A Proposed Method for Simultaneous Measurement of Cuticular Transpiration From Different Leaf Surfaces in Camellia sinensis

Plasticity of the Cuticular Transpiration Barrier in Response to Water Shortage and Resupply in Camellia sinensis: A Role of Cuticular Waxes

“…Next, the wax chemical classes were examined. The tea leaf cuticular waxes include acids, aldehydes, 1-alkanols, alkanes, 1-alkanol esters, glycol esters, phthalate esters, glycols, β-tocopherol, triterpenoids, steroids, caffeine, and some unknown components ( Kulkarni et al, 2018 ; Zhu et al, 2018 ; Zhang et al, 2020 ). The majority of the chemical classes from adaxial EWs of 0202-10 and 0306A were significantly increased by WD treatment ( Figure 2A , middle and lower panels); in contrast, most of these chemical classes from Wuniuzao were not affected by WD treatment – some waxes were even reduced by WD treatment ( Figure 2A , upper panel).…”

“…The cuticular transpiration rates from the detached 5th leaf were measured from WW control, day 8 of WD (D8), and day 10 of rehydration (RE) as the methods of Zhang et al (2020) . Briefly, shoots with one bud and seven leaves were removed, and the cutting end of the shoots were immersed in water and equilibrated overnight.…”

“…Epicuticular waxes and IWs were isolated from the 5th leaf of WW control, day 8 of WD, and day 10 of RE as Zhang et al (2020) . Delipidated gum arabic was dissolved in water to a final concentration of 90% (w/v), and aqueous solution was evenly applied to leaf surface to form a film.…”

“…The establishment of an efficient isolation method to differentiate EWs from IWs necessitates a differential analysis of the cuticular transpiration barrier and its relationship with cuticular composition. These studies demonstrated that the adaxial IWs and abaxial EWs constitute major cuticular transpiration barrier, while the adaxial EWs and abaxial IWs are not major contributors to leaf transpiration barrier ( Vogg et al, 2004 ; Buschhaus et al, 2015 ; Jetter and Riederer, 2016 ; Zhang et al, 2020 ). Aliphatic compounds from adaxial IWs are correlated mainly with cuticular transpiration barrier ( Jetter and Riederer, 2016 ), while the alicyclic compounds did not contribute to cuticular transpiration barrier ( Buschhaus and Jetter, 2012 ).…”

“…Consistent with this conclusion, the permeation of active ingredients is limited by very long-chain aliphatic compounds rather than alicyclic wax compounds ( Staiger et al, 2019 ). Recently, we demonstrated that abaxial cuticle showed different transpiration barrier organization from its adaxial counterpart: the abaxial EWs is another major transpiration barrier while the abaxial IWs contribute minorly ( Zhang et al, 2020 ). Adaxial IWs showed higher coverage in very long chain fatty acids (VLCFAs), 1-alkanol esters, and glycols than that of abaxial IWs, suggesting that these waxes could contribute to their differential barrier properties under normal growth conditions ( Zhang et al, 2020 ).…”