Judul: Endophytic fungi of wild zingiberaceae from Mount Halimun Salak National Park
Abstrak: The genus Colletotrichum, Diaporthe and Guignardia can live as plant pathogens on a wide variety of tropical woody, herbaceous and graminicoulos plants as well as fungal endophytes of many healthy plants. These two life styles are apparently caused by their biotrophic life strategies as such that they live as symptomless endophytes of living plant tissues. The species in Colletotrichum, Diaporthe and Guignardia have been reported to cause serious diseases in various economic plants in Indonesia. The exploration of these fungal endophytes was mainly done on economic plants. Those from non-cultivated plants in natural habitats are much less studied, with most studies being of endophytic strains. No reports are found on fungal endophyte from wild Zingiberaceae plant, therefore it is necessary to conduct research on the endophytic fungi on Zingiberaceae in order to provide information related fungal endophyte of wild Zingiberaceae in Indonesia. All fungal species recorded from Indonesia were mostly identified based on morphological characters. In this research, isolates of the fungal endophyte was collected by conventional isolation method. The isolates were then identified molecularly based on their ITS1F-ITS4 sequence. These sequences were aligned with MAFFT online. Phylogenetic analyses with all reference strains were performed using MEGA5 to produce the phylogram. The position and bootstrap value for branch support became the criteria of naming the isolates. Eleven isolates of fungal endophytes were obtained from different part of four species of Zingiberaceae at Mount Halimun Salak National Park (MHSNP) namely Alpinia malaccensis, Ammomum gracile, Etlingera punicea and Zingiber odoriferum. These consisted of nine isolates of Colletotrichum spp., one each isolate of Diaporthe infecunda and Guignardia mangiferae. Three of Colletotrichum isolates were belong to gloeosporioides clade, and six others were separate and made its own clade. The Colletotrichum species distributed widely on those four plant species at different plant part, one isolate of Colletotrichum kahawae subsp. kahawae from root of Etlingera punicea, one isolate of Colletotrichum aff. siamense from root of Alpinia malaccensis, and seven isolates of unidentified Colletotrichum species either from root of Alpinia malaccensis, pseudostem and leaf of Ammomum gracile, and from root of Zingiber odoriferum. One isolate of Diaporthe infecunda was from pseudostem of Alpinia malaccensis and one isolate Guignardia mangiferae was from pseudostem of Zingiber odoriferum. All of this finding is new records on fungal endophytes from wild species of Zingiberaceae and may contribute to the management of domestication of these plants.
Keyword: endophyte, ITS, Zingiberaceae

Judul: Dampak Domestikasi Zingiberaceae di Taman Nasional Gunung Halimun Salak Terhadap Keragaman Cendawan Endofitnya
Abstrak: Taman Nasional Gunung Halimun Salak (TNGHS) merupakan salah satu hutan tropis yang tersisa di Pulau Jawa. TNGHS memiliki keragaman Zingiberaceae liar yang relatif tinggi. Dua spesies diantaranya yakni Alpinia malaccensis (AM) dan Horstendia conica (HC), telah didomestikasi sebagai tanaman pekarangan di sekitar area hutan sebagai tanaman obat. Dampak domestikasi tanaman terhadap cendawan patogen sering dilaporkan, namun dampak domestikasi tanaman terhadap cendawan endofit jarang diteliti. Oleh sebab itu penelitian ini bertujuan untuk menganalisis dampak dari domestikasi Zingiberaceae di TNGHS terhadap keragaman cendawan endofit yang berasosiasi dengan dua spesies Zingiberaceae tersebut. Keragaman cendawan endofit asal Zingiberaceae liar dan domestikasi dianalisis berdasarkan cendawan yang dapat dikulturkan. Masing-masing satu individu tanaman diambil dari rumpun AM dan HC liar serta rumpun AM dan HC domestikasi terpilih. Setiap tanaman terdiri atas akar, rimpang, batang dan daun. Semua bagian tanaman disterilisasi permukaan. Potongan-potongan setiap bagian tanaman ditanam pada media MEA (Malt Extract Agar) half strength dan diinkubasi pada suhu kamar. Cendawan yang tumbuh dari bagian-bagian tanaman tersebut diisolasi dan dimurnikan. Identifikasi hingga ke tingkat spesies dilakukan dengan pendekatan morfologi serta molekuler berdasarkan sekuen ITS rDNAnya. Secara morfologi, koleksi biakan cendawan endofit ini dapat dibagi ke dalam 17 morfotipe. Setelah diidentifikasi secara molekuler morfotipe ini terdiri atas 19 spesies cendawan yaitu Arthrinium malaysianum, Aspergillus flavipes, As. sydowii, Chaetomium globosum, Cladosporium sp., Cl. oxysporum, Colletotrichum aff. boninense-complex, Co. aff. cliviae-complex, Co. aff. gloeosporioides-complex, Diaporthe sp., D. anacardii, D. gardenia, Exophiala sp., E. lecanii-corni, Guignardia mangiferae, Ochroconis gallopava, Penicillium citrinum, Pyricularia costina, dan Sydowiellaceae tidak bersporulasi. Semua cendawan endofit pada Zingiberaceae tergolong Ascomycota, Pezizomycotina yang tersebar ke dalam 3 kelas yaitu: Dothideomycetes, Eurotiomycetes, dan Sordariomycetes. Domestikasi berpengaruh pada keragaman dan keberadaan cendawan endofit. Keragaman cendawan endofit pada inang domestikasi relatif rendah dibandingkan dengan inang liarnya, namun berbanding terbalik dengan populasi cendawan endofitnya. Zingiberaceae ditanam di daerah yang lebih terbuka dibandingkan dengan Zingiberaceae liar yang hidup di bawah kanopi hutan yang menyebabkan lingkungannya lebih teduh dengan kelembapan yang relatif lebih tinggi. Beberapa cendawan endofit menunjukkan pereferensi terhadap lingkungannya. Komposisi komunitas cendawan endofit bervariasi bergantung spesies inangnya. Selain itu, distribusi spesies cendawan endofit juga bervariasi bergantung habitat mikronya. Secara umum, spesies cendawan endofit lebih banyak ditemukan pada mikro-habitat tertentu. Daun merupakan mikro-habitat yang paling disukai cendawan endofit diikuti dengan akar, batang dan rimpang. iv iii Domestikasi Zingiberaceae mendorong hilangnya spesies cendawan endofit dari inang liarnya atau sebaliknya mendorong munculnya spesies cendawan endofit yang baru ditemukan pada inang yang dibudidayakan. Aspergillus flavipes, As. sydowii, Cl. oxysporum, Diaporthe sp. dan Py. costina ditemukan pada inang liarnya dan tidak ditemukan lagi pada inang domestikasi. Arthrinium malaysianum, Ch. globosum, Co. aff. cliviae-complex, D. gardenia, dan Sydowiellaceae tak bersporulasi hanya ditemukan pada inang domestikasi. Sementara itu, beberapa spesies endofit yaitu Co. aff. boninense-complex, Cladosporium sp., Co. aff. gloeosporioides-complex, dan E. lecanii-corni, tampaknya tidak dipengaruhi oleh domestikasi. Penelitian ini mengindikasikan adanya dampak domestikasi Zingiberaceae terhadap keragaman dan keberadaan cendawan endofitnya. Keterbatasan dalam jumlah dan frekuensi pengambilan contoh serta pemilihan metode isolasi menyebabkan hasil penelitian ini hanya dapat menjadi informasi awal mengenai dampak domestikasi terhadap keragaman endofit terutama pada Zingibercaeae. Oleh sebab itu penelitian ini masih perlu diperkuat dengan penambahan jumlah
Keyword: Domestikasi, cendawan endofit, keragaman, Zingiberaceae

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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