Effect of weight of seed upon the resulting crop

Summary. 1 Field experiments, especially in America, nave indicated that, with annual plants at least, better crops are usually obtained by the use of heavy seed in preference to light, whether equal numbers of bushels or equal numbers of seeds are sown per acre. 2 Water culture experiments with peas and barley have shown that there is a steady and considerable rise in the dry weight of the plants as the initial weight of the seed increases. This occurs both with a limited and abundant food supply. 3 The efficiency index (rate per cent, increase per day) falls gradually as the weight of the seed rises. With prolonged periods of growth this tends ultimately to counterbalance the initial advantage gained by plants from the heavier seeds, but with annual crops as cereals, peas, etc. harvesting occurs before this equilibrium is reached, leaving the advantage with the heavier seeds. 4 The relative development of shoot and root is to some extent influenced by the initial weight of the seed, but may vary with the species and with the amount of available food. 5 The results lend support to the growing agricultural practice of advocating the use of large heavy seed, especially with annual crops. The advantage in the case of perennials would appear to be less, if any, but this has not been determined by laboratory experiments.