Resistance Mechanism Of Leave Structure To And The Influence Of The Stand And Climatic Factors To Colletotrichum Gloeosporioides

Colletotrichum gloeosporioides Penz. is a main disease of Camellia, often drives large defoliation and fruit drop from Camellia, endangers the output and quality of forest fruit, leads to tree growth recession。In this paper, the epidemic law of Colletotrichum gloeosporioides Penz. such as the relationship between the severity of diseases and the meteorological and stand factors, the relationship between resistance and the epidermal structure of Camellia, the changes law of enzymatic activity before and after the pathogenesis of Camellia leaf, the relationship between resistance of Camellia and the free radical scavenging activity will be researched. The experimental field is the main Camellia -producing areas in Hepeng town Shucheng county。1. Varieties, terrain, canopy density, slope, management level and the stand structure among forest stand factor are found greatly affecting disease occurrence. In different Camellia's varieties, red fruit Camellia's disease is lesser, mottled and green fruit Camellia's disease is heavier. The canopy density is linear negatively related to the disease index and the correlation coefficient is 0.7987. In different terrains, the less serious incidence of Camellia's disease on hilly, the more serious incidence of Camellia's disease on ridgelines. Diseases slope all has great effect. The greater the hill slope, the more serious incidence of disease of Colletotrichum gloeosporioides. There is great correlation between the disease index and the management level. The less serious incidence of disease is due to precise management and the more serious incidence of Camellia's disease is being precise of extensive management of without management.2. In the climatic factors, the study found that the temperature and rainfall have greatly affected the occurrence and epidemic. In a growing season, the incidence of fruit is continuously upward. There are two peak periods. The first is in late May to early June, the second is between Augusts to September in the same year. Young shoot have a peak of disease in late April to early May, and stop in June of the same year.3. Resistance to the leaves epidermal structure of different resistance levels had found that the structure of leaves skin has great influence on resistance. Waxy layer thickness of the leaves, the cuticle thickness, the palisade tissue thickness and cell density of palisade tissue were positive effect on resistance.4. Enzymatic of phenylalanine (PAL), enzymatic of polyphenoloxidase (PPO), enzymatic of peroxidase (POD) of different disease-resistant varieties of Camellia were measured before and after inoculating with Colletotrichum gloeosporioides. The results showed that in the absence of flu cases, three kinds of enzymatic in different disease-resistant were not obvious. After the vaccination, the stronger the disease-resistant varieties have, the faster the increased speed and rate of change rise.5. The relationship between disease-resistant and the clearance rate of leaves, the peel extract against DPPH was also researched. The results showed that in the 2.0 mg / mL concentration, both of leaves or the skin, the clearance rate of DPPH has reached more than 85 percent, the highest more than 90 percent. The free radical scavenging activity is greatly different in leaves and peel extract from different grades disease-resistant, but there is no linear correlation between them. It is linear correlation between the free radical scavenging activity and the concentrations of extractives or between the free radical scavenging activity and the holding time after been added with DPPH.