Judul: Drought Stress Effect on Red Chili Pepper Growth and Development
Abstrak: Cekaman kering dapat menyebabkan berbagai macam perbedaan morfologi dan fisiologi meskipun tanaman berasal dari spesies dan varietas yang sama. Perbedaan ini disebabkan oleh mekanisme tanaman dalam beradaptasi dan bertahan hidup di lingkungan kering. Respon yang paling umum terjadi adalah penurunan laju pertumbuhan termasuk perubahan pada daun, yang menyebabkan penurunan angka produksi. Studi tentang pengaruh cekaman kering sering dilakukan saat atau setelah periode produksi untuk menentukan pengaruh cekaman pada produksi. Namun, penelitian ini berfokus pada pengaruh cekaman kering terhadap respon pertumbuhan pada vase vegetatif tanaman. Tanaman yang digunakan adalah empat varietas cabai merah yang terdiri atas dua varietas hibrida dan dua varietas bersari bebas (OPV). Penelitian ini bertujuan mengidentifikasi pengaruh cekaman kering pada varietas cabai merah yang berbeda selama masa vegetatifnya. Rancangan percobaan yang digunakan adalah rancangan acak lengkap (RAL) dan rancangan kelompok acak lengkap (RKAL). Cabai merah hibrida, Gada dan Panex, serta cabai merah OPV, Anies dan Seloka, ditanam dengan perlakuan penyiraman konstan dan perlakuan kering. Pengamatan pertumbuhan dilakukan dalam dua tahap percobaan yang terpisah. Pengamatan percobaan tahap 1 dilakukan pada usia 3 minggu setelah tanam (MST) hingga 7 MST. Selanjutnya, pengamatan percobaan tahap 2 dilakukan pada usia 3–11 MST. Tidak ada perbedaan nyata pada aspek pertumbuhan dan perkembangan yang diamati antar interaksi perlakuan dan varietas secara statistik, namun ditemukan peringkat rataan yang konstan terhadap variabel pertumbuhan tinggi tanaman, jumlah buku, lingkar batang, jumlah cabang, panjang akar, bobot basah akar, bobot basah total, bobot kering total, jumlah bunga, jumlah buah, bobot basah buah, dan bobot kering buah. Perbedaan nyata secara statistik ditemukan masing-masing pada faktor varietas dan perlakuan cekaman kering. Pengelompokan berdasarkan ukuran polybag (20x20 cm dan 40x40 cm) tidak memberikan pengaruh nyata terhadap variabel yang diamati. Varietas Panex (hibrida) dan Seloka (OPV) menunjukkan peringkat rataan respon pertumbuhan tertinggi pada cekaman kering. Sementara itu, varietas Anies menunjukkan peringkat rataan pertumbuhan dan perkembangan terendah pada kondisi lingkungan tercekam kering., Drought stress can bring various morphological and physiological differences despite being in the same species and variety. These differences are caused by plant mechanism to adapt and survive in dry environment. The most common response is the decrease of growth rate including changes of leaves, which ultimately reduce the number of production. Studies on drought stress effects are often done during or after the production period to confirm its effect on production. However, this research focused on drought stress effects on plant growth response during its vegetative phase. The plants used are four varieties of red chili pepper, consist of two varieties of hybrid varieties and two varieties of open pollinated varieties (OPV). The purpose of this study is to identify drought stress effects on different varieties of red chili peppers during its vegetative phase. The experimental design used was randomized complete design and randomized complete complete block design. Hybrid chili peppers, Gada and Panex, and OPV chili peppers, Anies and Seloka, were planted with constant watering and drought treatment. Growth observations were conducted in two independent batches. The first batch were observed from age 3 weeks after planting until 7 weeks after planting. After that, the second batch was observed from age 3
Keyword: Anies IPB, Capsicum annuum L., Gada F1, Panex 100 F1, Seloka IPB

Judul: The Effect of Shading Time for Growth and Yield of  Chili Pepper (Capsicum frutescens L.)
Abstrak: Cabai rawit (Capsicum frutescens L.) merupakan salah satu tanaman hortikultura di Indonesia yang memiliki nilai ekonomi tinggi dan tingkat kebutuhan yang tinggi. Permasalahan utama dalam produksi tanaman cabai rawit adalah harga penjualan cabai rawit yang berfluktuasi. Fluktuasi harga cabai rawit ini seringkali tidak menguntungkan petani karena pada saat produksi melimpah harga cabai rawit turun, tetapi pada produksi yang sedikit harga cabai rawit naik. Penelitian ini bertujuan mengetahui pengaruh waktu pemberian naungan terhadap pertumbuhan dan hasil tanaman cabai rawit pada lokasi yang berbeda. Penelitian dilakukan di Kebun Percobaan Leuwikopo, IPB pada Agustus 2022 hingga Maret 2023. Rancangan percobaan menggunakan Nested (tersarang) Rancangan Kelompok Lengkap Teracak (RKLT) 2 faktor. Faktor pertama yaitu lokasi yang terdiri dari lahan A (samping Green House) dan lahan B (lahan antara kelas). Faktor kedua yaitu naungan yang terdiri dari 3 taraf, yaitu tanpa naungan, naungan 50%, dan naungan 90%. Percobaan menggunakan 3 ulangan, sehingga terdapat 18 satuan percobaan. Setiap ulangan terdiri dari 54 tanaman, sehingga jumlah tanaman yang ditanam sebanyak 972 tanaman dengan 10 tanaman contoh pada setiap ulangan. Hasil penelitian menunjukkan perlakuan intensitas naungan mempengaruhi penundaan panen tanaman cabai rawit. Pemberian naungan mampu menunda panen cabai rawit di lahan lebih lambat hingga 12 hari. Intensitas naungan 50% dan lokasi N2 memberikan hasil yang terbaik pada parameter yang diuji. Hasil panen dan kandungan capcaisin tanaman cabai rawit tertinggi didapatkan pada tanaman kontrol atau tidak ternaungi. Jarak tanam perlu diperhatikan agar lebar kanopi antar tanaman tidak tumpang tindih., Chili pepper (Capsicum frutescens L.) is one of the horticultural crops in Indonesia that has high economic value and high demand. The main problems in the production of chili pepper is fluctuating selling price. These fluctuations often unprofitable for farmers because when production is abundant will be falling price, but when production is low there will be rises price of chili pepper at different locations. This study aimed to determine the effect of shading time for the growth and yield of chili pepper. The experiment was conducted in Leuwikopo Experimental Farm, IPB from August 2022 to Maret 2023. The experimental design used a 2-factor Nested Complete Randomized Group Design (RKLT). The first factor was location which consisted of land A (next to Green House) and land B (between classes). The second factor was shading which consisted of 3 levels, namely no shade, 50% shade, and 90%. The experiment was carried out in 3 replications, so there were 18 experimental units. Each replicates consisted of 54 plants, so the number of plants was 972 plants with 10 sample plants in each replicates. The results showed that shading intensity was affected the harvest delay of chili pepper. Shade treatment was able to delay the harvest of chili pepper in the field up to 12 days slower. Shading intensity of 50% and location of N2 gave the best results for the parameters tested. The highest yields and capsaicin content of chili pepper were obtained from unshaded plants. Spacing needs to be considered so the width of the canopy between plants does not overlap.
Keyword: growing environtment, price, harvest age, growth, productivity

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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