Potential and Persistence of the Inhibitory Effect of Sorghum on Weeds

Potencial e Persistência do Efeito Inibitório do Sorgo sobre Plantas Daninhas

ABSTRACT:

The inhibitory interaction between plants may be an important strategy of integrated weed management (IWM). This study aimed to investigate the inhibitory effects of sorghum on phytosociology and infestation of weeds during cultivation and after harvest. An experiment was carried out in the field in a randomized block design in a split-plot arrangement. Plots consisted of sorghum and corn (control) and subplots were composed of different periods of weed community assessment after crop harvest (DAH) (0, 20, 40, 60, and 80 days). An increased number of species and botanical families was observed after harvest. Degradation of sorghum and corn straw reached the stabilization at 60 DAH. Although sorghum has presented a lower amount of straw and soil cover, weed infestation was, on average, 30% lower in relation to areas cultivated with corn. Sorghum showed an inhibitory effect on some weed species, influencing phytosociology, especially during the first 40 DAH, and can be used as part of IWM strategy.

Keywords:
allelopathy; herbicides; weed management; Sorghum bicolor; Zea mays