【摘要】 在同一品种的辐射M₂代中,一般可同时出现早、晚双向熟期的突变,且后者的突变率高于前者分别为1.39％和2.67％。突变体提早和延迟的天数两者基本接近（11.5d对10.3d）。早晚双向突变体,由于其熟期发生了相反方向的改变,因而在一定程度上株高、每穗粒数、千粒重等农艺性状也发生了双向变异,且达到显著水平。更多还原

【Abstract】 The dry rice seeds were radiated with same dosage of ⁶⁰Co-γ rays. In its M₂ generation, there appeared early and late mutant plants. The rates of early and late mutants were 1.39％ and 2.62％, respectively. In early type of varieties, the rate of early mutants was lower than that of late ones （0.91％ vs 3.54）; In late type of varieties, the rates of early and late mutants were generally same （1.71％ vs 1.98％）. The early and late mutants changed in some extent the agronomical traits such as plant height and panical length. The correlation between growing period length and expression of the traits was not consistent in early and late mutants. The early and late mutants had some bad effects on these traits.更多还原