Abstract
Oilseed rape (Brassica napus L.) is one of the most important oil crops in China as well as worldwide. Branch angle as a plant architecture component trait plays an important role for high density planting and yield performance. In this study, bulked segregant analysis (BSA) combined with next generation sequencing technology was used to fine map QTL for branch angle. A major QTL, designated as branch angle 1 (ba1) was identified on A06 and further validated by Indel marker-based classical QTL mapping in an F2 population. Eighty-two genes were identified in the ba1 region. Among these genes, BnaA0639380D is a homolog of AtYUCCA6. Sequence comparison of BnaA0639380D from small- and big-branch angle oilseed rape lines identified six SNPs and four amino acid variation in the promoter and coding region, respectively. The expression level of BnaA0639380D is significantly higher in the small branch angle line Purler than in the big branch angle line Huyou19, suggesting that the genomic mutations may result in reduced activity of BnaA0639380D in Huyou19. Phytohormone determination showed that the IAA content in Purler was also obviously increased. Taken together, our results suggested BnaA0639380D is a possible candidate gene for branch angle in oilseed rape.
Highlights
Rapeseed is one of the most important oil crops worldwide and yield enhancement is very important for achieving high production profit
Taken the advantage of conventional quantitative trait locus (QTL) analysis, expression pattern and phytohormones determination, we provided evidence that one gene which is the homolog of AtYUCC6 encoding flavin monooxygenase, located at chromosome A06 is a candidate gene for branch angle in B. napus
Since the first article published in yeast[36], many QTL or candidate genes have been identified in different plant species by QTL-seq[38,39,40,41,42,43,44]
Summary
Rapeseed is one of the most important oil crops worldwide and yield enhancement is very important for achieving high production profit. Among all the agronomic traits under domestication process, plant architecture, e.g. leaf angle or branch angle, has played an important role in the adaption to high-density planting at present[4]. Branch angle is one of the most important traits of plant architecture, as it determines the optimum planting density and influences yield through affecting photosynthesis efficiency[8]. Erect leaf trait can enhance photosynthetic efficiency and allow for increased planting density, leading to higher grain yield in maize[10]. Loose Plant Architecture[1] (LPA1) regulates both tiller angle and leaf angle in rice by controlling the adaxial growth of tiller node and lamina joint[17]. Similar to AtYUCCA6, other YUCCA orthologous involved in auxin synthesis may play a role in the regulation of branch angle
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
