MOLECULAR BARCODING AND PHYLOGENY ANALYSIS OF GONIOZUS NEPHANTIDIS (HYMENOPTERA: BETHYLIDAE), A LARVAL PARASITOID OF COCONUT BLACK HEADED CATERPILLAR, OPISINA ARENOSELLA (LEPIDOPTERA: OECOPHORIDAE)

Abstract Background Biological nitrogen fixation is catalyzed by Mo-, V- and Fe-nitrogenases that are encoded by nif, vnf and anf genes, respectively. NifB is the key protein in synthesis of the cofactors of all nitrogenases. Most diazotrophic Paenibacillus strains have only one nifB gene located in a compact nif gene cluster (nifBHDKENX(orf1)hesAnifV). But some Paenibacillus strains have multiple nifB genes and their functions are not known. Results A total of 138 nifB genes are found in the 116 diazotrophic Paenibacillus strains. Phylogeny analysis shows that these nifB genes fall into 4 classes: nifBI class including the genes (named as nifB1 genes) that are the first gene within the compact nif gene cluster, nifBII class including the genes (named as nifB2 genes) that are adjacent to anf or vnf genes, nifBIII class whose members are designated as nifB3 genes and nifBIV class whose members are named as nifB4 genes are scattered on genomes. Functional analysis by complementation of the ∆nifB mutant of P. polymyxa which has only one nifB gene has shown that both nifB1 and nifB2 are active in synthesis of Mo-nitrogenase, while nifB3 and nifB4 genes are not. Deletion analysis also has revealed that nifB1 of Paenibacillus sabinae T27 is involved in synthesis of Mo-nitrogenase, while nifB3 and nifB4 genes are not. Complementation of the P. polymyxa ∆nifBHDK mutant with the four reconstituted operons: nifB1anfHDGK, nifB2anfHDGK, nifB1vnfHDGK and nifB2vnfHDGK, has shown both that nifB1 and nifB2 were able to support synthesis of Fe- or V-nitrogenases. Transcriptional results obtained in the original Paenibacillus strains are consistent with the complementation results. Conclusions The multiple nifB genes of the diazotrophic Paenibacillus strains are divided into 4 classes. The nifB1 located in a compact nif gene cluster (nifBHDKENX(orf1)hesAnifV) and the nifB2 genes being adjacent to nif or anf or vnf genes are active in synthesis of Mo-, Fe and V-nitrogenases, but nifB3 and nifB4 are not. The reconstituted anf system comprising 8 genes (nifBanfHDGK and nifXhesAnifV) and vnf system comprising 10 genes (nifBvnfHDGKEN and nifXhesAnifV) support synthesis of Fe-nitrogenase and V-nitrogenase in Paenibacillus background, respectively.

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Novel Virulent Bacteriophages Infecting Mediterranean Isolates of the Plant Pest Xylella fastidiosa and Xanthomonas albilineans

Viruses ◽

10.3390/v13050725 ◽

2021 ◽

Vol 13 (5) ◽

pp. 725

Author(s):

Fernando Clavijo-Coppens ◽

Nicolas Ginet ◽

Sophie Cesbron ◽

Martial Briand ◽

Marie-Agnès Jacques ◽

...

Keyword(s):

Phage Therapy ◽

Xylella Fastidiosa ◽

Infected Plant ◽

Mediterranean Area ◽

Genomic Features ◽

Phylogeny Analysis ◽

Plant Pest ◽

European Regulations ◽

Surrogate Host

Xylella fastidiosa (Xf) is a plant pathogen causing significant losses in agriculture worldwide. Originating from America, this bacterium caused recent epidemics in southern Europe and is thus considered an emerging pathogen. As the European regulations do not authorize antibiotic treatment in plants, alternative treatments are urgently needed to control the spread of the pathogen and eventually to cure infected crops. One such alternative is the use of phage therapy, developed more than 100 years ago to cure human dysentery and nowadays adapted to agriculture. The first step towards phage therapy is the isolation of the appropriate bacteriophages. With this goal, we searched for phages able to infect Xf strains that are endemic in the Mediterranean area. However, as Xf is truly a fastidious organism, we chose the phylogenetically closest and relatively fast-growing organism X. albineans as a surrogate host for the isolation step. Our results showed the isolation from various sources and preliminary characterization of several phages active on different Xf strains, namely, from the fastidiosa (Xff), multiplex (Xfm), and pauca (Xfp) subspecies, as well as on X. albilineans. We sequenced their genomes, described their genomic features, and provided a phylogeny analysis that allowed us to propose new taxonomic elements. Among the 14 genomes sequenced, we could identify two new phage species, belonging to two new genera of the Caudoviricetes order, namely, Usmevirus (Podoviridae family) and Subavirus (Siphoviridae family). Interestingly, no specific phages could be isolated from infected plant samples, whereas one was isolated from vector insects captured in a contaminated area, and several from surface and sewage waters from the Marseille area.

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A new species of Glyptapanteles (Hymenoptera: Braconidae: Microgastrinae), a larval parasitoid of Elymnias hypermnestra (Linnaeus) (Lepidoptera: Nymphalidae), along with some new host records of parasitoids from Peninsular India

Zootaxa ◽

10.11646/zootaxa.3227.1.3 ◽

2012 ◽

Vol 3227 (1) ◽

pp. 54 ◽

Cited By ~ 4

Author(s):

ANKITA GUPTA ◽

BLAISE PEREIRA

Keyword(s):

New Species ◽

New Host ◽

Peninsular India ◽

Larval Parasitoid ◽

Hymenopteran Parasitoids ◽

First Time ◽

A New Species ◽

New Host Records

A new species, Glyptapanteles hypermnestrae Gupta and Pereira, is described from Maharashtra, India, and comparedwith closely allied species. This new species was bred from parasitized larvae of Elymnias hypermnestra (Linnaeus) (Lep-idoptera: Nymphalidae). In addition to this, two hymenopteran parasitoids, Apanteles folia Nixon (Braconidae: Microgas-trinae) and Brachymeria indica (Krausse) (Chalcididae), are for first time reported parasitizing larvae of Arhopalaamantes (Hewitson) (Lepidoptera: Lycaenidae) and pupae of Pareronia valeria (Cramer) (Lepidoptera: Pieridae) respectively.

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Beneficial arthropod behavior mediated by airborne semiochemicals. VIII. Learning of host-related odors induced by a brief contact experience with host by-products inCotesia marginiventris (Cresson), a generalist larval parasitoid

Journal of Insect Behavior ◽

10.1007/bf01053293 ◽

1989 ◽

Vol 2 (2) ◽

pp. 217-225 ◽

Cited By ~ 82

Author(s):

Ted C. J. Turlings ◽

James H. Tumlinson ◽

W. Joe Lewis ◽

Louise E. M. Vet

Keyword(s):

Larval Parasitoid ◽

By Products ◽

Beneficial Arthropod

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Incidence of Helicoverpa armigera (Lepidoptera: Noctuidae) and its natural enemies on smallholder crops in Kenya

Bulletin of Entomological Research ◽

10.1017/s0007485300029205 ◽

1993 ◽

Vol 83 (3) ◽

pp. 321-328 ◽

Cited By ~ 10

Author(s):

H. van den Berg ◽

M. J. W. Cock ◽

G. I. Oduor ◽

E. K. Onsongo

Keyword(s):

Helicoverpa Armigera ◽

Heliothis Armigera ◽

Population Densities ◽

Parasitoid Species ◽

Larval Parasitoid ◽

Total Percentage ◽

Four Seasons ◽

Helicoverpa Armígera ◽

Lepidoptera Noctuidae ◽

Experimental Plots

AbstractSmallholder crops (sunflower, maize, sorghum and cotton) were grown in experimental plots at seven sites, representing different agricultural zones of Kenya, over four seasons. Helicoverpa armigera (Hübner) (formerly Heliothis armigera) only occasionally achieved population densities sufficient to cause obvious damage to the crops, and was virtually absent from the coastal sites. At the inland sites, infestation and mortality levels varied greatly. Information is presented on the incidence of H. armigera, and the identity, distribution and frequency of its common parasitoids and (potential) predators, sampled in the experimental plots. Trichogrammatoidea spp., egg parasitoids, and Linnaemya longirostris (Macquart), a tachinid late-larval parasitoid, were the most common parasitoid species, but total percentage parasitism was rather low. Of the large complex of predators, only anthocorids and ants (predominantly Pheidole spp., Myrmicaria spp. and Camponotus spp.) were sufficiently common and widespread to be of importance in suppressing H. armigera. The abundance of predators fluctuated widely between sites, but anthocorids were most abundant at the western sites.

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