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International audience; 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 579bp sequence deletion in its 5 0 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.

Pepper (Capsicum spp.) is one of the earliest domesticated crops, providing a unique pungent sensation when eaten. Through the construction of the first pepper variome, we describe the main groups that emerged during domestication and breeding of C. annuum, their relations and temporal succession, and the molecular events underlying the main transitions. The initial differentiation in fruit shape and pungency, increase in fruit weight, and transition from erect to pendent fruits, and the recent appearance of blocky, large, sweet fruits (bell peppers), were accompanied by strong selection/fixation of key alleles and introgressions in two large genomic regions. Furthermore, we describe the identification of Up, a key domestication gene controlling erect vs pendent fruit orientation, encoding a BIG GRAIN protein involved in auxin transport, and Flip1 associated with capsaicinoid content, encoding a protein involved in phospholipid flipping. The function of Up was confirmed by virus-induced gene silencing. These findings constitute a cornerstone for understanding the domestication and differentiation of a key horticultural crop.

Fertility restoration of cytoplasmic male sterility (CMS) in Capsicum annuum is controlled by multiple alleles of Restorer-of-fertility (Rf) genes. The isolation of additional Rf genes should therefore enrich the knowledge of CMS/Rf systems and accelerate their exploitation in hybrid seed production. In this study, the fertility restorer gene CaRfm of ‘0601 M’, a non-pungent bell pepper, was genetically mapped to a 1.2-cM region flanked by KASP markers S761 and S183. CaRfm was then physically mapped to a 128.96-Kb interval predicted from 24 recombinants with two co-segregated markers, S423 and S424. CaPPR6 encoding a pentatricopeptide repeat (PPR) protein was suggested as the most likely candidate gene for the CaRfm locus on the basis of sequence alignment as well as genotyping of tightly linked markers. In addition, molecular markers S1597 and S1609, which are immediately adjacent to CaRfm at 15.7 and 57.8-Kb respectively, were developed and applied to marker-assisted selection. The results provided friendly markers for breeding pepper restorer lines and laid the foundation for elucidating the male fertility restoration mechanism. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12298-021-01109-9.

Broccoli is a worldwide vegetable famous for good nutrition that is particularly rich in sulforaphane. The evolution of 95 broccoli cultivars that were widely collected and cultivated in China since 1980 was evaluated using 35 pairs of SSR markers. Thirty-five markers were selected from 960 pairs of SSR markers designed from Brassica oleracea, rapa and napus by two resources with different maturity periods. The results revealed that all 35 pairs of SSR markers were polymorphic, and 167 alleles were amplified with an average of 4.8 per marker. The mean content was 0.79 for polymorphism information, with a range from 0.48 to 0.99. The genetic diversity indexes ranged from 0.6909 to 0.8969, with an average of 0.7809. Genetic diversity analysis indicated the 95 genotypes could be separated into five primary sub-groups at a 0.72 distance. Sub-group A included more than 70% of genotypes with early and mid-early maturating cultivars, and the cultivars covered more than 87% of the genotypes of the 95 materials, including the primary cultivars widely planted that directed the domestication of broccoli in China in the past 37 years. Sub-groups B and C contained one inbred line with high generation and one DH line, respectively, suggesting both were innovative resources in cultivation. Sub-groups D and E were all inbred lines, and sub-group D had six members with similar characteristics: small florets, high-domed head, tall plants with nearly no lateral branches and good heat tolerance. Sub-group E had five members that presented similar wrinkle leaf morphology, and most matured at an intermediate rate, except IVF-B18. In this study, the evolution of broccoli cultivars in China was first summarized overall, together with their characteristics and distributions in China. Our study provides important information on genetic diversity and for cultivar replacement of broccoli in China, in addition to two new germplasms and polymorphism markers for research and molecular breeding.