Exploring the elite al eles and germplasm acces-sions related to fiber quality traits wil accelerate the breeding of cotton for fiber quality improvement. In this study, 99 Gossypium hirsutum L. accessions with divers...Exploring the elite al eles and germplasm acces-sions related to fiber quality traits wil accelerate the breeding of cotton for fiber quality improvement. In this study, 99 Gossypium hirsutum L. accessions with diverse origins were used to perform association analysis of fiber quality traits using 97 polymorphic microsatel ite marker primer pairs. A total of 107 significant marker-trait associations were detected for three fiber quality traits under three different environments, with 70 detected in two or three environments and 37 detected in only one environment. Among the 70 significant marker-trait associations, 52.86% were reported previously, implying that these are stable loci for target traits. Furthermore, we detected a large number of elite al eles associated simulta-neously with two or three traits. These elite al eles were mainly from accessions col ected in China, introduced to China from the United States, or rare al eles with a frequency of less than＆amp;nbsp;5%. No one cultivar contained more than half of the elite al eles, but 10 accessions were col ected from China and the two introduced from the United States did contain more than half of these al eles. Therefore, there is great potential for mining elite al eles from germplasm accessions for use in fiber quality improvement in modern cotton breeding.展开更多
Yellowhorn （Xanthoceras sorbifolium Bunge） is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple se...Yellowhorn （Xanthoceras sorbifolium Bunge） is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple sequence repeat （ISSR） analysis showed genetic variation among four artificial populations in China： two in Inner Mongolia （IM）, one in Liaoning （LN）, and one in Shandong （SD）. The average percentage of polymorphic loci was 81.25 % for these four populations. The Forest Farm in SD showed the highest number of effective alleles （Ne）, Shannon index （I）, and expected heterozygosity （He）, i.e., 1.598, 0.470, and 0.325, respectively, but the lowest number of alleles （Na） as 1.600. Based on an analysis of molecular variance, 23 % of the total genetic variation was found among populations, and 77 % within populations. A principal coordinate analysis revealed two groups （Group 1： Lindonglinchang, Jianping Agriculture Research Station and Forest Farm; Group 2： Jinjilinchang）. Understanding the genetic diversity among artificial yellowhorn populations in China, detected using ISSRs, will be useful for yellowhorn conservation and improvement. Additional arti-ficial and natural populations need to be included in the future for a country-wide perspective.展开更多
Cultivated peanut is grown worldwide as rich- source of oil and protein. A broad genetic base is needed for cultivar improvement. The objectives of this study were to develop highly informative simple sequence repeat ...Cultivated peanut is grown worldwide as rich- source of oil and protein. A broad genetic base is needed for cultivar improvement. The objectives of this study were to develop highly informative simple sequence repeat （SSR） markers and to assess the genetic diversity and popuJation structure of peanut cultivars and breeding lines from different breeding programs in China, India and the US. A total of 111 SSR markers were selected for this study, resulting in a total of 472 alleles. The mean values of gene diversity and polymorphic information content （PIC） were 0.480 and o.429, respectively. Country-wise analysis revealed that alleles per locus in three countries were similar. The mean gene diversity in the US, China and India was 0.363, o.489 and 0.47 with an average PIC of 0.323, 0.43 and o.412, respectively. Genetic analysis using the STRUCTURE divided these peanut lines into two populations （P1, P2）, which was consistent with the dendro- gram based on genetic distance （G1, G2） and the clustering of principal component analysis. The groupings were related to peanut market types and the geographic origin with a few admixtures. The results could be used by breeding programs to assess the genetic diversity of breeding materials to broaden the genetic base and for molecular genetics studies.展开更多
Background： The ＇Khasi hill sal＇ forest ecosystem in Meghalaya, India represents the easternmost limit of sal distribution. We tested if tree diversity and compositional heterogeneity of this ecosystem was higher t...Background： The ＇Khasi hill sal＇ forest ecosystem in Meghalaya, India represents the easternmost limit of sal distribution. We tested if tree diversity and compositional heterogeneity of this ecosystem was higher than other sal-dominated forests due to moister environment. Methods： Vegetation was sampled in 11 transects of 10 m width and up to 500 m length covering 5.2 ha area. All stems ≥10 cm girth at breast height were enumerated. Results： We found a pattern of mixed dominance of Shored robusta （sal） and Schima wollichii and co-dominance of Pinus kesiyo and Careya arborea. The Shannon＇s diversity index （H＇） was 3.395 nats. This value is remarkably high and competitive to that of moist sal forests of eastern Himalayan foothills and sal-dominated forests of Tripura. A high value of H＇ was manifested by： a） high species richness （S = 123）, b） good equitability （70.6%）, c） ＇fair＇ resource apportionment, and d） abundance of rare species （84% species with less than one per cent of total individuals, 67% species with two or less individuals ha-1 and 59% species with one or less individuals ha-1）. The compositional heterogeneity was ＇fair＇ （Whittaker＇sβw = 3.15）. The presence of Fagaceae with six species commanding 4.3% of importance value （IVl） and of a pine （P. kesiya） in sal forest was remarkable. As many as 58 species showed ＇low density （〈 10 individuals ha-1）, uniform dispersion＇, five species achieved ＇higher density （〉 10 individuals ha-l）, uniform dispersion＇ and six of the top 10 species were ＇clumped＇. The forest showed an exponential demographic curve illustrating ＇good＇ regeneration of an expanding community. Vertical stratification was simple with a poor canopy and fair subcanopy, which together with low basal area （15.65 m2 . ha-1 for individuals ≥ 10 cm gbh） indicated logging of mature sal trees in the past. Conclusions： The ＇Khasi hill sal＇ forest ecosystem is richer in alpha and beta diversi展开更多
Forest vegetation of a protected area （Binsar Wildlife Sanctuary） in Kumaun region （west Himalaya） was analysed for structure, composition and representativeness across three different altitudinal belts, lower （1...Forest vegetation of a protected area （Binsar Wildlife Sanctuary） in Kumaun region （west Himalaya） was analysed for structure, composition and representativeness across three different altitudinal belts, lower （1,6oo-1,8oo m a.s.1.）, middle （1,900-2,100 m a.s.1.） and upper （2,200-2,400 m a.s.1.） during 2oo9-2011 using standard phytosociological methods. Four aspects （east, west, north and south） in each altitudinal belt were chosen for sampling to depict maximum representation of vegetation in the sanctuary. Population structure and regeneration behaviour was analysed seasonally for two years to show the establishment and growth of tree species. A total of 147 plant species were recorded from the entire region of which 27 tree species were selected for detailed study. Highest number was recorded at upper （18 species）, and lowest at lower altitudinal belt （15 species）. The relative proportion of species richness showed higher contribution of tree layer at each altitudinal belt. The population structure, based on the number of individuals, revealed a greater proportion of seedling layer at each altitudinal belt. The relative proportion of seedlings increases significantly along altitudinal belts （p〈0.05） while opposite trends were observed in sapling and tree layers. The density of sapling and seedling species varied non-significantly across seasons （p〉0.05）. The density values decreased in summer and increased during rainy season. As far as the regeneration status is concerned, middle and upper altitudinal belts showed maximum number of species with fair regeneration as compared to lower altitudinal belt. Overall density diameter distribution of tree species showed highest species density and richness in the smallest girth class and decreased in the succeeding girth classes. This study suggests that patterns of regeneration behaviour would determine future structural and compositional changes in the forest communities. It is suggested that the compositional changes vis-a展开更多
基金financially supported in part by the National Science Foundation in China(30871558)the National High Technology Research and Development Program of China(863 Program)(2012AA101108-04-04)+1 种基金Jiangsu Agriculture Science and Technology Innovation Fund(cx(13)3059)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Exploring the elite al eles and germplasm acces-sions related to fiber quality traits wil accelerate the breeding of cotton for fiber quality improvement. In this study, 99 Gossypium hirsutum L. accessions with diverse origins were used to perform association analysis of fiber quality traits using 97 polymorphic microsatel ite marker primer pairs. A total of 107 significant marker-trait associations were detected for three fiber quality traits under three different environments, with 70 detected in two or three environments and 37 detected in only one environment. Among the 70 significant marker-trait associations, 52.86% were reported previously, implying that these are stable loci for target traits. Furthermore, we detected a large number of elite al eles associated simulta-neously with two or three traits. These elite al eles were mainly from accessions col ected in China, introduced to China from the United States, or rare al eles with a frequency of less than＆amp;nbsp;5%. No one cultivar contained more than half of the elite al eles, but 10 accessions were col ected from China and the two introduced from the United States did contain more than half of these al eles. Therefore, there is great potential for mining elite al eles from germplasm accessions for use in fiber quality improvement in modern cotton breeding.
基金supported by the Cooperative Research Program for Agriculture Science & Technology Development(Project no.PJ01117902) of the National Institute of Horticultural and Herbal Science,RDA,Republic of Koreathe Ministry of Education,People’s Republic of China(Program No.MS2012DBLY017 for Foreign Distinguished Scientists of the Ministry of Education)the Research Foundation of Kangwon National University,Republic of Korea
文摘Yellowhorn （Xanthoceras sorbifolium Bunge） is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple sequence repeat （ISSR） analysis showed genetic variation among four artificial populations in China： two in Inner Mongolia （IM）, one in Liaoning （LN）, and one in Shandong （SD）. The average percentage of polymorphic loci was 81.25 % for these four populations. The Forest Farm in SD showed the highest number of effective alleles （Ne）, Shannon index （I）, and expected heterozygosity （He）, i.e., 1.598, 0.470, and 0.325, respectively, but the lowest number of alleles （Na） as 1.600. Based on an analysis of molecular variance, 23 % of the total genetic variation was found among populations, and 77 % within populations. A principal coordinate analysis revealed two groups （Group 1： Lindonglinchang, Jianping Agriculture Research Station and Forest Farm; Group 2： Jinjilinchang）. Understanding the genetic diversity among artificial yellowhorn populations in China, detected using ISSRs, will be useful for yellowhorn conservation and improvement. Additional arti-ficial and natural populations need to be included in the future for a country-wide perspective.
基金supported by the US Department of Agriculture Agricultural Research Service(USDA-ARS)the Georgia Agricultural Commodity Commission for Peanuts+1 种基金Peanut Foundation and National Peanut Boardpart of the CGIAR Research Program on Grain Legumes and USAID University Linkage Grant
文摘Cultivated peanut is grown worldwide as rich- source of oil and protein. A broad genetic base is needed for cultivar improvement. The objectives of this study were to develop highly informative simple sequence repeat （SSR） markers and to assess the genetic diversity and popuJation structure of peanut cultivars and breeding lines from different breeding programs in China, India and the US. A total of 111 SSR markers were selected for this study, resulting in a total of 472 alleles. The mean values of gene diversity and polymorphic information content （PIC） were 0.480 and o.429, respectively. Country-wise analysis revealed that alleles per locus in three countries were similar. The mean gene diversity in the US, China and India was 0.363, o.489 and 0.47 with an average PIC of 0.323, 0.43 and o.412, respectively. Genetic analysis using the STRUCTURE divided these peanut lines into two populations （P1, P2）, which was consistent with the dendro- gram based on genetic distance （G1, G2） and the clustering of principal component analysis. The groupings were related to peanut market types and the geographic origin with a few admixtures. The results could be used by breeding programs to assess the genetic diversity of breeding materials to broaden the genetic base and for molecular genetics studies.
基金Department of Biotechnology (DBT), Government of India, New Delhi provided principal funding for this work through a project grant to US (grant number BT/PR7928/NDB/52/9/2006)
文摘Background： The ＇Khasi hill sal＇ forest ecosystem in Meghalaya, India represents the easternmost limit of sal distribution. We tested if tree diversity and compositional heterogeneity of this ecosystem was higher than other sal-dominated forests due to moister environment. Methods： Vegetation was sampled in 11 transects of 10 m width and up to 500 m length covering 5.2 ha area. All stems ≥10 cm girth at breast height were enumerated. Results： We found a pattern of mixed dominance of Shored robusta （sal） and Schima wollichii and co-dominance of Pinus kesiyo and Careya arborea. The Shannon＇s diversity index （H＇） was 3.395 nats. This value is remarkably high and competitive to that of moist sal forests of eastern Himalayan foothills and sal-dominated forests of Tripura. A high value of H＇ was manifested by： a） high species richness （S = 123）, b） good equitability （70.6%）, c） ＇fair＇ resource apportionment, and d） abundance of rare species （84% species with less than one per cent of total individuals, 67% species with two or less individuals ha-1 and 59% species with one or less individuals ha-1）. The compositional heterogeneity was ＇fair＇ （Whittaker＇sβw = 3.15）. The presence of Fagaceae with six species commanding 4.3% of importance value （IVl） and of a pine （P. kesiya） in sal forest was remarkable. As many as 58 species showed ＇low density （〈 10 individuals ha-1）, uniform dispersion＇, five species achieved ＇higher density （〉 10 individuals ha-l）, uniform dispersion＇ and six of the top 10 species were ＇clumped＇. The forest showed an exponential demographic curve illustrating ＇good＇ regeneration of an expanding community. Vertical stratification was simple with a poor canopy and fair subcanopy, which together with low basal area （15.65 m2 . ha-1 for individuals ≥ 10 cm gbh） indicated logging of mature sal trees in the past. Conclusions： The ＇Khasi hill sal＇ forest ecosystem is richer in alpha and beta diversi
基金Council of Scientific and Industrial Research (CSIR) (File No: 09/560(0015)/2011-EMR-I)India and OCB programme of UNU, Tokyo, Japan for financial support to Balwant Rawat and Vikram Negi
文摘Forest vegetation of a protected area （Binsar Wildlife Sanctuary） in Kumaun region （west Himalaya） was analysed for structure, composition and representativeness across three different altitudinal belts, lower （1,6oo-1,8oo m a.s.1.）, middle （1,900-2,100 m a.s.1.） and upper （2,200-2,400 m a.s.1.） during 2oo9-2011 using standard phytosociological methods. Four aspects （east, west, north and south） in each altitudinal belt were chosen for sampling to depict maximum representation of vegetation in the sanctuary. Population structure and regeneration behaviour was analysed seasonally for two years to show the establishment and growth of tree species. A total of 147 plant species were recorded from the entire region of which 27 tree species were selected for detailed study. Highest number was recorded at upper （18 species）, and lowest at lower altitudinal belt （15 species）. The relative proportion of species richness showed higher contribution of tree layer at each altitudinal belt. The population structure, based on the number of individuals, revealed a greater proportion of seedling layer at each altitudinal belt. The relative proportion of seedlings increases significantly along altitudinal belts （p〈0.05） while opposite trends were observed in sapling and tree layers. The density of sapling and seedling species varied non-significantly across seasons （p〉0.05）. The density values decreased in summer and increased during rainy season. As far as the regeneration status is concerned, middle and upper altitudinal belts showed maximum number of species with fair regeneration as compared to lower altitudinal belt. Overall density diameter distribution of tree species showed highest species density and richness in the smallest girth class and decreased in the succeeding girth classes. This study suggests that patterns of regeneration behaviour would determine future structural and compositional changes in the forest communities. It is suggested that the compositional changes vis-a
