The influence of fertilizers, manures, and lime on the plant and seed characters of wheat and corn and on their yield trend
Under the conditions of the Rotation Experiment with Fertilizers, the following results were obtained with corn:
The phosphorous plat, complete fertilizer plat and the manure plats produced a much higher yield of corn than the check plat. Also, these plats produced a higher percentage of marketable grain than the other plats.
There was not much difference in the shelling percentage from the various plats but it was somewhat lower on the nitrogen and the floats plats.
The nitrogen-phosphorous plat produced the greatest number pounds of shelled corn per pound of stover. The complete fertilizer plat also produced a high percentage of grain to stover.
The percentage of matured ears was greatly increased on the nitrogen-phosphorous plat and the three manure plats.
The corn plants on the manure plat developed sooner than those on the other plats while those of the check plat developed later. Also, the plants were larger in circumference and in height on the manured plat.
The means of the corn characters were greater on the fertilized plats than on the check plat, and the means increased as the productivity increased.
On the whole, the constants of variation were greater on the fertilized plats than on the check plat. The differences were sufficiently great to indicate that they were significant. On the whole, the coefficients of correlation of the corn characters were greater on the fertilized plats than on the check plat but the odds do not show that they are significant. Opposite results were obtained with wheat which is shown in Table 9. Also, in the case of wheat, the odds on the whole are not significant .
In summing up all of the data in this experiment, it may be said that manure and acid phosphate were the chief limiting factors affecting yield. High yield of corn is usually accompanied by a high percentage of marketable grain, high shelling percentage, high ratio of grain to stover, high percentage of matured ears, and early maturity of plants.