激素浸种对薄壳山核桃种子萌发的影响及其种子吸胀过程中SOD和POD活性变化

Effect of phytohormone soaking on seed germination of Carya illinoinensis and change in SOD and POD activities during its seed imbibition process

薄壳山核桃﹝Carya illinoinensis （ Wangenh.） K. Koch﹞为胡桃科（ Juglandaceae）山核桃属（ Carya Nutt.）植物，又名美国山核桃、长山核桃，是世界上著名的经济树种之一[1-2]。目前，主要采用本砧嫁接的方法培育薄壳山核桃良种嫁接苗，而培育优质实生苗作为砧木是该技术的关键环节之一，因此，了解其种子萌发特性极为重要。目前，对薄壳山核桃种子萌发特性的研究主要集中在植物激素催芽方面[3-5]，而有关激素催芽过程中的适宜浸泡天数、种子吸胀过程中相关的酶活性变化等问题尚不明确。

By using L9 （ 3^3 ） orthogonal experimental design, effects of type, mass concentration and soaking time of phytohormones on seed germination of Carya illinoinensis （ Wangenh.） K. Koch were studied, and changes in SOD and POD activities were analyzed during its seed imbibition process. The result of orthogonal experiment shows that compared with the control, soaking seed with different mass concentrations of IAA, GA3 and 6-BA at different times can improve germination rate and decrease rot rate of seeds. In which, phytohormone mass concentration has the greatest influence on germination rate, while seed soaking time has no significant effect on it. According to the experimental results, it is preliminarily determined that suitable soaking condition for seed germination of C. illinoinensis is soaking seeds for 3 d with 200 mg·L-1 GA3 . In addition, SOD and POD activities increase obviously during seed imbibition process, in which, SOD activity appears the trend of first increasing and then decreasing, while POD activity increases continuously.