Isolation and molecular characterization of Cordyceps sp. from Bemisia tabaci (Hemiptera: Aleyrodidae) and pathogenic to Glycaspis brimblecombei (Hemiptera: Aphalaridae).

The Brazilian forestry sector stands out for its technology, forestry management practices, social and environmental responsibility and, mainly, for its high productivity and exotic pests can reduce it. The red gum lerp psyllid Glycaspis brimblecombei (Moore, 1964) (Hemiptera: Aphalaridae) is an important pest in Eucalyptus plantations. The parasitoid Psyllaephagus bliteus (Riek, 1962) (Hymenoptera: Encyrtidae), predatory bugs and entomopathogenic fungi such as Beauveria bassiana and Metarhizium anisopliae are the natural enemies and used in the biological control of the red gum lerp psyllid. The use of entomopathogenic fungi against exotic pests is increasing in the forestry sector and the prospecting and identification of fungus isolates is important for integrated pest management. The objective of this work was the isolation and molecular identification of Cordyceps spp. And to evaluate the pathogenicity of isolates, obtained from Bemisia tabaci (Gennadius, 1889) (Hemiptera: Aleyrodidae) adults, against to the red gum lerp psyllid G. brimblecombei. The fungi were isolated from B. tabaci adults found in soybean and tomato crops and molecularly identified. The conidia obtained were suspended in solution with Tween 80 (0.1%) at a concentration of 1.0 × 108 conidia/mL and sprayed on ten G. brimblecombei nymphs per Eucalyptus leaf cut and placed on a hydroretentive gel inside per Petri dishes as a replication. The number of dead insects was quantified, daily, for seven days, and transferred to humid chambers. Cordyceps javanica (LCBPF 11) and C. fumosorosea (LCBPF 12 and LCBPF 63) were identified with a molecular analysis and all isolates were pathogenic to the insects and indicates that they could be used to manage G. brimblecombei and adds to reports that, normally, fungi cause greater mortality on insects of the same order as that from which they were isolated.

Preference of red mite Tetranychus ludeni Zacher (Acari: Tetranychidae) to sweet potato genotypes / Preferência do ácaro vermelho Tetranychus ludeni Zacher (Acari: Tetranychidae) por genótipos de batata-doce

Abstract Tetranychus ludeni damages the sweet potato. Pest development can vary between plant genotypes. The objective was to identify the preference of Tetranychus ludeni for Ipomoea batatas genotypes, from the germplasm bank at the Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Natural infestations of this mite were observed on 54 sweet potato genotypes in potted, in a greenhouse. Three mite-infested leafs of each genotype were collected and analyzed. The red mite showed different population density rate in genotypes. The BD 29 genotype was found to be highly susceptible, the BD 08, BD 57, BD 17 and Espanhola genotypes were moderately susceptible, and the others forty-nine genotypes showed low susceptibility to the mite.

Resumo Tetranychus ludeni danifica plantas de batata-doce. O desenvolvimento de pragas pode variar entre genótipos de plantas. O objetivo foi identificar a preferência de T. ludeni para genótipos de Ipomoea batatas do banco de germoplasma da Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Infestações naturais deste ácaro foram observadas em 54 genótipos de batata doce plantados em vasos e mantidos em estufa. Três folhas infestadas por ácaros, de cada genótipo, foram coletadas e analisadas. Tetranychus ludeni mostrou diferentes taxas de crescimento populacional entres os genótipos. O genótipo BD 29 foi altamente suscetível, os BD 08, BD 57, BD 17 e Espanhola foram moderadamente suscetíveis e os outros 49 genótipos mostraram baixa suscetibilidade ao ácaro.

Preference of red mite Tetranychus ludeni Zacher (Acari: Tetranychidae) to sweet potato genotypes.

Tetranychus ludeni damages the sweet potato. Pest development can vary between plant genotypes. The objective was to identify the preference of Tetranychus ludeni for Ipomoea batatas genotypes, from the germplasm bank at the Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM). Natural infestations of this mite were observed on 54 sweet potato genotypes in potted, in a greenhouse. Three mite-infested leafs of each genotype were collected and analyzed. The red mite showed different population density rate in genotypes. The BD 29 genotype was found to be highly susceptible, the BD 08, BD 57, BD 17 and Espanhola genotypes were moderately susceptible, and the others forty-nine genotypes showed low susceptibility to the mite.