Tomato yellow leaf curl virus (TYLCV) causes one of the most devastating emerging diseases of tomato worldwide (Czosnek, 2007). The virus (genus Begomovirus, family Geminiviridae) is transmitted by the whitefly Bemisia tabaci. From the early 1960s, TYLCV has quickly spread from the Eastern Mediterranean Basin to the entire Middle East, CentralAsia, North and West Africa, southeastern Europe, the Caribbean islands, southeastern USA, Mexico,the Southern Indian Ocean islands and Japan (Lefeuvre et al.,2010).In severely affected regions, crops may be totally lost (Picó et al., 1996).The tremendous economic impact of TYLCV and the swift spread of TYLCV disease worldwide have triggered a large body of research tackling many aspects of the viral disease over the last 30 years: molecular biology, plant–virus–vector relationship, epidemiology, disease management and breeding for resistance.
The rapid spread of the viral disease is caused by whitefly pressure and by high transmission efficacy. A single whitefly is able to inoculate a plant following a 15-min acquisition period and a 15-min inoculation period. In the field, inoculation can occur immediately after transplantation. Infected seedlings will remain stunted and will not yield fruits. Apart from whiteflies,TYLCV can be transmitted by grafting, by agroinoculation and by DNA-coated particle bombardment. It is not seed transmitted. The relationships between begomoviruses and whiteflies are complex. TYLCV is transmitted by B. tabaci in a circulative manner.
TYLCV and some related viruses influence several features of insect pathogens: they affect B. tabaci longevity and fertility and are sometimes transovarially transmitted; they affect the whitefly transcriptome, activating the expression of genes related to the whitefly immune response (Luan et al., 2011)
by KAREN-BETH G. SCHOLTHOF, SCOTT ADKINS , HENRYK CZOSNEK , PETER PALUKAITIS,
EMMANUEL JACQUOT , THOMAS HOHN , BARBARA HOHN , KEITH SAUNDERS,
THIERRY CANDRESSE, PAUL AHLQUIST , CYNTHIA HEMENWAY AND GARY D. FOSTER
control plant virus with Lin chemical Lentinan