Tomato (Solanum lycopersicum L.) is widely grown in the tropics but production is subject to high losses
from diseases. AVRDC—The World Vegetable Center initiated a program to develop fresh market tomato
lines resistant to begomoviruses causing tomato yellow leaf curl disease, Phytophthora infestans causing
late blight, Ralstonia solanacearum causing bacterial wilt, Stemphyllium spp. causing gray leaf spot, Fusarium
oxysporum f. sp. lycopersici race 2, and Tobacco mosaic virus. This work provides greenhouse, field,
molecular marker, and laboratory protocols used in the screening and selection process that were applied
to segregating populations during generation advance over three years to develop five multiple disease
resistant F7 fresh market tomato lines. Resistance of the five lines to the abovementioned diseases was
confirmed in subsequent evaluations. Average yields of the five lines exceeded 100 t/ha under optimal
temperatures in a dry season trial, but yields were reduced in a second trial under higher temperatures
and rainfall. Seed of three multiple disease resistant F7:8 lines is available from AVRDC (http://avrdc.
org/seed/improved-lines/); these lines have potential for release as inbred line cultivars, hybrid parental
lines, or breeding stock.