Effect of γ-irradiation on in vitro pollen germination of muskmelon (Cucumis melo L.)

Induction of haploid plants in vegetable crops through airradiated pollen method is of utmost importance in contemporary vegetable breeding to accelerate the breeding cycle. But the major problem of this technique is the sensitivity of pollen grains to higher irradiation doses. Present work investigated the effect of different γ-irradiation dosage (250 to 400 Gy) on percent germination and tube length of pollen grains of muskmelon (Cucumis melo L.) genotype, MS-5 on Brewbakers medium. The observations were recorded after 1, 2 and 3 hours of incubation. Irradiated pollen didn’t show any sign of germination at 1 and 2 hours, however germination initiation was observed in the nonirradiated pollen. A decrease in percent germination and pollen tube growth was observed with incremental irradiation dose. Very little germination or abnormal pollen tube growth was recorded for pollen grains irradiated at 400 Gy. This study advocates the need for deriving out the appropriate a-irradiation dose specific for the muskmelon genotype besides obtaining the extent of the lethality for the irradiated pollen grains for its possible application in generation of haploids through parthenogenesis.