| The result indicate: the main mass media, occurred one generation in Fujian, overwintering as 3-5instar larvae in boring tunnel, still a few low instar larvae in the bark. In the first April, the overwintering larva makes a oval papal chamber in xylem. After 13-15 days, the adult emerges. The adult snaps a circular eclosion hole from the pupal chamber. They often fly out after staying in the eclosion holes for 2-3 days. The amount of adults occur a peak in last May to first June. The female and male is 1 vs. 1. In forest, the adults look for spear extra-nutrition. They like to habitate on Pinus massoniana, P.thunbergii and Cedrus deodara, when forced to feed on the simple plants, the quantity they feeding on Pinus massoniana has outstanding variance with the other plants'. After 5-9 days they mate and lay the eggs in gap they gnawed. On the pine bark there are some teadrop-like pine resin flowing down for oviposition. Usually one egg is laid on a gap, few 2-4 eggs. The eggs last 6-10 days. The larvae feed on the bark inside and phloem after hatched and discharge the mixture composed with white fiber, brown power and feces to the bark. 3-instars bite a elongated oval boring hole to xylem, then the mixture disappear. Only 31.68% of the larvae can bore into xylem for the high mortality. The larvae are easy infested by Beauveria bassiana, the parasitic rate reach up to 40%. The larvae last 260-310 days. The larvae bore around the phloem, quickening the wither of pine. June to October per year is the time that the pine die for Monochamus alternatus Hope infested. By identified, the death of scrub pine in Pingtang are not caused by Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle.Studied on the pine with 6-18 cm DBH, the bigger the DBH, the more amount of the larvae in the trees, the less proportion of the infested tree. Quantity distributions of the larvae in the trunk is lower part (1-4 m)> middle part (5-8 m)>upper part. The amount of larvae in the trunk of less than 2 m are 20.35% of that in the whole trunk, and 94.79% proportion of the infested tree.Measured by clump intensity index, regressive analysis method and zero frequency method, the spatial pattern of Monochamus alternatus Hope is conferred to assemble distribution in pine forest, By zero frequency method, Monochamus alternatus Hope population was "zero frequency dependent". The optimal sampling number of forest survey was analyzed and calculated, and the sequential sampling analysis was presented.Investigating on the emerge hole of Monochamus alternatus Hope on scrub pine (with less than 8 cm DBH, less than 5 m average) in Pingtang, showed that Monochamus alternatus Hope grow well in 1-3 m of the base of the trunk, can develop to adults in the end. The female beetlesdeposit their eggs on weak pine. If the plants have withered since the last year, they oviposit on any longer. The adults bite the gap, sometimes haven't laid the eggs. The gaps which have not eggs are 43.2% of the whole gaps.The infestation experiment on control of Monochamus alternants Hope' high instars with the strains of Steinernema carpocapsae (Weiser,1955) Beijing, Steinernema feltiae (Filipjerm,1934) Otio, Heterorhabditis bacteriophora E-6-7 and Steinernema longicaudum D42 is take in lab. The strains of Beijing Otio are screened to be the best. The most appropriate dose is 10 000 infesting nematodes per longicorn, the control effect can reach over 90%.The conspicuous effect is gained on the control Monochamus alternatus Hope larvae with the strains FA and PH of Beauveria bassiana and Metarhizium anisopliae. They can be applied in the forest. The death of infested is easily contaminated, the spores livability is low, if used in field can't effect well.Soaking the wood block which carry the longicorn larvae with 10% Imidacloprid powder 10 g+water 150 /, 24.5%Quanli missible oil 800X or 4.5% Baichongning messible oil 2 OOOX effect well, the mortality of larvae reach over80% after one hour. But if soaking in water alone, the total mortality reach 81.9% until the...
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