Submitted to: Association for the Advancement of Industrial Crops Conference
Publication Type: Abstract Only
Publication Acceptance Date: 8/12/2002
Publication Date: N/A
Technical Abstract: This study is being conducted to determine whether the insertion of genes that synthesize precursors in the rubber biosynthesis pathway can increase rubber production in guayule (Parthenium argentatum), thereby increasing overall rubber yield. Three lines, AZ101, N6-5 and G7-11, had either farnesyl diphosphate (FPP) synthase or geranylgeranyl diphosphate (GGPP) synthase inserted using Agrobacterium mediated transformation. Controls were the same lines transformed with the plasmid that lacked the genes for FPP synthase or GGPP synthase. The transformants were isolated on a kanamycin selection media. Plants were proliferated in tissue culture before being transferred to the soil, and then transplanted into the field at The University of Arizona, Maricopa Agricultural Center in May and October 2001. Beginning in November 2001, height and width measurements were taken monthly. Stem samples for rubber and resin analysis were harvested 3 May 2002. Most plants had very little growth between November 2001 and March 2002, but significant increases in both height and width occurred between March and May 2002. There were no significant differences between heights of the transformants and their controls, with the exception of the AZ101 transformants A1-4 e and A4-4 a, which were significantly larger. There were no consistent patterns in width between transformants and their controls. Rubber and resin contents for each transformant are currently being analyzed. It appears from initial growth data that most transformants are not responding to transformation with increased growth, with the possible exception of the AZ101 transformants mentioned previously.