Short-day photoperiod effects on plant growth, flower bud differentiation, and yield formation in adzuki bean (Vigna angularis)

Abstract

Adzuki bean, a typical short-day plant (SDP) has high value of pharmaceutical and health care. This study investigated the SD photoperiod effects on plant morphological traits, physiological parameters, flower bud differentiation characterization and yield formation. For the purpose, a subset of SD photoperiod treatments was set up in a SD sensitive cultivar Tangshanhongxiaodou. The results indicated that the SD photoperiod affected largely the plant growth traits, decreased the duration from flowering to seed-filling stage which can modify the plant dry mass allocations. The SD photoperiod treatments increased the contents of chlorophyll and soluble protein at late growth stages, the net photosynthetic rate (Pn) and transpiration rate (Tr) also increased at the three growth stages. The GA1+3 content reduced and the ABA content increased under SD photoperiod treatments. Under SD photoperiod treatments, the flower bud differentiation processes were promoted. The SD photoperiod treatments reduced the yield components and yield, but not affected significantly the yield components and yield under SD-12 h treatment compared with SD-8 h treatment. Experimental results of present study conclude that SD- 12 h treatment can be shortened and without penalty on yield components and yield in North China and similar ecological region, which fit for breeding and cultivation technique practice improvement of adzuki bean.