Fruit of tomato (Lycopersicon esculentum Mill.) hybrids heterozygous for the alc ripening mutation stored on average 60% (3.6 days) longer at 20C than that of their normal-ripening parents. There were no detrimental effects of the alc heterozygous condition on fruit color, firmness, or size. The background into which alc was introduced also affected fruit quality and shelf life. These results indicate hybrids heterozygous for the alc ripening mutant can produce commercially acceptable fruit with significantly longer shelf life than their normal-ripening parents.
Martha A. Mutschler, David W. Wolfe, Edward D. Cobb and Kenneth S. Yourstone
Martha A. Mutschler, Edward D. Cobb, Barbara E. Liedl and Joseph A. Shapiro
Acylsugar mediates the resistance of Lycopersicon pennellii LA716 to several important insect pests of cultivated tomato, including potato aphid, green peach aphid, leaf miner, fruitworm, armyworm, and silverleaf whitefly. Incorporation of acylsugar-mediated multiple pest resistance could result in a significant reduction in the use of pesticidal sprays in cultivated tomato. Development of a reliable assay for acylsugar production and confirmation of the association between the resistance and acylsugars allowed us to try to breed for the trait by selecting for acylsugar-producing plants. The breeding cycle allows us to progress by one backcross generation per year. The breeding program was faced by several challenges, including interference in gene transfer by interspecific crossing barriers, and the oligogenic nature of the acylsugar-mediated resistance trait. Despite these challenges, the breeding program has produced BC3F2 plants that produce effective levels of acylsugars, are tomato-like in vine appearance, and produce seed-bearing fruit in the field without manual pollination. The current status of the program and future plans will be discussed.