High-temperature injury to early development of tapetum cells in barley Hordeum vulgare L.

Abstract

We have studied effects of high temperature stress on reproductive development in barley plants. Exposed to high temperature (30°C day/25°C night) for five days at the panicle differentiation stage, the following pollen development was completely aborted. In this study, we found that the abortion was due to the defect of early development of tapetum cells. In addition, expression levels of histone H3 and H4 family genes didn't increase in the abortive panicles, whose levels particularly increased under normal condition. Expression levels of housekeeping genes such as a 60S ribosomal protein gene also decreased. In order to identify whether such a high temperature generally affected vegetative growth and somatic cell division, we measured each growth curve of two types of culture cells and young shoots at 30°C. The results indicate that the high temperature specifically affects the early development of tapetum cells.