11 research outputs found
Distribution Pattern Of Aphis Gossypii And Its Coccinellid Predator Menochilus Sexmaculatus In The Chilli Ecosystem Pola Distribusi Aphis Gossypii Dan Predator Koksinelid Menochilus Sexmaculatus Pada Ekosistem Cabai
Studi tentang pola penyebaran Aphis gossypii Glover (Homoptera: Aphididae) predator Menochilus sexmaculatus Fabricius (Coleoptera: Coccinellidae) dilakukar ekosistem cabal di Kebun Percobaan Universiti Putra Malaysia. Hasil penelitian menunjul bahwa penyebaran M. sexmaculatus berkorelasi positif dengan penyebaran mangsa Penyebaran lateral clan vertical A. gossypii serta M. sexmaculatus dikategorikan sebagai penyebaran mengelompok.
Kata kunci: Aphis gossypii, Menochilus sexmaculatus, distribus
Evaluation of the virulence of entomopathogenic fungus, Isaria fumosorosea isolates against subterranean termites Coptotermes spp. (Isoptera: Rhinotermitidae)
The entomopathogenic fungus Isaria fumosorosea Wize, formerly known as Paecilomyces fumosoroseus is reported as a promising biocontrol agent for controlling subterranean termites, particularly those belonging to the family Rhinotermitidae. In Malaysia, the family Rhinotermitidae includes two species of subterranean termites with extremely high economic importance; namely Coptotermes curvignathus Holmgren, and the Asian Subterranean Termite (Coptotermes gestroi Wasmann). To comprehend the potential control of this soil-dwelling fungus against these subterranean termites in Malaysia, an investigation was carried out by testing the pathogenecity of 11 isolates against these termite species. All isolates showed pathogenic potential against the termite (Mortality rate of C. curvignathus: 84.4%; C. gestroi: 67.3%). Isolate PF49 was the most effective against both species of termites and was further tested for its virulence and mycosis. The LC50 values of PF49 against C. curvignathus and C. gestroi were 7.55 × 103 and 1.09 × 102 conidia/ml, respectively. The average number of days required to complete the mycosis process in C. curvignathus and C. gestroi were 4.7 and 8 days, respectively. These fungi are believed useful for protecting living trees, plants, wood, wood structures, and other cellulosic materials susceptible to termite infestation and damage
Distribution Pattern of Aphis Gossypii and Its Coccinellid Predator Menochilus Sexmaculatus in the Chilli Ecosystem
A study on the distribution pattern of Aphis gossypii Glover and its coccinellid predator, Menochilus sexmaculatus Fabricius, was conducted in a chilli ecosystem at the experimental field of Universiti Putra Malaysia. The study had revealed that distribution of M. sexmaculatus positively correlated with its prey distribution. The patterns of lateral and vertical distribution of A. gossypii and M. sexmaculatus were categorized as a clumped pattern
Colonização e lesão em fêmeas ingurgitadas do carrapato Rhipicephalus sanguineus causadas pelo fungo Metarhizium anisopliae Colonization and lesions on engorged female Rhipicephalus sanguineus, caused by Metarhizium anisopliae
O presente trabalho teve como objetivo verificar a forma de penetração do fungo Metarhizium anisopliae [METSCH. (SOROKIN, 1883)] em carrapatos da espécie Rhipicephalus sanguineus (LATREILLE, 1806), assim como as lesões infringidas nos tecidos internos do ácaro. A forma de aderência e penetração do fungo foi estudada através da microscopia eletrônica de varredura e a ação do fungo nos tecidos internos avaliada em secções histológicas convencionais. Para observação destes eventos, realizaram-se infecções experimentais em 11 grupos de fêmeas ingurgitadas do carrapato R. sanguineus contendo 12 fêmeas ingurgitadas cada. Para tal, as fêmeas ingurgitadas foram banhadas durante 3 minutos, sob agitação manual, em suspensão com concentração 108 conídios/mL. No caso dos grupos controle o banho foi realizado apenas no veículo da suspensão. Os carrapatos foram processados para histopatologia e microscopia eletrônica em diversos tempos após a infecção, a saber: 1 e 18h, e um, dois, três, quatro, cinco, seis, sete, nove e onze dias. Observou-se que a maior parte dos conídios germinou em até 18h após a inoculação e que o fungo penetrou no ácaro através do tegumento 48h após a infecção. Após a penetração, o fungo invadiu o corpo do hospedeiro promovendo uma colonização difusa, sem preferência aparente por tecidos específicos. Dentre as lesões nos tecidos internos do ácaro, ressalta-se o rompimento da parede intestinal e vazamento do conteúdo para a hemocele. A morte do hospedeiro ocorreu entre 96 e 120h pós-infecção, e a esporulação do patógeno sobre o cadáver do ácaro iniciou-se em torno de 120 a 144h pós-infecção. Espera-se, com este trabalho, contribuir para o desenvolvimento e viabilização de técnicas de controle biológico dos carrapatos por fungos como alternativa ao uso de acaricidas.<br>The objective of this work was to verify the penetration of the fungus Metarhizium anisopliae [METSCH. (SOROKIN, 1883)], in to the Rhipicephalus sanguineus ticks (LATREILLE, 1806), as well as the lesions caused in the tissues of the acarus. The form of adherence and penetration of the fungus in the deep tissue was studied through scanning microscopy and the fungus action on the internal tissues was evaluated in conventional hystological sections. In order to evaluate these events, experimental infestations were conducted in 11 engorged females groups of the tick R. sanguineus, containing 12 engorged females in each. Aiming this goal the engorged females were submited to a bath in a conidial suspension in a concentration of 108 conidia/mL during three minutes under manual agitation. In case of control groups the bath was done only in the suspension vehicle. Ticks were processed for histological and scanning microscopy surveys at different intervals after the infection: 1 and 18h and one, two, three, four, five, six, seven, eight, nine and eleven days. It has been observed that the major part of the conidians have germinated within 18h after the inoculation and that the fungus the penetrated the acarus body, trough it´s tegument 48h after the infection. After the penetration the fungus colonized the tick’s body in a diffuse manner, without any preference for a specific tissue. Among the lesions caused by the fungus, rupture of the tick’s intestinal wall and the dispersion of the fluid into the hemocel were the most outstanding features. Death of the host occurred 96h pos-infection and the sporulation of the pathogen over the dead acarus began 120 to 144h pos-infection. This work aims to contribute to the establishement of techniques for biological control of the ticks by fungus as an ecological alternative for acaricides