Changes in stomatal response characteristics of grain sorghum produced by water stress during growth.
by McCree K. J. (1974)
in Crop Sci. 1974;14:273–278. – doi:10.2135/cropsci1974.0011183X001400020032x –
Experiments were designed to test the hypothesis that stomatal response characteristics can be modified by growing the test plants under water stress. Different degrees of stress were obtained by varying the atmospheric demand and by allowing the soil to dry.
Hybrid grain sorghum (Sorghum bicolor (L.) Moench. CV. ‘Oro’) was grown in nutrient culture, under atmospheric conditions which simulated natural daily cycles of temperature and dew point, at constant light level and carbon dioxide concentration.
Thirty days after planting, the diffusion resistances of fully expanded leaves were measured as functions of light level (at constant leaf water potential) and of leaf water potential (at constant light level), with the leaf temperature and ambient carbon dioxide concentration being kept constant.
The responses of leaves grown in “hot, dry” and “warm, humid” atmospheric conditions were very similar to one another, but leaves which had been subjected to five cycles of moderate soil moisture stress, as well as ‘hot, dry’ atmospheric conditions, had stomates which were less responsive to decreasing leaf water potential than the stomates of leaves grown under well-watered, conditions.
These changes are in the right direction to explain differences which have been observed between growth chamber and field-grown material.