The allelopathy research of the endophytic fungi?￠????s secondary metabolite in pleioblastus amarus(keng)keng f.

摘要

This paper reveals the allelopathy on the following three crops, brassica campestris L, Raphanus sativus L and Lactuca sativa through studying the seed germination and the seedling growth of the five different elution parts (marked part a, b, c, d, e) produced by the secondary metabolites of the Xylaria sp.(LI). Makes the first endophytic -fungi separation for the (Pleioblastus amarus (Keng) Keng f.) grown on the campus of Zhejiang University of Agriculture and Forestry; obtained the fungi assayed to be Xylaria sp.(L1) by adopting the methods of morphological observation and molecular biology;separate and obtained its secondary metabolites after making a liquid fermentation for separated Xylaria sp.(L1); Use the methods of culture dish and cuvette to study the influence of different parts of the secondary metabolites in Xylaria sp.(L1) on the seed germination and seedling growth of the following three crops (Brassica campestris L.), (Raphanus sativus L), and (Lactuca sativa). Different extract parts of Xylaria sp.(L1) and its secondary metabolites have double concentration effects, that is, “Low concentration promotion but high concentration inhibition” on the germination rate and germination index of the two crops (Raphanus sativus L), and (Lactuca sativa), with no influence on that of (Brassica campestris L.); High density Xylaria sp. (LI) and its secondary metabolites have a clear inhibiting effects on the root-length, seedling height and the raw weight of the three crops (Brassica campestris L.), (Raphanus sativus L), (Lactuca sativa), while the a,b,c parts of the low-density Xylaria sp. (LI) and its secondary metabolites have a clear facilitating effect on the root-length, seedling height and the raw weight of (Lactuca sativa); the c part of the low-density culture solution also has a clear facilitating effect on the root-length, seedling height and the raw weight of (Brassica campestris L.). In a certain concentration, the Xylaria sp. (LI) and its secondary metabolites both have clear inhibiting effects on the seed germination and seedling growth of the three crops, and the higher the concentration of the culture solution, the stronger the inhibiting effect.