Analysis of physiological adaptive mechanisms developed by grapevines to deal with environmental adversities is of prime strategy to maintain more efficient viticulture. In this context, certain exogenous treatments have been tested for effectiveness on enhancement of the grapevine growth against to constraints such as climatic extremes among which drought and high temperature predominate. Iron and micronized calcite pulverizations were performed three times during the vegetation period to soilless grown five years old grapevines of ‘Italia’ cultivar in controlled glasshouse in order to assess their possible effects on certain physiological and agronomic features of the vines imposed to mild stress condition of elevated air temperature (with midday means around 37.5±5.6 5 °C), decreased humidity in both air and growth substrate. Fe treatment increased the stomatal conductance in the hottest period of the experiment. The treatments did not affect the leaf temperature, while the chlorophyll and relative water contents of the leaves were improved by all the applications. The leaf mass and pruning residue measurements revealed that the individual application of Fe or calcite induced the vegetative development of the vines. Fe pulverization, with calcite in particular, remarkably increased the cluster mass and the size, although the biochemical features of the must were not affected by the treatments. Therefore, the use of Fe chelates supplemented with micronized calcite would be recommended to enhance grapevine development and grape quality on the face of ever-increasing global warming incidence.
Table grapes, climate extremes, vine physiology, grape quality