Water Absorption of Alfalfa as Affected by Low Root Temperature and Other Factors of a Controlled Environment¹

Abstract

Synopsis Water deficit and wilting can be caused by low root temperatures, even though the water supply is not limiting. To predict wilting it is necessary to know the transpirational demand, the root temperature, and the duration of subnormal temperature.

Photosynthesis in Sitka Spruce (Picea sitchensis (Bong.) Carr. IV. Response to Soil Temperature

“…The observation that no reduction in the rates of photosynthesis or transpiration occurred in Sitka spruce until the soil temperature was below 10C contrasts with many previous studies on other species (Kramer 1940(Kramer , 1942Kozlowski 1943;Bohning & Lusanandana 1952;Abdel Rahman, Kuiper & Bierhuizen 1959;Brouwer 1961;Ehrler 1963;Kuiper 1964;Cox & Boersma 1967;Babalola et al 1968;Benecke 1971;Havranek 1972;Rutland & Pallas 1972;Janes 1973), but is in agreement with two recent studies in which no reduction in photosynthesis or transpiration was observed at soil temperatures of 3YC, or above, in Scots pine and Norway spruce (Linder 1973) and in a diverse range of species of vascular plants (Anderson & McNaughton 1973). Differences amongst species have been interpreted as showing that the permeability of the roots is reduced to different extents by low temperature (Kramer 1969).…”

Plant Water Status and Carbon Dioxide Exchange of Cotton Leaves

“…Arndt (1937) noted wilting in young cotton plants when the roots were cooled, even when the roots were in nutrient solution. This influence of root temperature on leaf water content is well established (Kramer 1949;Ehrler 1963;Cox and Boer.sma 1967), and a reason suggested by Kramer (1949) for this effect is an influence on cell permeability. Kuiper (1963Kuiper ( , 1964 has shown that low root temperatures reduce the uptake of water but that the QIO for water uptake of 3·8 can be reduced to 1·18 by the application of alkenyl succinic acid which is suggested to influence membrane permeability.…”

Effect of root zone temperature on early growth, nodulation and nitrogen fixation in soya beans

“…Low RT is known to affect rate of plant growth in various species by restricting water (Ehrler, 1963;Nelson, 1967;Abdelhafeez et al 1971), mineral uptake (Nielson et al 1961;Grobelaar, 1963;Wallace et al 1969) and translocation (Smith & McCully, 1977) within the plant which may cause water stress within the above-ground organs, particularly the leaves. A major effect of water stress is to restrict leaf expansion and in these studies leaf area was much more affected than leaf production by low RT.…”