Physiology of seed yield in soybean: Growth and dry matter production

Abstract

A field study was conducted to assess the growth parameters controlling the dry matter and seed yield of soybean. The result shows that growth rate was slow during vegetative phase in all genotypes. A relatively smaller portion of total dry mass (TDM) was produced before flower initiation and the bulk of it after anthesis. Maximum absolute growth rate (AGR) was observed during pod filling stage in all genotypes due to maximum leaf area (LA) development and leaf area index (LAI) at this stage. Plant characters like LAI and AGR contributed to higher TDM production. Results indicate that a high yielding soybean genotype should possess larger LAI, higher TDM production ability and higher AGR at all growth stages.

Keywords: Soybean seed yield, total dry mass (TDM), leaf area index (LAI), absolute growth rate (AGR), relative growth rate (RGR)