Predicting the Leaf Area of Vitis vinifera L. cvs. Cabernet Sauvignon and Shiraz

The planimetric area of grapevine leaf blades (LA) is required as input data in many grapevine growth models and quantitative studies of the soil/plant/atmosphere continuum. A subset of 300 scanned grapevine leaves was used to identify and compare allometric statistical models predicting the leaf area of grapevines (cultivars Cabernet Sauvignon and Shiraz). The mean absolute error (MAE), root mean square error (RMSE), and Δ (RMSE-MAE) were used as discriminatory criteria. Six families of models drawn from the literature were compared with stepwise regression using up to six possible predictor variables. Each family was fitted to each cultivar for three vineyard sites. Generic models were computed by aggregating the data across sites and cultivars. The Queensland (stepwise regressions) family performed best, closely followed by Elsner2 and Montero. The MAE of some generic models was at times less than that of their components because of the influence of sites and/or cultivars. Site-and cultivar-specific stepwise regressions are generally the most accurate methodology for estimating leaf surface area. Simple models were generally less accurate than models integrating several predictor variables. © 2010 by the American Society for Enology and Viticulture

Academic, industry and student perspectives on the inclusion of "vocational knowledge" in a 'learning and teaching academic standards statement' for agriculture

This paper reports on the perspective of industry stakeholders in a national project to develop a Learning and Teaching Academic Standards (LTAS) Statement for the Agriculture discipline. The AgLTAS Statement will be aligned with the Science LTAS Statement published in 2011 and comprise a discourse on the nature and extent of the Agriculture discipline and a set of Threshold Learning Outcome (TLO) statements specific to Agriculture. Agricultural research and teaching relies on strong links with industry due to the applied nature of the discipline. Without these links, sustainable and profitable practice change in agricultural systems cannot be achieved. A pilot project, in 2011-2012, with academic staff from three Australian universities identified vocational knowledge as a potential focus for a TLO. The AgLTAS project provides the opportunity to validate or refute this TLO by seeking input from a wider group of stakeholders, including industry. National consensus is being sought by a process of iterative consultation with academics, students and industry stakeholders and tested across four Australian universities. We have collected qualitative and quantitative data from industry participants who attended a series of workshops across most Australian States and Territories and through an online survey. Surprisingly, and contrary to the findings of the pilot project, industry representatives considered vocational knowledge of lesser importance to the need for students to attain highly developed problem solving and communication skills that can generate new opportunities and innovation in agriculture. Industryspecific(vocational) knowledge was generally regarded as attainable during on-the-job training after graduation. This finding prompts the question whether the AgLTAS Statement should be linked to professional accreditation that may be attaiined after graduation