Effects of high temperature on pollen performance in ever-bearing strawberry cultivars

摘要

High temperature stress can affect the growth and development of pollen, which in turn can influence fruit set and seed development. The effects of high temperature on pollen performance have been evaluated in two ever-bearing strawberry (Fragaria x ananassa Duch.) cultivars ('Charlotte' and 'Goha') for a glasshouse and plastic house in Daegwallyeong Research Center, Gangwon Province, South Korea from June to August 2013. Different cultivars showed different results for most observations. The flowerinitiation for 'Goha' was earlier than 'Charlotte'. Besides, pollen viability and pollen germination, number of flowers, number of fruits, and fruit weight plant1 for 'Goha' were higher than 'Charlotte'. But, the percentage of abnormal fruits for 'Charlotte' was higher than 'Goha'. Different temperatures between the glasshouse and plastic house affected pollen viability, pollen germination, flower initiation, time of flowering to fruit maturity, percentage of flower to fruit conversion, and percentage of malformed fruits. The glasshouse with mean dayight temperature (26/21°C) reduced pollen viability and pollen germination, accelerated flower initiation, accelerated time of flowering to fruit maturity but decreased conversion from flower to fruit compared to strawberry plants in the plastic house with mean dayight temperature (25/18°CJ. Higher temperature for the glasshouse resulted in higher number of flowers but also resulted in higher percentage of malformed fruits. These results suggested that high temperature in ever-bearing strawberries was associated with reduced pollen performance.