THE STUDY OF THE IRRADIATION EFFECT ON RUNNER PLANTS OF STRAWBERRY WITH ⁶⁰CO-GAMMA RAY

The runner plants of five strawberry varieties were irradiated by three different doses of ⁶⁰Co-gamma ray, and the irradiation effect of lethality, lesion, growth restraint on runner plants and the production of new runners was studied. The results indicated there was the dead runner plant in five strawberry varieties treated by ⁶⁰Co-gamma ray within 30-80 Gy. The death rate was between 22% and 88.7%, which raised with increase in the dose of ⁶⁰Co-gamma ray, but there were different death rates from the different varieties. There happened abnormal leaves in all treatment compared with control. The change of the length and width of leaf, the height and size of plant was different with irradiation dosage and strawberry variety. The occurence rate and the quantity of the new runners decreased significantly. The different varieties had different sensitivity to the irradiation of ⁶⁰Co-gamma ray, the most sensitive variety was ‘Akihime’, the second was ‘Hokowase’, ‘Chun Xu’ and ‘Sheng Xing’, ‘Shuo Feng’ was most insensitive. The half lethal dose of irradiation to ‘Akihime’ responded to between 30 Gy and 50 Gy, to ‘Hokowase’, ‘Chun Xu’ and ‘Sheng Xing’ between 50 Gy and 80 Gy, to ‘Shuo Feng’ above 80 Gy.