Studies on the Photosynthetic Tissues in the Leaves of Cereal Crops. : VI. Effect of nitrogen nutrition on the mesophyll structure of leaves in rice varieties of different plant types

[摘要] Plants of different types of rice varieties, Sasanishiki and Kamenoo, were grown in pots with different levels of nitrogen, and the mesophyll structural changes of leaves were observed. In Kamenoo, the typical panicle weight type, the ratio of the mesophyll surface area to the leaf area (MS/LA) and the number of protuberances developed by each mesophyll cell were decreased by application of nitrogen. In Sasanishiki, the typical panicle number type, these structural changes of the mesophyll were not so remarkable as those in Kamenoo. In longitudinal sections of both varieties, the intercellular spaces area in the mesophyll was increased in proportion to the amount of applied nitrogen. So far as the unit leaf area was concerned, the number of mesophyll cells was decreased by application of nitrogen. Flowever, the total cell surface area was hardly reduced because of increase in surface area of each mesophyll cell, and this trend was more evident in Sasanishiki than in Kamenoo. From the results of this experiment, it was suggested that the application of nitrogen might bring about a favourable structure for gaseous diffusion in the mesophyll.

[学科分类] 农业科学（综合）