Conference Posters
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Item Exploring root traits associated with increased yield under water deficit in perennial ryegrass (Lolium perenne L.) germplasm of Mediterranean and European origins.(2015-10) Huassion S; Matthew C; Naeem M; Easton HSExploring root traits associated with increased yield under water deficit in perennial ryegrass (Lolium perenne L.) germplasm of Mediterranean and European origins Sajjad Hussain1, Cory Matthew2, Muhammad Naeem3, H. Sydney Easton4 1Plant Genetic Resources Institute, National Agricultural Research Center, Islamabad, Pakistan, 2Institute of Agriculture and Environment, Massey University, Palmerston North, New Zealand, 3Federal Seed Certification and Registration Department, Islamabad, Pakistan, 4AgResearch, Palmerston North, New Zealand. Contact: shmalik25@hotmail.com Introduction Perennial ryegrass (Lolium perenne L.) is now one of the most widely used forage grass species in temperate pastoral agriculture and in recent years breeding for improved performance in summer drought conditions has become a focus. Germplasm of Spanish origin has been widely used in New Zealand plant breeding (Stewart, 2006), but another possibility that has attracted comparatively little research to date is introgression of summer dormant germplasm of North African origin with material of European origin. Methods Plants of a New Zealand-bred perennial ryegrass cultivar “Grasslands Samson”, a summer dormant Australian cultivar “Medea” developed in the 1960’s from germplasm of Mediterranean origin (Silsbury, 1961), and the F1 and F2 progenies of the two parents were compared during summer 2010-11 in a glasshouse study at Palmerston North, New Zealand. The experiment compared rooting behavior and herbage yield of the two cultivars and studied the pattern of inheritance of those traits to F1 and F2 progeny. Plants grown in 100 cm lengths of soil-filled PVC pipes were initially bottom-watered in 200 liter drums and then drought was imposed by gradually lowering the water table until plants survived on water retained in the soil profile. At a concluding destructive harvest, herbage yield (DW) and tiller number (TN) were recorded, while total root mass (Rt), coarse root mass (Rc) fine root mass (Rf) and gravimetric soil moisture % (SMC) were all measured for three soil depths (0-30, 30-60 and below 60 cm). From these data root:shoot ratio (R:S), deep root (below 30 cm): shoot ratio (DR:S), an index of deep rooting (% total root below 30 cm, IDR), and DW/(0.2 – SMC) as an index of efficient water use (IEWU) were derived. Results and Discussion Medea exhibited deep rooting compared to Grasslands Samson indicated by higher R:S, DR:S and IDR, that had never been studied since its release in Australia. However, it had lower IWU, 83% lower DW and 87% lower TN than Grasslands Samson – a characteristic of Mediterranean origin pasture species. On the question of introgressing root traits of Medea to Grasslands Samson: in the F1 generation, some plants surpassed Medea for some root traits (eg DR:S and IDR), while F2 plants were similar to Grasslands Samson parents, However, within Grasslands Samson itself some plants showed high IEWU. Conclusion Introgression of Medea genes into Grasslands Samson will not be straight forward. However, direct selection for maintenance of growth under moderate water deficit with reduced soil moisture extraction per unit DW is an immediate option for improving drought tolerance in perennial ryegrass, providing the trait proves sufficiently heritable. Stewart AV (2006) Genetic origins of perennial ryegrass (Lolium perenne) for New Zealand Pastures. Pp11-20 In: Breeding for success: diversity in action, (ed, CF. Mercer) Proceedings of the 13th Australasian Plant Breeding Conference, Christchurch, NZ. Silsbury JH (1961) A study of dormancy, survival and other characteristics in Lolium perenne L. at Adelaide, SA. Aust. J. Ag. Res.12:1-9.Item A genome-wide scan of positive selection signature using Ovine Infinium® HD SNP BeadChip in two Romney lines, selected for resistance or resilience to nematodes(3/07/2017) Yan J; Dukkipati VSR; Blair HT; Biggs PJ; Hamie JC; Greer AA study was undertaken to identify selection signatures associated with resistance to gastrointestinal nematodiasis in sheep. Ninety-three Romney sheep from two selection lines (resistant or resilient) were genotyped using the Ovine Infinium® HD SNP BeadChip, and extended haplotype homozygosity (EHH) and site-specific extended haplotype homozygosity (EHHS) analyses were undertaken. In total, 224 SNPs (147 in EHH and 77 in EHHS) were found to be significant (p <0.0001). Preliminary exploration of 10 SNPs found them to be located within two previously identified QTLs, namely LATRICH_2 and FECGEN, which were associated with nematode larval count and faecal egg count, respectively.Item Engaging in spaces: How mature distance students fit study into their homes and lives(2/07/2013) Kahu ERIn order to fit study around family and work, a third of mature aged tertiary students in New Zealand study by distance. By enabling students to study when and where they want, distance study is said to overcome the barriers of space and time. But space and time must still be found and the blurring of the physical boundaries between study and home creates new challenges. While much has been written about how distance students juggle time, little has considered how they manage space; yet it is often the availability of an appropriate learning space that determines not just when and where they study, but the quality of their engagement. This qualitative study, following 19 mature aged distance students and their families through their first semester, examines how the students carved learning spaces from their busy lives, the nature of those spaces, and the impact this had on their engagement. For some, a space without other people was the essential characteristic and they achieved this through either a physical separation strategy such as studying at work, or a temporal separation strategy such as studying only when children were at school. For others, isolation was a barrier to their engagement and they gravitated to shared living spaces. Individual lifeload, context, and personal preference mean there are no right or wrong choices, but family support is a critical influence on the success of different strategies.Item New Zealand child and youth profile(8/06/2016) McLaughlin T; Budd JMEffective tools to better understand children’s functioning are critical to plan for and promote positive outcomes. The New Zealand Child and Youth Profile supports teams to reflect on and organize their understanding of a child’s strengths and limitations; sensory function; participation in key settings; and interests and preferences. The toolkit is designed to help teams identify priority areas for interventions. Preliminary results from a pilot study will be shared.Item Experiencing the educational interface: Understanding student engagement(3/07/2017) Kahu ER; Picton C; Nelson KStudent engagement is widely recognised as critical to student retention and success – simply put, students who are engaged with their studies are more likely to be successful. However, the mechanisms contributing to an individual student’s engagement have not yet been clearly articulated and the term engagement is used differently in various contexts. We understand engagement to be an individual student’s psychosocial state: their behavioural, emotional, and cognitive connection to their learning. In 1984, Astin proposed that student involvement, as he called it, was the missing link in our understanding of how institutional factors influenced student success. Aligned with Astin’s rationale, Chickering and Gamson (1987) proposed and later explored seven principles for good practice in undergraduate education, along with six ‘powerful forces’ that they believed shaped the student experience. In the decades since, these early contributions have strongly influenced curricular and co-curricular practices which have positively impacted on student outcomes. These practices include: peer to peer participation, access and interactions with staff, timely feedback, a scaffolded curriculum, early identification of students at risk, assessment aligned with learning outcomes, clearly articulated expectations, and a supportive but challenging learning environment. More recently, Students as Partners initiatives have been taken up with much enthusiasm. However, while the impact of these good practice initiatives has been comprehensively demonstrated, the mechanisms that explain how these initiatives actually influence an individual student’s retention and success have not yet been clearly identified. In 2013, Kahu proposed a comprehensive framework that shed light on the influences on and consequences of student engagement. In 2017 Kahu and Nelson refined this framework to include the notion of the educational interface as a metaphor for the individual psychosocial space within which a student is engaged in their learning. This new framework incorporates four key constructs within the interface, dimensions of the student’s psychosocial experience. These constructs are self-efficacy, belonging, emotions, and well-being. These four constructs represent pathways by which curricular and co-curricular initiatives and other factors influence student engagement and success. For instance, a student with financial difficulties or a heavy lifeload will have reduced well-being, which will inhibit their engagement with their studies. Or a student who forms good relationships with staff and peers will feel a sense of belonging which makes them more comfortable in class and thus more willing to actively participate. This revised framework is a leap forward in our understandings about the mechanisms that underpin student engagement and provide a firm foundation for practice. This poster presents and briefly explains the revised framework as well as illustrating the framework by presenting data from a current study following a group of 19 first year students at a regional Australian university for their first year. References Astin, A. W. (1984). Student involvement: A developmental theory for higher education. Journal of College Student Personnel, 25(4), 297-308. Chickering, A. W. & Gamson, Z. F. (1987). Seven principles for good practice in undergraduate education. American Association of Higher Education Bulletin, 39(7), 3-7 Kahu, E. R. (2013). Framing student engagement in higher education. Studies in Higher Education, 38(5), 758-773. doi: 10.1080/03075079.2011.598505 Kahu, E. R., & Nelson, K. (in press). Student engagement in the educational interface: Understanding the mechanisms of student success. Higher Education Research & DevelopmentItem Dissecting the Discourse of Social Licence to Operate(1/08/2018) Sinner J; Newton M; Farrelly TThe term “social licence to operate”, or SLO, has increasingly featured in public discussion about commercial operations in the marine environment. As part of the Sustainable Seas National Challenge, we are studying how this term is being used in New Zealand and its implications for industry-community relations.Item Structural determination of archaeal UDP-N-acetylglucosamine 4-epimerase from Methanobrevibacter ruminantium M1 in complex with the bacterial cell wall intermediate UDP-N-acetylmuramic acid(2/12/2018) Carbone V; Schofield L; Sang C; Sutherland-Smith A; Ronimus RSThe crystal structure of UDP-N-acetylglucosamine 4-epimerase (UDP-GlcNAc 4-epimerase; WbpP; EC 5.1.3.7), from the archaeal methanogen Methanobrevibacter ruminantium strain M1, was determined to a resolution of 1.65 Å. The structure, with a single monomer in the crystallographic asymmetric unit, contained a conserved N-terminal Rossmann fold for nucleotide binding and an active site positioned in the C-terminus. UDP-GlcNAc 4-epimerase is a member of the short-chain dehydrogenase/reductase superfamily, sharing sequence motifs and structural elements characteristic of this family of oxidoreductases and bacterial 4-epimerases. The protein was co-crystallized with coenzyme NADH and UDP-N-acetylmuramic acid, the latter an unintended inclusion and well known product of the bacterial enzyme MurB and a critical intermediate for bacterial cell wall synthesis. This is a non-native UDP sugar amongst archaea and was most likely incorporated from the Eschericha coli expression host during purification of the recombinant enzyme.Item OCCUPATIONAL EXPOSURE TO ELF-MF AND ELECTRIC SHOCKS AND MOTOR NEURONE DISEASE(4/09/2016) Chen GX; McLean D; van den Berg L; 't Mannetje A; Pearce N; Kromhout H; D'Souza W; McConnell M; Douwes JItem Combining Tn-seq with comparative genomics identifies proteins uniquely essential in Shigella flexneri(3/09/2015) Freed NE; Bumann D; Silander OProtein functions that are essential for the growth of bacterial pathogens provide promising targets for antibacterial treatment. This is especially true if those functions are uniquely essential for the pathogen, as this might allow the development of targeted antibiotics, i.e. those that disrupt essential functions only for the pathogenic bacteria. Here we present the results of a Tn-seq experiment designed to detect essential protein coding genes in Shigella flexneri 2a 2457T on a genome-wide scale. Our results suggest that 471 protein-coding genes in this organism are critical for cellular growth in rich media. Comparing this set of essential genes (the essential gene complement) with their orthologues in the closely related organism Escherichia coli K12 BW25113 revealed a significant number of genes that are essential in Shigella but not in E. coli, suggesting that the functional correspondence of these proteins had changed. Notably, we also identified a set of functionally related genes that are essential in Shigella but which have no orthologues in E. coli. We found an extreme bias in proteins that have evolved to provide essential functions, with many proteins essential in Shigella but not E. coli, but with none (or very few) being essential in E. coli but not Shigella. We also identify a set- of genes involved in nucleotide biosynthesis that are essential in Shigella, but which lack orthologues in E. coli. Consequently, the data presented here suggest that the essential gene complement can quickly become organism specific, especially for pathogenic organisms whose genomes might have reduced robustness in their metabolic capacity (e.g. functional redundancy), or a reduced numbers of protein coding genes. These results thus open the possibility of developing antibiotic treatments that target differentially essential genes, which may exist even between very closely related strains of bacteria.Item sFlt-1 and NTproBNP independently predict mortality in a cohort of heart failure patients.(2/12/2018) Paterson MA; Pilbrow AP; Frampton CM; Cameron VA; Pemberton CJ; Lund M; Devlin GP; Doughty RN; Richards AM; Palmer BObjective: Soluble fms-like tyrosine kinase-1 (sFlt-1) is a circulating receptor for VEGF-A. Recent reports of elevated plasma levels of sFlt-1 in coronary heart disease and heart failure (HF) motivated our study aimed at investigating the utility of sFlt-1 as a prognostic biomarker in heart failure patients. Methods: ELISA assays for sFlt-1 and NTproBNP were performed in n=858 patients from a prospective multicentre, observational study (the PEOPLE study) of outcome among patients after appropriate treatment for an episode of acute decompensated HF in New Zealand. Plasma was sampled at a baseline visit and stored at -80°C. Statistical tests were adjusted for patient age at baseline visit, skewed data were log-adjusted and the endpoint for clinical outcome analysis was all-cause death. Patients were followed for a median of 3.63 (range 0.74-5.50) years. Results: Mean baseline plasma sFlt-1 was 125 +/- 2.01 pg/ml. sFlt-1 was higher in patients with HF with reduced ejection fraction (HFrEF) (130 +/- 2.62 pg/ml, n=553) compared to those with HF with preserved EF (HFpEF) (117 +/-3.59 pg/ml, n=305; p=0.005). sFlt-1 correlated with heart rate (r=0.148, p<0.001), systolic blood pressure (r=-0.139, p<0.001) and LVEF (r=-0.088, p=0.019). A Cox proportional hazards model showed sFlt-1 was a predictor of all-cause death (HR=6.30, p<0.001) in the PEOPLE cohort independent of age, NTproBNP, ischaemic aetiology, and NYHA class (n=842, 274 deaths), established predictors of mortality in the PEOPLE cohort. Conclusion: sFlt-1 levels at baseline should be investigated further as a predictor of death; complementary to established prognostic biomarkers in heart failure.
