Capacidade competitiva de losna-branca (Parthenium hysterophorus L.) com milho de primavera

In recent decades, allelopathy has gained considerable attention in sustainable agricultural systems. In the current situation, an attempt has been made to investigate the optimal competition period for weed control in maize. Experiments were designed in randomized complete block design and Parthenium hysterophorus was naturally infested in experimental plots during the spring season 2014 to determine the critical competition period for weed control in maize. The relations between grain yield and different competition durations were determined via regression analyses. The experiment comprised seven treatments viz, control treatment, competition for 30, 45, 60, 75, 90 and 105 days after emergence. The results suggested that a weedfree period (control treatment) of maize was enough to provide acceptable grain yield. Whole season different competition periods and weed-free plots were included in the experiment for yield comparison. The highest grain yield was obtained from plot kept weed-free (control treatment). The results clearly indicated that P. hysterophorus was competitively more aggressive and its control in maize crop provide maximum grain yield.