Copper (Cu) – Copper

Types of soil Cu:

                     – Cu²⁺ in solution

                     – Large amounts of Cu²⁺ complex with organic matter – more than any other trace elements

                     – The solubility of Cu²⁺ minerals is relatively low: 10 – 6 – 10 – 8 M

                     – pH dependent activity

                     – Strong absorption on the oxide minerals

                     – Some are adsorbed on the CEC

                     – Chelates are important components to maintain Cu content in solution and move to roots

                     – Interactions: N, P, Fe, Zn high decrease the usefulness of Cu²⁺

                     1. The impact of copper on the physiological biochemistry of plants:

                      Copper affects many biochemical physiological processes of plants such as N-fixation, nitrification, decomposition, CO₂ reduction, synthesis of synthetic chlorophyll growth regulators, Glucose metabolism, new plant stem stems, and drought tolerance, cold tolerance and heat tolerance.

                       Copper affects the synthesis of many types of carbohydrates, proteins, fats, chlorophyll and other pigments, vitamin C and enzymes.

                       Expression of copper deficiency in plants:

                        Lack of copper lost the green leaf veins, leaves are often wilt, easy to fall

                        Deficiency of copper, yellow spots and curly leaf appear, the tip of the leaf turns white, the number of flowers formed is less restricted, weak plants are susceptible to fungal attack.

                        Copper-deficient phenomena are common for rice plants that cause white-on-white and non-pollinated cotton buds (rice straw head), but not much cotton and appear in other plants.

                        Nitrogen fertilization has led to the occurrence of copper deficiency, which reduces yield and grass quality. Applying multiple times also reduces the copper content and citrus output.

                       Expression of excess copper (copper poisoning)

                                                        The plant grows slowly and leaves in 8 mM copper solution, 12 mM

                       Excess copper is very toxic to sweet potatoes, at low concentrations of 5 mM in the root zone sufficiently to significantly slow down plant growth. If concentrations higher than 20 mM roots stop growing, Damage can lead to severe wilting. Unlike zinc poisoning, there are few or no leaves in the leaves, nor red pigmentation.

                                                   Copper botulism occurs in the area of he midribs of mature leaves (J. O’Sullivan).

                                                              The effect of frequent use of copper-based fungicides

                      Similar to the toxicity of manganese and zinc, copper toxicity can also cause symptoms of iron deficiency.

                      Copper in the soil.

                      Since 1931 it has been found that the new plant has good development. Gradually, it was found that plants grown on peat soils, rich in organic matter, lacked copper. Recently the phenomenon of copper deficiency has appeared on many other soil types.

                      Easy-to-digestible copper is often found in the soil and is usually introduced into the soil through fertilizer and fungicides. The amount of copper in the soil depends on the parent rock and the amount of Cu in the soil increases through the accumulation of biopesticides (Cu²⁺ from deep layers up to the ground). The amount of Cu²⁺ in the soil varies with the amount of organic matter. Organic matter in the soil varies with the amount of organic matter. Organic matter in the soil combines with co-copper complexes – organic plant difficult to use.

If in the soil N and S high, the copper – humus complex as durable. Lightning can also absorb copper ions, although the absorption is weaker. Organic soil is rich in lightning, and copper deficiency is more likely to occur. In our country the mountain valley, coastal muddy land, peat soils, organic rich alum soils can be the phenomenon of lack of copper.

                    Studies show that when soil pH increases, the amount of available copper decreases. So lime improvement acidity can easily lead to the phenomenon of lack of copper.

                    It has also been found that there is a negative relationship between the amount of Al and the readily available copper. When the content of Al increases, the plant attracts less. There is also a similar relationship between copper and iron.

                    Acidic soils, more iron, aluminum aluminum, the more likely they are to be copper.

                    2. Types of raw materials used for the production of copper dung

                    There are two main groups:

                     Water-soluble compounds: Copper sulfate water (CuSO₄.H₂O), 35% Cu in the form of powder or pellets. Copper sulphate with 5 molecules of water (CuSO₄.5H₂O) has a Cu ratio of 25% in the form of powder or pellets. Copper complex (Cu.EDTA) in the form of powder or pellets contains 15% Cu. CuSO₄.5H₂O and Cu-EDTA

                    + Citric acid soluble compounds: Copper (II) oxide (CuO) containing 75% Cu, copper (I) oxide (Cu₂O) containing 89% Cu; copper sulphate (CuSO₄.3Cu(OH)₂.2H₂O) containing 53% Cu in the form of powder or pellets; Copper silicate in the form of glass (copper silicates) in powder form; Copper ammonium salt contains 30% copper.

CuO and Cu₂O

                      + The above compounds may be used directly as fertilizer or in the production of copper-bearing multipurpose fertilizers. Cu pyrite containing 0.3 – 0.6% Cu is also used as a raw material for the production of copper-containing polymers containing sulfur or for direct fertilization.

                     Use copper fertilizer:

                    Copper available for copper deficiency can be provided in two ways:

                    + Use spray solution on the leaves. Copper salts dissolved in water are mixed with a concentration of 0.02 – 0.05% CuSO₄ sprayed from 600 – 1000 liters per hectare, or soaked seeds within 6 -12 hours before sowing.

                    Use copper-insoluble salts only dissolved in citric acid such as copper oxide and silicates, ammonium phosphate salts. The amount of fertilizer equivalent to 10 – 25 kg Cu/ha.

                     Cu fertilizer for years easy to accumulate and poison. Many of the vineyards using boron (sulfate-lime mix) over many years to eradicate the disease have accumulated many copper to the level of copper toxicity. Vegetable gardens often use copper insect pesticides also often occur overwhelming copper poisoning.

                     Copper excess often causes iron deficiency and zinc deficiency and is associated with the supply of N and Mo. Creating a balance between Cu, Fe, Zn, Mo and N is a prerequisite for the prevention of toxicity due to overexposure. That is also the basis of the technique of using the combination of micronutrients.