Drought Effects on Soybean Cultivation - A Review

The soybean crop is exposed to many adverse environmental conditions; among them, it is the drought stress, which is responsible for great losses on crop yield. The crops productivity improvement may have a limit due stress factors, as noted by its stabilization in the past years in 80% of their theoretical yield potential. These stress factors may be biotic or abiotic, affecting the plants growth and development. Among the abiotic factors, the drought is considered the most devastating, affecting all plants growth and development stages causing huge losses in soybean yield. In the field, such stresses occur simultaneously, limiting the plants growth and development, compromising sustainable agriculture. This review article focused on Drought effects on soybean cultivation. Field studies that indicate the performance of cultivars in different drought patterns are necessary to identify the genotypes response mechanisms. Recent studies in southern Brazil on drought response soybean were generated under greenhouse conditions and fields showing that plants can modulate the metabolism in response to this adverse drought circumstance by targeting different mechanisms, aiming to survival and keep productivity. Studies have shown that cultivars with lower daily water use before flowering, but higher use after flowering had higher grain yield and higher water use efficiency. In the future, since the drought events tend to become more severe and frequent in Brazil and worldwide, the study and obtainment of drought resistant cultivars is necessary.