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Genetic Improvement Programmes (genetic + improvement_programme)
Selected AbstractsBiochemical Changes in Leaf Tissues of Taro [Colocasia esculenta L. (Schott)] Infected with Phytophthora colocasiaeJOURNAL OF PHYTOPATHOLOGY, Issue 3 2010Manas Ranjan Sahoo Abstract The changes in some biochemical parameters due to Phytophthora leaf blight infection were assessed in leaf tissues of one resistant (DP-25), two moderately resistant (Duradim and Jhankri) and one susceptible (N-118) genotypes of taro [Colocasia esculenta (L.) Schott]. Phytophthora spore suspension (15 000 spore/ml water) was sprayed onto the in vitro raised taro plantlets at 30 days after establishment in pots to induce disease. In comparison with the uninoculated leaves, blight infected leaves showed reduction in protein content and activity of nitrate reductase and increase in total soluble sugar, reducing sugar content and activities of acid phosphatase and alkaline phosphatase among the studied genotypes. Changes in biochemical parameters under induced blight stress as compared with uninoculated control were less in resistant genotypes than that in susceptible genotype. The deviations in biochemical contents were highest in susceptible genotype N-118. Based on the variations of above parameters under stress and non-stress control among the four tested genotypes, the overall pattern of changes was N-118 > Duradim > Jhankri > DP-25, which is in accordance with the pattern of increasing resistance. The resistant genotypes could be used for commercial cultivation and genetic improvement programme to develop resistant varieties to Phytophthora leaf blight disease. [source] Climate change and the characterization, breeding and conservation of animal genetic resourcesANIMAL GENETICS, Issue 2010Irene Hoffmann Summary Livestock production both contributes to and is affected by climate change. In addition to the physiological effects of higher temperatures on individual animals, the consequences of climate change are likely to include increased risk that geographically restricted rare breed populations will be badly affected by disturbances. Indirect effects may be felt via ecosystem changes that alter the distribution of animal diseases or affect the supply of feed. Breeding goals may have to be adjusted to account for higher temperatures, lower quality diets and greater disease challenge. Species and breeds that are well adapted to such conditions may become more widely used. Climate change mitigation strategies, in combination with ever increasing demand for food, may also have an impact on breed and species utilization, driving a shift towards monogastrics and breeds that are efficient converters of feed into meat, milk and eggs. This may lead to the neglect of the adaptation potential of local breeds in developing countries. Given the potential for significant future changes in production conditions and in the objectives of livestock production, it is essential that the value provided by animal genetic diversity is secured. This requires better characterization of breeds, production environments and associated knowledge; the compilation of more complete breed inventories; improved mechanisms to monitor and respond to threats to genetic diversity; more effective in situ and ex situ conservation measures; genetic improvement programmes targeting adaptive traits in high-output and performance traits in locally adapted breeds; increased support for developing countries in their management of animal genetic resources; and wider access to genetic resources and associated knowledge. [source] Evaluation of SPATA1 -associated markers for stallion fertilityANIMAL GENETICS, Issue 4 2009K. Giesecke Summary Stallion fertility is an economically important trait because the use of artificial insemination is increasing in the horse industry and superior sires are used more intensely. Molecular genetic markers may be useful as early indicators for a stallion's fertility and genetic improvement programmes. The testis-specific SPATA1 protein is involved in shaping the sperm head during spermatogenesis. Thus, the spermatogenesis associated 1 (SPATA1) gene was chosen as candidate for stallion fertility, and we analysed intragenic single nucleotide polymorphisms (SNPs) as genetic markers for the least square means (LSM) of the pregnancy rate per oestrus of stallions and breeding values (BV) for the paternal and embryonic component of the pregnancy rate per oestrus. We sequenced the cDNA of SPATA1 to verify the annotated mRNA sequence. One SPATA1 -associated intronic SNP (BIEC2-968854) showed a significant association with the embryonic component of BVs of stallions for the pregnancy rate per oestrus. The embryonic component of BVs was positively associated with homozygous C/C stallions. Both the additive and dominance effects were significant with values of ,5.8% (P = 0.01) and ,6.4% (P = 0.02) for the embryonic component of BVs. For the same SNP, a suggestive association was found for the LSM of the pregnancy rate per oestrus of stallions. Heterozygous stallions had higher pregnancy rates per oestrus than homozygous stallions. The dominance effect was 4.1% with a nominal P -value of 0.02. The SNP BIEC2-968854 can change an SP1 binding site and thus we assume that gene regulation may be influenced through this intronic mutation. This is the first report on SPATA1 being associated with the pregnancy rate per oestrus for stallions. [source] B-F DNA sequence variability in Brazilian (blue-egg Caipira) chickensANIMAL GENETICS, Issue 4 2004C. A. V. Lima-Rosa Summary A total of 100 chickens from the Brazilian (blue-egg Caipira) native breed were studied in relation to exon 2 of the B-F genes of the major histocompatibility complex (MHC) region. After a first screening on 100 birds, 22 animals were selected for amplification, cloning and sequencing experiments of exons 2,4 (a total of 1048 bp) of their DNA. Twenty-three sequences were obtained, of which at least 10 appear novel. Inferred protein sequences were compared with those previously described, totalling 41 different sequences with amino acid changes in 33 of the 88 sites in ,1, and 34 of the 91 sites in ,2 domains. Allele expression was investigated in these animals through cloning experiments. The blue-egg Caipira chickens may provide a source of novel B-F alleles for genetic improvement programmes. [source] Genetic improvement in the Australian aquaculture industryAQUACULTURE RESEARCH, Issue 1 2000A J. Lymbery Most aquaculture industries in Australia are at an early stage of development and would benefit from the introduction of genetic improvement programmes. Size at harvest is perceived by industry participants, managers and researchers as the trait that will most influence profitability. Although most current genetic improvement programmes in aquaculture use mass selection, inbreeding is widely regarded as an important problem, which could be overcome by the use of family data in selection decisions. The major research priority is the development of genetic markers to enable accurate pedigree determination. The major constraint upon the implementation of genetic improvement programmes by aquaculture industries is lack of available funds and resources. Industry ownership and national co-ordination of research and development is seen as the best way of addressing this constraint. [source] | ||||||||||