Mortality and progeny production of four stored-product insect species on three grain commodities treated with Beauveria bassiana and diatomaceous earths

Author(s):  
Waqas Wakil ◽  
Thomas Schmitt ◽  
Nickolas G. Kavallieratos
2018 ◽  
Vol 54 (No. 2) ◽  
pp. 111-117 ◽  
Author(s):  
Bugti Ghulam Ali ◽  
Bin Wang ◽  
Na Cao ◽  
Feng Lin Hua

An experimental trial was conducted to determine the pathogenicity of Beauveria bassiana strain 202 (Bb-202) against multiple targeted sucking insect species that are serious pests of crops and ornamental plants. The insect species, Myzus persicae Sulzer (Hemiptera: Aphididae), Jacobiasca formosana Paoli (Hemiptera: Cicadellidae), Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae), and Stephanitis nashi (Hemiptera: Tingidae) were exposed to conidia of B. bassiana at rates of 1.0 × 10<sup>2</sup>, 3.5 × 10<sup>3</sup>, 5 × 10<sup>4</sup>, and 6.75 × 10<sup>5 </sup>conidia/mm<sup>2</sup> to determine the pathogenicity of B. bassiana. The fungal strain Bb-202 showed the highest pathogenicity to M. persicae and 100% corrected mortality observed in the treatments over 1.0 × 10<sup>2 </sup>conidia/mm<sup>2</sup>, followed by the J. formosana with the final corrected mortality of 86.6, 94.4, and 97.4% after 10 days of fungal inoculation with 3.5 × 10<sup>3</sup>, 5 × 10<sup>4</sup>, and 6.75 × 10<sup>5 </sup>conidia/mm<sup>2</sup>, respectively. The strain Bb-202 also showed good pathogenicity to B. tabaci and corrected mortalities of 77.9 and 81.1% were recorded when exposed to 5 × 10<sup>4</sup> and 6.75 × 10<sup>5 </sup>conidia/mm<sup>2</sup>. Relatively weak pathogenicity was observed in S. nashi, in which the highest corrected mortality of 63.7% occurred at 6.75 × 10<sup>5 </sup>conidia/mm<sup>2</sup>. Accordingly, the LC<sub>50 </sub>and LT<sub>50 </sub>values of concentrations 1 × 10<sup>5</sup>, 1 × 10<sup>6</sup>, 1 × 10<sup>7</sup>, and 1 × 10<sup>8</sup> conidia/ml were calculated for M. persicae, J. formosana, B. tabaci, and S. nashi that were determined as 6.7 × 10<sup>4</sup>, 1.3 × 10<sup>6</sup>, 3.6 × 10<sup>6</sup>, and 1.2 × 10<sup>7</sup> conidia/ml and LT<sub>50</sub> was observed as 5.2~8.24, 5.1~6.6, 7.2~9.0, and 7.9~9.6 in days, respectively.


2020 ◽  
Author(s):  
Ying Yin ◽  
Bo Chen ◽  
Shuangxiu Song ◽  
Bing Li ◽  
Xiuqing Yang ◽  
...  

ABSTRACTFungal chemodiversity is well known in part due to the production of diverse analogous compounds by a single biosynthetic gene cluster (BGCs). Usually, similar metabolites are produced by closely related fungal species. Here we report a rare case of the production of the cyclodepsipeptide beauveriolides (BVDs) in three insect pathogenic fungi. We found that the more closely-related fungi Beauveria bassiana and B. brongniartii produce structurally distinct analogs of BVDs whereas the rather divergently evolved species B. brongniartii and Cordyceps militaris produce structural analogs in a similar pattern. It was verified that a conserved BGC containing four genes is responsible for BVD biosynthesis in three fungi including a polyketide synthase (PKS) for the production of 3-hydroxy fatty acids (FAs) with chain length variations. In contrast to BVD production patterns, phylogenetic analysis of the BGC enzymes or enzyme domains largely resulted in the congruence relationship with fungal speciation. Feeding assays demonstrated that a FA with a chain length of eight carbon atoms was preferentially utilized whereas a FA with a chain longer than 10 carbon atoms could not be used as a substrate for BVD biosynthesis. We also found that addition of D-type amino acids could not enable B. bassiana to produce those analogs biosynthesized by other two fungi. Insect survival assays suggested that the contribution of BVD to fungal virulence might be associated with the susceptibility of insect species. The results of this study enrich the knowledge of fungal secondary metabolic diversity.IMPORTANCEFungal chemotaxonomy is an approach to classify fungi based on fungal production of natural compounds especially the secondary metabolites. We found an atypical example that could question chemical classification of fungi in this study: the more closely-related entomopathogenic species Beauveria bassiana and B. brongniartii produce structurally different analogs of the cyclodepsipeptide beauveriolides whereas the rather divergent species B. brongniartii and Cordyceps militaris biosynthesize similar analogs under the same growth condition. The conserved BGC containing four genes is present in each species and responsible for beauveriolide production. In contrast to the compound formation profiles, the phylogenies of biosynthetic enzymes or enzymatic domains show associations with fungal speciation relationship. Dependent on insect species, production of beauveriolides may contribute to fungal virulence against insect. The findings in this study augment the diversity of fungal secondary metabolisms.


Author(s):  
Nguyen Van Hieu ◽  
Nguyen Van Vinh

An intensive field survey on aquatic insects of Me Linh Station for Biodiversity in Vinhphuc province was conducted in December 2015. Specimens were collected at 8 different sites and aquatic insects were collected both quantitatively by Surber net and qualitatively by hand net, pond net. As a result, a total of 110 aquatic insect species belonging to 98 genera, 49 families and 9 orders were recognized. Among these, the order Ephemeroptera had the highest species number with 26 species, followed by Odonata with 25 species, Trichoptera with 18 species, Coleoptera with 15 species, Hemiptera with 11 species, Diptera with 9 species. Lepidoptera, Plecoptera and Megaloptera had the lowest of species number, represented by 3 species of Lepidoptera, 2 species of Plecoptera and 1 species of Megaloptera. Besides, the quantitative analysis results and the functional feeding groups were provided.


2017 ◽  
Vol 43 (1) ◽  
pp. 27 ◽  
Author(s):  
Fabiola Villegas-Rodríguez ◽  
Ovidio Díaz-Gómez ◽  
J. Sergio Casas-Flores ◽  
Clara Teresa Monreal-Vargas ◽  
Fernando Tamayo-Mejía ◽  
...  

El psílido de la papa Bactericera cockerelli afecta a las solanáceas en México, por el daño directo que causa, además, de que es transmisor de patógenos procariotes como Candidatus Liberibacter solanacerum (psyllaurous). Este insecto es combatido principalmente con productos químicos. Sin embargo, en la actualidad, se buscan nuevas estrategias para su manejo como el uso de hongos entomopatógenos. El objetivo de este trabajo fue evaluar la susceptibilidad del psílido de la papa a dos cepas comerciales y dos nativas de Metarizhium anisopliae y Beauveria bassiana, así como confirmar la identificación de las mismas mediante técnicas moleculares. Los bioensayos se realizaron con la cepa nativa MA25 de M. anisopliae y las comerciales Metabich® (MA28) y Bassianil® (BB09) y la nativa BB42 de Be. bassiana. Se probaron cinco concentraciones sobre ninfas del tercer estadio de B. cockerelli y se obtuvieron sus CL50 y CL95. Todas las cepas resultaron patógenas para el psílido de la papa, las más tóxicas fueron BB09, BB42 y MA28. La mortalidad fluctuó entre 90 a 100% con las concentraciones más altas de cada cepa: la más virulenta fue BB09, con una CL50 de 2,99 x 104 conidias mL-1 y MA25 la menos virulenta tuvo una CL50 de 6,34 x 105 conidias ml-1. Mediante la clonación y la secuenciación de la región ITS de los rADN 18S, se corroboró que las cepas nativas identificadas por morfología microscópica y claves taxonómicas corresponden a Be. bassiana y M. anisopliae.


Author(s):  
Santhosh Pillai ◽  
AYODEJI EMMANUEL AMOBONYE ◽  
Prashant Bhagwat

2009 ◽  
Vol 5 (9) ◽  
pp. 25-38
Author(s):  
Martha Giselle Rivera Pineda ◽  
Sandra Patricia Garzón Lozano ◽  
Luz Inés Villarreal Salazar

En busca de una alternativa de control del mosquito Culex quinquefasciatus en áreas urbanas se desarrolló el proyecto: “Evaluación de microorganismos biocontroladores sobre el mosquito Culex quinquefasciatus” cuyo objetivo fue evaluar la capacidad biocontroladora de diferentes hongos entomopatógenos sobre larvas del mosquito a nivel de laboratorio. Se evaluaron 16 aislamientos de hongos en diferentes concentraciones. Se constataron diferencias en el porcentaje de mortalidad producido en larvas de Cx. quinquefasciatus dependientes del tipo de aislamiento, de la concentración utilizada y del tiempo de exposición. Los aislamientos que presentaron el nivel de mortalidad más alto pertenecen a la especie Metarhizium anisopliae, seguidos por aislamientos de la especie Beauveria bassiana. El aislamiento que presentó el mayor nivel de mortalidad (100%) en menor tiempo de exposición (24 horas) fue Metarhizium anisopliae 99068 en una concentración de 1x106 e/ml. Por lo tanto este aislamiento es recomendado para su evaluación en campo y desarrollo de un producto comercial.


2005 ◽  
Vol 58 ◽  
pp. 140-147 ◽  
Author(s):  
M.R. McNeill ◽  
C.J. Fletcher

Nodding thistle receptacle weevil Rhinocyllus conicus and gallfly Urophora solstitialis attack the capitula of nodding thistle Carduus nutans L Between 31 October and 15 December 2003 the phenology of both R conicus and U solstitialis was studied at a dryland site in Canterbury Adult R conicus were more numerous than U solstitialis on capitula throughout the experiment Larvae of R conicus were first found on 11 November (15 of capitula infested) and peaked on 2 December with 53 of capitula infested Only 3 of capitula were infested by U solstitialis Adult R conicus or U solstitialis emerged from 79 of the selected primary and secondary capitula The majority of infested capitula (81) contained only R conicus 2 contained only U solstitialis while 17 contained both insect species Parasitism of R conicus by the braconid parasitoid Microctonus aethiopoides was low and occurred when most weevil eggs had been laid


2020 ◽  
Vol 105 (3) ◽  
pp. 281-299
Author(s):  
Javier Carreño-Barrera ◽  
Luis Alberto Núñez-Avellaneda ◽  
Maria José Sanín ◽  
Artur Campos D. Maia

Solitary, dioecious, and mostly endemic to Andean cloud forests, wax palms (Ceroxylon Bonpl. ex DC. spp.) are currently under worrisome conservation status. The establishment of management plans for their dwindling populations rely on detailed biological data, including their reproductive ecology. As in the case of numerous other Neotropical palm taxa, small beetles are assumed to be selective pollinators of wax palms, but their identity and relevance in successful fruit yield were unknown. During three consecutive reproductive seasons we collected data on population phenology and reproductive and floral biology of three syntopic species of wax palms native to the Colombian Andes. We also determined the composition of the associated flower-visiting entomofauna, quantifying the extent of the role of individual species as effective pollinators through standardized value indexes that take into consideration abundance, constancy, and pollen transport efficiency. The studied populations of C. parvifrons (Engel) H. Wendl., C. ventricosum Burret, and C. vogelianum (Engel) H. Wendl. exhibit seasonal reproductive cycles with marked temporal patterns of flower and fruit production. The composition of the associated flower-visiting entomofauna, comprised by ca. 50 morphotypes, was constant across flowering seasons and differed only marginally among species. Nonetheless, a fraction of the insect species associated with pistillate inflorescences actually carried pollen, and calculated pollinator importance indexes demonstrated that one insect species alone, Mystrops rotundula Sharp, accounted for 94%–99% of the effective pollination services for all three species of wax palms. The sequential asynchronous flowering of C. parvifrons, C. ventricosum, and C. vogelianum provides an abundant and constant supply of pollen, pivotal for the maintenance of large populations of their shared pollinators, a cooperative strategy proven effective by high fruit yield rates (up to 79%). Reproductive success might be compromised for all species by the population decline of one of them, as it would tamper with the temporal orchestration of pollen offer.


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