Vegetation conditions essentially affect distribution of plants in agropopulation of durum wheat on classes of a variation number of spikelets, quantities kernels an ear and their weight. Among cultivars of the Saratov selection in the conditions of extreme year on agroclimatic conditions it is characteristic various number of plants: to age–old cultivars – the small classes, to new cultivars – the big classes of a variation. Favorable agroclimatic conditions raise number of the plants carried to higher classes of a variation of elements of efficiency of an ear.