Plant nutrition and pest control

摘要

Dr Terry Mabbett looks at the application of copper in support of safe and effective crop production. COPPER'S ROLE IN agriculture is fundamental. This metallic element as the copper ion is an essential micronutrient or trace element for plant growthand development and an essential mineral in livestock nutrition, without which proper growth and development is inhibited. Insufficient copper in the nutrition of crop plants and farm animals will lead to the development of deficiency symptoms. Copper deficiencies in the soil can be corrected by the application of copper salts or copper chelates, and the extent to which they are used as part of an overall plant fertilizer programme depends on the copper status of the soil and the responsiveness of the crop in question. Copper is held strongly by soil organic matter that plays a key role in determining the availability for root uptake and plant growth. Exchangeable copper is held very tightly on clay minerals and leaching is negligible except from sandy soils. Histosols, podzols, arenosols, solonetz and kastanozems are soil types that are likely have low copper levels. Crops generally regarded as being responsive to applications of copper include maize, wheat, rice, sorghum and citrus.