Study On Biological Characteristics And Chemical Control Of Henosepilachna Vigintioctomaculata(Mots.)

This paper aims at researching the biological characteristic, population fluctuation trend, overwintering status of the Mots through laboratory experiment and field survey as well as investigating the influence of different host to the Mots.'s growth and the relationship between the different host and the Mots.'s physiology and biochemistry. This paper also makes a preliminary research of Henosepilachna vigintioctomaculata Control to Mots. The main results are as below:1. The Mots of East area in Hei Longjiang Province can breed one generation usually, some individuals can breed two generations and there are some areas with multi-generations phenomenon. Overwintering as adult Mots., and the overwintering is usually around the early of June, the adult Mots start to wake and mate frequently. The best spawning period is the last third of June and the best hatching time of the nympha is the first 10 days of July. The best pupation time is at the end of July, the pupal stage is 4 to 6 days averagely. The best eclosion time of the adult Mots is around the middle third of August.2. The Mots. grows up to adult Mots after the overwintering. The SCP and FP will be lowered gradually along with the bitter winter's coming. The SCP and FP will be increased gradually along with climate warming. There are some correlations between the phreatic water amount in the overwintering and grown Mots and its SCP. This paper is to approach the diapause internal mechanism of the adult Mots through the testing of the amount change of the bio-chemicals in the adult Mots. The SCP of the grown Mots is increasing along with the raising of phreatic water amount. The grease is being decreased during the overwintering and the amount of protein is changing like a"V". Long time sun exposure is good to the spawning and high temperature is good for the growth of the Mots'diapause. The spawning quantity is different if the Mots that is out of overwintering, but the grown Mots'lifetime is relatively longer. The lifetime of the Mots removing the diapause is shorter, but it has a large amount of spawning eggs and long spawning time.3. The growth period of the Mots nympha is different from each other due to their different fedding host plant. The Mots nympha fedding on eggplant and pepper is smaller, slow growth, and difficult to complete its growth compared with the Mots nympha fedding on potato. The survival rate of the Mots fedding on potato can reach to 58.33% and it also reach to 51.61% if fedding on Nightshades. However, the growth period is shorter if fedding on potato and the weight of the nympha and pupae is relatively high with large amount of spawned egg and long spawning time, but the complete puberty of its grown Mots is the shortest.4. The selection of the Mots to the different potato are variety: the spawning chooses the Atlantic>Kexin 13> Kexin 12>NL 02-2; the selection of the hatching nympha to the different variety Kexin 13> the Atlantic > NL 02-2> Kexin 12; the grown Mots. prefers Kexin 13 and Kexin 12 more. The physical properties and chemical property of 4 different kinds of potatoes are tested by this paper and the result shows: Blade Thickness Kexin 13> Kexin 12> the Atlantic > NL 02-2, but the Palisade Tissue Thickness, the Atlantic > NL 02-2. The relevance analysis indicated that there is obviously positive correlation between the grown Mots and Sponge tissue thickness. The research also found that there are some relevance with the blade mao quantity on the different variety when the Mots.choose the Host. Also, there is negative correlation between the spawning on the blade and the blade mao quantity. Further more, the selection of the grown Mots. to the different potato hosts is in connection with the amount of Soluble Protein and Free amino acids on the blade with positive correlation. There is no any relevance with the amount of sucrose, soluble sugar and diastase.5. Through the laboratory experiment and field survey of the effect of some kinds of biocides on the Mots, the experiment result indicates: The relative cytotoxic capacity of 6 kinds of chemical agent is sorted as followed: 2.5% Cyfluthrin>1% Azadirachtin>0.2% Regent>3% Acetamiprid >90% Trichlofon>90% Monosultap. There are 4 kinds of biocides with high virulence used for field Sparge, of which the effect of 2.5% Cyfluthrin is the best for good control and long period of validity. 7 days after medicament application, the Pharmacological effects of each medicament will be decreased, but the control rate can still keep above 80%. The Pharmacological effects of 2.5% Cyfluthrin and 90% Monosultap is still more than 90%.