Bioefficacy of tank mixed post-emergence herbicides for weed control in forage maize (Zea mays L.)

A field trial was conducted to test the bioefficacy of tank mixed post-emergence herbicides for controlling weeds in forage maize (Zea mays L.) at Agronomic Research Area, University of Agriculture, Faisalabad. The treatments were: helosulfuron @ 40 g a.i. per ha + carfentrazone-ethyl @ 109 a.i. per ha, helosulfuron @ 40 g a.i. per ha + atrazine @ 296 g a.i. per ha and helosulfuron @ 40 g a.i. per ha + bromoxynil + MCPA @ 750 g a.i. per ha. Weedy check (control) and hand weeding treatment was also included for comparison. The experiment was conducted with four replications in Randomized Complete Block Design. Net plot size of 6.0 m x 1.2 m was maintained. Maize synthetic variety Pak-afgoyee was sown in the month of July, 2013. The data regarding weeds, and yield components of forage maize was recorded using standard procedures and was analyzed statistically by applying Fisher's analysis of variance technique. Treatment means were compared using the least significant difference (LSD) test at 5 % probability level. The lowest total weed density (25.50 m-2 15 DAT and 22.00 m-2 at harvest) was recorded in plots treated with tank mixed application of helosulfuron @ 40 g a.i. per ha + bromoxynil + MCPA @ 750 g a.i. per ha. Tank mixed application of helosulfuron @ 40 g a.i. per ha + carfentrazone-ethyl @ 10 g a.i. per ha gave maximum (74.47 %) control of C. arvensis at harvest. While minimum density (9.5 m-2) of E. colona was noted in those plots where foliar application of helosulfuron @ 40 g a.i. per ha + atrazine @ 296 g a.i. per ha was made. The highest values of plant population (22.00 m-2), plant height (230.00 cm), stem diameter (1.4 cm) of maize plant, number of green leaves (11.70) per plant and forage yield (80.06 t per ha) of maize was recorded with the foliar application of helosulfuron @ 40 g a.i. per ha + bromoxynil + MCPA @ 750 g a.i. per ha. It was observed that post-emergence application of helosulfuron @ 40 g a.i. per ha bromoxynil + MCP A @ 750 g a.i. per ha performed best and gave maximum control of weeds and increase forage yield of maize.