Effects of high temperature on the microsporogenesis and pollen development of peach.

Effects of high temperature on microsporogenesis and pollen development of ‘Jinxiu’ yellow peach was studied in artificial climate chamber.The results showed that:There was no significant difference between pollen quantity in anthers treated under 35 ℃ for an hour and that under control(20 ℃).With increasing duration of high temperature(35 ℃)treatment,quantity,germination rate and length of pollen tubes significantly decreased.While the duration reached to 5 hours,pollen quantity was as only 1.9 % of the control,also showed nearly no bourgeon.Some pollen mother cells under 5 hours of 35 ℃ can not generate normal tetrad,but form dyad,triad and polyad,further,multinuclear microspores appeared along with callose degradation.After high temperature treatment,cytoplasm of microspores contracted and degenerated,also followed with microspores wall degradation.As regards cells of anther wall they were dyed light,due to the early disintegrated of tapetum cells.It was suggested that disappearance of microspore be induced by the disability of nutrition supply from tapetum cells.