Sign up for email alerts of new Fluid Journal issues!
Fluid Journal : Fluid Journal 1993-1995
3 Fluid Journal Spring 1994 not significantly affected (P ---0.10) at any site; however, the eight-site average response was 2 bu/A, suggesting that a slight positive response may have occurred. Data were generated by requesting that growers using starters leave check strips in their fields. Growing conditions in 1988 were generally abnormally hot early in the season and dry later. Potatoes In Florida (1980-81) Locascio and Rhue examined the effects of starter P sources and micronutrients on potato growth and marketable yield. Adding Cu, Fe, Mn, Zn, B, and Mo did not increase yield over treatments without micronutrients. Soil. To evaluate the effects of four P sources and four micronutrient sources on yield, potatoes were grown at two sites consisting of St. John's fine sandy loam soils. P source. Phosphate sources were liquid ortho-P (10-34-0), liquid poly-P (10-34-0), dry diammonium phosphate (DAP 18-46-0), and dry triple super phosphate (TSP 0-46-0). The starters were formulated as 8-18-9 (percent N, P205, K2O). Placement/rate. The starters were applied in two bands, three inches to the side of the bed center and two inches below the seed piece level at the rate of 1,000 lbs A. Approximately six weeks later, the crop was sidedressed at a rate of 80 lbs/A nitrogen and 80 lbs/A potassium. Banding was on one side of the bed, ten inches from the bed center. Irrigation supplemented rainfall. Phosphate application significantly increased potato tuber yields in both seasons. Soil P tests on the experimental site predicted a positive yield response. Average yield responses to the different phosphate sources are shown in Figure 3. As can be seen, marketable potato yields were highest with liquid poly-P and lowest with DAP. Sugar beets Research by Smith (1983-84) in Crooks-ton, Minnesota, examined the effects of starters on sugar beet yield and quality. Starters used were 9-18-9 or 10-34-0 at rates varying from 3 to 12 gal/A. Largest yield increase over check was 3.6 tons/A, using 10-34-0 at rate of 6 gal/A. Studies in previous years showed mixed results. Environmental conditions after planting had a large influence on the response. The Crookston study produced the following trends over its six-year duration: 1) final yield increased significantly two out of six years, 2) salts over 5.5 lbs/A reduced stand, and 3) starter increased early-season growth and vigor five out of six years. The researcher concluded that reducing applied nitrogen may trigger better early-season growth and vigor due to starters. Dr. Fixen is North Central director for the Potash & Phosphate Institute, Brookings. SD and Dr. Lohry is agronomist/br NutraFlo Company in Sioux City, IA. !
Fluid Journal 1996-1998