Blanco Victor, Kalcsits Lee
Department of Horticulture, Washington State University, Pullman, WA, United States.
Efficient Use of Water in Agriculture Program, Institute of Agrifood Research and Technology (IRTA), Lleida, Spain.
Front Plant Sci. 2024 May 24;15:1393028. doi: 10.3389/fpls.2024.1393028. eCollection 2024.
Instrumentation plays a key role in modern horticulture. Thus, the microtensiomenter, a new plant-based sensor that continuously monitors trunk water potential (Ψ) can help in irrigation management decisions. To compare the response of the Ψ with other continuous tree water status indicators such as the sap flow rate, the difference between canopy and air temperatures, or the variations of the trunk and fruit diameter, all the sensors were installed in 2022 in a commercial orchard of 'Honeycrisp' apple trees with M.9 rootstocks in Washinton State (USA). From the daily evolution of the Ψ, five indicators were considered: predawn, midday, minimum, daily mean, and daily range (the difference between the daily maximum and minimum values). The daily range of Ψ was the most linked to the maximum daily shrinkage (MDS; R = 0.42), the canopy-to-air temperature (Tc-Ta; R = 0.32), and the sap flow rate (SF; R = 0.30). On the other hand, the relative fruit growth rate (FRGR) was more related to the minimum Ψ (R = 0.33) and the daily mean Ψ (R = 0.32) than to the daily range of Ψ. All indicators derived from Ψ identified changes in tree water status after each irrigation event and had low coefficients of variation and high sensitivity. These results encourage Ψ as a promising candidate for continuous monitoring of tree water status, however, more research is needed to better relate these measures with other widely studied plant-based indicators and identify good combinations of sensors and threshold values.
仪器在现代园艺中起着关键作用。因此，微型张力计这种新型的基于植物的传感器能够持续监测树干水势（Ψ），有助于做出灌溉管理决策。为了比较Ψ与其他连续的树木水分状况指标（如液流速率、冠层与空气温度之差或树干和果实直径的变化）的响应情况，2022年在美国华盛顿州一个种植M.9砧木的‘蜜脆’苹果树的商业果园中安装了所有传感器。根据Ψ的每日变化，考虑了五个指标：黎明前、中午、最小值、日均值和日变化范围（日最大值与最小值之差）。Ψ的日变化范围与最大日收缩量（MDS；R = 0.42）、冠层与空气温度之差（Tc - Ta；R = 0.32）以及液流速率（SF；R = 0.30）的相关性最强。另一方面，相对果实生长速率（FRGR）与最小Ψ（R = 0.33）和日平均Ψ（R = 0.32）的相关性比与Ψ的日变化范围的相关性更强。所有从Ψ得出的指标都能识别每次灌溉事件后树木水分状况的变化，并且变异系数低、灵敏度高。这些结果表明Ψ有望成为持续监测树木水分状况的候选指标，然而，还需要更多研究来更好地将这些指标与其他广泛研究的基于植物的指标联系起来，并确定传感器和阈值的良好组合。
