Oil palm is a very important plant because it is one of the world's vegetable oil producing plants. Oryctes rhinoceros is one of the important pests that attack oil palm plants. The recommended control of Oryctes rhinoceros is used integrate pest control, one of which can use the biological agent of the fungus Metarhizium anisopliae. The composition of oil palm empty fruit bunches can be a medium rich in organic matter for the breeding of Fungus Metarhizium anisopliae. This research aims to study the best concentration of Metarhizium anisopliae in oil palm empty fruit bunch compost (metankos) to infect Oryctes rhinoceros larvae. This research was conducted in Laboratory of Plant Pests, Faculty of Agriculture, University of Riau, from April to October 2019. This study is experimental with Complete Randomized Design with 6 treatments and 5 replications. The treatment of Metarhizium anisopliae concentration on metankos consisted of : 0 g.l−1, 10 g.l−1, 20 g.l−1, 30 g.l−1, 40 g.l−1, and 50 g.l−1 Metarhizium anisopliae. The results show is concentration of Metarhizium anisopliae 50 g.l−1 water with a total mortality of 56% larvae.

Penelitian bertujuan untuk mempelajari pengaruh interaksi pemberian Trichokompos tandan kosong kelapa sawit (TKKS) terformulasi dan pupuk kalium, pengaruh utama keduanya terhadap pertumbuhan dan produksi bawang merah (Allium ascalonicum L.) di lahan gambut. Penelitian dilakukan secara eksperimen dalam bentuk faktorial 4 x 3 disusun menggunakan Rancangan Acak Lengkap (RAL). Trichokompos TKKS terformulasi sebagai faktor I terdiri dari 4 taraf (15, 20, 25 dan 30 ton/ha) dan pupuk kalium sebagai faktor II terdiri dari 3 taraf (50, 100 dan 150 kg K₂O/ha). Parameter yang diamati antara lain tinggi tanaman, jumlah umbi berdasarkan kriteria diameter dan bobot segar umbi per rumpun sampel. Hasil penelitian menunjukkan bahwa pemberian 25 ton/ha Trichokompos TKKS terformulasi dan 100 kg K₂O/ha mengurangi umbi diameter kecil sebesar 3 kali (228,6%), sebaliknya meningkatkan umbi diameter besar sebesar 24 kali (2324,2%) dan bobot segar umbi per rumpun sampel sebesar 1,7 kali (71,3%) dibandingkan pemberian 15 ton/ha pada dosis pupuk kalium yang sama (100 kg K₂O/ha). Peningkatan dosis Trichokompos TKKS terformulasi dari 15 ke 25 ton/ha mengurangi umbi diameter kecil, sebaliknya meningkatkan umbi diameter besar dan bobot segar umbi per rumpun sampel. Peningkatan dosis ke 30 ton/ha masih berpengaruh terhadap peningkatan parameter tersebut kecuali jumlah umbi diameter kecil dan jumlah umbi diameter besar. Peningkatan dosis pupuk kalium dari 50 ke 100 hingga 150 kg K₂O/ha tidak mempengaruhi seluruh parameter yang diamati.

The addition of ameliorant Fe3+ and rock phosphates containing high Fe cation can reduce effect of toxic organic acids, increase peat stability through formation of complex compounds and reduce carbon emission. The research was conducted in the laboratory and green house of the Departement of Soil Science, Faculty of Agriculture, Bogor Agriculture University. Peat samples with hemic degree of decomposition were taken from Riau. Rock phosphates were taken from the rock phosphates of PT. Petrokimia Gresik, Christmas Island phosphates, and Huinan China and FeCl3.6H2O was used as the other Fe3+ source.  The aims of the research were to study (a) the effect of the applications of ameliorant Fe3+ and rock phosphates on the P content of plants dan (b) the effect of the application ameliorant Fe3+ and the contribution of Fe cation in rock phosphates in the decrease of carbon emission. The results showed that the P content of plants rice increased 58 – 286 % with the applications of ameliorant Fe3+ and rock phosphates. The estimation of carbon loss through CO2 and CH4 emissions from peats if planted continuously with rice was around 2.5, 2.2 and 2.6   Mg of C ha-1 year-1 respectively in field capacity condition, two times of field capacity condition, and 5 cm of saturated condition.  The application of ameliorant Fe3+ and rock phosphates containing high Fe cation increased the stability of peats and reduced the carbon loss around  1.7 Mg of C ha-1 year-1 (64%) in 5 cm of saturated condition, 1,3 Mg of C ha-1 year-1 (58%) in two times of field capacity condition, and 1.0 Mg of C ha-1 year-1 (41%) in field capacity condition.

Penelitian bertujuan untuk mendapatkan dosis pupuk P pada lahan sawah Balai Benih Induk (BBI) Pekanbaru Propinsi Riau untuk pertumbuhan dan hasil produksi padi yang optimal. Penelitian menggunakan Rancangan Acak Lengkap dengan 5 perlakuan yang terdiri dari 5 taraf (46; 57,5; 69; 80,5; 92 kg P2O5/ha), masing-masing perlakuan diulang 4 kali, dosis yang digunakan BBI adalah 69 kg P2O5/ha. Parameter yang diamati tinggi tanaman, jumlah anakan produktif, jumlah gabah per malai, bobot gabah bernas per sampel, bobot gabah bernas per meter persegi, bobot 1000 butir gabah dan indeks panen, serta pH, P tersedia dan P potensial tanah. Data hasil pengamatan tiap parameter dianalisis secara statistik menggunakan analisis ragam dan uji lanjut dengan DNMRT taraf 5%.Hasil penelitian menunjukan bahwa penurunan dosis P dari 69 kg P2O5/ha (dosis BBI) ke 46 kg P2O5/ha menghasilkan tinggi tanaman, jumlah anakan produktif, jumlah gabah per malai, bobot gabah bernas per sampel, bobot gabah bernas per meter persegi dan indeks panen lebih tinggi dibadingkan pemberian P pada dosis BBI (69 kg P2O5/ha) dan di bawah maupun di atasnya (57,5, dan 80,5, 92 kg P2O5/ha). Pemberian dosis 57,5 kg P2O5/ha terhadap bobot 1000 butir gabah menghasilkan perbedaan yang nyata dari dosis 69 kg P2O5/ha (dosis BBI).