IDENTIFICATION, INSECTICIDAL EFFECT AND ANTIBIOSIS STUDIES OF SOME BACTERIA ISOLATED FROM NATURALLY INFECTED Pectinophora gossypiella (SAUND.) COLLECTED FROM COTTON FIELDS IN EGYPT.

Abstract

One of the important Integrated Pest Management Strategies (IPM) against economic pests in Egypt is the use of biological control methods.The use of entomopathogenic bacteria is one of these methods. The authors achieved four isolates of bacteria from the naturally infected P. gossypiella in cotton fields at Assuit and Kafr El-Sheikh Governorates, Egypt. Isolates were characterized based on morphological properties. Morphological analyses were carried out based on Bergey's Manual of Systematic Bacteriology. The identification of the isolated bacteria was confirmed by using Biolog-System as, Staphyloccus sciuri, Micrococcus luteus, Brevibacterium lines & Brevibacterium casei. In addition, their larvicidal effect was evaluated. The results revealed that, S. sciuri and M. luteus were the most effective against 1 st instar larvae of PBW. Furthermore, their latent effect caused the lowest pupation % resulted from treated PBW larvae. S. sciuri was the most promising bacterial isolate to be developed as a biological control agent against P.gossypiella. The antagonists of bacterial strain against the mycelial growth of the pathogenic fungi (Rhizoctonia solani, Fusarium solani and Macrophomia phaseolina), was experimently tested to evaluate growth reduction of all pathogenic fungi.

The Potential Activities of Two Bacillus thuringiensis Strains Against the Neonate Larvae of Pectinophera gossypiella

“…kurstaki exhibited its effect against S. exigua and Helicoverpa armigera (Zhang et al, 2009), Plutella xylostella (Legwaila et al, 2015). Abou-zeid et al (2015) revealed that Staphyloccus sciuri and Micrococcus luteus were the most effective against 1 st instar larvae of P. gossypiella. Many studies have reported the susceptibilities of lepidopteran larvae to Bt toxins (Alsaedi et al, 2017;Hanen et al, 2016).…”

“…The tested biocide Btk (Dipel 2×) caused different influences on all biological aspects of pink bollworm which decreasing larval duration, pupation percentage and adult emergence (Hegab and zaki 2012). Furthermore, their latent effect caused the lowest pupation % resulted from treated P. gossypiella larvae by Staphyloccus sciuri and Micrococcus luteus (Abou-zeid et al, 2015). The percentages of pupation and adult emergence of P. gossypiella were negatively correlated with the increase of spore-crystal concentration and positively with the increase in the concentration of the supernatant of B. cereus (Mahfouz and Abou El-Ela 2011).…”