Author/Authors :
khattak, baharullah kohat university of science and technology - department microbiology, Kohat, pakistan , saifullah, . university of agriculture - department plant pathology, Peshawar, Pakistan , hussain, shaukat university of agriculture - department of plant pathology, Peshawar, Pakistan , ahmad, musharraf university of agriculture - department plant pathology, Peshawar, Pakistan , ali, asad university of agricultur - department plant pathology, Peshawar, Pakistan , junaid, mohammad university of agriculture - department plant pathology, Peshawar, Pakistan , khan, ijaz ahmad university of agriculture - department of weed science, Peshawar, Pakistan , khan, taj ali kohat university of science and technology - department microbiology, Kohat, Pakistan , hussain, mubbashir kohat university of science and technology - department microbiology, Kohat, pakistan
Abstract :
Trichoderma harzianum is a well-known fungus and is being used as bio control agent for the management of important plant pathogens including root knot nematodes (RKN). In the present studies, 15 isolates of Trichoderma harzianum were collected from different the root knot nematodes-infested tomato field of Malakand and Swat, Pakistan. These isolates were tested for their nematocidal effects against Meloidogyne javanica. Anti-J2 antagonistic test divided the isolates into 5 antagonistic groups or AGs. AG1 was observed as the most antagonistic group, causing an average of 66.6% J2 mortality. Genetic variability among these isolates, was studied at molecular level by randomly amplified polymorphic DNA procedure. A selected set of three random primers was used for this purpose, which resulted in 113 bands on gel for the 15 isolates of T. harzianum. The analysis of the bi-variate data, using Unweighted Paired Groups Method Averages, divided the indigenous isolates of Trichoderma, into four well-defined clusters. These results clearly revealed that there were considerable genetic differences among the Trichoderma isolates. While, there was no correlation, found between RAPD clusters and aggressive groups (AGs). Isolates belonging to different AGs were found scattered among the four RAPD clusters. It was concluded that the indigenous isolates of Trichoderma harzianum were found effective against root knot nematodes and there was a significant difference among these isolates, at the molecular level.
Keywords :
Genetic variability , RAPD , Trichoderma harzianum , Biological control , Meloidogyne , Root knot nematodes
