The Response to High Temperature Shock and Humidity Changes Prior to and During the Early Stages of Grain Development in Wheat

Transferring wheat (Triticum aestivum L. cv. Banks) from 21/16°C to high temperature (36/31°C) for intervals of 2 days in the period from head emergence to 10 days after anthesis resulted in grain sterility and specific forms of morphological and cellular damage depending on the stage of development of the grain at the time of transfer. Grain sterility was induced by high temperature 2-3 days prior to anthesis and this response was found to be considerably enhanced by high humidity. Parthenocarpic, abortive and shrunken grain were induced by high temperature between anthesis and 3 days after anthesis. High temperature from 6 to 10 days after anthesis resulted in notched, split and opaque grains.