Moisture sensor-based irrigation enables the precise application of specific water availability conditions in the growing substrate, by adjusting irrigation scheduling according to actual moisture fluctuations within the root zone. This approach can be used to apply controlled water stress to plants. This study, consisting of two experiments across spring and autumn seasons, assessed the effects of different irrigation set-points on purple basil growth, physiological, and nutraceutical traits. Treatments were 0.40, 0.30, and 0.24 m3 m 3 in both seasons, with the addition of 0.50 m3 m 3 in autumn. At the lowest Volumetric Water Content (VWC), shoot and leaf fresh weight and leaf area decreased by 43%, 39%, and 37% in the spring and by 23%, 22%, and 17% in the autumn, while irrigation water productivity increased by 30% and 39%, respectively. In the spring, VWC 0.24 resulted in the lowest leaf water potential and Ca, K, and Cl content, but the highest NO3 content, while treatments had no effects on those parameters in autumn. The highest lipophilic antioxidant activity was observed at VWC 0.30 in the spring, while hydrophilic components were not influenced by treatments. VWC 0.24 more than doubled individual phenolic compounds in both seasons. Alpha tocopherol content followed similar trends, while carotenoids increased under controlled stress only in the spring. Stress effects were more pronounced during the spring season due to higher vapor pressure deficit (up to 2.4 kPa). This study demonstrates that sensor-based water stress control optimizes water use and enhances nutraceutical quality. Effects of different irrigation setpoints on plant water availability should be assessed not only in relation to soil moisture level but also to evapotranspirative demand.
Enhancing purple basil’s bioactive compounds with soil moisture sensor-controlled irrigation
Bonelli, Lucia;Montesano, Francesco Fabiano;Durante, Miriana;Serio, Francesco;D'Imperio, Massimiliano
2026
Abstract
Moisture sensor-based irrigation enables the precise application of specific water availability conditions in the growing substrate, by adjusting irrigation scheduling according to actual moisture fluctuations within the root zone. This approach can be used to apply controlled water stress to plants. This study, consisting of two experiments across spring and autumn seasons, assessed the effects of different irrigation set-points on purple basil growth, physiological, and nutraceutical traits. Treatments were 0.40, 0.30, and 0.24 m3 m 3 in both seasons, with the addition of 0.50 m3 m 3 in autumn. At the lowest Volumetric Water Content (VWC), shoot and leaf fresh weight and leaf area decreased by 43%, 39%, and 37% in the spring and by 23%, 22%, and 17% in the autumn, while irrigation water productivity increased by 30% and 39%, respectively. In the spring, VWC 0.24 resulted in the lowest leaf water potential and Ca, K, and Cl content, but the highest NO3 content, while treatments had no effects on those parameters in autumn. The highest lipophilic antioxidant activity was observed at VWC 0.30 in the spring, while hydrophilic components were not influenced by treatments. VWC 0.24 more than doubled individual phenolic compounds in both seasons. Alpha tocopherol content followed similar trends, while carotenoids increased under controlled stress only in the spring. Stress effects were more pronounced during the spring season due to higher vapor pressure deficit (up to 2.4 kPa). This study demonstrates that sensor-based water stress control optimizes water use and enhances nutraceutical quality. Effects of different irrigation setpoints on plant water availability should be assessed not only in relation to soil moisture level but also to evapotranspirative demand.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
