Jute mallow is a nutritious leafy vegetable. The leaves are rich in proteins, vitamins and essential amino acids. Molecular characterization of Jute mallow with focus on improvement of leaf yield is scarcely reported....Jute mallow is a nutritious leafy vegetable. The leaves are rich in proteins, vitamins and essential amino acids. Molecular characterization of Jute mallow with focus on improvement of leaf yield is scarcely reported. In the present study, inter sequence simple repeats (ISSR) molecular markers were employed to assess genetic diversity and relationships of 83 accessions of Jute mallow from different parts of Africa and Asia conserved at the World Vegetable Center East and Southern Africa. A total of 89 bands were amplified by 8 ISSR primers. Number of polymorphic bands per primer ranged from 2 to 6 with an average of 2.75 bands per primer. Polymorphic information content (PIC) values ranged from 0.390 to 0.760 with average of 0.53. Average Nei’s gene diversity (h) and Shannon’s information index (I) were 0.335 and 0.494 respectively. The highest pairwise genetic distance was 0.431 observed in a population from East Africa accessions. PC1 and PC2 axis explained 21.69% and 11.66% of the total variation respectively. UPGMA cluster analysis grouped the accessions into six main clusters at genetic similarity coefficient of 0.53 as standard value for classification. These results have important implications for jute mallow breeding and conservation.展开更多
Larix resources in the Qinghai-Tibet Plateau have important ecological and economic values.However,the lack of genetic diversity background and related research hinders the development of conservation strategies.In th...Larix resources in the Qinghai-Tibet Plateau have important ecological and economic values.However,the lack of genetic diversity background and related research hinders the development of conservation strategies.In this study,genetic diversity and distribution of fi ve Larix species were investigated.Using 19 polymorphic microsatellite markers to study 272 representative individuals from 13 populations,the results show low genetic diversity at the population level,with variation explained mainly by diff erentiation among populations.The Larix populations were classifi ed into two clades,one formed by eight populations,including three of the species in this study,L.kongboensis,L.speciosa,and L.potaninii var.australis.The other clade consists of fi ve populations,including the other two species in this study,L.griffi thii and L.himalaica.Genetic distance of the species was aff ected by geographical isolation and genetic diversity was mainly aff ected by altitude.The area suitable for Larix spp.decreased during the Last Glacial Maximum compared to the current distribution according to the niche model,but should increase in future climate scenarios(2050s),expanding westward along the Himalayas.These results provide an important scientifi c basis for the development of conservation strategies and further the sustainable utilization of Larix resources in the Qinghai-Tibet Plateau.展开更多
Pepper（Capsicum spp.） is an important vegetable crop in the world. Now the pepper in China contributes one-third of the world＇s peppers production. Genetic diversity of the pepper germplasm of China is expected int...Pepper（Capsicum spp.） is an important vegetable crop in the world. Now the pepper in China contributes one-third of the world＇s peppers production. Genetic diversity of the pepper germplasm of China is expected interesting to know. To explore the structure of genetic diversity in Chinese pepper germplasm resources and possible relationship with cultivar types or geographic origin, we sampled and compared 372 Gen Bank pepper accessions（local cultivars and landraces） from 31 provinces, autonomous regions and municipalities of China and 31 additional accessions from other countries. These accessions were genotyped using 28 simple sequence repeat（SSR） markers spanning the entire pepper genome. We then investigated the genetic structure of the sampled collection using model-based analysis in STRUCTURE v2.3.4 and examined genetic relationships by the unweighted pair-group method of mathematical averages（UPGMA） in MEGA. In addition to geographic origin, we evaluated eight plant and fruit traits. In total, 363 alleles were amplified using the 28 SSR primers. Gene diversity, polymorphism information content and heterozygosity of the 28 SSR loci were estimated as 0.09–0.92, 0.08–0.92 and 0.01–0.34, respectively. The UPGMA cluster analysis clearly distinguished Capsicum annuum L. from other cultivated pepper species. Population structure analysis of the 368 C. annuum accessions uncovered three genetic groups which also corresponded to distinct cultivar types with respect to the plant and fruit descriptors. The genetic structure was also related to the geographic origin of the landraces. Overall results indicate that genetic diversity of Chinese pepper landraces were structured by migration of genotypes followed by human selection for cultivar types in agreement with consumption modes and adaptation to the highly diversified agro-climatic conditions.展开更多
The genetic diversity from species of the genus Jatropha collected from Costa Rica was analyzed by AFLP (amplified fragments length polymorphism). The study consisted of 114 accessions from 15 populations of 4 differe...The genetic diversity from species of the genus Jatropha collected from Costa Rica was analyzed by AFLP (amplified fragments length polymorphism). The study consisted of 114 accessions from 15 populations of 4 different species: J. curcas, J. costaricensis, J. gossypifolia and J. stevensii. These were collected from different locations in Costa Rica. Three different primers were used, resulting in 428 loci, and they were classified in three categories: unique and double bands (UBD), rare bands (RB) and shared bands (SB). The UBD were excluded for a total of 339 polymorphic loci used for the UPGMA dendrogram and principal component analysis (PCA). The species that obtained the highest average of polymorphic loci was J. curcas, which obtained the highest percentage of polymorphic loci (80.24%), followed by J. gossypifolia (79.35%), J. costaricensis (78.76%), and finally J. stevensii (40.71%). The average for the polymorphic loci was of 69.76%. Thus, the phylogeny of the Jatropha species in Costa Rica was elucidated, showing J. curcas more related to J. stevensii and this one with J. costaricensis, and J. gossypifolia as the most distant member of the genus. For the best of our knowledge this is the first report of a genetic analysis of J. costaricensis and J. stevensii. The obtained molecular evidence showed high levels of polymorphisms in the present study compared with reports from Africa, India, and China. The molecular diversity estimated in our analysis, together with agronomical or morphological data, can be very useful for plant breeding programs, given the importance of Jatropha species in oil production. Interestingly, Central American Jatropha material can be used to increase the genetic base of J. curcas populations localized in Asia and Africa, where reduced genetic diversity has been reported.展开更多
Population density,species richness and critical population parameters are crucial in determining the levels of gene diversity in dioecious species of the genus Calamus.The extent of intraspecific and intrageneric gen...Population density,species richness and critical population parameters are crucial in determining the levels of gene diversity in dioecious species of the genus Calamus.The extent of intraspecific and intrageneric genetic variability in Calamus from the southern Western Ghats of India was studied using 26 microsatellite markers by sampling 227 individuals belonging to seven economically important species.The heterozygosity of microsatellite loci ranged from zero to 0.78.Average gene diversity within species was 0.13;in all species it was 0.18 and amongst species was 0.06.The Shannon Information Index was the lowest for Calamus metzianus(0.11),whereas it ranged from 0.16 to 0.26 for other species.The expected heterozygosity varied from 0.08 to 0.18.Calamus hookerianus and Calamu travancoricus showed the highest genetic differentiation(44%)revealed through Fst values,whereas the lowest(22%)was observed between Calamus gamblei and Calamu thwaitesii.Population structuring and phylogenetic analysis differentiated the seven species.Due to overexploitation and loss of rare alleles,small populations could lead to fertilization between closely related individuals,resulting in inbreeding and increasing the risk of extinction.This could be important for species such as C.metzianus where allelic polymorphism was 23%,whereas for all other species it was 38%to 46%.Genetic diversity“micro-hotspots”were identified from the protected area network of the southern and central Western Ghats with highest observed heterozygosity.Four microhotspots from the Agasthyamalai Biosphere Reserve and the Pushpagiri Wildlife Sanctuary may be possible for long-term conservation programs.The findings of this study lay a strong foundation for strengthening protected area networks,especially areas with intermediate levels of disturbance.展开更多
We assessed chemical composition and variation in oil content and seed weight of 40 wild-growing almonds（Prunus L. spp.） accessions collected from different parts of Iran. There were significant differences in kerne...We assessed chemical composition and variation in oil content and seed weight of 40 wild-growing almonds（Prunus L. spp.） accessions collected from different parts of Iran. There were significant differences in kernel weight and oil parameters. Accessions ranged from0.20 to 1.5 g in kernel weight, 0.2–3.0 mm in shell thickness, and 16–55 % in oil content. The predominant vegetable oil components of kernels were 4.6–9.5 % palmitic acid, 0.4–0.8 % palmitoleic acid, 1.0–3.4 % stearic acid,48.8–88.4 % oleic acid and 11.3–33.2 % linoleic acid.Linolenic acid was detected in 15 accessions. High heritability was recorded for all studied traits and was maximum for shell thickness（98.5 %） and minimum for oil content（97.1 %）. Maximum and minimum ‘Euclidean＇pair wise dissimilarities were 17.9 and 0.5, respectively.All 40 accessions were grouped into two major clusters.展开更多
文摘Jute mallow is a nutritious leafy vegetable. The leaves are rich in proteins, vitamins and essential amino acids. Molecular characterization of Jute mallow with focus on improvement of leaf yield is scarcely reported. In the present study, inter sequence simple repeats (ISSR) molecular markers were employed to assess genetic diversity and relationships of 83 accessions of Jute mallow from different parts of Africa and Asia conserved at the World Vegetable Center East and Southern Africa. A total of 89 bands were amplified by 8 ISSR primers. Number of polymorphic bands per primer ranged from 2 to 6 with an average of 2.75 bands per primer. Polymorphic information content (PIC) values ranged from 0.390 to 0.760 with average of 0.53. Average Nei’s gene diversity (h) and Shannon’s information index (I) were 0.335 and 0.494 respectively. The highest pairwise genetic distance was 0.431 observed in a population from East Africa accessions. PC1 and PC2 axis explained 21.69% and 11.66% of the total variation respectively. UPGMA cluster analysis grouped the accessions into six main clusters at genetic similarity coefficient of 0.53 as standard value for classification. These results have important implications for jute mallow breeding and conservation.
基金supported by the National Natural Science Foundation of China (31660215)Major Scientific and Technological Projects of Guizhou Province ([2018]5261),China+1 种基金the Construction Project for First-Class Ecology Discipline in Guizhou (GNYL [2017] 007),Chinathe China Scholarship Council ([2021]15)
文摘Larix resources in the Qinghai-Tibet Plateau have important ecological and economic values.However,the lack of genetic diversity background and related research hinders the development of conservation strategies.In this study,genetic diversity and distribution of fi ve Larix species were investigated.Using 19 polymorphic microsatellite markers to study 272 representative individuals from 13 populations,the results show low genetic diversity at the population level,with variation explained mainly by diff erentiation among populations.The Larix populations were classifi ed into two clades,one formed by eight populations,including three of the species in this study,L.kongboensis,L.speciosa,and L.potaninii var.australis.The other clade consists of fi ve populations,including the other two species in this study,L.griffi thii and L.himalaica.Genetic distance of the species was aff ected by geographical isolation and genetic diversity was mainly aff ected by altitude.The area suitable for Larix spp.decreased during the Last Glacial Maximum compared to the current distribution according to the niche model,but should increase in future climate scenarios(2050s),expanding westward along the Himalayas.These results provide an important scientifi c basis for the development of conservation strategies and further the sustainable utilization of Larix resources in the Qinghai-Tibet Plateau.
基金supported by the National Key Technology Research and Development Program of China(2011BAZ01732)the Project of the Ministry of Agriculture of China(CARS-25)+2 种基金the Core Research Budget of the Non-profit Governmental Research Institute,China(ICS,CAAS1610032011011)the Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP-IVFCAAS)
文摘Pepper（Capsicum spp.） is an important vegetable crop in the world. Now the pepper in China contributes one-third of the world＇s peppers production. Genetic diversity of the pepper germplasm of China is expected interesting to know. To explore the structure of genetic diversity in Chinese pepper germplasm resources and possible relationship with cultivar types or geographic origin, we sampled and compared 372 Gen Bank pepper accessions（local cultivars and landraces） from 31 provinces, autonomous regions and municipalities of China and 31 additional accessions from other countries. These accessions were genotyped using 28 simple sequence repeat（SSR） markers spanning the entire pepper genome. We then investigated the genetic structure of the sampled collection using model-based analysis in STRUCTURE v2.3.4 and examined genetic relationships by the unweighted pair-group method of mathematical averages（UPGMA） in MEGA. In addition to geographic origin, we evaluated eight plant and fruit traits. In total, 363 alleles were amplified using the 28 SSR primers. Gene diversity, polymorphism information content and heterozygosity of the 28 SSR loci were estimated as 0.09–0.92, 0.08–0.92 and 0.01–0.34, respectively. The UPGMA cluster analysis clearly distinguished Capsicum annuum L. from other cultivated pepper species. Population structure analysis of the 368 C. annuum accessions uncovered three genetic groups which also corresponded to distinct cultivar types with respect to the plant and fruit descriptors. The genetic structure was also related to the geographic origin of the landraces. Overall results indicate that genetic diversity of Chinese pepper landraces were structured by migration of genotypes followed by human selection for cultivar types in agreement with consumption modes and adaptation to the highly diversified agro-climatic conditions.
基金This work was supported by the Vicerrectoría de Investigación of the University of Costa Rica and the National Center for Biotechnological Innovations—CENIBiot,through the project No.111-B2-503 and CB-D1-2010 respectively.
文摘The genetic diversity from species of the genus Jatropha collected from Costa Rica was analyzed by AFLP (amplified fragments length polymorphism). The study consisted of 114 accessions from 15 populations of 4 different species: J. curcas, J. costaricensis, J. gossypifolia and J. stevensii. These were collected from different locations in Costa Rica. Three different primers were used, resulting in 428 loci, and they were classified in three categories: unique and double bands (UBD), rare bands (RB) and shared bands (SB). The UBD were excluded for a total of 339 polymorphic loci used for the UPGMA dendrogram and principal component analysis (PCA). The species that obtained the highest average of polymorphic loci was J. curcas, which obtained the highest percentage of polymorphic loci (80.24%), followed by J. gossypifolia (79.35%), J. costaricensis (78.76%), and finally J. stevensii (40.71%). The average for the polymorphic loci was of 69.76%. Thus, the phylogeny of the Jatropha species in Costa Rica was elucidated, showing J. curcas more related to J. stevensii and this one with J. costaricensis, and J. gossypifolia as the most distant member of the genus. For the best of our knowledge this is the first report of a genetic analysis of J. costaricensis and J. stevensii. The obtained molecular evidence showed high levels of polymorphisms in the present study compared with reports from Africa, India, and China. The molecular diversity estimated in our analysis, together with agronomical or morphological data, can be very useful for plant breeding programs, given the importance of Jatropha species in oil production. Interestingly, Central American Jatropha material can be used to increase the genetic base of J. curcas populations localized in Asia and Africa, where reduced genetic diversity has been reported.
基金The work was supported by the Department of Biotechnology,Government of India(Order No.BT/156/NE/TBP/2011)the Kerala State Council for Science,Technology and Environment(KSCSTE),Thiruvananthapuram(Order No.234/KBC/2012/KSCSTE).
文摘Population density,species richness and critical population parameters are crucial in determining the levels of gene diversity in dioecious species of the genus Calamus.The extent of intraspecific and intrageneric genetic variability in Calamus from the southern Western Ghats of India was studied using 26 microsatellite markers by sampling 227 individuals belonging to seven economically important species.The heterozygosity of microsatellite loci ranged from zero to 0.78.Average gene diversity within species was 0.13;in all species it was 0.18 and amongst species was 0.06.The Shannon Information Index was the lowest for Calamus metzianus(0.11),whereas it ranged from 0.16 to 0.26 for other species.The expected heterozygosity varied from 0.08 to 0.18.Calamus hookerianus and Calamu travancoricus showed the highest genetic differentiation(44%)revealed through Fst values,whereas the lowest(22%)was observed between Calamus gamblei and Calamu thwaitesii.Population structuring and phylogenetic analysis differentiated the seven species.Due to overexploitation and loss of rare alleles,small populations could lead to fertilization between closely related individuals,resulting in inbreeding and increasing the risk of extinction.This could be important for species such as C.metzianus where allelic polymorphism was 23%,whereas for all other species it was 38%to 46%.Genetic diversity“micro-hotspots”were identified from the protected area network of the southern and central Western Ghats with highest observed heterozygosity.Four microhotspots from the Agasthyamalai Biosphere Reserve and the Pushpagiri Wildlife Sanctuary may be possible for long-term conservation programs.The findings of this study lay a strong foundation for strengthening protected area networks,especially areas with intermediate levels of disturbance.
基金financially supported by Payam-e-Noor University
文摘We assessed chemical composition and variation in oil content and seed weight of 40 wild-growing almonds（Prunus L. spp.） accessions collected from different parts of Iran. There were significant differences in kernel weight and oil parameters. Accessions ranged from0.20 to 1.5 g in kernel weight, 0.2–3.0 mm in shell thickness, and 16–55 % in oil content. The predominant vegetable oil components of kernels were 4.6–9.5 % palmitic acid, 0.4–0.8 % palmitoleic acid, 1.0–3.4 % stearic acid,48.8–88.4 % oleic acid and 11.3–33.2 % linoleic acid.Linolenic acid was detected in 15 accessions. High heritability was recorded for all studied traits and was maximum for shell thickness（98.5 %） and minimum for oil content（97.1 %）. Maximum and minimum ‘Euclidean＇pair wise dissimilarities were 17.9 and 0.5, respectively.All 40 accessions were grouped into two major clusters.
