Do Really Close Stomata by Soil Drying ABA Produced in the Roots and Transported in Transpiration Stream?
نویسنده
چکیده
Stomatal aperture responses of Commelina communis L. between well watered plants and water stressed plants were investigated. To see the very rapid response to water stress, the plants were directly rooted out from the soil and exposed to the air immediately. Stomata, rooted out from the soil, were totally closed within 10 minutes without any detention time while the stomata of the plants in the soil had been kept opening. These results suggest that stomatal response to the abrupt water stress is very rapid indicating that guard cell itself or leaves could sense water status in the plants.
منابع مشابه
How Do Chemical Signals Work in Plants that Grow in Drying Soil?
We have known for many years that the dehydration of plant cells can lead to accumulation of the plant growth regulator ABA. Application of this compound to well-watered plants mimics many of the effects of soil drymg on gene expression, physiology, growth, and development, making this compound a strong candidate for a role in the droughted plant. Dehydration of leaves can result in massive acc...
متن کاملRoot water potential integrates discrete soil physical properties to influence ABA signalling during partial rootzone drying.
To investigate the influence of different growing substrates (two mineral, two organic) on root xylem ABA concentration ([ABA](root)) and the contribution of the drying root system to total sap flow during partial rootzone drying (PRD), sunflower (Helianthus annuus L.) shoots were grafted onto the root systems of two plants grown in separate pots. Sap flow through each hypocotyl was measured be...
متن کاملNitrate signalling to stomata and growing leaves: interactions with soil drying, ABA, and xylem sap pH in maize.
Increasing the nitrate (N) concentration in the rooting substrate above deficiency decreased stomatal conductance and leaf growth rate compared with sufficient N in maize seedlings (Zea mays L.) growing in drying substrate. Novel effects were detected when N in the non-deficient range was supplied directly to the xylem of detached shoots: concentrations above 2.0 mol m-3 KNO3 reduced transpirat...
متن کاملABA-Mediated Stomatal Response in Regulating Water Use during the Development of Terminal Drought in Wheat
End-of-season drought or "terminal drought," which occurs after flowering, is considered the most significant abiotic stress affecting crop yields. Wheat crop production in Mediterranean-type environments is often exposed to terminal drought due to decreasing rainfall and rapid increases in temperature and evapotranspiration during spring when wheat crops enter the reproductive stage. Under suc...
متن کاملHormonal changes induced by partial rootzone drying of irrigated grapevine.
Partial rootzone drying (PRD) is a new irrigation technique which improves the water use efficiency (by up to 50%) of wine grape production without significant crop reduction. The technique was developed on the basis of knowledge of the mechanisms controlling transpiration and requires that approximately half of the root system is always maintained in a dry or drying state while the remainder o...
متن کامل