Forage & Grain Report 1988
ABOUT THE COLLECTION
The Forage and Grain Report is one of several commodity-based agricultural research reports published by the University of Arizona.
This report, along with the Cotton Report, was established by Hank Brubaker, Extension Agronomist, after seeing a similar report published by Texas A&M University in the mid-1970’s.
The purpose of the report is to provide an annual research update to farmers, researchers, and those in the agricultural industry. The research is conducted by University of Arizona and USDA-ARS scientists.
Both historical and current Forage and Grain Reports have been made available in the UA Campus Repository as part of a collaboration between the College of Agriculture and Life Sciences and the University Libraries.
Contents for Forage & Grain Report 1988
- Breeding Strategies for Alfalfa Grown Under Saline Conditions
- Development of Grazing-tolerant Alfalfa for the Southwest
- The Role of Cercospora Summer Black Stem and Leaf Spot in the Alfalfa Decline Problem in La Paz County
- The Relationship Between Ten Alfalfa Varieties and the Presence of Weeds After Two Years
- Timing Nematicide Application for Control of Stem Nematodes Infecting Arizona Alfalfa
- Effects of Salinity on the Water Potential of Alfalfa Seedlings
- The Effects of Alfalfa Seed Scarification in Saline Environments
- Salinity X Temperature Interactions on Germination Salt Tolerant Alfalfa
- Alfalfa Varieties from the 1920s to the 1980s: Comparison of Forage Yield During the Seedling Year
- Yield and Quality of Alfalfa Varieties at the Mohave Valley, 1986-1987
- Alfalfa Variety Demonstration at the Safford Agricultural Center, 1984-87
- Alfalfa Variety Trial in Greenlee County, 1987
- Barley Response to Water and Nitrogen, 1988
- Cultural Practices of One-Irrigation Barley at Marana, 1988
- Seeding Rate and Row Spacing for WestBred 881 and Aldura Durum at Marana, 1988
- Durum Seeding Methods, 1988
- Feed Wheat Variety and Rate of Planting Demonstration in Graham County, 1988
- Evaluation of the Accuracy of a Wheat Stem Nitrate Test in Predicting Nitrogen Requirements of Irrigated Durum Wheat
- Comparison of Residual Nitrate and Fertilizer Nitrogen Efficiency in Basin Irrigated Wheat
- Effects of P Applications on Wheat Tissue Phosphate Levels and Grain Production in Graham County
- Evaluation of Plant Growth Regulators on Wheat in Arizona, 1987
- Effect of Russian Wheat Aphid on Durum Wheat Yield
- Wheat Irrigation Scheduling at the Safford Agricultural Center, 1988
- Small Grain Variety Comparisons at the Maricopa Agricultural Center, 1988
- Wheat and Durum Variety Trial at the Bruce Church Ranch, Poston, 1988
- Barley Variety Trial at the Safford Agricultural Center, 1988
- Barley Variety Trial in Cochise County, 1988
- Oat Varieties Grown for Grain and Forage Production at the Safford Agricultural Center, 1988
- Oat Variety Trial in Cochise County, 1988
- Bermuda Grass insect Control
- Corn Variety Trial in Bonita, Cochise County, 1987
- Corn Variety Trial in Greenlee County, 1987
- Double Crop Grain Sorghum Variety Trial in Graham County, 1987
- Stomate Density and Physiological Measurements on Leaves of Alkali Sacaton
- Revegetation of Retired Farmland: Response of Range Grasses to Establishment Irrigations and Microcatchment Water Harvesting
- Revegetation of Retired Farmland: Response of Fourwing Saltbush to Establishment Irrigations and Weeding
- Revegetation of Retired Farmland: Evaluation of Six Range Grasses Under Three Irrigation Regimes
Revegetation of Retired Farmland: Evaluation of Six Range Grasses Under Three Irrigation RegimesBuffelgrass, kleingross, "Catalina" lovegrass, "Cochise" lovegrass, bottlebrush, and sideoats grama grass were seeded on retired farmland in the Avra Valley west of Tucson in 1986 and again in 1987. Each grass species was seeded in plots that received no irrigation, or two establishment irrigations or four establishment irrigations. For both year's tests, buffelgrass had a significantly higher percent cover than the other grasses at three months after planting. In the evaluation of the 1986 test in October 1987, buffelgrass, kleingrass, Cochise lovegrass, and Catalina lovegrass had increased their presence in the irrigated plots from one year before and appeared promising for the revegetaion of retired farmland. Plots that did not receive establishment irrigations did not have significantly higher cover ratings than plots with no cover at all. The one exception to this was buffelgrass in the first evaluation of the 1986 test.
Revegetation of Retired Farmland: Response of Fourwing Saltbush to Establishment Irrigations and WeedingFourwing saltbush (Atriplex canescens) was seeded in 80 -inch wide water harvesting microcatchments on retired farmland west of Tucson. Eight months after planting the plots that had received one establishment irrigation and weeding had significantly more cover than the unirrigated and unweeded treatments. The percent cover of the uninigated /weeded and irrigated /unweeded treatments was not significantly different. Uninigated and unweeded plots had virtually no cover of saltbush. It appears that establishing saltbush in microcatchments of this size is not feasible without either an establishment irrigation or weed control.
Revegetation of Retired Farmland: Response of Range Grasses to Establishment Irrigations and Microcatchment Water HarvestingIn July 1987, an experiment was initiated to evaluate the effects of water harvesting and establishment irrigations on the establishment and persistence of buffelgrass, kleingrass, and sideoats grama grass on retired farmland A density evaluation in November 1987 revealed a significant increase in percent cover of the grasses due to establishment irrigations. No significant differences were detected among water harvesting treatments or flat- disked controls. Evaluations will continue to measure any long-term effects from these treatments.
Double Crop Grain Sorghum Variety Trial in Graham County, 19871987 was a better year for double -crop grain sorghum than the previous year. The yields increased to nearly a ton per acre. The top - yielding variety was Asgrow Topaz at 7,885.7 pounds per acre. This yield topped the standard variety, DeKalb 64 by almost 4 percent. Bird damage was also reduced this year.
Corn Variety Trial in Bonita, Cochise County, 1987The 1987 trials included 14 commercial corn hybrids, which were tested on a heavy - textured soil in northern Cochise county; they were the better yielding hybrids from the previous trial. Five new entries, not previously tested in Cochise county, were included. Garst 8345, one of the new entries, was both the top - yielder, at 12,499 pounds per acre, and the hybrid producing the highest adjusted gross income per acre. Hybrids produced by Pioneer, Cargill, DeKalb and NC+ seed companies all yielded more than 12,000 pounds per acre.
Oat Variety Trial in Cochise County, 1988Ten varieties of oats were grown in a trial to test grain yield. Five of the varieties produced more than 4,000 pounds per acre; the top - yielding variety, Ogle, from Minnesota, produced 4,578 pounds per acre. Difficulties in establishing a perfect stand with the small plot grain drill would probably mean that a farmer could expect yields higher than these when using full -sized equipment. Considering the premium for oats, oats for grain could be a viable alternative crop.
Oat Varieties Grown for Grain and Forage Production at the Safford Agricultural Center, 1988Eleven oat varieties were tested for grain and forage yields at the Safford Agricultural Center. Cayuse, the predominant variety grown in the area was the top producer of total dry matter. Four other varieties had higher grain yields than Cayuse.
Barley Variety Trial in Cochise County, 1988Eight barley varieties were tested in a replicated variety trial in northern Cochise county. These varieties varied from relatively early maturing varieties, such as Barcot4 to the longer maturing varieties, such as Gustoe. The medium -late variety, Northrup King 1558, was the top - yielding variety, with 7,185 pounds per acre. This exceeded the yield of the standard variety, Gustoe, by 15 percent, making NK 1558 a variety that should be looked at further. It will be marketed by Northrup King under the name Sunbar 458.
Barley Variety Trial at the Safford Agricultural Center, 1988Nine varieties of barley were tested at the Safford Agricultural Center in response to growers' requests for high yielding barley varieties with the potential to mature more quickly than Gustoe. Gustoe was the top- yielding variety with 5,551 pounds per acre. A University of California variety was a close second but it has the same maturity as Gustoe. The varieties that mature more quickly, Barcott and Fiesta, yielded approximately 1,500 pounds fewer than Gustoe.
Wheat Irrigation Scheduling at the Safford Agricultural Center, 1988Wheat irrigations were scheduled using two computer models and an infrared thermometer using two critical threshold values. Yields from these plots were compared with plots scheduled by the farm manager. The highest yield was obtained by the computer model using evapotranspiration data taken from the local AZMET station; the plots scheduled by the infrared thermometer (using the low threshold value) ranked a close second.
Evaluation of Plant Growth Regulators on Wheat in Arizona, 1987Plant growth regulators are applied to small grains to decrease lodging which can adversely affect crop growth and yield. Wheat is intensively managed in Arizona, and lodging can be a problem. Chlormequat and ethephon were applied at various rates and times in six studies in 1987 to evaluate their use on Arizona's semi -dwarf cultivars with respect to lodging plant height, yield components and grain yield The results indicated that growth regulators applied at the recommended rates and times may decrease plant height and decrease kernel weight. However, the influence of growth regulator treatments on tiller number, head number, kernel number, and grain yield was not demonstrated. The ambiguous results obtained suggest our efforts need to be directed toward documenting the extent of lodging in the state, studying the effects of lodging and predicting when lodging will occur.
Effects of P Applications on Wheat Tissue Phosphate Levels and Grain Production in Graham CountyCollecting additional data to calibrate and refine current guidelines for interpreting soil and plant test values for P is an ongoing need in Arizona. An experiment was conducted at the Safford Agricultural Center during the 1987 -88 crop year to evaluate the response of 'Aldura' durum wheat to P fertilizer applications on a clay loam soil testing low in available P. Maximum grain yields of more than 5,500 lbs. /A were obtained by banding 40 lbs. P₂O₅/A as triple super phosphate with the seed at planting. A December 9 planting date subjected plants to cold soil temperatures early in the season (up to 80 days after planting), rendering soil P less available for plant utilization. Preplant soil P analyses predicted the yield increase observed with P fertilization (11.2 %);however, economic returns were not sufficient to offset the cost of P fertilizer. The recommended preplant soil test for P proved accurate in predicting P status and stem PO₄⁻P tissue analyses seemed reliable in monitoring P nutrition of durum wheat. A critical nutrient range of 1200 - 2000 ppm PO₄⁻P is proposed for basal stem tissue sampled prior to the joint growth stage, and 1500 - 1706 ppm PO₄⁻P is suggested for flag leaf tissue sampled at the boot stage.
Comparison of Residual Nitrate and Fertilizer Nitrogen Efficiency in Basin Irrigated WheatThe relative efficiencies of residual soil NO₃⁻N and fertilizer Nin basin - irrigated wheat production are not well defined. A two-year field study was conducted at the Safford Agricultural Center to investigate what these N efficiencies are under optimum yielding conditions. 'Aldura' durum wheat was grown on the same field site two years in succession. In 1987 a wide range of fertilizer N (0 to 419 lbs /A) applications resulted in residual NO₃⁻N accumulations of 36 to 140 lbs /A in the surface four feet of soil. Residual N plots were split in 1988 with one subplot receiving no additional N while the other was treated with 145 lbs of fertilizer N /A. Grain yield response curves for the –N and +N subplots were used to estimate the marginal rate of substitution (MRS) of soil NO₃⁻N for fertilizer N. The marginal efficiency of residual NO₃⁻N was a constant 16.7 lbs. grain produced /lb. of N across the range of profile N values in this study, while the marginal efficiency of fertilizer N varied from over 17 to below 6 lbs. grain /lb. N. When basin- irrigated wheat is supplied with adequate, but not excessive N, the MRS of soil vs. fertilizer N is about 1:1 although absolute N efficiencies under basin irrigation are considerably lower than those achieved in other grain production systems.
Evaluation of the Accuracy of a Wheat Stem Nitrate Test in Predicting Nitrogen Requirements of Irrigated Durum WheatThe procedure currently recommended by the University of Arizona for predicting the nitrogen (N) requirements of durum wheat has proven to be quite accurate at sites where grain yields exceeded 5,400 lbs/acre. However, the method slightly overestimated N needs when the yield possibility was below that level. Additional information on the relationships between N rates, stem NO₃⁻N levels and grain yields are needed for the wide range of agronomic conditions found in Arizona. Three N fertility trials were conducted at the Maricopa Agricultural Center to: 1) document the accuracy of the currently recommended soil + stem NO₃⁻N testing procedure in predicting the N needs of durum wheat on soils of varying residual N content and grain yield potentials; and 2) to evaluate the use of the current stem testing procedure on two durum varieties 'Aldura' and 'Westbred -881. The University of Arizona procedure was found to accurately predict the minimum amount of N required for optimum production of durum wheat on two sites where yield potentials were 5,400 and 4300 lbs. grain /A, but it slightly overpredicted N rates on two sites with maximum yield levels of 5,400 lbs /a. 'Aldura' consistently out yielded 'Westbred -881' by about 12 % but 'Aldura' also averaged 0.78 %lower in grain protein content. Little statistical or practical differences were observed in the quantities of NO₃⁻N contained in the stem tissue of these two varieties, which should simplify the interpretation of stem NO₃⁻N values for various wheat cultivars. The currently recommended procedure for predicting optimum N rates in durum wheat production has proven to be accurate when yield levels exceed 5,400 lbs. grain /A. A slight modification of the procedure may be needed to more closely predict N requirements on lower yielding sites.