Investigation and Analysis on Agricultural Biological Resources of Wuchuan Gelao and Miao Autonomous County,Guizhou Province

Wuchuan Gelao and Miao Autonomous County is located in the northeast of Guizhou Province,and in the border of Guizhou and Chongqing,having a subtropical humid monsoon climate. There is no severe heat in summer,and no severe cold in winter. It has distinct national characteristics,and there are many biological resources with national characteristics. A systematic investigation of biological resources in the county for nearly a month was carried out by organizing a professional investigation team. The investigation covered 5 townships and we visited 12 village committees and 26 villagers' groups,involving three ethnic groups: Gelao,Tujia and Miao. The biological resources closely related to the agricultural production and life of local ethnic groups were investigated,collected and sorted out. A total of 230 samples of all kinds of resources were collected,including 47 food crops,75 vegetables and annual crops,37 fruit trees and perennial crops,and 71 medicinal plants. Of these,a total of 73 were unique,superior and special resources. Based on general investigation and professional investigation,this paper analyzes the present situation,growth and decline of local agricultural biological resources,and puts forward some suggestions for the protection,development and utilization of agricultural biological resources.

Investigation and Analysis of Nutrition Components of Wild Chives Collected from Hezhang County of Guizhou Province

Guizhou Province is an important distribution area of wild onion resources,and a large area of wild( Chinese) chives are distributed in Hezhang County. In order to understand and study the distribution of wild chives,the geographical distribution,habitats and climate of wild chives in Hezhang County were investigated,and the main nutrition components of wild chives were analyzed. The results indicated that there were mainly three kinds of wild chives distributed in Hezhang County, including Allium wallichii Kunth., Allium ovalifolium Hand.-Mazz.( tentatively named),and Allium hookeri Thwaites( tentatively named). Among the 17 kinds of amino acids,except for proline,the content of other amino acids in wild chives was higher than that of the cultivated chives( Allaum tuberosum Rottler ex Spreng.). The sugar content of wild chives was significantly lower than the cultivated chives. Among nine trace elements,the manganese,zinc and iron content of A. ovalifolium Hand.-Mazz. were significantly higher than that of the cultivated chives and other wild chives. Among the four kinds of heavy metals,cadmium content in the three kinds of wild chives exceeded the limitation of the national standard,and cadmium content in A. ovalifolium Hand.-Mazz. was significantly higher than that of the others. Arsenic,mercury and lead content in A. ovalifolium Hand.-Mazz. also exceeded the limitation of the national standard. Vitamin C content in leaves and stalk of A. wallichii Kunth. in the original habits was higher than that of the cultivated chives. The biological characteristics and nutrition components of the wild chives from Hezhang County were significantly different from that of the cultivated chives. The collection and preservation of these resources are of great significance to the enriching of diversity of Chinese chive resources and has great development and utilization value to the improvement of nutritional quality of Chinese chives.

Pan-genome of Raphanus highlights genetic variation and introgression among domesticated,wild,and weedy radishes

Post-polyploid diploidization associated with descending dysploidy and interspecific introgression drives plant genome evolution by unclear mechanisms.Raphanus is an economically and ecologically important Brassiceae genus and model system for studying post-polyploidization genome evolution and introgres-sion.Here,we report the de novo sequence assemblies for 11 genomes covering most of the typical sub-species and varieties of domesticated,wild and weedy radishes from East Asia,South Asia,Europe,and America.Divergence among the species,sub-species,and South/East Asian types coincided with Quaternary glaciations.A genus-level pan-genome was constructed with family-based,locus-based,and graph-based methods,and whole-genome comparisons revealed genetic variations ranging from single-nucleotide polymorphisms(SNPs)to inversions and translocations of whole ancestral karyotype(AK)blocks.Extensive gene flow occurred between wild,weedy,and domesticated radishes.High fre-quencies of genome reshuffling,biased retention,and large-fragment translocation have shaped the genomic diversity.Most variety-specific gene-rich blocks showed large structural variations.Extensive translocation and tandem duplication of dispensable genes were revealed in two large rearrangement-rich islands.Disease resistance genes mostly resided on specific and dispensable loci.Variations causing the loss of function of enzymes modulating gibberellin deactivation were identified and could play an important role in phenotype divergence and adaptive evolution.This study provides new insights into the genomic evolution underlying post-polyploid diploidization and lays the foundation for genetic improve-ment of radish crops,biological control of weeds,and protection of wild species'germplasms.

Pepper variome reveals the history and key loci associated with fruit domestication and diversification

Pepper(Capsicum spp.)is an important vegetable crop that provides a unique pungent sensation when eaten.Through construction of a pepper variome map,we examined the main groups that emerged during domestication and breeding of C.annuum,their relationships and temporal succession,and the molecular events underlying the main transitions.The results showed that the initial differentiation in fruit shape and pungency,increase in fruit weight,and transition from erect to pendent fruits,as well as the recent appearance of large,blocky,sweet fruits(bell peppers),were accompanied by strong selection/fixation of key alleles and introgressions in two large genomic regions.Furthermore,we identified Up,which encodes a BIG GRAIN protein involved in auxin transport,as a key domestication gene that controls erect vs pendent fruit orientation.The up mutation gained increased expression especially in the fruit pedicel through a 579-bp sequence deletion in its 5′upstream region,resulting in the phenotype of pendent fruit.The function of Up was confirmed by virus-induced gene silencing.Taken together,these findings constitute a cornerstone for understanding the domestication and differentiation of a key horticultural crop.