Submitted to: Association for the Advancement of Industrial Crops Conference
Publication Type: Proceedings
Publication Acceptance Date: August 30, 2001
Publication Date: N/A
Technical Abstract: Reports indicate that the organic-solvent extractable rubber content in guayule (Parthenium argentatum, Gray) is higher in the winter than in the summer months. This information can be used to schedule harvest. We refer to rubber as total or solid rubber used in making tires. Interest has now focused on the hypoallergenic latex form of rubber, which is presently obtained with a water-based extraction process. Solvent-based and water-based rubber extracts may not be the same. The objective of this study was to determine the seasonal latex content to optimize plant harvest. Latex contents of four lines were determined every two months for a period of approximately three years. Field-grown, whole plants were harvested and chipped within three hours of sampling. Latex was removed from the plant using a water-based extraction procedure. The whole plant was ground in a hammer mill chipper where the chipped material was immediately immersed into a pH-adjusted solution with an antioxidant. This chipped material was further ground in a blender. The latex in the homogenate was separated by coagulation and centrifugation. The latex content of the various lines was similar. However, the biomass of the various lines was different. Because the latex yield is based on latex concentration and biomass, the faster growing, larger lines would be preferred to obtain the largest yield. Variations were present for latex content with season, the highest occurring between March through April; but for practical purposes, harvest could be done throughout the year without drastically reducing latex yield.