Biocontrol potential of indigenous entomopathogenic nematodes from Cameroon against scale insect pest Stictococcus vayssierei and tending ant Anoplolepis tenella

2020 ◽  
Vol 149 ◽  
pp. 104321
Author(s):  
Françoise Ngo Kanga ◽  
Stefan Hauser ◽  
Maurice Moens
2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Cynthia Ann Dichusa ◽  
Rolando Ramos ◽  
Sitaram Aryal ◽  
Neil Pep Dave Sumaya ◽  
Nanette Hope Sumaya

Abstract Background The tobacco cutworm, Spodoptera litura [Fab.] (Lepidoptera: Noctuidae), is a devastating insect pest of several crops. Entomopathogenic nematodes (EPNs) of the families Heterorhabditidae and Steinernematidae are used as an alternative control measure in lieu of the hazardous synthetic chemical applications. Results A survey of naturally occurring EPNs was conducted across the province of Cotabato, Philippines, covering a total of 5 municipalities with 25 villages. Galleria-baiting technique was employed to recover nematodes from peanut and grassland soils. Out of 50 soil samples collected, only 5 samples harbored nematodes, indicating a recovery of 10%. Preliminary morphological data identified only one EPN under the genera Heterorhabditis (1 isolate), whereas 4 were facultative necromenic nematodes from the genera Metarhabditis (2 isolates) and Oscheius (2 isolates). Analysis of D2D3 segments of the 28S rDNA confirmed high sequence similarity to Heterorhabditis indica, Metarhabditis rainai, Oscheius insectivora, and Oscheius sp. This is the first record of H. indica and M. rainai in the entire region, whereas the first record for Oscheius spp. in the Philippines. Furthermore, the biocontrol potential of the local H. indica infective juvenile (IJ) populations (PIGCD1) isolated from peanut was assessed against the tobacco cutworm, S. litura, under laboratory conditions. The mean percentage mortality caused by H. indica on S. litura at 7 different concentrations ranged from 0-100% at 24 h post inoculation. The lethal concentration (LC50) required to kill 50% of the S. litura larvae population with H. indica was 7.13±1 (IJs/larva). Conclusions The use of Galleria-baiting method is a convenient approach to detect EPNs including other facultative necromenic nematodes from the soils. Obtained data indicated that the local H. indica isolate can be a promising alternative measure to suppress the economically important insect pest, S. litura, and this may provide significant outlook to establish the biocontrol program in the country.


2021 ◽  
Vol 95 ◽  
Author(s):  
R. Pervez ◽  
U. Rao

Abstract The legume pod-borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae) (LPB), is an important insect pest of pigeon pea. Chemical pesticides are generally employed to manage this pest, but because of the soil residue issues and other environmental hazards associated with their use, biopesticides are also in demand. Another benign alternative is to use entomopathogenic nematodes (EPNs) to manage this vital pest. In the present study, the infectivity of ten native EPNs was evaluated against LPB by assessing their penetration and production in the LPB. The effectiveness of the promising EPNs against second-, third- and fourth-instar LPB larvae was also studied. Heterorhabditis sp. (Indian Agricultural Research Institute-Entomopathogenic Nematodes Rashid Pervez (IARI-EPN RP) 06) and Oscheius sp. (IARI-EPN RP 08) were found to be most pathogenic to LPB, resulting in about 100% mortality within 72 h, followed by Steinernema sp. (IARI-EPN RP 03 and 09). Oscheius sp. (IARI-EPN RP 04) was found to be the least pathogenic to LPB larva with 67% mortality. Maximum penetration was exhibited by Heterorhabditis sp. (IARI-EPN RP 06) followed by Oscheius sp. (IARI-EPN RP 08), whereas the lowest rate of penetration was exhibited by Oscheius sp. (IARI-EPN RP 01). The highest rate of production was observed with Oscheius sp. (IARI-EPN RP 08), followed by Oscheius sp. (IARI-EPN RP 04 and 10). Among the tested instars of the LPB larvae, second-instar larvae were more susceptible to EPNs, followed by third- and fourth-instar larvae. The results indicate that Heterorhabditis sp. (IARI-EPN RP 06) and Oscheius sp. (IARI-EPN RP 08) have a good potential to the manage LPB.


Zootaxa ◽  
2010 ◽  
Vol 2527 (1) ◽  
pp. 1 ◽  
Author(s):  
DOUGLAS J. WILLIAMS ◽  
DANIÈLE MATILE-FERRERO ◽  
DOUGLASS R. MILLER

The adult female of the scale insect Stictococcus vayssierei Richard is described and illustrated. The species feeds on the root system of cassava (Manihot esculenta) (Euphorbiaceae) in Equatorial Africa, affecting tuber formation of the plant. Although damage has been reported only recently, the species has probably remained unnoticed because of its subterranean habit. The distribution and host plants of this species are listed and the segmentation of the adult female of Stictococcus is discussed to help describe the characters in detail when specimens are prepared on microscope slides. Six other species of Stictococcus are described or discussed: S. formicarius Newstead, S. intermedius Newstead, S. pujoli Richard, S. sjostedti Cockerell & Cockerell, S. subterreus Williams, Matile-Ferrero & Miller sp. n., and S. formicarius var. tuberculata Laing which is here raised to specific rank as S. tuberculatus Laing.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
José M. Herrera ◽  
Bruno Silva ◽  
Gerardo Jiménez-Navarro ◽  
Silvia Barreiro ◽  
Nereida Melguizo-Ruiz ◽  
...  

AbstractPest control services provided by naturally occurring species (the so-called biocontrol services) are widely recognized to provide key incentives for biodiversity conservation. This is particularly relevant for vertebrate-mediated biocontrol services as many vertebrate species are of conservation concern, with most of their decline associated to landscape modification for agricultural purposes. Yet, we still lack rigorous approaches evaluating landscape-level correlates of biocontrol potential by vertebrates over broad spatial extents to better inform land-use and management decisions. We performed a spatially-explicit interaction-based assessment of potential biocontrol services in Portugal, using 1853 pairwise trophic interactions between 78 flying vertebrate species (birds and bats) and 53 insect pests associated to two widespread and economically valuable crops in the Euro-Mediterranean region, olive groves (Olea europaea subsp. europaea) and vineyards (Vitis vinifera subsp. vinifera). The study area was framed using 1004 square cells, each 10 × 10 km in size. Potential biocontrol services were determined at all those 10 × 10 km grid-cells in which each crop was present as the proportion of the realized out of all potential pairwise interactions between vertebrates and pests. Landscape correlates of biocontrol potential were also explored. Our work suggests that both birds and bats can effectively provide biocontrol services in olive groves and vineyards as they prey many insect pest species associated to both crops. Moreover, it demonstrates that these potential services are impacted by landscape-scale features and that this impact is consistent when evaluated over broad spatial extents. Thus, biocontrol potential by vertebrates significantly increases with increasing amount of natural area, while decreases with increasing area devoted to target crops, particularly olive groves. Overall, our study highlights the suitability of our interaction-based approach to perform spatially-explicit assessments of potential biocontrol services by vertebrates at local spatial scales and suggest its utility for integrating biodiversity and ecosystem services in conservation planning over broad spatial extents.


1999 ◽  
Vol 82 (1) ◽  
pp. 14 ◽  
Author(s):  
Forrest W. Howard ◽  
Avas Hamon ◽  
Michael Mclaughlin ◽  
Thomas Weissling ◽  
Si-lin Yang
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document