TOLERANCE OF TRICHODERMA HARZIANUM RIFAI - A BIOCONTROL AGENT-TO AGROCHEMICALS
Loading...
Date
1992
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
AAU, Anand
Abstract
Biological control strategy has been demonstrated for the management of soil-borne plant diseases where management by other means are difficult. Trichoderma Spp. have gained considerable importance as sole application or integrated with lov/er doses of fungicides. Since,' the biocontrol agent is to be applied in soil, it is important to ascertain its tolerance to various agrochemicals used in the production technology. In the in vitro studies, on the effect of different agrochemicals on the growth and spore germination of Trichoderma harzianum Rifai it was found that the bio-agent could tolerate higher concentrations of chemicals. Among the fungicides like Metalaxyl it could grow well and showed less inhibition in spore germination. Among the different insecticides Aldicarb Phorate and Carbofxiran proved less toxic whereas Phenamiphos proved toxic to T, harzianum. Nematicide Ethoprop was less toxic while Vapam was highly toxic. Of the herbicides tested 2,4-D supported maximum growth and spore germination. All the fertilizers tested except ZnSO. wfirtfnot only supportive but stimulatory to growth and spore germination . Urea was highly stimulatory to growth and spore germination. In generation series and cross-toletance studies T. harzlanxim acquired tolerance/resistance to higher doses of fungicides (Captafol, Captan, Thiram and Carbendazim). In integrated control studies T. harzianum (TH (N))+ fungicide reduced the infection of R. bataticola in cotton and S. rolfsii in peanut significantly. However, a combination of Carbendazim with fungicide-tolerant isolate of T. harzianxim (TH(T)) was most effective in reducing root-rot of cotton while Thiram in combination with TH(T) was the best in reducing stem rot of peanut.
Description
Keywords
Plant Pathology, Agriculture, A STUDY