The weeds in onion and their control

The protection of onions from the weeds and their negative impact in the field production is one of the most important measures. The onion is exceptionally succeptible to the weeds, especially in the first phases of the growth, considering the weak initial growth of the crop in comparison with the weeds. The seasonal dynamics of the onion weeds is not so noticeable like with the other crops, while the weeds that appear most frequently are: Amaranthus blitoides, Ambrosia artemisiifolia, Chenopodium album, Cirsium arvense, Convolvulus arvensis, Cynodon dactylon, Datura stramonium, Portulaca oleracea, Setaria glauca and Stellaria media. The chemical control measures mean the herbicide use before or after the emergence of the crop and the weeds. Before the emergence the herbicides based on aclonifen and pendimethaline can be used, while after the emergence herbicides based on fluroxypir, clopyralid, fluazifop-P-butyl, clethodim, quizalofop-P-ethyl, quizalofop-P-tefuryl and propaquizafop are used.