Strawberry production in tropical and subtropical climates has been adversely affected by rising temperatures and reduced cooling periods, leading to a decrease in flower induction and overall yield. This experiment aimed to investigate the effects of root zone cooling on short-day strawberry plants cultivated under evaporative greenhouse conditions. The cooling methods employed included of four root zone cooling treatments: normal water dripping (NWD), cold-water (10 °C) dripping (CWD), cold-water dripping plus cold-water pipe (CWD + CWP), and normal water dripping plus cold-water pipe (NWD + CWP) embedded within the growing media. The results indicated that the CWD + CWP treatment was particularly effective, reducing RZT by approximately 2 °C compared to other treatments, thereby promoting both vegetative and reproductive growth, particularly in the ‘Akihime’ strawberry. In the absence of root zone cooling, ‘Akihime’ and ‘Pharachatan 88’ were still capable of producing flowers and yield, whereas ‘Pharachatan 80’ was not. In addition, ‘Pharachatan 80’ was affected by CWD + CWP which showed the highest levels of total phenolic compound, total anthocyanin, and total vitamin C among all treatments. It can be concluded that reducing the root zone temperature through the integrated application of cold-water dripping and embedded cold-water pipes in the growing media can enhance the growth and development of short-day strawberry plants cultivated under evaporative greenhouse conditions in a tropical climate.

Strawberry production in tropical and subtropical climates has been adversely affected by rising temperatures and reduced cooling periods, leading to a decrease in flower induction and overall yield. This experiment aimed to investigate the effects of root zone cooling on short-day strawberry plants cultivated under evaporative greenhouse conditions. The cooling methods employed included of four root zone cooling treatments: normal water dripping (NWD), cold-water (10 °C) dripping (CWD), cold-water dripping plus cold-water pipe (CWD+CWP), and normal water dripping plus cold-water pipe (NWD+CWP) embedded within the growing media. The results indicated that the CWD+CWP treatment being particularly effective, reducing RZT by approximately 2 °C compared to other treatments. Thereby promoting both vegetative and reproductive growth, particularly in the ‘Akihime’ strawberry. In the absence of root zone cooling, ‘Akihime’ and ‘Pharachatan 88’ were still capable of producing flowers and yield, whereas ‘Pharachatan 80’ was no. In addition, ‘Pharachatan 80’ was affected by CWD+CWP which shown highest of total phenolic compound, total anthocyanin and total vitamin C among all treatments. It can be concluded that reducing the root zone temperature through the combined use of cold water dripping embedded cold-water pipe in the growing media can enhance the growth and development of short-day strawberry plants cultivated under evaporative greenhouse conditions in tropical climate.

The experiment was carried out during October 2022 to January 2023 at Mae Hea Agricultural Research, Demonstration and Training Center, Faculty of Agriculture, Chiang Mai University, Chiang Mai Province, Thailand; latitude: 18° 44′ 36″ North, Longitude: 98° 57′ 50″ East, and an al-titude 304 msl. Evaporative greenhouse, 9.6 x 40 square meters, with 8 planting troughs was prepared, Sensors and Internet of Things (IoT) system were installed to monitor continuously vital parameters, collect data, and send timely alerts to facilitate problem resolution. The data were displayed via IoT platform dashboard. An average air temperature, light intensity, media moisture and CO2 concentration in the greenhouse during 4 months was 21.1 ◦C, 12,948 Lux, 2 kPa and 495 ppm, respectively. The average maximum temperature in the evaporative greenhouse was 29.6 ◦C, which 4.2 ◦C lower than outside; 33.8 ◦C. Root-zone cooling of the strawberry planting was de-signed as factorial 3x4 in completely randomized design (CRD). Factor A was the short-day strawberry cultivars: 1) “Pharachatan 88” 2) “Pharachatan 80” and 3) “Akihime”. Factor B was the root-zone cooling treatments: 1) normal water dripping (NWD) 2) cold water dripping (CWD) 3) cold water dripping + cold water piping (CWD+CWP) and 4) normal water dripping + cold water piping (NWD+CWP). The results revealed that there was an interaction between the two factors on canopy width, leave width, crown diameter, number of flowers, fruit qualities and fruit color, whereas plant height, leaves length, SPAD and number of inflorescences were not affected by the interaction between the two factors. Four months after the experiment, the root-zone cooling treatments had no effect on chlorophyll contents, whereas “Pharachatan 80” had lower chlorophyll content than others. The CWD+CWP treatment could reduce 2 °C of root-zone temperature and leading to promote vegetative and reproductive growth in strawberry plants. Anyhow, without the root-zone cooling treatment, “Akihime”and “Pharachatan 88” still could produce flowers and yield, but “Pharachatan 80” could not. Furthermore, “Akihime” seemed appreciable in flowering, TSS and yield as compared to others.