Isolation, identification, and pathogenicity of Steinernema carpocapsae and its bacterial symbiont in Cauca-Colombia.

In Colombia, identification of entomopathogenic nematodes (EPN's) native species is of great importance for pest management programs. The aim of this study was to isolate and identify EPNs and their bacterial symbiont in the department of Cauca-Colombia and then evaluate the susceptibility of two Hass avocado (Persea americana) pests to the EPNs isolated. EPNs were isolated from soil samples by the insect baiting technique. Their bacterial symbiont was isolated from hemolymph of infected Galleria mellonella larvae. Both organisms were molecularly identified. Morphological, and biochemical characterization was done for the bacteria. Susceptibility of Epitrix cucumeris and Pandeleteius cinereus adults was evaluated by individually exposing adults to 50 infective juveniles. EPNs were allegedly detected at two sampled sites (natural forest and coffee cultivation) in 5.8% of the samples analyzed. However, only natural forest EPN's could be isolated and multiplied. The isolate was identified as Steinernema carpocapsae BPS and its bacterial symbiont as Xenorhabus nematophila BPS. Adults of both pests were susceptible to S. carpocapsae indicating this EPN potential for its management. The results of this study constitute the first record of S. carpocapsae in Colombia and the susceptibility of P. cinereus to this EPN.

Entomopathogenic nematology in Latin America: A brief history, current research and future prospects.

Since the 1980s, research into entomopathogenic nematodes (EPNs) in Latin America has produced many remarkable discoveries. In fact, 16 out of the 117 recognized species of EPNs have been recovered and described in the subcontinent, with many more endemic species and/or strains remaining to be discovered and identified. In addition, from an applied perspective, numerous technological innovations have been accomplished in relation to their implementation in biocontrol. EPNs have been evaluated against over 170 species of agricultural and urban insects, mites, and plant-parasitic nematodes under laboratory and field conditions. While much success has been recorded, many accomplishments remain obscure, due to their publication in non-English journals, thesis dissertations, conference proceedings, and other non-readily available sources. The present review provides a brief history of EPNs in Latin America, including current findings and future perspectives.

Management of swine mortalities through the use of a mixed composting-accelerating bio-inoculant.

A composting-accelerating bio-inoculant (Bacillus subtilis, Talaromyces sayulitensis (HC1), Steinernema sp., and Heterorhabditis sp.) was evaluated in a composting process made up of a different mix of wood chips, pig manure, urine, and swine mortality (raw material RM). Three different treatments (T1, T2, and T3) were assessed, and physicochemical, microbiological, and entomological evaluations were carried out at 0 and 45 days of the composting process. The highest organic nitrogen (1.34 %) concentration was detected in swine mortality, whereas the highest total oxidizable organic carbon (39.1 %) concentration was observed in wood chips. Salmonella spp., was not identified in any of the raw materials. Clostridium spp., count was 5.5, 2.0, and 1.0 Log10 unit, for pig manure, wood chips, and swine mortality, respectively. Pig manure, swine mortality, and wood chip total coliform count was 6.21, 5.32, and 1 Log10 unit, respectively. Helminth eggs were not detected in any of the RM and Cryptosporidium spp., oocysts were occasionally found in pig manure and wood chips. Several types of flies were identified, Musca domestica, Muscina stabulans, Stomoxys calcitrans, Fannia canicularis, Sarcophaga sp., and Calliphora sp. Treatment 3 (45.11 % swine mortality, 33.33 % wood chips, and 21.55 %, urine and bio-inoculant) had the greatest total oxidizable organic carbon availability, the highest carbon/nitrogen (C/N) ratio (20.67, p < 0.05), and the lowest dipterous larvae count. Moreover, Salmonella sp., was not observed and had only low Clostridium spp., and fecal coliform count. The bio-inoculant's effect on C/N ratio, cation exchange capacity, and electrical conductivity were beneficial, and resulted in production of a fertilizer complying with EPA 600/1-87-014, EPA 40 CFR Part 258, and NTC5167/11 norms. According to the characterization protocols used in this study the compost was apparently free from bacterial and parasitic pathogens and minimal dipteran counts. Last, maturation time was 15 days shorter compared with control (C4).

Biological characterization of the colombian isolate Heterorhabditis sp. SL0708 (Rhabditida: Heterorhabditidae) / Caracterização biológica do isolamento colombiano Heterorhabditis sp. SL0708 (Rhabditida: Heterorhabditidae)

Heterorhabditis sp SL0708 (Rhabditida: Heterorhabditidae) is a native entomopathogenic nematode from Alcalá, Valle del Cauca (Colombia), a natural enemy of insects that can be used for controlling Plutella xylostella L, Conotrachelus psidii Marshall and Delia platura (Meigen); however its biological characterization is unknown. In order to know about the infective capacity of the isolate, tests were made with last instar larvae of Galleria mellonella (Lepidoptera: Pyrallidae) on penetration, one by one, exposure time, dose response and foraging strategy. The average infecting juveniles (IJ) entering larvae was 3 (1.5%). In the one-on-one test, larvae mortality ranged between 8.3 and 16.7%. There was no significant difference (p 0.05) between treatments and in number of dead larvae in the exposure time and dose response assays. Heterorhabditis sp. SL0708 presented a cruiser foraging strategy, which indicates that it can be used for sessile or cryptic hosts.(AU)

Heterorhabditis sp.SL0708, nematoide entomopatogênico nativo de Alcalá, Valle del Cauca (Colômbia), é um inimigo natural que pode ser usado para o controle de Plutella xylostella L, Conotrachelus psidii Marshall e Delia platura (Meigen), porém, a sua caracterização biológica é desconhecida. Assim, ensaios de penetração, um a um, tempo de exposição, exposição a diferentes doses e estratégia de forrageio foram realizados com lagartas de último ínstar de Galleria mellonella (Lepidoptera: Pyrallidae). A média dos juvenis infectantes (IJs) que ingressaram na lagarta foi 3 (1,5%). No ensaio um a um a mortalidade das lagartas oscilou entre 8,3 e 16,7%. Não foram encontradas diferenças significativas entre os tratamentos e o número de lagartas mortas no tempo de exposição e dose. Heterorhabditis sp., apresentou uma estratégia de forrageio de cruzeiro, o que indica que pode ser usado para hospedeiros com hábitos sésseis ou crípticos.(AU)

Virulencia, producción y desplazamiento de nematodos entomopatógenossobre larvas del picudo de la guayaba Conotrachelus psidii Marshall(Coleoptera: Curculionidae) en laboratorio / Virulence, production and dispersal of entomopathogenic nematodes to larvae of the guava weevil Conotrachelus psidii Marshall (Coleoptera: Curculionidae) in the laboratory

El picudo de la guayaba Conotrachelus psidii Marshalles una de las principales plagas del cultivo de la guayaba enSantander - Colombia, causa pérdidas severas afectando lacalidad y cantidad de los frutos. El control biológico es unaopción viable para el manejo de la plaga y en especial, losnematodos entomopatógenos (NEPs) han mostrado buenosresultados (63-90% mortalidad) para el control de larvas decuarto instar del picudo de la guayaba. En el presente estudiose evaluó el efecto de siete especies de NEPs aislados enColombia: Steinernema websteri JCL006, Steinernema sp. 1 JCL024,Steinernema sp. 2 JCL007, Steinernema sp. 3 JCL027, S. colombienseSNI0198, Heterorhabditis bacteriophora HNI0100 y Heterorhabditissp. SL0708 sobre larvas de cuarto instar del picudo de laguayaba en condiciones de laboratorio. También se evaluó laproducción y el desplazamiento de las especies de NEPs másvirulentas. Se registró que Heterorhabditis sp. SL0708 genera unamortalidad del 85% sobre el picudo de la guayaba, Steinernemasp. 1 JCL024 del 75% y S. colombiense SNI0198 del 55%, lasotras especies de NEPs generaron mortalidad menor al 25%.La mayor producción de JI por larva del picudo se registróen Heterorhabditis sp. SL0708, la cual también mostró mayorcapacidad de reconocimiento cuando el hospedero es C. psidii...

Theguava weevil Conotrachelus psidii Marshall is a majorpest affecting guava cultivation in Santander, Colombia;it causes serious losses in the quality and thevolume of fruit produced. Biological control is a viableoption for pest management; entomopathogenicnematodes (EPNs), particularly, have shown goodresults (63-90% mortality) in controlling fourth instarlarvae of the guava weevil. In this study we evaluatedthe effect of seven species of EPNs isolatedin Colombia: Steinernema websteri JCL006, Steinernemasp. 1 JCL024, Steinernema sp. 2 JCL007, Steinernemasp. 3 JCL027, S. colombiense SNI0198, Heterorhabditisbacteriophora HNI0100 and Heterorhabditis sp. SL0708on fourth instar larvae of the guava weevil in laboratoryconditions, and measured the production andthe displacement of the most virulent. Heterorhabditissp. SL0708 induced mortality of 85%, Steinernemasp. 1 JCL024 75% and S. colombiense SNI0198 55%,the other species of EPNs, less than 25% mortality.Increased production of JI by weevil larva wasrecorded in Heterorhabditis sp. SL0708, which alsoshowed greater recognition capability when the hostwas C. psidii...

O bicudo-da-goiaba Conotrachelus psidii Marshall, éuma das principais pragas do cultivo da goiaba no Sanander- Colômbia. Ocasiona perdas muito grandes, afetando aqualidade e a quantidade dos frutos. O controle biológicoé uma opção viável para o manejo da praga, especialmente,os nematóides entomopatogênicos-(NEPs) mostraram bonsresultados (63-90% mortalidade) para o controle do quartoinstar do bicudo-da-goiaba. No presente estudo foi avaliadoo efeito de sete espécies de NEPs isolados na Colômbia:Steinernema websteri JCL006, Steinernema sp. 1 JCL024,Steinernema sp. 2 JCL007, Steinernema sp. 3 JCL027, S. colombienseSNI0198, Heterorhabditis bacteriophora HNI0100 e Heterorhabditissp. SL0708, sobre larvas de quarto instar do picudo da goiabano laboratório. A produção, e o deslocamento das espéciesmais virulentas também foram medidos. Para Heterorhabditissp. SL0708 foi registrada mortalidade de 85%, para Steinernemasp. 1 JCL024 do 75% e para S. colombiense SNI0198 do 55%,as outras espécies de NEPs causaram mortalidade do insetomenor que 25%. A maior produção de JI por larva do bicudofoi registrada em Heterorhabditis sp. SL0708, a qual tambémmostrou maior capacidade de reconhecimento quando ohospedeiro é C. psidii...