桃内果皮木质化与其相关酶的关系

研究了桃果实发育过程中内果皮和中果皮木质素的积累情况与苯丙氨酸解氨酶(PAL)、肉桂醇脱氢酶(CAD)和过氧化物酶(POD)的关系。结果表明:在果实发育前期(花后2~4周),中、内果皮厚度快速增加,内果皮中的PAL和CAD的活性迅速增加,但是在这一时期内果皮的木质素含量增加非常缓慢;在果实发育的中后期(花后5~7周),果实体积增加减慢,PAL,CAD和POD 3种酶活性开始不同程度的降低,但内果皮的木质素却在快速积累。中果皮与内果皮不同,它的PAL,CAD和POD活性一开始就远远低于内果皮,且木质素含量在整个生长阶段一直维持在1.0%以下的低水平。

Relationship between Lignification of Peach Fruit Endocarp and the Activities of Related Enzyme

The relationship between the lignin accumulation and the activities of the phenylalanine ammonialyase,cinnamyl alcohol dehydrogenase and peroxidases in mesocarp and endocarp were studied respectively during the peach fruit development.The results showed that during 2 to 4 weeks after blossom drop the rate of lignin accumulation in the endocarp kept slowly,while the activities of the related enzymes in the same part was increased very quickly,and the thikness of mesocarp and endocarp increased rapidly at the same time.On the other hand,the rate of the fruit growth became slow and the activities of the related enzymes in endocarp were decreased in diffe-rent degree,but the lignin accumulated rapidly in endocarp during 5 to 7 weeks after blossom drop.In the mesocarp,different to in the endocarp,the activities of the phenylalanine ammonialyase,cinnamyl alcohol dehydrogenas and peroxidases were much lower,and the lignin content always kept a low value of 1.0% from the beginning to the end of the period tested.