The Relationship Between Physiological Biochemical Property Of The Populus Tomentosa And The Damage Of Apriona Germari And Its Influence On The Wood Quality

In order to study the influence of Apriona germari on the physiological and biochemical value and wood property of Populus tomentosa, the physiological and biochemical value and wood property of healthy and damaged trees were tested in the study. About the physiological and biochemical value we mainly tested the peroxidase isozymes and esterase isozyme in the leaf, the activity of POD enzyme and PPO enzyme in the leaves and phloem, the content of soluble sugar, total sugar and phenols. And the wood quality tested in the study include physical properties, mechanic and chemical properties, mainly involving the basic density, water content, angential crushing strength, radial crushing strength, Ph value, extraction by hot water and water of 1% NaOH etc. The result showed that:1. The activities of POD enzyme and PPO enzyme in the leaves and phloem of P. tomentosa was tested Using ultraviolet spectrophotometry. The result showed that there was a positive correlation between the damage level and activity of POD enzyme in the leaves and phloem. But the change regular of PPO enzyme was different from that of POD. The activity of PPO arrived max. at moderate damage level, followed by a decreasing at the severe damage in the leaves, While increased all along with the aggravation of damage in the phloem. Variance analysis showed that it arrived 1% significant level between the different damage level and activity of the above enzymes.2. The POD and EST isozyme in the leaves of P. tomentos were studied using incontinous polyaerylamicle electrophoretic(PAGE) method. It showed that the POD and EST isozyme were significantly different in healthy and damaged leaves. The POD isozyme changed remarkably with the increasing of damage. Except.for two basic bands, the others changed clearly including quantity increase, width augment, color dense. The EST isozyme bands also changed with the increasing of damage. But except for the basic two bands, only one band changed mainly in the width augmen and color dense. All these showed that there was a relationship between POD. EST and different damage by A. germari.3. The content of soluble sugar increased with the increasing of damage, but the content of total sugar has not changed regularly. There was positive correlation between the content of phenols and the damage degree by Apriona germari.Variance analysis showed that the discrepancies were significant at 0.01 level. All these showed that the content of sugar and phenols in the P. tomentosa played an important role on A. germariwhen it damaged P. tomentosa.4. The basic density, angential crushing strength and radial crushing strength decreased with the increasing of damage, and all the discrepancies of them were significant at 0.01 level.5. The water content, pH value , extractor by hot water ^ l%NaOH content increased with the increasing of damage, and all the discrepancies of them were significant at 0.01 level.