Mutation of good quality small tetraploid watermelon and its main characteristics

Treatments of seed soaking,dripping plantlets with 0.2% and 0.4% colchicines were conducted on good quality small diploid watermelon such as 64-2-6-4-1.The results showed that the mutation rate of the tetraploid watermelon reached 11.6%～14.1% by dripping the plantlets after picking-off the young leaves surround the growth tip with 0.2% colchicines,which was 10.0% higher than the normal treatments.After treating the small tetraploid watermelon of mutation with hybridization,backcrossing,systematic isolation and screening in different gene types,the variety lines such as B154 and XH4 were selected,which showed prominent comprehensive characteristics of early mature,good quality and long shelf/transport life.