The effect of fertilizers on germination and seedling growth
1923
Sherwin, M.E.
The results of experiments in germinating corn and cotton seeds in different types of soil, either with the seeds in direct contact with various fertilizers or with the same fertilizers mixed with the soil in which the seeds are planted, appear to indicate clearly the following effects of the fertilizers upon the germination and seedling growth of both types of crops. Germination is generally inhibited by the presence of the fertilizers. This inhibition is greater when the fertilizer is in direct contact with the seed than when it is mixed with the soil. The amount of inhibition is generally proportional to the amount of fertilizer used, and is greater with the more soluble mineral fertilizers than with the less soluble mineral or the organic materials. The inhibiting action is apparently not due to a direct effect of the fertilizers upon the viability of the seed, but to a retarding influence upon the osmotic absorption of water from the soil by the seed, in the case of the soluble mineral fertilizers, or to the stimulation of the growth of fungi, especially molds, which are injurious to the root systems of the young seedlings, by the presence of organic fertilizers like cottonseed meal. Borax, in amounts as small as three and one-half pounds per acre, exerts a marked inhibiting effect upon root growth, which is not counteracted by the addition of ferrous sulfate in solution.
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