Detecting QTLs for plant architecture traits in cucumber (Cucumis sativus L.)

Abstract

To improve the efficiency of breeding cucumber in China, we previously mapped QTL for most fruit- and flower-related traits of this species. Here, we mapped QTLs for six plant architecture traits including lateral branch number (LBN), lateral branch total length (LBTL), main-stem length (MSL), internode length (INL), main-stem diameter (MSD), and petiole length (PL) were detected in greenhouse environments. In total, 14 QTLs were identified for the six traits (LBN, 3; LBTL, 2; MSL, 3; INL, 2; MSD, 2; and PL, 2) with additive heritability of individual QTL ranging from 1.6% to 29.5%. Five QTLs for four traits (LBN, LBTL, MSL, and INL) were observed to have significant (P ≤ 0.05) QTL x environment interaction effects. The broadsense heritability for the six traits ranged from 8.5% to 47.0%. The QTL information presented in this research, together with the data in our previous study on the fruit- and flower-related traits, will facilitate the breeding of elite cucumber cultivars by marker-assisted selection in China.