Weed Management In Solanaceous Crops In The Dominican Republic

A technological summary on the current weed control practices in soianaceous crops (processing and fresh tomato, peppers, eggplant, potato and tobacco) in the Dominican Republic was compiled based on information supplied by state agencies, private agrochemical companies and growers. According to the data collected, weed management systems integrating chemical and physical (cultivation and hoeing) practices are predominant in processing tomato and potato, whereas cultivation and hoeing are more common in fresh tomato, eggplant, peppers and tobacco. The cost of weed management as a percentage of the total crop production cost averaged 5-10% for potato, 7-15% for peppers, 10-13% for fresh tomato, 10-14% for tobacco, 12% for processing tomato and 15-20% for eggplant. Weed species associated with these crops were abundant, the most troublesome species were: Cyperus rotundus, Parthenium hysterophorus and several grass species in eggplant, processing and fresh tomato; Cyperus rotundus, Sida acuta, Parthenium hysterophorus and grass species in peppers; Cynodon dactylon, Cyperus esculentus and Cyperus rotundus in potato; Amaranthus spp., Chôme viscosa and several grass species in tobacco. The most commonly used herbicides are metribuzin and fluazifop-buthyl in tomatoes, fluazifop-buthyl in peppers and eggplant, linuron, metolachlor, paraquat and ametryn in potato. Herbicide utilization in tobacco is not significant. The number of cultivations and/or hoeings ranged from 1 to 4, depending on the crop species and the early use of herbicides. Yield losses due to weed interference under field conditions is estimated to be 25-35% in eggplant and tobacco, 25-50% in potato, 30-40% in processing and fresh tomato, and 40-50% in peppers.