Genes from wild species for the improvement of yield and quality of processing tomatoes

Over the past 20 years replicated field trials of processing tomatoes have been conducted in California and Israel with the objective of identifying superior varieties. Analysis of the results indicate an average genetic gain for yield of 0.4%/yr for Israel and 1.5%/yr for California. No significant genetic gain in degrees brix was found for California, whereas for Israel, an average increase of 0.5%/yr was recorded. These improvements are partially due to the increase in the proportion of hybrids from the mid 1980's. The main reason for this relatively slow rate of progress, particularly for degrees brix, sterns from the lack of genetic variability for the trait in processing tomato germplasm. Using the molecular linkage map of tomato in conjunction with novel population structures, we have identified quantitative trait loci (QTLS) from five Lycopersicon species that improve key traits of processing tomatoes including degrees brix, by 10-20 percent. We expect that this novel variation will have an impact on future processing tomato varieties.