Transpiration rates of eight-year-old mango 'Nam Dok Mai Si Thong' in well-watered conditions

T. Adultithipat, S. Isarangkool Na Ayutthaya, S. Meetha, R. Nampila
The optimal water supply to a plant is based on its requirement. This research investigates the transpiration rates of the mango cultivar 'Nam Dok Mai Si Thong' for an irrigation regime based on compensation of water loss by transpiration. The experiment was conducted on eight-year-old mangoes planted on a farmer's property located in the Ban-Had District, Khon Kaen Province, Thailand. Characteristics of the four-tree experimental were 3.5-4.0 m canopy width and 31.5-36.9 cm trunk girth. The xylem sap flux density was measured by xylem sap flow, using the transient thermal dissipation (TTD) method. Sap flow probes were inserted into the trunk at 60 cm above the soil level. The data collected by a CR1000 data logger every 30 min, as was the soil water status and climate data. The investigation took place from April to August 2019. The soil water status results showed well-watered conditions with a volumetric soil water content greater than 0.18 m3 m‑3. The daily sap flux density ranged from 24 to 37 L dm‑2 h‑1. The tree transpiration calculation rates were 20-32 L tree‑1 d‑1. A relationship between vapor pressure deficit (VPD) and water loss exhibited a plateau correlation. This occurred when the average daily VPD and maximum VPD ranges were 0.43-2.84 and 1.37-5.98 kPa, respectively. Results suggest that mango transpiration is regulated by extreme air evaporative demand conditions and the potential value of water supply for eight-year-old mangoes should be roughly 32 L tree‑1 d‑1.
Adultithipat, T., Isarangkool Na Ayutthaya, S., Meetha, S. and Nampila, R. (2021). Transpiration rates of eight-year-old mango 'Nam Dok Mai Si Thong' in well-watered conditions. Acta Hortic. 1312, 189-196
DOI: 10.17660/ActaHortic.2021.1312.28
xylem sap flux density, soil water content, vapor pressure deficit

Acta Horticulturae