First Year Field Evaluation of
|Michael D. Rethwisch, Michael Kruse, Javier Torres and Miguel Torres|
Nine alfalfa varieties,most not previously tested under field conditions in Arizona, were planted October 29, 1997 using the same setting on a Great Plains Solid Stand 13 End Wheel drill. Varieties differed in lbs. of seed/acre planted, ranging from 28.0 for CUF 101 to 21.3 for Alto. Five cuttings were obtained through August 1998. The variety Alto yielded the most hay in the first and fourth cuttings and had the highest total yield from the first five harvests. Varieties with fall dormancy class ratings of 8 usually had higher yields than varieties of dormancy 9 during the spring and early summer growing season, which was below normal in temperature, resulting in class 8 dormancies having the highest total yields thus far.
New alfalfa varieties continue to increase in
availablity, especially those in fall dormancy class 9,
with newly certified varieties available annually. This
experiment was begun to collect yield and other varietal
information under field conditions on many varieties that
had not been previously tested in Arizona as part of the
University of Arizona alfalfa variety testing program.
Methods and Materials
Nine alfalfa varieties (Alto, Baralfa 85, Baralfa 92, Beacon, DK191, CUF 101, SW 9301, WL 525 HQ and WL 612) were planted October 29, 1997 with a Great Plains Solid Stand 13 End Wheel Drill into a field located approximatley 5 miles south of Poston, AZ, on the Colorado River Indian Tribes Reservation. Field soil types consist of approximately 98% Cibola-Agualt clay loam and 2% Holtville-Kofa complex.
All varieties were planted using the same planter setting, which was expected to apply 27 lbs./acre of CUF 101. Plots were 0.741 acres in size (26 feet long x 1,241 ft. long), and experimental design was a randomized block with four replications. Fields were treated with the herbicide Poast Plus for reed canarygrass control on Dec. 11.
Five harvests have been obtained thus far in 1998, with plots cut on March 13, May 2, June 3-4, July 8-9 and August 11. After baling, bales for each plot were counted, and several bales (3-5) per plot were weighed to obtain average weight for each plot. Yields were then calculated on a per acre basis.
Quality samples were taken from the August harvest by
coring several bales/plot with a Utah sampler, combining
samples to make a composite sample for each variety.
Samples were submitted for near infrared analysis.
Results have not yet been received.
Differences existed in amount of seed planted per acre, with CUF 101 planting more lbs. of seed/acre than other varieties and Alto planting the least Table 1. This is thought to be due to seed size with the smaller seeded varieties planting more lbs/acre than the larger seeded varieties.
Three varieties (CUF 101, Baralfa 85, and Baralfa 92) had more vigorous growth early after germination than other varieties being evaluated. First cutting yields Table 1 did not correlate with the early vigorous growth, however, although some weed suppression was visually noted in these varieties but not documented.
Alto was the highest yielding variety thus far in the trial, and the dormancy class 8 varieties (Alto, WL525HQ, and Baralfa 85) were the highest yielding varieties. This may be due in part to the spring and early summer temperatures being below normal, favoring the class 8 fall dormancy varieties during this time period when the majority of the data were collected.
Statistical differences in yield did exist for the
first harvest Table 1 but were not significant in
subsequent harvests from May through July.
This study is supported in part by Barenbrug USA, Germain's Seeds, Great Plains Research, Kamprath Seed Co., S&W Seed Co., and Union Seed.
This is a part of publication
AZ1059: "1998 Forage and
Grain Agriculture Report," College of Agriculture,
The University of Arizona, Tucson, Arizona, 85721.