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.
New record of Aulacophora foveicollis on Clerodendrumindicum (L.) Kuntze from North East India
Aulacophora foveicollis, a polyphagous pest of more than 81 plant species is known for its voracious feeding habit. Studies on occurrence and population density of this pest were carried out under field conditions at Assam Agricultural University, Jorhat. Correlation studies revealed that population density of A. foveicollis showed significant negative correlation with maximum temperature and significant positive correlation with evening relative humidity. Multiple regression equations were developed for A. foveicollis to predict their seasonal incidence under the agro climatic conditions of Jorhat.
Relationship between field and cage assessments for resistance to red pumpkin beetle in summer squash
SummarySignificant differences in resistance to the red pumpkin beetle were observed among summer squash lines in both field and cage experiments. Broad sense heritability estimates were 0.87 and 0.78 for field and cage assessments respectively. Significant positive rank (rs=0.96) and phenotypic (rp=0.76) correlations were observed. Cage evaluation of red pumpkin beetle resistance may be used with confidence in selection programmes of red pumpkin beetle resistance.