STOMATAL FREQUENCY AND DISTRIBUTION ON THE INFLORESCENCE OF <i>TRITICUM AESTIVUM</i>

Abstract

Stomatal distribution and frequency on the lemma, palea, glume, and awn were determined by counting the stomata per unit area on the various components of the wheat spikelet. Stomata occurred in rows on the abaxial surface of the lemmas and glumes. The portion of the lemma covered by a glume or adjacent lemma did not have stomata. A single row of stomata extended down each side of the crease of the palea. Each awn had two parallel rows of stomata at the base; the rows spiraled up the awn and were reduced to one row at the tip. We found that inflorescence stomata ranged from 15000 to 60000; awn stomata from 100 to 13000; palea stomata, from 2000 to 10000; lemma stomata, from 6000 to 22000; and glume stomata, from 6000 to 20000. Number of stomata per inflorescence represented 3–16% of the flag-leaf stomata/culm. The characterization of 19 cultivars of Triticum aestivum in relation to stomata numbers per inflorescence shows a wide range of variation that may be useful in future breeding programs.