Judul: Studi Pustaka Potensi Marigold (Tagetes spp.) dalam Mengendalikan Meloidogyne spp. yang Ramah Lingkungan
Abstrak: Meloidogyne spp. atau nematoda puru akar merupakan nematoda endoparasit penting di dunia yang sering ditemukan menyerang dan menjadi masalah pada beberapa tanaman karena memiliki distribusi persebaran dan inang yang luas. Kehilangan hasil akibat Meloidogyne spp. pada beberapa komoditas sudah banyak dilaporkan. Pengendalian secara kimiawi untuk mengendalikan nematoda dapat menyebabkan berbagai efek negatif bagi lingkungan maupun organisme lain sehingga diperlukan alternatif pengendalian yang ramah lingkungan. Tanaman Marigold (Tagetes spp.) merupakan tanaman hias yang diketahui sering digunakan sebagai tanaman antagonis yang bermanfaat untuk mengendalikan hama dan penyakit. Ekstrak dari tanaman Tagetes spp. serta agens hayati yang berasal dari tanaman tersebut juga diketahui dapat menekan serangan nematoda Meloidogyne spp. Penelitian ini bersifat studi pustaka yang bertujuan mengumpulkan dan memberikan informasi lebih dalam mengenai tanaman marigold, mengevaluasi potensi tanaman marigold, serta mengetahui beberapa teknik pengendalian nematoda puru akar (Meloidogyne spp.) dengan memanfaatkan tanaman marigold (Tagetes spp.). Data diperoleh dari berbagai sumber referensi skripsi, tesis, jurnal, buku, atau artikel ilmiah yang relevan dengan topik yang diambil melalui situs atau sumber-sumber pencarian yang sudah terverifikasi, kemudian dianalisis dengan menggunakan metode analisis deskriptif. Hasil penelitian menunjukkan bahwa marigold (Tagetes spp.) dapat menekan jumlah puru 24%-98% dan jumlah populasi nematoda 15%-100%, sehingga berpotensi sebagai alternatif pengendalian nematoda Meloidogyne spp. utamanya sebagai pengganti nematisida sintetis. Beberapa teknik pengendalian yang dapat dilakukan diantaranya rotasi tanam, cover crop, intercropping, ekstrak nabati marigold, serta pemanfaatan agens hayati yang berasal dari tanaman marigold. Informasi yang terkumpul mengenai teknik pengendalian dapat dijadikan acuan dalam mengendalikan nematoda puru akar (Meloidogyne spp.) Kata kunci: nematoda puru akar, PHT, Tagetes sp., ramah lingungan, tanaman antagonis, Meloidogyne spp. also known as root-knot nematode is an important endoparasitic nematode in the world that is often found attacking and causing problems in several plants because its wide distribution and host. Crop loss due to Meloidogyne spp. have been widely reported. Chemical control to controlling Meloidogyne spp. is causing various negative effect on environment and other organisms, so that alternative control is needed. Marigold (Tagetes spp.) is an ornamental plants that is known to be used as an antagonistic plant which is useful as an alternative for controlling pests and diseases. Extract from Tagetes spp., biological agents and materials from these plants are also known to control Meloidogyne spp. This research is a literature study to collect and provide more information about marigold (Tagetes spp.), potency of marigold (Tagetes spp.), and to know the friendly environment technique to control root-knot nematode (Meloidogyne spp.). Data was obtained by collecting from many references, journals, books, or scientific articles that are relevant to the topic taken through sites or verified search sources. The result showed that marigolds can reduce the number of gall 24%-98% and nematode population 15%-100%, so it has the potential as an alternative to control nematode as a substitute for synthetic nematicides. Some of the techniques that can be use include plant rotation, cover crop, intercropping, marigold extract, and biological agents. The information gathered can be used as an reference to alternative control Meloidogyne spp. Keywords: environmentally friendly, IPM, root-knot nematode, plant antagonist, Tagetes sp.
Keyword: environmentally friendly, IPM, root-knot nematode, plant antagonist, Tagetes sp.

Judul: Studi Pustaka Inventarisasi Nematoda Puru Akar (Meloidogyne spp.) pada Beberapa Spesies Gulma
Abstrak: Salah satu penyebab menurunnya produk hasil pertanian diatas adalah serangan organisme pengganggu tanaman (OPT). Gulma dan nematoda parasit tanaman seperti Meloidogyne spp. dianggap sebagai salah satu organisme pengganggu tanaman (OPT) yang dapat menghambat pertumbuhan, perkembangan, dan produktivitas tanaman budi daya. Salah satu tindakan preventif yang dapat dilakukan untuk mencegah kerusakan yang lebih besar adalah dilakukannya tindakan pengendalian. Diketahui beberapa jenis gulma juga dapat bertindak sebagai inang alternatif bagi patogen penyebab penyakit tanaman, salah satunya adalah nematoda parasit. Penelitian ini bertujuan untuk melakukan inventarisasi nematoda parasit tanaman Meloidogyne spp. yang berasosiasi dengan beberapa jenis spesies gulma. Data dalam penelitian ini diperoleh berdasarkan data sekunder berbasis pada studi pustaka. Metode ini memanfaatkan data sekunder untuk dijadikan sumber data utama dengan menggunakan teknik uji statistik yang sesuai untuk mendapatkan informasi untuk kemudian diolah secara sistematis. Hasil penelitian menunjukkan bahwa gulma yang terinfeksi M. incognita berjumlah 32 famili dengan 115 spesies, M. javanica 14 famili 97 spesies, M. arenaria 12 famili dengan 43 spesies, dan M. hapla 11 famili dengan 29 spesies. Meloidogyne spp. ditemukan paling banyak menyerang jenis gulma berdaun lebar dibandingkan gulma rumput dan teki-tekian., One of the causes of the decline in agricultural products is attack of plant pests and desease. Weeds and plant parasitic nematodas such as Meloidogyne spp. are considered as plant pest that can inhibit the growth, development and productivity of cultivated plants. One of the preventive measures that can be taken to prevent greater damage is to carry out control measures. It is known that several types of weeds can also act as alternative hosts for pathogens that cause plant diseases, one of which is parasitic nematodas. The objective of this research was to carry out an inventory of root knot nematoda Meloidogyne spp. which is associated with several types of weed spesies. The data ini this research was obtained based on secondary data based on literature study. This method utilize secondary data as the main data source by using appropriate statistical test techniques result showed that 32 families of weeds included 115 spesies are infected with M. incognita, M. javanica was found in 14 families with 97 spesies of weeds, M. arenaria was found to attack 12 families with 43 spesies of weeds, and M. hapla attacked 11 families with 29 weed spesies. Meloidogyne spp. most commonly found to attack broadleaf weeds compared to glass and sedge weeds.
Keyword: meloidogyne spp., gulma, inang alternatif

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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