Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 2/15/2007
Publication Date: 4/22/2007
Citation: Martins, M.A., Mcmahan, C.M., Wood, D.F., Moreno, R.M., Mattoso, L.H., Goncalves, P.S. 2007. Particle size investigation on natural rubber from different clones of Brazilian IAC series. The 6th International Symposium on Natural Polymers and Composites, XI International Macromolecular Colloquium, April 22-25, 2007, Gramado, Brazil. Interpretive Summary: The USDA’s Domestic Natural Rubber project has studied the biochemistry of rubber biosynthesis in divergent species, with a focus on natural rubber from Parthenium argentatum, guayule, a woody desert shrub suitable for cultivation in some parts of the United States. The reported studies of the chemistry of rubber biosynthesis, reported here and elsewhere, have typically explored interspecies comparisons in order to elucidate biosynthetic mechanisms. Our collaboration provides the opportunity to study within-a-species clonal variations from both a technological and biochemical perspective. A greater understanding of rubber biosynthesis and its regulation will allow production of greater yields of higher molecular weight rubber molecules, whether applied to breeding programs, metabolic engineering, or possibly agronomic practices. Moreover, lessons learned from the study of H. braziliensis will greatly contribute to development of P. argentatum and other rubber-producing species. The collaboration with Embrapa Instrumentação Agropecuária Sao Carlos, Brasil, is part of the ARS/Embrapa LABEX program.
Technical Abstract: Hevea brasiliensis species are being investigated in order to increase the production of natural rubber and to develop new clones more appropriate to specific soil and climate. Particle size of natural rubber from Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. - Arg. coming from new clones from the IAC series (IAC 405, 406, 410, 413, 420, 300, 301, 302, 303, 56, and 40) and from RRIM 600 (used as a control) has been studied using laser light scattering and scanning electronic microscopy (SEM). The results have shown that the average size of rubber particles varies within and among clones. In average, the particle size of clones from Votuporanga city is larger than that of those from Mococa city. The rubber particles of IAC clones exhibited predominantly a spherical shape characteristic of Hevea and other rubber species.