γ射线外照射影响粳稻生育的初步研究

EFFECT OF ^(60)Coγ-RAY ON GROWTH AND DEVELOPMENT OF RICE

用^(60)Coγ射线外照射粳稻生长植株(1、2、3、4、5、6片叶、孕键、抽穗和开花期),每个时期所用照射量为2、5、10、15、20、25kR,照射量率为96.8—99.1R/min。试验表明:1—6片叶接受^(60)Coγ射线照射的植株,辐射生理损伤具有阶段性,照射后新长出的3片叶是辐射损伤最为明显的部位,通过照射后的株高增长曲线,可粗略预报辐照后减产10％、50％、90％的植株。水稻一生中孕穗期是对γ辐射最为敏感的时期,5kR便可减产80％,10kR减产100％。

Japonica rice plants were irradiated by 60Co γ-ray at the first,second,third,fourth,fifth,sixth leaf,booting,heading and blooming stages.2,5,10,15,20 and 25kR were used for each stage.Experimental results showed that radiation damage occured from the stages of first leaf to the sixth leaf.It was found that the three new leaves which grew after irradiation suffered the most obvious damage.The plants which would reduce yields by 10%,50%,90% because of irradiation could be predicted according to their height increase curve.Booting stage of rice was the most sensitive stage to γ-ray irradiation and if rice was irradiated at that stage,5kR could reduce the yield by 80%,while 10kR could reduce the yield by 100%.