In an intensive apple orchard we examined the influence of the width of the herbicide zone on vegetative and generative activity of apple trees. In a factorial trial based on randomised blocks, which lasted four years, we studied three different widths of the herbicide zone under trees (25, 50 and 100 cm), and the zone under trees which was covered by weeds and other plant species, and mowed (the fourth treatment). We found out that the width of the herbicide zone had a significant influence on the growth and cropping of apple trees. The trees under which soil was covered by weeds and other plants, and trees on a 25 cm wide herbicide zone expressed lower vegetative and generative activity. The trees on a wider herbicide zone were characterised by more intense vegetative growth (expressed as the increase of the trunk diameter) and higher generative activity (expressed as the number of developed inflorescences, fruit yield and the first-class fruit yield). The study suggests that adequate width of herbicide zone is a necessity for achieving a higher yield and a high apple fruit quality.

Key words: fruit growing, apple Malus domestica plantations, weed control, herbicide zone, growth, fertility, plant communities/yield

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