Gas exchanges and soybean plant production in response to waterlogged soil and light restriction

Abstract

Soybean plants grown in waterlogged soil and a low-light environment show losses in growth and production. Thus, the objective of this study was to investigate the chlorophyll content, foliar nutrient content, gas exchanges, dry matter accumulation and the production of soybean plants submitted to waterlogged soil and light restriction. The first factor was the presence and absence of waterlogged soil; the second was the presence and absence of light restriction. For the treatments with waterlogged soil, it was kept above the field capacity. For the imposition of the light restriction, a shading screen, with the capacity to retain 80% of the incident light, was used. The treatments impositions occurred simultaneously, starting at full bloom (R₂), lasting for 30 days until the beginning seed (R_5.2). Plants submitted to waterlogged soil and light restriction showed a reduction on the liquid photosynthetic rate, transpiration, and stomatal conductance. Plants conducted in waterlogged soil in full sun showed chlorotic leaves with reduced levels of foliar nutrients and dry matter accumulation. Thus, the waterlogged soil and/or light restriction, for a 30-day period, from R₂, negatively affect the photosynthesis, the dry matter accumulation and causes less soybean production.