Abstract The zoanthid Palythoa caribaeorum secretes a large quantity of mucus that acts as a substrate for microbial communities. Culturable bacteria associated with P. caribaeorum mucus in northeastern Brazil were evaluated through 16S rRNA gene sequences. Proteobacteria was the dominant group, followed by Actinobacteria and Firmicutes. Vibrio was the most common genus, although other groups with the ability to produce biosurfactants and compounds with antimicrobial activity were also present. The studies of culturable marine bacteria may contribute to the understanding of the associated microbial community, opening new opportunities to explore biotechnological potential of microbiota.

O objetivo deste trabalho foi avaliar a suscetibilidade das lagartas Anticarsia gemmatalis (Lepidoptera: Erebidae) e Chrysodeixis includens (Lepidoptera: Noctuidae) às proteínas Cry1 e Vip3A, bem como determinar se há a interação entre essas proteínas no controle das duas espécies. Bioensaios com as proteínas isoladas e em combinações foram realizados, e as concentrações letais CL50 e CL90 foram estimadas para cada condição. As proteínas Cry1Aa, Cry1Ac e Vip3Af foram as mais efetivas no controle de A. gemmatalis, enquanto Cry1Ac, Vip3Aa e Vip3Af foram mais efetivas no de C. includens. As proteínas Cry1Ac e Cry1Ca causaram maior inibição do desenvolvimento das larvas sobreviventes à CL50, em ambas as espécies. Combinações entre Vip3A e Cry1 apresentam efeito sinérgico no controle das espécies e a combinação Vip3Aa+Cry1Ea destaca-se no controle de A. gemmatalis e C. includens. Essas proteínas combinadas são promissoras na construção de plantas piramidadas, para o controle simultâneo das pragas.

The objective of this work was to evaluate the susceptibility of Anticarsia gemmatalis (Lepidoptera: Erebidae) and Chrysodeixis includens (Lepidoptera: Noctuidae) caterpillars to Cry1 and Vip3A proteins, as well as to determine if there is any interaction between these proteins on the control of the two species. Bioassays with both isolated and combined proteins were carried out, and lethal concentrations LC50 and LC90 were estimated for each condition. Cry1Aa, Cry1Ac, and Vip3Af were the more effective proteins for the control of A. gemmatalis, while Cry1Ac, Vip3Aa, and Vip3Af were more effective for the control of C. includens. Cry1Ac and Cry1Ca proteins caused the highest inhibition to the development of larvae that survived the LC50 dose in both species. Different combinations of Vip3A and Cry1 have synergistic effect in the control of both species, and the combination Vip3Aa + Cry1Ea showed an outstanding control of A. gemmatalis and C. includens. These proteins are promising for building pyramided plants for the simultaneous control of the pests.

A bactéria Bacillus thuringiensis Berliner produz um corpo de inclusão paraesporal (cristal) de natureza proteica, formado durante a esporulação, que atua de forma eficiente no controle de insetos-praga de culturas economicamente importantes. Esse cristal é constituído de proteínas Cry, que são codificadas pelos genes cry; um isolado pode ser caracterizado pelo conteúdo de genes cry que apresenta. Visando caracterizar novos isolados no combate de insetos-praga pertencentes às ordens Lepidoptera e Coleoptera, 76 isolados bacterianos foram analisados molecularmente e tiveram seu potencial de controle avaliado por meio de bioensaios com larvas de Spodoptera frugiperda (J.E. Smith), Sphenophorus levis Vaurie e Tenebrio molitor Linnaeus. As análises moleculares indicaram 11 isolados (14,5% da coleção), contendo genes lepidóptero-específicos e 17 (22,37%) com genes coleóptero-específicos. As análises de patogenicidade revelaram dois isolados com alto potencial de controle para lagartas de S. frugiperda, um para larvas de S. levis e seis prejudiciais ao desenvolvimento das larvas de T. molitor. Esses isolados de B. thuringiensis podem ser promissores no controle biológico das referidas pragas.

Bacillus thuringiensis Berliner produces protein crystals that act effectively on the control of pests for several relevant crops. The cry genes codes for these proteins are named Cry proteins. The cry gene profile can potentially set each bacterial isolate as a potential pest control agent. Aiming to analyze new isolates for the controlling of pests belonging to the orders Lepidoptera and Coleoptera, 76 samples were molecularly analyzed and had their potential for control evaluated through bioassays with larvae of Spodoptera frugiperda (J.E. Smith), Sphenophorus levis Vaurie and Tenebrio molitor Linnaeus. Based on molecular analysis data, 11 samples (14.5%) were able to control lepidopteran specific pests due to their cry genes content, and 17 samples (22.37%) exhibited coleopteran specific cry genes. The bioassays results indicated two samples with highly effective against S. frugiperda, one against S. levis and six with high toxicity against T. molitor larvae development. The selected B. thuringiensis isolates may be promising for the biological control of these pests.

A bactéria entomopatogênica Bacillus thuringiensis (Bt) é um agente de controle com características tóxicas e ambientais que permitem o controle de insetos-praga de acordo com as premissas do Manejo integrado de pragas (MIP). Com o objetivo de buscar novas linhagens potencialmente tóxicas para Sitophilus oryzae L. 1763 (Coleoptera: Curculinidae), caracterizaram-se molecularmente 1,073 isolados de B. thuringiensis de regiões do Brasil. O material genético foi extraído através do kit InstaGene Matrix, utilizado para a amplificação das seqüências através da técnica de Polymerase chain reaction PCR, sendo os resultados visualizados em gel de agarose 1,5%. A classe do gene cry35Ba foi representada por 60 isolados (5,6%) de Bt, os quais foram submetidos a bioensaio com larvas de S. oryzae. Quatro causaram mortalidade acima de 50% nos testes de patogenicidade e os isolados 544 e 622 foram os mais virulentos, conforme determinado pela estimativa da CL50. Nos quatro isolados que demonstraram toxicidade, foram detectados cristais esféricos, bipiramidais e cubóides, além de proteínas com 44 kDa, referentes aos genes cry35Ba por Sodium dodecil sulphate - polyacrilamide gel electrophoresis (SDS-PAGE). Estes dados demonstram o potencial de Bt no manejo de S. oryzae.

The entomopathogenic bacterium Bacillus thuringiensis is a control agent with toxic and environmental characteristics that allows the control of pest insects according to the Integrate Pest Management (IPM) precepts. In order to find new strains, potentially toxic to Sitophilus oryzae L. 1763 (Coleoptera: Curculinidae), 1.073 strains of B. thuringiensis from parts of Brazil were used. Genetic material was extracted with InstaGene Matrix kit, used for the amplification of sequences in Polymerase chain reaction (PCR), and viewed in 1.5% agarose gel. The gene cry35Ba class was represented by 60 B. thuringiensis isolates (5.6%), which were then subjected to bioassays with S. oryzae larvae. Among the isolates studied, four caused more than 50% mortality in pathogenicity tests, and the isolates 544 and 622 were the most virulent, as determined by CL50 estimates. The four toxic isolates had spherical, bi-pyramidal and cuboid crystals, and a 44-kDa protein was found in sodium dodecyl sulphate - polyacrylamide gel electrophoresis (SDS-PAGE), which coded for the product of cry35Ba genes. These data demonstrate the potential of B. thuringiensis for the management of S. oryzae larvae.