Herbicide resistance and other weed management problems in citrus orchards

Weeds are one of the most important problems reducing the yield in citrus orchards. Despite all the weed control, the coverage of weeds can reach up to 50%. Horse-weed (Conyza canadensis), johnsongrass (Sorghum halepense), nutgrass (Cyperus rotundus), bermudagrass (Cynodon dactylon), sterile wild oat (Avena sterilis), bindweed (Convolvulus arvensis), wild mustard (Sinapis arvensis), barnyard grass (Echinochloa colona), lambsquarters (Chenopodium album) and palmer amaranth (Amaranthus palmeri) were the main harmful and potential harmful weed species. The most common methods used to manage weeds including herbicide applications, hoeing and mowing in Çukurova. As a result of increasing use of glyphosate herbicide for controlling weeds, glyphosate-resistant weeds such as horse-weed increased. Hoeing causes in increase in population of perennial weeds pecies. As a result of research, the best methods controlling weeds was mowing and cover crop applications. On the other hand, while irrigation increases weeding, water like weeds dominate in the orchards. Fresh animal manure carries seeds of various weed species including invasive ones such as palmer amarant. With global climate changes, incorrect timing and control methods against weeds cause to increase indicator species population. As a result, in order to provide successful and sustainable weed control in citrus orchards, integrated weed management must be used. The weed population must be followed and maintained under the economic threshold level. After using alternative management methods, herbicide rotation must be applied in correct time and recommended doses.