QTL detection for flowering time in faba bean and the responses to ambient temperature and photoperiod

Abstract

Faba bean (Vicia faba L.) is a grain legume primarily used for animal feed and human food grown in a range of environments, globally. Time of flowering in faba bean is critical for adaptation to specific environments and is controlled largely by factors such as ambient temperature and photoperiod. The aim of this study was to investigate the genetic control of flowering time and the responses of flowering time to ambient temperature and photoperiod in faba bean. A bi-parental recombinant inbred line population (Icarus 9 Ascot) was evaluated over three years in field trials and three different controlled environments with varying temperatures and photoperiods. QTL analysis identified eight regions of co-localised QTLs associated with days to flowering, thermal time to flowering and node of first flower; on Chr-I.A/III/V, Chr-I.B.3, Chr-III.1, Chr-III.2, Chr-V.1 and Chr-V.2. Two of the detected regions are common with previously detected QTLs, up to two more are possibly common and the remaining four appear to be novel. For the first time, the associations of these QTLs with ambient temperature and photoperiod response were described. Candidate genes for some of the QTLs were identified using the associations with ambient temperature and photoperiod response together with knowledge extended from other legumes that have a syntenic relationship with faba bean.