Isolation and Identification of Endophytic Bacteria from Okra Plant and Evaluation of Its Efficiency Against Spiny Bollworm Erias insulana (Boisd)

Abstract

Abstract Twenty-eight endophytic bacteria were isolated from Okra plant grown in several regions in Salah El-Din-governorate fields including Balad, Ishaqi, Tikrit and Baiji. Bacterial cell treatment of isolate SB1 gave the highest rates of mortality on the third instar larvae of the spiny bollworm E. insulana reached to 66.66%, followed by isolate SB 3, which reached to 53.33%, while the isolates ST2, ST5, ST6, SB4, SJ2, SJ3, SJ5, SS2, SS3, as well as the control did not achieve any mortality rate. The results of the treatment of bacterial filtrates in the third instar larvae of the spiny bollworm showed the highest mortality rate was 93.33% by the isolate SB1, followed by 80.00% by the isolate SB3, while the filtrates of bacterial isolates SS5, SS1, SJ7, SJ3, SB5, ST4, and ST3 did not achieve any mortality rate. The results of the molecular diagnosis according to the nucleotide sequence analysis of the 16S rRNA gene and the conformity with the strains recorded in the World Genetic Bank (NCBI) showed the highest bacterial isolates in killing the insect, which included the isolates SB1, SB3, SB6, SJ6, and ST7 return to the species Brevibacillus laterosporus, Bacillus amyloliquefaciens, Bacillus thuringiensis, Bacillus subtilis and Lysinibacillus sphaericus and recorded in the World Genetic Bank under the accession numbers ON844995.1, ON844985.1, ON844996.1, ON844994.1. ON845438.1, respectively.