Inhibition Of Plant Extracts And Residues On Verticillium Dahliae

Verticillium wilt is a kind of soil borne vascular bundle system diseases caused byVerticillium dahliae which affect the production of cotton, cotton fiber length and strength,wide occurrence and harm serious. Verticillium dahliae exists in soil or plants residues in theform of hyphae, spores, and microsclerotium (MS), which is major primary source ofinfection and lie in the soil for many years. Verticillium wilt is the most important fungaldiseases in cotton production. Lacking of plant resources, it is difficult to breeding for diseaseresistance. Chemical prevention and cure exists problems such as high cost, environmentalpollution and biological control influenced by environmental conditions is not stable. As anew environmental protection technology, biological fumigation could effectively control soilborne disease, improve soil structure, increase organic matter and beneficial microbes, whichpromote sustainable agricultural development. Therefore, the experiment selected five plantswith antibacterial action (Chinese chives, welsh onion, mint, ageratum, lavender), studied itsinhibition of plant extracts and residues on mycelium, conidium and microsclerotium,screened plant materials with better biological fumigation ability for new method ofbiological fumigation technology control of Verticillium wilt. The main results were shown asbelow:1. Extracts from5kinds of plant had inhibition effect on mycelium growth andinhibition of methanol-extracted solution was better. With the increase of extractconcentration, the inhibition to mycelium growth was increased. Inhibition of extracts fromChinese chives (Allii tuberosum) was the strongest, followed by mint (Mentha arvensis) andageratum (Agastache rugosa) extracts, lavender (Lavandula spp.) was the weakest.2. Extracts from plants had inhibition effect on spore germination and inhibition ofmethanol-extracted solution was slightly better. With the increase of extract concentration, theinhibition to spore germination was increased. Inhibition of extracts from Chinese chives andwelsh onion was the strongest, followed by ageratum extracts. In addition, lavender and mintshow the trend of low concentration promoted germination and high concentration inhibitedgermination.3. Microsclerotium germination was significantly inhibited by plant residues. Theinhibition of plant residues increased with time prolonged (3weeks to9weeks) and differentplants showed significant differences. Residue of ageratum had the strongest inhibitory effect on microsclerotium germination, followed by mint and Chinese chives. Inhibition of residuefrom lavender was the weakest among the test plants.Overall, Chinese chives, mint or ageratum had significant inhibition to V. dahliae, andpotential and prospects for biological fumigation materials. The results provided the certaintheory basis on prevention and control of Verticillium wilt.