1,720,955 research outputs found
Perpetuation and Management of Alternaria solani (Ellis and Martin) Jones and Grout Causing Early Blight of Potato in Kashmir
No full textThe present study on perpetuation and management of Alternaria solani, causing early blight of potato in Kashmir was conducted during 2008 to 2009. An extensive survey conducted in four districts of Kashmir Valley viz., Budgam, Baramulla, Srinagar and Shopian revealed prevalence of early blight of potato in all the localities surveyed. Mean disease incidence and intensity of 24.54 and 13.84 per cent were recorded in the year 2008 and that of 28.23 and 15.98 per cent during the year 2009, respectively. The disease was characterised by small irregular to circular dark brown spots on the lower leaves measuring approximately 0.5 mm in size. The spots on coalescing formed irregular patches, which later on resulted in complete blighting of leaves. The causal fungus was isolated and identified as Alternaria solani (Ellis & Martin) Jones and Grout. The maximum apparent infection rate of 0.155 and 0.165 unit/day was recorded during the second fortnight of June in 2008 and 2009, respectively. Weather factors viz., temperature, relative humidity and rainfall were positively correlated with disease intensity (66.50 per cent contribution). The pathogen perpetuated as mycelium and conidia throughout winter on diseased leaves left on the ground surface and on diseased potatoes kept in ambient store. The number of spores cm-2 leaf area and the viability of spores decreased with increase in depth of placement in soil. Maximum spores production on overwintered leaves and potatoes were observed during first fortnight of June. Disease tolerance of varying degree was observed under natural conditions in the available potato germplasm. Cultivar SM/92-338 proved tolerant to A. solani while as, cultivars Kufri himami, SM/96-127 and SM/94-44 showed moderate tolerance to the disease compared to rest of the 21 test cultivars. Evaluation of bioagents revealed that all the test bioagents were significantly effective in inhibiting the mycelial growth of A. solani under dual culture method. Trichoderma harzianm exhibited maximum mycelial growth inhibition of 71.85 per cent followed by T. viride (65.93%) and Trichoderma virens (58.65%). Evaluation of plant extracts revealed that all the test extracts were significantly superior in inhibiting the mycelial growth of A. solani at various test concentrations. Datura stramonium exhibited maximum mycelial growth inhibition of 61.12 per cent followed by Artimesia absinthium (58.54%), Juglans regia (38.31%), Mentha spicata (38.02%) and Uretica dioica (37.34%). Systemic fungitoxicants and non-systemics were tested in vitro for mycelial growth inhibition at (100-350 ppm and 1000-3500 ppm, respectively). Among the systemic fungitoxicants hexaconazole (0.03 %) followed by fenconazole (0.03%) proved significantly superior at all tested concentration, whileas mancozeb (0.2%) followed by propineb (0.2%) proved significantly superior in inhibiting mycelial growth the individual and combined effect of most effective in vitro fungitoxicant, bioagent and botanicals was also evaluated for the management of potato early blight in field. Among various treatment combinations seed treatment with mencozeb (0.2%) + foliar spray with hexaconazole (0.03%) + foliar spray with datura (50%) + foliar spray with T. harzianum (1 x 107 spores ml-1) proved significantly superior
Studies on Leaf Spot Disease of Strawberry in Kashmir.
No full textAn extensive survey conducted in district Srinagar of Kashmir Valley during the two years of 2005 and 2006 revealed prevalence of leaf spot disease in strawberry. Mean disease incidence and intensity of 40.42 and 23.96 per cent were recorded in the year 2005 and that of 42.06 and 25.17 per cent during the year 2006 respectively. The disease was comparatively more severe during the crop season 2006 in comparison to that of 2005. The disease was characterised by the appearance of small, round to oval spots with light coloured centres measuring approximately 0.5 mm in size, which on coalescing formed irregular patches on leaves, ultimately resulting in complete blighting of leaves. The causal fungus was identified as Hainesia lythri. Maximum radial mycelial growth and excellent pycnidial formation were recorded on potato dextrose agar and malt extract agar media at temperatures 20 and 25 (±1oC) and pH of 7.0 and 6.5 under in vitro conditions. The pathogen perpetuated throughout winter on diseased leaves left on the soil surface, in the form of pycnidia. The number of fruiting bodies, spores cm-2 leaf area and the viability of spores decreased with the increase in depth of placement in soil. The maximum fruiting bodies and spores cm-2 leaf area on overwintered leaves were observed during 1st to 2nd fortnight of March. The infected overwintered leaves lying on the ground surface of the field serve as the most important overwintering site for H. lythri. Disease tolerance of varying degree has been observed under natural conditions in the available strawberry germplasm. Blackmore and Brighton showed somewhat tolerance to the disease compared to other varieties. Among cultural practices tested, plants maintained at 45 cm spacing with weeding + older leaves removed proved superior in both the years followed by plants maintained with weeding and older leaves removed in checking the disease. Evaluation of plant extracts revealed that all the test extracts were significantly effective in inhibiting the mycelial growth of H. lythri at various test concentrations. Allium sativum has exhibited the maximum mycelial growth inhibition of 62.08 per cent followed by Lavendula officinalis (60.52%) and Datura stramonium (60.19%). In vivo conditions, Allium sativum at 40 and 50 per cent concentration proved significantly superior in checking the disease followed by Lavendulla officinalis and Datura stramonium. Systemic fungitoxicants, in general and Ergosterol Biosynthesis Inhibitors (ESBI’s) in particular proved significantly superior over non-systemic fungitoxicants both in vitro and in vivo. Among the systemic fungitoxicants hexaconazole followed by carbendazim proved superior over non-systemic fungitoxicants in inhibiting the mycelial growth. Field experimentation on fungicidal efficacy also yielded the superiority of systemic fungitoxicants over non-systemic fungitoxicants ones
Studies on Blight of Carnation (Dianthus caryophyllus L.) in Kashmir Valley
No full textAn extensive survey conducted in two major cut flower growing districts viz. Srinagar and Anantnag of Kashmir Valley during the two years 2003 and 2004 revealed prevalence of blight of carnation in both the districts. Mean disease incidence of 19.65 per cent was recorded in the year 2003 in comparison to 27.13 per cent during the year 2004 in standard type carnation, whereas, the mean disease incidence of 21.94 and 29.25 per cent during the year 2003 and 2004 respectively, in spray type carnation. The disease incidence and intensity was comparatively higher in garden followed by lawns and nursery. The disease was characterized by the appearance of small, circular, translucent to light brown lesions with yellow halo measuring approximately 0.1 mm in size which on coalescing formed irregular necrotic patches on leaves, ultimately resulting in complete blighting of leaves and premature death of plant. Under severe condition lesion were noticed on stem and flower of carnation plant. The causal fungus was identified as Alternaria dianthi. Maximum conidial germination was recorded at a temperature 25 0C, relative humidity of 96.1 per cent and pH of 5.5 to 7.0 under in vitro conditions. The pathogen perpetuated throughout winter on diseased leaves left on the soil surface, in the form of mycelium and conidia. The conidia formation and their viability decreased with the depth of their placement of infected leaves in soil. The maximum conidial production on overwintered leaves was observed during 1st to 2nd fortnight of May. The infected overwintered leaves lying on the ground surface of the field serve as the most important overwintering site for A. dianthi. The fungitoxicants tested for their efficacy against the spore germination and their field evaluation against the disease proved significantly effective as compared to check. Systemic fungitoxicants, in general and Ergosterol Biosynthesis inhibitors (ESBI’s) in particular proved significantly superior over non systemic fungitoxicants both in vitro and in vivo. Among the systemic fungitoxicants penconazole followed by hexaconazole proved superior over others in inhibiting 50 per cent conidial germination at a concentration of 100 µg/ml. Among non–systemic fungitoxicants mancozeb followed by captan proved superior at 1500 µg/ml in inhibiting more than 95 per cent conidial germination. Field experimentation on fungicidal efficacy also yielded the superiority of systemic fungitoxicants over non-systemic fungitoxicants ones. Among the five biocontrol agent tested, Trichoderma harzianum and T. viride were found highly antagonistic to A. dianthi in dual culture as well as their cultural filtrates significantly reduced the mycelial growth and spore germination of the pathogen. Adoption of pinching and a single spray of fungitoxicants in May gave best disease control of 39.2–59.9 per cent. In integration of fungicide/ biocontrol agent spray with cultural practices, a combination of treatment comprising of mancozeb along with plucking of diseased leaves and pinching proved significantly superior for the management of blight of carnation. Disease tolerance of varying degree have been observed under natural condition in the available carnation germplasm. The Tempo showed somewhat tolerance to the disease compared to other varieties. However this needs further investigation so as to develop resistant cultivar against the disease
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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