Water relations of field-grown grapevines in the São Francisco Valley, Brazil, under different rootstocks and irrigation strategies

Abstract

There is an increased demand for high quality winegrapes in the São Francisco Valley, a new wine producing area in Brazil. As the grape quality is closely linked to the soil water status, understanding the effects of rootstock and irrigation management on grapevine water relations is essential to optimize yield and quality. This study was carried out to investigate the effects of irrigation strategies and rootstocks on water relations and scion vigour of field-grown grapevines in Petrolina, Pernambuco state, Brazil. The cultivars used as scions are Moscato Canelli and Syrah, both grafted onto IAC 572 and 1103 Paulsen rootstocks. The following water treatments were used: deficit irrigation, with holding water after veraison; and partial root-zone drying, supplying (100% of crop evapotranspiration) of the water loss to only one side of the root system after fruit set, alternating the sides periodically (about 24 days). In general, all treatments had values of pre-dawn leaf water potential higher than -0.2 MPa, suggesting absence of water stress. The vine water status was more affected by rootstock type than irrigation strategies. Both cultivars grafted on IAC 572 had the highest values of midday leaf water potential and stem water potential, measured on non-transpiring leaves, which were bagged with both plastic sheet and aluminum foil at least 1 h before measurements. For both cultivars, the stomatal conductance (g s ), transpiration (E) and leaf area index (LAI) were also more affected by roostsotck type than by irrigation strategies. The IAC 572 rootstock presented higher g s , E and LAI than the 1103 Paulsen. Differences in vegetative vigor of the scion grafted onto IAC 572 rootstocks were related to its higher leaf specific hydraulic conductance and deeper root system as compared to the 1103 Paulsen, which increased the water-extraction capability, resulting in a better vine water status. Key words: Vitis vinifera L., partial rootzone drying, deficit irrigation, stomatal conductance RELAÇÕES HÍDRICAS DE VIDEIRAS CULTIVADAS NO VALE DO SÃO FRANCISCO SOB DIFERENTES PORTA-ENXERTOS E ESTRATÉGIAS DE IRRIGAÇÃORESUMO: Existe aumento na demanda por vinhos de alta qualidade no Vale do São Francisco, nova região produtora de vinhos no Brasil. Como a qualidade da uva depende do estado hídrico da videira, o conhecimento dos efeitos do porta-enxerto e do manejo de irrigação sobre as relações hídricas da videira é essencial para otimizar a produção e qualidade da uva. Sendo assim, avaliou-se a influência de porta-enxertos e estratégias de irrigação sobre as relações hídricas e o vigor vegetativo de videiras cultivadas em Petrolina, PE. Duas variedades copa, 'Moscato Canelli' e 'Syrah', enxertadas sobre IAC 572 e 1103 Paulsen foram submetidas a duas estratégias de irrigação: irrigação com deficit, na qual a irrigação foi suspensa após o início da maturação; e irrigação parcial das raízes, em que a água foi aplicada (100% da evapotranspiração da cultura) após o pegamento dos frutos, em apenas metade do sistema radic...

A comparison of numerical and machine-learning modeling of soil water content with limited input data

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Cabernet Sauvignon grapevine grafted onto rootstocks during the autumn-winter season in southeastern Brazilian

“…Although the mechanism for grapevine scion vigor controlled by rootstocks is poorly understood, several authors have shown effects on water relations (Souza et al, 2009), gas exchange (Soar et al, 2006), vegetative vigor (Keller et al, 2001), yield and grape quality (Nuzzo and Mathews, 2006). Therefore, the selection of an appropriate rootstock may provide a powerful tool for managing the growth and fruiting of grapevine scions subjected to the double pruning technique.…”

Rootstock control of scion response to water stress in grapevine

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