Perspectives of the breeding of tomato hybridcultivars carrying rin (ripening inhibiting) gene.II. Specific characteristics of the fruits of tomato rin gene hybrids

摘要

The heterosis effct of the rin gene on the specific character-istics of tomato fruit ripening and shelf life in Fl hybrids and the possibilityto obtain fruits with optimum combination between long shelf life and highfruit quality were investigated. The data presented reveal that the rin geneinhibits fruit ripening and softening, it reduces the typical fruit red colorintensity, increases fruit shelf life and affects negatively the flavor qualityof the tomato production. The inheritance of fruit coloring in Fl tomato hy-brids with rin gene in heterozygous state (rin/+) is incompletely dominantto the wild type tomato lines (+/+); the inheritance of fruit shelf life is inter-mediary to slightly incompletely dominant to the tomato lines with a ringene in homozygous state (rin/rin); the inheritance of polygalacturonaseactivity and the content of pectins and cellulose in the fruits is intermediaryto incompletely dominant to the lines with rin gene in homozygous state.Polygalacturonase activity in the fruits is in inverse correlation to fruit shelflife. Evidence is presented suggesting that comprehensive and purposefulbreeding accompanied by correct and precise selection of proper parentalcomponents, may yield Fl hybrid rin gene carrying tomato cultivars pos-sessing optimum combination of long shelf life and high fruit quality. Theimplicit necessity of genetic engineering approaches allowing breeding oftomato cultivars of the above described type is outlined.