Molybdenum (Mo), boron (B), and iron (Fe) play an important role in symbiotic nitrogen fixation by legume plants. The intensity of this process varies in different growth stages of legumes, and the changes are accompanied by changes in the content and translocation of these micronutrients in the plant. A two-year field experiment was conducted to investigate the dynamics of molybdenum, boron, and iron content, translocation, and accumulation in pea plants. Two pea cultivars were studied in six stages of growth, from the four-leaf stage to full maturity. The content of Mo, B, and Fe in the roots of pea was highest from the four-leaf stage to the full flowering stage, i.e., the period of establishment of symbiosis and the most intensive atmospheric nitrogen fixation. The bioaccumulation factors of Mo and Fe were generally highest in the initial stages of pea growth and decreased during generative development, while the reverse pattern was observed for boron. The bioaccumulation factors also indicate high bioaccumulation of Mo and B and low bioaccumulation of Fe in the biomass of pea. The translocation factor indicated a high potential for allocation of Mo from the roots to the aerial parts, increasing during growth; high and stable potential for allocation of boron; and very minor allocation of iron to the aerial parts. The values of all parameters tested were usually dependent on the conditions in which the experiment was conducted (the year), but not on the cultivar of a pea.

The sources of nitrogen for yellow lupine and spring triticale in their intercropping | Andrzej Wysokiński, Beata Kuziemska | Agricultural Journals

Copper is a microelement involved in the metabolism of nitrogen compounds in plants. Good utilization of nitrogen from soil and fertilizers by plants requires an adequate supply of copper. The aim of the study was to determine the effect of increasing levels of copper (100, 200, and 300 mg Cu·kg⁻¹ of soil) applied together with various organic fertilizers (cattle manure, chicken manure, and spent mushroom substrate) on nitrogen content and uptake by cocksfoot (Dactylis glomerata L.) and the coefficient of nitrogen utilization from organic fertilizers. The pot experiment was carried out in three growing seasons (May–September) in greenhouse, and in this cocksfoot was grown and harvested four cuts in each year. Copper and organic fertilizers were applied once in the first year before sowing cocksfoot, and the after-effect was investigated in the second and third years. Application of different amounts of copper did not influence the nitrogen content in the biomass of cocksfoot. At the same time, soil application of this micronutrient in the amount of 100 mg Cu∙kg⁻¹ of soil caused an increase in nitrogen uptake in the biomass of cocksfoot. Application of 100 and 200 mg Cu·kg⁻¹ of soil caused an increase in the coefficient of nitrogen utilization from the organic fertilizers, which was highest effect in the case of cattle manure. All of the organic materials used increased the content of nitrogen and its uptake by cocksfoot, but the greatest effect was noted following application of chicken manure. The study showed no synergistic or antagonistic relationships between copper and nitrogen.

Different content of Zn in the soil and organic fertilization can affect micronutrient uptake by plants. A pot experiment was carried out to determine the impact of increasing Zn application rates, i.e., 200, 400 and 600 Zn mg·kg⁻¹, in combination with bovine and chicken manures and mushroom substrate on Cu and Ni content, uptake and bioaccumulation factor in cocksfoot (Dactylis glomerata L.). Control objects without Zn and organic fertilizers and after application of only different Zn doses and only organic fertilizers were also tested. Application of Zn at 400 and 600 mg·kg⁻¹ significantly decreased the content, uptake and value of bioaccumulation factor of Cu in the grass. Different Zn doses were not found to influence the content and bioaccumulation factor of Ni in cocksfoot, but application at 200 Zn mg·kg⁻¹ increased Ni uptake. Chicken manure increased the content and bioaccumulation factor of Cu and Ni in the test plant, and all the organic fertilizers increased their uptake. Cocksfoot showed no tendency to excessive bioaccumulation of Cu and Ni.

Copper is an element necessary for the proper growth and development of plants, but when taken in excess amounts, it can be toxic. Its availability for plant can be reduced by using organic fertilizers or soil liming. The aim of the study was to investigate the effect of increasing doses of copper (100, 200, and 300 mg Cu·kg⁻¹ of soil) application in combination with various organic amendments (cattle manure, chicken manure, and spent mushroom substrate) on the yield of cocksfoot and its content and uptake of this metal, and to determine its coefficient of bioaccumulation and tolerance indices. The toxic effect of copper manifested by significant decrease in the yield of the test plant was after the application of 300 mg·kg⁻¹ of soil. Increasing doses of copper application increased its content and uptake by the test plant, while observing the decreasing bioaccumulation factor. All the soil amendments reduced the toxic effect of copper on cocksfoot. The most effective organic amendment in terms of yield and protective effects against high levels of copper was cattle manure, in the case of which the Org/Cu and Cu/Org tolerance indices were highest.

Zinc is essential for the growth and development of plants, but in excessive amounts in the soil it can be toxic for them. Its mobility depends in part on the organic matter content of the soil. The aim of the study was to investigate the effect of application of increasing amounts of zinc (200, 400 and 600 mg Zn·kg⁻¹ of soil) together with various forms of organic fertilizer (cattle manure, chicken manure and spent mushroom substrate) on the yield of cocksfoot and the content and uptake of this metal, and to determine its bioaccumulation factor and tolerance indices. A minor effect of zinc on cocksfoot, expressed as a decrease in yield, was observed following the application of 400 mg Zn·kg⁻¹ of soil. Increasing application to 600 mg Zn·kg⁻¹ caused a significant decrease in yield. Application of 400 and 600 mg Zn·kg⁻¹ of soil significantly reduced the value of the Zn/Org tolerance index. Increasing levels of zinc application increased its content and uptake by cocksfoot and reduced the bioaccumulation factor in the plants. All of the organic materials applied increased the yield of cocksfoot and its uptake of zinc. Spent mushroom substrate increased the Zn/Org tolerance index, while cattle manure and chicken manure increased the Org/Zn tolerance index, which confirms their protective action against high zinc content in the soil.