Lima M F, Carvalho S I C, Ragassi C F, Bianchetti L B, Faleiro F G, Reifschneider F J B
Embrapa Hortaliças, , Brasil
Embrapa Hortaliças, , Brasil.
Genet Mol Res. 2017 Aug 31;16(3):gmr-16-03-gmr.16039704. doi: 10.4238/gmr16039704.
Germplasm banks are essential as sources of genetic variability for plant breeding programs. To characterize a Brazilian Capsicum frutescens collection, 21 malagueta and 5 Tabasco hot pepper accessions were evaluated under field and greenhouse conditions regarding morphological and molecular traits, as well as resistance to viruses. Morphological characterization was performed using 53 IPGRI (International Plant Genetic Resources Institute) descriptors, 15 vegetative, 13 inflorescence, 22 fruit, and 3 seed. Molecular characterization was carried out with 60 polymorphic markers from 29 RAPD primers. The incidence of major viruses infecting Capsicum spp, Tomato spotted wilt virus (TSWV), Groundnut ringspot virus (GRSV), Potato virus Y (PVY), Pepper yellow mosaic virus (PepYMV), Pepper mild mottle virus (PMMoV), and Cucumber mosaic virus (CMV) was evaluated by ELISA. Based on the average genetic distance among genotypes, six groups were defined for the 53 IPGRI descriptors. When considering only 11 quantitative traits (five vegetative and six fruit), six groups were also determined, and the traits plant canopy width (56.05%) and days to fruiting (25.07%) most explained the genetic diversity among genotypes. Molecular analysis defined five groups of accessions with partial correspondence to the morphological characterization data. The incidence of viruses in field-grown plants varied among genotypes and according to virus species, from 5.6% (GRSV; CNPH 3286) to 100% (PMMoV; CNPH2871), and indicated some accessions as potential sources of virus resistance. These results demonstrate the genetic variability within the group of 26 hot pepper accessions, as well as virus-resistant genotypes that can be used in breeding programs.
种质库作为植物育种计划中遗传变异的来源至关重要。为了对巴西辣椒品种进行特征描述，在田间和温室条件下，对21份马拉盖塔辣椒和5份塔巴斯科辣椒种质进行了形态、分子性状以及病毒抗性评估。使用53个国际植物遗传资源研究所（IPGRI）的描述符进行形态特征描述，其中15个为营养性状、13个为花序性状、22个为果实性状、3个为种子性状。利用29个随机扩增多态性DNA（RAPD）引物中的60个多态性标记进行分子特征分析。通过酶联免疫吸附测定（ELISA）评估感染辣椒属植物的主要病毒，即番茄斑萎病毒（TSWV）、花生环斑病毒（GRSV）、马铃薯Y病毒（PVY）、辣椒黄花叶病毒（PepYMV）、辣椒轻斑驳病毒（PMMoV）和黄瓜花叶病毒（CMV）的发生率。基于基因型之间的平均遗传距离，对53个IPGRI描述符定义了六组。仅考虑11个数量性状（5个营养性状和6个果实性状）时，也确定了六组，其中植株冠幅（56.05%）和结果天数（25.07%）这两个性状最能解释基因型之间的遗传多样性。分子分析定义了五组种质，与形态特征数据部分对应。田间种植植物中病毒的发生率因基因型和病毒种类而异，从5.6%（GRSV；CNPH 3286）到100%（PMMoV；CNPH2871），并表明一些种质是潜在的病毒抗性来源。这些结果证明了26份辣椒种质群体内的遗传变异，以及可用于育种计划的抗病毒基因型。
