Efficacy Of Eucalyptus Plant Extracts Against Lesser Grain Borer

ABSTRACT: The efficacy of insecticidal activities of eucalyptus plant extracts was evaluated against lesser grain borer. Four doses viz. 0.5, 1.0, 1.5 and 2.0% along with control were applied. All tested extracts showed significant efficiency against lesser grain borer with respect to adult mortality, residual and repellency test but stem extracts was the most effective. Adult’s mortality was increased proportionally with the increased time intervals and the toxicity was dose dependent. The stem extracts showed the highest toxic effect (mortality 40.3%) whereas leaf extract showed the lowest toxic effect (mortality, 17.4%). In case of residual study, the highest number of adult emergence was recorded in control (100.0) whereas the lowest (45.5) was in stem extracts. Similarly, the highest infestation inhibition (69.9%) was found in stem extract. Among three plant parts of eucalyotus, stem extract showed the highest repellent effect (74.6%), whereas leaf extract showed the lowest effect (59.3%). On the basis of LD50 values, the stem extract also showed the highest toxic effects. The results suggested the ability of plant extracts for store grains protection as a safe alternative to insecticides. 

Keywords: Lesser grain borer, repellent, mortality, plant extract