Submitted to: Association for the Advancement of Industrial Crops Conference
Publication Type: Abstract only
Publication Acceptance Date: 10/10/2003
Publication Date: 10/15/2003
Citation: MAJEAU, G.H., RAY, D.T., COFFELT, T.A., FOSTER, M.A. 2003. NEW GUAYULE (PARTHENIUM ARGENTATUM GRAY) VARIETY TRIALS. ASSOCIATION FOR THE ADVANCEMENT OF INDUSTRIAL CROPS CONFERENCE. p. 14. Interpretive Summary:
Technical Abstract: Complementary data on guayule varieties along with guidelines on suitable locations for its growth and management practices are needed. Nine locations were chosen for a breeding yield trial, Marioca (AZ), Marana (AZ), Yuma (AZ) (2 sites), Pecos (TX), Tucson (AZ), Safford (AZ), Los Cruces (NM), and Saltillo (Mexico). The different locations were chosen for their differences in elevation, annual rainfall, frost-free season, and soil type. The following summary only concerns the first 5 locations; i.e., the Maricopa Agricultural Center, Marana Agricultural Center, and two at the Yuma Agricultural Center, which are all part of The University of Arizona and the Texas A&M Research Station, Pecos, TX. A total of 14 different lines (1159; AZ-1; AZ-2; AZ-3; AZ-4; AZ-5; AZ-6; AZ-101; AZ-R2; N565; N6-5; N9-3; G1-16) were planted in a completely randomized complete block design with 4 replicates in Maricopa on 27 and 28 November 2001, in Marana on 16 May 2002, at both sites in Yuma (the first 13 lines only) on 29 and 30 May 2002, and in Pecos (the first 13 lines only) on 2 May 2002. Measurements taken at each site included: stand count after planting; plant height and width (twice a year, late October-early November and late April-early May); latex, rubber and resin content; and plant biomass (yearly for 3 years starting 2 years after planting). After only 2 sets of plant measurements (height and width), four ines (AZ-1, AZ-2, AZ-3, and AZ-101), common to all locations, have a higher growth rate. Although these lines do better overall, differences in plant height among the various locations for these 4 lines are quite different. For instance, even with 6 months difference in the planting date, the plant heights from Marana are comparable with the ones from Maricopa for the fall 2002 measurement (Pr greater than 0.0001). Early in the trials, and with only one year's data, no conclusions can be made at this time. However, environmental factors such as elevation, annual rainfall, frost-free season, soil type, and also the field management (irrigation, fertilization and weed control) may be responsible for the differences among locations. These trials will help establish the lines that have the best commercial potential for growers in different locations where guayule will be grown. It can also provide useful guideline information for future guayule growers.