Prolonged waterlogging (WL) at different growth stages limits crops' ability to reach their full genetic potential. Few studies have examined the resilience of major crops to WL at the vegetative or reproductive stages. This study quantified the effects of short-term WL, recovery responses, and long-term impacts on yield and seed quality in three major crops (soybean, corn, and cotton). Five high-yielding cultivars or hybrids recommended for the Midsouth were evaluated for each crop under control (non-waterlogged) and WL conditions imposed for 7 days at the vegetative and reproductive stages. Short-term WL significantly affected gas exchange, photochemistry, pigments, biomass, and yield parameters across crops and growth stages ( p < 0.001 ). At the vegetative stage, stomatal conductance declined by 42–87 %, with partial recovery after 10 days. WL reduced ΦPSII, electron transport rate, and chlorophyll index (up to ∼98 % in corn) and increased flavonols in a crop- and stage-dependent manner. All three crops reduced biomass under WL, with the highest reductions in corn (66 %), followed by cotton (65 %), and soybean (55 %) during the vegetative stage. During the reproductive stage, biomass was reduced by 3 % in corn to 56 % in cotton. Soybean yield declined by an average of 52 % at both stages, while corn and cotton yields declined by 84 % under WL. Based on the stress tolerance index, relatively WL-tolerant soybean (P4604XFS, AG53XF2), corn (D56TC44), and cotton (DP2239B3XF, DP2317B3TF) were identified. These multi-crop, multi-stage field results demonstrated that 7 days of WL disproportionately affected genetic potential of crops, underscoring the importance of improving WL tolerance across growth stages. • Excessive rainfall and poor soil drainage during critical growth stages limit the genetic potential of crops. • Waterlogging at vegetative stages reduces growth; at reproductive stages, it impacts yield components. • Cotton was most sensitive, whereas corn and soybean showed intermediate tolerance. • High-yielding cultivars were sensitive to waterlogging at both vegetative and reproductive stages.
Adhikari et al. (Mon,) studied this question.