Collection and preparation of test materials: S. nodiflora was collected from the Rajshahi University Campus and identified by Prof. A.T.M. Naderuzzaman and a voucher specimen (No. 48, 10-12-1968) was deposited in the herbarium of the Department of Botany, University of Rajshahi. The plants were chopped into small pieces, dried under shade and powdered using a hand grinder, weighed and placed in separate conical flasks to add Pet. E., CHCl3 and MeOH (Merck, Germany) (100gm × 300ml × 2times) for 48h. Filtration was done by Whatman filter paper (made in USA) at 24h interval in the same flask followed by evaporation until the extract were left. The extracts was then removed to glass vials and preserved in a refrigerator at 4?C with proper labeling. Collection and culture of test insect: Adults of T. castaneum were reared in glass beakers (500ml) in a standard mixture of whole-wheat flour (ref) with powdered dry yeast (19:1) in an incubator at 30 ±0.5°C without light and humidity control for continuous supply of adults during experimentation. Dose-mortality test: The dose-mortality responses of S. nodiflora were observed by surface film method. The concentrations used were 3.57, 3.05, 2.54, 2.04 and 1.52mg cm-2 for Pet. E., 3.57, 3.05, 2.54, 2.04, 1.52 and 1.02mg cm-2 for CHCl3, and 2.54, 2.04, 1.52, 1.02, 0.52 and 0.25mg cm-2 for MeOH extract. Each of the doses were diluted in 1ml of solvent, poured into Petri dishes and allowed to dry. Ten adult beetles were released in each Petri dish, and the experiment of all the doses for each of the extracts were replicated three times. The mortality of the beetles was assessed after 12, 24, 36, 48 and 60h of exposures. Repellent activity: The repellency test was adopted from the method (No. 3) of McDonald et al. (1970) with some modifications. Half filter paper discs (Whatman No. 40, diameter 9 cm) were treated with the selected doses of 0.079, 0.039, 0.020, 0.010 and 0.005mg cm-2 for Pet. E. extract and were then attached lengthwise, edge-to-edge, to a control half-disc with adhesive tape and placed in the Petri dishes. The orientation was changed in the two remaining replicates to avoid the effects of any external directional stimulus affecting the distribution of the test insects. Ten adult insects were released in the middle of each of the filter paper circles. The similar process was done for the CHCl3 and MeOH extracts respectively. Each concentration of each solvent was tested for five times. Insects that settled on each of the non-treated half of the filter paper discs were counted after 1h and then observed repeatedly at hourly intervals for five hours. The average of the counts was converted to percent repellency (PR) using the formula of Talukder and Howse (1993, 1995): PR = (Nc – 5) × 20, where, Nc is the percentage of insects on the untreated half of the disc. Brine shrimp nauplii lethality test: Brine shrimp eggs were purchased from Kalabagan, Dhaka and kept in aerated seawater at room (25-30°C) temperature and took 30-48h to give nauplii. The series of concentration were 499.3, 249.6, 124.8, 62.5 and 31.2ppm for Pet. E., 499.5, 249.7, 124.8, 62.5 and 31.5ppm for CHCl3 and 600, 300, 150, 75 and 37.5ppm for MeOH extract. Ten freshly hatched nauplii were added to each of the test tubes with different concentrations mentioned earlier and observed mortality after 6, 12, 18, 24 and 30h of exposures. The data was then subjected to probit analysis.