Liriomyza huidobrensis (Blanchard) and Liriomyza sativae (Blanchard) are important pests of vegetable crops in Indonesia and are likely to spread to neighboring countries. Three pesticides (dimehypo, abamectin, and cyromazine) are currently used to control these pests, but there is little information on their effectiveness against field populations and on their impact on parasitoids controlling Liriomyza species. The toxicity of these chemicals to L. huidobrensis and three common parasitoids (Hemiptarsenus varicornis Gerault, Opius sp., and Gronotoma micromorpha Perkins) was therefore evaluated in Indonesia with mortality laboratory assays. All three chemicals were effective against larvae of three populations of L. huidobrensis with different histories of chemical exposure. Dimehypo caused mortality in adult Opius sp., G. micromorpha, and H. varicornis, whereas abamectin was toxic only at concentrations substantially higher than the field rate. Cyromazine did not influence survival of the parasitoids. A commonly used fungicide, mancozeb, had no impact on parasitoid mortality. Trials were repeated with a strain of H. varicornis from Australia and a different parasitoid (Diglyphus isaea) recently found in Australia. Neither parasitoid was influenced by mancozeb or cyromazine. Abamectin applied at field rates caused some mortality among the adults of both species, but was less toxic than chlorpyrifos. Abamectin produced lower LC50s against Australian H. varicornis than against Indonesian H. varicornis. These results suggest that cyromazine can be incorporated into Liriomyza control programs in Indonesia that conserve parasitoids, whereas dimehypo and abamectin need to be used cautiously. Local Australian parasitoids should help control L. huidobrensis as long as only cyromazine and nontoxic fungicides are applied.

Four new metabolites, aglacins A-D (1-4), were identified from the methanol extract of the stem bark of Aglaia cordata. These compounds represent a new class of aryltetralin cyclic ether lignan. The structure of aglacin A (1) including the absolute configuration was elucidated by interpretation of spectral data, X-ray crystal structure determination, and employing the modified Mosher's method. In addition, three other derivatives, aglacins B-D (2-4), were isolated and identified by spectral means.

Crocidolomia pavonana merupakan hama penting pada tanaman sayuran Brassicaceae. Insektisida nabati merupakan salah satu alternatif potensial untuk mengendalikan hama tersebut. Penelitian ini bertujuan menentukan tingkat toksisitas ekstrak etil asetat buah Piper aduncum (EtPa), ekstrak metanol buah Sapindus rarak (MeSr), ekstrak air buah S. rarak (AqSr), serta campuran ekstrak EtPa + MeSr dan ekstrak EtPa + AqSr terhadap larva C. pavonana. Setiap ekstrak diuji terhadap larva instar II C. pavonana dengan metode celup daun. Pada taraf LC95 - 72 jam setelah perlakuan (JSP), ekstrak EtPa lebih beracun terhadap larva C. pavonana daripada ekstrak MeSr dan AqSr, masing-masing sebesar 14,5 dan 12,8 kali. Pada taraf LC95, campuran ekstrak EtPa + MeSr (1 : 10, w/w) sekitar 1,64 kali lebih beracun terhadap larva C. pavonana daripada campuran ekstrak EtPa + AqSr (1 : 10, w/w). Berdasarkan indeks kombinasi pada pengamatan 48, 72, dan 96 JSP, campuran ekstrak EtPa + MeSr pada taraf LC50 serta campuran ekstrak EtPa + AqSr pada taraf LC50 dan LC95 bersifat aditif, sedangkan campuran ekstrak EtPa + MeSr pada taraf LC95 bersifat sinergistik lemah. Selain mengakibatkan kematian, perlakuan dengan semua ekstrak uji juga menghambat perkembangan larva C. pavonana dari instar II ke instar IV. Dengan demikian, ekstrak EtPa, MeSr, AqSr, serta campuran ekstrak EtPa dan S. rarak berpotensi untuk digunakan sebagai salah satu alternatif dalam pengendalian hama C. pavonana.

An examination of insect resistance was determined by several steps, i.e. standard sensitivity, resistance diagnosis, and determination of resistance level. Each phase was tested with feeding and residue contact methods at glass tube. Resistance ratio (RR) was determined by comparing LC50 value of field population with standard population. Field population of C. pavonana was classified resistant if it had RR 5 4. Biochemistry analysis of resistance was conducted to population of C. pavonana showing resistance to prophenophos insecticide. The activity analysis of acetylcholine esterase (ACHE), esterase, and Glutation Stransferase was done with spectrophotometer method. Insect which are resistant to prophenophos insecticide was tested for its sensitivity to Barringtonia asiatica seed extract. Result indicated that C. pavonana population from Pengalengan showed resistance to prophenophos synthetic insecticide. Using contact test, the highest resistance ratio value was 4.04, while by feeding assay the RR was 2.78. The study on biochemical resistance mechanisms of each field population of C. pavonana showed various activities of enzymatic detoxification. This could be due to the difference in the kind of insecticides exposed to each field population of C. pavonana. Since RR value from the contact test was higher than that of the feeding test, the resistance development of C. pavonana to synthetic insecticides was probably caused by physiological and biochemical changes in insect cuticle rather than the activity of detoxification enzyme. Methanolic seed extract of B. asiatica can be used as an alternative of resistance management of C. pavonana to prophenophos synthetic insecticide.

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