| Extreme year-to-year temperature variability leads to unpredictable yields in cotton, because high temperature is correlated with excessive boll shedding and poor boll filling. The ability of 1-Methylcyclopropene (1-MCP), an ethylene inhibitor, to improve yields and ameliorate high temperature stress was evaluated in the field and the growth chamber. The plant stress response was gauged by measuring levels of antioxidant enzymes, which are thought to increase during stress, and by measuring levels of adenosine triphosphate (ATP) and malondialdehyde (MDA), which are thought to decrease during stress. There were no significant differences between the control group and the 1-MCP treatments in any of the biochemical measurements. Lint yield, seedcotton yield, seed number, boll number, and boll weight were also measured, but no significant differences were observed between the control group and the 1-MCP treatments. Results showed that although there was no significant effect of 1-MCP treatment on lint yield in 2008, a positive trend was visible over the three years of the study. In the growth chamber and the greenhouse, 1-MCP significantly increased plant height. This effect of 1-MCP may be useful to help stunted cotton recover from stress during the vegetative stage. |
