Tropentag, September 17 - 19, 2014 in Prague, Czech Republic "Bridging the gap between increasing knowledge and decreasing resources"

Effect of Endophytic Entomopathogenic Fungi as Biological Control Agents on the Production of Phytohormons in Tomato and Cotton

¹Georg-August-Universität Göttingen, Dept. of Crop Sciences, Division of Agricultural Entomology, Germany
²Georg-August-Universität Göttingen, Dept. of Crop Sciences, Division of Molecular Phytopathology and Mycotoxin Research, Germany

Abstract

This research aimed to establish two strains of the entomopathogenic fungus Metarhizium anisopliae 150 and 153 endophytically in tomato and cotton plants as an innovative biological control strategy against several pests and diseases taking into consideration the possible interaction between these fungi and their hosting plants. Therefore, two inoculation methods were applied using fifteen plants per treatment for a tomato experiment and ten plants per treatment for a cotton experiment; for the seed inoculation method, tomato and cotton seeds were soaked in a mixture of fungal spore suspension with an adjusted concentration to 107 spore/ml and an adhesion material for two minutes. Dry seeds were then planted in 11 cm pots and left to grow for one week under greenhouse conditions. A root inoculation method was conducted by establishing two treatments with clean tomato seedlings at the third leaf growth stage. Roots were washed and dipped in the same mixture for two minutes and re-planted in 11 cm pots. Cotton and tomato leaves were sampled for both inoculation methods. At the same time the same procedure was repeated with tomato plants which were additionally inoculated with Phytophthora infestans, the causal agent of the late blight disease. The plants were grown for two weeks under suitable conditions to develop the disease symptoms. Thereafter, leaves were also sampled. Collected samples were extracted for multiple phytohormons' analyses including salicylic acid, abscisic acid, jasmonic acid, indolic acetic acid and gibberellins using LC-MS. Our results demonstrated that phytohormons levels change in relation to plant species, inoculation method, pathogen presence and fungal bio-agent strain.

Keywords: Biological control, Endophytic entomopathogenic fungi, LC-MS, Metarhizium anisopliae, phytohormons, Phytophthora infestans

Contact Address: Dalia Muftah Alkhayat, Georg-August-Universität Göttingen, Dept. of Crop Sciences, Division of Agricultural Entomology, Göttingen, Germany, e-mail: daliakhayatyahoo.com