Judul: Study of Anthracnose Disease Management (Colletotrichum spp.) of Fruits by Plant Extracts
Abstrak: Buah merupakan salah satu produk hortikultura yang banyak diminati oleh masyarakat karena kaya akan nutrisi yang bermanfaat bagi kesehatan tubuh. Namun, buah pascapanen saat ini masih memiliki banyak masalah, seperti penyakit antraknosa (Colletotrichum spp.). Ekstrak tanaman merupakan senyawa alami yang sangat menjanjikan untuk digunakan sebagai alternatif fungisida sintetis karena memiliki aktivitas antimikroba yang aman bagi kesehatan manusia dan kelestarian lingkungan. Studi pustaka ini bertujuan mencatat dan menganalisis tren penelitian tentang aplikasi ekstrak tanaman dalam mengendalikan penyakit antraknosa (Colletotrichum spp.) pada buah-buahan. Studi literatur dilakukan dengan mengumpulkan berbagai data dan informasi dari beberapa literatur yang bereputasi. Data yang diperoleh dari masing-masing literatur, termasuk uji in vitro dan in vivo dari masing-masing ekstrak tanaman kemudian dirangkum dan ditabulasikan. Tahapan penulisan dimulai dari perumusan masalah, pengumpulan data, analisis dan sintesis data, kesimpulan dan saran. Hasil studi literatur menunjukkan bahwa ekstrak yang paling efektif dalam menekan pertumbuhan pada pengujian in vitro, yaitu ekstrak daun sirih (Piper aduncum), daun sambiloto (Andrographis paniculata), daun gambir (Uncaria gambir), dan daun karuk (Piper sarmentosum) dengan daya hambat 100%. Ekstrak daun serai wangi (Cymbopogon nardus), daun karuk (Piper sarmentosum), daun mint (Mentha cordifolia), rimpang jahe (Zingiber officinale), dan daun melati laut (Clerodendrum inerme) mampu menghambat perkecambahan konidia hingga 100%. . Ekstrak tanaman yang efektif pada uji in vivo, yaitu rimpang jahe (Zingiber officinale) dan ekstrak daun kersen muda (Muntingia calabura) dengan kejadian dan keparahan penyakit sebesar 18% dan 1,55%., Fruits are one of the horticultural products that are in great demand by the public because they are rich in nutrients that are beneficial to the health of the body. However, postharvest fruits currently still has many problems, such as anthracnose disease (Colletotrichum spp.). Plant extracts are natural compounds that are very promising to be used as an alternative to synthetic fungicides because they have an antimicrobial activity that is safe for human health and environmentally friendly. This literature study aims to record and analyze trends in research about application of plant extracts to control anthracnose disease (Colletotrichum spp.) of fruits. The literature study was carried out by collecting various data and information from several reputable literature. The data obtained from each literature, including in vitro and in vivo test of each plant extract were then summarized and tabulated. The writing stages start from problem formulation, data collection, data analysis and synthesis, conclusions and suggestions. The literature study results indicate that extracts that were most effective in suppressing growth in vitro testing were: extract of Betel leaves (Piper aduncum), Sambiloto leaves (Andrographis paniculata), Gambier leaves (Uncaria gambir), and Karuk leaves (Piper sarmentosum) with 100% hyphal growth inhibition. Extracts of Citronella leaves (Cymbopogon nardus), Karuk leaves (Piper sarmentosum), Mint leaves (Mentha cordifolia), Ginger rhizome (Zingiber officinale) and Sea jasmine leaves (Clerodendrum inerme) were most effective to inhibit conidial germination until 100%. The effective plant extracts in in vivo test namely Ginger rhizome (Zingiber officinale) and Young cherry leaf extract (Muntingia calabura) with disease incidence and severity of 18% and 1,55%, respectively.
Keyword: Piper sarmentosum, postharvest management, Zingiber officinale

Judul: Mycobiota on chilli fruits: their effect on colletotrichum capsici, causing anthracnose
Abstrak: Colletotrichum capsici merupakan cendawan patogen penyebab antraknosa pada berbagai buah tropis, terutama pada buah cabai. Penggunaan agens kontrol biologi merupakan alternatif pengendalian penyakit pascapanen pada produk hortikultura. Penelitian ini bertujuan untuk menguji potensi antagonistik mikobiota pada buah cabai terhadap C. capsici. Cendawan patogen dan cendawan uji diisolasi dari buah cabai merah besar var. Imperial-308 dan Hibrida F1 Maraton yang diperoleh dari 3 pasar tradisional di Kotamadya Bogor. Isolasi C. capsici menghasilkan 4 isolat. Colletotrichum capsici CPB I.1 memiliki patogenisitas tertinggi pada buah cabai merah besar var. IPB Perbani. Isolasi cendawan uji dilakukan dengan menggunakan metode pengenceran serial yang dilanjutkan dengan metode cawan tuang menghasilkan 14 isolat, terdiri atas 7 isolat cendawan berfilamen dan 7 isolat khamir. Uji antagonisme dilakukan dengan menggunakan metode oposisi langsung pada media Potato Dextrose Agar (PDA) menghasilkan 4 isolat cendawan antagonis yang menyebabkan persentase hambatan pertumbuhan lebih dari 70% terhadap C. capsici CPB I.1, yaitu 3 isolat cendawan berfilamen (Plectosphaerella cucumerina, isolat MF 2, dan Aspergillus flavus) dan 1 isolat khamir (Issatchenkia orientalis). Dua cendawan antagonis (P. cucumerina dan I. orientalis) tidak menyebabkan penyakit pada buah cabai var. IPB Perbani, sehingga berpotensi sebagai agens kontrol biologi., Colletotrichum capsici is a pathogenic fungus causing anthracnose on various tropical fruits, especially chilli fruit. Biological control agents have been used as an alternative to control postharvest diseases. This study aims to examine the antagonistic potential of mycobiota on chilli fruit against C. capsici. Pathogenic fungus and test fungi were isolated from red chilli fruits var. Imperial- 308 and Hibrida F1 Maraton collected from 3 traditional markets in Municipality of Bogor. Four isolates of C. capsici were obtained from red chilli fruits infected by anthracnose. Colletotrichum capsici CPB I.1 showed the highest pathogenicity on red chilli fruits var. IPB Perbani. Fourteen isolates of test fungi were obtained from healthy red chilli fruits using serial dilution method, followed by pour plate method. They consisted of 7 filamentous fungi and 7 yeast isolates. Test of antagonism using direct opposition method on PDA obtained 4 antagonist fungal isolates which inhibited the growth of C. capsici CPB I.1 more than 70%. They consisted of 3 filamentous fungi (Plectosphaerella cucumerina, isolate MF 2, and Aspergillus flavus) and 1 yeast (Issatchenkia orientalis). Two isolates of antagonist fungi (P. cucumerina and I. orientalis) did not cause any diseases of chilli fruits var. IPB Perbani, consequently they can be used as biocontrol agents. Keywords: anthracnose, chilli fruit, Colletotrichum capsici, mycobiota
Keyword: antraknosa, buah cabai, Colletotrichum capsici, mikobiota

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.
Keyword: