| The pest's green control is the key way to improve fruit quality,based on field investigation and experiment,studies are carried out on the occurrence pattern of Oligonychus ununguis(Jacobi)(mite for short) and Dichocrocis punctiferalis Guenee(borer for short) which are the main pests in Yanshan Area,and the resistance of main chestnut cultivars to pests,the green control method to pests,the effect of production measure on the harm of pests,it established the foundation for the green control on main pests of chestnut.The main results are as follows:In April 27 to May 1(leaf-expansion period),the overwintering eggs starts to hatch,it enters the peak period in May 7～12(shoot growth period),it start the most earliest in the sunny slope,the latest in the shade slope.From May 5(leaf-expansion period) the population density of mite raises gradually, around July 15(embryonic development period)it comes to the peak,around August 15-25(fruit expanding period) it vanishes in the field.The occurrence quantity of sunny slope is the highest,the foothill belt is the lowest.The cultivars of Zundali and Zipo have high resistance to mite.The leaves'up-epidermis thickness,hair length and density of down-epidermis have significant correlation with mite-resistance;the phenols and flavonoids content,the activity of SOD,POD,PPO,PAL have close relationship with the mite-resistance.The 1.8%Avermectin EC4000～5000 times liquid or 10% Avermectin-Pyridaben EC2000～2500 times liquid have high control effect and high efficiency-cost ratio to mite.The 1st,2nd,3rd key control periods to mite are May 25,June 15,July 1 respectively. Growing grass in chestnut orchard can decrease the harm of mite.The planting space such as 3m×3m, 3m×4m,3m×5m,4m×4m can decrease the harm of mite.In May 10～15(leaf-expansion period),the adult borer appears in Zunhua,the overwintering generation appears mainly in the 3rd ten days of May to 2nd and 3rd ten days of June(male inflores- cene period to male flower full bloom period),the peak appears in June 10～15(initial and full bloom period of male flower);the first generation mainly appears in 3rd ten days of June to 3rd ten days of July(full bloom period of female flower to embryonic development period),the peak appears in July 10～15(embryonic development period);the second generation mainly appears in 1st ten days to 3rd ten days of August(expanding period of shell and fruit),the peak appears in August 5～15(first expanding period of shell);the third generation mainly appears in 1st ten days to 3rd ten days of September (expanding period of fruit and nut mature period),the peak appears in September 6～17(expanding period of fruit and nut mature period).The occurrence quantity of mountain area is higher than flatland.The cultivars of Zundali and Tafeng have high resistance to borer.The rate of clustered shell,shell volume have significant correlation with borer-resistance,the phenols,flavonoids content of shell and peel have close relationship with borer-resistance.Using the pest-killing lamp and sex pheromone to lure and kill adult borer are the best control method to borer.Picking up the fruit for harvest and clear up shells in orchard can decrease harm of borer.The height of shell accumulation lower than 70cm,the period of shell accumulation in 4～6d,the rate of bored fruit can be decreased.
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