Natural resistance to Potato virus Y in <i>Solanum tuberosum</i> Group Phureja

This work was supported by funding from the Scottish Government’s Rural and Environmental Science and Analytical Services (RESAS) Division.A new source of genetic resistance derived from Solanum tuberosum Group Phureja against Potato virus Y (PVY) was identified and genetically characterised in three diploid biparental potato populations. Segregation data for two populations (05H1 and 08H1) suggested the presence of a single dominant gene for resistance to PVY which, following DaRT analysis of the 08H1 cross, was mapped to chromosome 9. More detailed genetic analysis of resistance utilised a well-characterised SNP-linkage map for the 06H1 population, together with newly generated marker data. In these plants, which have both S. tuberosum Group Phureja and S. tuberosum Group Tuberosum in their pedigree, the resistance was shown to map to chromosome 9 at a locus not previously associated with PVY resistance, although there is evidence for at least one other genetic factor controlling PVY infection. The resistance factor location on chromosome 9 (named as Ry(o)phu) suggests a potential role of NB-LRR genes in this resistance. Phenotypic analysis using a GUS-tagged virus revealed that a small amount of PVY replication occurred in occasional groups of epidermal cells in inoculated leaves of resistant plants, without inducing any visible hypersensitive response. However, the virus did not enter the vascular system and systemic spread was completely prevented.Publisher PDFPeer reviewe

The Chester News May 15, 1923

The Chester News was a semi-weekly, later weekly continuation of the Semi-Weekly News established in 1913. The name changed to the Chester News in September 1917 retaining the number sequence of the Semi-Weekly News. In 1917 it was a semi-weekly Democrat newspaper. About 1942, it became a weekly paper. W. Ward Pegram and Stewart L. Cassells were the owner/publishers. W. Ward Pegram, Jr. took ownership after his father’s death and published the paper until September 1971 when it merged with the Chester Reporter to form the News and Reporter which is still in publication.https://digitalcommons.winthrop.edu/chesternews1923/1035/thumbnail.jp

An investigation into how grade 10 learners make meaning during the teaching and learning of the topic on nutrition in Life Science: a case study

The integration of learners’ prior everyday knowledge and experiences during teaching and learning is a pre-requisite in the Namibian curriculum. The curriculum states that if learners are taught in a way which builds on what they already know and they relate new knowledge to the reality around them, their learning in school can be made more meaningful. Thus, learners’ meaning making in the topic on nutrition was researched to find out whether elicitation and integration of learners’ prior everyday knowledge and experience in the nutrition topic enhanced or constrained their learning. This study was conducted with my grade10 learners at the school where I am currently teaching. The school is located in a rural area in Oshana region in Northern Namibia. This study is situated within an interpretive paradigm. Within the interpretive paradigm a qualitative case study approach was adopted. I considered this methodological orientation appropriate in this study as it allowed me to use the following methods: document analysis, brainstorming and discussion, semi-structured interviews and a focus group interview, practical activities with worksheets and observation and reflection. Multiple methods to gather data were used for triangulation and validation purposes. For data analysis purposes, the data sets were colour coded to derive themes and analytical statements. Ethical consideration was also taken seriously in this study. The findings from this study revealed that integration of learners’ prior everyday knowledge and experience enabled learners to understand science better particularly in the topic of nutrition. The study also revealed that learners possess a lot of prior everyday knowledge and experience about food they eat in their homes. However, data from the community members revealed that there are some contradictions between learners’ prior everyday knowledge and the science content of the topic. Nonetheless, engaging learners in practical activities in the testing of food (local and conventional western type foods) helped them to make meaning of the content learned. I therefore, recommend that learners’ prior everyday knowledge and experiences should be incorporated during teaching and learning of the topic on nutrition. The study also recommends that the Department of Education should ensure that teachers get the necessary support and training on how to integrate learners’ prior everyday knowledge and experiences