Investigations on the rôle of organic matter in plant nutrition Part VI. Effect of injecting Minute quantities of certain forms of organic matter on plant growth and reproduction

Abstract

(1) Injection of minute quantities of certain organic extracts into mature sunflower plants led to not only better growth but also greatly increased flowering and seeding. The best results were obtained in the case of plants receiving extract of yeast or farmyard manure: the total yield of flower and seed was nearly tripled and the ratio of seed to the rest of the plant nearly doubled as compared with the untreated (control) plants. Dried blood was comparatively ineffective. Injection into tender plants did not lead to any significant improvement in yield. (2) Comparative trials with inorganic salts which were fed directly to pot-or plot-cultured French beans or barley did not lead to any marked improvement, more satisfactory results being obtained by applying the same salts (though in larger quantities) to the soil. In the latter case, the beneficial effects could be traced to increased assimilation and better general development rather than to any alteration in the ratio of seed (pod or grain) to the rest of the plant. (3) The practical significance of the above and other observations has been discussed.