Evaluation of Water Stress Tolerance of Soybean Using Physiological Parameters and Retrotransposon-Based Markers

Drought is one of the most important environmental stresses that severely reduce plant growth and crop productivity. This study was carried out to investigate the difference in the response of six soybean cultivars (Giza 21, 22, 35, 82, 83 and 111) under water stress and the genetic difference between these cultivars using retroelements technique. The results showed that drought stress caused reduction in morphological criteria, photosynthetic pigments, starch, phospholipids, glycolipids, pectin, cellulose and lignin in shoots of all soybean cultivars except Giza 22 and Giza 83. On the other hand, there was a considerable increase in root length, soluble sugars, proline, glycine betaine, total lipids and hemicellulose contents in the shoots of the soybean cultivars in response to water stress. The soybean cultivars Giza 22 and 83 were more drought tolerant than the other cultivars while Giza 21 and Giza 111 were the most sensitive. Inter-primer binding sites (iPBS) and inter-retrotransposon amplified polymorphism (IRAP) techniques were used to fingerprint the six soybean cultivars using a set of eight primers. The techniques successfully tagged each cultivar with specific bands and detected molecular genetic markers related to drought tolerance in soybean.