The mechanism of leaf growth inhibition was investigated in eight maize genotypes differing in drought resistance and maturity groups. In controlled conditions the effects of drought, nitrogen deficiency, pH and ABA on leaf growth were investigated. In soil drying experiment measurements of water potential and its components and leaf growth and development parameters were carried out.

The effect of drought on cell-wall peroxidase activity (bulk and spatial) was observed parallel with leaf growth parameters (leaf elongation rate - LER and segmental elongation rate - SER) in the third leaf of six maize genotypes differing in maturity grouping and drought resistance.

The distribution of weeds in maize hybrids grown in different crop densities with and without herbicide application was observed in the present study. The floristic composition and structure of weed community were estimated according to the occurrence of distributed weed species, number of their plants and their mass per area unit. These parameters were monitored as they more precisely determine competitive effects of different maize crop densities on weeds.