低温干燥贮藏包衣和非包衣玉米种子活力及生理差异性研究

以玉米品种NK618和济单7号的包衣和非包衣种子为试验材料,低温干燥贮藏16个月、28个月和40个月,分别测定种子的发芽、活力指标,测定幼苗的SOD、POD、CAT、MDA、脯氨酸等含量,探讨低温干燥贮藏条件下玉米种子的可种用时间,比较包衣和非包衣玉米种子间的贮藏差异性及生理变化。结果表明,低温干燥条件下玉米种子贮藏16个月,包衣种子的各项发芽及活力指标比新种子显著降低,非包衣则无显著性变化;贮藏28个月,NK618和济单7号非包衣种子的发芽率分别是91%和87%,均可作种用,包衣种子已无种用价值;贮藏40个月时包衣和非包衣种子均不可作种用。包衣种子比非包衣种子更易老化,幼苗的SOD、POD、CAT含量均随贮藏时间延长而降低,贮藏28个月两个品种包衣和非包衣3种酶含量均比对照新种子含量降低,但差异显著性不同;MDA和脯氨酸含量随贮藏时间延长而增加,贮藏40个月时两个品种的包衣和非包衣种子萌发幼苗MDA含量均达最大值。

Difference of Vigor and Physiology between Coating Seeds and Non-coating Seeds of Maize Stored under Low Temperature and Low Humidity Environment

In order to study the tolerance time used as sowing seeds under low temperature and low humidity conditions of storing and the difference between the coating and non-coating seeds of storage and physiology change, coating and non-coating seeds of two maize varieties NK618 and Jidan 7 were selected as experimental materials, the germination and vigor of seeds were tested when stored at low temperature and low humidity environment for 16 months, 28 months, and 40 months; and the contents of SOD, POD, CAT, MDA, and proline in seedlings were measured. The results showed that maize seeds were stored under low temperature and low humidity conditions for 16 months, the germination and vigor index of the coating seeds decreased significantly than the contrast seeds, but it showed no significant difference; when stored for 28 months, the germination rate of non-coating seeds of NK618 and Jidan7 were 91% and 87%, respectively, and could be used for sowing, but the coating seeds had no sowing value. All seeds stored for 40 months had no seed value. Coating seeds were easily aged than non-coated seeds. The contents of SOD, POD, and CAT in germinating seedlings all decreased along with extending of storage time. By 28 months, the contents of three protective enzymes were lower than those of the contrast new seeds, but the difference significance was different. The contents of MDA and proline increased along with extending of storage time. Germination and vitality index were more sensitive to age than the physiological index. By 40 months, the MDA content of the seedlings from the coating and non-coating seeds of two maize varieties was the maximum.