Concomitancy of Entomophilous and Soil Transmitted Nematodes in Selected Insects

Abstract

Aim: To determine the occurrence of entomophilous and soil transmitted nematodes of three insect species; Zonocerus variegatus, Gryllotalpa orientalis and Mantis religiosa in Obio Akpor, Local Government Area of Rivers State, Nigeria.
 Methodology: The insect samples were collected with entomological sweep net as described by Colwell [1] and pitfall traps as described by Davies [2]. Insect samples were dissected using Stubbins’ method [3] while nematodes in the insects were isolated and identified according to Cheesborough, (2005).
 Results: Two hundred and forty-eight (248) insect specimens comprising; Z. variegatus 193 (77.8%), G. orientalis 42(16.9%) and Mantis religiosa 13(5.2%) were collected from designated ecological settings based on availability and trapping efficiency. Out of the 248 insects sampled; 145 (58.5%) were infected with three genera of nematodes comprising; Ascaris lumbricoides; 17 (7.5%), Mermis Spp., 148 (65.5%) and Trilabiatus lignicolus 61(27.0%). Mermis Spp., an entomophilous nematode occurred in Z. variegatus and Mantis religiosa due to host specific factors. Nematode occurrence in the host did not indicate sex relationship (P>0.05) however, hosts age influenced parasite occurrence as older insects harbored more parasites (P<0.05). Trilabiatus lignicolus; a free-living soil nematode and A. lumbricoides; a soil transmitted helminthes found in the guts of Z. variegatus and G orientalis was attributed to the feeding habits of the insects. 
 Conclusion: The study indicated that Z. variegatus and G. orientalis as veritable vectors of soil transmitted nematodes while Z. variegatus and Mantis religiose are suitable host of the entomophilous nematode Mermis Spp.

Distribution of Entomopathogenic Nematodes in Some Selected Insect Species in Osogbo Local Government Area of Osun State, Nigeria

“…Previous studies have reported that the abundance of specific insects boosts the rate of EPN infectivity (Demarta et al, 2014;Campos-Herrera, 2015). Ozeum et al (2021) isolated 148…”

“…Following (Ozeum et al ., 2021), the weight (g) of the insect samples was weighed using an electronic measuring scale, while a meter rule was used to measure the standard and total lengths (cm) of the insects. The standard length of the samples involves the length of the insect, excluding the jumping legs, while the total length includes the stretched-out jumping legs of the insects.…”

“…Insect pests’ invasion has become a major setback in achieving sustainable crop production and, thus, leading to food insecurity in Nigeria and other sub-Saharan African countries (Ozeum et al ., 2021). Insect pests cost farmers billions of dollars each year in crop losses and the cost of controlling them (Sharma et al ., 2017).…”

“…The use of chemical insecticides has been the leading measure incorporated to combat an array of insect pests (Isman, 2019). Many are non-biodegradable, contaminate the environment, harm humans and other non-target organisms (Ozeum et al ., 2021). The rising demand for organic food calls for biocontrol alternative to pest control by farmers (Das et al ., 2020).…”