Technological and ecological assessment of weed infestation in different crop fields in a biological crop rotation

Totka Mitova, Iliana Gerasimova

Резюме: The successful weed control in organic farming requires system approach with different management practices and the crop rotations are a fundamental part of the ecological strategies. Understanding factors that influence on the weed diversity and community structure are very important to create strategy for effective weed control in organic systems. The goal of the present study is technological and ecological assessment of weed infestation as a result of alternating different crops in three-field crop rotation and applied organic practices. Shannon-Wiener index (H’), evenness index (J’), Simpson dominance index (D) were applied to evaluate weed community structure. The results show that diversified crop rotation, including two row crops (green bean, Phaseolus vulgaris L and potato, Solanum tuberosum L.) and changing three different crop communities (cover crops for green manure and potato in the spring-summer period and winter wheat in the autumn) during the second year of crop rotation have a high agrotechnical effect for decreased weed density at the end of crop rotation. The value of qualitative similarity index, which compare weed communities at the beginning and the end of crop rotation accordance with observed weed species is higher (Sǿrensеn qualitative index=50%) than the quantitative value of index (Sǿrensеn quantitative index=31.2%).

Ключови думи: crop rotation; organic management; structure of weed community; weed infestation

Дата на публикуване: 2018-07-12