English

Abstract

The current research work was conducted for the evaluation of repellent and growth inhibitory potential of Azadirachta indica, Murraya koenigii, Nicotiana tobacum and Liquorice against Callosobruchus chinensis (L.). Each plant extract was tested with four concentrations viz; 5, 10, 15 & 20 % for bioassay experiments. Repellent potentials of acetone extract of the plants were evaluated by using the area preference method against the pulse beetle. The four dilutions of the extracted plant materials (extract) were used at one half of the filter papers (of each) while remaining halves were solely treated with acetone (used as control experimental unit) for the comparison purposes. Data regarding repellence were taken after 12, 24 and 48 hours of the post treatment. In repellency bioassay, the highest (93.32%) repellence of Callosobruchus chinensis was observed for which against 20% concentration of A. indica extract, whereas lowest repellence (78.87%) was recorded in case of Liquorice. Repellency values of 90.07% and 84.76% were recorded in extracts of M. koenigii and N. tobacum in Faisalabad strain. In case of Lahore strain highest repellence of C. chinensis was observed for which 95.16% at 20% concentration of A. indica extract was whereas relatively lowest value (82.04%) was recorded in case of Liquorice. Repellency values of 87.27% and 91.06% were recorded in extracts of M. koenigii and N. tobacum. The results regarding growth inhibitory effect revealed that highest mean progeny inhibition (78.12%) was noted at 20% dose rate of A. indica extracted plant material after longest exposure time (60 days). Comparatively lowest inhibition (28.21%) was noted after 30 days exposure period at 5% dilution of Liquorice extract in Faisalabad strain. Mean inhibition of progeny was found directly dependent on both time as well as concentration, applied. Results revealed that highest mean progeny inhibition (85.03%) was recorded at 20% concentration of A. indica extract after longest exposure time (60 days). Comparatively, lowest inhibition (35.18%) was recorded at 5% after 30 days of application of Nicotiana tobacum extract in Lahore strain. Hence, use of plant-based materials can be helpful for the ecofriendly management of the stored grains insect pests as a part of IPM program.