Ecology, Environment and Conservation Paper

ASSESSMENT OF THE NANOSIZED PARTICLES OF ZNO AND MGO AND SOME CULTIVARS IN CONTROL OF ALTERNARIA SOLANI CAUSING TOMATO EARLY BLIGHT

Adnan A. Lahuf, Kadum M. Abdullah and Mushtak T. Mohammadali

Abstract

The aims of this study were to isolate and identify the causal microorganism causing the early blight on tomato and evaluate the efficiency of nano sized particles of ZnO and MgO and three tomato cultivars to control it. Morphological and molecular approaches were employed in diagnosis of the fungal pathogen. Influence of three concentrations (1,3,5 g/L) of two nano particles (ZnO and MgO) were assessed on the pathogen. Subsequently, the three concentrations of ZnO NPs with the three cultivars of tomato were evaluated under field conditions using plastic tunnels in management of the pathogen. The result of the morphological and molecular identification showed that the fungus caused the disease was Alternaria solani. Furthermore, all concentrations of ZnO nano particles proved to be effective against the causative agent achieving an inhibition percentage exceeded 50%. However, same concentrations of MgO NPs did not show efficiency in inhibition of the same pathogen. As well as, all three tomato cultivars were susceptible to pathogen of early blight, although they exhibited various percentages of disease severity with superiority to HLACV that reached the least percentage (21.84%). Additionally, the results demonstrated that the two concentrations (3 and 5g/L) of ZnO NPs were the most effective in causing significant decrease in the percentage of diseased severity to 17.04 and 20.13% respectively comparing with control treatment that was 30.6%. Moreover, a significant integration was attained between the nano sized ZnO particles and the three cultivars in reduction of the disease severity percentage. Consequently, the best combination was between the two concentrations (3 and 5 g/L) and Hlacv. that caused a reduction to 13.20 and 15.72 % respectively compared with 29.51% in control treatment and 30.49% in the fungicide treatment. These results indicate clearly to possibility of replacing the fungicides with the ZnO NPs particularly at concentrations 3 and 5 g/L and the Hla tomato cultivar in the integrated management of early blight caused by A. solani under the circumstances of tunnels and plastic houses in Iraq and this can participate in conserving the environment.