Abiotic stress effects on plant growth and yield components of 1-MCP treated cotton plants.

摘要

Boll abortion is increased when cotton (Gossypium hirsutum L.) experiences various stresses during its reproductive development that can consequently reduce lint yield. Before abscission, an increase in ethylene is observed which may be assumed to be the signal necessary to initiate abscission of that particular structure. It is desirable to prevent fruit loss that may be induced by the peak in ethylene before abscission. One potential option to cope with the loss of cotton reproductive structures is the use of ethylene inhibitors. Thus, the objective of this investigation was to determine the impact of 1-methylcyclopropene (1-MCP) on growth and yield components of cotton plants treated with ethephon (ethylene synthetic hormone) under field conditions. Field studies were conducted as a randomized complete block design with four replications in 2007 and 2008. Treatments were three rates of 1-MCP in combination with a surfactant applied at mid-bloom. One day later, ethephon was applied as a source of abiotic stress. At harvest, the fruit set in the upper portion of the canopy was influenced by 1-MCP. It had a greater number of full size, yet immature bolls, which potentially could have had a positive influence in the lint yield. However, ethephon caused the highest lint yield since ethephon-treated plants had more open as well as total bolls in the lower canopy at harvest. In conclusion, 1-MCP improved growth and yield components mainly in the upper portion of plants canopy at harvest, but such an improvement was not converted into lint yield.