Author
VEATCH, M - U OF ARIZONA | |
RAY, D - U OF ARIZONA | |
Cornish, Katrina |
Submitted to: Association for the Advancement of Industrial Crops Conference
Publication Type: Abstract Only Publication Acceptance Date: 10/1/2003 Publication Date: 10/12/2003 Citation: Veatch, M.E., Ray, D.T., Cornish, K. 2003. Growth, rubber and resin evaluation of two year old transgenic guayule. Association for the Advancement of Industrial Crops Conference. p.10. Interpretive Summary: Guayule is under commercial development as a source of hypoallergenic latex safe for use by patients suffering from Type I latex allergy. Improvement through plant breeding has led to release of advance guayule lines. However, we are also attempting further improvements by transforming guayule with three different genes in the rubber biosynthesis pathway. Initial results indicate healthy plants with normal growth rates. Resin levels increased throughout the year up to Jan 2003, but decreased by the time of harvest in March. Rubber, on the other hand was high in May 2002, but decreased throughout the summer, before steadily increasing during the winter months. Guayulin production was low overall, especially Guayulin A production, compared to conventional lines. Guayulin A production was particularly low in the AZ 101 transformants compared to their empty vector controls. The low levels of Guayulin A, which is a potential contact allergen, may be a beneficial effect of transformation and is worth further investigation. Technical Abstract: Guayule (Parthenium argentatum, Gray) is a native source of high quality latex and rubber. Improvement through conventional selection techniques has been made and further improvement is being attempted by transforming guayule with three different genes in the rubber biosynthesis pathway. The objective of this study was to evaluate the effect of these transgenes on growth and rubber and resin production in field grown guayule. Transformation had no significant effect on growth in G7-11 and N6-5 in either plot. AZ 101 transformants were significantly larger than the empty vector AZ 101 control, but were not significantly different from the non-transformed controls. Percent resin increased throughout the year up to January 2003, but decreased by the time of harvest in March. Rubber, on the other hand was high in May 2002, but decreased throughout the summer, before steadily increasing during the winter months. Guayulin production was low overall, especially Guayulin A production, compared to conventional lines. Guayulin A production was particularly low in the AZ 101 transformants compared to their empty vector controls. Insertion of genes for precursors in the rubber biosynthetic pathway did not appear to have any affect on overall growth. However, due to the significantly lower growth in the empty vector control of AZ 101, the gene may have inserted into the genome in an area important for growth. Although transformation did not affect growth it did appear to have an affect on Guayulin A production. The low levels of Guayulin A, which is a contact allergen, may be a beneficial effect of transformation and is worth further investigation. |