Edmilson Jacinto Marques

Fitofagia de Podisus nigrispinus em algodoeiro e plantas daninhas

This work evaluated the effect of six weeds and cotton plants on predatory stinkbug Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) development, reproduction and survival under partial prey scarcity, three days feeding intervals, and total absence of prey. Nymphal developmental periods under partial prey scarceness with three days of feeding intervals were higher on Ricinus communis and lower on Bidens pilosa. Partial prey scarcity did not affect nymphal viability, adult female weight and reproductive characteristics, but male weight and female longevity were reduced in Desmodium tortuosum and R. communis, respectively. Podisus nigrispinus showed better performance on Amaranthus hybridus, D. tortuosum and R. communis based on the life table parameters. Nymphs reared under total absence of prey lived longer on Ageratum conyzoides, B. pilosa, D. tortuosum and Euphorbia heterophylla; however, they did not live beyond the third instar. Longevity of P. nigrispinus females was improved depending on the plant available ranging from 15.7 days on Gossypium hirsutum to 29.8 days on A. conyzoides. The plant availability under total absence of prey, however, was not sufficient to endure female sexual maturation and egg production.

Seleção de isolados de fungos entomopatogênicos para o controle de Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) e sua compatibilidade com alguns inseticidas usados na cultura do tomateiro

The activity of Metarhizium anisopliae and Beauveria bassiana towards eggs and larvae of Tuta absoluta (Meyrick) was evaluated. Our data showed that the isolates were pathogenic to both developmental stages tested and the eggs were more susceptible than the 1st instars. The isolates URPE-6 and URPE-19 of M. anisopliae were more pathogenic to eggs and larvae, respectively. The compatibility of these two isolates with the insecticides chlorfenapyr, spinosad, indoxacarb, abamectin, and neem were evaluated. Spinosad and indoxacarb were compatible with the two M. anisopliae isolates in all tested concentrations. At the average recommended concentration, chlorfenapyr was compatible to URPE-6 and abamectin to UFPE-19. The use of entomopathogenic fungi associated with compatible insecticides may be a useful alternative to control T. absoluta.

Ultrastructure of Tuta absoluta parasitized eggs and the reproductive potential of females after parasitism by Metarhizium anisopliae.

Among the microorganisms used in biological control, the muscadine fungus Metarhizium anisopliae (Metsch.) Sorok. is produced and formulated world wide aiming to control pests from several agricultural crops. This work evaluated effects of M. anisopliae isolate UFRPE-6 on the fecundity and mortality of Tuta absoluta (Lepidoptera: Gelechiidae) females and the mechanism of infection on eggs. The infection of the females by the fungus did not affect their oviposition and fecundity; however it affected the survival with total and confirmed mortality of 54.2% and 37.14%, respectively. The eggs were treated with suspension at concentration of 10(6)conidia/mL. The analysis under scanning electron microscopy showed that conidia germination and penetration processes in the eggs of T. absoluta started within the period of 6h after the inoculation. Several hyphal bodies were observed from 12h and an intense extrusion of the mycelium covering all the external surface of the eggs 72h after inoculation. Despite its moderate activity in adults, the isolate URPE-6 of M. anisopliae showed promising in the control of T. absoluta due to its pathogenicity and virulence to eggs from this pest.

Suscetibilidade de Plutella xylostella (L.) (Lepidoptera: Plutellidae) aos fungos Beauveria bassiana (Bals.) Vuill. e Metarhizium anisopliae (Metsch.) Sorok

An initial screening was undertaken using the isolates ESALQ 447, ESALQ 760, ESALQ 900, ESALQ 634, IPA-205 and ESALQ 760 of B. bassiana, and ESALQ E9, IPA-207, ESALQ 860, IPA-204 and UFPE 3027 of M. anisopliae at the concentration of 108 conidia/ml for the diamondback moth (DBM) second instar. All isolates tested caused DBM larval mortality ranging from 70% to 96%, except the M. anisopliae isolate UFPE 3027, which resulted in a mortality of 26%. Based on this survey the isolates ESALQ 634 and ESALQ 447 of B. bassiana and IPA-207 and ESALQ E9 of M. anisopliae were chosen and assessed at the concentrations 105, 106, 107 and 108 conidia/ml for DBM second instar. These selected isolates at concentrations higher than 106 conidia/ml caused DBM larval mortality ranging from 58% to 96%. The mean lethal time (LT50) for DBM second instar were 1.1 and 4.3 days, and 0.7 and 5.8 days for B. bassiana isolates ESALQ 634 and ESALQ 447 and M. anisopliae isolates IPA-207 and ESALQ E9, respectively. Based on the lethal concentrations (LC50) the isolates IPA-207 and ESALQ E9 were seven times more virulent to DBM second instar than B. bassiana isolates ESALQ 634 and ESALQ 447. These results showed that DBM larvae were more susceptible to M. anisopliae than to B. bassiana and that M. anisopliae isolates IPA-207 and ESALQ E9 may be a valuable component for the integrated management of DBM larvae.

Associação do óleo de mamona com Beauveria bassiana no controle da traça-das-crucíferas

Abstract – The objective of this work was to evaluate the efficiency,the stability, the application mode and the compatibility between castor bean oil and the entomopathogenic fungus Beauveria bassiana , for diamondback moth ( Plutella xylostella ) control. In the firstexperiment, the efficiency,the stability after 70 days of storage, and the application mode of castor bean oil were evaluated. In the second one, the compatibility of castor bean oil with B. bassiana was evaluated. The insecticidal activity of the castor bean oil is unstable over time. The castor bean oil is compatible with B. bassiana against P. xylostella .Index terms: Beauveria bassiana , Plutella xylostella , Ricinus communis , entomopathogenic fungus. A traca‑das‑cruciferas, Diaphania nitidalis Plutella xylostella (L.) (Lepidoptera: Plutellidae), e a praga mais importante de plantas da familia Brassicaceae. Para o seu controle, utilizam-se basicamente inseticidas (Castelo Branco & Medeiros, 2001). No entanto, outros metodos para o controle desta praga tambem devem ser avaliados, entre os quais, a utilizacao de fungos entomopatogenicos, como

Interação de Metarhizium anisopliae (Metsch.) Sorok., Beauveria bassiana (Bals.) Vuill. e o parasitóide Oomyzus sokolowskii (Kurdjumov) (Hymenoptera: Eulophidae) sobre larvas da traça-das-crucíferas, Plutella xylostella (L.) (Lepidoptera: Plutellidae)

Chemical insecticides are broadly applied to control diamondback moth, Plutella xylostella (L.). Diamondback moth is a major pest of cruciferous worldwide, and resistance of this pest to insecticide has been often reported. Thus, this research investigated the interactions among the fungi Metarhizium anisopliae (Metsch.) Sorok., Beauveria bassiana (Bals.) Vuill., and the larval-pupal parasitoid Oomyzus sokolowskii (Kurdjumov) before and after application of the fungi on DBM larvae offered to the parasitoid. The experiment was carried out at 26+/-l degreeC, 75+/- 5% RH and 12h photophase using a completely randomized design, with eight treatments with six replications each. The isolates E9 of M. anisopliae and ESALQ 447 of B. bassiana, were used at the concentration of 10(7) conidia ml(-1). The results showed that M. anisopliae and B. bassiana reduced the parasitism of P. xylostella by O. sokolowskii. Additive effects were found on the mortality of P. xylostella with the different combinations among the fungi and parasitoid, except for the treatment B. bassiana inoculated 24h before exposition of the larvae to O. sokolowskii. The isolates were more efficacious when applied after exposition of the larvae to the parasitoid. The efficiency of O. sokolowskii was negatively influenced by the presence of the fungi, mainly when the fungi were applied 24h before diamondbacks larvae were exposed to the parasitoid. The association of the fungi with the parasitoid presents potential to be tested in field. The use of these natural enemies in the integrated management of P. xylostella may economically improve the cabbage productive system, especially for organic farming.

Efeito de plantas daninhas e do algodoeiro no desenvolvimento, reprodução e preferência para oviposição de Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae)

This study investigated the effects of six weeds [Amaranthus hybridus L., Desmodium tortuosum (Sw.), Euphorbia heterophylla L., Ageratum conyzoides L., Bidens pilosa L., Ricinus communis L.] and the cotton plant Gossypium hirsutum L. CNPA Precocious 1 on Podisus nigrispinus (Dallas) life history characteristics and oviposition behavior. The study begun with P. nigrispinus eggs placed on plants and caged throughout up to female death. Egg production and selected plant for oviposition by P. nigrispinus were investigated caging mated females on weeds and cotton plants simultaneously. Nymphal development of P. nigrispinus was shorter on D. tortuosum and longer on A. hybridus. Nymphal viability was not affected by any species of plant studied. Nymphs reared on R. communis produced females weighting less compared to the other plant species. The weed A. conyzoides promoted higher female fecundity compared to those females reared on D. tortuosum, E. heterophylla and R. communis. The demographic parameters net reproductive rate (Ro) and mean generation time (T) of P. nigrispinus were higher for females reared on A. conyzoides, while the intrinsic rate of population increase (rm) and finite rate of increase (l) suggest that better performance of the predator will be yielded on B. pilosa. The weed plants A. hybridus and B. pilosa were significantly preferred by P. nigrispinus females to lay eggs. These results suggest that the weeds A. conyzoides, B. pilosa and A. hybridus can benefit the colonization and maintenance of P. nigrispinus in the cotton ecosystem by phytophagy.

Potencial de isolados de Metarhizium anisopliae e Beauveria bassiana e do óleo de Nim no controle do pulgão Lipaphis erysimi (Kalt.) (Hemiptera: Aphididae)

This work aimed to determine the efficiency of the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana to control the aphid Lipaphis erysimi (Kalt.) (Hemiptera: Aphididae) in kale Brassica oleracea var acephala D.C., as well as their compatibility with a neem oil formulation (Neemseto). Ten isolates of both fungi were tested and the most pathogenic ones were B. bassiana CG001 and M. anisopliae CG30 with 90% and 4.4 days, and 64% and 3.8 days of mortality and median lethal time, respectively. Bioassays with neem at concentrations of 0.5, 1.0 and 2.0% were done either by leaf discs dipping or spraying the aphids on the leaf discs. The neem spraying treatment at 2.0% provided 90% mortality. The use of B. bassiana isolate CG001 or M. anisopliae isolate CG30 with neem at 0.125, 0.25, and 0.5%, demonstrated that these isolates could have their spore viability or colony growth affected when exposed to neem concentrations higher than 0.25%. In absolute values, the isolates B. bassiana CG001 and M. anisopliae CG30 are the most virulent to L. erysimi, and could be utilized in the management of this pest.

Selection of Beauveria bassiana (Bals.) Vuill. and Metarhizium anisopliae (Metsch.) Sorok. for the control of the mite Mononychellus tanajoa (Bondar)

O acaro verde Mononychellus tanajoa (Bondar) (Acari: Tetranychidae) causa desfolhamento em mandioca Manihot esculenta Crants, proporcionando perdas na producao. Esse trabalho objetivou selecionar isolados dos fungos Beauveria bassiana (Bals.) Vuill. e Metarhizium anisopliae (Metsch.) Sorok. para utilizacao no controle desse acaro. Foram utilizados dez isolados de B. bassiana e dez isolados de M. anisopliae , sobre femeas adultas de M. tanajoa. A percentagem de mortalidade total por B. bassiana variou de 13,0 a 97,0%, com mortalidade confirmada de 9,0 a 91,0%, e o tempo letal (TL50) variou entre 4,2 e 17,0. Os isolados de M. anisopliae, provocaram 12,0 a 45,0% de mortalidade total e 8,0 a 45,0% de mortalidade confirmada e TL50 entre 8,6 e 19,8 dias. Estimaram-se os valores das concentracoes letais (CL50) de 3,93 . 106 conidios mL-1 e 7,44 . 108 conidios mL-1, para os isolados 645 de B. bassiana e CG 321 de M. anisopliae, respectivamente. O isolado 645 de B. bassiana foi mais eficiente, sugerindo sua utilizacao em programas de controle biologico do acaro verde da mandioca.

Selection of Metarhizium anisopliae (Metsch.) and Beauveria bassiana (Bals.) isolates to control Alabama argillacea (Huebner) caterpillars

The cotton leafworm, Alabama argillacea (Huebner, 1818) (Lepidoptera: Noctuidae), is considered to be one of the key pests in herbaceous cotton (Gossypium hirsutum L. r. latifolium Hutch) cropping, with constant occurrence in all cotton-growing states of Brazil. In this study Metarhizium anisopliae and Beauveria bassiana isolates were screened and evaluated for pathogenicity against Alabama argillaceae. Initially, a screening of ten isolates of each fungus in a concentracion of 108 conidia mL-1, was carried out on 3rd instar larvae of A. argillacea. Further studies were conducted to determine the pathogenicity and virulence of six and seven isolates of M. anisopliae and B. bassiana, respectively, against 3rd instar larvae of A. argillacea and using the concentrations of 106, 107, 108, and 109 conidia mL-1. The experiments were carried out in Recife, PE, Brazil, at 27 ± 2oC, RH 70 ± 5% and a photophase of 12 hours. Mortalities caused by M. anisopliae isolate at the different concentrations ranged from 4.5 to 91.2%, the highest mortality percentage being found for the isolate 1189 at 109 conidia mL-1. The isolate 645 of B. bassiana caused the highest mortality at the highest concentration, followed by isolates 634, 604, and IPA 198. The lowest lethal time for B. bassiana and M. anisopliae, was achieved by the isolates 483 (4.1 days) and 1189 (2.0 days), respectively. The isolates 1189, 1022 e 866 of M. anisopliae and 483, IPA198 and 604 of B. bassiana, at 108 e 109 conidia mL-1 are promissing for use the integrated control of A. argillacea larvae, but M. anisopliae seems more effective.