Article History

Red pumpkin beetle (Aulacophora africana Weise) is an important defoliator and vector of pathogens to its numerous crop hosts. Control had largely been by synthetic insecticides with their attendant consequences on man and the environment thus necessitating scientific studies on environmental-friendly management strategies. The experiment was conducted in the Research Farm of Federal University Wukari in the month of May 2019 with the aim of evaluating the attractiveness of A. africana to Light-emitting diode (LED) and Incandescent Light bulb colours. Five colours (red, yellow, green, blue and white) were used for the study. Each colour light was properly projected on 2 metre vertical screen (made of white polyethene) placed one meter above the ground. A setup without bulb served as the control. The light traps were arranged in a completely randomized design (CRD) in 6 replicates and ran simultaneously for six hours (1800 to 2400hrs). The pumpkin beetles attracted were collected in tubs containing soapy water. A. africana collected were counted and recorded according to bulb type and colour. Samples were identified at the Insect Museum of Ahmadu Bello University, Zaria. Among the Incandescent bulbs, White colour was most attractive to A. africana (4.30±0.38) while red attracted the least (0.71±0.01). Among LED bulbs, Blue was most attractive (3.99±1.01) while Red also attracted the least (0.78±0.03). Overall, LED attracted more pumpkin beetles than Incandescent bulb even though Student Newman Keul’s test indicates that the difference between them was due to random variation (p = 0.16). Correlation and regression analyses indicated increase in insect attraction with increased light intensity. The results, therefore, suggest that white Incandescent or blue LED bulb colours can be incorporated into insecticidal light traps to suppress their population/attract them away from host plants or fixed into ordinary light traps to harvest the insect for scientific studies.

Article History Keywords Attractiveness Hexapod orders Incandescent Light colours Light-emitting diode (LED) Light trap Phototactic.Dearth of information on response of hexapod orders to light sources and colours informed this study. The study was conducted in Federal University Wukari, Nigeria in the month of May, 2019 to evaluate the attractiveness of hexapod orders to Lightemitting Diode (LED) and Incandescent bulb light colours. Daily sampling using fabricated light traps with 5 different colours (white, yellow, red, green and blued) for each bulb type in 6 replicates was done. A trap with no lighting source was the control. Hexapods collected were sorted into their respective orders. Of the overall 13 insect orders collected, LED bulbs attracted 11 while incandescent, 10. Even though, certain hexapod orders exhibited higher affinity to specific colours, statistical analysis revealed that of the 11 orders from LED, differences in the mean number of insects attracted among the bulb colours was significant (p<0.05) only in Coleoptera and Lepidoptera while for incandescent bulb colours, the mean number of insects attracted was significant for Coleoptera, Lepidoptera, Hemiptera, Hymenoptera, Orthoptera, Mantodea, Odonata and Homoptera. Insect orders generally had higher affinity to white and blue colours. LED bulb colours significantly attracted higher number of insects than their corresponding incandescent colours, except for white on which incandescent was more attractive (p>0.05). Overall, attractiveness to hexapod orders increases with rinsing light intensity and LED bulbs were found to be more attractive to hexapods than do incandescent bulbs. Therefore, LED bulbs of higher light intensity with colours around the blue/white spectrum show potential for use in manipulating hexapods for man's benefit. Contribution/Originality:This study discovers that hexapod orders are largely highly responsive positively to blue and white electric light of higher intensity. It also shows that, the LED bulbs were generally more attractive to the hexapod orders than the incandescent. This knowledge can be harnessed in manipulating the hexapods for man's benefit.