Judul: Effects of Gibberellic Acid (GA3) to Growth, Yield Component, and Yield on Shallot (Allium cepa var. aggregatum) Bima Brebes Variety
Abstrak: Penggunaan ZPT giberelin merupakan faktor pendukung yang memberikan kontribusi dalam peningkatan produktivitas bawang merah. Penelitian ini bertujuan untuk mempelajari pengaruh GA3 pada bawang merah varietas Bima Brebes, dan mendapatkan dosis optimum yang dapat meningkatkan produktivitas. Penelitian ini dilaksanakan pada bulan Maret sampai Mei 2020 di Kabupaten Brebes. Penelitian dilakukan dengan cara foliar spray GA3 dengan 0–2,5 dosis dalam volume semprot 400 L air pada tanaman bawang merah varietas Bima Brebes. Rancangan yang digunakan adalah Rancangan Kelompok Lengkap Teracak faktor tunggal 4 ulangan, terdiri dari 6 perlakuan dosis masing-masing yakni 0; 0,5; 1,0; 1,5; 2,0; dan 2,5 dosis GA3. Hasil penelitian menunjukkan bahwa 0,5–2,0 dosis GA3 secara nyata berhasil meningkatkan tinggi tanaman, bobot 10 umbi, bobot kering per tanaman dan bobot per petak yang memengaruhi dugaan hasil per hektar. Dosis optimum dari hasil analisis regresi menunjukkan pada peubah bobot 10 umbi yakni 1,54 dosis GA3., The use of gibberellin as a growth regulator is a supporting factor that contributes to the productivity of shallots. This research aimed to study the effects of GA3 on Bima Brebes shallots variety, and to get the optimal doses so that it is expected to increase productivity. This research was conducted from March to May 2020 in Brebes Regency. This research used foliar spray of GA3 with 0–2,5 doses in 400 L of water spray volume to Bima Brebes shallots variety. This research used Randomized Complete Block Design in single factor of 4 blocks, consists of 6 doses treatment which 0; 0,5; 1,0; 1,5; 2,0; and 2,5 doses GA3. The results showed that 0,5–2,5 GA3 doses significantly increased plant height, 10 tubers weight, dry plant weight and weight per plot which affected the estimated yield per hectare. The optimum doses from regression analysis results showed on variable of 10 tubers weight is 1,54 GA3 doses.
Keyword: Bima Brebes, foliar spray, GA3, sets, shallots

Judul: Varietal Impact on Growth, Yield, and Water Requirements of Shallot (Allium cepa L. var. aggregatum) in Dryland Cultivation
Abstrak: Bawang merah (Allium cepa L. var. aggregatum) merupakan komoditas hortikultura yang mempunyai prospek pasar yang sangat baik sehingga termasuk ke dalam komoditas unggulan nasional. Penggunaan varietas yang merupakan salah satu cara untuk meningkatkan produktivitas bawang merah. Penelitian ini bertujuan mengetahui pengaruh dari penggunaan empat varietas bawang merah terhadap pertumbuhan, hasil panen, dan kebutuhan air pada tanaman bawang merah yang ditanam di lahan kering. Penelitian dilakukan di Kebun Percobaan Sawah Baru IPB, Dramaga, Bogor, Jawa Barat pada bulan Februari hingga April 2023. Penelitian dilakukan berdasarkan rancangan lengkap kelompok teracak (RKLT) dengan faktor tunggal. Perlakuan dalam penelitian ini adalah diamati adalah 4 varietas bawang varietas yaitu Bima Brebes, Bauji, Tajuk,dan SS Sakato. Hasil penelitian menunjukkan perlakuan varietas berpengaruh sangat nyata terhadap peubah tinggi tanaman pada 2 MST dan 3 MST, jumlah tunas pada 2 MST, 3 MST, 5 MST, dan 6 MST, jumlah daun pada 2 MST dan 4 MST, dan jumlah umbi. Seluruh varietas memberikan hasil yang baik untuk ditanam di lahan kering Bogor. Varietas Bauji merupakan varietas dengan proyeksi produktivitas per hektar tertinggi namun membutuhkan air yang lebih sedikit dari tanam hingga panen dibandingkan varietas Tajuk dan SS Sakato. Jumlah daun berpengaruh terhadap nilai evapotranspirasi, Shallot (Allium cepa L. var. aggregatum) is a horticultural commodity with excellent market prospects, thus being classified as a national superior commodity. The use of varieties is one way to enhance shallot productivity. This research aims to determine the influence of using four varieties of shallots on growth, harvest yield, and water requirements of shallot plants cultivated in dryland. The research was conducted at the Sawah Baru IPB Experimental Garden, Dramaga, Bogor, West Java, from February to April 2023. The research was based on a completely randomized block design with a single factor. The treatments in this study consisted of four observed shallot varieties: Bima Brebes, Bauji, Tajuk, and SS Sakato. The results of the research indicate that the variety treatment significantly influenced the plant height variable at 2 and 3 weeks after planting (WAP), the number of shoots at 2 WAP, 3 WAP, 5 WAP, and 6 WAP, the number of leaves at 2 WAP and 4 WAP, and the number of bulbs. All varieties showed good results for cultivation in dryland in Bogor Regency. The Bauji variety emerged as the most promising in terms of projected productivity per hectare, requiring significantly less water from planting to harvest compared to the Tajuk and SS Sakato varieties. The number of leaves influenced the evapotranspiration value.
Keyword: evapotranspirasi, curah hujan, produktivitas

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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