Wax Composition Research Articles

Performance analysis of photovoltaic module using eutectic phase change material

ABSTRACT Geographical factors and environmental variables affect the performance of the solar photovoltaic (SPV) system. The incident solar radiation on the SPV will generate power and increase the surface temperature. Thermal regulation is needed for the SPV system to enhance its performance. In this work, a passive cooling approach is adopted to reduce the surface temperature of the SPV system. The eutectic phase change material is synthesized with the composition of RT35 paraffin wax and sodium sulfate decahydrate. The thermophysical properties of the eutectic mixture are analyzed using a differential scanning calorimeter, and thermal conductivity is measured. The developed eutectic PCM is integrated into the SPV modules’ rear-side packing in the aluminum container. The output of the PV module is increased by 10% and up to 6.1°C reduces the surface temperature of the SPV module compared to the conventional SPV system.

Characterization of morphological and chemical changes using atomic force microscopy and metabolism assays: the relationship between surface wax and skin greasiness in apple fruit.

Skin greasiness occurred on stored apples (Malus domestica Borkh.) is generally believed to result from changes in surface wax components. Previous reports have typically correlated wax changes with greasiness scores to reveal the contributing wax components. A notable limitation of this approach is that greasiness scores are highly subjective and influenced by individual perception. This study aimed to assess skin quality by quantitatively analyzing wax morphology changes in greasy 'Jonagold' apples using Atomic Force Microscopy (AFM) roughness parameters Ra, Rq, Rmax, and Rz, and to correlate these changes with wax composition. AFM results revealed that wax crystals disappeared as skin greasiness increased, accompanied by significant declines in roughness parameters Ra, Rq, Rmax, and Rz, which decreased by 70% to 85%. Chemical analysis showed a significant increase in liquid esters, including linoleate and oleate esters, in the surface waxes, which negatively correlated with the decline in roughness parameters. Key genes related to ester production, such as MdFAD2, MdWSD1, and MdWBC11, exhibited increased expression and were also negatively correlated with decreases in Rq, Ra and Rz. Additionally, 1-Methylcyclopropene (1-MCP) treatment suppressed both the development of greasiness and the associated changes. Our findings suggest that the increased liquid esters contribute to alternations in wax morphology in greasy apples, and that MdFAD2, MdWSD1, and MdWBC11, play crucial roles in ester biosynthesis. These results highlight the effectiveness of AFM roughness parameters Ra, Rq, Rmax, and Rz in quantifying wax morphology changes in apples during skin greasiness development.

Development and characterisation of myristic acid-paraffin wax, silica fume and zinc oxide cementitious composites for thermal control in buildings

This study focuses on the development of a cement-based phase change material (CBPCM) to improve thermal performance in construction applications. The CBPCM was synthesised by blending 90 wt% of myristic acid with 10 wt% of paraffin wax, absorbed into 10 wt% of silica fume to prevent leakage. Additionally, 5 wt% of zinc oxide was added to improve thermal conductivity. A leakage test conducted with 10 wt% of SF exhibited no signs of leakage during thermal cycling. Scanning electron microscopy (SEM) established the uniform dispersion of the nano-enhanced phase change material (NEPCM) within the cement. Fourier transform infrared spectroscopy (FTIR) analysis revealed no chemical structure changes after 100 thermal cycles. Thermogravimetric analysis (TGA) confirmed thermal stability in the temperature range of 74.8–236.64 °C with a mass loss of 6.3 wt%. The material demonstrated minimal variation in phase change temperatures and latent heats after 100 cycles. The latent heat of the CBPCM was 1.09 J/g during melting and 1.887 J/g during solidification. Incorporating NEPCM into the cement increased the thermal conductivity of the cement matrix to 0.559 W/m K. These findings underline the potential of the CBPCM for energy-efficient construction, offering enhanced thermal storage, stability, and conductivity.

Integrative multi-omic analysis identifies genes associated with cuticular wax biogenesis in adult maize leaves.

Studying the genetic basis of leaf wax composition and its correlation with leaf cuticular conductance (gc) is crucial for improving crop productivity. The leaf cuticle, which comprises a cutin matrix and various waxes, functions as an extracellular hydrophobic layer, protecting against water loss upon stomatal closure. To address the limited understanding of genes associated with the natural variation of adult leaf cuticular waxes and their connection to gc, we conducted statistical genetic analyses using leaf transcriptomic, metabolomic, and physiological data sets collected from a maize (Zea mays L.) panel of ∼300 inbred lines. Through a random forest analysis with 60 cuticular wax traits, it was shown that high molecular weight wax esters play an important role in predicting gc. Integrating results from genome-wide and transcriptome-wide studies (GWAS and TWAS) via a Fisher's combined test revealed 231 candidate genes detected by all three association tests. Among these, 11 genes exhibit known or predicted roles in cuticle-related processes. Throughout the genome, multiple hotspots consisting of GWAS signals for several traits from one or more wax classes were discovered, identifying four additional plausible candidate genes and providing insights into the genetic basis of correlated wax traits. Establishing a partially shared genetic architecture, we identified 35 genes for both gc and at least one wax trait, with four considered plausible candidates. Our study enhances the understanding of how adult leaf cuticle wax composition relates to gc and implicates both known and novel candidate genes as potential targets for optimizing productivity in maize.

Hydroclimatic change and vegetation response in Tropical African alpine environments over the Holocene

Future precipitation is highly uncertain, particularly in East Africa where model projections contradict modern observational trends. Climate changes in East Africa's mountains are even less well understood, yet these mountains are threatened by warming, extreme flooding, fires, and the rapid disappearance of glaciers. Paleoclimatic and paleoenvironmental records can contextualize ongoing and future changes; however, proxy records from East African mountains disagree with each other and, in some cases, differ from nearby lowland sites. It is unclear if these discrepancies are due to geographic or altitudinal gradients in climate or processes that impact the fidelity of climate proxies in these mountains. To better understand past mountain precipitation and vegetation change, we produced three new records of the hydrogen and carbon isotopic composition of terrestrial leaf waxes (δ2Hwax and δ13Cwax) spanning the Holocene using lake sediment cores collected from Lake Mahoma (2990 m asl), Lake Africa (3895 m asl), and Lake Kopello (4017 m asl) in the Rwenzori Mountains, Uganda-Democratic Republic of Congo. We find similar trends at all three sites in reconstructed precipitation hydrogen isotopic composition (δ2Hprecip), which we interpret to reflect precipitation amount. Our records show drying occurred during the Younger Dryas (∼12 cal ka BP), enhanced precipitation during the African Humid Period (∼10-5 cal ka BP) and drying in the mid to late Holocene (∼5-0 cal ka BP), similar to adjacent lowland sites. We observe a gradual termination of the African Humid Period in the Rwenzori, consistent with many regional records. We also observe distinct patterns of Holocene precipitation change in Eastern and Western Africa, indicating differences in the delivery of moisture from the Atlantic and Indian Oceans. Despite changes in precipitation over the Holocene, the carbon isotopic composition of the waxes in Rwenzori lakes indicates constant C3 vegetation and eco-hydrological stability, in contrast to sites from lower elevations. This likely indicates climate remained humid and cool enough throughout the Holocene to maintain forest and alpine plant communities at these high-elevation mountain sites.

EUPHORBIA CERIFERA CERA (CANDELILA) EMOLLIENT PROPERTIES, USES AND EFFECTIVENESS IN SKINCARE PRODUCTS

Candelila wax, derived from Euphorbia cerifera cera, is a natural and sustainable component that has a wide range of uses in cosmetic products. This review article explores the chemical composition, extraction techniques, and attributes of Candelila wax, with a focus on its distinctive qualities that make it highly useful in the cosmetic business. Candelila wax has been extensively studied and researched, and these studies have shown that it is highly useful in skincare. It has been found to provide significant benefits in terms of moisturizing the skin, protecting it, and improving the function of the skin barrier. The emollient and moisturizing qualities of this substance enhance skin hydration, while its film-forming capacity creates a protective barrier against environmental stresses. In addition, the non-comedogenic properties and potential anti-inflammatory effects of Candelila wax make it highly suitable for a range of skin types, including those that are sensitive or prone to acne. The future outlook for Candelila wax in cosmetics entails investigating the potential benefits of combining it with other natural substances, creating new and advanced methods of delivering it, and embracing sustainable methods of sourcing and processing. By conducting meticulously planned clinical trials, the effectiveness and safety of the substance may be verified, thereby establishing robust scientific proof for its use in skincare products. By recognizing the possibilities of Candelila wax, we may explore environmentally responsible and skin-conscious cosmetic procedures that align with the changing tastes of mindful customers. By utilizing the potent properties of this natural substance, the cosmetic industry can lead the path towards a more environmentally friendly and enduring future in the field of skincare products.

Composition and micromorphological determination of blue honeysuckle fruit (Lonicera caerulea L.) cuticular wax and its effects on fruit post-harvest quality

The chemical composition and structure of the cuticular wax in blue honeysuckle fruit were investigated using gas chromatography–mass spectrometry (GC–MS) and scanning electron microscopy (SEM). The results revealed that the cuticular wax was dense and uniform, taking on a tubular form. A total of 158 wax components were identified, including alkanes, terpenes, ketones, alcohols, fatty acids, and esters. The wax was found to be particularly rich in alkanes. After storage, the wax content decreased, whereas an increase in 1-undecanol. The destruction or reduction of cuticular wax resulted in a more rapid decline in storage quality, loss of nutrients, and a decrease in antioxidant phytochemicals. Meanwhile, wax metabolizing enzyme activity and gene expression increased. This study presents a deeper understanding of blue honeysuckle fruit cuticular wax composition and aids to developing effective measures to delay its postharvest fruit quality deterioration.

Effects of Different Shade Treatments on the Epidermal Wax Deposition of Hosta Genotypes with Different Glaucousness of Leaf Surface

Epidermal wax is strategically situated at the interface between plants and air; therefore, it plays a key role in plants’ interactions with their surroundings. It is also unstable and susceptible to light intensity. Hosta plants are shade-loving herbs with admirable flowers and leaves. Hosta ‘Halcyon’ and Hosta ensata F. Maek. are two species of Hosta with a glaucous and a glossy appearance, respectively. Light intensity can affect the composition of epicuticular wax on the leaf surface, which influences the leaf color phenotype and ornamental value. In this paper, the crystal micromorphology, content, and components of epicuticular wax on the leaves of two species of Hosta under different light conditions (10%-, 30%-, 50%-, 70%-, and 100%-intensity sunlight, relative light intensity (RLI)) have been studied using pot experiments. The results indicate that the epicuticular wax crystals of H. ‘Halcyon’ and H. ensata are tubular and platelet-like, respectively. The wax crystals of H. ‘Halcyon’ melted and formed a thick crust under 100% RLI, and those of H. ensata melted and formed a thick crust under 70% and 100% RLI conditions. The primary ingredients of the epicuticular wax of the two species of Hosta contained primary alcohols, alkanes, fatty acids, and esters; β-diketones were only detected in H. ‘Halcyon’. The quantity of epicuticular wax of H. ‘Halcyon’ reduced at first and then increased with an RLI increase, achieving its lowest value at 50% RLI, but that of H. ensata declined little by little. The amounts of C28 primary alcohols, C31 alkanes, and C18 fatty acids were significantly higher than those of other carbon atoms in the two genotypes of Hosta. The C31β-diketones content decreased with the increase in light intensity, which caused the white frost phenotype to gradually weaken in H. ‘Halcyon’.

Features of using SLA‑technology in the manufacture of molds for lost wax casting

The results of using SLA‑technology in the manufacture of molds for obtaining wax models in lost wax casting are presented. 3D printing modes of molds have been developed to ensure the required roughness of the working surfaces and durability of the resulting molds. The optimal parameters for pressing the wax composition into molds made using SLA technology have been established. It is shown that the use of SLA technology for the manufacture of molds makes it possible to obtain wax models and castings of the required quality. An experimental technology has been developed for the production of castings from bronze by casting according to smelted models.

First line of defence: Eucalyptus leaf waxes influence infection by an aggressive fungal leaf pathogen.

Leaf epicuticular waxes provide important anatomical and chemical defences against fungi that infect leaves. In this study we analysed the leaf wax composition of Eucalyptus grandis × Eucalyptus urophylla hybrids with contrasting susceptibilities to Teratosphaeria leaf blight (TLB) caused by Teratosphaeria destructans, one of the most important foliar diseases of Eucalyptus. The Eucalyptus cuticular wax was extracted from non-inoculated and inoculated genotypes with different levels of susceptibility to TLB and analysed by gas chromatography-mass spectrometry. The results showed that a triterpenoid, cycloartenol (CAS), was abundant in a resistant genotype and that hexanedioic acid content increased in the resistant genotypes in response to T. destructans infection. In contrast, palmitic acid was significantly more abundant in the inoculated highly susceptible genotype. In-vitro and in-planta T.destructans spore germination assays with pure compounds, showed that CAS and hexanedioic acid significantly inhibited spore germination. Application of these two compounds to the leaves of a susceptible host also significantly increased resistance to infection. In contrast, palmitic acid promoted spore germination and, when applied to the leaves of a resistant genotype, increased colonization by the pathogen. This is the first study providing insights into differences in the leaf wax composition of hosts with different levels of susceptibility to T. destructans. It also showed that leaf wax compounds can modulate spore germination and, ultimately, host resistance to infection.

Selective capture of PM2.5 by urban trees: The role of leaf wax composition and physiological traits in air quality enhancement

Human health risks from particles with a diameter of less than 2.5 µm (PM2.5) highlight the role of urban trees as bio-filters in air pollution control. However, whether the size and composition of particles captured by various tree species differ or not remain unclear. This study investigates how leaf attributes affect the capture of PM2.5, which can penetrate deep into the lungs and pose significant health risks. Using a self-developed particulate matter (PM) resuspension chamber and single-particle aerosol mass spectrometer, we measured the size distribution and mass spectra of particles captured by ten tree species. Notably, Cinnamomum camphora (L.) J.Presl and Osmanthus fragrans Lour. are more effective at capturing particles under 1 µm, which are most harmful because they can reach the alveoli, whereas Ginkgo biloba L. and Platanus × acerifolia (Aiton) Willd. tend to capture larger particles, up to 1.6 µm, which are prone to being trapped in the upper respiratory tract. Leaf physiological traits such as stomatal conductance and water potential significantly enhance the capture of larger particles. The Adaptive Resonance Theory neural network (ART-2a) algorithm classified a large number of single particles to determine their composition. Results indicate distinct inter-species variations in chemical composition of particles captured by leaves. Moreover, we identified how specific leaf wax compositions—beyond the known sticky nature of hydrophobic waxes—contribute to particle adhesion, particularly highlighting the roles of fatty acids and alkanes in adhering particles rich in organic carbon and heavy metals, respectively. This research advances our understanding by linking leaf physiological and wax characteristics to the selective capture of PM2.5, providing actionable insights for urban forestry management. The detailed exploration of particle size and composition, tied to specific tree species, enriches the current literature by quantifying how and why different species contribute variably to air quality improvement. This adds a crucial layer of specificity to the general knowledge that trees serve as bio-filters, offering a refined strategy for planting urban trees based on their particulate capture profiles.

Effect of light-induced changes in leaf anatomy on intercellular and cellular components of mesophyll resistance for CO2 in Fagus sylvatica.

Mesophyll resistance for CO2 diffusion (rm) is one of the main limitations for photosynthesis and plant growth. Breeding new varieties with lower rm requires knowledge of its distinct components. We tested new method for estimating the relative drawdowns of CO2 concentration (c) across hypostomatous leaves of Fagus sylvatica. This technique yields values of the ratio of the internal CO2 concentrations at the adaxial and abaxial leaf side, cd/cb, the drawdown in the intercellular air space (IAS), and intracellular drawdown between IAS and chloroplast stroma, cc/cbd. The method is based on carbon isotope composition of leaf dry matter and epicuticular wax isolated from upper and lower leaf sides. We investigated leaves from tree-canopy profile to analyse the effects of light and leaf anatomy on the drawdowns and partitioning of rm into its inter- (rIAS) and intracellular (rliq) components. Validity of the new method was tested by independent measurements of rm using conventional isotopic and gas exchange techniques. 73% of investigated leaves had adaxial epicuticular wax enriched in 13C compared to abaxial wax (by 0.50‰ on average), yielding 0.98 and 0.70 for average of cd/cb and cc/cbd, respectively. The rIAS to rliq proportion were 5.5:94.5% in sun-exposed and 14.8:85.2% in shaded leaves. cc dropped to less than half of the atmospheric value in the sunlit and to about two-thirds of it in shaded leaves. This method shows that rIAS is minor but not negligible part of rm and reflects leaf anatomy traits, i.e. leaf mass per area and thickness.

Physiological characterization of the tomato cutin mutant cd1 under salinity and nitrogen stress.

We identified tomato leaf cuticle and root suberin monomers that play a role in the response to nitrogen deficiency and salinity stress and discuss their potential agronomic value for breeding. The plant cuticle plays a key role in plant-water relations, and cuticle's agronomic value in plant breeding programs is currently under investigation. In this study, the tomato cutin mutant cd1, with altered fruit cuticle, was physiologically characterized under two nitrogen treatments and three salinity levels. We evaluated leaf wax and cutin load and composition, root suberin, stomatal conductance, photosynthetic rate, partial factor productivity from applied N, flower and fruit number, fruit size and cuticular transpiration, and shoot and root biomass. Both nitrogen and salinity treatments altered leaf cuticle and root suberin composition, regardless of genotype (cd1 or M82). Compared with M82, the cd1 mutant showed lower shoot biomass and reduced partial factor productivity from applied N under all treatments. Under N depletion, cd1 showed altered leaf wax composition, but was comparable to the WT under sufficient N. Under salt treatment, cd1 showed an increase in leaf wax and cutin monomers. Root suberin content of cd1 was lower than M82 under control conditions but comparable under higher salinity levels. The tomato mutant cd1 had a higher fruit cuticular transpiration rate, and lower fruit surface area compared to M82. These results show that the cd1 mutation has complex effects on plant physiology, and growth and development beyond cutin deficiency, and offer new insights on the potential agronomic value of leaf cuticle and root suberin for tomato breeding.

Synergistic Effects of Heated Walnut Shell Powder and Reduced Graphene Oxide in Paraffin Wax Composites for Marine Thermal Applications

The study focuses on creating and analyzing paraffin wax composites enriched with heated walnut shell powder and reduced graphene oxide nanoparticles. Experimental procedures include careful blending of materials to form homogeneous mixtures, followed by analysis using techniques such as thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). The composites show improved thermal properties compared to pure paraffin wax, with increased melting temperatures, heat of fusion, and thermal conductivity. The study also examines density and thermal diffusivity, providing insights into thermal behavior. Additionally, it ensures the corrosion resistance of nano-enhanced bio-based phase change materials (PCMs) for marine engineering through thorough material selection, corrosion testing, and long-term exposure studies simulating seawater conditions. The study evaluates environmental impacts, toxicity, and compliance with standards and proposes mitigation strategies like protective coatings and encapsulation techniques. Overall, the research contributes to developing environmentally sustainable PCM materials for marine applications and offers insights into their thermal behavior for thermal energy storage and management.

Exploring the Impact of Silane Surface Modification on ZnO nanoparticles in the Wettability of PLA/Natural Wax Composites

Exploring the Impact of Silane Surface Modification on ZnO nanoparticles in the Wettability of PLA/Natural Wax Composites

Lupeol a predisposing factor in grey mould (Amphobotrys ricini [N.F. Buchw.]) Hennebert disease pathogenesis in castor (Ricinus communis L.)

AbstractTo understand the castor wax layer's multifaceted contribution to Amphobotrys ricini pathogenesis, the hydrophobic components of cuticular wax were analysed from waxy and non‐waxy castor genotypes. Gas chromatography–mass spectrometry (GC–MS) technology enabled the stable detection and quantitative determination of various fatty acids and terpenoids. The investigation revealed a significant presence of triterpenoid compound ‘lupeol’, accounting for approximately 53.6% of the wax composition in the waxy genotype (DCH‐519), which was absent in non‐waxy genotype (ICS‐324). On exposure to lupeol, about 93.3% of conidia germinated leading to rapid mycelium growth and sporulation of A. ricini. SEM analysis of waxy and non‐waxy genotypes infected with A. ricini confirmed faster germination and production of longer germ tubes on waxy genotype compared with non‐waxy genotype, which may likely due to early recognition of the suitable host in the presence of lupeol, ultimately aiding in speedy germination and growth of the pathogen setting pace for pathogenesis.

Integrated physiological, biochemical, and transcriptomic analyses of Bruguiera gymnorhiza leaves under long-term copper stress: Stomatal size, wax crystals and composition

Copper (Cu) is a necessary mineral nutrient for plant growth and development and is involved in several morphological, physiological, and biochemical processes; however, high concentrations of Cu can negatively impact these processes. The role of stomata in responding to various biotic and abiotic stimuli has not been studied in Bruguiera gymnorhiza, particularly in terms of their coordinated interactions at the molecular, physiological, and biochemical levels. Moreover, numerous plants employ strategies such as the presence of thick waxy cuticles on their leaf epidermis and the closing of stomata to reduce water loss. Thus, this study investigates the accumulation of Cu in B. gymnorhiza and its effect on leaf morphology and the molecular response under different Cu treatments (0, 200, and 400 mg L⁻¹, Cu0, Cu200, and Cu400, respectively) during a two years stress period. The results show that Cu stress affected accumulation and transport, increased the activities of peroxidase and ascorbate peroxidase, concentrations of soluble sugar, proline, and H2O2, and decreased the activity of catalase and content of malondialdehyde. Also, Cu-induced stress decreased the uptake of phosphorus and nitrogen and inhibited plant photosynthesis, which consequently led to reduced plant growth. Scanning electron microscopy combined with gas chromatography-mass spectrometry showed that B. gymnorhiza leaves had higher wax crystals and compositions under increased Cu stress, which forced the leaf’s stomata to be closed. Also, the contents of alkanes, alcohols, primary alcohol levels (C26:0, C28:0, C30:0, and C32:0), n-Alkanes (C29 and C30), and other wax loads were significantly higher, while fatty acid (C12, C16, and C18) was lower in Cu200 and Cu400 compared to Cu0. Furthermore, the transcriptomic analyses revealed 1240 (771 up- and 469 downregulated), 1000 (723 up- and 277 down-regulated), and 1476 (808 up- and 668 downregulated) differentially expressed genes in Cu0 vs Cu200, Cu0 vs Cu400, and Cu200 vs Cu400, respectively. RNA-seq analyses showed that Cu mainly affected eight pathways, including photosynthesis, cutin, suberin, and wax biosynthesis. This study provides a reference for understanding mangrove response to heavy metal stress and developing novel management practices.

Synthesis of chain‐end functionalized highly branched polyethylene waxes using sterically open α‐diimine Ni(II) catalysts

AbstractOur previous research showed that bis(benzocyclopentyl) α‐diimine Pd(II) complexes can facilitate chain transfer and polar monomer insertion in ethylene (co)polymerization. In this study, we synthesized two bis(benzocyclopentyl) α‐diimine Ni(II) complexes with different backbones. The Ni(II) complexes exhibited high activities (0.63–7.23 × 106 g·mol−1 h−1) and produced low molecular weight (2.7–7.8 kg mol−1) polyethylene waxes with high branching densities (43–86/1000 C) in ethylene polymerization. The use of a catalyst with a butyl backbone resulted in polyethylene waxes with significantly higher molecular weights. The axial substituent restriction strategy employed in the nickel catalyst allows for a sterically open structure, reducing the molecular weight of the resulting polyethylene by over two orders of magnitude, compared to ethyl catalysts without axial restrictions. This enables the production of polyethylene wax grade products with improved properties. The branched polyethylene wax chain ends were found to be aryl‐functionalized according to NMR characterization analysis, while the double bonds were absent. Also, the choice of solvent affects the branching, molecular weight, and chain end composition of the polyethylene wax.

ZmCER1, a putative ECERIFERUM 1 protein in maize, functions in cuticular wax biosynthesis and bulliform cell development

The cuticular wax, acting as the ultimate defense barrier, is essential for the normal morphogenesis of plant organs. Despite this importance, the connection between wax composition and leaf development has not been thoroughly explored. In this study, we characterized a new maize mutant, ragged leaf4 (rgd4), which exhibits crinkled and ragged leaves starting from the sixth leaf stage. The phenotype of rgd4 is conferred by ZmCER1, which encoding an aldehyde decarbonylase involved in wax biosynthesis. ZmCER1 function deficient mutant displayed reduced cuticular wax density and disordered bulliform cells (BCs), while ZmCER1 overexpressing plants exhibited the opposite effects, indicating that ZmCER1 regulates cuticular wax biosynthesis and BCs development. Additionally, as the density of cuticular wax increased, the water loss rate of detached leaf decreases, suggesting that ZmCER1 is positively correlated with plant drought tolerance.

The cuticular wax composition and crystal coverage of leaves and petals differ in a consistent manner between plant species.

Both leaves and petals are covered in a cuticle, which itself contains and is covered by cuticular waxes. The waxes perform various roles in plants' lives, and the cuticular composition of leaves has received much attention. To date, the cuticular composition of petals has been largely ignored. Being the outermost boundary between the plant and the environment, the cuticle is the first point of contact between a flower and a pollinator, yet we know little about how plant-pollinator interactions shape its chemical composition. Here, we investigate the general structure and composition of floral cuticular waxes by analysing the cuticular composition of leaves and petals of 49 plant species, representing 19 orders and 27 families. We show that the flowers of plants from across the phylogenetic range are nearly devoid of wax crystals and that the total wax load of leaves in 90% of the species is higher than that of petals. The proportion of alkanes is higher, and the chain lengths of the aliphatic compounds are shorter in petals than in leaves. We argue these differences are a result of adaptation to the different roles leaves and petals play in plant biology.