PRE-EMERGENCE WEED CHEMICAL CONTROL IN HUSK TOMATO

The objectives of this study were to evaluate the phytotoxic effect of several pre-emergence herbicides on husk tomato and their weed control ability in Irapuato, Guanajuato, Mexico. The experiment was carried out from March to June 2008. The herbicide treatments were pendimethalin, flufenacet, bensulide, linuron, rimsulfuron, trifluralin, isoxaflutole, metribuzin, and prometryn, at rates of 1650, 900, 5760, 1000, 50, 1500, 52.5, 240 and 480 gia/ha, respectively. Two control treatments, a weedy one (untreated) and a hand-weeded one, were included in the experiment. A randomized block design with four replications was used to set up the experiment, and its statistical analysis was carried out. The means were separated by using the Tukey test P <= 0.05. The results indicate that the most abundant weeds were barnyard grass (Echinochloa cruss-galli (L) P. Beauv.), curly dock (Rumex crispus L.) and jungle rice grass (E. colonum (L.) Link). Bensulide, rimsulfuron and trifluralin had the lowest levels of phytotoxicity to the crop, with 3.2, 7.5 and 7.5%, respectively. In contrast, pendimethalin, prometryn and flufenacet caused the greatest damage to the husk tomato crop, with 90.75, 43.75 and 31.25%, respectively. Rimsulfuron and linuron depicted the best weed control; with 98 and 70%.