|FOSTER, M - Texas Agrilife Research|
|PETTY, A - Texas Agrilife Research|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/14/2010
Publication Date: 9/18/2010
Citation: Foster, M.A., Coffelt, T.A., and Petty, A.K. (2010). Guayule Production on the Southern High Plains. 22nd Annual Meeting of the Association for the Advancement of Industrial Crops, September 18 - 22, 2010, Fort Collins, CO, p. 5.
Technical Abstract: Native guayule populations are scattered throughout 300,000 km2 of rangeland in the Chihuahuan Desert and surrounding regions. The only native indigenous U.S. stands occur in the Trans Pecos region of southwestern Texas, and represent the most northern extension of the plant’s habitat. Maximum air temperatures of over 38oC are frequent and minimum temperatures of -23 degrees Celsius have been recorded. The objective of our study was to determine if guayule production could be successful farther north on the Southern High Plains near Halfway, TX. Seed used in the experiment included four released lines, AZ-1, AZ-2, AZ-3, and AZ-4; a released USDA cultivar (11591); and three unreleased breeding lines, N9-3, N6-5, and N13-1. Guayule seedlings (60 days-old) were transplanted on May 18, 2006, at the Texas AgriLife Research Station at Halfway. The experimental design was a randomized complete block with four replications. Plots were single rows (each containing 18 plants of each line) spaced 1 m apart and 6 m long. Plant height was measured November 7, 2006, June 6, 2007, October 21, 2007, and June 18, 2008. Guayule cold damage was estimated June 6, 2007, using the following index: (1) no damage, (2) slight – injury of terminals to 6 cm, (3) moderate – 2/3 of plant volume injured, (4) severe – all aerial portions killed but resprouting, and (5) complete – beyond recovery with no regrowth. Two plants from each plot were harvested by hand on April 15, 2008 and March 30, 2009, weighed, and ground in a Troy-Bilt Chipper/Shredder. Samples were collected for moisture and rubber and resin content, and stored at -20 degrees Celsius. Biomass yields were determined on oven dry weights. Following the 2006/2007 winter the cold damage index ranged from 1.2 in 11591 to 3.8 in AZ-1. The minimum air temperature recorded was -14 degrees Celsius. There was minimal cold damage during the 2007/2008 and 2008/2009 winters. Biomass of the 24 month-old shrubs harvested in 2008 varied from 9,639 kg/ha in line 11591 to 13,393 kg/ha in line AZ-4. Shrub biomass in 2009 ranged from 26, 721 kg/ha in 11591 to 32,951 kg/ha in N6-5. Rubber yield in 2008 was 222 and 639 kg/ha in lines AZ-3 and N6-5, respectively. Line AZ-3 yielded 717 kg/ha of rubber in 2009 while line AZ-4 yielded 2006 kg/ha. Lines 11591 and N6-5 had the least cold damage and hold promise for establishment and rubber production on the Southern High Plains. Guayule grown here will not produce the biomass of those cultivated in the Southwest, but certain production criteria may make the Plains an ideal production site: annual rainfall averages 46 cm, irrigation water salinity is less than 1 E.C. and is pumped from only 90 m, and center pivots are available for establishing guayule by direct-seeding.