Screening of candidate pathogen for the control of coleopterous insect pest in storage
2000
Anon.
The project was primarily conducted to identify potential pathogens for the control of major coleopterous insect pests in storage and to determine the susceptibility of stored grain insects to isolated microorganisms through pathogenicity studies. Survey of pathogens was conducted nationwide, and 36 bacterial strains were collected. These strains of bacteria were tested against the major insect pest in storage namely: Tribolium castaneum, Rhyzopertha dominica, Sitophilus zeamais, S. oryzae and Callosubruchus spp. Two developmental stages of these test insects were used namely, adult and larva. The bacterial isolates were admixed with grain sample either in crude or powdered form at different rates: 250 ul per 20 g, 0.01 per 1 g and 5 to 15 percent per 1 g of diet against adults of test insects. Larvae were treated separately at the dosage of 1 to 5 percent per 1 g of diet. Results revealed that bio-assay using crude preparation at a range of 250 ul per 20 g of diet induced adult mortality to four test insects, but the level of mortality is low. The highest recorded mortality is only 28.8 percent in S. zeamais. On the other hand, bio-assay using 0.01 g per 10 g diet provided the highest corrected mortality of 34.5 percent in R. dominica at 14 days exposure. Increasing the dosage to 5 to 15 percent per gram diet, a mortality of 52.3 percent was recorded in R. dominica. Meanwhile experiment on larval stage of these test insects revealed that using 1 to 5 percent per 1 g of diet gave 31.25 percent corrected mortality in R. dominica. Results of the pathogenicity studies on the bacterial strain tested indicate that among the six test insects used, R. dominica showed the highest susceptibility to bacterial strains tested
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by University of the Philippines at Los Baños