Comparison of Three Different Fertigation Strategies for Drip Irrigated Table Grapes - Part I. Soil Water Status, Root System Characteristics and Plant Water Status

Ca. 260 mm for weekly irrigation. Root structures of grapevines irrigated by means of daily pulses had adapted by forming extremely dense root systems in the small wetted bulbs compared to the less frequently irrigated grapevines. Monitoring diurnal grapevine water status revealed that the different fertigation strategies did not affect water constraints up to veraison. During berry ripening, daily pulse irrigated grapevines experienced less water constraints in the morning, late afternoon and during the night than less frequently irrigated ones. However, the grapevines did not experience any detrimental water constraints throughout the season, irrespective of fertigation and irrigation frequencies or crop load. It was evident that grapevine water status not only depends on the size of the root structure, but also on the soil environment in which the roots function.