A fertilidade do solo e sua relação com a produção, o peso e a composição química das sementes de milho

The objective of the present work was to study the soil fertility and its relation with the production, the weight and the chemical composition of twelve corn ( Zea mays L.) cultivars seeds. The field test was carried out in soils with two distinct fertility levels. In the soil with the higher fertility a mineral fertilization containing N, P, K, B, Cu, Mo, and Zn was applied according to the corn crop requirements and the soil chemical analyses. In the soil with the lower fertility, any mineral fertilization was made. In the field test, the effects of soil fertility on the number of broken and/or layered plants, the number of healthy cobs and the number of cobs damaged by insects and/or diseases were also studied. Seeds weight soluble protein, reductor sugars, lipids and dry matter were determined in two different times. The analyses of data and the interpretation of the results led to following conclusions: a) although the higher soil fertility level had gave higher production, higher number of healthy cobs and higher seeds weight, the same did not occur in relation to seed chemical composition, once the two soil fertility levels had the same behavior in relation to this characteristic; b) the number of broken and/or layered plants was higher in the lower soil fertility level, while the number of healthy cobs was higher for the higher soil fertility level; c) the effects of the fertility levels were significant in relation to the seeds weight; for ten of the twelve tested cultivars, the weight was higher in the higher soil fertility level; d) in general, the behavior among the cultivars was similar in the studied characteristics.