A yield analysis of three varieties of barley

A yield analysis of three varieties of barley, Pedigree, Velvet, and Spartan, growing in drill plats, was made by taking plants from 50 1-foot sections of drill row located at random from each of two plats of a variety. The plats were approximately 1/24 of an acre in size. The data were reduced to a plant basis. The stands within the sampled sections ranged from 2 to 27 plants per foot. Variation in stand was probably due primarily to the unequal distribution of seed by the drill in addition to other causes which affect seedling survival. Spartan produced an average of 2.34; Wisconsin Pedigree, 1.30; and Velvet, 1.19 heads per plant. This significant varietal difference in average head production per plant was considered to be inherent. Variation in soil fertility was probably not a serious factor, while differences in size of seed and thickness of stand had only slight effect. The rate of yield in bushels per acre was velvet, 46.08; Wisconsin Pedigree, 45.52; and Sparta 42.85. Yield per unit was more closely, associated with the number of heads than with the number of plants per unit area. Average yield per plant depended upon the average number of heads per plant and the average weight of grain produced per head. Average yield of grain per head was Wisconsin Pedigree, 0.99 gram; Velvet, 0.89 gram; and Spartan, 0.57 gram. Average weight of grain produced per head varied with the variety, number of heads per plant, class of tiller, and average kernel weight. In total yield for the entire area studied, Velvet was first, Wisconsin Pedigree second, and Spartan third. The order was the same for total number of plants. Spartan, while superior to the other varieties in average yield per plant, had a smaller rate of yield because of a smaller total number of plants, and for the same reason Wisconsin Pedigree yielded less than Velvet. The yield characteristics of a variety can best be determined by a study of single plants. Information derived from such a study is of value to the plant breeder in choosing varieties for crossing in an attempt to combine all of the desirable plant-yield characters. The analysis showed that if seeded at the same rate (pounds per acre) a small-seeded variety may outyield a large-seeded variety on account of the larger number of plants per unit area rather than because of superior plant-yield characters.