A Rapid Colorimetric Method for Epicuticular Wax Contest of Sorghum Leaves¹

Abstract

Epicuticular wax deposition on sorghum [(Sorghum bicolor) L. Moenchl leaf blades imparts drought resist. ante. Screening of a large number of sorghum genotypes for increased leaf epicuticular wax content, utilizing the available gravimetric method, is ! .practical. A more rapid colorimetric method was developed and evaluated against the current gra metric method. The colorimetric method is based on the color change produced due to the reaction of wax with acidic K0Cr,.O, reagent. Wax content determined by the colorimetric method was highly correlated (r = 0 .984) with that determined by the grain. metric method. Leaf epicuticular wax content in 11 fieldgrown grain sorghum cultivars did not vat) between growth stage #4 (tip of flag leaf showing) and 37 (soft dough), at which stages comparable wax readings were obtained among the four top leaf blades. A CK 60 'bloom less' (bmbm) genotype had only half of the epicuticular content of the CK 60 'normal' (BmBm) genotype. Ten cultivars, all of the BmBm genotype, significantly differed in epiculticular wax content, ranging from 1 .14 to 1 .99 (SE = 0.00(i) mg/dm of leaf .

Relationship between Water use Efficiency and Cuticular Wax Deposition in Warm Season Forage Crops Grown under Water Deficit Conditions

“…Wax content was determined by a modification of the colorimetric method described by BRAGDON (2) and EBERCON et al (8 (20).…”

Variability in Epicuticular Wax in 35 Woody Plants in Linares, Northeast Mexico

“…Waxes are composed of long-chain paraffins, alcohols, ketones, esters and free fatty acids in proportions determined by both genetic capability and environmental factors [2][3][4]. Epicuticular wax enhances the reflectance of visible and near infrared radiation from leaf surface thereby reducing net radiation and cuticular transpiration and seems to contribute drought resistance of plants [5][6][7]. These waxes also impart resistance to plants to absorption and penetration of foliarapplied herbicides [4,8,9].…”

Chemical Control and Morphoanatomical Analysis of Leaves of Different Populations of Sourgrass

“…Wax content quantification was based on the change of color caused by reaction of wax with potassium dichromate acid, as described by Ebercon et al (1977). The second fully expanded leaf 4 from the apex of the culm was collected, totaling six leaves (of six plants), corresponding to 48 cm² of leaves per population.…”