Small Grain Variety Trials
Small plot replicate trials were established to test ten barley varieties, twenty one durum wheat varieties and seven varieties of bread/feed wheat. Yields were exceptionally high in 1998 which were attributed to overall growing conditions for the plants. Gustoe was the highest yielding barley variety with a yield of 8412 pounds per acre, YU894-162 (Western Plant Breeders) was the highest yielding durum wheat with a yield of 7986 pounds per acre and RSI 5 (Resources Seeds Inc.) was the highest yielding feed wheat. These varieties yielded 1458, 966 and 713 pounds per acre more than the number two varieties for barley, durum wheat and wheat, respectively.
After one year with no wheat on the Agricultural Center, we have restarted the wheat variety testing program. The Karnal Bunt issue still exits in the state, but no further spore have been found at the higher elevations so the pressure has declined somewhat in the southeastern part of Arizona. The barley variety testing program continued through the years and along with the wheat studies, our objective is to provide current varietal evaluations for farmers who are able to fit small grains into their rotation. It is desirable to have a rotation instead of a cotton mono-culture in Graham county, but the economics of growing small grains over the past decade have not been very favorable.
Materials and Methods
Prior to planting the variety trials, the ground is prepared and beds are pulled and firmed, so seed placement will be somewhat consistent from top of beds to bottom of furrows. Plots were planted with a six-foot Van Brunt grain planter with fertilizer attachment, over two 36" beds. The cultural practices applied are described below in the crop history.
The plots were harvested using a Gleaner Model L combine, catching the grain from each plot in a 5 gallon bucket in the grain bin. These buckets were weighed using a hanging scale and samples were taken to determine moisture and bushel weight.
Results and Discussion
Results of the barley study are found in Table 1. Conditions were nearly ideal with the highest yielding variety yielding almost twice as much as the highest yielding variety in the previous yearís trial (1). Yields as high as 4 tons per acre are achieved in other parts of the county on a regular basis, but on the salty soils of the Agricultural Center, this is a rare event. Gustoe, a strong variety for many years, was the highest yielding variety with Nebula, the highest yielding variety from 1997 coming in 4th place, nearly 24% lower yield than Gustoe. Coincidentally, Gustoe was the top yielding variety in the study in Marana in 1997 (2). In the table, Patti had the highest bushel weight and Max had the lowest. The average bushel weight was much higher than the average barley bushel weight of 48 pounds. In plant height, UC 337 was the tallest plant and Mucho was the shortest. The 1000 kernal weights were much higher than last year (1) and the average of 41.0 grams was much higher than the national average of 33.6 grams.
Table 2. contains information on the durum wheat study. The highest yielding variety was YU 894-162, a variety not tested in the area before, from Western Plant Breeders. In addition to its yield being 13% higher than the second variety, the bushel weight, 1000 kernal weight, percent protein and hard vitreous amber count (HVAC) were above the average for the trial and exceeded the values of WestBred 881 which has been the standard for quality. The average yield for this study exceeded the yield of the previous durum wheat variety trial on the Agricultural Center (3) by 1660 pounds. The reason for the high yields has not been fully explored, but probably relates to favorable climatic conditions and the addition of 400 pounds per acre of elemental sulphur. DuraKing, the high yielding variety in the previous trial came in next to last in this study.
Bread and feed wheat variety studies are reported in Table 3. The highest yielding variety, RSI 5 (Resources Seeds International, Woodland, CA) was placed in the trial because it was the leading variety in 5 counties in northern California in 1997 (4). RSI 5 yielded more than 700 pounds per acre more than Cuyama, but it must be noted that its quality is not the same. Its bushel weight, percent protein and HVAC were the lowest of those varieties tested. If Cuyama sold at 5¢ per pound then RSI 5 would have to sell for at least 4.5¢ per pound to produce as much income per acre. The yield genetics are present in RSI 5, the market place will have to determine if it is the best choice to plant in this area. As reported with the durum wheat, yields were significantly higher in 1997 than in our previous study.
This is a part of publication AZ1059:
"1998 Forage and Grain Agriculture Report," College of Agriculture, The
University of Arizona, Tucson, Arizona, 85721.