Judul: Growth and Yield Response of Kangkong (Ipomoea reptans Poir) to the Aplications of Kascing, Bioboost, and Their Residues, Growth and Yield Response of Kangkong (Ipomoea reptans Poir) to the Aplications of Kascing, Bioboost, and Their Residues
Abstrak: Penelitian ini bertujuan untuk mengetahui respon pertumbuhan dan hasil kangkung terhadap pemupukan kascing dan bioboost beserta residu keduanya. Penelitian ini menggunakan Rancangan Kelompok Lengkap Teracak Faktorial. Faktor pertama adalah pemupukan kascing (K) dan residunya (RK), yaitu tanpa kascing (K0 dan RK0), kascing 300 g per lubang tanam (K1 dan RK1), dan kascing 450 g per lubang tanam (K2 dan RK2). Faktor kedua adalah pemupukan bioboost (B) dan residunya (RB), yaitu tanpa bioboost (B0 dan RB0), 2 l /ha (B1 dan RB1), 4 l/ha (B2 dan RB2), dan 6l/ha (B3 dan RB3). Kedua faktor diuji terhadap kontrol negatif (tanpa pemupukan) dan kontrol positif (pemupukan anorganik susulan) setiap perlakuan diulang sebanyak tiga kali sehingga seluruhnya terdapat 39 satuan percobaan dengan luas masing-masing petakan 1,5 m2. Penanaman dilakukan sebanyak dua kali. Penanaman kedua dimaksudkan untuk mengamati residual effect kedua faktor. Hasil penelitian ini menunjukkan kangkung terbaik terdapat pada interaksi 450 g kascing per lubang tanam dan 6 liter bioboost per hektar dengan potensi hasil mencapai 23,67 ton per hektar pada penanaman pertama dan 17,73 ton per hektar pada penanaman kedua yang memanfaatkan residu pemberian kascing dan bioboost sehingga tidak perlu melakukan pemupukan pada penanaman kedua., This study aims to determine the growth response and yield of kangkong to vermicompost and bioboost fertilization and their residues. This study used a Factorial Randomized Complete Group Design. The first factor was fertilization with vermicompost (K) and its residue (RK), ie without vermicompost (K0 and RK0), 300 g vermicompost per planting hole (K1 and RK1), and 450 g vermicompost per planting hole (K2 and RK2). The second factor was fertilization with bioboost (B) and residue (RB), namely without bioboost (B0 and RB0), 2 l/ha (B1 and RB1), 4 l/ha (B2 and RB2), and 6 l/ha (B3 and RB2). RB3). Both factors were tested against negative control (without fertilization) and positive control (follow-up inorganic fertilization). Each treatment was repeated three times so that in total there were 39 experimental units with an area of 1,5 m2 each. Planting was carried out twice. The second planting is intended to observe the residual effect of the two factors. The results of this study showed that the best kangkong was found in the interaction of 450 g of vermicompost per planting hole and 6 liters of bioboost per hectare with a potential yield of 23, 67 tonnes per hectare in the first planting and 17,73 tonnes per hectare in the second planting using residues of vermicompost and bioboost so there is no need to fertilize the second planting.
Keyword: dose, inorganic, mandailing natal, organic, yield potential, anorganik, dosis, mandailing natal, organik, potensi hasil

Judul: Response of Three Varietas Water Spinach (Ipomea reptans  Poir) to Increased NPK Fertilization
Abstrak: Kangkung darat (Ipomea reptans Poir) merupakan komoditas hortikultura yang banyak dibudidayakan dan digemari karena waktu panennya yang cepat dan mudah dibudidayakan. Namun seiring berjalannya waktu produksi tanaman kangkung terus menurun setiap tahunnya. Penggunaan pupuk majemuk dan pemilihan varitas unggul merupakan salah satu solusi dan alternatif untuk meningkatkan produksi dan efisiensi budidaya. Penelitian ini bertujuan mendapatkan informasi interaksi dan respon tiga varietas kangkung terhadap pemberian dosis pupuk NPK yang berbeda pada pertumbuhan dan hasil. Penelitian ini dilakukan pada bulan April hingga Mei 2024 di Desa Cikura, Kabupaten Banjarnegara, Jawa Tengah. Penelitian ini menggunakan rancangan kelompok lengkap teracak dengan dua faktor dosis dan varietas yang terdiri atas tiga ulangan. Faktor pertama yaitu dosis pemupukan dengan 4 taraf dosis pemupukan yaitu 0 NPK, 0,5 g tan-1 NPK, 1 g tan-1 NPK, dan 1,5 g tan-1. Faktor kedua yaitu varietas menggunakan 3 varietas komersil yaitu Bangkok LP-1, Rajawali, dan Serimpi. Hasil penelitian menunjukkan bahwa dosis pupuk 1,5 g tan-1 mampu meningkatkan tinggi tanaman, jumlah daun dan berat segar tanaman. Varietas Bangkok LP-1 dapat meningkatkan pertumbuhan dan hasil tanaman kangkung. Hasil penelitian menunjukan tidak terdapat interaksi yang nyata antara dosis pupuk NPK dan tiga varietas kangkung terhadap pertumbuhan dan hasil tanaman kangkung, Water spinach (Ipomea reptans Poir) is a horticultural plant widely cultivated and favored due to its quick harvest time and ease of cultivation. Bu, as time goes by, water spinach production continues to decline every year. The use of compound fertilizers and the selection of superior varieties are among the solutions and alternatives to increase production and cultivation efficiency. This study aims to determine the effect of NPK fertilizer dosage on the growth and yield of three varieties of water spinach (Ipomea reptans Poir). The research was conducted from April to May in Cikura Village, Banjarnegara Regency, Central Java. This study used a randomized complete group design with two factors, dose and variety, consisting of three replications. The first factor is the fertilizer dose with 4 levels of fertilizer dose namely 0 NPK, 0.5 g tan-1 NPK, 1 g tan-1 NPK, dan 1.5 g tan-1. The second factor is the variety using 3 commercial varieties, namely Bangkok LP-1, Rajawali, and Serimpi. The research results showed that a fertilizer dose of 1.5 g tan-1 was able to increase plant height, number of leaves and fresh weight of plants. The Bangkok LP-1 variety can increase the growth and yield of kale plants. The results of the research showed that there was no real interaction between the dose of NPK fertilizer and the three varieties of kale on the growth and yield of kale plants.
Keyword: Bangkok LP-1, dosage, interaction

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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