Identification of Resistance to Tomato Spotted Wilt Virus in Lettuce. M. Wang, Department of Plant Pathology, University of Hawaii, Honolulu 96822. J. J. Cho, R. Provvidenti, and J. S. Hu. Department of Plant Pathology, University of Hawaii, Honolulu 96822; Department of Plant Pathology, Cornell University, New York State Agricultural Experiment Station, Geneva 14456; and Department of Plant Pathology, University of Hawaii, Honolulu 96822. Plant Dis. 76:642. Accepted for publication 14 January 1992. Copyright 1992 The American Phytopathological Society. DOI: 10.1094/PD-76-0642D.
The progenies of an interspecific cross between Lactuca sativa L.
and L. saligna L. originating from the Institute of Field and Garden
Crops ARO, Israel, were screened for resistance to tomato spotted
wilt virus (TSWV) in greenhouses. Plants from 130 lines of this cross
were tested by mechanical inoculations for sensitivity to a TSWVL
strain isolated from lettuce in Maui, Hawaii. Of the 4,489 plants
inoculated, only 192 from 42 lines survived virus infection and grew
to maturity. Enzyme-linked immunosorbent assay (1) was used to
test for TSWV in TSWV-inoculated leaves and newly developed leaves
of survivors at the flowering stage and before harvest. After inoculations
of the resistant accessions in which the majority of plants survived,
TSWV was detected in the inoculated leaves but not in new growth.
Additional testing confirmed the resistance of the surviving progenies.
Breeding with the resistant lines and commercial susceptible lettuce
cultivars is under way.