HOST SUITABILITY OF RED PUMPKIN BEETLE, AULACOPHORA FOVEICOLLIS (LUCAS) AMONG DIFFERENT CUCURBITACEOUS HOSTS
The red pumpkin beetle, Aulacophora foveicollis (Lucas) is a common, serious and major pest of a wide range of cucurbitaceous vegetables. It is injurious to the crops and cause severe damage to almost all cucurbits. The present study was conducted to find out the host suitability of red pumpkin beetle, Aulacophora foveicollis (Lucas) among different cucurbit hosts in the Laboratory and Field Laboratory of the Department of Entomology, Bangladesh Agricultural University, Mymensingh. This study was investigated with a view to explore a resistant host to this pest. The experiment was laid out in the completely randomized design (CRD) and Randomized Complete Block Design (RCBD) in laboratory and field respectively with five replications. Three cucurbit hosts such as sweet gourd (Var. BARI Sweet gourd1), bitter gourd (Var. Hybrid Nepali) and bottle gourd (Var. Kajla) were selected to conduct this research work. Host suitability was determined depending on the average number of beetles present per plant in field. But in the laboratory host suitability was measured following force feeding and choice feeding bioassays. In the field at three different stages of the plant the highest number of beetle per plant was observed on the sweet gourd and the lowest number was found on bitter gourd. Similarly both in force feeding and choice feeding bioassays the highest leaf feeding was observed on sweet gourd and the lowest leaf feeding was determined on the bitter gourd. Both in the laboratory and field among the three cucurbit hosts sweet gourd was the most suitable and bitter gourd was the least suitable host for red pumpkin beetle.
HOST RANGE AND FOOD PREFERENCE OF THE RED PUMPKIN BEETLE, AULACOPHORA EOVE/COLLIS LUCAS (CHRYSOMELIDAE: COLEOPTERA)
Studied on the host range and food preference of red pumpkin beelle, A. foveicollis Lucas revealed that 10 cucurbitaceous vegetables were its host range except bitter gourd. Of major 11 cucurbitaceous crops, musk melon (Cucumis melo L.) was the most preferred food. It causes more damage to the crops of Zaid season than kharif.
Instrumentation and Automated Photometric Titration Procedure for Total Acidity Determination in Red Wine Employing a Multicommuted Flow System
An automated procedure for photometric titration of red wine and associated instrumentation is described. The procedure was based on the flow-batch approach implemented employing multicommutation. The photometric detection was carried out using a homemade LED-based photometer. The mixing device, LED, and photodetector were attached to the titration chamber in order to form a compact and small-sized unit. The flow system comprised an automatic injector and three-way solenoid valves, which were controlled by a microcomputer through an electronic interface card. The software, written in Quick BASIC 4.5, was designed with abilities to accomplish all steps of the titration procedure including data acquisition and real-time processing to decide about the course of titration in the following step and so forth, until the titration endpoint was reached. The usefulness of the proposed titration system was demonstrated by analyzing red wine samples. When results were compared with those obtained using the AOAC reference method, no significant difference was observed at the 95% confidence level. A relative standard deviation of ca  2% (n=9 ) was obtained when processing a typical red wine sample containing 7.3 gl -1 total acidity expressed as tartaric acid.