INVESTIGATION ON THE MICROFLORA OF THE LONG-TAILED MEALYBUG PSEUDOCOCCUS LONGISPINUS (TARGIONI-TOZZETTI) (HEMIPTERA: PSEUDOCOCCIDAE) IN ORDER TO ASSESS ITS IMPORTANCE AS A CARRIER OF PATHOGENIC MICROORGANISMS

K. G. Trencheva, R. I. Tomov, T. P. Popova

Abstract: Investigations on the microflora of the long-tailed mealybug Pseudococcus longispinus (Targioni-Tozzetti) (Hemiptera: Pseudococcidae) were performed. The following microorganisms were isolated: Salmonella entericа, Serratia plymutica, Enterobacter agglomerans, Staphylococcus cohnii, Bacillus spp., Clostridium spp., Listeria sp., Candida krusei, Penicillium sp., Aspergillus fumigatus. The results from the investigations show that the scale insect could be a reservoir and distributor of conditionally pathogenic for animals and human microorganisms such as bacteria mainly from the family Enterobacteriaceae, staphylococci, spore-forming as well as fungi from the genera Candida and Aspergillus. The presence of fungi of the genus Penicillium is a prerequisite for the development of poliresistance of the identified bacteria to β-lactams which are among the most widely used antibiotics. Such resistance of the microorganisms isolated from P. longispinus was found in vitro by us in this study through the agar-gel diffusion method of Bauer et al. (1966). The coexistence of bacteria and fungi in insects is proving to be a factor which induces development of resistance of bacteria to antibiotics emitted by fungi and probably is one of the reasons for the existence and spread of resistant strains. The carriage of S. plymutica can be assessed as a factor which regulates fungal microflora of the species and probably protects it from entomopathogenic fungi which were not identified in our research.

Keywords: microflora; Pseudococcus longispinus; resistance to antibiotics

Date published: 2017-08-17