Relationship between climate and relative performance of cotton in New South Wales

Abstract

Cumulative day-degrees, total rainfall and the mean daily values for evaporation rate, maximum temperature, minimum temperature and radiation for a period of 200 days from 1 October to 18 April were used to characterize the climates of cotton-growing seasons at Narrabri (30¦S.), N.S.W. Yields (expressed as percentages of standards) of some cultivars included in field trials in cotton-growing districts of New South Wales, were then regressed on these climatic indices. In a number of cases strong, significant linear associations of performance with one or more of the indices were found. Such cultivars were either more or less advantaged by warm, dry conditions than the standards, and vice versa for cool, wet conditions. The implications of these results in studies of genotype x environmental interaction are discussed.