Differences in stomatal number per unit area within the same species under different micro-environmental conditions: A working hypothesis

Eduardo Lleras

doi:10.1590/1809-43921977074473

Abstract

Abstract A summary of Salisbury's (1927) work on stomata is presented here. He found, basically, that the number of stomata per unit area increased under more xerophytic conditions. This is contrary to prevalent opinion, that postulates that under more humid conditions, the number of stomata can be greater, as there is less danger of dehydration. A hypothesis is presented here that can explain this: The more xerophytic the conditions, the higher the number of stomata per unit area to permit more efficient gas interchange at those times when relative humidity is high, and danger of excessive dehydration is lowest.

Highlights

A summary of Salisbury's (1927) work on stomata is presented here
In spite of the great amount of work done on stomata, little or no attention has been paid until recently to the variation in stomatal numbers within the same species
In a majority of cases, stomatal number are usually assumed to be fairly constant within certain lim its, and are cited as such

Summary

Introduction

A summary of Salisbury's (1927) work on stomata is presented here. He found, basically, that the number of stomata per unit area increased under more xerophytic conditions. Salisbury notes that there is a negative correlation between number of stomata and leaf area. He notes that there is a frequency gradient in stomatal numbers associated with height above the ground.

Results

Conclusion