Judul: Seed-Borne Pathogens and the Effects of Sorting and Electrotherapy on Soybean Viability
Abstrak: Kedelai merupakan komoditas pangan penting di Indonesia. Produksi kedelai cenderung menurun dari tahun 2017 hingga 2022. Produksi kedelai nasional belum mampu mencukupi kebutuhan dalam negeri sehingga pemerintah mengimpor kedelai sekitar 2,48 juta ton pada tahun 2021. Patogen terbawa benih menjadi penting karena merugikan secara kualitas dan kuantitas produksi tanaman kedelai. Penelitian ini bertujuan untuk mengidentifikasi bakteri dan cendawan terbawa benih kedelai dan mengetahui pengaruh elektroterapi terhadap viabilitas benih hasil sortasi. Metode meliputi isolasi dan identifikasi bakteri dan cendawan terbawa benih dengan metode pengenceran dan blotter test, pengujian Gram, uji reaksi hipersensitivitas, dan perlakuan elektroterapi untuk benih yang dibedakan dalam benih tanpa gejala, bergejala dan acak hasil sortasi. Isolat bakteri terbawa benih kedelai berdasarkan karakter morfologi dan fisiologinya teridentifikasi sebagai Xanthomonas sp., Pseudomonas sp., dan Ralstonia solanacearum. Sedangkan isolat cendawan teridentifikasi sebagai Aspergillus flavus, A. niger, Trichoderma sp., Sclerotium rolfsii, dan Penicillium sp.. Elektroterapi terhadap benih kedelai dilakukan dengan tegangan 12 V DC dan arus 1 A pada konsentrasi NaCl 1 M dalam waktu 0, 5, 10, 15, dan 20 menit pada masing-masing sortasi benih memberikan pengaruh negatif viabilitas benih dan panjang tajuk tanaman. Dua penyakit ditemukan pada tanaman selama 11 MST dari benih kedelai hasil elektroterapi, yaitu bercak daun (Curvularia sp.), dan penyakit mosaik yang diduga Soybean mosaic virus, Soybean is an important food commodity in Indonesia. Soybean production has tended to decline from 2017 to 2022, unable to meet national demand. As a consequence, the government imported around 2.48 million tons of soybeans in 2021. Pathogens carried by seeds are important because they harm the quality and quantity of soybean production. This research aims to identify bacteria and fungi carried by soybean seeds and to determine the effect of electrotherapy on the viability of sorted seeds. The methods include isolating and identifying bacteria and fungi carried by seeds using dilution and blotter test, Gram testing, hypersensitivity reaction testing, and seed electrotherapy distinguished in symptomless, symptomatic, and randomly sorted seeds. Isolates of bacteria carried by soybean seeds based on morphological and physiological characteristics were identified as Xanthomonas sp., Pseudomonas sp., and Ralstonia solanacearum. The identified fungi are Aspergillus flavus, A. niger, Trichoderma sp., Sclerotium rolfsii, and Penicillium sp. Electrotherapy on soybean seeds was conducted at 12 V DC and 1 A with 1 M NaCl concentration for 0, 5, 10, 15, and 20 minutes on each seed sorting showed negative effect on seed viability and plant shoot length. Two diseases were found in plants during the planting period over 11 weeks after planting are leaf spot (Curvularia sp.) and disease suspected to be caused by Soybean mosaic virus.
Keyword: kedelai, elektroterapi, patogen, Bacteria, electric current, fungi, physical/mechanical treatment, soybean production., Bacteria, electric current, fungi, physical/mechanical treatment, soybean production

Judul: Shelf  Life of Soybean Seed (Glycine max) with Pre-Storage Treatment at Different Storage Temperatures
Abstrak: Kualitas benih sangat penting dalam produksi kedelai. Mutu benih dapat menurun pada saat penyimpanan, pemanenan, pengangkutan, dan penyimpanan di gudang. Penelitian ini bertujuan mengetahui pengaruh perlakuan pra simpan terhadap mutu dan daya simpan benih kedelai. Penelitian dilaksanakan pada bulan Februari sampai Agustus 2023 di Laboratorium Penyimpanan dan Pengujian Mutu Benih Departemen Agronomi dan Hortikultura, Fakultas Pertanian, Institut Pertanian Bogor. Penelitian dilakukan dengan rancangan acak lengkap (RAL) Split-plot dengan tiga ulangan. Petak utama adalah suhu simpan yaitu suhu AC (15 - 19℃) dan suhu kamar (26 - 28℃). Anak petaknya adalah perlakuan pra simpan yaitu: kontrol, cuci – jemur, jemur, oven dan fungisida. Kadar air benih pada penyimpanan suhu kamar dan AC hingga 6 bulan setelah simpan masih dibawah 11%. Suhu simpan secara umum tidak berpengaruh nyata terhadap viabilitas, vigor dan kesehatan benih kedelai. Serangan cendawan Aspergillus banyak ditemui pada penyimpaanan benih kedelai. Perlakuan fungisida mampu mempertahankan daya berkecambah 80% hingga bulan setelah simpan. Perlakuan fungisida menunjukkan adanya potensi sebagai pra perlakuan penyimpanan benih kedelai. Benih tanpa perlakuan kehilangan daya berkecambah dibawah 80% pada 3 bulan setelah simpan, sedangkan pada akhir penyimpanan hanya 67%. Perlakuan jemur dapat dijadikan sebagai alternative untuk melindungi benih dari serangan cendawan dengan daya berkecambah lebih dari 80% hingga 5 bulan simpan dan pada 6 bulan simpan memiliki daya berkecambah 74. Penelitian ini menunjukan adanya potensi perlakuan fungisida sebagai perlakuan pra penyimpanan benih kedelai., The seed quality is crucial for soybean production. Seed quality can decrease during storage, harvesting, transportation and werehouse storage. This study aimed to identifiy the effect of seed treatment on the quality and storability of soybean seeds. The research was conducted from February to August 2023 at the Seed Storage and Quality Testing Laboratory, Department of Agronomy and Horticulture, Faculty of Agriculture, Bogor Agricultural University. The research was arranged in a split plot design and a completely randomized design with three replications. The main plot was temperature, that is air conditioning temperature (15-19℃) and room temperature (26-28℃). The subplots was subjected to seed treatment: control, rinse-drying, drying, oven and fungicide. Seed moisture at at both temperatures was under 11% until six months after storage (MAS). Generally, storage temperature does not significantly affect seed viability, vigor, or health. Aspergillus infection was the dominant fungus in soybean seeds during storage. Fungicide treatment maintained a germination percentage of approximately 80% at 6 MSA. Otherwise, the control lost germination under 80% at 3 MSA, and at the end of storage, the germination percentage was approximately 67%. Drying treatment could be an alternative to protect the seed from fungal infection, with a germination percentage of more than 80% at 5 MSA and 74% at 6 MSA. This finding shows the potential of fungicide treatment as a pra treatment for soybean seed storage.
Keyword: Cendawan, Fungisida, Pemanasan, Penjemuran, Viabilitas

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology