Theresearch wasaimed to assess effect of some concentrations of lemon grass stem extract to C. binotalis larvae. The advantage of the research was to give information the use lemon grass stem extract as a botanical insecticide to control C. binotalis larvae. The result showed that after application of the lemon grass stem extract, the C. binotalis larvae showed symptoms such as inactive of eating, inactive of movement and eventually death of larvae C. binotalis.The death of larvae was showing changing of color at dorsal and ventral. The color at the dorsal became pale yellow and the color at ventral turned to light brown.The death larvae subsequently were hardened and the entire body the larvae were blackish brown.The percentage of C. binotalis larvae mortality increased when the concentration of lemon grass stem extract was also increased.Concentration 80 g/50 ml resulted 95 % death of total tested larvae. It could be concluded thatlemon grass stem extract can be used to control larvae of C.binotalis on cabbage. ABSTRAKPenelitian ini bertujuan untuk mengetahui pengaruh beberapa konsentrasi ekstrak batang serai terhadap larva C. binotalis. Manfaat dari penelitian ini adalah untuk memberikan informasi tentang penggunaan ekstrak batang serai sebagai insektisida botani untuk mengendalikan larva C. binotalis. Gejala kematian larva C. binotalis setelah aplikasi ekstrak batang serai pada awalnya larva kelihatan gelisah, tidak aktif makan kemudian menjadi tidak aktif bergerak dan akhirnya mati. Larva yang mati terjadi perubahan warna, pada bagian dorsal berwarna kuning pucat dan bagian ventral berwarna coklat muda dan lama kelamaan seluruh tubuh mengeras dan berwarna coklat kehitaman. Hasil penelitian menunjukan bahwa persentase mortalitas larva C binotalis meningkat seiring dengan meningkatnya konsentrasi ekstrak batang serai yang diaplikasikan. Pada konsentrasi ekstrak batang serai 80g/ml menyebabkan mortalitas sebesar 95% dari keseluruhan larva uji. Berdasarkan hasil ini, ekstrak batang serai dapat digunakan untuk mengendalikan larva C. binotalis pada kubis.

Aquatic insects are one of the organisms that are used in determining water contamination. Aquatic insects are sensitive to the presence of waste dumped in the river and some are resistant to such waste. One of insect resistant waste is Chironomidae. The research objective was to determine aquatic insect species, population abundance by calculating indices diversity and biotic index. Aquatic insects in the lake watershed Tondano were collected by kicks and Hand Picking. Result showed that seven orders, theerteen families and sixteen species had been identified. The number of highest aquatic insect was found in Noogan which were 13 species, whereas in karondoran were 9 species. Aquatic insects were identified including, Heptagenia sp, sp Baetis sp, Caenis sp., Hydropsyhe, sp and Chrironomidae. The highest aquatic insect populations were collected in Karondoran followed by Winebetan and Noogan. The highest diversity index of aquatic insects was found in Winebetan whereas the lowest was in Karondoran. The lowest value of the biotic index was identified in the region Noogan suggested that water in Noogan area was clean water compared to Winebetan and Karondoran. Key word: Types and aquatic insect populations ABSTRAKSerangga akuatik merupakan salah satu organisme yang digunakan dalam menentukan cemaran air. Serangga air ada yang peka dengan adanya limbah yang dibuang pada aliran sungai dan ada pula yang tahan terhadap limbah tersebut. Salah satu serangga yang tahan terhadap limbah adalah Chironomidae. Tujuan penelitian adalah mengetahui jenis serangga akuatik, populasinya dan menghitung indeks keanekaragman serta bitoik indeks. Serangga akuatik pada daerah aliran sungai danau Tondano diperoleh melalui cara tendangan dan Hand Picking. Dari hasil penelitian telah ditemukan 7 ordo, 13 famili dan 16 species. Jumlah serangga akuatik tertinggi ditemukan di Noogan 13 jenis, dan tergolong rendah diperoleh di karondoran 9 jenis. Jenis serangga akuatik yang ditemukan diantaranya, Heptagenia sp, Baetis sp, Caenis sp., Hydropsyhe, dan Chrironomidae. Populasi serangga akuatik yang tertinggi untuk ketiga wilayah terdapat pada Karondoran 38 individu, kemudian diikuti Winebetan 25,5 individu dan Noogan 25,5 individu. Nilai indeks keanekaragaman serangga akuatik yang tertinggi ditemukan Winebetan H i = 2,37, dan terendah Karondoran H i = 2,09. Sebaliknya nilai biotik indeks terendah ditemukan di wilayah Noogan BI= 2,09, kemudian diikuti BI= 2,14 dan tertinggi BI = 2,21. Hal ini menunjukkan bahwa pada wilayah Noogan tergolong air bersih dibandingkan dengan Winebetan dan Karondoran. Kata kunci : Jenis dan populasi serangga akuatikEugenia

Penelitian ini menguji efektivitas kombinasi biolarvasida minyak atsiri serai wangi (Cymbopogon nardus) dengan daun cengkeh (Syzygium aromaticum l.) Terhadap larva nyamuk Ae. aegypti. Penelitian ini bertujuan untuk: (a) menganalisis pengaruh pemberian kombinasi biolarvasida minyak atsiri serai wangi dan daun cengkeh terhadap perkembangan larva Ae. aegypti, (b) menganalisis uji daya bunuh kombinasi biolarvasida serai wangi (sw) dan daun cengkeh (dc) terhadap larva Ae. aegypti, (c) menganalisis uji patogenisitas dari kombinasi biolarvasida serai wangi dan daun cengkeh terhadap larva Ae. aegypti. Uji kombinasi biolarvasida ini dilakukan terhadap larva nyamuk Ae. aegypti instar III  dengan perlakuan variasi kombinasi konsentrasi “SW 2% (P)”, “ SW 0,75% ” + “DC1,25% (P1)”, “SW 1%” + “DC 1% (P2)”, “SW 1,25 %” + “DC 0,75% (P3)” , “DC 2% (P4)”. dan Kontrol air (P-). Themepos (P+). Parameter yang diamati meliputi gejala, persentase mortalitas dan waktu kematian.  Mortalitas larva diamati pada jam ke-6,12,18,24  setelah aplikasi. Perbedaan proporsi mortalitas antar tingkat konsentrasi dengan control diuji dengan metode chi-kuadrat sedangkan lT50 dengan analisis probit.  Hasil penelitian menunjukkan masing-masing kombinasi bahan uji (P,P1,P2,P3 dan P4) tidak memiliki perbedaan pengaruh yang sginifikan sebagai biolarvasida dengan taraf signifikansi sebesar 0,05.. Kesimpulan hasil penelitian ini bahwa kelima konsentrasi bahan uji tersebut tidak memberikan perbedaan pengaruh yang signifikan sebagai biolarvasida. Hal ini menunjukkan bahwa minyak atsiri serai wangi dan daun cengkeh baik diaplikasi secara tunggal maupun dikombinasi memiliki efektifitas larvasida yang sama dengan temephos dalam membunuh larva nyamuk Ae. aegypti. Waktu kematian (LT50)  ekstrak serai wangi 12,72 jam, daun cengkeh 6,71 jam dan kombinasi 6,38 jam.Kata kunci: Biolarvasida; efektifitas; konsentrasi; patogenisitas The Effectiveness of Biolarvacide Essential Oil of Vitronella (Cymbopogon nardus) with Clove Leaves (Syzygium aromaticum.L.) on Ae. aegypti Mosquito Larvae ABSTRACTThis study tested the effectiveness of the biolarvicide combination of citronella essential oil (cymbopogon nardus) and clove leaf (syzygium aromaticum L.) against the larvae of Ae. aegypti. This study aims to: (a) analyze the effect of giving a combination of biolarvicides of citronella essential oil and clove leaves on the development of Ae. aegypti, (b) analyzing the killing power of the combination of citronella (sw) and clove leaf (dc) biolarvicides against Ae. aegypti, (c) analyzing the pathogenicity test of the combination of citronella and clove leaf biolarvicides against the larvae of Ae. Agypti. This biolarvicide combination test was carried out on the larvae of Ae. aegypti instar iii with treatment variations in the concentration combination “SW 2% (P)”, “SW 0.75%” + “DC1.25% (P1)”, “SW 1%” + “DC 1% (P2)”, “SW 1.25%” + “DC 0.75% (P3)” , “DC 2% (P4)”. and Water control (P-). Themepos (P+). Parameters observed included symptoms of mortality percentage and time of death. Larval mortality was observed at 6, 12, 18, 24 hours after application. The difference in the proportion of mortality between concentration levels and control was tested by the chi-square method while the lt50 method was tested by probit analysis. The results showed that each combination of test materials did not have a significant difference in effect as a biolarvicide with a significance level of 0.05. The conclusion of this study was that the five concentrations of the test material did not give a significant difference in effect as a biolarvicide. This indicates that the essential oils of citronella and clove leaves, either applied singly or in combination, have the same larvicidal effectiveness as temephos in killing the larvae of Ae. aegypti. Time of death (lt50) citronella extract 12.72 hours, clove leaf 6.71 hours and the combination 6.38 hours.Keywords: Biolarvicides; effectiveness; concentration; pathogenicity

The research aimed to identify important pests which attack sweet potato in the field. Field and laboratory research were conducted. The field research was carried out in sweet potato cropping areas in Minahasa Regency, North Minahasa regency and Tomohon. The laboratory research was conducted in plant pests and disease laboratory, Faculty of Agriculture Sam Ratulangi University Manado to idedntify the important pest species which were found on sweet potato plants. The duration of the study was four months starting from December 2010 until March 2011. Survey method was applied with purposive random sampling. The research was used 4 period of plant growth namely 1 month, 2 months,3 months, and 4-5 months after planting. The result showed that there were five orders identified, attacking sweet potato since the age of 1-4 months in Minahasa regency, Tomohon and North Minahasa regency. The five orders were Orthoptera, Hemiptera, Homoptera, Lepidoptera, and Coleoptera. The damage on the leaves were caused by pests coreidae, Cicadelidae, Spodoptera sp (Noctuidae), Valanga sp (Acrididae), and Oxya sp. (Acrididae), whereas on the stem was Omphisa sp (Pyralidae). Damage on the tuber was caused by Gryllotalpa sp (Gryllotalpidae), Cylas formicarius (Curculionidae) and Oryctes sp (Dynastidae).

The objectives of this study are: (1) to inventory Trichoderma spp. in North Minahasa District, South Minahasa District, and Tomohon City-Minahasa District, (2) inventory of Trichoderma spp. in the rhizosphere of cultivated and fallow gardens, and (3) calculate the population density of Trichoderma spp. all soil samples. The scope of this study is the biological control of plant pathogens, induce plant resistance, and biological fertilizer production. Trichoderma isolation spp. has been carried out by dilution method and cultured on PDA + antibiotics. Population density of Trichoderma spp. calculated using the plate calculation method. Identification of this species function based on the color and patterns of sporulation in the colony; hyphae and clamydospores; conidiophores; and phialides and phialospores. Trichoderma species found in North Minahasa District were T. harzianum, T. koningii, and T. viride; in South Minahasa District, T. koningii and T. viride; and in Tomohon City-Minahasa District, T. koningii and T. viride. In fallow gardens were T. harzianum, T. koningii, and T. viride, and in cultivated gardens were T. koningii and T. viride. Population densities of Trichoderma sp. in South Minahasa District, North Minahasa District, and Tomohon City-Minahasa District, respectively 1,363.64, 466.67, and 26.67 CFU / g soil.