Judul: Mempelajari Pengaruh Kandungan Air Tanah Dan Kecepatan Pembajakan Terhadap Kebutuhan Tenaga Tarik Bajak Di Pabrik Gula Jajtitujuh, Jati Barang- Cirebon
Abstrak: Tujuan dari penelitian ini adalah untuk mempelajari pengaruh kandungan air tanah dan kecepatan pembajakan ter- hadap kebutuhan tenaga tarik bajak, tenaga tahanan guling roda, slip roda traktor dan sifat fisik tanah yang melipu- ti porositas tanah sebelum dan sesudah pembajakan serta daya sanggah tanah ("cone index") sebelum dan sesudah pem- bajakan. Metoda penelitian menggunakan rancangan petak terbagi satu kali dengan analisa faktorial. Faktor pertama adalah Kandungan air tanah sebagai petak utama yang terdiri dari tiga taraf dan faktor kedua adalah kecepatan pembajakan sebagai subpetak sebanyak tiga taraf pula. Masing-masing unit percobaan mempunyai ulangan sebanyak tiga kali. Secara umum hasil penelitian ini menunjukkan bahwa : kandungan air tanah berpengaruh sangat nyata terhadap ke- butuhan tenaga tarik bajak, tenaga tahanan guling roda, slip roda traktor, porositas tanah sebelum dan sesudah pem- bajakan serta daya sanggah tanah sebelum dan sesudah pem- bajakan. Kecepatan pembajakan berpengaruh sangat nyata ...
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Judul: Pengaruh kadar air tanah dan kecepatan  pembajakan terhadap kebutuhan tenaga tarik di PT Kebun Grati Agung Pasuruan
Abstrak: Penelitian ini dilakukan pada tanah liat berlempung di lokasi PT Kebun Grati Agung, Pasuruan. Tujuan penelitian adalah untuk melihat pengaruh tingkat kandungan air tanah terhadap kebutuhan tenaga tarik, kekerasan tanah, "dry bulk densitas", slip dan tahanan guling pada tingkat pembajakan tanah. Hasil penelitian menunjukkan, bahwa kecepatan pembajakan B2, B3 dan B4 didapatkan tenaga yang minimum masing-masing 25.4 Hp, 44.58 Hp dan 47.58 Hp untuk menarik bajak piring dengan lebar pembajakan 110 cm dan kedalaman pembajakan rata-rata 25 cm, diperoleh pada kandungan air tanah 30 persen basis basah. Makin tinggi kecepatan makin besar tenaga yang dibutuhkan .. Slip roda traktor pada kadar air tanah 10 sampai 30 persen basis basah paling kecil yakni 15.26 dan 11.62 persen serta 13.76 persen, ini terjadi pada kecepatan gigi B4. Hubungan tahanan guling dengan slip berbanding lurus, semakin besar tahanan guling semakin bertambah besarnya slip roda traktor. Terjadi penurunan kekerasan tanah sebesar 40.59 ...
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Judul: Systematics of Desmos (Annonaceae) in Malesia
Abstrak: Desmos is a woody climbing genus of Annonaceae which has been widely used as traditional medicine in several countries such as China, Indo-China, Thailand, and Peninsular Malaysia to treat dysentery, vertigo, fever, and postpartum. Phylogenetic studies on Desmos showed a close relationship between Desmos and Dasymaschalon. They share similar moniliform monocarpic fruits, but their flowers are different. It has been debated among Annonaceae researchers whether both genera should be treated as the same or distinct genus. Therefore, investigation on the taxonomic delimitation of Desmos species and Dasymaschalon will be necessary. Plastid genome (plastome) identification, leaf epidermal section of Desmos species and Dasymaschalon species, a taxonomic revision of Desmos in Malesia using morphological data, the spatial distribution of Desmos species in Malesia, and morphological and genetic variation in Desmos chinensis population using ISSR marker were used to investigate taxonomic delimitation of Desmos. Plastome study of Desmos chinensis and Dasymaschalon dasymaschalum was carried out to determine the origin, evolution, phylogenomics, and identify marker candidates for Desmos and Dasymaschalon or with other genera in Annonaceae. We discovered that the plastome of Desmos chinensis was circular with the size of 167,677 bp (smaller than Dasymaschalon dasymaschalum), consist of 111 genes, including 78 protein-coding genes, 29 transfer RNAs, and 4 ribosomal RNAs. The plastome showed a typical quadripartite structure, i.e., large single copy (LSC), small single copy (SSC), and two inverted repeats (IRs). The plastome of Dasymaschalon dasymaschalum was 191,488 bp in length, which also exhibited a typical quadripartite structure (LSC, SSC, and two IRs). Desmos chinensis and Dasymaschalon dasymaschalum showed different copies of accD, ndhD, ndhF, rps18, and ycf2. Protein coding genes of rpoB, rpoC1, rbcL, matK, rpl32, infA, and rpl36 were identified based on nucleotide diversity, sequence variability, and parsimony-informative sites. The genes are defined as molecular marker candidates of plastome for phylogenetic, barcoding, and population genetic research. We predicted that Desmos chinensis and Dasymaschalon dasymaschalum separated at ca. 64 million years ago during the Paleocene. Leaf anatomical feature study was carried to support the taxonomic delimitation of interspecific Desmos and intergeneric of Desmos and Dasymaschalon. Leaf anatomy in the paradermal section of 20 taxa (12 species of Desmos, eight species of Dasymaschalon) have been carried out. According to the leaf epidermal section, Desmos and Dasymaschalon are two distinct genera mainly distinguished based on the anticlinal wall undulation of epidermal cells and supported by variation of the crystal type and size. The anticlinal wall undulation of Desmos was almost straight to slightly wavy and never sinuous; meanwhile, Dasymaschalon varies from almost straight to deeply sinusoid. The crystals of Desmos consist of rhombohedral, druse type A, and druse type B crystals, whereas Dasymaschalon has prism, druse type A, druse type B, and druse type C crystals. The recent taxonomic revision using the morphological data was mainly based on the examination of about 1374 specimens from BO, L, WAN, ANDA, SING, SAN, K, P, HUH herbaria. The Desmos species in Malesia consists of eight species: D. acutus, D. chinensis, D. chryseus, D. dunalii, D. pedunculosus, D. subbiglandulosus, two new records: D. lawii and D. macrocarpus, and one
Keyword: Dasymaschalon, Desmoid clade, Magnoliid, plastid genome, phylogenomics analysis