Abstract
The physiological and physical components of the feedback loop involving intercellular CO2 concentration (ci) and stomata are identified. The loop gain (G) is a measure of the degree of homeostasis in a negative feedback loop [the expression 1/(1-G) represents the fraction to which feedback reduces a perturbance]. Estimates are given for the effects of G on responses of stomata and ci to changes in ambient CO2 concentration, light intensity, and perturbations in the water relations of a leaf. At normal ambient CO2 concentration, the gain of the loop involving stomatal conductance and ci was found to be −2.2 in field-grown Zea mays, −3.6 if plants of this species were grown in a growth chamber, and zero in well watered Xanthium strumarium in the vegetative state.
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Selected References
These references are in PubMed. This may not be the complete list of references from this article.
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