Erosion of Waxes From Leaf Surfaces by Simulated Rain

Abstract

SUMMARYEffects of simulated rain on the epicuticular wax of glaucous leaves have been studied. Droplets (250 to 400 fim) travelling at low or medium velocity (0 25 to 5 m s'^) fractured the dendrites and tubes on leaves of Brassica spp., the tubes on Eucalyptus globulus Labillardere and the ribbons on the adaxial surfaces of Pisum sativum L. and Fragaria ananassa Duchesne. Rates of erosion for Brassica and E. globulus leaves were high during an initial application equivalent to 1 mm rainfall but declined markedly with extended exposure. In contrast, erosion from P. sativum and F. ananassa proceeded at a fairly uniform rate throughout the exposure period. The composition of the detached wax deposits was identical with that of the intact leaf wax for Brassica species but differed for the other species. The practical consequences of wax erosion of field crops are considered.

Variability in the Wettability and Water Storage Capacity of Common Oak Leaves (Quercus robur L.)

“…In September, along with the analogous increase in mildew cover on leaves, the S values grew from 11% to 25%. Therefore, we can see a distinct influence of leaf age, i.e., the month when a sample was collected for analysis [45].…”

Proceedings of the coast redwood forests in a changing California: A symposium for scientists and managers

“…Specifically for P. munitum, the greatest foliar uptake capacity was observed at the Grove of Old Trees, the windiest and foggiest site studied. Both wind and fog abrade the cuticle (Baker and Hunt 1986, Hoad et al 1992, Pitcairn et al 1986) and may have resulted in greater capacity of P. munitum to absorb water directly through its fronds in this forest.…”

The effects of dry O3, SO2 and NO2 on reconstituted epicuticular wax tubules

“…Various hypotheses for the explanation of the phenomenon may be put forward: (1) inorganic gases not covered in this study (e.g. NjO or NO) or mixtures of air pollutants might react directly with nonacosan-10-ol (Huttunen & Laine, 1981;Cape, 1983); (2) direct reactions might be accelerated in the presence of water (Percy & Baker, 1990;Turunen & Huttunen, 1991); (3) nonacosan-10-ol might be sensitive to intermediates formed in reactions of inorganic air pollutants either with plant products like diterpenoids (Elstner, Osswald & Youngman, 1985) or with airborne organic xenobiotics like polycyclic aromatic hydrocarbons (Aceves & Grimalt, 1993); (4) tubules might be destroyed or even eroded by the mechanical impact of dust or precipitation (Baker & Hunt, 1986;Gunthardt-Goerg, 1991). These hypotheses, which imply the direct action of atmospheric conditions on epicuticular crystals, have not yet been tested experimentally.…”