Correlations between symptoms and DAS-ELISA values in two sources of resistance against tomato spotted wilt virus

The commercial tomato, Lycopersicon esculentum, cultivars Angela Gigante I- 5100 and Santa Clara (tospovirus susceptible), the Stevens cultivar, lines and experimental hybrids (tospovirus resistant), were used: a) to evaluate two sources of resistance to tospoviruses in tomato tone from L. esculentum /Rey de Los Tempranos, and another one from L. peruvianum/Stevens); and b) to verify statistically significant correlation between virus concentration determined through DAS-ELISA and symptomatology. In the Angela Gigante I-5 100 and the Santa Clara cultivars, the correlation coefficient was highly s ignificant and the symptom average level was high, showing that in suscepti ble cultivars the symptom evolution is related to the virus multiplication in the plant. As for the TOM 547 and TOM 556 lines (background of Angela Gi gante I-5100 and Santa Clara, respectively), there was no statistical corre lation between the symptoms and the viral particle concentration. Plants wi th light virus symptoms showed high absorbance values. Consequently we may assume that the resistance with 'Rey de Los Tempranos' background may be of the tolerant kind because the high virus concentration found does not nece ssarily relate to a high level of symptoms. In the lines BPX320E 3902-01, B PX320E 3905 and BPX320F 7902 (both with Santa Clara background) only few pl ants showed symptoms, which can be explained by incomplete penetrance of Sw -5 gene. In the case of non-symptomatic plants, the diagnosis using DAS-ELI SA revealed negative results. That outcome indicates that in some materials , where resistance is obtained from L. peruvianum, the virus multiplication in the tissues seemed not be present.