Low-temperature induced floret sterility in the rice cultivars Calrose and Inga as influenced by nitrogen supply

Abstract

An experiment in temperature-controlled glasshouse chambers at Yanco Agricultural Institute examined floret sterility in lnga and Calrose rice induced by low temperature and high nitrogen level. Low temperature (12�C) ,for 4 d during microsporogenesis and anthesis produced considerable sterility in both cultivars; lnga was more sensitive than Calrose. Sensitivity was greatest when florets from the mid-section of the panicle were passing through the early microspore phase of pollen development. At both stages, the amount of low-temperature induced sterility was increased by high nitrogen supply. In the absence of low temperature, high nitrogen levels induced sterility in lnga only.