ISOLATION OF SOME PATHOGENETIC MICROORGANISMS IN PLANTS AND TESTING THE RESISTANCE ACTIVITY OF SOME BIOLOGICAL PRODUCTS

Abstract

Tea tree (Camellia sinensis), Bac Son tangerine (Citrus reticulata Blanco) and black sticky canarium (Canariumtramdenum) are the plants bringing the high economic value to farmers. However, Vietnam has a tropical climate, it is often damp. This is the favourable condition for growth of pathogenic microorganisms in plants. This paper presents the research results about isolation of some pathogenic microorganisms in tea, tangerine and black sticky canarium trees and testing the resistance activity of some biological products. There are 05 strains of bacteria and 02 strains of fungi causing disease in tea, tangerine  and black sticky canarium isolated. The extract from different parts of Picria felterrae Lour by ethanol for 72 hours has ability to inhibit Q2 bacterial strains in tangerines (concentration of 200 g/l) and N1 fungi strain in tea (concentration of 150 g/l). The complex Er(Asp)₃phenCl₃.3H₂O (concentration of 10 μg/ml) is capable of inhibiting 5 bacterial strains isolated including: C1 strain in tea, T1 and T2 strains in black sticky canarium, Q1 and Q2 strains in tangerine.