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Influence of cultivar, nitrogen and plant density on production of sorghum planted under different environmental conditions
No full textMSc (Crop Science), North-West University, Mafikeng CampusSorghum is an important cereal crop in the semi-arid regions of sub-Saharan Africa. This study was conducted in the 2016/17 and 2017/18 planting seasons at Mafikeng and Taung, North West Province, South Africa. The main objective of the study was to evaluate the yield and quality of sorghum cultivars as influenced by different nitrogen rates and plant density under different environmental conditions. The experimental design was a split-split plot arrangement fitted into a randomized complete block design with four replicates. The main plot factor comprised of high (33 333 plants/ha) and low (22 222 plants/ha) plant densities. The nitrogen fertiliser rates were 0, 100 and 150 kg N/ha as the sub plot factor. The sub-sub plot factor consisted of two sorghum cultivars, PAN 8625 and PAN 8816. Parameters measured for the study included, plant height, stem diameter, number of leaves per plant, chlorophyll content index, leaf area index, days to 50 and 100 percent flowering, panicle length, panicle mass per plant, panicle mass/ha, 1000 seed mass, biomass yield, grain yield, protein, sugar, starch, oil, fibre, and ash content. In both planting seasons, the cultivar had a significant effect (P < 0.05) on the plant height and stem diameter of the sorghum plant. Sorghum cultivar PAN 8625 had a significantly taller plant and larger stem diameter than PAN 8816. The cultivar also had a significant effect on sorghum panicle mass per plant and sorghum biomass yield in both seasons. Sorghum cultivar PAN 8625 had a significantly higher panicle mass per plant and higher biomass yield than PAN 8816. Significant effects were also obtained on the cultivars for protein and starch content. Sorghum cultivar PAN 8816 had a significantly higher protein and starch content than PAN 8625. Plant density had a significant effect (P < 0.05) on the sorghum leaf area index (LAI), panicle mass per plant and sorghum biomass yield in both seasons. Sorghum planted under high density had a significantly higher value of LAI than those planted under low density. Sorghum planted under high plant density had a significantly higher panicle mass per plant and a higher biomass yield than sorghum under low density. Location had a significant effect (P < 0.05) on the sorghum chlorophyll content index and days to the 50 and 100% flowering in both seasons. Sorghum planted at Mafikeng had a significantly higher chlorophyll content index value than those recorded at Taung during the 2016/17 planting season while in 2017/18 planting season reverse was the case. During the 2016/17 planting season, sorghum planted at Mafikeng flowered significantly earlier than sorghum planted at Taung and contrary in the following season. Location had a significant effect (P < 0.05) on the sorghum 1000 seed mass and grain yield in both seasons. Sorghum planted at Mafikeng had a significantly higher 1000 seed mass than sorghum planted at Taung in both seasons. Grain yield obtained in Mafikeng was significantly higher than value from Taung in 2016/17 planting season. With regards to the oil and starch content of sorghum, location had a significant effect in 2017/18 season; where Sorghum planted at Mafikeng had a significantly higher oil and starch content than sorghum planted at Taung. Mafikeng offers a better nutritive value for the sorghum produced than the one planted in Taung due to favourable weather conditions especially the rainfall. It is therefore recommended that sorghum is cultivated in Mafikeng.Master
The response of three drybean cultivars to different phosphorus fertilizer rates and environmental conditions
Get PDFMSc (Crop Science), North-West University, Mafikeng CampusDrybean is a grain legume, which, through biological nitrogen fixation, is important to humans and animals as a valuable nutrient and for the improvement of the soil. Research was conducted to establish the response of three drybean cultivars to varying application rates of phosphorus fertilizer and to varying environmental conditions. The study was conducted during the 2017/2018 planting season at three locations, namely Taung, Mafikeng and Ventersdorp, in the North West province of South Africa that differed in terms of their environmental conditions. The research examined three drybean cultivars (PAN 123, PAN 148 and PAN 9292) at three sites (Taung, Ventersdorp and Mafikeng), and under five application rates of single superphosphate fertilizer, which differed according to each location (Taung = 0, 30, 45, 60 and 75 kg P/ha⁻¹, Ventersdorp = 0, 45, 60, 75 and 90 kg P/ha⁻¹ and Mafikeng = 0, 110, 114, 118 and 120 kg P/ha⁻¹). All the treatment combinations were laid out in a randomized complete block design (RCBD); with four replications. The assessed growth parameters include plant height, the number of leaves per plant, the chlorophyll content of the leaves, the quantity of nodules and the root length. The results from the research confirmed that PAN 9292 presented with the tallest plants and a larger range of nodules per plant than the other cultivars. PAN 123 produced a larger quantity of leaves per plant, higher chlorophyll content and longer roots length. The results of the research additionally confirmed that the drybean planted at Taung produced stronger growth parameters compared to the other location. The results further revealed that while the grain quality of PAN 123 was higher in ash and crude fibre content, PAN 148 had higher starch content and PAN 9292 had a better fat content. However, none of the cultivars confirmed any significant effect on drybean protein content. The interaction of cultivar × location had a significant effect at the drybean starch content. Chapter 1 presents an introduction and background to the study, focusing on the problem statement, a justification for the study and the aims and objectives of the study. Chapter 2 covers the literature review of the study. Chapter 3 includes the materials used and the methods applied, as well as the effects of phosphorus fertilizer rate, cultivar and location on drybean growth parameters, while Chapter 4 deals with the effects of phosphorus fertilizer rate, cultivar and location on drybean yield. Chapter 5 is about the effects of phosphorus fertilizer rate, cultivar and location on the grain quality of the drybean. Chapter 6 concludes with a discussion on the research findings and recommendations based on the results of the study.Master
Sweet corn production and soil chemical properties under different management practices in dryland conditions of South Africa
No full textA field trial involving sweet corn was carried out at the University of Limpopo experimental farm over two-summer production seasons. The trial was conducted to assess the productivity of sweet corn under different management practices. Treatments consisted of cowpea varieties (Pan 311 and Red caloona), cropping systems (sole and intercropping) and cowpea-leaf pruning regimes (pruning and un-pruned). All treatment combinations were laid out in a randomized complete block design with four replicates. Growth and yield data were collected from sweet corn during the course of the trial. During 2005/06 planting season, sweet corn intercropped with Red caloona gave higher grain yield of 770 kg ha-1 than Pan 311 intercropped plots. Similarly during 2006/07 planting season, sweet corn under Red caloona intercrop also had higher grain yield of 944 kg ha-1 than under Pan 311 intercrop while sole sweet corn plots had higher grain yield of 1115 kg ha-1 than intercropped plots. The cowpea variety (Red caloona) should be considered as the suitable variety for intercropping with sweet corn, when ears and grain yield of sweet corn are desired. Sweet corn and cowpea have great ability to reduce the amount of fertilizer N and K in the soil after their harvest
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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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