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Janova, J.

Publications and source records attributed to Janova, J..

2 recordsLinked to original sources

Removal of epicuticular wax has no effect on the rate of cuticular wax deposition, which is constant in mature cherry laurel leaves

O_LIThe plant cuticle, multifunctional hydrophobic air-to-plant boundary, vary dramatically among plant species and responds dynamically to environmental and biotic factors. These dynamics, certainly driven by cost-benefit selection, are poorly understood up to now. C_LIO_LI13C labelling and compound-specific isotope analysis open a new avenue to study the cuticle dynamics. We studied side specific leaf cuticular wax regeneration, in different compounds, and separately for intra-(IW) and epicuticular wax (EW), as well as the effect of epicuticular wax removal on the regeneration rate. C_LIO_LIMature leaves that reached the final area before the start of the experiment deposited new IW at first, but quickly equilibrated with EW. Removal of EW accelerated this equilibration but not the net rate of new wax deposition. The n-alkanes had the fastest turnover. Pentacyclic triterpenoids (ursolic acid) had a surprisingly slow turnover due to the large pool but also slow deposition rate. Adaxial and abaxial leaf surfaces exhibited small but consistent differences. C_LIO_LIWe demonstrated for the first time that EW removal does not affect wax deposition rate in evergreen leaf cuticle. We also confirmed that collodion discriminates between EW and IW well and does not inhibit future leaf metabolism and wax deposition in our species. C_LI

plant biology↗

Cuticular wax, but not the cutin matrix, is renewed during the lifespan of Clusia rosea leaves13CO2 labelling and gas exchange study

O_LIThe plant cuticle, which aided the water-to-land transition of plants, provides various services to the plant surface, and its synthesis and maintenance represent substantial metabolic costs. Nevertheless, only limited information regarding cuticle dynamics is available. C_LIO_LIWe determined the composition and dynamics of Clusia rosea cuticular waxes and matrix using 13CO2 labelling, compound-specific and bulk isotope ratio mass spectrometry. Collodion was used for wax collection; gas exchange techniques were employed to test for any collodion effects on living leaves. C_LIO_LICutin matrix (MX) area density did not vary between young and mature leaves and between leaf sides. Only young leaves incorporated new carbon into their MX. Collodion-based sampling discriminated between epicuticular (EW) and intracuticular wax (IW) effectively. EW differed in composition from IW. The newly synthetized wax was deposited in IW first and later in EW. Both young and mature leaves synthetized IW and EW; the faster dynamics in young leaves was not due to a faster synthesis rate but was the result of lower wax coverage. Longer-chain alkanes were deposited preferentially on the abaxial, stomatous leaf side, producing differences between leaf sides in wax composition. C_LIO_LIWe introduce a new, sensitive isotope labelling method and demonstrate that cuticular wax is renewed during leaf ontogeny of Clusia rosea. We discuss the ecophysiological significance of the new insights. C_LI

plant biology↗