AGROINOCULATION METHODS TO SCREEN WILD LYCOPERSICON FOR RESISTANCE TO TOMATO YELLOW LEAF CURL VIRUS
B. Picó, M. Ferriol, M.J. Díez, F.N. Viñals
The effectiveness of agroinoculation techniques for causing systemic infection by TYLCV in different wild and cultivated Lycopersicon was determined. Rubagroinoculation of leaves, increased the effectiveness of sap-transmission reported previously, but resulted in an erratic and mild infection that did not discriminate among genotypes with different resistance levels. Stem agroinoculation was more effective, and 100% was obtained in the susceptible control. It can be used in breeding programmes as complementary to inoculation using Bemisia tabaci. Both techniques of inoculation provide a precise characterization of the resistance mechanisms in each genotype. Partial resistance to the virus along with resistance to the vector were found in L. hirsutum LA 1777 and L. pimpinellifolium hirsute INRA. The highest levels of virus resistance were observed in three L. chilense accessions (LA 1969, LA 1938, LA 1932). Resistance derived from LA 1932 remained after its introgression into cultivated tomato, giving breeding lines that were highly resistant to TYLCV.