Copper Deficiency in Cereal and Oilseed Crops in Northern Canadian Prairie Soils¹

Abstract

Transitional grassland/forest light soils in Saskatchewan are often deficient in Cu. The high cost of micronutrient fertilizers necessitates extreme care in identifying micronutrient deficiencies and selecting effective products and methods of application. Comparison of tissue and grain or seed analysis for spring wheat (Triticum ustivum L.), canola (Brassica napus L.), and flax (Linum usitatissimum L.) vs. DTPA-extractable soil Cu levels revealed that diagnosis of Cu deficiencies can more accurately be achieved via the latter. The critical DTPA-extractable Cu levels were 0.40 mg Cu kg-• of soil for spring wheat and 0.35 mg Cu kg-• of soil for canola and flax. A series of field experiments comparing different forms of soil and foliar Cu fertilizers were conducted on several transitional grassland/forest soils. Copper oxide applied in the spring was generally ineffective in the year of application but alleviated Cu deficiencies in the following year. Copper-sulfate (blue stone) and chelated products (polylignosulphonic acid) were effective in the year of application. However, the latter had no residual value at the rates of application used. This, combined with their extremely high current prices, makes them an undesirable Cu fertilizer source for the soils in the study area. Foliar Cu applications of either Co-sulfate or Co-chelate may be effective, but their performance has been erratic; hence, they should only be considered as an emergency measure for correcting of Cu deficiency.

Effectiveness of seed-soaked Cu, autumn- versus spring-applied Cu, and Cu-treated P fertilizer on seed yield of wheat and residual nitrate-N for a Cu-deficient soil

“…This suggests that dispersion and availability of Cu from the granules, especially from large granules , may be a major problem on farm fields. This also suggests that the lack of dispersion of Cu ions from granular Cu fertilizers and subsequently reduced Cu availability to crop plants can be overcome by application in the previous autumn (Karamanos et al 1986;Malhi et al 1989Malhi et al , 2005.…”

“…Previous field experiments on corn in Egypt have also indicated that use of corn seeds soaked in Zn, Mn and Fe solution could enhance NFUE leading to improvement in seed yield and N recovery (Teama 2001). However, it must be remembered that soil-applied Cu fertilizers at relatively high rates should have much longer-term residual effects on crop yield compared with foliar or seed-soaked Cu fertilizer treatments applied at low Cu rates (Gartrell 1980;Malhi et al 1989;Solberg et al 1996;Karamanos et al 1986Karamanos et al , 2005.…”

“…Les re´sultats montrent aussi qu'en trempant les graines dans de l'EDTA-Cu peu concentre´, on peut pre´venir la carence du ble´en Cu et augmenter son rendement grainier, mais moins que les autres traitements au Cu. Il est possible de minimiser l'accumulation et le mouvement vers le bas du N-nitrate re´siduel dans le sol en pre´venant la carence en Cu dans le ble´par l'application combine´e d'engrais Cu et N. Deficiency of Cu is not widespread in Saskatchewan or any other prairie province, but it can cause a considerable reduction in seed yield and quality of wheat when it occurs (Karamanos et al 1986Malhi et al 1989;Piening et al 1989). Wheat is one of the cereals most sensitive to Cu deficiency (McAndrew et al 1984;Alberta Agriculture, Food and Rural Development 1995;Solberg et al 1996), and Cu deficiency is often associated with coarse-textured soils (Kruger et al 1985).…”

“…Wheat is one of the cereals most sensitive to Cu deficiency (McAndrew et al 1984;Alberta Agriculture, Food and Rural Development 1995;Solberg et al 1996), and Cu deficiency is often associated with coarse-textured soils (Kruger et al 1985). Yield responses of cereals to Cu fertilization have been investigated (Karamanos et al , 1986(Karamanos et al , 2005Malhi et al 1989Malhi et al , 2005. Soil incorporation of granular Cu fertilizers at 3 to 5.6 kg Cu ha (1 has been suggested to prevent Cu deficiency in crops grown on Cu-deficient soils (Saskatchewan Agriculture and Food 2000).…”

“…(1 in spring was not effective in preventing Cu deficiency and improving crop yield in the year of application, but seed yield increased in the second year (Karamanos et al 1986). These findings suggest that the dispersion problem can be minimized by applying granular Cu fertilizers several months prior to seeding (i.e., possibly in the previous autumn).…”