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MORPHOLOGICAL DESCRIPTION OF UPLAND RICE CULTIVARS IN BENGKULU
No full textKebutuhan beras dalam negeri masih terus meningkat seiring dengan peningkatan jumlah penduduk dan tingkat konsumsi yang masih tinggi. Oleh sebab itu, peningkatan hasil merupakan target utama dalam budidaya padi. Koleksi dan identifikasi sumber plasma nuftah padi gogo lokal sangat perlu dilakukan. Tujuan penelitian ini adalah untuk mengkoleksi, identifikasi, dan mendeskripsikan kultivar padi gogo di provinsi Bengkulu berdasarkan kesamaan morphologi. Sebanyak 41 dari 42 kultivar yang dikoleksi di provinsi Bengkulu dapat tumbuh dengan baik pada lahan kering tanah ultisol dengan rerata curah hujan bulanan selama musim tanam adalah 283 mm, pH 4,6, Al-dd 5,20 me per 100 g, serta C-organik 1,12 %. Komposisi tekstur tanah pada lahan penelitian untuk masing-masing pasir, debu, dan liat adalah 42,05; 25,62, dan 32,33%. Analisa univariate dapat mendeskripsikan rerata serta penyebaran semua peubah yang diamati mulai dari nilai yang minimum sampai maksimum dan nilai rerata disajikan berikut dengan standar deviasi. Secara langsung, potensi hasil tanaman mendeskripsikan bahwa lima kultivar lokal dari koleksi Bengkulu menunjukkan daya hasil tinggi yaitu > 3,8 ton ha antara lain kultivar padi Pendek (G18), Keleng (G32), Abang Pintal (G34), Sedane (G39), and Kijang (G40). Dengan nilai kesamaan morfologi > 90,51%, maka dendogram dari analisa multivariate mengklasterkan 41 kultivar padi gogo asal Bengkulu menjadi lima kelompok
Efficacy of herbicide safeners in corn [Zea mays L.] and grain sorghum [Sorghum bicolor (L.) Moench]
No full textThesis (M.S.)--Michigan State University. Department of Crop and Soil Science, 1992Includes bibliographical references (leaf 41
The study of glyphosate resistance in rigid ryegrass (Lolium rigidum Gaud.) from California
No full textThesis (Ph. D.)--Michigan State University. Department of Crop and Soil Sciences, 2004Includes bibliographical reference
Herbicide Combination for Controlling Glyphosate Resistant Weed
No full textRigid ryegrass merupakan spesies gulma yang memiliki sifat resistensi ganda terhadap beberapa jenis herbisida. Sejauh ini penilitian yang telah dilakukan hanya terfokus pada resistensi terhadap herbisida glyphosat. Hasil penelitian sebelumnya menunjukkan bahwa mekanisme resistensi glyphosat pada gulma ryegrass terjadi karena perubahan pada target site. Biotipe yang resisten (R) berbeda dengan yang sensitif (S) karena perubahan pada sisi targetnya dari aksi glyphosat. Tujuan penelitian ini mengevaluasi apakah biotipe R yang diteliti sebelumnya juga resisten terhadap jenis herbisida lain yang kemungkinan digunakan untuk mengendalikan gulma ryegrass. Penelitian dilakukan di rumah kaca Departemen of Crop and Soil Sciences, Michigan State University, East Lansing, Michigan, USA, untuk membandingkan hasil pengendalian gulma terhadap biotipe R dan S dengan herbisida glyphosate, rimsulfuron + thifensulfuron, kombinasi glyphosate dengan rimsulfuron + thifensulfuron, glufosinate, quizalofop, dan kombinasi glyphosate dengan quizalofop. Pengendalian gulma dengan quizalofop, rimsulfuron + thifensulfuron, and glufosinate nampak sama, menunjukkan bahwa tidak ada resistensi ganda pada biotipe R sehingga gulma ryegrass yang resistensi terhadap glifosat masih dapat dikendalikan dengan herbisida lain yang memiliki cara mekanisme kerja serupa seperti yang diuji pada percobaan ini. Kombinasi herbisida glifosat dengan rimsulfuron + thifensulfuron menunjukkan efek pengendalian yang synergis terhadap biotype R dari ryegrass
THE BASIS FOR GLYPHOSATE RESISTANCE IN RIGID RYEGRASS (Lolium rigidum) FROM CALIFORNIA
No full textThe occurrence of glyphosate-resistant weeds has been reported after more than 20 yr of extensive use. Rigid ryegrass that evolved resistance to glyphosate was found in Australia and in California. Glyphosate-resistant rigid ryegrass plants were collected from northern California and selected through generations 8 and 5 to segregate the most resistant (R) and sensitive (S) biotypes. The eighth generation of R and the fifth generation of S biotypes survived 6.72 and died from 0.11 kg ae ha−1 glyphosate, respectively. The objectives of this study were to evaluate the role of metabolism in the observed resistance, to study the effect of glyphosate on the activity of 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS; EC 2.5.1.19), and to characterize the EPSPS gene in R and S rigid ryegrass. Neither quantitative nor qualitative difference was observed in the metabolism of 14C-glyphosate between the biotypes. Activity of constitutive EPSPS decreased more significantly in the S than R biotype in the presence of 5, 50, 500, and 5,000 µM glyphosate. Inhibition of 50% (I50) of the EPSPS activity by glyphosate was more than 90-fold in S compared to R biotype. Decreased EPSPS sensitivity in the R biotype appeared to be a major contributor to glyphosate resistance in rigid ryegrass from California. Fragments of the EPSPS gene containing 1,320 nucleotides were isolated from mRNA of S and R biotypes. A single nucleotide mutation from cytosine (C) to thymine (T) was identified at nucleotide 301 of the truncated EPSPS gene of the R biotype. This mutation changed the amino acid code from proline (Pro) to serine (Ser), which was similar to that reported for the glyphosate-resistant goosegrass from Malaysia and correlated with glyphosate insensitivity of EPSPS
Identifikasi Genetik Kultivar Padi Gogo dengan Menggunakan Marka RAPD
No full textA research was conducted to identify the genetics of upland rice cultivars using random amplified polimorphic DNA (RAPD) markers. Five out of 60 random primers that capable to amplify the most number of markers were OPE-07 (AGATGCAGCC), OPE-15 (ACGCACAACG), OPH-13 (GACGCCACAC), OPH19 (CTGACCAGCC), and OPM-02 (ACAACGCCTC). The number of markers amplified were 5, 6, 8, 8, and 7, respectively. RAPD-PCR using these 5 primers arranged to DNA templates of 41 rice cultivars amplified 1127 RAPD markers. Polymorphic information content (PIC) of each primer were 0.79, 0.80, 0.87, 0.87, and 0.72, respectively. Cluster analysis using a UPGMA dendogram showed that the 41 cultivars were grouped into 9 clusters with genetic similarity index more than 90 percent
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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