Developing new parthenocarpic tomato breeding lines carrying iaa9-3 mutation

A number of different strategies have been utilized to introduce parthenocarpy into tomato commercial cultivars. In this study, we evaluated three segregating populations (F 2 , F 3 , and F 4 ) derived from conventional crossing between iaa9-3 mutant in Micro-Tom and an inbred pure tomato line V62. The mutation caused potato leaf style and high parthenocarpic fruit set ratio (nearly 90%). Introducing iaa9-3 mutation into tomato cultivar has some advantages over other parthenocarpic mutants, including, (1) retaining the normal stamen structure and fertile pollen; (2) the parthenocarpic lines can produce sufficient seeds for self-pollinated propagation; (3) average seedless fruit weight of experimental lines ranged from 25 g/fruit (small category) to over 50 g/fruit (intermediate category), together with good number of fruits/plant which can lead to a theoretical seedless fruit yield of over 3000 g/plant, which is acceptable for commercial varieties; (4) increasing the quality of seedless fruits compared to seeded fruits which is attributable to an increase in the mass of placental area and a higher Brix level than locule and pericarp areas. The selected iaa9-3 mutant lines should be used to develop the tomato parthenocarpic varieties with high seedless fruit yields and quality.