@Article{phyton.2022.023437,
AUTHOR = {Qingmin Pan, Yongzong Lu, Liang Xue, Yongguang Hu},
TITLE = {Leaf Wettability Difference Among Tea Leaf Ages and Analysis Based on Microscopic Surface Features},
JOURNAL = {Phyton-International Journal of Experimental Botany},
VOLUME = {92},
YEAR = {2023},
NUMBER = {2},
PAGES = {411--421},
URL = {http://www.techscience.com/phyton/v92n2/50130},
ISSN = {1851-5657},
ABSTRACT = {The wettability of leaf surface, commonly represented by contact angle (CA), affects various physiological and
physical processes. The present study aims to better understand the wettability of tea leaves and elucidate its influence on the energy barrier of the droplet condensation process. The CA values of different leaf ages (young,
mature and old) of five famous tea cultivars (<i>Maolu</i>, <i>longjing 43</i>, <i>Huangjinya</i>, <i>Zhongcha 108</i> and <i>Anji Baicha</i>)
were measured via the sessile drop method, and the micro-morphology of two cultivars leaves (<i>Maolu</i>, <i>Zhongcha
108</i>) was investigated by a 3D super depth-of-field digital microscope. Specifically, two radically distinctive types
of CA trends were observed, one was the decreased firstly and then increased slightly with the increase of leaf age,
while the other stayed constant. The valley depth or maximum height (R<sub>Z</sub>) of <i>Maolu</i> leaf surface increased with
the leaf age while the R<sub>Z</sub> of <i>Zhongcha 108</i> leaf remained unchanged by comparing the microscopic features. The
Maolu mature leaf CA decline attributed to the young leaf was hydrophilic (<i>θ</i> < 90°), and it was considered that
surface structures like folds and pits on old leaf played a crucial role in making CA increased. Small deviation in
CA can lead to significant error in calculation of the contact angle function of energy barrier in phase change. It
will have great significant for simulating and better understanding the formation of frost on tea leaves.},
DOI = {10.32604/phyton.2022.023437}
}