Viral diseases causing the greatest economic losses to the tomato crop .2. The Tomato yellow leaf curl virus - A review

Tomato yellow leaf curl geminivirus (TYLCV), transmitted by the whitefly Bemisia tabaci (Gennadius) is one of the most devastating diseases of cultivated tomato (Lycopersicon esculentum Mill.). TYLCV causes economic losses up to 100% in tomato crop in many tropical and subtropical regions, and is spreading towards new areas. The increasing economic importance of TYLCV has resulted in the need for accurate detection and identification procedures, stimulating intensive research efforts focused on virus biology, diversity, and epidemiology to develop successful control strategies. Breeding for resistance appears to be the best approach to control this disease, but to date only partially resistant hybrids are commercially available. Search for new sources of disease resistance needs to be intensified. The purpose of this paper is to collect and summarize all these efforts, offering an updated review of these new approaches on virus transmission, molecular biology, variability, diagnostic methods, and potential ways to control. This will lead to a better understanding of the virus-vector-host relationships, key factors in the adoption of disease control measures.