Premium
Determining the Optimum Plant Temperature of Cotton Physiology and Yield to Improve Plant‐Based Irrigation Scheduling
Author(s) -
Conaty W.C.,
Burke J. J.,
Mahan J. R.,
Neilsen J. E.,
Sutton B. G.
Publication year - 2012
Publication title -
crop science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.76
H-Index - 147
eISSN - 1435-0653
pISSN - 0011-183X
DOI - 10.2135/cropsci2011.11.0581
Subject(s) - irrigation , cultivar , canopy , irrigation scheduling , biology , stomatal conductance , fiber crop , agronomy , yield (engineering) , horticulture , gossypium hirsutum , photosynthesis , botany , materials science , metallurgy
A plant‐based thermal optimum approach to irrigation scheduling provides potential benefits in that water applications are scheduled on the basis of plant response to water status. Such irrigation systems require a defined thermal optimum for the crop and while such optimum values have been identified for cotton ( Gossypium hirsutum L.) cultivars in the United States, there is no information of this type for cultivars common in Australian production. This paper outlines a threefold approach to determining the optimum temperature (T opt ) of the commercial Australian cotton cultivar Sicot 70BRF in an Australian production system. It combines the use of a laboratory‐based fluorescence assay, field‐based net C assimilation rate (A) and stomatal conductance to water vapor (g s ), and canopy temperature (T c )–yield relations. The fluorescence assay showed a T opt between 28 and 30°C while leaf gas exchange rates peaked at a leaf temperature (T l ) of 29°C. The T c –yield relations peaked at 26°C, with yield reductions observed when T c > 28°C. We conclude the T opt of the Australian upland cotton cultivar Sicot 70BRF to be 28 ± 2°C. This T opt will provide valuable information for use in thermal optimum irrigation scheduling systems.