Gas exchange of field-grown "Vitis vinifera" L. cv. Zweigelt leaves in relation to leaf age and position along the stem

摘要: Aims: The study aimed to investigate the effects of leaf age and position along stem on seasonal evolution photosynthesis water use efficiency (WUE) primary leaves field-grown grapevines (Vitis vinifera L. cv. Zweigelt) under natural growing conditions in Pannonian climate.Methods results: Single-leaf gas exchange measurements were carried out three vineyards with different planting densities, training systems canopy management Neusiedlersee region (Burgenland, Austria). From beginning development until flowering, basal fruiting zone showed highest photosynthetic activity. After flowering ripening, activity continuously moved apical direction. Leaves reached their maximum 30 40 days after emergence, depending investigation site vineyard management. Due sufficient supply, old decreased slowly; thus 100 unfolding still retained 65% 75% activity.Conclusion: single-leaf Zweigelt grapevine corresponded results prior investigations other grape varieties. However, strongly influenced during period. from vines stressed by high crop load or poor early senescence a strong decline reaching level. Well-watered shoot-thinned moderate equal light exposure throughout exhibited much slower decrease older leaves.Significance impact study: indicate that favourable ensured adequate supply management, maintain good WUE over long period time. Thus leaves, as well, can contribute entire vine.