Effectiveness on Soil and Foliar Applied Micronutrient Mixes Rigas E. Karamanos, Norm A. Flore and John T. Harapiak Western Co-operative Fertilizers Limited, P.O. Box 2500, Calgary, AB T2P 2N1 Abstract Use of micronutrient mixes is often promoted as a means of alleviating micronutrient deficiencies or simply providing a balanced nutrition to crops. We carried out ninteen experiment with, twenty-nine with and five with canola from 1989 to 1994 to ascertain whether targeted or non-targeted use of micronutrient mixes provide an effective means of alleviating micronutrient deficiencies or simply increase yield due to a balanced nutrition. Two commercially available products were used, one for soil and one for foliar applications. The product for soil application was banded, broadcast and incorporated or seedplaced in five experiments with and. There were no statistically (P<0.05) yield increases with any of the uses of this product. Foliar applications of the other product, on the other hand, resulted in a number of significant increases, namely, in four of nineteen experiments with, in eight of twenty-seven experiments with and in two of five experiments with canola. None of these responses could provide an economic return or be predicted based on either soil tests or targeted yields. Introduction Micronutrient deficiencies in prairie soils are known to occur on transitional soils with low organic matter and alkaline ph (Karamanos 1997a,b; Karamanos et al. 1985b, 1986; Kruger et al. 1984; McGregor 1972; Penney et al. 1988; Singh et al. 1987) and organic (peat) soils (Karamanos et al. 1985a, 1991; Reid 1982). Identification of micronutrient deficiencies and management practices to alleviate these deficiencies are discussed elsewhere in these Proceedings (Karamanos, 2000). A number of either soil or foliar applied multi-micronutrient products that are extensively used in other parts of the world have penetrated the western Canadian market based on the premise that their use aids a holistic approach to growing crops. Further claims address an optimum balance of all nutrients and especially micronutrients in achieving maximum yields. Indeed an optimum balance of applied nutrients may be of extreme importance in many parts of the world but very little information does exist for western Canadian conditions. Therefore, a series of experiments were carried out to ascertain whether targeted or non-targeted use of micronutrient mixes: 1. Provides an effective means of alleviating micronutrient deficiencies; 2. Provides a balanced nutrition, therefore, leads to yield increases. Materials and Methods Two products were selected for the study because of their availability in western Canada (Table 1).
Table 1. Micronutrient content and method of application of the mixes used in the study. Mix Constituents Method of application Stage of application Rate of application 1 Cu 0.15% B 0.08% Foliar Cereals: Tillering 5 to 8 Fe 0.10% Mo 0.0005% and Boot stage lb/acre each Mn 0.10% Zn 1.00% Canola: Spiking and early flowering application 2 Zn 18% Fe 4% Soil Spring seed-row 12 lb/acre Mn 8% B 2% Cu 4% S 8% All experiments were carried out between 1989 and 1994 at various locations in Alberta representing the majority of agroecological environments found in western Canada. In total, forty-seven experiments involving micronutrient mixes were carried out. Experimental designs were organized in three main categories (Tables 2 to 4) based on the primary nutrient investigated in each of the experiment. In all case, micronutrient applications were incorporated as a sub-treatment of the main treatment(s). Table 2. Group of experiments with nitrogen rates and placement as main treatments and micronutrient mixes as sub-treatments. Design Brief Description Crop Number of experiments 1 Treatments: Control, 0, 36, 72, 108, 144, Wheat 3 180 lb N/acre Barley 11 Fertilizer rates: P2O5 seed-row applied at one rate of 27 lb/acre as 0-45-0 Canola 2 2 Treatments: Control, 0, 36, 72 and 108 lb N/acre plus soil applied mix at 12 lb/acre Fertilizer rates: P2O5 seed-row applied at one rate of 27 lb/acre as 0-45-0 3 Treatments: Urea, Ammonium Nitrate or Calcium Nitrate banded at 54 lb N/acre Fertilizer rates: P2O5 seed-row applied at 27 lb P2O5/acre Sub-total 16 Wheat 2 Barley 2 Sub-total 8 Barley 1 Wheat 1 TOTAL 26 Soil samples were obtained from every site and were analyzed for routine soil characteristics as well as macro and micronutrient levels (Enviro-Test Laboratories routine methodology). Where different crops were involved on the same site, samples were obtained from the corresponding portion of the field.
Table 3. Group of experiments with phosphorus rates as main treatments and micronutrient mixes as sub-treatments. Design Brief Description Crop Number of experiments 1 Treatments: Control, 13, 27, and 40 lb Wheat 5 P2O5/acre Barley 8 Fertilizer rates: N banded as urea at 72 or 108 lb N/acre Canola 2 2 Treatments: Control, 9, 18, and 27 lb P2O5/acre Fertilizer rates: N banded as urea at 72 or 108 lb N/acre Sub-total 15 Canola 1 TOTAL 16 Table 4. Group of experiments with methods of soil copper application as main treatments and micronutrient mixes as sub-treatments. Design Brief Description Crop Number of experiments 1 Treatments: Control, Granular chelated Wheat 4 copper band, broadcast or seed-row Barley 1 applied at 2 lb Cu/acre Fertilizer rates: N banded as urea at 72 lb N/acre, P2O5 seed-row applied at 27 lb P2O5/acre and K2O banded at 27 lb K2O /acre TOTAL 5 All results were subject to analysis of variance utilizing SYSTAT 8.0 and, where appropriate means were separated by the least significant difference (LSD) at P<0.05. Results and Discussion Application of micronutrient mixes to, and canola crops resulted in yield increases in nine of twenty-five, two of nineteen and two of three cases, respectively. Responses varied from 4.6 to 11 bu/acre for, 3.2 to 6.1 bu/acre for and 3.9 to 5.5 bu/acre for canola. These responses corresponded to a 4.5 to 10, 4.5 to 12 and 8 to 12 percentage increase in, and canola yield. Significant (P<0.05) yield increases were obtained with the foliar applications only. Responses organized on a per site basis are presented in Figures 1 through 5. Yield increases could not be attributed to any particular micronutrient, however, soil test values at the Lethbridge sites might suggest a response to zinc (Zn). Where copper (Cu) deficiency was suspected based
on existing soil testing criteria (Karamanos, 2000), no responses were obtained when only Cu was applied in chelated form. 130.0 110.0 90.0 70.0 with Foliar Significant at P<0.01 without soil applied with soil applied e Year Cu Fe Zn Mn B 1989 1.3 115 10 39 2.1 1990 0.8 127 12 26 1.6 0.48 Tobin 0.85 Tobin 1.20 1 $2.00/bu and $5.00/bu canola canola 50.0 Virden B917 Tobin Horizon Tobin Figure 1. Responses of and canola to foliar and soil applied micronutrient mixes at Bentley, Alberta. 110.0 with Foliar Significant at P<0.05 without soil applied with soil applied Year Site Cu Fe Zn M n B 1989 1.1 70 2.8 54 0.8 1.0 73 2.8 44 0.8 1990 1.0 71 2.8 48 0.8 0.9 77 2.8 55 0.8 1991 0.8 74 2.6 35 0.7 1.0 75 2.8 40 0.8 0.39 0.44 90.0 70.0 Roblin 1.07 1 $2.00/bu and $4.00/bu 50.0 30.0 Winthrope B1602 B1602 Figure 2. Responses of and canola to foliar and soil applied micronutrient mixes at Irricana, Alberta. Roblin Roblin Non-targeted application of micronutrient mixes at all sites to provide a balanced nutrition of crops proved both agronomically inefficient and economically nonviable under western Canadian conditions. Yield increases were both small and unpredictable even when exceptionally high yields were obtained (Figures 1 through 5).
95.0 90.0 Year Cu Fe Zn M n B 1991 1.2 125 4.2 64 0.7 0.56 1 $4.00/bu 85.0 75.0 70.0 Yield w ithout Foliar Yield w ith Foliar with Foliar Significant at P<0.05 65.0 Figure 3. Responses of and canola to foliar and soil applied micronutrient mixes at Airdrie, Alberta. 200.0 1 1 1 Significant at P<0.05 without soil applied with soil applied Site Cu Fe Zn Mn B Lethbridge 1.6 96 0.7 19 1.0 Coaldale 1.4 44 0.6 60 1.3 B1602 0.67 B1602 0.96 Tempest 0.53 1 $2.00/bu B1602 B1602 Tempest Fielder AC Reed Fielder AC Reed Tempest Figure 4. Responses of and canola to foliar and soil applied micronutrient mixes in the Lethbridge, Alberta area. Conclusions 1. Micronutrient mixes do not afford an economical means of correcting micronutrient deficiencies. 2. Western Canadian soils provide crops with a balanced nutrition without the aid of a micronutrient mix.
1 1 Yield Yield with Foliar Significant at P 0 01 Site Cu Fe Zn M n B Olds 1.2 32 0.5 10 0.7 Camrose 1.0 98 1.6 18 0.9 Lacombe 1.1 81 4.0 43 1.5 Crossfield 1.8 74 2.0 12 0.5 Wetaskiwin 1.0 148 6.6 59 2.0 Calgary 3.9 100 6.9 43 1.2 0.69 B1602 0.55 1 $2.00/bu Samson B1602 Figure 5. Responses of and canola to foliar and soil applied micronutrient mixes in Central Alberta. Park Park References Karamanos, R.E. 1997a. Site Specific Management of Micronutrients. Proceedings. Intensive Wheat Management Conference, 34-40, Potash and Phosphate Institute, Brookings, SD. Karamanos, R.E. 1997b. Micronutrient fertility in the prairies. Proceedings Western Canada Agronomy Workshop, 94-105, Canadian Fertilizer Institute of Canada, Ottawa, ON. Karamanos, R.E. 2000. Micronutrient Fertilizer Practices in Saskatchewan Update 2000, Proc. Soils and Crops 2000, University of Saskatchewan, Saskatoon, SK. Karamanos, R.E., J.G. Fradette and P.D. Gerwing, 1985a. Evaluation of Copper and Manganese Nutrition of Spring Wheat Grown on Organic Soils. Can. J. Soil Sci., 65, 133-148. Karamanos, R.E., G.A. Kruger and J.W.B. Stewart, 1985b. Micronutrient Fertilizer Practices in Saskatchewan. Proceedings. 1985 Soils and Crops Workshop, 177-189, University of Saskatchewan, Saskatoon, SK. Karamanos, R.E., G.A. Kruger and J.W.B. Stewart, 1986. Copper Deficiency in Cereal and Oilseed Crops in Northern Canadian Prairie Soils. Agron. J., 78, 317-323. Karamanos, R.E., G.A. Kruger and J.P. Singh, 1991. Manganese and Copper Interaction in Barley Grown on Organic Soils. Comm. Soil Sci. Plant Anal., 22, 1397-1408. Kruger, G.A., R.E. Karamanos and J.P. Singh, 1984. The Copper Fertility of Saskatchewan Soils. Can. J. Soil Sci., 64, 89-99. McGregor, W.R. 1972. A study of the copper and zinc status of some Manitoba soils. M.Sc. Thesis, Department of Soil Science, University of Manitoba, Winnipeg, MB. Penney, D.C., E.D. Solberg, I.R. Evans, and L.J. Piening. 1988. The copper fertility of Alberta soils. Proceedings Great Plains Soil Fertility Workshop, Vol. 2, Kansas State University, Manhatten, KS. Reid, J.M. 1982. Availability of manganese and effects of soil temperature on availability of manganese to plants grown on organic soils, M.Sc. Thesis, Department of Soil Science, University of Manitoba, Winnipeg, MB. Singh, J.P., R.E. Karamanos and J.W.B. Stewart, 1987. Zinc Fertility of Saskatchewan Soils. Can. J. Soil Sci., 67, 103-116.