Effect of normal irrigation and water stress conditions on some characteristics of cotton in Toshka region -Egypt

Irrigation, water stress, planting dates and planting distances are crucial for obtaining desirable fiber properties for Egyptian cotton, especially under climate change. Two field experiments were carried out at the Water Studies and Research Complex (WSRC) station, National Water Research Center, Toshka, Egypt in the 2021 and 2022 growing seasons, to evaluate some morphological traits and fiber quality properties of the Egyptian cotton cultivar Giza 95 under three planting dates (january, february, and march) and 6 planting distances (10, 15, 20, 25, 30, and 35 cm among plants), comparing them with two irrigation treatments (100% A.W. and 80 % A.W.). The main effects of irrigation treatments, planting dates, and planting distances in both seasons were found to be significant (P<0.05 or 0.01) for most morphological and fiber quality properties under study. Also, the first-order interactions of irrigation treatments with planting dates, and planting distances have significant effects (P<0.05 or 0.01) on most studied traits in both seasons. In both seasons, positive effects were observed for the number of fruiting branches, plant height, and fiber fineness traits with irrigation treatment (80 % A.W.) and other fiber quality properties with irrigation treatment (100% A.W.). When compared to other planting dates in both seasons, the February planting date produced the best values for the majority of the analyzed traits, however, the January planting date produced a higher number of fruiting branches. Wider plant spacing produced the best results for fiber quality properties, whereas 10 cm spacing between plants resulted in more fruiting branches. Based on mean performances and principle component analysis, the February planting date with wider plant spacing under irrigation treatment (80% A.W) may be a better method to improve fiber quality properties in the experimental region under study. Additionally, these data will help develop plans for better agricultural practices and enhancing Egyptian cotton's fiber quality