Similar drought avoidance and contrasting tolerance and recovery capacity across zoysiagrass cultivars: insights from controlled and field droughts

Improvements in water use efficiency and drought resistance in turfgrasses can help them maintain performance and quality with reduced irrigation, thereby contributing to water conservation. This study aimed to better understand the importance of drought avoidance, tolerance, and recovery from drought across three economically important cultivars of zoysiagrass and a newly released zoysiagrass cultivar with increased drought resistance. Experiments were performed under controlled conditions using long pots (30 cm deep) and in the field. Results from the controlled drought demonstrate that Lobo, Zeon, Empire, and Meyer have similar drought avoidance. The similar drought avoidance between Lobo and Zeon was also confirmed under natural droughts at two field locations. Tolerance and recovery from drought differed across cultivars. Lobo displayed greater tolerance than Zeon, Empire, and Meyer under controlled drought conditions. The greater tolerance of Lobo over Zeon was consistent with results from field droughts. Under controlled drought, Lobo and Meyer had greater recovery capacity than Zeon and Empire, and under field droughts, Lobo also had greater recovery than Zeon. While most studies show differences in water use across zoysiagrass lines and cultivars, contrasting drought tolerance and recovery capacity were identified in this study. The present findings indicate that drought avoidance, tolerance, and recovery capacity in zoysiagrass are independent of one another, which opens the possibility of achieving all three simultaneously through breeding efforts. For that, selection methods need to account for the three strategies, preferably at the field level or under controlled conditions using long pots.