The Allelopathic Effect Of Phyllostachys Heterocycla Cv. Pubescens Litear And Decomposited Soil To Chinese Fir Seeds In Different Decomposition Stages

Abstract:Along with researching deeply on the mixed forest, people paid attention to construction of mixedforest increasingly. The constructing area of mixed forest increased constantly in southern in country, but asfor how to select excellent mixed species correctly, there was equivalent blindness. The biochemistryrelation( namely allelopathy ) between Phyllostachys heterocycla cv. Pubescens and mixed species wasoften neglected, thus resulted to defeat.Phyllostachys heterocycla cv. pubescens had the important position in farming and forestry economyand industrial structure of forestry. Strengthening its cultivation and ?ndustrialization,can not only quickenthe development of economy, promote the forestry construction of efficiency, but also develop forestryeconomy in mountain area vigorously, help farmers to be rich , accelerate construction of socialism newrural area, improve ecology environment. But many forest farmers planted the pure forest of Phyllostachysheterocycla cv. pubescens in many areas for convenience of construction. It influenced not only theproductivity of forestry land but also its sustainable development..However the former allelopathy research neglected allelopathy of Phyllostachys heterocycla cv.Pubescens litter in the decomposition process. Therefore, the allelopathy of its litter has been mensuratedunceasingly by bioassy in the decomposition process in expectation of the provision of theoreic basis forthe resolution for mixed planting problems.The results of the experiments were following:1 .In the decomposition experiments of litter, Allelochemicals extracted form litter had different effecton the different Chinese fir seeds germination index, sometime Allelochemicals extracted form litter hadinhibitory effects but sometime had stimulating effects.2 Polarity and litter-Polarity allelochemicals extracted from litter had different effect on Chinese firseeds germination index respectively. Among the three concentrations, the inhibitory effect of treatment200mg/kg were prior to that of treatment 100mg/kg and 50mg/kg. In general the low concentration hadstimulating effects and the high concentration hadinh?bitory effects.3．The allelochemicals extracted from litter have the intense inhibitory or stimulating effect on theabsolute germination rate, potential, radicle growth, plumular axis growth, fresh weight and dry weightmarkedly when the decomposition prolong to nine months generally. During the full process ofdecomposition, the amount of allelochemicals were decreased, when the decomposition prolonged totwelve months generally , released allelochemicals had lost activity along with prolonging of thedecomposition. The inhibity or stimulating effects got weak,sometimes,changed into the inhibity orstimulating effects.4 During the decomposition of litter, Allelochemicals extracted form litter sometimes had inhibitoryeffects on Chinese fir seeds germination index at the beginning and weakended or changed into stimulatingeffects later. Allelochemicals extracted form decomposed soil had markly inhibitory or stimulating effectson the absolute germination rate, potential and dry weight , when the decomposition prolonged to ninemonths , but had stimulating effects , after twelve months and sometimes had inhibitory effects on the average of radicle growth, plumular axis growth, fresh weight.Subject words:phyllostachys heterocycla cv. Pubescens;Allelopathic effect; Allelopathy...