Study on the effect of γ-irradiation (Co-60) on seed germination and agronomic traits in tomato plants (Lycopersicon esculentum L.)

Abstract

Mutagenesis is an important technique for creating novel mutants having improved agronomic traits. In this study, LD50 was determined at 807 Gy depending on the germination percentage of tomato seeds irradiated with cobalt-60, using absorbed gray (Gy) dose of 50, 100, 150, 200, 250, 500, and 1000 Gy with control. GR30 and GR50 values were 214 and 502 Gy based on the regression formula on seedling length. Though LD50 is important, the dose range between 214(GR30) and 502(GR50) is more functional to get desirable mutation as the survival of the mutants is more important than germination. The variation was observed in all of the agronomical traits among the treatments. Most of the morphological traits were found better at 250 Gy in comparison with the control and the value decreased sharply at higher doses followed. The highest weight of single fruit was 145.33 g recorded at 250 Gy while the lowest was 70.67 g noted at 500 Gy. The highest fruit yield per plant was 1270 gm obtained at 250 Gy and the lowest was 800 gm found at 500 Gy. Shelf life was found better (34 days) at the 250 Gy dose level and the lowest was 6 days got in the control treatments.

Keywords

• BARI tomato-8
• GR50
• irradiation
• LD50
• mutation breeding
• shelf life