Abstract: 【Objective】Explore the influence that the clear cotton Verticillium dahliae harms a root related anti- enzyme in the degree cotton seedling body to the dissimilarity.【Method】Threw away the paper pot and vermiculite etc. when the cotton seedling was long to go to four leaves, use a water to flush carefully, get:⑴ Complete root seedling, ⑵Root the remaining root of the lower part 3-5 cm use to disinfect of the knife slice in order to slice a seedling, ⑶ Stays a main root, cutting off the greatly parts of side root for harm a seedling. Three kinds of different roots cotton seedling that fasten condition immerses to go to by having no germ water dilution a different density in the germ liquid of the 20 ml cotton Verticillium dahliae kleb. Through the 0-48 h with the result that the wilt degree and measures the variety of related anti-enzyme【Result】Slice a seedling victimizes most seriously and secondly in order to harm a seedling, complete root the outbreak that fasten the cotton seedling is the most light.【Conclusion】Result harmed the cotton seedling exterior pathology in root reaction and the dynamic state bio-chemical reaction of the related enzyme inside the body to carry on a research for the cotton, acquired the plant exterior pathology to respond to test with internal bio-chemical to fit together mutually.

Key words: CottonVerticillium dahliae Klebinjure of rootPOD, SOD, MDA