Water deficits cause major yield reductions on the world's rainfed riceland. The most severe water deficits occur during the reproductive phase. Differences in canopy temperature among crop cultivars are known to be related to drought avoidance characters. In developing a practical field screening system for reproductive phase drought resistance in rice (Oryza sativa L.), we assessed the canopy temperature response of a range of germplasm, and related the results to other plant characters related to drought resistance. Field experiments were conducted on a silty clay loam Typic Hapludoll at the International Rice Research Institute. Planting of the test cultivars was staggered, to synchronize flowering during the water-deficit period. Canopy temperature measurements were made on 12 dates in Trial 1 and 8 dates in Trial 2. Mean canopy temperatures (Tc) increased from 28 to 37 degrees C during the stress period. Grain yield (r2 = -0.63**) and spikelet fertility (r2 = 051**) were related to midday Tc on the day of flowering. Highly significant differences were observed in canopy temperature among entries, with low coefficients of variation (2.0-2.7%). Entries with a history of outstanding vegetative stage drought screening scores consistently remained coolest under stress. Visual drought tolerance scores (r = 0.72**) and leaf rolling scores (r = 0.68**) were correlated with mean canopy temperatures under moderate water stress, but not under severe stress (r =
DOI:
https://doi.org/10.2134/agronj1995.00021962008700040027xScore Altmetric:
Dimensions Nombre de citations:
Année de publication
1995
Auteurs
Langue
English
Mots clés
water depletion, crop yield, canopy, temperature, growth rate
Géographique
Indonesia
