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Desirable Traits (desirable + trait)
Selected AbstractsInter-relationships Amongst Grain Characteristics, Grain-Filling Parameters and Rice (Oryza sativa L.) Milling QualityJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2001S. Jongkaewwattana Resistance to breakage is a desirable trait of the rice kernel. Many factors, such as the genetics of the cultivar, the plant growth environment and the conditions of the milling process, will affect kernel breakage. Although many papers have discussed the factors that may affect and improve rice milling quality, few have related the grain-filling process to head rice, the unbroken polished kernels obtained after milling. The objectives of this paper were: (i) to characterize the interrelationships amongst grain filling and grain structural characteristics; (ii) to determine whether the grain-filling process and grain characteristics affect head rice, and (iii) to suggest a pathway through which grain characteristics can influence head rice recovery. An analysis of the interrelationships amongst all grain characteristics suggested that variables of grain structure (size, volume and per cent hull) have a decisive influence on the grain-filling process (rate and duration of grain filling). The grain-filling process will affect final grain traits such as weight and density, which in turn will have a direct impact on head rice. In addition, non-uniformity, whether expressed in terms of variable grain size and shape or grain filling and maturity, has a detrimental effect on rice milling quality. The implication of these findings is that rice breeders need to pay more attention to selecting plant types that have a high degree of uniformity of grain characteristics on the panicle, and to those traits (such as greater grain size, weight and density) that have a positive impact on yield and milling quality. Beziehungen zwischen Korneigenschaften, Kornfüllungsparametern und Reis (Oryza sativa L.)-Vermahlungsqualität Bruchresistenz von Reiskörnern ist eine wünschenswerte Eigenschaft. Viele Faktoren, wie Genetik, Umwelt des Pfanzenwachstums und Voraussetzungen der Vermahlung, beeinflussen die Bruchresistenz der Körner. Obwohl viele Veröffentlichungen die Faktoren diskutieren, die die Mahlqualität beinträchtigen oder verbessern, beziehen sich nur wenige auf den Kornfüllungsvorgang zu ungebrochenen polierten Körner nach dem Mahlvorgang. Ziel der Untersuchungen war es: zu charakterisieren die Beziehungen zwischen Kornfüllung und Kornstruktur; zu bestimmen, ob der Kornfüllungsprozess und Korneigenschaften die Bruchresistenz von Reis beeinflussen können; und vorzuschlagen eine Behandlung durch die Korneigenschaften die Wiedergewinnung von Bruchreis beieinflußt werden kann. Eine Analyse der Beziehungen zwischen den Korneigenschaften weist darauf hin, dass Variable der Kornstruktur (Größe, Umfang und Antiel der Schale) einen deutlichen Einfluß auf den Kornfüllungsprozess haben (Rate und Dauer der Kornfüllung). Der Kornfüllungsprozess beeinflußt Korngewicht und Korndichte, die eine unmittelbare Auswirkung auf ungebrochene Körner nach dem Mahlvorgang haben. Auch Uneinheitlichkeit in Korngröße und Kornform oder Kornfüllung und Kornreife haben einen ungünstigen Einfluß auf die Vermahlungsqualität von Reis. Hieraus ergibt sich der Hinweis, daß Reiszüchter in der Selketion auf einen hohen Grad von Einheitlichkeit der Körner der Rispe und deren Eigenschaften (hohe Korngröße, Korngewicht und Korndichte), die einen Einfluß auf Ertrag und Mahlqualität haben, achten sollten. [source] Breeding of Pleurotus florida (oyster mushroom) for phenotypic pigmentation and high yield potentialJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2008Jatinder Kaur Abstract BACKGROUND: Cross-hybridisation is a technique for exchange of genetic material between two compatible nuclei to develop a recombinant genome with a probable expression for a desirable trait. This technique as an example of classical genetics has been applied in a heterothallic bifactorial/tetrapolar fungus Pleurotus florida. It has worked successfully during this study in a small number of experiments. RESULTS: Fruit bodies from the Pleurotus florida PAU-5 were allowed to shed their basidiospores on filter paper under aseptic conditions. Forty-nine monokaryons were isolated from three spore prints, namely Ja, Jb and K. Three hundred and fifty-six crosses were laid to result in five compatible reactions (PFJ4, PFJ9, PFJ11, PFJ13 and PFJ14). The fruit bodies of the hybrid dikaryon PFJ4 were found to show grey pigmentation. The hybrid dikaryons PFJ11 and PFJ14 grew faster in wheat straw substrate to take 39 and 41 days, respectively, for complete mycelial impregnation as compared to the parent, PAU-5 (48 days). The dikaryon PFJ11 out-yielded the parent by giving 34.2% biological efficiency compared to 29.8% for the parent. CONCLUSION: Through cross-hybridisation various changes at the genetic level are possible, showing altered phenotypic expression of the characters, such as change in fruiting efficiency and variability in fruit body characteristics (e.g., pileus shape and pigmentation). This technique can also be applied to other crops to improve their yield potential and bring about desirable phenotypic changes. Copyright © 2008 Society of Chemical Industry [source] Application of genomics to grapevine improvementAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 2010G. DI GASPERO Abstract Imagine a breeder browsing a grape chromosome nucleotide-by-nucleotide around a trait locus, scrolling down the list of catalogued genes along a genetic interval, resequencing for a few thousand dollars a potential parent or a selected breeding line. In the past couple of years, this vision has become a reality. The availability of the reference genome sequence has provided significant assistance in the saturation of loci with targeted genetic markers. Grape breeders are now offered unprecedented possibilities for selecting plants using deoxyribonucleic acid (DNA) sequences within or near the gene that controls a desirable trait rather than handling their phenotypes. Genomics-assisted selection offers unique advantages in the correct choice of elite genotypes, in order to improve traits for which limitations of phenotyping technologies or low hereditability adversely affect the efficiency of phenotypic selection. DNA technologies enable the application of marker-assisted selection to thousands of grape seedlings every year, which was previously feasible only for cereals and annuals, enhancing the possibilities of finding an ideal recombinant in populations bred from highly heterozygous parents. The expected outcome is a renewal of the varietal choices available to viticulturists, with novel genotypes that meet the demand for disease-free vines and flavourful grapes. The depth of exploration and characterisation of the existing germplasm is crucial for translating natural diversity into new varieties that could perform beyond the fence of the experimental vineyards and gain substantial market share. We review here how current achievements in genomics and genome sequencing are expected to increase the efficiency of grapevine breeding programs. [source] Extreme breeding: Leveraging genomics for crop improvementJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2007Siobhan M Brady Abstract The genomic revolution has led to dramatic increases in our understanding of plant biology in the past 10 years, especially in model plant species such as Arabidopsis. The technologies associated with this revolution, such as tilling, array mapping, and association mapping, will see widespread application to crop improvement in the near future. The genes for desirable traits identified through such efforts may be introgressed at an accelerated rate into elite germplasm by marker-assisted breeding. Copyright © 2007 Society of Chemical Industry [source] Production and characterization of an amphiploid between common wheat and Psathyrostachys huashanica Keng ex KuoPLANT BREEDING, Issue 1 2009H. Y. Kang Abstract Wide crosses and synthetic amphiploids have played an important role in introgressing desirable traits from related species into cultivated wheat. Hybrids between Triticum aestivum cv. ,J-11' and Psathyrostachys huashanica were treated with colchicine, to produce a new intergeneric amphiploid (PHW-SA). The morphological characteristics of PHW-SA resembled the parent ,J-11'. PHW-SA plants have purple internodes and pubescence in the basal spikelet, inherited from the P. huashanica parent. Somatic chromosome numbers varied from 2n = 51 to 2n = 56, with 70.59% of plants having 56 chromosomes. At metaphase I, PHW-SA (2n = 56) plants showed an average of 1.15 univalents, 27.34 bivalents, 0.03 trivalents and 0.02 tetravalents per cell; complete chromosome pairing occurred in 50% of the pollen mother cells. A survey of disease resistances revealed that the stripe rust resistance from P. huashanica was expressed, but powdery mildew resistance was suppressed. The fertility of PHW-SA was 60%. [source] Ethics and Genetic Selection in Purebred DogsREPRODUCTION IN DOMESTIC ANIMALS, Issue 1 2003VN Meyers-Wallen Contents There is an ongoing revolution in medicine that is changing the way that veterinarians will be counselling clients regarding inherited disorders. Clinical applications will emerge rapidly in veterinary medicine as we obtain new information from canine and comparative genome projects (Meyers-Wallen 2001: Relevance of the canine genome project to veterinary medical practice. International Veterinary Information Service, New York). The canine genome project is described by three events: mapping markers on canine chromosomes, mapping gene locations on canine chromosomes (Breen et al. 2001: Genome Res. 11, 1784,1795), and obtaining the nucleotide sequence of the entire canine genome. Information from such research has provided a few DNA tests for single gene mutations [Aguirre 2000: DNA testing for inherited canine diseases. In: Bonagura, J (ed), Current Veterinary Therapy XIII. Philadelphia WB Saunders Co, 909,913]. Eventually it will lead to testing of thousands of genes at a time and production of DNA profiles on individual animals. The DNA profile of each dog could be screened for all known genetic disease and will be useful in counselling breeders. As part of the pre-breeding examination, DNA profiles of prospective parents could be compared, and the probability of offspring being affected with genetic disorders or inheriting desirable traits could be calculated. Once we can examine thousands of genes of individuals easily, we have powerful tools to reduce the frequency of, or eliminate, deleterious genes from a population. When we understand polygenic inheritance, we can potentially eliminate whole groups of deleterious genes from populations. The effect of such selection on a widespread basis within a breed could rapidly improve health within a few generations. However, until we have enough information on gene interaction, we will not know whether some of these genes have other functions that we wish to retain. And, other population effects should not be ignored. At least initially it may be best to use this new genetic information to avoid mating combinations that we know will produce affected animals, rather than to eliminate whole groups of genes from a population. This is particularly important for breeds with small gene pools, where it is difficult to maintain genetic diversity. Finally, we will eventually have enough information about canine gene function to select for specific genes encoding desirable traits and increase their frequencies in a population. This is similar to breeding practices that have been applied to animals for hundreds of years. The difference is that we will have a large pool of objective data that we can use rapidly on many individuals at a time. This has great potential to improve the health of the dog population as a whole. However, if we or our breeder clients make an error, we can inadvertently cause harm through massive, rapid selection. Therefore, we should probably not be advising clients on polygenic traits or recommend large scale changes in gene frequencies in populations until much more knowledge of gene interaction is obtained. By then it is likely that computer modelling will be available to predict the effect of changing one or several gene frequencies in a dog population over time. And as new mutations are likely to arise in the future, these tools will be needed indefinitely to detect, treat and eliminate genetic disorders from dog populations. Information available from genetic research will only be useful in improving canine health if veterinarians have the knowledge and skills to use it ethically and responsibly. There is not only a great potential to improve overall canine health through genetic selection, but also the potential to do harm if we fail to maintain genetic diversity. Our profession must be in a position to correctly advise clients on the application of this information to individual dogs as well as to populations of dogs, and particularly purebred dogs. [source] Production of Hepatitis B Surface Antigen in Recombinant Plant Systems: An UpdateBIOTECHNOLOGY PROGRESS, Issue 3 2007G. B. Sunil Kumar There is a growing interest to develop oral vaccines for infectious diseases, as it is the most convenient and effective way to attain mucosal immunity. Hepatitis B continues to be a major infectious disease in many developing countries despite the availability of recombinant vaccine. On a global scenario, Hepatitis B Virus infection is probably the single most prevalent cause of persistent viraemia in humans. There are about 350 million chronic carriers of HBV, which is about 5% of the total world population. It is estimated that 75,100 million of them will die of liver cirrhosis and/or hepatocellular carcinoma. Progress in plant genetic engineering has enabled the transfer of useful genes for desirable traits. The recent trend is to use this technique to exploit plants as biofactories for the production of therapeutic proteins including vaccines. Rapid progress has been made in this area to develop plant-based vaccines for hepatitis B. This review describes the expression, characterization, and immunogenicity studies of hepatitis B vaccines produced in recombinant plant systems and their implications for developing a plant-based vaccine. [source] Single-point mutations at the surface of MB-1Trp lead to important changes in its conformational propertiesCHEMICAL BIOLOGY & DRUG DESIGN, Issue 1 2004M. Sasseville Abstract:, Protein design is currently used for the creation of new proteins with desirable traits. In our lab we focus on the synthesis of proteins with high essential amino acid content having potential applications in animal nutrition. One of the limitations we face in this endeavour is achieving stable proteins despite a highly biased amino acid content. We report here the synthesis and the characterization of three variants of MB-1Trp in which two solvent-exposed Leu have been replaced by Glu allowing for the formation of new salt bridges at the surface of the protein. Although both mutations were expected to be similar (i.e. same mutation in a comparable local environment), they appear to have different effects on MB-1Trp as shown by far-UV circular dichroism, thermal denaturation, fluorescence and proteolytic resistance measurements. For the mutation Leu68Glu, an increase in the protein melting temperature of 6 °C was observed. Surprisingly, the mutation in position Leu19Glu led to a decrease in melting temperature and a modification of tertiary structure. [source] The regulatory and business roles of a Study DirectorQUALITY ASSURANCE JOURNAL, Issue 4 2005Celeste A. Rose Abstract The role of Study Director can be a challenging one with technical, administrative, and compliance responsibilities. The Study Director often does not have direct responsibility for personnel and other resources required for his/her studies. In this article, we have attempted to identify traits and mechanisms to help the Study Director do his/her job in a professional and compliant manner. In addition to regulatory and scientific expertise, Study Director quality attributes include possession of appropriate soft skills and character traits and are key to the success of a study. Study Directors must have an aptitude for effective communication, relationship building, training, mentoring, and delegation. While these soft skills/desirable traits often require additional effort on the part of the Study Director, they have a large impact on the rate of success, efficiency, and compliance of the study overall. The workshop presented by the authors took a 'hands-on' approach building on the creativity, and experience of Study Directors, supervisors, managers, and Quality Assurance (QA) personnel who participated. The participants deliberated problem scenarios from a Study Director's perspective. The tables and discussion in this article summarize compliant solutions, which arose from the resourcefulness that comes from experience of the participants. Copyright © 2005 John Wiley & Sons, Ltd. [source] | |||||||||||||