In Vitro Radiation Induced Mutagenesis in Potato

Abstract

Type and frequency of radiation induced variation for upgrading potato cultivars was investigated. Cultivars Cara, Red Cara, Kerrs Pink and Record were cultured on modified Murashige & Skoog’s medium and irradiated with 2000 r gamma rays. Shoots of the irradiated and control cultures were cut into single nodes and subcultured. The proliferated stems were recultured from pieces with 2 to 4 nodes which after 6 months produced micro-tubers ca. 2 to 8 mm diameter. Of the 2450 micro-tubers harvested, 1500 were sprouted and transplanted in soil under plastic. Of these, 1085 micro-tubers produced plants, and gave 11945 macro-tubers which were scored for variation in tuber skin and eye colour, skin texture, tuber shape and eye-depth. In ‘Cara’, 4.8% progenies showed mutation from red-eye to white-eyes. In ‘Red Cara’, 4.2% progenies mutated from red to white skin with red or white eyes. In ‘Kerrs Pink’, 5.3% plants had pale cream skin color instead of pink skin, 1.4% had very light pink skin and 5.0% had eyes shallower than the parental cultivar. In ‘Record’, 9.4% plants had tubers with pale light skin. Infrequently, variation in tuber shape was observed in all the cultivars. The range and frequency of observed variation suggested that in-vitro radiation is a suitable technique to upgrade potato cultivars for specific characters.