On the Stomatal Frequency in Barley. : II. Intra-plant variation, vari-etal difference and heritability of stomatal frequency.

Intra-plant variation, varietal difference and heritability of stomatal Lrequency were studied in barley. Stomatal frequency on leaf decreased from flag (L1) to lower leaves. Stomatal frequency on L1 sheath was comparable to that on L4 leaf. Total stomata of awns on one head, estimated from the number of awns per head and the number of stomata per awn, and total stomata on L1 sheath were about as many as those on upper and lower leaf surfaces of flag leaf (Table 3). Cultivars of high stomatal frequency on flag leaf showed higher stomatal frequency on the other leaves and sheaths compared with those of low stomatal frequency on ffag leaf (Fig. 2). Correlation coefficients between stomatal frequency on flag leaf (lower surface) and those on the other leaves or sheaths were high (Table 5). Stomatal frequency on flag leaf (lower surLace) of 384 cultivars differed significantly, ranging from 43 to 95 stomata per mm2. Stomatal frequencies on flag leaf (lower surface) of 7 cultivars grown in two different seasons were highly correlated (r=0. 93) (Fig. 3).