Studies on the Photosynthetic Tissues in the Leaves of Cereal Crops : VIII. Effect of soil moisture content on the mesophyll structure of the wheat leaves.

Abstract

On the wheat plants grown under different soil moisture contents, 45-50%, 25-30% and 15-20% of the maximum water-holding capacity, the structural changes of the mesophyll or the 5th leaf blades were observed. The results obtained were as follows : 1) The length and width of the leaf blades, the mesophyll thickness and the interveinal distance decreased with decreasing soil moisture content. 2) Surface/volume ratio of the LP-type cells (longitudinally elongated arm-palisade cells) increased with decreasing soil moisture content, as a result of increase in number of protuberances and decrease in diameter of protuberances. 3) A close negative correlation was observed between surface/volume ratio of the LP-type cells and diameter of protuberances. 4) An increase in number of mesophyll cells per unit leaf area was found at the low soil moisture contents, such as 25-30% and 15-20%.