EFFECT OF SELECTION FOR STOMATAL Length AND FREQUENCY ON THEORETICAL STOMATAL RESISTANCE TO DIFFUSION IN LOLIUM PERENNE L.

Abstract

A population of Lolium perenne L.‘Grasslands Ruanui’ grown in a controlled environment, exhibited much phenotypic variation in stomatal resistance to diffusion (rs) as calculated from stomatal dimensions and frequency. Direct selection for rs was comparatively ineffective and the heritability was low (about 0.22) because of a negative correlation between stomatal length and stomatal frequency. However, selection for frequent and infrequent stomata resulted in a marked correlated genetic shift in the F1 generation toward respectively low and high rs at a given pore opening. Further selection for stomatal frequency did not affect rs and response by frequency itself was much reduced in the F2. Selection for stomatal length had no effect on rsin the F1 but there was a slight reduction in rs in the F2 long stomata selection. Copyright © 1972, Wiley Blackwell. All rights reserved