Grain yield and quality of wheat as affected by chlormequat (2‐chloroethyl‐trimethyl ammonium chloride)

Abstract

Three field experiments studying the effect of chlormequat (CCC) on the grain yield of spring wheat and the quality of the grain for baking purposes were made. I n the first, CCC applied as a spray during the stage of rapid internode elongation proved more successful than application as a mixture with superphosphate drilled with the seed at sowing. Both methods prevented lodging and the depression of yield which occurred in the control plots. I n the other two experiments the sole method of CCC application was by spraying.In all three experiments CCC-treated plots had more ears per unit area and grains per ear than control plots; the one exception being at the lowest plant density derived from a seeding rate of 24 kg/ha. CCC helped prevent weather damage to the grain and as a result baking performance of the flour from treated plots was superior to that from the untreated plots. I N T R O D U C T I O NIn Europe much information has been collected on the use of chlormequat (CCC : 2-chloroethyl-trimethyl-ammonium chloride) for the commercial production of wheat. This has been well reviewed by Humphries (1968) and at the joint meeting of the cereal and physiology sections of Eucarpia, Wageningen, 1967, at which the introductory paper was given by Morgan (1968).The general principles that have emerged from the published results are that ccc (a) may be used to control lodging induced by weather, disease, or excessive vegetative growth resulting from large amounts of nitrogenous fertilizer, (b) may increase the drought tolerance of plants when adequate moisture is not available, (c) sometimes produces increases in grain yield through either or all of the following effects: (i) increasing the survival of tillers to form ears, (ii) increasing the number of grains per ear, (iii) delaying senescence of the upper parts of the plant and hence extending the grain-filling period.