Soybean Plants Under Waterlogging Stress: Responses and Adaptation Mechanisms

Waterlogging stress retards plant growth and development by inducing a number of physiochemical processes. Plants subjected to waterlogging suffer from substantial yield losses. In soybean, waterlogging stress creates partial or full deprivation of oxygen, which leads to severe morphophysiological decays in the plant. Excess accumulation of reactive oxygen species and poor antioxidant defense system become phenomenal under such conditions. As a consequence, water and nutrient uptake, stomatal conductance, photosynthesis rate, enzymatic activities, and hormonal balances are greatly disrupted. However, soybean develops few anatomical features among which the formation of the adventitious root is of great importance to counteract the detrimental effect of waterlogging stress. This chapter focuses on soybean plant responses to waterlogging conditions and different approaches how waterlogging tolerance or adaptation can be imparted in soybean through morphological and anatomical modifications as well as hormonal regulation and antioxidant balance.