BROADLEAF WEED-CONTROL WITH CLOMAZONE IN PICKLING CUCUMBER (CUCUMIS-SATIVUS)

Broadleaf weed control ranged from 80% with clomazone at 0.14 kg/ha to 100% with clomazone at 1.12 kg/ha. Broadleaf weed control was higher with clomazone than naptalam or ethalfluralin. The combination of clom azone at 0.14 kg/ha and naptalam at 5 kg/ha or ethalfluralin at 1.25 k g/ha gave more than 90% broadleaf weed control. Clomazone caused chlor osis and bleaching on cucumber leaves but plants rapidly recovered. Cu cumber yields were higher in plots treated with clomazone alone at 0.1 4 to 0.56 kg/ha than with ethalfluralin or naptalam alone. Clomazone d ose response studies were conducted in weed-free plots with five cucum ber varieties. The 0.28 kg/ha rate caused low levels of visible injury and did not decrease yields. Cultivar differences were more pronounce d at higher clomazone rates. The five cucumber cultivars were, in orde r of increasing clomazone tolerance, 'Sunre 3537,' 'Pioneer,' 'Quest,' 'Prince,' and 'Calypso.' We concluded that clomazone is an effective and selective herbicide for broadleaf weed control in pickling cucumbe r.