Mapping of the Waxy Bloom Gene in ‘Black Jewel’ in a Parental Linkage Map of ‘Black Jewel’ × ‘Glen Ample’ (Rubus) Interspecific Population

Dora Pinczinger,Thomas Berner,Henryk Flachowsky,Jens Keilwagen,Marcel Von Reth,Andreas Peil,Ofere Francis Emeriewen

doi:10.3390/agronomy10101579

Abstract

Black and red raspberries (Rubus occidentalis L. and Rubus idaeus L.) are the prominent members of the genus Rubus (Rosaceae family). Breeding programs coupled with the low costs of high-throughput sequencing have led to a reservoir of data that have improved our understanding of various characteristics of Rubus and facilitated the mapping of different traits. Gene B controls the waxy bloom, a clearly visible epicuticular wax on canes. The potential effects of this trait on resistance/susceptibility to cane diseases in conjunction with other morphological factors are not fully studied. Previous studies suggested that gene H, which controls cane pubescence, is closely associated with gene B. Here, we used tunable genotyping-by-sequencing technology to identify the de novo SNPs of R. occidentalis and R. idaeus using an interspecific population that segregates for the waxy bloom phenotype. We created linkage maps of both species and mapped the identified SNPs to the seven chromosomes (Ro01–Ro07) of Rubus. Importantly, we report, for the first time, the mapping of gene B to chromosome 2 of R. occidentalis using a genetic map consisting of 443 markers spanning 479.76 cM. We observed the poor transferability of R. idaeus SSRs to R. occidentalis and discrepancies in their previously reported chromosome locations.

Highlights

Rubus, with approximately 750 species, is one of the genera of the Rosaceae family of plants with domesticated subgenera comprising of raspberries and blackberries [1]
R. idaeus SSRs in ‘Black Jewel’ (R. occidentalis) observed in our study is a microcosm of the results in Bushakra et al [11], we have focused on only Linkage Group 2 (LG2) SSRs following the preliminary mapping results, which indicated that gene B maps at LG2 of ‘Black Jewel’
An interspecific progeny derived from R. occidentalis and R. idaeus that segregates 1:1 for waxy bloom was the basis of this study

Summary

Introduction

With approximately 750 species, is one of the genera of the Rosaceae family of plants with domesticated subgenera comprising of raspberries and blackberries [1]. Strigosus (Michx.) Focke), and the black raspberry (R. occidentalis L.) are the most popular raspberries in this subgenus (Idaeobatus) and are diploid species with 2n = 2× = 14 chromosomes. Other members of the domesticated subgenera include flowering raspberries, blackberries, and arctic fruits [1]. Red and black raspberries are cross compatible and produce hybrid purple raspberries [2]. The canes of Rubus species are the shoots, which are perennials due to their biennial growth habit. Summer raspberries (floricanes) bear fruit in the second year on two-year-old canes; primocane raspberries bear fruit in the autumn of the first year on current-year shoots

Results

Discussion

Conclusion