DIFFERENTIAL TOLERANCE OF PUMPKIN SPECIES TO BENTAZON, METRIBUZIN, TRIFLURALIN, AND OXYFLUORFEN

ABSTRACT Response of pumpkin species including Cucurbita pepo convar. Pepo, Cucurbita moschata Duch, Cucurbita pepo, Cucurbita maxima, and Lagenaria vulgaris to bentazon, trifluralin, metribuzin, and oxyfluorfen was evaluated in Outdoor pot experiments in 2014 and 2015. Different postemergence doses (bentazon and oxyfluorfen) and preplant incorporated (metribuzin and trifluralin) herbicides were evaluted on pumpkin species at various growth stages. Results showed that the sensitivity of pumpkins species to applied herbicide varied greatly among tested species. On overall, dry weights of Cucurbita spp. were reduced by 12.50%, 48.60%, 23%, and 73.13% when pumpkin was treated with trifluralin, metribuzin, bentazon and oxyfluorfen, respectively. Pumpkin crops were not tolerant of metribuzin and oxyfluorfen and plants showed injures. Results indicated that trifluralin and bentazon have the potential for possible application in pumpkin particularly when broadleaf weeds are dominant.