REVIEW OF MAJOR CEREAL CROPS PRODUCTION LOSSES, QUALITY DETERIORATION OF GRAINS BY WEEDS AND ITS PREVENTION IN ETHIOPIA

Grain production plays a vital role in feeding an ever-increasing world population. Among grain crops that are serving as a food source, rice, wheat, maize, sorghum, and barley rank the most important ones. However, the production status of important cereals is highly reduced by intrinsic and extrinsic factors. Amongst these, weeds are key production constraints that reduce yield and deteriorate the quality of crops product. This paper was aimed to review studies that were conducted on the effect of weeds in crops production both on quantitative as well as qualitative losses. Weeds affect crops by competing for light, moisture, nutrients, and space, and produce seeds by suppressing crop plants faster. Crop yield losses are estimated at 10 to 90% depending on the crop type and area. On a crops basis, total losses are estimated about as high as 26–29%, 31%, 90%, 60%, 64% for wheat, maize, rice, sorghum, and barley, respectively if good weed control is not carried out. The negative impact of weeds on the quality of grains ultimately reduces the market value, nutritional status, and viability of the crop’s seeds. Therefore, it is crucial to managing weeds infestation through the application of integrated weed management strategies that can be cultural practices, use of herbicides, manual and mechanical weeding including a quarantine control system.