不同居群垂穗披碱草种子生理生化、营养特性与其萌发时滞的相关性

Correlation between physiological,biochemical, nutritional characteristics and germination delay of Elymus nutans seeds in different populations

摘要:

【目的】揭示影响垂穗披碱草种子萌发时滞的关键因素。【方法】对不同居群野生垂穗披碱草种子的萌发时滞、生理生化特性、内源营养物质含量及其环境因子进行差异比较。【结果】居群 P2 种子萌发时滞最短，为 6. 0 d，P8 萌发时滞最长，达到 47. 3 d。居群 P5 种子千粒重最大，为 4. 2 g，较千粒重最小居群 P6 高 82. 6%(P＜0. 05)。P8 种子的脯氨酸(Pro)含量和过氧化氢酶(CAT)活性最高，分别较最低的 P1 和 P4 提高了 517% 和 14. 2%(P＜0. 05)；P1 的丙二醛(MDA)含量最低，较 P7 降低了 34. 9% (P＜0. 05)，过氧化物酶(POD)活性和磷(P)含量最高，分别是 P5 和 P4 的 3 倍、4 倍(P＜0. 05)；P3 的电导率(Ec)值最低 ，较 P6 降低了 43. 1%，超氧化物歧化酶(SOD)活性最大 ，较 P2 提高 12. 8%(P＜ 0. 05)；P5 的可溶性糖和淀粉含量最高，分别较含量最低的 P6 和 P1 提高了 87%、110%(P＜0. 05)；P4 的 N 含量最高，较 P7 提高了 59. 6%(P＜0. 05)；P9 的 K 含量最高，较 P4 提高了 27. 2%(P＜0. 05)。 【结论】经相关性分析得出，萌发时滞与淀粉、MDA 含量及海拔高度呈正相关关系，其中萌发时滞与淀粉含量显著相关，即淀粉含量是影响种子萌发时滞的重要因素。

Abstract:

【Objective】 To reveal the key factors affecting the germination delay of Elymus nutans seeds. 【Method】 In this study，we compared the differences in germination delay，physiological and biochemical characteris‐ tics，endogenous nutrient content and environmental factors of wild Elymus nutans seeds from different populations. 【Result】 The results showed that population P2 had the shortest germination delay of 6. 0 d and P8 had the longest germination delay of 47. 3 d. Population P5 had the highest 1000‐seed weight of 4. 2 g，82. 6%(P＜0. 05) higher than the smallest population P6. Compared to the lowest P1 and P4，Pro content and CAT activity of P8 seeds were the highest with the increase by 517% and 14. 2% (P＜0. 05)，respectively (P＜0. 05)；P1 had the lowest MDA content which was 34. 9% lower (P＜0. 05) than P7. P1 had the highest POD activity and P content which were 3 and 4 times higher than P5 and P4，respectively (P＜0. 05)；P3 had the lowest Ec value，43. 1% lower than P6，and had the highest SOD activity，12. 8% higher than P2(P＜0. 05)；P5 had the highest soluble sugar and starch content，87% and 110% higher than the lowest P6 and P1 respectively (P＜0. 05)；P4 had the highest N content，59. 6% higher than P7(P＜0. 05)；and P9 had the highest K content，27. 2% higher than P4(P＜0. 05).【Conclusion】 The correla‐ tion analyses showed that the germination delay was positively correlated with starch，MDA content and altitude， among which the germination delay was significantly correlated with starch content，thus starch might be an impor‐ tant factor affecting seed germination delay.