Prominent Difference of Glycerolipids among Anther Walls, Pollen Grains and Leaves of Rice and Maize

Fatty acid compositions of glycerolipids of anther walls, pollen grains and leaves of rice andmaize were compared. Stearic acid amounted to about 20% and 10% of the total fatty acids inanther walls from rice and maize, respectively, whereas its content was only 1-3% in the other organs of both plants. Stearic acid existed at high levels in all lipid classes of anther walls fromrice and maize except for maize monogalactosyldiacylglycerol. Stearic acid was esterified mainlyto the C-l position of Jrt-glycerol in all lipid classes. When the fatty acid composition of lipids from rice anther walls was compared with that of rice leaves, a-linolenic acid was replaced bystearic acid in monogalactosyldiacylglycerol, digalactosyldiacylglycerol, sulfoquinovosyldiacylglyceroland phosphatidylethanolamine, and palmitic acid was replaced by stearic acid in phosphatidylcholineand phosphatidylinositol. The possibility is discussed that the high content of stearic acid in anther walls is related to the high sensitivity of anthers to chilling.