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Kenneth A. Feldmann - One of the best experts on this subject based on the ideXlab platform.
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CORRELATIONS BETWEEN Epicuticular Wax STRUCTURES AND CHEMICAL COMPOSITION IN ARABIDOPSIS THALIANA
International Journal of Plant Sciences, 1998Co-Authors: Aaron M. Rashotte, Kenneth A. FeldmannAbstract:The Epicuticular Waxes of vascular plants are both chemically and structurally diverse. This investigation attempts to clarify the poorly understood relationships between Epicuticular Wax chemicals and structures by correlating the diversity of chemical compositions and structures in wildtype and Epicuticular Wax mutants of Arabidopsis thaliana. An expanded classification of A. thaliana Epicuticular Wax structures was conducted preceding their quantification on 24 genotypes of A. thaliana. Correlations between all A. thaliana stem Epicuticular Wax chemical and structural categories showed that 19 of the 26 Epicuticular Wax compounds were significantly correlated to at least one of the six structural types. The chain-length distribution of an Epicuticular Wax profile was also found to be correlated to structural type: short chain-length compounds to dendritic structures and long chain-length compounds to umbrella structures. The 29-carbon-length alkane, ketone, and secondary alcohol are each correlated to ...
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Epicuticular Wax variation in ecotypes of Arabidopsis thaliana
Phytochemistry, 1997Co-Authors: Aaron M. Rashotte, Matthew A. Jenks, Thanh D. Nguyen, Kenneth A. FeldmannAbstract:Quantification of the Epicuticular Wax from the stems of 40 ecotypes of Arabidopsis thaliana showed a two-fold range in total Wax load that was not correlated to known abiotic characteristics of the ecotype's origin of collection. Chemical analysis of these ecotypes revealed similar Epicuticular Wax profiles for all ecotypes except CT-1. In CT-1 the amount of 22 and 24 carbon length primary alcohols was increased by 16- and 8-fold, respectively, over that observed in the Epicuticular Wax averaged over all ecotypes.
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Mutants in Arabidopsis thaliana Altered in Epicuticular Wax and Leaf Morphology
Plant physiology, 1996Co-Authors: Matthew A. Jenks, Aaron M. Rashotte, Hillary A. Tuttle, Kenneth A. FeldmannAbstract:We report eight new mutants in Arabidopsis thaliana possessing altered leaf morphology and Epicuticular Wax. These were isolated from a T-DNA-mutagenized population using a visual screen for altered leaf reflectance, i.e. increased glaucousness or glossiness. The mutants were placed into three distinct classes based on alterations in overall plant morphology: knobhead (knb), bicentifolia (bcf), and Wax. The four knb mutants formed callus-like growths in the axillary region of the rosette leaves and apical meristem, the two bcf mutants produced hundreds of narrow leaves, and the two Wax mutants had leaves and stems that were more glossy than wild type and organs that fused during early development. Leaves of knb and bcf were more glaucous and abnormally shaped than wild type. Epicuticular Wax crystals over knb and bcf leaf surfaces (where none were present on wild type) likely contributed to their more glaucous appearance. In contrast, the glossy appearance of the Wax mutants was associated with a reduced Epicuticular Wax load on both leaves and stems. One representative from each phenotypic class was selected for detailed analyses of Epicuticular Wax chemistry. All three lines, knb1, bcf1, and Wax1, had dramatic alterations in the total amounts and relative proportions of their leaf Epicuticular Wax constituents.
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Epicuticular Wax and eceriferum mutants.
Cold Spring Harbor Monograph Archive, 1994Co-Authors: Bertrand Lemieux, Maarten Koornneef, Kenneth A. FeldmannAbstract:Like most plants, the aboveground surface of Arabidopsis thaliana is covered by a layer of lipids such as fatty acids, fatty aldehydes, primary alcohols, alkanes, secondary alcohols, ketones, and esters. Figure 1 illustrates the chemical structures of some of the principal Epicuticular Wax components found on the surface of Arabidopsis. The majority of these Wax components can be separated in a single chromatographic separation by capillary gas chromatography with a low polarity solid phase (Yang et al. 1992). The use of mass spectrometry coupled to a gas chromatograph has allowed the identification of the individual compounds that make up the Epicuticular Wax layer of plants (Walton 1990). As shown in Figure 2, Arabidopsis eceriferum ( cer ) mutants are characterized by a bright green color when compared to wild-type plants because the reduced amount of Wax deposition on the stem alters the reflection of light such that mutants can be isolated by a simple visual inspection. Epicuticular Wax components are derived from very long chain fatty acids. The existence of a fatty acid elongation activity within the endoplasmic reticulum has been demonstrated by the partial purification of a 500-kD enzyme complex that elongates stearyl-CoA (18:0) to eicosanoyl-CoA (20:0) (Bessoule et al. 1989). Partial purifications of fatty acid reductase activities have shown that a fatty acid reductase and a fatty aldehyde reductase activity can be separated by protein fractionation (Kolattukudy 1971). Experiments with particulate cell wall fractions of pea have demonstrated that a fatty aldehyde decarbonylation activity is presumably responsible for the biosynthesis...
Heather E. Pence - One of the best experts on this subject based on the ideXlab platform.
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Interaction of organic solvents with the Epicuticular Wax layer of wheat leaves.
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Kyung Myung, Alexander P. Parobek, Jeffrie A. Godbey, Andrew J. Bowling, Heather E. PenceAbstract:After foliar application, compounds that are not absorbed into leaves can be removed from the leaf surface by dipping or rinsing in dilutions of organic solvents in water. However, interactions between solvent mixtures and the Epicuticular Wax layer have received little attention, and information on potential physical and chemical intactness of the plant surface following application of solvents is limited. In this study, wheat leaves were dipped in organic solvents at different dilutions with water, and the major component of the leaf Epicuticular Wax layer, 1-octacosanol, was analyzed to assess damage to the Wax layer. Dipping leaves in dilutions of organic solvent higher than 60% by volume resulted in only negligible or low levels of 1-octacosanol extraction, while no 1-octacosanol was detected in any mixtures containing less than 40% organic solvent. Furthermore, analysis of leaf surfaces by scanning electron microscopy showed structural intactness of the Epicuticular Wax layer when organic solvent mi...
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Interaction of organic solvents with the Epicuticular Wax layer of wheat leaves.
Journal of agricultural and food chemistry, 2013Co-Authors: Kyung Myung, Alexander P. Parobek, Jeffrie A. Godbey, Andrew J. Bowling, Heather E. PenceAbstract:After foliar application, compounds that are not absorbed into leaves can be removed from the leaf surface by dipping or rinsing in dilutions of organic solvents in water. However, interactions between solvent mixtures and the Epicuticular Wax layer have received little attention, and information on potential physical and chemical intactness of the plant surface following application of solvents is limited. In this study, wheat leaves were dipped in organic solvents at different dilutions with water, and the major component of the leaf Epicuticular Wax layer, 1-octacosanol, was analyzed to assess damage to the Wax layer. Dipping leaves in dilutions of organic solvent higher than 60% by volume resulted in only negligible or low levels of 1-octacosanol extraction, while no 1-octacosanol was detected in any mixtures containing less than 40% organic solvent. Furthermore, analysis of leaf surfaces by scanning electron microscopy showed structural intactness of the Epicuticular Wax layer when organic solvent mixtures were used. Therefore, our results demonstrate that the Epicuticular Wax layer of wheat leaves is not altered physically or chemically by organic solvent solutions up to 40% by volume. These findings validate the use of solvent washing procedures to assess unabsorbed compounds on wheat leaf surfaces.
Matthew A. Jenks - One of the best experts on this subject based on the ideXlab platform.
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Mutagenesis, Selection, and Allelic Analysis of Epicuticular Wax Mutants in Sorghum
Crop Science, 2009Co-Authors: Paul J. Peters, Matthew A. Jenks, Patrick J. Rich, John D. Axtell, Gebisa EjetaAbstract:Epicuticular Wax forms an outer coating on the aerial surfaces of many crop plants and is implicated in tolerance to several environmental stresses including drought. Advances in knowledge of biosynthesis and secretion of these leaf surface Waxes could lead to improvements in crop-stress tolerance. To study the genetics of Epicuticular Wax deposition, we screened for bloomless (bm) and sparse-bloom (h) mutants with reduced glaucousness of abaxial sheath surfaces within chemically mutagenized populations of Sorghum bicolor (L.) Moench. We screened over 3974 segregating M 2 head rows with over 160,000 plants and identified 38 putative recessive Epicuticular Wax mutant alleles. We grouped 31 of these into allelic groups associated with one existing and 18 new Epicuticular Wax loci. The overall Epicuticular Wax mutation frequency was 0.88%. In addition, analysis of the mutant segregation frequencies within the M 2 rows allowed us to calculate the existence of five target meristem cells in a dormant (M 0 ) seed embryo. The high Epicuticular Wax mutation rate and identification of 19 Epicuticular Wax loci indicate the presence of a complex genetic system of Epicuticular Wax production in sorghum as has been shown in other species. The new bloomless and sparse-bloom mutants identified here have a wide range of phenotypes and constitute a valuable resource for studies of the genetics and biosynthesis of Epicuticular Waxes and their effects on tolerance to environmental stresses such as drought.
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Epicuticular Wax variation in ecotypes of Arabidopsis thaliana
Phytochemistry, 1997Co-Authors: Aaron M. Rashotte, Matthew A. Jenks, Thanh D. Nguyen, Kenneth A. FeldmannAbstract:Quantification of the Epicuticular Wax from the stems of 40 ecotypes of Arabidopsis thaliana showed a two-fold range in total Wax load that was not correlated to known abiotic characteristics of the ecotype's origin of collection. Chemical analysis of these ecotypes revealed similar Epicuticular Wax profiles for all ecotypes except CT-1. In CT-1 the amount of 22 and 24 carbon length primary alcohols was increased by 16- and 8-fold, respectively, over that observed in the Epicuticular Wax averaged over all ecotypes.
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Mutants in Arabidopsis thaliana Altered in Epicuticular Wax and Leaf Morphology
Plant physiology, 1996Co-Authors: Matthew A. Jenks, Aaron M. Rashotte, Hillary A. Tuttle, Kenneth A. FeldmannAbstract:We report eight new mutants in Arabidopsis thaliana possessing altered leaf morphology and Epicuticular Wax. These were isolated from a T-DNA-mutagenized population using a visual screen for altered leaf reflectance, i.e. increased glaucousness or glossiness. The mutants were placed into three distinct classes based on alterations in overall plant morphology: knobhead (knb), bicentifolia (bcf), and Wax. The four knb mutants formed callus-like growths in the axillary region of the rosette leaves and apical meristem, the two bcf mutants produced hundreds of narrow leaves, and the two Wax mutants had leaves and stems that were more glossy than wild type and organs that fused during early development. Leaves of knb and bcf were more glaucous and abnormally shaped than wild type. Epicuticular Wax crystals over knb and bcf leaf surfaces (where none were present on wild type) likely contributed to their more glaucous appearance. In contrast, the glossy appearance of the Wax mutants was associated with a reduced Epicuticular Wax load on both leaves and stems. One representative from each phenotypic class was selected for detailed analyses of Epicuticular Wax chemistry. All three lines, knb1, bcf1, and Wax1, had dramatic alterations in the total amounts and relative proportions of their leaf Epicuticular Wax constituents.
Kyung Myung - One of the best experts on this subject based on the ideXlab platform.
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Interaction of organic solvents with the Epicuticular Wax layer of wheat leaves.
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Kyung Myung, Alexander P. Parobek, Jeffrie A. Godbey, Andrew J. Bowling, Heather E. PenceAbstract:After foliar application, compounds that are not absorbed into leaves can be removed from the leaf surface by dipping or rinsing in dilutions of organic solvents in water. However, interactions between solvent mixtures and the Epicuticular Wax layer have received little attention, and information on potential physical and chemical intactness of the plant surface following application of solvents is limited. In this study, wheat leaves were dipped in organic solvents at different dilutions with water, and the major component of the leaf Epicuticular Wax layer, 1-octacosanol, was analyzed to assess damage to the Wax layer. Dipping leaves in dilutions of organic solvent higher than 60% by volume resulted in only negligible or low levels of 1-octacosanol extraction, while no 1-octacosanol was detected in any mixtures containing less than 40% organic solvent. Furthermore, analysis of leaf surfaces by scanning electron microscopy showed structural intactness of the Epicuticular Wax layer when organic solvent mi...
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Interaction of organic solvents with the Epicuticular Wax layer of wheat leaves.
Journal of agricultural and food chemistry, 2013Co-Authors: Kyung Myung, Alexander P. Parobek, Jeffrie A. Godbey, Andrew J. Bowling, Heather E. PenceAbstract:After foliar application, compounds that are not absorbed into leaves can be removed from the leaf surface by dipping or rinsing in dilutions of organic solvents in water. However, interactions between solvent mixtures and the Epicuticular Wax layer have received little attention, and information on potential physical and chemical intactness of the plant surface following application of solvents is limited. In this study, wheat leaves were dipped in organic solvents at different dilutions with water, and the major component of the leaf Epicuticular Wax layer, 1-octacosanol, was analyzed to assess damage to the Wax layer. Dipping leaves in dilutions of organic solvent higher than 60% by volume resulted in only negligible or low levels of 1-octacosanol extraction, while no 1-octacosanol was detected in any mixtures containing less than 40% organic solvent. Furthermore, analysis of leaf surfaces by scanning electron microscopy showed structural intactness of the Epicuticular Wax layer when organic solvent mixtures were used. Therefore, our results demonstrate that the Epicuticular Wax layer of wheat leaves is not altered physically or chemically by organic solvent solutions up to 40% by volume. These findings validate the use of solvent washing procedures to assess unabsorbed compounds on wheat leaf surfaces.
Aaron M. Rashotte - One of the best experts on this subject based on the ideXlab platform.
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CORRELATIONS BETWEEN Epicuticular Wax STRUCTURES AND CHEMICAL COMPOSITION IN ARABIDOPSIS THALIANA
International Journal of Plant Sciences, 1998Co-Authors: Aaron M. Rashotte, Kenneth A. FeldmannAbstract:The Epicuticular Waxes of vascular plants are both chemically and structurally diverse. This investigation attempts to clarify the poorly understood relationships between Epicuticular Wax chemicals and structures by correlating the diversity of chemical compositions and structures in wildtype and Epicuticular Wax mutants of Arabidopsis thaliana. An expanded classification of A. thaliana Epicuticular Wax structures was conducted preceding their quantification on 24 genotypes of A. thaliana. Correlations between all A. thaliana stem Epicuticular Wax chemical and structural categories showed that 19 of the 26 Epicuticular Wax compounds were significantly correlated to at least one of the six structural types. The chain-length distribution of an Epicuticular Wax profile was also found to be correlated to structural type: short chain-length compounds to dendritic structures and long chain-length compounds to umbrella structures. The 29-carbon-length alkane, ketone, and secondary alcohol are each correlated to ...
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Epicuticular Wax variation in ecotypes of Arabidopsis thaliana
Phytochemistry, 1997Co-Authors: Aaron M. Rashotte, Matthew A. Jenks, Thanh D. Nguyen, Kenneth A. FeldmannAbstract:Quantification of the Epicuticular Wax from the stems of 40 ecotypes of Arabidopsis thaliana showed a two-fold range in total Wax load that was not correlated to known abiotic characteristics of the ecotype's origin of collection. Chemical analysis of these ecotypes revealed similar Epicuticular Wax profiles for all ecotypes except CT-1. In CT-1 the amount of 22 and 24 carbon length primary alcohols was increased by 16- and 8-fold, respectively, over that observed in the Epicuticular Wax averaged over all ecotypes.
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Mutants in Arabidopsis thaliana Altered in Epicuticular Wax and Leaf Morphology
Plant physiology, 1996Co-Authors: Matthew A. Jenks, Aaron M. Rashotte, Hillary A. Tuttle, Kenneth A. FeldmannAbstract:We report eight new mutants in Arabidopsis thaliana possessing altered leaf morphology and Epicuticular Wax. These were isolated from a T-DNA-mutagenized population using a visual screen for altered leaf reflectance, i.e. increased glaucousness or glossiness. The mutants were placed into three distinct classes based on alterations in overall plant morphology: knobhead (knb), bicentifolia (bcf), and Wax. The four knb mutants formed callus-like growths in the axillary region of the rosette leaves and apical meristem, the two bcf mutants produced hundreds of narrow leaves, and the two Wax mutants had leaves and stems that were more glossy than wild type and organs that fused during early development. Leaves of knb and bcf were more glaucous and abnormally shaped than wild type. Epicuticular Wax crystals over knb and bcf leaf surfaces (where none were present on wild type) likely contributed to their more glaucous appearance. In contrast, the glossy appearance of the Wax mutants was associated with a reduced Epicuticular Wax load on both leaves and stems. One representative from each phenotypic class was selected for detailed analyses of Epicuticular Wax chemistry. All three lines, knb1, bcf1, and Wax1, had dramatic alterations in the total amounts and relative proportions of their leaf Epicuticular Wax constituents.