Impact of Extreme Temperature and Soil Water Stress on the Growth and Yield of Soybean (Glycine max (L.) Merrill)
Date
2022
Journal Title
Journal ISSN
Volume Title
Publisher
MDPI
Abstract
Climate change is a major environmental stressor that would adversely affect tropical
agriculture, which is largely rain-fed. Associated with climate change is an increasing trend in
temperature and decline in rainfall, leading to prolonged and repeated droughts. The purpose of this
study was to determine the effect of climate variables such as temperature, relative humidity, vapor
pressure deficit (VPD), and soil water on the phenology, biomass, and grain yield of soybean crops.
A greenhouse experiment was set in a split plot design with three average environmental conditions
as the main plots: E1 (36 ◦C, RH = 55%), E2 (34 ◦C, RH = 57%) and E3 (33 ◦C, RH = 44%). Additionally,
there were three water treatments: W1 (near saturation), W2 (Field capacity), and W3 (soil water
deficit) and two soybean varieties (Afayak and Jenguma). These treatments were replicated nine
times. The results showed that high temperatures (E1) accelerated the crop development, particularly
at flowering. Additionally, increased atmospheric demand for water under a high temperature
environment resulted in high evapotranspiration, leading to high transpiration which probably
reduced photosynthetic activity of the plants and thereby contributing to biomass and grain yield
loss. Biomass and yield were drastically reduced for the combined effect of high temperature (E1)
and drought (W3) as compared to combined effect of ambient temperature (E3) and well-watered
condition (W1). Increasing temperatures and erratic rainfall distributions associated with climate
change poses a potential threat to the soybean production in Ghana.
Description
Research Article
Keywords
drought, smallholders, climate change, soybean, Ghana