Academic literature on the topic 'Varietal trait improvements'
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Journal articles on the topic "Varietal trait improvements"
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Richards, Richard A., Greg J. Rebetzke, Michelle Watt, A. G. (Tony) Condon, Wolfgang Spielmeyer, and Rudy Dolferus. "Breeding for improved water productivity in temperate cereals: phenotyping, quantitative trait loci, markers and the selection environment." Functional Plant Biology 37, no. 2 (2010): 85. http://dx.doi.org/10.1071/fp09219.
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Consistent gains in grain yield in dry environments have been made by empirical breeding although there is disturbing evidence that these gains may have slowed. There are few examples where an understanding of the physiology and the genetics of putative important drought-related traits has led to improved yields. Success will first depend on identifying the most important traits in the target regions. It will then depend on accurate and fast phenotyping, which, in turn, will lead to: (1) trait-based selection being immediately transferable into breeding operations and (2) being able to identify the underlying genes or the important genomic regions (quantitative trait loci), perhaps leading to efficient marker-based selection (MBS). Genetic complexity, extent of genotype × environment (G × E) interaction and sampling cost per line will determine value of phenotyping over MBS methods. Here, we review traits of importance in dry environments and review whether molecular or phenotypic selection methods are likely to be the most effective in crop improvement programs and where the main bottlenecks to selection are. We also consider whether selection for these traits should be made in dry environments or environments where there is no soil water limitation. The development of lines/populations for trait validation studies and for varietal development is also described. We firstly conclude that despite the spectacular improvements in molecular technologies, fast and accurate phenotyping remains the major bottleneck to enhancing yield gains in water-limited environments. Secondly, for most traits of importance in dry environments, selection is generally conducted most effectively in favourable moisture environments.
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Maligalig, Rio, Matty Demont, Wendy J. Umberger, and Alexandra Peralta. "Understanding Filipino Rice Farmer Preference Heterogeneity for Varietal Trait Improvements: A Latent Class Analysis." Journal of Agricultural Economics 72, no. 1 (July 14, 2020): 134–57. http://dx.doi.org/10.1111/1477-9552.12392.
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Kabir, M. S., MU Salam, AKMS Islam, M. A. R. Sarkar, MAA Mamun, MC Rahman, B. Nessa, et al. "Doubling Rice Productivity in Bangladesh: A Way to Achieving SDG 2 and Moving Forward." Bangladesh Rice Journal 24, no. 2 (May 14, 2021): 1–47. http://dx.doi.org/10.3329/brj.v24i2.53447.
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Built on deep-rooted political and cultural heritage, ‘rice security’ is the foundation of ‘food security’ in Bangladesh. The country has been in production-surplus of rice in the current decade feeding over 165 million people. This on-going ‘selfsufficiency momentum’ would require to maintain to meet increased demand from growing future population. On developmental side, Bangladesh is placed among the three of the world’s fastest growing economies in the years through to 2050. Rice sector would need to match with the pace of this growth. In addition, agriculture sector, that includes rice, is to double the productivity as the government commits to meet the SDG goal 2.3.1. This study addresses those issues through scoping increased rice production and productivity in Bangladesh, developing a plan of work (POW) on translating the scope and designing implementation plans and actions, incorporating efficiency, resilience, stability and sustainability issues, to achieve the POW. The study has used brainstorming, and rigorous analysis to achieve the objectives. The productivity has been explained in terms of yield- and labour-productivity. The developed three-winged ‘doubling rice productivity (DRP)’ framework directs yield enhancement and production accumulation in unexplored spaces (Wing-1); increased adoption of mechanization to impact on labour productivity (Wing-2), and improvements in nutritional quality and rice-based product diversity, and stabilizing the farmgate price (Wing-3). Analyses show, from the baseline figure of 35.29 MT in 2015, rice production in the country can be raised to 46.90 MT in 2030, 54.09 MT in 2040 and 60.85 MT in 2050 with combined contributions of three pillars – yield improvements by enhanced varietal potential (Pillar 1), reduction in existing yield gap (Pillar 2) and production increase by exploring unexplored spaces for rice (Pillar 3) of Wing-1 of the DRP. This production will produce a surplus of 6.50, 10.29 and 13.65 MT in 2030, 2040 and 2050, respectively, over the production target (40.40, 43.80 and 47.20 MT in 2030 and 2050, respectively). Results further reveal that through scale-appropriate mechanization backed up by estimated fair price, labour productivity in rice will be doubled by 2029, meeting the SDG 2.3.1. Good number of released varieties have been identified to have specific nutritional trait, and value adding quality. We have emphasized on much needed actions on demand-driven research for varietal development and field-adoptable management, mechanization for transplanting and harvesting operations, accommodation of rice in unexplored spaces, farmer-based speedy seed multiplication and dissemination system, establishment of commission for agricultural costs and prices, input buffer stock terminals for managing production risk, long-term storage and export of surplus production, and research-publicity-market development for rice-based products through public-private partnership. It is concluded that efficiency, resilience and sustainability around the three wings of DRP in the rice production systems to be ensured to achieve the rice production, productivity and labour use estimates. Bangladesh Rice J. 24 (2): 1-47, 2021
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Smith, A. B., B. R. Cullis, R. Appels, A. W. Campbell, G. B. Cornish, D. Martin, and H. M. Allen. "The statistical analysis of quality traits in plant improvement programs with application to the mapping of milling yield in wheat." Australian Journal of Agricultural Research 52, no. 12 (2001): 1207. http://dx.doi.org/10.1071/ar01058.
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It is well known that the response to selection for grain yield is improved with the use of appropriate experimental designs and statistical analyses. The issues are more complex for quality traits since the data are obtained from a 2-phase process in which samples are collected from the field then processed in the laboratory. This paper presents a method of analysis for quality trait data that allows for variation arising from both the field and laboratory phases. Initially, an analysis suitable for standard varietal selection is presented. This is extended to include molecular genetic marker information for the purpose of detecting quantitative trait loci. The technique is illustrated using two doubled haploid wheat (Triticum aestivum L.) populations in which the trait of interest is milling yield.
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Zhao, Yawei, Haiyan Deng, Ruifa Hu, and Changzhao Xiong. "Impact of Government Policies on Seed Innovation in China." Agronomy 12, no. 4 (April 12, 2022): 917. http://dx.doi.org/10.3390/agronomy12040917.
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Seed innovation is of great importance for more sustainable agriculture and food systems. Using data on nationally approved rice varieties and farmers’ adopted varieties, this study examined rice varietal trait changes in China over the past four decades and explored the impact of national crop varietal approval policies on approved rice traits as well as the effect of seed subsidies on adopted rice trait changes. The results showed that the yield of approved varieties and adopted varieties showed an upward trend over the past decades, and the yield of approved varieties was slightly higher than that of adopted varieties in most years. The rice quality of approved rice varieties showed a trend of continuous improvement but the adopted varieties showed a downward trend. The disease resistance of the approved varieties failed to show an increasing trend overall while the adopted varieties remained unchanged. National crop variety approval policies seemed to exert a significant positive impact on approved rice yield traits but exert a negative influence on disease resistance. Subsidies for superior seed varieties significantly increased adopted rice quality but decreased yield. The results suggest that national crop variety approval policies are the gatekeeper of improved rice, so the government can improve the policies to more meet farmers’ and consumers’ needs.
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BHAT, Zahoor Ahmad, Wasakha Singh DHILLON, Rizwan RASHID, Javid Ahmad BHAT, Waseem Ali DAR, and Mohammad Yousf GANAIE. "The role of Molecular Markers in Improvement of Fruit Crops." Notulae Scientia Biologicae 2, no. 2 (June 13, 2010): 22–30. http://dx.doi.org/10.15835/nsb224222.
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Markers have been used over the years for the classification of plants. Markers are any trait of an organism that can be identified with confidence and relative easy, and can be followed in a mapping population on another hand markers be defined as heritable entities associated with the economically important trait under the control of polygenes. Morphological markers can be detected with naked eye (naked eye polymorphism) or as difference in physical or chemical properties of the macromolecules. In other words, there are two types of genetic markers viz. morphological markers or naked eye polymorphism and non-morphological markers or molecular markers. Morphological markers include traits such as plant height, disease response, photoperiod, sensitivity, shape or colour of flowers, fruits or seeds etc. Molecular markers include biochemical constituents. Morphological markers have many limitations for being used as markers particularly in fruit crops because of long generation time and large size of fruit trees besides being influenced by environment. Consequently, molecular markers could be appropriate choice to study and preserve the diversity in any germplasm. Molecular markers have diverse applications in fruit crop improvement, particularly in the areas of genetic diversity and varietal identification studies, gene tagging, disease diagnostics, pedigree analysis, hybrid detection, sex differentiation and marker assisted selection.
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SAMITA, S., M. ANPUTHAS, and D. S. de Z. ABEYSIRIWARDENA. "ACCOUNTING FOR MULTI TRAITS IN RECOMMENDING RICE VARIETIES FOR DIVERSE ENVIRONMENTS." Experimental Agriculture 41, no. 2 (April 2005): 213–25. http://dx.doi.org/10.1017/s0014479704002509.
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Recommendations of crop varieties are usually done on the basis of grain yield. However, there are other important traits related to quality and agronomy that need to be considered. This study has clearly shown that grain yield is often not related to some important traits of the crop. Under such circumstances, selection based on yield can lead to the loss of these important characters. Recent research has also indicated the need for a multi-trait approach to recommending crop varieties. However, such approaches, as suggested in the literature, are subjective and do not have a sufficient statistical basis. This study proposes a methodology for varietal recommendations by taking account of all important traits. It is a multivariate approach considered to be an improvement on the univariate method previously proposed. Data from rice varieties of 3, 3½ and 4½ month maturity groups, cultivated across diverse environments, over two seasons in Sri Lanka were used to illustrate the proposed methodology. The results suggest that the new method will be appropriate for taking in to account all important traits along with yield.
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RK, Shadmanov. "Biotechnology of Accelerated Breeding and Improvement of Cotton Varieties." Biotechnology of Accelerated Breeding and Improvement of Cotton Varieties 1, no. 1 (December 20, 2018): 1–6. http://dx.doi.org/10.24966/brb-0019/100001.
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The success of any breeding program depends upon the availability of genetic variability of traits of interest and availability of efficient markers for selection of traits. Within the last 20 years, molecular biology has revolutionized conventional breeding techniques in all areas. Biochemical and molecular techniques have shortened the duration of breeding programmes. In this article are discussed the opportunities of use of biochemical markers (enzymes and proteins) for acceleration of breeding of new and improving of existing cotton varieties on tolerance to different unfavourable environmental factors and with complex of desired traits and varietal purity. We analyzed nineteen (19) local cotton varieties and lines (Gossypium hirsutum L.) for this purpose. The indices of oxidoreductases class enzymes and two phosphoprotein markers were developed as objective biochemical markers of earliness, homogeneity, tolerance to Verticillium wilt, drought and salinity.
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Neale, David B., and Claire G. Williams. "Restriction fragment length polymorphism mapping in conifers and applications to forest genetics and tree improvement." Canadian Journal of Forest Research 21, no. 5 (May 1, 1991): 545–54. http://dx.doi.org/10.1139/x91-076.
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It is now technically possible to construct high-density restriction fragment length polymorphism maps for almost any conifer. Hundreds of new genetic markers will become available for forest genetics research and tree-improvement applications. Having a large number of genetic markers will improve efficiency in studies in which isozymes or other markers have traditionally been applied (e.g., genetic variation in populations, paternity analysis, varietal identification, and seed-orchard efficiency). High-density restriction fragment length polymorphism maps may make it possible to (i) identify quantitative trait loci and (ii) practice marker-assisted selection in conifer breeding.
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Pembleton, L. W., J. Wang, N. O. I. Cogan, J. E. Pryce, G. Ye, C. K. Bandaranayake, M. L. Hand, et al. "Candidate gene-based association genetics analysis of herbage quality traits in perennial ryegrass (Lolium perenne L.)." Crop and Pasture Science 64, no. 3 (2013): 244. http://dx.doi.org/10.1071/cp12392.
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Due to the complex genetic architecture of perennial ryegrass, based on an obligate outbreeding reproductive habit, association-mapping approaches to genetic dissection offer the potential for effective identification of genetic marker–trait linkages. Associations with genes for agronomic characters, such as components of herbage nutritive quality, may then be utilised for accelerated cultivar improvement using advanced molecular breeding practices. The objective of the present study was to evaluate the presence of such associations for a broad range of candidate genes involved in pathways of cell wall biosynthesis and carbohydrate metabolism. An association-mapping panel composed from a broad range of non-domesticated and varietal sources was assembled and assessed for genome-wide sequence polymorphism. Removal of significant population structure obtained a diverse meta-population (220 genotypes) suitable for association studies. The meta-population was established with replication as a spaced-plant field trial. All plants were genotyped with a cohort of candidate gene-derived single nucleotide polymorphism (SNP) markers. Herbage samples were harvested at both vegetative and reproductive stages and were measured for a range of herbage quality traits using near infrared reflectance spectroscopy. Significant associations were identified for ~50% of the genes, accounting for small but significant components of phenotypic variance. The identities of genes with associated SNPs were largely consistent with detailed knowledge of ryegrass biology, and they are interpreted in terms of known biochemical and physiological processes. Magnitudes of effect of observed marker–trait gene association were small, indicating that future activities should focus on genome-wide association studies in order to identify the majority of causal mutations for complex traits such as forage quality.
Dissertations / Theses on the topic "Varietal trait improvements"
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Maligalig, Rio Lawas. "Eliciting farmer preferences for rice varietal trait improvements using an experimental methodology based on investment games." Thesis, 2018. http://hdl.handle.net/2440/113577.
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Rice value chains are changing rapidly in Asia, partly due to changing consumption patterns, and also as a result of increasingly stringent quality standards imposed on producers. Rice farmers and other value chain actors must now consider rice varieties that are suitable for unique production environments and processing scenarios. Rice breeders face similar trade-offs, as demand for their products (genetics or new varieties of rice) is derived from farmers’ and other value chain actors’ (including consumers’) demand for rice varieties and traits. Ultimately, breeders need to make informed decisions about where to invest and how to allocate increasingly scarce research and development resources. To facilitate successful adoption, it is important that farmers’ preferences and needs are incorporated in the early phases of breeding research to make sure that rice varieties developed are suitable to local conditions and at the same time respond to market requirements.
This thesis utilises an innovative experimental Investment Game Application (IGA), which is a newly developed application for eliciting preferences for rice variety traits. The game is designed to simulate an investment market in which farmers can participate in investment decisions for public rice breeding programs. In the IGA, farmers are asked to identify a replacement variety and the traits of this variety that they want to see improved. Farmers are provided with an endowment fund, which they are asked to use to invest in trait improvements.
Therefore, using data from the investment games conducted in February 2016 in Nueva Ecija, Philippines, this thesis analyses farmer preferences for rice varietal trait improvements (VTIs). A total of 122 rice-farming households participated in the experiment, with both the husband and wife taking part in activities. The thesis consists of three core chapters, which specifically analyse the following: (i) farmers’ investment preferences for VTIs and the factors that influence these preferences; (ii) farmers’ heterogeneity in preferences for VTIs using a latent class cluster analysis; and (iii) gender and intrahousehold dynamics in the decision-making process regarding investment in VTIs.
The results from the analysis of farmers’ investment preferences suggest that Filipino farmers prioritize investment in stress tolerance traits such as lodging tolerance, and disease and insect resistance. This is perhaps not surprising, because, on average, the replacement variety selected for improvement is already accepted in the market, i.e. it has the grain quality traits that Filipino consumers prefer (long and slender). On the other hand, the factors that influence farmers’ decisions to invest in VTIs are related to the cropping season, variety type, and access to land.
Filipino rice farmers have significant heterogeneity in investment preferences; with a latent class cluster analysis identifying four distinct farmer segments each with unique preferences for the VTIs. When gender and intrahousehold dynamics in preferences are accounted for in the analysis, results suggest that the replacement variety selected individually and jointly by the couples is the same for most of the household-respondents. Moreover, the wife has more influence on the household’s choice of VTIs when she works on-farm, and/or when she is considering the impact of VTI investment decisions on the household’s future wellbeing. The results of the study can guide breeders and donors to develop more resource efficient and client-oriented rice-breeding programs. Moreover, the novel approach of the methodology can transform the way farmer preferences for variety traits are elicited and can provide an opportunity for farmers to be truly involved in the agricultural research process through participation in resource allocation and priority-setting activities.Thesis (Ph.D.) (Research by Publication) -- University of Adelaide, Centre for Global Food and Resources, 2018
Books on the topic "Varietal trait improvements"
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Meddings, Jennifer, Vineet Chopra, and Sanjay Saint. Preventing Hospital Infections. 2nd ed. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780197509159.001.0001.
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This book provides a detailed, step-by-step description of a model quality improvement intervention for hospitals, pinpointing the obstacles and showing how to surmount them. This second edition has been carefully updated, with new material describing some technical aspects of infection prevention, new tools for use by front-line providers, and results of recent large collaborative infection prevention studies. In easy-to-read, user-friendly language, it explains why clinicians neglect or actively oppose quality changes—from physicians who distrust change, to nurses who want to protect their turf, to infection preventionists who avoid the wards. The book also sheds light on how and why hospitals embark on quality improvements, the role of the hospital’s leadership cadre, the selection and training of the project team, and how to sustain quality gains long term. The intervention framework described in the book focuses on the prevention of hospital-associated infections—in particular, catheter-associated urinary tract infection (CAUTI)—but it is directly applicable to a variety of other hospital issues, such as falls, pressure sores, and Clostridioides difficile infection (CDI). In fact, the book includes a chapter applying this framework to a CDI prevention initiative. In addition, for hospitals having trouble with staff adherence to a quality initiative, we provide three infection-specific questionnaires (for CAUTI, CLABSI, and CDI) to help pinpoint individual problems, and provide a link to a website offering advice tailored to their specific circumstances.
Book chapters on the topic "Varietal trait improvements"
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Sukumaran, Sivakumar, Greg Rebetzke, Ian Mackay, Alison R. Bentley, and Matthew P. Reynolds. "Pre-breeding Strategies." In Wheat Improvement, 451–69. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-90673-3_25.
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AbstractIn general terms, pre-breeding links needed traits to new varieties and encompasses activities from discovery research, exploration of gene banks, phenomics, genomics and breeding. How does pre-breeding given its importance differ from varietal-based breeding? Why is pre-breeding important? Pre-breeding identifies trait or trait combinations to help boost yield, protect it from biotic or abiotic stress, and enhance nutritional or quality characteristics of grain. Sources of new traits/alleles are typically found in germplasm banks, and include the following categories of ‘exotic’ material: obsolete varieties, landraces, products of interspecific hybridization within the Triticeae such as chromosome translocation lines, primary synthetic genotypes and their derivatives, and related species mainly from the primary or secondary gene pools (Genus: Triticum and Aegilops). Genetic and/or phenotyping tools are used to incorporate novel alleles/traits into elite varieties. While pre-breeding is mainly associated with use of exotics, unconventional crosses or selection methodologies aimed to accumulate novel combinations of alleles or traits into good genetic backgrounds may also be considered pre-breeding. In the current chapter, we focus on pre-breeding involving research-based screening of genetic resources, strategic crossing to combine complementary traits/alleles and progeny selection using phenomic and genomic selection, aiming to bring new functional diversity into use for development of elite cultivars.
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Calayugan, Mark Ian C., B. P. Mallikarjuna Swamy, Chau Thanh Nha, Alvin D. Palanog, Partha S. Biswas, Gwen Iris Descalsota-Empleo, Yin Myat Myat Min, and Mary Ann Inabangan-Asilo. "Zinc-Biofortified Rice: A Sustainable Food-Based Product for Fighting Zinc Malnutrition." In Rice Improvement, 449–70. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-66530-2_13.
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AbstractThe lack of dietary diversity among poor communities has led to nutritional consequences, particularly zinc deficiency. An adequate intake of mineral- and vitamin-rich food is necessary for achieving and maintaining good health. Zinc is one of the micronutrients considered essential to improve human health and decrease the risk of malnutrition. Biofortification of rice through breeding is a cost-effective and sustainable strategy to solve micronutrient malnutrition. The Biofortification Priority Index prepared by HarvestPlus clearly identified several countries in Asia with an immediate need for Zn biofortification. The International Rice Research Institute (IRRI) and its national partners in target countries are making efforts to develop Zn-biofortified rice varieties. The first set of high-Zn rice varieties has been released for commercial cultivation in Bangladesh, India, the Philippines, and Indonesia. Efforts have begun to mainstream grain Zn to ensure that the Zn trait becomes an integral part of future varieties. Huge scope exists to apply advanced genomics technologies such as genomic selection and genome editing to speed up high-Zn varietal development. An efficient rice value chain for Zn-biofortified varieties, quality control, and promotion are essential for successful adoption and consumption. The development of next-generation high-Zn rice varieties with higher grain-Zn content, stacking of multiple nutrients, along with good grain quality and acceptable agronomic traits has to be fast-tracked. Healthier rice has a large demand from all stakeholders, so we need to keep up the pace of developing nutritious rice to meet the demand and to achieve nutritional security.
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Guzmán, Carlos, Maria Itria Ibba, Juan B. Álvarez, Mike Sissons, and Craig Morris. "Wheat Quality." In Wheat Improvement, 177–93. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-90673-3_11.
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AbstractWheat quality is a complex concept whose importance lies in determining the ability of each segment of the post-harvest processing and marketing industries to minimize cost while maximizing profit. Wheat quality is also a highly subjective concept that could be defined differently by the various stakeholders in the wheat value chain. It is usually subdivided into milling, processing, end-use and nutritional quality. Of these subcomponents, end-use quality, the ability of a wheat variety to produce a specific food according to the consumers preferences is probably the most important. Wheat is used to make hundreds of different products worldwide, each one with specific grain quality requirements. In this chapter are explained the main traits that define end-use quality (grain hardness, gluten, color and starch) and that need to be modulated to obtain the desired product properties. The genetic control as well as the environmental effects on those traits are also presented. Finally, breeding and selection strategies to genetically improve end-use quality for the most important wheat products globally (bread, noodles, cookies, and pasta) are presented in brief.
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Kushwah, Ashutosh, Shayla Bindra, Inderjit Singh, G. P. Dixit, Pankaj Sharma, S. Srinivasan, P. M. Gaur, and Sarvjeet Singh. "Advances in Chickpea Breeding and Genomics for Varietal Development and Trait Improvement in India." In Accelerated Plant Breeding, Volume 3, 31–66. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-47306-8_2.
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Majumdar, Snehalata, Falguni Barman, and Rita Kundu. "Genomic Approaches to Understand Varietal Differences in Rice Species and Genotypes with Respect to Stress Response and Quality Traits." In Rice Research for Quality Improvement: Genomics and Genetic Engineering, 159–99. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-4120-9_7.
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Gatica-Arias, Andrés, Jorge Rodríguez-Matamoros, Ana Abdelnour-Esquivel, and Marta Valdez-Melara. "Determination of the optimal conditions for mutagenesis induction in a commercial Arabica coffee variety." In Mutation breeding, genetic diversity and crop adaptation to climate change, 326–37. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0034.
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Abstract Low genetic diversity and autogamous reproduction limit genetic improvement of Coffea arabica L. As a consequence, susceptibility to biotic and abiotic stresses increases. Induced mutagenesis is an alternative strategy for increasing genetic variability and for the development of varieties tolerant or resistant to biotic and abiotic factors. In the present study, the effect of three mutagenic agents (NaN3, EMS and 60Co gamma-rays) on survival of Arabica coffee zygotic embryos was evaluated. The zygotic embryos were immersed for 10 min in a solution of NaN3 (0, 2.5, 5.0, 7.5, 10.0, 12.5, 15.0 and 20.0 mM) or for 2 h in a solution of EMS (0, 0.5, 1, 1.5, 2, 4 and 6% v/v) or irradiated with 0, 20, 40, 60, 80 or 100 Gy. As the concentration or dose of the applied mutagen increased, survival decreased. The LD50 values for sodium azide, EMS and 60Co were 12.5 mM (51.6%), 1% v/v (48.3%) and 40 Gy (50.0%), respectively. Our results indicated that coffee zygotic embryos are suitable for chemical and physical mutagenesis and this offers an alternative for the genetic improvement of agriculturally important traits in coffee.
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Fladung, Matthias, Hely Häggman, and Suvi Sutela. "Application of RNAi technology in forest trees." In RNAi for plant improvement and protection, 54–71. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789248890.0007.
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Abstract A diverse set of small RNAs is involved in the regulation of genome organization and gene expression in plants. These regulatory sRNAs play a central role for RNA in evolution and ontogeny in complex organisms, including forest tree species, providers of indispensable ecosystem services. RNA interference is a process that inhibits gene expression by double-stranded RNA and thus causes the degradation of target messenger RNA molecules. Targeted gene silencing by RNAi has been utilized in various crop plants in order to enhance their characteristics. For forest tree species, most of the successful RNAi modification has been conducted in poplar. Over the past 20 years, successful RNAi-mediated suppression of gene expression has been achieved with a variety of economically important traits. Moreover, the stability of RNAi-mediated transgene suppression has been confirmed in field-grown poplars. In this chapter, we describe examples of successful RNAi applications mainly in poplar but also provide some information about application of RNAi in pest control in forest tree species. Advantages and disadvantages of this technology with respect to the particular features of forest tree species will be discussed.
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Fladung, Matthias, Hely Häggman, and Suvi Sutela. "Application of RNAi technology in forest trees." In RNAi for plant improvement and protection, 54–71. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789248890.0054.
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Abstract A diverse set of small RNAs is involved in the regulation of genome organization and gene expression in plants. These regulatory sRNAs play a central role for RNA in evolution and ontogeny in complex organisms, including forest tree species, providers of indispensable ecosystem services. RNA interference is a process that inhibits gene expression by double-stranded RNA and thus causes the degradation of target messenger RNA molecules. Targeted gene silencing by RNAi has been utilized in various crop plants in order to enhance their characteristics. For forest tree species, most of the successful RNAi modification has been conducted in poplar. Over the past 20 years, successful RNAi-mediated suppression of gene expression has been achieved with a variety of economically important traits. Moreover, the stability of RNAi-mediated transgene suppression has been confirmed in field-grown poplars. In this chapter, we describe examples of successful RNAi applications mainly in poplar but also provide some information about application of RNAi in pest control in forest tree species. Advantages and disadvantages of this technology with respect to the particular features of forest tree species will be discussed.
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Jegadeesan, Souframanien, and Kandali Sreenivasulu Reddy. "Radiation-induced mutations in genetic enhancement and development of new crop varieties in black gram (Vigna mungo (L.) Hepper)." In Mutation breeding, genetic diversity and crop adaptation to climate change, 303–11. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0031.
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Abstract Black gram (Vigna mungo (L.) Hepper), popularly known as urdbean or mash or black gram, is a grain legume rich in protein (25-28%), widely cultivated in the Indian subcontinent and to a lesser extent in Thailand, Australia and other Asian and South Pacific countries. Genetic improvement in this crop is hindered due to the narrow genetic base. As genetic variability is a prerequisite for any crop improvement programme, induced mutations provide an important source for generating variability. Radiation (gamma, X-rays and neutron) induced mutants were identified for various morphological and biochemical traits, creating a pool of genetic variability. These mutants were used in a cross-breeding programme to develop high-yielding, disease-resistant varieties in black gram. The effective blend of mutation and recombination breeding at the Bhabha Atomic Research Centre has resulted in the release of five black gram varieties (TAU-1, TAU-2, TPU-4, TU94-2 and TU-40) by incorporating desirable traits like large seed, wider adaptability, resistance to disease and improved quality. These varieties have been developed from mutants directly or by using them in cross-breeding programmes. For example, a black gram variety, N0.55, was irradiated with gamma-rays and electron beams to obtain a large number of mutants. The large-seed mutants, UM-196 and UM-201, were used in cross-breeding with the elite cultivar T-9 for developing the high-yielding varieties TAU-1, TAU-2, TPU-4, TU94-2 and TU-40. TAU-1 has become the most popular variety in Maharashtra state, occupying the maximum area under black gram cultivation. Induced mutations will continue to play an increasing role in generating genetic variability for various traits as a major component of environmentally sustainable agriculture.
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Tadele, Zerihun, Kebebew Assefa, Solomon Chanyalew, Abate Bekele, Annett Weichert, Mirjam Schnell, Nora Röckel, Negussu Hussein, and Gina Cannarozzi. "Application of mutation breeding to the improvement of the under-studied crop tef (Eragrostis tef (Zucc.) Trotter)." In Mutation breeding, genetic diversity and crop adaptation to climate change, 134–44. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0014.
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Abstract Induced mutation has been playing a significant role in the improvement of diverse crop types. This led to the release of over 3200 crop varieties in over 70 countries. We implemented induced mutation on tef (Eragrostis tef (Zucc.) Trotter), one of the most important cereal crops in the Horn of Africa, especially in Ethiopia, where it is annually cultivated on over 3 million hectares of land, equivalent to 30% of the total area allocated to cereals. Although tef is extensively cultivated in Ethiopia due to its resilience to diverse environmental stresses, the productivity of the crop is very low. The Tef Improvement Project based at the University of Bern in Switzerland employs mutation breeding to tackle major constraints in tef in order to enhance crop productivity. About 12,000 EMS (ethyl methanesulfonate) mutagenized M2 families were generated from four improved tef varieties, namely 'Tsedey', 'Dukem', 'Kora' and 'Dagim'. Screening for major traits of importance helped us to obtain several candidate lines, including semi-dwarf and lodging-tolerant, drought-tolerant and acid-soil-tolerant lines. Among these, the most promising ones were introgressed to locally adapted improved varieties followed by several years of testing at representative locations for traits of interest. As a result, a new variety called 'Tesfa' with a novel and desirable combination of traits was approved for release to the farming community. This shows that the project has been actively involved in all three phases of induced mutation: mutation induction, mutation detection and mutation breeding.
Conference papers on the topic "Varietal trait improvements"
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Albakay, Naji, Michael Hempel, and Hamid Sharif. "Novel Insights for Railroad Maintenance Using Big Data Analytics." In 2018 Joint Rail Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/jrc2018-6242.
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Train accidents can be attributed to human factors, equipment factors, track factors, signaling factors, and Miscellaneous factors. Not only have these accidents caused damages to railroad infrastructure and train equipment leading to excessive maintenance and repair costs, but some of these have also resulted in injuries and loss of lives. Big Data Analytics techniques can be utilized to provide insights into possible accident causes, thus resulting in improving railroad safety and reducing overall maintenance expenses as well as spotting trends and areas of operational improvements. We propose a comprehensive Big Data approach that provides novel insights into the causes of train accidents and find patterns that led to their occurrence. The approach utilizes a combination of Big Data algorithms to analyze a wide variety of data sources available to the railroads, and is being demonstrated using the FRA train accidents/incidents database to identify factors that highly contribute to accidents occurring over the past years. The most important contributing factors are then analyzed by means of association mining analysis to find relationships between the cause of accidents and other input variables. Applying our analysis approach to FRA accident report datasets we found that railroad accidents are correlating strongly with the track type, train type, and train area of operation. We utilize the proposed approach to identify patterns that would lead to occurrence of train accidents. The results obtained using the proposed algorithm are compatible with the ones obtained from manual descriptive analysis techniques.
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Pomrehn, Leonard P., and Panos Y. Papalambros. "Infeasibility and Non-Optimality Tests for Solution Space Reduction in Discrete Optimal Design." In ASME 1992 Design Technical Conferences. American Society of Mechanical Engineers, 1992. http://dx.doi.org/10.1115/detc1992-0133.
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Abstract Techniques to be employed for nonlinear design optimization with discrete variables are studied in the context of a particular problem arising from the design of a gear train. The mathematical model formulation was presented in an earlier article. In this sequel, a solution derivation is described, patterned as a multistage process. After certain reformulation and relaxation, a variety of infeasibility and non-optimality tests are performed, greatly reducing the size of the space containing the global optimum. Methods used to investigate the remaining space do not guarantee a global optimum, but could be replaced by more costly methods that do provide such guarantees. A global infimum is generated, bounding any improvements on the best known solution.
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Nakatsuka, Matthew Allan, Bryan K. Ghahremani, Phuong Dinh, Sumil Singh Thapa, Alexander Donovan Ventura, and Vinod Veedu. "Rapid Decarbonization Through Maximizing Gains from Process Improvements." In Offshore Technology Conference. OTC, 2022. http://dx.doi.org/10.4043/32123-ms.
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Abstract One of the biggest points of emphasis for the energy production industry is how to effectively decarbonize and reduce the footprint of generation activities while still maintaining sufficient capacity to fulfill the energy needs of the world at large. Unlike many other sectors that can pivot to alternate forms of zero-emission fuel, the very nature of fossil fuel extraction, production, and transmission makes this transition particularly difficult and expensive. Small, immediate gains in efficiency with minimal investment can play a significant role in both smoothing the energy transition as well as extending the window where climate effects and increases in global temperatures above 3.5°F can still be mitigated or eliminated. Previous work and field trials presented by the authors have demonstrated that efficiency losses associated with fouling of heat transfer surfaces are a significant contributor to carbon emissions; in steam generation plants, fouling of the main condenser can lead to increased backpressure and reductions in power output. Hard deposit buildup on the pre-heat train (PHT) of a refinery can result in dramatically increased fuel use to raise the temperature of production fluid so that is ready for separation and distillation. New materials capable of imparting low-surface energy properties and greatly reduced surface roughness have been demonstrated to significantly decrease fouling in many of these cases, opening untapped operational capacity. However, without careful monitoring of the exchanger itself, this capacity may go entirely unrealized and un-utilized. This paper presents a new strategy in developing a monitoring and prescriptive maintenance solution that can specifically work as a complement to determine improved heat transfer performance after refurbishment by an anti-fouling surface treatment. The thermal sensor intelligence module (TSIM) was designed to be a lightweight and self-contained system, with the ability to be easily deployed on heat transfer equipment. To make accurate and precise predictions for the absence or presence of fouling on a treated system, where both historical and real-time data may be limited, an ensemble learning method was utilized in conjunction with a subscale condenser system whereby the TSIM could be rapidly trained on a variety of simulated fouling conditions, and the presence or absence of treatment. The learning method demonstrated in this work allowed for the TSIM to improve its fouling predictions through a model that allows it to impute the values of different parameters if the deployed exchanger or condenser does not have the necessary instrumentation. This imputation and prediction of the missing exchanger parameters allows for the accuracy be improved by nearly 20%, and the precision and F1 scores to be comparable to the model with a full set of input features. Finally, results gathered from this test condenser system, and the calculation of heat transfer efficiency showed good correlation with previously reported field data gathered under similar conditions, with a roughly 3-7% improvement after the addition of the anti-fouling treatment.
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Katans, Edgars, and Irena Katane. "Evaluation of IT Companies as Learning Organizations from the Programmers’ Perspective." In 14th International Scientific Conference "Rural Environment. Education. Personality. (REEP)". Latvia University of Life Sciences and Technologies. Faculty of Engineering. Institute of Education and Home Economics, 2021. http://dx.doi.org/10.22616/reep.2021.14.011.
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The modern social science faces a new synergetic and social-ecological paradigm and the respective approaches in research activity. The synergetic approach allows for the investigation of a learning IT company as a “living” system, a synergic organization notable for its teamwork and team learning to ensure the introduction of innovations in the company and, along with that, a sustainable development and competitiveness of the company in a constantly changing environment. In its turn, the social-ecological approach allows a researcher to focus his attention on a continuous professional development of an individual programmer or a team of programmers by mutual cooperation and interaction with the whole IT company representing the environment of their professional activity and continuous learning. A learning organization has certain traits or indicators, which can be used for the evaluation of IT companies. The authors have developed a methodology for the evaluation of learning IT companies, which has been approved during the experimental research: a case study. 102 programmers working for various Latvian IT companies participated in the study. The aim of the study: to analyse the IT companies where the research participants work, evaluating them as learning organizations, as well as to assess the informational awareness and knowledge of the programmers about the continuous professional development and career growth possibilities at the respective companies. Among the 19 indicators (traits) of evaluation of a learning organization, the following three traits are the most typical ones for the IT companies where the research participants are working: (1) friendly atmosphere and mutual support within a company, cooperation when working as a team, sharing their knowledge, skills, competencies and experience while performing their work duties; (2) a company is trying to ensure its sustainable development and competitive ability; (3) self-education and continuous learning of a company to improve its activity and to diversify the variety of the target groups along with a continuous improvement of its products and services.
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DiFiore, Amanda, Abdullatif Zaouk, and S. K. (John) Punwani. "Next Generation Locomotive Cab." In ASME 2012 Rail Transportation Division Fall Technical Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/rtdf2012-9440.
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This paper discusses the development of a user-centered control stand for the Federal Railroad Administration’s (FRA) Next Generation Locomotive Cab (NGLC) demonstration program. A “modified” Association of American Railroads (AAR) 105 side-mounted control stand was used as a starting point to facilitate bidirectional locomotive operation. Researchers applied a variety of qualitative human factor methods, including literature review, naturalistic observation, computer modeling, and heuristic evaluation, to design the improved control stand. The final design included a decluttered side control stand, a short desktop with three-panel front touchscreen displays that can accommodate and integrate current and future locomotive train technologies, and an overhead ceiling panel that replaces, in part, controls and displays traditionally located behind the engineer on the back wall. A mockup of the revised control stand design was fabricated as part of this program to demonstrate the human factors and ergonomic improvements. Researchers conducted structured interviews with locomotive engineers to validate the user-centered design approach. The engineers engaged in interactive scenarios that assessed the functionality of the workspace. The usability results provided the opportunity to improve upon the initial NGLC user-centered design. Changes included minor relocation of controls because they were in the reach path of other controls. Certain frequently accessed controls required relocation to more accessible locations. The LCD displays were redesigned with respect to information groupings and visibility issues. Feedback revealed that the transition from mechanical operations to electronic operations will result in the loss of auditory cues inherent in mechanical operations. The researchers suggest simulating auditory cues to promote personnel transition from mechanical to electronic operations. The results of this usability assessment identify the opportunity for future R&D cab integration efforts and demonstrate the importance of user-centered design and usability assessment in these efforts.
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Praetorius, Gesa, and Charlott Sellberg. "Exploring strengths and weaknesses in professional marine pilot education." In 13th International Conference on Applied Human Factors and Ergonomics (AHFE 2022). AHFE International, 2022. http://dx.doi.org/10.54941/ahfe1002502.
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Marine pilotage is one of the foremost measures to increase maritime safety and decrease the risk for hazards in areas that are challenging to navigate in, such as in and out of ports. Pilotage is usually carried out by marine pilots, who are mariners with local expertise that support and consult a vessel’s master in navigational matters. Their work enables an effective communication with local and shore-based service, thus promoting a safe passage. As pilots play a crucial role in ensuring maritime safety and protecting the environment, training and education play a particularly important role. This study presents findings from a focused group interview that was conducted with five experienced pilots, who also work as instructors within the Swedish marine pilot education. The aim of the interview was to explore strengths and weaknesses in today’s education, as well as to identify potential opportunities and threats. Furthermore, the focus group also intended to highlight potential future directions for improvements of the professional education and training. While the SWOT-analysis was originally developed as a tool for strategic planning in fields like marketing, in recent years we are starting to notice an increase in applications, not at least in Human Factors research. Thus, the interest was to further explore the usefulness for conducting SWOT-analyses in research projects related to professional education programs.The results from the SWOT-analysis show that the training and education is strengthened by the wide variety of practical experiences that the instructors gain from actively working as pilots. Furthermore, the advantage of being able to use real-life experience to design training units increases the relevance of the theoretical knowledge for the trainees and is likely to impact on the overall transferability between training and work settings. However, the experts also highlight that there is a general lack of organizational support and pedagogical training, which may affect the training’s quality and delivery. Furthermore, it was also stressed that there is a lack of short- and long-term evaluation, so it remains unknown what parts of the education are successful and where potential improvements are necessary. The discussions among the experts also highlighted that training is a precondition to become a marine pilot, but that there is need to gain a deeper understanding for traits and competences that shape the preconditions for being a skilled pilot, as well as experience as master mariner is critical, but that experience may not naturally transfer into expertise. Finally, non-technical and interpersonal skills were highlighted as being the crucial for becoming pilot and that there might be too little focus on how to develop these skills in comparison to shiphandling and other technical skills. While the interview was specifically focused on marine pilots, the highlighted strengths, and weaknesses, as well as potential improvements may also be applicable to other professional education programs. In particular, a SWOT-analysis can be a useful tool to start to identify topics for further explorations in new research projects related to professional education programs.
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Abrahamsson, Lars, Daniel Serrano Jimenez, John Laury, and Math Bollen. "AC Cables Strengthening Railway Low Frequency AC Power Supply Systems." In 2017 Joint Rail Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/jrc2017-2258.
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In present-day railway power supply systems using an AC frequency lower than the one in the public power system of 50/60 Hz, high voltage overhead transmission lines are used as one measure of strengthening the railway power supply system grids. This option may be economically beneficial, compared to strengthening the grid purely by increasing the density of converter stations or increasing the cross section areas of the overhead catenary wires. High voltage AC transmission lines in the railway power supply system allow larger distances between converter stations than would otherwise be possible for a given amount of train traffic. Moreover, the introduction of AC transmission lines implies reduced line losses and reduced voltage level fluctuations at the catenary for a given amount of train traffic. However, due to the increased public and government resistance for additional overhead high voltage AC transmission lines in general, different alternatives will be needed for the future improvements and strengthening of railway power systems. For a more sustainable transport sector, the share and amount of railway traffic needs to increase, in which case such a strengthening becomes inevitable. Earlier, usage of VSC-HVDC transmission cables has been proposed as one alternative to overhead AC transmission lines. One of the main benefits with VSC-HVDC transmission is that control of power flows in the railway power systems is easier and that less converter capacity may be needed. Technically, VSC-HVDC transmission for railway power systems is a competitive solution as it offers a large variety of control options. However, there might be other more economical alternatives reducing the overall impedance in the railway power system. In public power systems with the frequency of 50/60 Hz, an excess of reactive power production in lowly utilized cables imposes an obstacle in replacing overhead transmission lines with cables. In low frequency AC railway power system, the capacitive properties are less significant allowing longer cables compared to 50/60 Hz power systems. Moreover, in converter-fed railways, some kind of reactive compensation will automatically be applied during low-load. At each converter station, voltage control is already present following the railway operation tradition. Therefore, in this paper, we propose AC cables as a measure of strengthening low-frequency AC railway power systems. The paper compares the electrical performances of two alternative reinforcement cable solutions with the base case of no reinforcement. The options of disconnecting or toggling the cables at low load as well as the automatic reactive compensation by converter voltage control are considered. Losses and voltage levels are compared for the different solutions. Investment costs and other relevant issues are discussed.
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Long, Steven, Geb W. Thomas, and Donald D. Anderson. "Designing an Extensible Wire Navigation Simulation Platform." In 2017 Design of Medical Devices Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/dmd2017-3435.
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Orthopaedic resident training has been, and continues to be, in a state of flux. Initially, there were limits placed on the number of hours a resident could work in a week [1]. Later, residency programs were required to provide laboratory-based training in basic surgical skill for first year residents [2]. Now there is a push towards a competency-based training program that graduates residents who demonstrate their acquisition of adequate surgical skills [3]. With each of these shifts in the training model, programs and institutions have looked increasingly to simulation-based training to ease the way. Simulation offers opportunities to train surgeons quickly, provide essential feedback to foster improvement, and assess skill acquisition. With the broad swath of requirements to satisfy in orthopaedic surgical skills training, a simulation platform must support an array of training capabilities for resident practice and performance assessment. Wire navigation is a central skill in orthopaedics that has a broad variety of applications. In this task, surgeons must use 2D intra-operative fluoroscopic images to visualize the 3D anatomy of a patient and place a wire along a specified path through bone. In some situations, placing the wire is the final task; in others the wire serves as a guide for subsequently placed cannulated implants. Regardless of the situation, the placement of the wire in the bone directly influences the surgical result for the patient. We previously presented the design of a wire navigation surgical simulator dedicated specifically to hip wire navigation [4]. Our experience with the dozens of surgeons and residents who have used the simulator suggest that they find the general skill of guiding a wire to be relatively abstract. They are more drawn to practicing specific surgeries rather than the general skill. To address this need, we have modified the simulator to present new surgical procedures, while still exercising the underlying skill of wire navigation. We also learned that the task of directing the fluoroscope in order to acquire appropriate view angles for making surgical decisions is integral to surgical wire navigation, so we extended the simulator to include this important aspect of surgical skill.
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Ren, Pangbo, Charles Stuart, Stephen Spence, Ryosuke Inomata, Takayuki Kobayashi, and Isao Morita. "Using Machine Learning for Loss Prediction in a Hybrid Meanline Modeling Method to Deliver Improved Radial Turbine Performance Prediction." In ASME Turbo Expo 2022: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/gt2022-80186.
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Abstract Low fidelity modelling approaches remain attractive due to an unrivalled ability to predict full turbine performance maps quickly compared to high fidelity approaches such as CFD, especially in the preliminary design process. As improvements in performance on a component level approach a point of diminishing returns, the ability to efficiently optimize the complete charging system for a given duty is a topic attracting significant research interest. In the case of turbocharging applications, existing engine and powertrain simulations require turbine maps to calculate the turbine performance, which are usually obtained from experimental testing. Unfortunately, the need for extrapolation is unavoidable because of the limited range of testing data available, leading to inaccuracies especially at off-design conditions. To enable intensive modelling and optimization of complete vehicle powertrains for different drive cycles, the current piece of work seeks to combine the advantages of machine learning techniques and physical meanline modelling to facilitate faster, more accurate predictions of complete turbocharger maps. This paper presents a novel methodology for turbocharger turbine rotor and nozzle performance prediction based on hybrid modelling. The turbine rotor and nozzle were parameterized to conduct CFD simulations for a wide variety of turbine geometries, which were used to form a database to train an Artificial Neural Network (ANN). The predicted losses provided by the ANN were then utilized in the meanline code, substituting for the conventional empirical loss models. As well as removing the need for empirical loss models, modifications were undertaken to the meanline approach to further enhance modelling accuracy. Firstly, in order to accurately characterize the stage mass flow capacity, the losses occurring in the nozzle and rotor were subdivided into those occurring before and after the throat. A second novel aspect is that the aerodynamic blockage level at the rotor throat was implemented as a variable rather than a constant value. By training the ANN to predict the variation of blockage with geometry and operating condition, a more accurate depiction of the changing secondary flow fields could be achieved. The capabilities of the hybrid meanline modelling method were evaluated on several unseen test cases. The resulting predictions of efficiency and mass flow rate demonstrated strong correlation with CFD results and experimental test results. The hybrid meanline modelling method therefore displays great potential in wide range radial turbine performance prediction with enhanced accuracy in comparison to traditional approaches.
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Gonzales, Kari, Kevin Koch, and Daniel Carter. "Improving the Quality and Reliability of Large Truck Castings." In 2011 Joint Rail Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/jrc2011-56057.
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Recent failures of large freight car castings have resulted in a comprehensive review of the specifications governing the manufacture, inspection, and repair of these steel castings. As part of an overall industry effort to improve the quality and reliability of large freight car castings, the Transportation Technology Center, Inc. (TTCI) conducted finite element and fatigue analyses of the S-2-HD bolster and side frame. The objective of this project is to improve the capacity and safety of train operations by reducing the number of in-service failures of bolsters and side frames. To meet the objective, a total of six S-2-HD bolster and side frame castings from different manufacturers were modeled to estimate the fatigue life of each of the components with and without defects. The results from the finite element analysis were combined with load/stress environment data and mechanical test data to predict the fatigue life of each of the components. The fatigue life analysis covered a variety of defect and no defect conditions and used a strain-life based approach. All of the fatigue estimates are based on life until crack initiation and compared to a target life of 1.5-million loaded miles. Results from the analysis show that few combinations of casting design and defect type/size offer sufficient fatigue strength to reach a target life of the desired 1.5-million loaded miles. The analyses also indicate that a reduction in component stress is necessary to improve the overall fatigue performance of the S-2-HD bolster and side frame castings when defects are present in critical stress areas. To reduce the number of derailments associated with truck castings, improvements in component design, manufacturing processes, and materials are necessary. Implementation of changes in design and materials has the potential to reduce stress in critical areas and increase fatigue life performance when defects are present. In addition, it is critical to develop inspection methods capable of reliably detecting defects to prevent in-service failures. If the aforementioned changes are implemented successfully, there is a potential of reducing in-service failures of truck castings by approximately 30 percent. This paper presents the approach and results of the bolster analysis and gives a brief summary of the results of the side frame analysis.
Reports on the topic "Varietal trait improvements"
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Katzir, Nurit, James Giovannoni, and Joseph Burger. Genomic approach to the improvement of fruit quality in melon (Cucumis melo) and related cucurbit crops. United States Department of Agriculture, June 2006. http://dx.doi.org/10.32747/2006.7587224.bard.
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Fruit quality is determined by numerous genetic traits that affect taste, aroma, texture, pigmentation, nutritional value and duration of shelf-life. The molecular basis of many of these important traits is poorly understood and it’s understanding offers an excellent opportunity for adding value to agricultural products. Improvement of melon fruit quality was the primary goal of the project. The original objectives of the project were: The isolation of a minimum of 1000 fruit specific ESTs. The development of a microarray of melon fruit ESTs. The analysis of gene expression in melon using melon and tomato fruit enriched microarrays. A comprehensive study of fruit gene expression of the major cucurbit crops. In our current project we have focused on the development of genomics tools for the enhancement of melon research with an emphasis on fruit, specifically the first public melon EST collection. We have also developed a database to relay this information to the research community and developed a publicly available microarray. The release of this information was one of the catalysts for the establishment of the International Cucurbit Genomic Initiative (ICuGI, Barcelona, Spain, July 2005) aimed at collecting and generating up to 100,000 melon EST sequences in 2006, leveraging a significant expansion of melon genomic resources. A total of 1000 ESTs were promised under the original proposal (Objective 1). Non-subtracted mature fruit and young fruit flesh of a climacteric variety in addition to a non-climacteric variety resulted in the majority of additional EST sequences for a total of 4800 attempted reads. 3731 high quality sequences from independent ESTs were assembled, representing 2,467 melon unigenes (1,873 singletons, 594 contigs). In comparison, as of June 2004, a total of 170 melon mRNA sequences had been deposited in GENBANK. The current project has thus resulted in nearly five- fold the number of ESTs promised and ca. 15-fold increase in the depth of publicly available melon gene sequences. All of these sequences have been deposited in GENBANK and are also available and searchable via multiple approaches in the public database (http://melon.bti.cornell.edu). Our database was selected as the central location for presentation of public melon EST data of the International Cucurbit Genomic Initiative. With the available unigenes we recently constructed a microarray, which was successfully applied in hybridizations (planned public release by August 2006). Current gene expression analyses focus on fruit development and on comparative studies between climacteric and non-climacteric melons. Earlier, expression profiling was conducted using macroarrays developed at the preliminary stage of the project. This analysis replaced the study of tomato microarray following the recommendations of the reviewers and the panel of the original project. Comparative study between melon and other cucurbit crops have begun, mainly with watermelon, in collaboration with Dr. Amnon Levi (USDA-ARS). In conclusion, all four objectives have been addressed and achieved. In the continuation project that have been approved we plan to apply the genomic tools developed here to achieve detailed functional analyses of genes associated with major metabolic pathway.