The Effect Of The Damage Caused By Loudonta Dispar On The Content Of The Secondary Substance And Nutritient Substance Of Phyllostachys Heterocycla Cv. Pubescens

The Effect of the Damage Caused by Loudonta dispar on the Content of the Secondary Substance and Nutritient Substance of Phyllostachys heterocycla cv.pubescensLoudonta dispar (Kiriakoff) is the important pest of the bamboo stands in Fujian Province. In recent years, it has caused grievous disaster to the forests of Phyllostachys heterocycla cv.pubescens in northwest Fujian. The pest mainly harms Phyllostachys heterocycla cv. pubescens,P. viridis,P. glauce,P. iridencens,P.propinqua,P.bambusoides,Pleioblastus amarus and so on. When it greatly happened, it ate up bamboo leaves and brought the bamboo growing poor so much as withering. The pest can do harm to declining the quality of newbo rn bamboo and cutting down the output of bamboo shoot next year.Some knowledge of the pest was studied systematically in the field about biological character and ecological character and technology of forecast. This article studied the effect of the damage caused by Loudonta dispar on the content of the main secondary substances and nutritional substances of Phyllostachys heterocycla cv.pubescens. The study provides scientific basis for screening resistance varieties of bamboo against the pest.The tannin content was determined in blanches and leaves of Phyllostachys heterocycla cv.pubescens before and after the damage caused by Loudonta dispa. The results show that the damage caused by Loudonta dispar has remarkable effect on the tannin content in blanches and leaves of Phyllostachys heterocycla cv.pubescens. The tannin content in blanches and leaves increase after the damage caused by Loudonta dispar. The increasing extent of the tannin content is large in leaves, which increased from 0.402 mg·g-1 to 0.515 mg·g-1. And in blanches, the increasing extent of the tannin content was comparatively narrow, which increased from 0.248 mg·g-1 to 0.282 mg·g-1.The content of phenols was determined in blanches and leaves of Phyllostachys heterocycla cv.pubescens before and after the damage caused by Loudonta dispar. The results show that the damage caused by Loudonta dispar has remarkable effect on the content of phenols in blanches and leaves of Phyllostachys heterocycla cv.pubescens. The content of phenols in blanches and leaves decrease after the damage caused by Loudonta dispar. The content of phenols in leaves decreased form 3.662 mg·g-1 to 3.252 mg·g-1, and the content of phenols in blanches decreased form 1.874 mg·g-1 to 1.671 mg-g-1.The content of flavones was determined in blanches and leaves of Phyllostachys heterocycla cv.pubescens before and after the damage caused by Loudonta dispar. The results show that the damage caused by Loudonta dispar has very remarkable effect on the content of flavones in blanches and leaves of Phyllostachys heterocycla cv.pubescens. The content of flavones in blanches and leaves of Phyllostachys heterocycla cv.pubescens increased remarkably after the damage caused by Loudonta dispar. The flavones content in leaves increased form 3.443 mg·g-1 to 4.630 mg·g-1, and the flavones content in blanches increased form 0.351 mg·g-1 to 0.698 mg·g-1 after the damage caused by Loudonta dispar.The content of soluble sugar and total sugar were determined in blanches and leaves of Phyllostachys heterocycla cv.pubescens in medium damage caused by Loudonta dispar and in no damage. The results show that the content of soluble sugar and total sugar decrease in blanches and leaves of Phyllostachys heterocycla cv.pubescens after the medium damage. In leaves of Phyllostachys heterocycla cv.pubescens, the content of soluble sugar decrease from 112.81 mg·g-1 to 98.34 mg·g-1 after the medium damage caused by Loudonta dispar, and the content of total sugar decrease from 251.7 mg·g-1 to 13.55 mg·g-1. In the blanches of Phyllostachys heterocycla cv.pubescens, the content of soluble sugar decrease from 99.8 mg·g-1 to 86.69 mg·g-1 after the medium damage caused by Loudonta dispar, and the content of total sugar decrease from 218.8 mg·g-1 to 186.38 mg·g-1.The content of protein was determined in blanches and leaves of Phyllostachys heterocycla cv.pubescens in medium damage caused by Loudonta dispar and in no damage. The results show that the content of protein decrease in blanches and leaves of Phyllostachys heterocycla cv.pubescens after the damage caused by Loudonta dispar. The content of protein in leaves of Phyllostachys heterocycla cv.pubescens decrease from 149.45 mg·g-1 to 136.36 mg·g-1 after the medium damage caused by Loudonta dispar, and from 133.11 mg·g-1 to 119.26 mg·g-1 in blanches.The content of potassium (K) was determined in blanches and leaves of Phyllostachys heterocycla cv.pubescens in medium damage caused by Loudonta dispar and in no damage. The results show that the content of K increase remarkably in blanches and leaves of Phyllostachys heterocycla cv.pubescens after the medium or more grievous damage caused by Loudonta dispar. The content of K in leaves of Phyllostachys heterocycla cv.pubescens increase from 8.15 mg·g-1 to 10.13 mg·g-1 after the medium damage caused by Loudonta dispar, and from 7.19 mg·g-1 to 8.40 mg·g-1 in blanches.The content of nitrogen (N) and phosphorus (P) were determined in blanches and leaves of Phyllostachys heterocycla cv.pubescens in medium damage caused by Parasa bicolor (Walker) and in no damage. The results show that the content of N and P decrease remarkably in blanches and leaves of Phyllostachys heterocycla cv.pubescens after the medium damage. In leaves of Phyllostachys heterocycla cv.pubescens, the content of N decrease from 24.84 mg·g-1 to 20.49 mg·g-1 after the medium damage caused by Parasa bicolor, and the content of P decrease from 0.91 mg·g-1 to 0.84 mg·g-1 In the blanches of Phyllostachys heterocycla cv.pubescens, the content of N decrease from 20.12 mg·g-1 to 17.07 mg·g-1 after the medium damage caused by Parasa bicolor, and the content of P decrease from 0.83 mg·g-1 to 0.78 mg·g-1.The interaction between the changes of some chemicals (secondary substance and nutritient substance) in damaged blanches and leaves of Phyllostachys heterocycla cv.pubescens and the population parameters of Loudonta dispar was explored in this paper. The results showed that:slower development, lighter weight, high mortality and higher activity of detoxification enzymes were found in Loudonta dispar population as fed on damaged leaves of Phyllostachys heterocycla cv.pubescens.