Mechanisms of Reproductive Thermotolerance in Gossypium hirsutum: The Effect of Genotype and Exogenous Calcium Application

作者：Snider J L^*; Oosterhuis D M; Kawakami E M

来源：Journal of Agronomy and Crop Science, 2011, 197(3): 228-236.

DOI：10.1111/j.1439-037X.2010.00457.x

• antioxidants
• calcium
• fertilization
• Gossypium hirsutum
• heat stress

Although photosynthetic thermotolerance has been investigated extensively in cotton leaves, reports on the biochemical influence of the pistil in promoting fertilization thermostability are limited. To evaluate the effect of temperature, genotype, and exogenous calcium application on fertilization and pistil biochemistry in cotton, thermosensitive (cv. ST4554 B2RF) and thermotolerant (cv. VH260) plants were grown under control (30/20 degrees C) or high-temperature (38/20 degrees C) conditions during flowering, and exogenous CaCl(2) was applied to flowers 1 day prior to anthesis. Measured pistil parameters included fertilization efficiency; protein concentration; glutathione reductase, superoxide dismutase (SOD) and NADPH oxidase activities; and ATP and calcium levels. Exogenous calcium had no effect on reproductive thermostability due to poor calcium uptake under high temperature. High temperature resulted in a 19.2 % decline in fertilization efficiency for ST4554 but no change in fertilization efficiency for VH260 relative to optimal temperature conditions. Pre-stress glutathione reductase and SOD activities were higher in VH260 than ST4554 pistils, and calcium and ATP content were higher in VH260 than ST4554 pistils. It was concluded that pre-stress antioxidant enzyme activity, ATP and calcium content of the pistil may be associated with reproductive thermotolerance in cotton. These findings should be confirmed in future experiments with a larger number of cultivars.

• 出版日期2011-6