Judul: Utilization of Indigenous Vegetables as an Intercrop Plant to Increase the Productivity of Lowland Rice
Abstrak: Sayuran indigenous adalah sayuran asli daerah yang telah banyak diusahakan dan dikonsumsi atau sayuran introduksi yang telah berkembang lama dan dikenal masyarakat. Permasalahan yang ada di lapangan saat ini adalah banyaknya penggunaan bahan kimia ataupun herbisida untuk menekan gulma yang ada di lapangan terutama lahan padi. Penelitian ini bertujuan untuk mendapatkan informasi dan menganalisis tanaman sayuran indigenous yang mampu menekan populasi gulma di lahan padi guna meningkatkan produktivitas lahan sawah. Penelitian dilaksanakan di lahan Sawah Kampung Lebak Gunung, Desa Benteng, Ciampea, Bogor, Jawa Barat, Institut Pertanian Bogor, mulai bulan Januari 2020 - Mei 2020. Penelitian menggunakan rancangan kelompok lengkap teracak (RKLT) faktor tunggal. Perlakuan sayuran indigenous yang diuji, yaitu genjer (Limnocharis flava), gonda (Sphenoclea zeylanica), kangkung (Ipomea aquatica), dan semanggi (Marsilea crenata) serta kontrol (tanpa sayuran). Percobaan diulang sebanyak 4 kali sehingga total hasil 20 satuan percobaan. Hasil penelitian menunjukan bahwa sayuran indigenous yang ditanam sebagai tanaman sela mampu menekan gulma, tidak menghambat pertumbuhan tanaman padi, dan tidak mengganggu produktivitas hasil padi. Penanaman sayuran indigenous sebagai tanaman sela dapat meningkatkan produktivitas lahan padi sawah. Sayuran indigenous yang bernilai ekonomi lebih tinggi dan tidak menggangu produktivitas hasil padi adalah sayuran genjer (Limnocharis flava)., Indigenous vegetables are native vegetables to the area that have been being widely cultivated and consumed or introduced vegetables that have developed for a long time and wellknown to the public. The problem that exists in the field today is the use of chemicals or herbicides to suppress weeds in the field, especially rice fields. This study aimed to obtain information and analyze indigenous vegetables that could suppress weed populations in rice fields in order to increase the productivity of lowland rice. The research was conducted in the rice fields of Kampung Lebak Gunung, Benteng Village, Ciampea, Bogor, West Java, Bogor Agricultural University, from January 2020 - May 2020. The study used a single factor randomized complete group design (RKLT). The observation of indigenous vegetables tested were genjer (Limnocharis flava), gonda (Sphenoclea zeylanica), water spinach (Ipomea aquatica), clover (Marsilea crenata) and control (without vegetables). The observations were repeated 4 times, resulting in a total of 20 trials. The results showed that the indigenous vegetables grown as intercrops were able to suppress weeds, did not inhibit the growth of rice plants, and did not interfere with the rice productivity. Indigenous vegetables as an intercrop can increase the productivity of lowland rice. The indigenous vegetable which had higher economic value and did not interfere the rice productivity among other vegetables was genjer (Limnocharis flava).
Keyword: indigenous vegetables, rice weed, intercropping, riceland productivity

Judul: Multicanopy Cultivation of Four Rice Varieties with Jajar Legowo Planting Distances at KP Babakan Dramaga
Abstrak: Padi (Oryza sativa) merupakan salah satu tanaman pangan terpenting di Indonesia. Peningkatan konsumsi beras tidak sebanding dengan luas panen di Indonesia. Penelitian ini bertujuan mempelajari pengaruh sistem budidaya dan varietas terhadap peningkatan produksi padi di Kebun Percobaan Sawah Baru IPB, Babakan Dramaga. Penelitian ini menggunakan RKLT faktorial dengan dua faktor yaitu sistem budidaya (monokultur, multikanopi sisip 1, multikanopi sisip 2) dan varietas (INPARI 32, INPARI 33, INPARI 43, IPB 9G sebagai tanaman sisipan). Hasil penelitian menunjukkan bahwa terdapat interaksi kedua perlakuan yang berpengaruh pada tinggi tanaman saat berumur 8 MST, tinggi batang saat panen, sudut kemiringan daun bendera. Pengaruh tunggal sistem budidaya signifikan terhadap tinggi tanaman padi saat berumur 8 MST, jumlah anakan, panjang daun dan sudut kemiringan daun bendera, bobot kering tajuk dan bobot kering malai saat panen, jumlah malai per rumpun, jumlah gabah isi per malai, bobot gabah per rumpun. Pengaruh tunggal varietas signifikan terhadap tinggi tanaman, jumlah anakan, panjang daun dan sudut kemiringan daun bendera, bobot kering malai, panjang malai, jumlah gabah per malai, jumlah gabah isi per malai, bobot 1000 butir, dan bobot gabah per rumpun., Rice (Oryza sativa) is one of the most important food crops in Indonesia. The increase in rice consumption is not proportional to the harvested area in Indonesia. This study aims to study the effect of cultivation systems and varieties on increasing rice production in the Experimental Garden of Sawah Baru IPB, Babakan Dramaga. This study used a factorial RKLT with two factors, namely the cultivation system (monoculture, multi-canopy insertion 1, multi-canopy insertion 2) and varieties (INPARI 32, INPARI 33, INPARI 43, IPB 9G as insertion plant). The results showed that there was an interaction between the two treatments that affected plant height at 8 WAP, stem height at harvest, flag leaf tilt angle. The single effect of the cultivation system was significant on rice plant height at the age of 8 WAP, number of tillers, leaf length and angle of inclination of flag leaves, crown dry weight and panicle dry weight at harvest, number of panicles per clump, number of filled grain per panicle, grain weight per clump. The single varietal effect was significant on plant height, number of tillers, leaf length and angle of inclination of flag leaf, panicle dry weight, panicle length, number of grain per panicle, number of filled grain per panicle, 1000 grain weight, and grain weight per clump.
Keyword: insertion, interaction, monoculture, production, productivity

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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