The Effect Of ⁶⁰Co-γ On Different Cultivars Pollen Of Peach And Apricot

In order to find the radiation effect difference among cultivars of peach and apricot and the change among pollen germination ratio of different cultivars, we chose 6 cultivars of peach and apricot to be radiated by 60Co-γ. The dose level were set at 20, 50, 150 and 300 Gy, and the dose ratio were 0.6,1.2,1.8GY/min. The main results were as follows:1 The damage 60Co-γof 20Gy with 0.6Gy/min dose ratio for peach'qiumihong'is not significant, but is very serious for apricot cultivar'hongfeng'. This treatment damaged the pollen of peach cultivar'qiumihong'and'qiutian'.However, it inhenced the pollen of peach'shuguang'. For the aricot cultivars, pollen of'hongfeng'and'jintaiyang'were damaged especailly'hongfeng', but'kaite'were inhenced.2 There are heavy effect of different dose ratio of 60Co-γon pollen germination of different cultivars of peach and apricot. For the peach cultivars, the germination ratio of pollen of'qiumihong'were higher after the treatment of 60Co-γat 1.8Gy/min, and it is lower after the treatment of 0.6, 1.2 Gy/min than dose level of 150 Gy radiation; The pollen germination of'qiutian'and'shuguang'were high after the treatment of 0.6Gy/min of 60Co-γ, but it is lower after the treatment of 1.8Gy/min and 50, 150 Gy of 60Co-γ.For the apricto cultivars, the pollen germination ratio of'hongfeng'and'kaite'which were radiated at the ratio of 1.8Gy/min were high, and it is lower after the 60Co-γtreatment of the other 3 dose ratio and 2 dose level of 20, 50 Gy. The germinatio ratio of'kaite'were lower at low dose level of 0.6, 1.2Gy/min and 50, 300Gy; the germination ratio of'jintaiyang'were significantly lower than control after the 60Co-γtreatment at 3 dose level and 300Gy, and it is higher at the dose ratio of 1.8Gy/min with dose levele of 20 and 150Gy, respecitively.3 There are differences among cultivars after different dose with the same dose ratio of 60Co-γtreatment. For the 0.6, 1.2 and 1.8 dose ratio, 20Gy radiation could get the high germination ratio on'qiumihong'and'qiutian', and 50Gy is good for'youtao'. The germination ratio of pollen of'hongfeng'and'kaite'apricot were high after the treatment of 300 and 20 Gy. However, for'jintaiyang', it is high at low dose of 20 and 50Gy with low dose ratio of 0.6 and 1.2 Gy/min. 4 These results indicated that the change rules of different cultivars of peach and apricot after the treatment of different dose ratio is different, but all the materials were recovered to the level control at the 14th day after radiation.