Basic Studies On The Nematode And Ecology From The Rhizosphere Of Pinus Massoniana Lamb

In this paper, based on population and community ecology, we studied mainly on the nematode community in the rhizosphere of Pinusmassoniana Lamb, the community structure , time and space distributional character, the decipline of predominant species, comparing the ecological difference of nematode in the rhizosphere of different geological seedlings of Pinus massoniana Lamb, the species of nematodes, using time sequencing theory in the modeling of one of the nematode population in a year, and ecological factors with the population density of nematode.The results show that, there are 11 genus nematode in the rhizosphere of different geological seedlings of Pinus massoniana Lamb. Those are Aphelenchus , Paratylenchus, Helicotylenchus, Hemicycliphora, Criconemoides, Xiphinema, Longidorus, Trichodorus, Hoplolaimus, Tylenchus, Nothotylenchus.Of all the species , Aphelenchus has the biggest number of population , its absolute density, relative density and prominent value are higher than any other species. The statistic parameters also tell us that, the Jiangxijian geological seedling's nematode community has the biggest diversity and richness, GuizhouDuyun seedling is contra. And GuanxiNingming seedling has the highest evenness index, GuizhouDuyun still contra. Similarity measurements show that AnhuiQiangshan seedling and HubeiYuanAn seedling are most alike. And LaiZhou seedling, Nanping seedling, GuanxiPaiyanshan seedling also are alike.Screened from a local seedling of Nanping, we have got 10 genus and 10 species , that is Tylenchus. exguus* Paratylenchus.minuts, Longidorus. sp, Xiphinema insigne, Macroposthonia, Hemicycliphora, Helicotylenchus. dihystera, Trichodorus obscurus, Aphelenchus avenae, Rhabditidae.Almost in all the samples we screened, Tylenchus. exguus has the predominant population, the second is Rhabditidae and Aphelenchus avenae. The community number of nematode in a year has significant correlation with climate. Population density can be divided into 3 groups: one are developing greatly in spring and autumn, for example, Tylenchus. exguus, Rhabditidae, Aphelenchus avenae; the other are fluctuating slightly in a year, for example Longidorus. sp, others are lower frequnces in seasons, for example Trichodorus obscurus. In summer, both the number and density of nematodes in the rhizosphere of Pinus massoniana Lamb are very low. In the yearly development, although prominent populations of nematodes in the rhizosphere of Pinus massoniana Lamb changed slightly, but prominent value of different populations changed, the diversity index was fluctuating overall.Modeled by time sequencing theory, fiting and forcasting the population number of Tylenchus exiguus , we have got the equation:W.+0. 9952Wt-1=at-1. 0366at-1Statistic and test told that the model is excellent, can be used in the monitor and forcasting .The ecological fato.rs and nematode density' Spearman correlation a organic matter(0. 69), full nitriogen(0. 31), full phosphorus(0. 675), moist hold(0,429) , N/P (-0,333) , N/K(0.119) , P/K(0,467) , PH (-0.173) , s temperature (0,133), Oranglc matter , full phosphorus and full potassium h relatively high correlation , other factors are lower.The vertical distribution of nematode density declines greatly with enlargement of distance from the stem. Several distributional index t that,the horizontal distribution of nematode from the rhizosphere of Pi massoniana Lamb is collective distribution.