The Effects of Methyl Bromide Fumigation and Grafting on Yield and Root Diseases of Tomatoes

Abstract

SUMMARY Methyl‐bromide (1 lb/100 sq. ft), applied as in commercial practice, gave an increase in yield of both grafted and ungrafted tomato plants in glasshouse soils naturally‐infested with root diseases. Grafted plants greatly outyielded ungrafted plants on treated and untreated soil where phytophthora stem and root rot was present. The effect of the gas on corky root rot varied in the experiments and, on one nursery, control of the disease was not reflected by increased yield.

The relationship between brown and corky root rot caused by Pyrenochaeta lycopersici and yield loss in tomatoes established by the use of artificially infested soils

“…Although it is encouraging that under carefully controlled experimental conditions similar relationships between disease severity and yield loss can be obtained through the use of two very different techniques, there is evidence to suggest that soil conditions and other environmental factors can have a tnodifying effect on this realtionship. Upstone (1968) found that in one experiment, differences in severity of brown root rot were not reflected in yield, and Jeves & Smith (1980) found no signifieant yield effects resulting from disease differences following a number of fungicide treattnents. Ebben et at.…”

Tolerance of Tomatoes to Pyrenochaeta lycopersici: Comparison of a Tolerant Line with a Susceptible Cultivar in Infested Soils

“…As an alternative to soil sterilisation it is practicable to graft fruiting cultivars on to interspecific F^ hybrids tolerant to P. lycopersici. This method gives consistently good results (Smith and Proctor, 1965;Haine et a/., 1968;Upstone, 1968) but has not been widely adopted, probably because it is labour intensive for a short period in the spring and some loss of early yield occurs. To overcome these problenis plaDt breeders have transferred the tolerance from wild Lycopersicon species to L. esculentum cultivars.…”