With the quickening industrialization, the worsening environment and the global warming, heat injury is becoming a major disasterous factors that has an effect on crop growth, and is receiving increasing concern because of its limiting effect on rice production.
The experiments were carried out in growth chamber to investigate the effects of high temperature stress during heading and flowering period on pollen characters and anther microstructure using two rice lines including heat-tolerant line 996 and heat-sensitive line 4628.Seven day/night temperature(8:00-17:00,37℃;17:00-8:00,30℃) after heading were established. The results showed that anther dehiscence coefficient and pollen grains on the stigma significantly decreased, pollen diameter significantly increased under high temperature stress, pollen vigor and pollen germination rate decreased during the stress period. Anther dehiscence coefficient, pollen diameter, pollen vigor, pollen germination rate and pollen grains on the stigma in heat-tolerant line 996 were significantly higher than that of heat-sensitive line 4628 under high temperature stress, this indicated that heat-tolerant line 996 was able to keep better pollen grain pollination and germination character under high temperature stress, and was physiological basis of heat-tolerant line; Under high temperature stress, epidern cell of anther wall in vascular bundle of connective tissue in heat-tolerant line 996 arranged regularly and tightly, vascular bundle sheath cell and parenchyma cells arranged regularly, xylem and phloem were clear. While epidern cell of anther wall in heat-sensitive line 4628 arranged irregularly and untightly, vascular bundle of connective tissue was seriously destroyed, and vascular bundle sheath cell arranged irregularly, xylem and phloem were unclear.