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.
Insect pests introduced in eucalyptus plantations in Brazil are mostly of Australian origin, but native microorganisms have potential for their management. High quality biopesticide production based on entomopathogenic fungi depends on adequate technologies. The objective of this study was to evaluate Mycoharvester® equipment to harvest and separating particles to obtain pureMetarhizium anisopliaeconidia to manageThaumastocoris peregrinusCarpintero & Dellapé, 2006 (Hemiptera: Thaumastocoridae). The Mycoharvester® version 5b harvested and separatedM.anisopliaespores. The pure conidia were suspended in Tween 80® (0.1%) and calibrated to the concentrations of 1 x 106, 107, 108and 109conidia/ml to evaluate the pathogenicity, lethal concentration 50 and 90 (LC50, LC90) and lethal time 50 and 90 (LT50, LT90) of this fungus toT.peregrinus. This equipment harvested 85% of the conidia from rice, with production of 4.8 ± 0.38 x 109conidia/g dry mass of substrate + fungus. The water content of 6.36% of the single spore powder (pure conidia) separated by the Mycoharvester® was lower than that of the agglomerated product. The product harvested at the concentrations of 108and 109conidia/ml caused high mortality toT.peregrinusthird instar nymphs and adults. The separation of conidia produced by solid-state fermentation with the Mycoharvester® is an important step toward optimizing the fungal production system of pure conidia, and to formulate biopesticides for insect pest management.
The parasitoid Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae), entomopathogenic fungi, and chemical insecticides are the main strategies to manage the eucalypts pest Glycaspis brimblecombei Moore. The objective of this study was to isolate and to identify entomopathogenic fungi, collected from Bemisia tabaci Gennadius adults in soybean and tomato crops, and from soil samples in eucalypts, soybean, and native forest areas to evaluate their potential to manage G. brimblecombei. Twelve Beauveria and Cordyceps isolates were selected and compared with the commercial products Boveril Beauveria bassiana Bals. (Hypocreales: Cordycipitaceae), Metarril Metarhizium anisopliae Metschn. (Hypocreales: Clavicipitaceae), and Octane Cordyceps fumosorosea Wize (Hypocreales: Cordycipitaceae) and their respective strains. The fungal isolates were diluted in 0.1% aqueous Tween 80 at a concentration of 1.0 × 108 conidia/ml and sprayed on the G. brimblecombei nymphs with or without lerps. Pest mortality was higher and the TL50 and TL90 lower with the isolates LCBPF 11 C. javanica Frieder. & Bally (Hypocreales: Cordycipitaceae), LCBPF 12 (C. fumosorosea), and LCBPF 67 (C. fumosorosea) from B. tabaci adults. Fungi of the genera Beauveria and Cordyceps developed and caused high mortality of G. brimblecombei nymphs with lerps. The B. bassiana, C. cateniannulata Liang (Hypocreales: Cordycipitaceae), C. fumosorosea, C. javanica, and M. anisopliae isolates showed potential to manage G. brimblecombei. The lerp of this insect enhances entomopathogenic fungus development as a source of inoculum accelerating G. brimblecombei nymph mortality. Entomopathogenic fungi isolated from insects and soils are effective against G. brimblecombei and the presence of the lerp of this insect increases the effectiveness of its control.
The total area of forest crops in Brazil is 9.55 million hectares, of which 7.5 million hectares are Eucalyptus. These crops are the most productive in the world, but may suffer losses due to exotic pests, including Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae) found in Brazil since 2003. Interactions between Eucalyptus plants and insect pests may led to the selection of resistant genotypes. Eucalyptus species are either susceptible or resistant to this pest group, but the damage they suffer needs to be evaluated. The objective was to determine possible leaf anatomy indicators of different Eucalyptus species associated with G. brimblecombei infestations, focusing on plant resistance to this pest. The study was carried out with Eucalyptus camaldulensis, Eucalyptus grandis, Eucalyptus saligna and Eucalyptus urophylla saplings infested or not by G. brimblecombei eggs and nymphs. Eighteen anatomical characteristics of the leaves of these plants were analyzed. The number of stomata on the adaxial and abaxial sides and the glandular area in the central leaf vein are associated with greater or lesser infestation by G. brimblecombei in the Eucalyptus genotypes.
Cleruchoides noackae Lin & Huber (Hymenoptera: Mymaridae) was imported to Brazil in 2012, to manage the exotic pest Thaumastocoris peregrinus Carpintero & Dellapé (Hemiptera: Thaumastocoridae), which has been damaging eucalyptus plantations. Knowledge of the thermal requirements and the fertility life table of C. noackae is important to improve mass rearing methods for this parasitoid and the effectiveness of its release to manage T. peregrinus. The objective was to evaluate the development period, thermal requirements and the fertility life table of C. noackae at different temperatures. The egg-adult period of this parasitoid varied from 43 to 14 days at 15 °C and 30 °C, respectively. The emergence of C. noackae adults was higher at 15 °C, 18 °C, 21 °C and 24 °C than at 30 °C. Female and male C. noackae need 226.75 and 230.41 degree-days and temperatures higher than 10.06 °C and 9.90 °C, respectively, to complete egg-adult development. The number of parasitized eggs per C. noackae female was higher at 21 °C, 24 °C and 27 °C, with 5.82, 7.73 and 5.50 eggs, respectively, than at 30 °C (0.45). Cleruchoides noackae longevity was greater at 15 °C, 21 °C and 24 °C. The net reproductive rate of the parasitoid was higher at 21 °C and 24 °C than at 30 °C, 3.05, 4.70 and 0.16, respectively. The finite rate of increase of C. noackae was greater at 21 °C, 24 °C and 27 °C, than at 30 °C and the intrinsic rate of increase was negative at 30 °C, −0.100. The temperatures 21 °C and 24 °C and from 18 °C to 27 °C are the most adequate for the reproduction and population increase of C. noackae parasitizing eggs of T. peregrinus, respectively.
Soils present high fungal diversity, including entomopathogenic species. These fungi are used in pest control, providing easy production, multiplication, application, and dispersion in the field. The objective of the present study was to evaluate entomopathogenic fungal diversity in soils from eucalyptus and soybean crops and natural forest areas. These fungi were isolated using the “Bait Method” with Tenebrio molitor (Linnaeus, 1758) (Coleoptera: Tenebrionidae) larvae from 10 soil samples per area, collected at 10 cm deep in a zig-zag pattern. The isolated entomopathogenic fungi were cultivated in Petri dishes using PDA medium and their mycelia separated after seven days of incubation in a BOD-type chamber. Species of Aspergillus, Beauveria, Cordyceps, Fusarium, Metarhizium, Penicillium and Purpureocillium were identified. The “Bait Method” with T. molitor larvae is efficient to isolate entomopathogenic fungi with higher diversity from soils of the natural forest than the cultivated area.