Judul: Vegetative Characteristic Evaluation of Tip Cuttings on Various Genotypes of Marigold (Tagetes erecta L.)
Abstrak: Tanaman hias marigold (Tagetes erecta L.) merupakan salah satu tanaman hias yang banyak dibudidayakan di Indonesia karena memiliki beragam manfaat. Pada tanaman marigold diketahui terdapat mutan steril jantan yang memiliki bunga dominan ray flower sehingga sulit untuk didapatkan biji yang fertil. Penelitian oleh tim peneliti IPB telah menghasilkan beberapa genotipe yang memiliki bunga dominan ray flower sehingga perbanyakan secara vegetatif perlu dipelajari. Penelitian ini bertujuan untuk mengevaluasi karakter vegetatif beberapa genotipe tanaman marigold hasil rakitan peneliti IPB untuk mendapatkan genotipe yang potensial untuk diperbanyak melalui stek pucuk. Penelitian dilaksanakan di Green House Kebun Percobaan Leuwikopo IPB pada bulan April – Agustus 2021. Rancangan yang digunakan pada penelitian ini adalah Rancangan Kelompok Lengkap Teracak (RKLT) faktor tunggal dengan 38 genotipe uji serta uji lanjut Tukey pada taraf a 5%. Berdasarkan hasil penelitian, beberapa genotipe menujukkan respon yang baik terhadap perlakuan induksi akar menggunakan NAA dan Vitamin B1 (thiamin). Analisis ragam yang dilakukan pada karakter pengamatan tinggi tanaman, diameter batang dan jumlah cabang memberikan nilai F value yang lebih besar dibanding F tabel sehingga dapat disimpulkan bahwa genotipe berpengaruh nyata pada ketiga karakter vegetatif yang diamati. Pada pengamatan tinggi tanaman, genotipe PM MV3 0.5 C 21.2.11, 8 S2, dan X MV3 40.36.37.1 memberikan hasil yang berbeda nyata. Pada pengamatan diameter batang, terdapat 16 genotipe yang memberikan hasil berbeda nyata yaitu genotipe PM MV3 0.5 C 21.1.12, PM MV3 0.5 C 21.2.11, PM MV3 20.23.2.21, 5 S2, V MV3 30, 13 S2, PM S MV3 0.5 C, MR MV2 50.13.4, 12 S2, V MV3 30.3.37, 10 S2, PM MV3 40.5.2.2, MR MV3 30.6.2.8, 9 S2, 8 S2, dan X MV3 40.36.37.1. Pada karakter jumlah cabang, genotipe PM MV3 0.5 C 21.1.12 dan X MV3 40.36.37.1 memberikan hasil yang berbeda nyata., The ornamental plant, marigold (Tagetes erecta L.), is one of the widely cultivated ornamental plants in Indonesia due to its various benefits. In marigold plants, it is known that there are male sterile mutants with dominant ray flowers, making it difficult to obtain fertile seeds. Research conducted by the IPB research team has produced several genotypes with dominant ray flowers, thus vegetative propagation needs to be studied. This study aims to evaluate the vegetative characteristics of several genotypes of marigold plants resulting from IPB researchers' breeding to identify genotypes with potential for propagation through stem cuttings. The research was conducted at the Green House of Kebun Percobaan IPB Leuwikopo from April to August 2021. The design used in this study was a Completely Randomized Design (CRD) with a single factor with 38 test genotypes and Tukey's advanced test at a 5% level. Based on the research results, several genotypes showed good responses to root induction treatments using NAA and Vitamin B1 (thiamine). Analysis of variance performed on plant height, stem diameter, and number of branches provided F values greater than the F table, indicating that genotypes significantly influenced the three observed vegetative characters. In plant height observation, genotypes PM MV3 0.5 C 21.2.11, 8 S2, and X MV3 40.36.37.1 showed significantly different results. In stem diameter observation, there were 16 genotypes that showed significantly different
Keyword: marigold, karakter vegetatif, induksi akar, ray flower

Judul: Growth and Flowering Response of Two Clones of Marigold (Tagetes erecta L.) to Frequency of Pinching and Fertilization
Abstrak: Marigold (Tagetes erecta L.) merupakan tanaman herba hias yang berasal dari famili Asteraceae. Bunga marigold memiliki bentuk yang unik serta warna yang indah sehingga biasa digunakan sebagai tanaman hias dalam pot maupun sebagai karangan bunga. Marigold memiliki potensi untuk dikembangkan karena memiliki nilai ekonomis yang tinggi dan bunganya memiliki banyak kegunaan. Salah satu tindakan budidaya yang dapat meningkatkan pertumbuhan dan kualitas bunga adalah dengan perlakuan pinching dan pemupukan. Penelitian dilaksanakan pada bulan Desember 2022 - Juni 2023 di Kebun Percobaan CV. Benih Dramaga, Kecamatan Dramaga, Kabupaten Bogor. Penelitian ini menggunakan Rancangan Kelompok Lengkap Teracak (RKLT) faktorial dengan taraf dua faktor yaitu frekuensi pinching dan frekuensi pemupukan AB mix. Faktor pertama adalah frekuensi pinching dari tiga taraf yaitu: 1 hari sekali (A1), 2 hari sekali (A2), dan 3 hari sekali (A3). Faktor kedua adalah frekuensi pemupukan dari dua taraf yaitu 2x/minggu (B1) dan 3x/minggu (B2). Pupuk yang digunakan pada penelitian ini adalah pupuk AB mix. Varietas marigold yang digunakan yaitu Sudamala Emas 1 sebagai tanaman utama dan Maharani sebagai tanaman pembanding. Hasil penelitian dari pengaruh frekuensi pinching, frekuensi pemupukan serta interaksi pinching dan pemupukan menunjukan pengaruh yang tidak berbeda nyata terhadap tinggi tanaman, jumlah bunga per tanaman, bobot bunga per tanaman, bobot bunga per kuntum, diameter bunga, dan Umur 50% berbunga., Marigold (Tagetes erecta L.) is an ornamental herbaceous plant from the Asteraceae family. Marigold flowers have a unique shape and beautiful colors so they are usually used as ornamental plants in pots or as flower bouquets. Marigolds have the potential to be developed because they have high economic value and the flowers have many uses. One of the cultivation measures that can improve the growth and quality of flowers is pinching and fertilizing. The research was carried out in December 2022 - June 2023 at the CV. Benih Dramaga, Perumahan IPB Alam Sinarsari Dramaga, Kecamatan Dramaga, and Kabupaten Bogor. This research used a factorial Randomized Complete Block Design (RCBD) with two factor levels, namely pinching frequency and AB mix fertilization frequency. The first factor was the frequency of pinching from three levels, namely: once a day (A1), once every 2 days (A2), and once every 3 days (A3). The second factor was the frequency of fertilization at two levels, namely 2x/week (B1) and 3x/week (B2). The fertilizer used in this research was AB mix fertilizer. The marigold variety used was Sudamala Emas 1 as the main variety and Maharani as the comparison. The results of the study of the effect of pinching frequency, fertilization frequency and the interaction of pinching and fertilization showed an effect that was not significantly different from plant height, number of flowers per plant, flower weight per plant, flower weight per flower, flower diameter, and 50% flowering time.
Keyword: marigold, pinching, pemupukan

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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