The influence of nutrition on the response of wheat triticum aestivum cultivar gabo to above optimal temperature
Dawson, I.A.; Wardlaw, I.F.
Australian Journal of Agricultural Research 35(2): 129-138
ISSN/ISBN: 0004-9409 Accession: 006699070
Wheat plants were grown at 2 temperatures (18.degree./13.degree. and 24.degree./19.degree. C, day/night), either with full nutrient availability or deprived of nutrients after floral initiation or after anthesis, in order to identify possible interactions between nutrient availability and response to a temperature higher than the optimum for grain dry weight accumulation. Nutrient deprivation reduced levels of N, K and Ca in the vegetative organs of the plant at anthesis and maturity, and levels of N and Ca, but not K in the grain. Differences in the distribution of N, K and Ca can be explained on the basis of their phloem mobility. An interaction was observed between nutrition and temperature in the time from seedling emergence to anthesis, the number of tillers at anthesis and the number of heads per plant at maturity. Within the main culm ear, high temperature and low nutrition reduced grain number. High temperature, but not low nutrition, reduced individual grain weights. There were no interactions between nutrition and temperature in regulating these responses. Although nutrition may be an important factor when considering the effect of temperature on tillering, there is no evidence from this study that nutritional status will mask the effects of temperature on the later stages of ear and grain development.