Premium
Canopy Temperature Depression Association with Yield of Irrigated Spring Wheat Cultivars in a Hot Climate
Author(s) -
Amani I.,
Fischer R. A.,
Reynolds M. P.
Publication year - 1996
Publication title -
journal of agronomy and crop science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.095
H-Index - 74
eISSN - 1439-037X
pISSN - 0931-2250
DOI - 10.1111/j.1439-037x.1996.tb00454.x
Subject(s) - canopy , agronomy , cultivar , stomatal conductance , sowing , poaceae , biology , grain yield , irrigation , environmental science , botany , photosynthesis
This study examines the utility of measurements of canopy temperature depression (TD) below air temperature as an indirect selection criterion for grain yield in breeding of wheat ( Triticum aestivum L.). TD differences can be rapidly assessed using a hand‐held infra‐red thermometer and may reflect differences in stomatal conductance. Replicated small plot experiments were conducted with 23–24 spring wheat cultivars planted at two dates in the winter cropping cycles of 1991–92 and 1992–93 at a hot low latitude location in Mexico. Across a two fold range in grain yield at each planting, TD was usually highly significantly correlated with grain yield. Averaging the results for each year, the phenotypic correlation TD vs. yield was 0.84** and 0.89** for 1991–92 and 1992–93, respectively. Correlations were strongest when TD was measured between noon and 4 pm, and were unaffected by crop stage of development (pre‐heading, heading, grain fill) or timing relative to irrigation. TD was positively correlated with stomatal conductance. We discuss possible causes of these high correlations, and their implications for wheat breeding.