THE ROLE OF MINERAL NUTRITION ON YIELDS AND FRUIT QUALITY IN GRAPEVINE, PEAR AND APPLE

ABSTRACT Fertilization of temperate fruit trees, such as grapevine ( Vitis spp.), apple ( Malus domestica), and pear ( Pyrus communis) is an important tool to achive maximum yield and fruit quality. Fertilizers are provided when soil fertility does not allow trees to express their genetic potential, and time and rate of application should be scheduled to promote fruit quality. Grapevine berries, must and wine quality are affected principally by N, that regulate the synthesis of some important compounds, such as anthocyanins, which are responsible for coloring of the must and the wine. Fermenation of the must may stop in grapes with low concentration of N because N is requested in high amount by yeasts. An N excess may increase the pulp to peel ratio, diluting the concentration of anthocyanins and promoting the migration of anthocyanins from berries to the growing plant organs; a decrease of grape juice soluble solid concentration is also expected because of an increase in vegetative growth. Potassium is also important for wine quality contributing to adequate berry maturation, concentration of sugars, synthesis of phenols and the regulation of pH and acidity. In apple and pear, Ca and K are important for fruit quality and storage. Potassium is the most important component of fruit, however, any excess should be avoided and an adequate K:Ca balance should be achieved. Adequate concentration of Ca in the fruit prevents pre- and post-harvest fruit disorders and, at the same time, increases tolerance to pathogens. Although N promotes adequate growth soil N availability should be monitored to avoid excessive N uptake that may decrease fruit skin color and storability

Towards theorising assessment as critical inquiry

Throughout the past two decades assessment has operated on two fronts. First has been the continuing interest in large-scale, standardised testing, which affords governments and countries data for accountability and reporting purposes. Second has been the increasing interest in assessment within a learning culture (Shepard, 2000). Broadly speaking, this has concentrated on formative assessment for improving learning and has generated a proliferation of phrases seeking to highlight vital connections between assessment and learning (for example, 'assessment for/as learning'). Each of these fronts can be understood as giving priority to particular assessment activities and contexts. In the case of standardised testing, usually undertaken to generate data for systems' purposes, the context is necessarily controlled, with variables such as time and place fixed and regulated.Arts, Education & Law Group, School of Education and Professional StudiesFull Tex