Judul: Effect of Paclobutrazol and Encapsulated Nitrogen
Fertilizer on Growth and Yield of Marigold (Tagetes erecta L.)
Abstrak: RADHITA SALSABILA. Pengaruh Pemberian Paclobutrazol dan Pupuk Nitrogen Terenkapsulasi pada Pertumbuhan dan Hasil Marigold (Tagetes erecta L.). Dibimbing oleh EDI SANTOSA dan KRISANTINI. Marigold merupakan florikultura yang memiliki keragaman manfaat. Keragaman manfaat tersebut membuat permintaan terhadap marigold semakin meningkat. Karakteristik batang marigold yang tinggi dan memiliki banyak percabangan membuat marigold tidak proporsional dan rentan rebah. Oleh karena itu, permintaan terhadap marigold belum tercukupi. Penelitian ini bertujuan mengetahui efektivitas paclobutrazol dan nitrogen setelah enkapsulasi dengan natrium alginate terhadap pertumbuhan dan produksi bunga marigold (Tagetes erecta L.). Percobaan dilaksanakan pada bulan November 2023 hingga Januari 2024 di screen house Kebun Percobaan Leuwikopo Institut Pertanian Bogor. Penelitian ini menggunakan rancangan kelompok lengkap teracak dengan 2 percobaan, masing-masing percobaan terdapat 4 perlakuan dan 5 ulangan. Percobaan pertama yaitu enkapsulasi paclobutrazol dengan perlakuan PBZ +/- enkapsulasi dan kontrol +/- enkapsulasi. Percobaan kedua yaitu enkapsulasi pupuk nitrogen dengan perlakuan N +/- enkapsulasi dan kontrol +/- enkapsulasi. Enkapsulasi paclobutrazol nyata membuat tinggi tanaman 2 MST paling rendah dari perlakuan lain, memperpendek panjang ruas 3 MST, memperbesar diameter batang, meningkatan jumlah cabang, meningkatkan bobot bunga, panjang tangkai bunga, panjang akar, dan bobot akar. Enkapsulasi pupuk nitrogen nyata meningkatkan bobot bunga, diameter bunga mekar, dan bobot kering akar. Enkapsulasi pupuk nitrogen tidak berpengaruh terhadap fase vegetatif dan generatif marigold. Kata kunci: komponen hasil, urea, vegetatif, zat pengatur tumbuh, RADHITA SALSABILA. Effect of Paclobutrazol and Encapsulated Nitrogen Fertilizer on Growth and Yield of Marigold (Tagetes erecta L.). Supervised by EDI SANTOSA dan KRISANTINI. Marigold is a floriculture that has a variety of benefits. This diversity of benefits makes the demand for marigolds increase. The characteristics of marigold stems which are tall and have many branches make marigold disproportionate and prone to falling over. Therefore, the demand for marigolds is not yet sufficient. This research aimed to determine the effectiveness of paclobutrazol and nitrogen after encapsulation with sodium alginate on the growth and production of mariold flowers (Tagetes erecta L.). The experiment was carried out from November 2023 to January 2024 at the screen house of the Leuwikopo Experimental Farm, Bogor Agricultural University. This study used a completely randomized design with 2 experiments, each experiment containing 4 treatments and 5 replications. The first experiment was paclobutrazol encapsulation with paclobutrazol treatment +/- encapsulation and control +/- encapsulation. The second experiment was N encapsulation with treatment N +/- encapsulation and control +/- encapsulation. Paclobutrazol encapsulation actually made the plant heigh at 2 WAT the lowest compared to other treatments, shortens internode length at 3 WAT, increases stem diameter, increases number of branches, increases flower weight, flower stalk length, root length and root weight. N encapsulation significantly increased flower weight, bloom diameter, and root dry weight. N encapsulation had no effect on the duration of vegetative and generative phases of marigold. Keyword: growth regulator, urea, vegetative, yield components
Keyword: urea, komponen hasil, vegetatif, zat pengatur tumbuh, growth regulator, vegetative, yield components

Judul: Growth and Flower Yield of African Marigold (Tagetes erecta L.) under Different Pinching Frequencies and Fertilizer Types
Abstrak: Penelitian terkait pengaruh frekuensi pinching (setiap 2, 4 dan 6 hari) serta jenis pupuk (AB Mix dan NPK + Gandasil) terhadap pertumbuhan dan produksi marigold dilakukan di Kebun Percobaan CV. Benih Dramaga pada bulan Maret Juli 2023. Sebanyak tiga percobaan dilakukan secara terpisah berdasarkan bahan tanam, yaitu stek var. Sudamala Oranye 1 serta stek dan benih var. Maharani F1. Percobaan menggunakan stek dilakukan dengan Rancangan Kelompok Lengkap Teracak (RKLT) faktorial dua faktor yaitu frekuensi pinching serta jenis pupuk, benih dilakukan menggunakan RKLT dengan faktor jenis pupuk. Hasil penelitian menunjukkan bahwa frekuensi pinching berpengaruh nyata terhadap persentase tanaman berbunga, diameter serta bobot kuntum Sudamala Oranye 1. Jenis pupuk berpengaruh nyata terhadap persentase tanaman berbunga, warna daun dan mahkota bunga kedua varietas, persentase tanaman terserang layu bakteri Sudamala Oranye 1, serta jumlah tunas per minggu, total cabang baru, bobot segar bunga per tanaman, dan produktivitas Maharani F1 dari benih. Interaksi ditemukan pada jumlah tunas 5 dan 6 MST, total tunas baru per tanaman, dan diameter kuntum Sudamala Oranye 1. Pada kedua varietas, pinching 2 hari sekali menghasilkan komponen hasil tertinggi walaupun tidak berbeda nyata dengan frekuensi pinching lainnya. Sudamala Oranye 1 memiliki produksi tertinggi dengan pemberian AB Mix, sedangkan Maharani F1 pada aplikasi pupuk NPK + Gandasil., A research was conducted at CV. Benih Dramaga from March to July 2023 to study the effect of different pinching frequencies (every 2, 4 and 6 days) and fertilizer types (AB Mix and NPK + Gandasil) on marigold growth and flower yield. Three separate experiments were carried out based on planting material, namely cuttings of var. Sudamala Oranye 1, as well as cuttings and seeds of var. Maharani F1. The field experiments for cutting were carried out as factorial randomized block design (RCBD) with three replications in all possible combinations, while from seed used RCBD with seven replications and fertilizer types as the factor. The results revealed that pinching frequency significantly influenced the percentage of yielding plants, also diameter and fresh weight of individual flower of Sudamala Oranye 1. Fertilizer type significantly affected the percentage of yielding plants, leaf and flower petal color of both varieties, and the percentage of bacterial wilt-infected plants in Sudamala Oranye 1. Additionally, the number of shoots per week, total new shoots, fresh weight of flower per plant, and yield per hectare of Maharani F1 were significantly impacted. Interactions were observed in some growth parameters of Sudamala Oranye 1. In both varieties, pinching every 2 days produced the highest yield components, although not significantly different from other pinching frequencies. The highest Sudamala Oranye 1 flower yield was found with application of AB Mix, while NPK + Gandasil showed the highest yield in Maharani F1.
Keyword: AB Mix, Gandasil, Frekuensi pinching, NPK, Stek marigold, Pinching frequency, Shoot cuttings of marigold

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: