Journal of Agricultural Science; Vol. 8, No. 4; 2016 ISSN 1916-9752 E-ISSN 1916-9760 Published by Canadian Center of Science and Education 84 Seedlessness and Fruit Quality Traits of Gibberellin Induced Parthenocarpic Fruit in Seven Tomato Genotypes (Solanum lycopersicum L.) Agus Budi Setiawan 1 , Rudi Hari Murti 2 & Aziz Purwantoro 2 1 Faculty of Agriculture, Gadjah Mada University, Yogyakarta, Indonesia 2 Genetics and Plant Breeding Laboratory, Faculty of Agriculture, Gadjah Mada University, Yogyakarta, Indonesia Correspondence: Rudi Hari Murti, Genetics and Plant Breeding Laboratory, Faculty of Agriculture, Gadjah Mada University, Jalan Flora Bulaksumur Yogyakarta 55281, Indonesia. Tel: 62-274-563-062. E-mail: rhmurti@ugm.ac.id Received: December 3, 2015 Accepted: January 28, 2016 Online Published: March 15, 2016 doi:10.5539/jas.v8n4p84 URL: http://dx.doi.org/10.5539/jas.v8n4p84 Abstract Parthenocarpic fruit development is regulated by a plant hormone, i.e. gibberellin. The response of seven lines of tomato to gibberellin was investigated to distinguish the degree of parthenocarpy and to compare the quality of seedless and seeded fruits. The flower from stage 12 (size 5 mm) until 4 days after anthesis was sprayed with GA 3 0 mmol/L and 0.06 mmol/L. The treatments were arranged in Randomized Complete Block Design with three replications. GA 3 0.06 mmol/L reduced pollen germination, whose pollen germination (28.98%) was lower than 0 mmol/L (46.06%). The total numbers of seeds and fertilized seeds of treated fruit were significantly reduced in comparison with the control. Gibberellin application also increased the number of degenerated seeds. Within the genotypes studied, four groups were distinguished, which showed a different degree of parthenocarpy in response to gibberellin application. Kaliurang 206 and A65 are categorized as seedless with a 93.65% and 89.58% reduction in the total number of seeds, respectively. Gamato 1 is categorized as low-seeded with an 83.83% reduction in the total number of seeds. Gamato 3, Gamato 5, and B78 are categorized as medium-seeded with a 69.83-80.85% reduction in the total number of seeds, whereas A175 is categorized as normal-seeded with a 36.94% reduction in the total number of seeds. Gibberellin significantly increased the sugar content by 14.04% and reduced the ascorbic acid content by 9.68% of parthenocarpic fruits compared with the untreated. Keywords: fruit morphology, genotype response, plant growth regulator, seed formation, seedless fruit 1. Introduction The majority of seeds are undesirable features in many crops, particularly edible fruit. Some seeds have a bitter taste, are hard, and cause a digestive problem. Seeds and their cavities could be replaced by edible fruit tissue and it is more desirable than seeded fruit. Seedless fruits are developed from unfertilized ovary due to the absence of pollination and/or fertilization, and they are therefore called parthenocarpy (Varoquaux, Blanvillain, Delseny, & Gallois, 2000). Parthenocarpy is a useful trait for industrial purposes, especially the tomato sauce industry because seeds should be removed before processing in order to obtain the best quality of the sauce (Rotino et al., 2005; Sato, Peet, & Gardner, 2004). In addition, parthenocarpy may improve the quality of the fruit through the increased sugar content of the fruit (1°Brix higher than normal fruits), high dry matter content, less acidity, less cellulose, and higher contents of carotene and lycopene than seeded fruit (Lukyanenko, 1991). Several methods have been proven to produce seedless fruits such as triploid tomato (Kaganzur, Mizrahi, Zamir, & Navot, 1991). Recently, the parthenocarpic transgenic tomato was obtained either by the regulation of auxin synthesis (DefH9-RI-iaaM) (Rotino et al., 2005), rolB (Carmi, Salts, Dedicova, Shabtai, & Barg, 2003) or regulation of GA signaling repressor i.e. DELLA (Martí et al., 2007). However, those methods require more time and costs than breeding diploid cultivars of tomato. In order to resolve that problem, plant growth regulator can be used to induce parthenocarpy in tomatoes such as GA 3 (Serrani, Fos, Atarés, & García-Martínez, 2007) and auxin (Serrani, Ruiz-Rivero, Fos, & García-Martínez, 2008). GA 3 had also been widely used in grape (Jung et al., 2014b) and successfully induced parthenocarpic fruit.