Effect of copper on stem melanosis and yield of wheat: Sources, rates and methods of application

Abstract

Park wheat (Triticum aestivum cv. Park) is susceptible to stem melanosis when grown on Cu-deficient soils. Three field experiments were conducted to evaluate the effectiveness of various Cu sources, using different methods and rates of application for reducing the incidence of stem melanosis and increasing the grain yield of Park wheat on a Cu-deficient Black Chernozemic soil in central Alberta. A fourth experiment determined the residual effect of Cu over 4 years. In the first experiment, Park wheat had less disease and higher grain yield when Cu-chelate solution at 2 and 4 kg Cu ha-~ or Cu-sulfate solution at 10 and 20 kg Cu ha-I was applied to the soil surface and incorporated to a depth of 8 cm or was applied at these rates as a foliar spray. The foliar application, however, was phytotoxic and delayed maturity by approximately two weeks. Sidebanding Cu (4 cm to the side and 4 cm below the seed row) was least effective. In the second experiment, Cu-sulfate solution incorporated into the soil was more effective than the soil incorporated granular Cu-sulfate in reducing disease incidence and increasing grain yield in the year of application. In the following year the granular Cu was as effective as solution Cu. The third experiment showed that Cu seed dressings did not have any effect on disease incidence or grain yield of Park wheat. In the fourth experiment, the residual effect of Cu-chelate was evident four years after application. The grain yield in the fourth year was about four times that of the control.

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

“…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.…”

“…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.…”

“…Residual Nitrate-N in Soil Previous research has shown that Cu deficiency and other micronutrients in soil can cause serious reductions in seed yield and utilization efficiency of applied N (kg seed yield per kg of applied N) because of significant N )micronutrient interaction (Antil et al 1988;Sakal et al 1988;Malhi et al 1989Malhi et al , 2005Teama 2001). The inefficient use of applied N from low crop yield and N uptake due to deficiency of other nutrients in the crop can result in the accumulation of large amounts of nitrate-N in the soil, and increase the potential for leaching and other gaseous N losses, especially in early spring after snow melt (Nyborg et al 1990(Nyborg et al , 1997Heaney et al 1992) and, consequently, contamination of ground water (Fan et al 2003;Zhang et al 2004).…”

“…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).…”