The present invention provides a method of improving the yield or water use efficiency in crops of useful plants cultivated under deficit irrigation which comprises the application of an agrochemical compound to the plant, parts of such plant, plant propagation material, or at its locus of growth, wherein the agrochemical compound is selected from the strobilurins, the neonicotinoids, the azoles, the SAR-inducing compounds, certain plant growth regulators (PGRs) and mixtures of such compounds.