Effect of 1-MCP On Plant Physiology and Yield of Cotton Plants Under Abiotic

Many environmental stress factors have been identified to increase square and boll abscission and thus result in reduced cotton yield. Under stress conditions, ethylene is elicited. Ethylene peaks before abscission to promote the formation of the abscission layer and plays a major role in early season square and boll abscission. Thus, it is important to protect a crop from ethylene-induced fruit shed under stress conditions. The objective of this study was to evaluate the ability of 1-methylcyclopropene (1-MCP) to protect cotton plants against abiotic stress caused by ethephon (ethylene promoting effect). Field studies with randomized complete block design with four replications were conducted in 2011 and 2012. Eight treatments consisted of two 1-MCP rates (0 and 10 g ai/ha) in combination of 4 ethephon rates (0, 2, 4, 6 oz/A) were imposed at first flower (FF) stage. 1-MCP treatment increased quantum efficiency of Photosystem II, membrane integrity, plant height, and number of mainstem nodes in both years. Lint yield was enhanced in 2011.1-MCP showed a potential to increase cotton lint yield under stressed conditions.