PAPER TITLE :EFFICACY OF PLANT POWDERS OF EUGENIA AROMATICA AND AZADIRACHTA INDICA ON THE RICE MOTH, CORCYRA CEPHALONICA (STAINTON) (LEPIDOPTERA: PYRALIDAE) IN COCOA BEANS IN STORAGE

FUTA JOURNAL OF RESEARCH IN SCIENCE | VOLUME 15 NUMBER 1 2019

Paper Details

  • Author(s) : J. C. Anikwe, 1A. V. Oyedokun
  • Abstract:

The rice moth, Corcyra cephalonica is a notorious insect pest of stored cocoa beans causing quantitative and qualitative economic damage that can lead to total loss of stored beans if not controlled. The use of synthetic fumigants for control of the moth often leaves undesirable residues that could pose health and environmental hazards. Therefore, safer alternative like the use of plant powders could be used. Hence, plant powders of Eugenia aromatica and Azadirachta indica were evaluated for their efficacy as protectants of cocoa beans against the rice moth. Disinfested cocoa beans (50g/jar) were admixed with powders of E. aromatica and A. indica at levels of 0.5 w/w, 1 w/w, 2 w/w and 4 w/w in three replicates with an untreated control under laboratory conditions at ambient temperature of 28 ± 2 oC and relative humidity 72% ± 5%. A cohort of day old adults (n=20) of C. cephalonica were introduced into each container for bioassays. Total adult mortality of the F1 progeny at seven days post-infestation was 100% for both powders at 4 w/w concentration. The LD50 of E. aromatica and A. indica three days after treatment were 1.09 and 11.41 while the LD95 were 2.36 and 149.85, respectively. Percentage bean damage ranged from 10% at 0.5w/w to 0% at 2.0 w/w for E. aromatica  and a similar trend  was recorded for bioassay with A. indica (26% at 0.5 w/w). Both plant powders averted damage of cocoa beans at 2.0 w/w and therefore, can be incorporated into a formidable control strategy of cocoa beans in storage. Keywords: Corcyra cephalonica, Eugenia aromatic, Azadirachta indica, bioassay, cocoa beans