1,720,965 research outputs found
Genetic variability for root and shoot traits in a lentil (Lens culinaris Medik.) recombinant inbred line population and their association with drought tolerance
No full textLentil (Lens culinaris Medik.) is usually grown under rainfed environments and often encounters drought stress from limited rainfall. Little information is available about shoot and root traits in association with drought tolerance. We studied variability for root and shoot traits related to drought tolerance using an F6–8 population of 133 recombinant inbred lines (RILs) from the cross ILL6002 × ILL5888. We found important variation between genotypes and also high variation in heritability values for root and shoot traits at 38 days after sowing the parents and RILs under both well-watered and drought-stressed treatments during two consecutive seasons in the greenhouse. The higher heritability values were obtained under drought stress treatment and suggest that selection in water-limited environments would be more effective in achieving genetic gains. Drought had reduced trait values, except root–shoot ratio that was likely to be enhanced underlying the importance of this trait for drought tolerance. The quantitative and continuous distributions of variation are the evidence for polygenic control of these traits and the possibility of mapping the quantitative trait loci (QTL). Statistically significant associations between root and shoot traits such as dry shoot biomass and chlorophyll content were noted, highlighting the reliability of indirect selection for underground traits (root) based on these aboveground traits in breeding programs. Significant correlations and regressions were demonstrated between dry root biomass, lateral root number, root surface area, dry shoot biomass, root–shoot ratio, chlorophyll content and drought tolerance as estimated by wilting severity from limited water supply. This shows the importance of a well-developed root system and early biomass development for drought tolerance. Identification and mapping of QTL related to studied traits in this population would be a first step for starting marker-assisted selection
Registration Of 'Chakkouf' Lentil In Morocco
No full textLentil (Lens culinaris Medikus subsp. culinaris) is one of the oldest food legumes and is the third most important one in Morocco. It provides a valuable and balanced protein source in the human diet and plays an important role in cropping systems because of its ability to fix nitrogen. The productivity of the crop suffers because of numerous biotic and abiotic factors. High-yielding cultivars with improved characteristics are needed to increase lentil production and profitability. 'Chakkouf' (Reg. No. CV-34, PI 663991) lentil was developed using both modified pedigree and bulk methods by the Institut National de la Recherche Agronomique, Morocco in collaboration with the International Center for Agricultural Research in the Dry Areas. Tested as ILL 6001-81, Chakkouf was approved for release in 2009 by the Office National de Securite Sanitaire des Produits Alimentaires, Morocco. Chakkouf is a selection from an advanced F-6 line, FLIP 86-15L, which was derived from a cross of 'Precoz' (ILL 4605; PI 515969) with 'Laird' (ILL 4349; PI 471916). Chakkouf is an early-flowering (similar to 88 d), early-maturing (similar to 139 d), and high-yielding (similar to 40% over the local check variety 'L24') lentil cultivar with high zinc (62 mg kg(-1)) and iron (76.7 mg kg(-1)) in the seeds. Chakkouf showed good agronomic performance under drought conditions and wide adaptation for the Moroccan semiarid environments. Chakkouf showed field resistance for rust [caused by Uromyces viciae-fabae (Pers.) J. Schrot] and Ascochyta blight (caused by Ascochyta fabae Speg. f. sp. lentis) during the years of evaluation in replicated yield trials in all experimental stations. Chakkouf offers the producer an economic advantage in cropping systems where it is planted as a rainfed crop in moisture-deficient soils, usually in rotation with cereals
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
Comparaison de lignées avancées de lentille sous stress hydrique durant la phase de floraison et formation des gousses
No full textLentil (Lens culinaris Medikus Subsp. culinaris) is grown as a rain-fed crop in Morocco mainly in moisture- deficient soils. Drought tolerance as well as high and stable seed yield are among the important traits of lentil cultivars preferred by Moroccan farmers. In order to determine terminal drought tolerance of some advanced lentil genotypes, an experiment was conducted in a greenhouse. The lines were planted in plastic pots (20 cm diameter and 40 cm height) in a randomized complete block with four replications and two treatments: well watered (applied 600 ml of water, three times per week) and water stressed condition (applied 180 ml of water, once a week). The results revealed that, for all the genotypes tested, drought stress reduced seed yield, seed weight, harvest index, total biomass and pod filling period by accelerating the maturity. Among the genotypes tested, the genotype F87-9 was the most susceptible. On the other hand the genotype F2003-7 was the most drought tolerant genotype because of its short cycle, a long pod filling period and less affected by water stress. This genotype was also characterized by a high harvest index, well developed root architecture (higher number of lateral roots and root length) and the capacity to maintain high leaf relative water content. Two other genotypes namely F00-24 and L8PS05-5-7 showed moderate level of drought tolerance characteristics. The susceptible genotype F87-9 had the lowest leaf relative water content
Chickpea genetic improvement in Morocco: State of the art, progress and prospects
Get PDFoai:ojs.pkp.sfu.ca:article/815Chickpea is the second major food legume in Morocco. Compared to spring type, winter type is more adapted to semi-arid rainfed areas, escaping the frequent end-cycle drought and heat stresses. The winter chickpea breeding program of INRA Morocco aims to develop and release varieties that are well adapted to different agro-ecological areas, with high yield potential, resistant to Ascochyta blight and others diseases and pests prevalent in the target areas. Tolerance to drought and ability for mechanized harvesting are also other important objectives. Other traits, related to seed quality, such as large seed size, cooking time and high nutritional value, are also being introduced in the breeding program. Since 1994, seven winter chickpea varieties were released and registered by the breeding program. Those new high yielding varieties are resistant to Aschochyta blight. However, seed increase and marketing are still needed to make these varieties available to farmers.
Keywords: chickpea, genetic improvement, varieties, Morocc
Genetic diversity analysis of Moroccan lentil (Lens culinaris Medik.) landraces using Simple Sequence Repeat and Amplified Fragment Length Polymorphisms reveals functional adaptation towards agro‐environmental origins
No full textIn the absence of previous molecular characterization, we assessed genetic diversity of 53 Moroccan lentil landraces including two local cultivars using simple sequence repeat (SSR) and amplified fragment length polymorphisms (AFLP). Nineteen SSRs yielded 213 alleles, and seven AFLP primer combinations gave 766 fragments of which 422 were polymorphic. Moderate to high genetic variation was observed. Several small groups of landraces were differentiated. Interestingly, one of the smallest groups contained short‐cycle landraces with high early vegetative growth. Landraces in that group were from the dry land location of Abda, where they were likely selected for adaptation to drought and heat stress over centuries. Another group contained two landraces from highland areas that may have been selected for specific adaptation to cold stress. A third group contained one landrace from the Zear region known for its seed quality and has been proposed for the protected designation of origin (PDO) quality mark. Both techniques gave evidence of differentiation of the latter landrace supporting the idea of PDO attribution. Functional grouping according to agro‐environmental origins, cycle duration and early vegetative vigour was observed
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
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