Seed vigour-related DNA marker in rice shows homology with acetyl CoA carboxylase gene

Abstract

Germination potential, i.e. vigour manifested at sensu stricto germination, was studied in 22 rice varieties to distinguish between the genetic control for low vigour (lv) at fresh harvest and lv after ageing of seeds. For identifying seed vigour-associated DNA marker(s), correlative studies between (1) physiological parameters viz. germination of (a) unaged seeds under optimum and cold stressed condition, (b) aged seeds under optimal condition and (2) growth-associated biochemical parameters viz. alcohol dehydrogenase (ADH) and esterase (EST) activity during early germination of fresh seeds and antioxidant potential in dry embryos of fresh and aged (1 year) seeds were undertaken. ADH and EST activity as well as antioxidant potential showed positive correlation with speed of embryo emergence and early seedling growth of seeds. The reduction of antioxidant potential in aged seeds also appeared proportional to germination performance. Random amplified polymorphic DNA analysis between the varieties was correlated with the above-mentioned vigour parameters, using multiple regression analysis. This led to the identification of four bands associated with the vigour trait at 99% significance level; of these, the ~ 900-bp DNA fragment (named as HVAC 19), through basic local alignment search tool nucleotides analysis, revealed a sequence homology with acetyl CoA carboxylase (ACCase) gene of wheat at 94% similarity level.