in the plots with litter fall removal compared with that in the controls. Our results also indicated that annual production of fine roots resulted in small carbon accumulation in the upper layers of the soil, and removal of tree by thinning resulted in a significant increase of carbon storage in Masson pine plantations.
文摘Researches on the relationship between photosynthesis and wheat yield have equally attracted the attention of both domestic and overseas scholars. No report has existed so far on the study of the effects of exogenous chromosomes on photosynthesis using the substitution series as materials. In this research, Triticum aestivum cv. Chinese Spring-Lophopyrum elongatum （Host） A.Loeve disomic substitution series were used as materials and flag leaves as the measuring position. And the CI-310 Portable Photosynthesis System made by CID Co. in USA was used to measure the net rate of photosynthesis of flag leaves in different developing stages and also to correlate photosynthesis with yield. Results showed that, out of the whole developing stages, at the anthesis stage the line of DS2Ee （2A） had the highest photosynthetic rate, therefore it could be used in improving process of the character of kernel number. The flag leaves of DS4Ee （4A, 4B, 4D） lines demonstrated certain high net photosynthetic rate from heading to grain filling stage, so it is valuable in the researh of promoting the yield index like 1 000-grain weight through improvement of the photosynthetic rate at grain filling stage.
基金Supported by the National Forestry Public Welfare Research Program of China(Nos.201104005 and 200804030)the Program for New Century Excellent Talents in University of Ministry of Education of China(No.NCET-10-0151)+1 种基金the 100 Talents Program of Hunan Province,China(No.2011516)Central South University of Forestry and Technology,China(No.0842)
文摘The flux of carbon dioxide(CO2) from soil surface presents an important component of carbon(C) cycle in terrestrial ecosystems and is controlled by a number of biotic and abiotic factors. In order to better understand characteristics of soil CO2 flux(FCO2) in subtropical forests,soil FCO2 rates were quantified in five adjacent forest types(camphor tree forest,Masson pine forest,mixed camphor tree and Masson pine forest,Chinese sweet gum forest,and slash pine forest) at the Tianjiling National Park in Changsha,Hunan Province,in subtropical China,from January to December 2010. The influences of soil temperature(Tsoil),volumetric soil water content(θsoil),soil pH,soil organic carbon(SOC) and soil C/nitrogen(N) ratio on soil FCO2 rates were also investigated. The annual mean soil FCO2 rate varied with the forest types. The soil FCO2 rate was the highest in the camphor tree forest(3.53 ± 0.51 μmol m-2s-1),followed by,in order,the mixed,Masson pine,Chinese sweet gum,and slash pine forests(1.53 ± 0.25 μmol m-2 s1). Soil FCO2 rates from the five forest types followed a similar seasonal pattern with the maximum values occurring in summer(July and August) and the minimum values during winter(December and January). Soil FCO2 rates were correlated to Tsoiland θsoil,but the relationships were only significant for Tsoil. No correlations were found between soil FCO2 rates and other selected soil properties,such as soil pH,SOC,and C/N ratio,in the examined forest types. Our results indicated that soil FCO2 rates were much higher in the evergreen broadleaved forest than coniferous forest under the same microclimatic environment in the study region.
