Evaluation of morpho-physiological characters of gamma rays-irradiated soybean mutant lines under shade stress environment

Abstract

Soybean, being one of the primary food sources for the Indonesian population, currently faces insufficient production from domestic harvests. Intercropping cultivation technique offers a potential solution to increase soybean production by expanding planting area, such as the area under plantation stands. However, low productivity persists due to shade stress. This study aims to evaluate the morpho-physiological characters of soybean genotypes under shading stress. The genetic materials used were 13 genotypes consisting of 10 promising mutant lines, resulted from mutant induction and selection from soybean variety Mutiara 1, and 3 check varieties, namely Dena 1, Dena 2, and Mutiara 1. This study employed a split plot arrangement, with shading treatment as the whole plot and soybean genotypes as subplots. ANOVA tests and stress tolerance index analyses revealed a significant increase in plant height and stomatal conductivity among soybean genotypes under shading environments. Conversely, shading treatments exhibited a significant impact on reducing plant branching and leaf chlorophyll content.