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How a farmer should manage phosphorus nutrition for maize production in a farm


Date Posted: 10/15/2018 12:05:52 AM

Posted By: jim items  Membership Level: Gold  Total Points: 2112

Phosphorus is one of the main macro-nutrient that plays a number of of roles in plants. It’s a component of nucleic acids which plays a key role in plant reproduction of which grain production is an important result. It is critical in biological energy transfer processes efficient for life and growth. Adequate phosphorus leads to higher grain production, improved crop quality, greater stalk strength, increased root growth and early crop maturity.

The farm manager needs to consider the possible side effects in maize crop production result of erosion specifically the phosphorus nutrient pollution of the underground water or other surface water in a maize crop field. Water can be polluted with phosphorus primarily as a result of erosion and runoff of manure, fertilizer. The amount of phosphorus lost due to runoff of manure, fertilizer or soil may be relatively small as far as fertilizer costs are concerned.

Maize production requires a slightly acidic soil condition hence the pH 5.The slight acidity in the soil arises from the application of phosphate fertilizers and manure in the soil where excess phosphorus reacts with water to form weak phosphoric acids. Due to this requirement of the maize plant during growth, an optimum phosphorus level availability within the soil should be maintained as well. For this to be achieved the farmer should manage the source of phosphorus supply into his or her farm. This promotes a balance between supply and crop uptake of phosphorus.

Soil management attempts to minimize the buildup of phosphorus in the soil above levels sufficient for optimum growth of a maize plant. This is because the buildup of phosphorus within the soil can interfere with the normal growth rate of maize. This source management is achieved by controlling the quantity of phosphorus in manure and the amount of phosphate fertilizers that

is applied in a maize crop field. For this to be achieved several techniques has to be followed and put in place. These techniques are as discussed below:

A farmer should consider the ability of the soil in phosphorus supply. The soil solution is the key to plant nutrition because all phosphorus that is taken up by plants have to come from phosphorus dissolved in the soil solution. Since the amount of soluble phosphorus in the soil is very slow it must be replenished as many times during a growing season to meet the nutritional needs of a maize crop. The bulk of the soil phosphorus is always either in the soil minerals or the organic matter.

Use of composting method of farm manure application should be considered as a better management tool to improve manure distribution in a maize crop field. This is because the soil organic matter and minerals only contain stable phosphorus in unavailable forms thus needed to be supplied with manure for readily fixed phosphorus to the plants roots. Although composting tends to increase the phosphorus concentration from the manure in the soil, it reduces the volume and thus evenly distribution of phosphorus as a macro-nutrient requirement by the maize crop. Composting ensures uniform spread of manure at more accurate rates.

Phosphorus applications at recommended rates can reduce phosphorus loss by surface runoff and to some extent leaching due to increased crop uptake. Nevertheless, its of vital importance that we implement management practices that minimize phosphorus build up in excess of maize crop requirement.

The farm manager should also continuously carry out soil testing as a management tool in phosphorus management for maize crop production. Soil testing will help reveal the soil pH, the soil phosphorus level and determines the recommended application amount of phosphorus to a maize crop field. Sampling depth should also be considered as it is of importance for both pH and phosphorus especially if in a reduced and no tillage systems where there is little or no mixing to homogenize the soil. All this are done to ensure that extraction of phosphorus between 30 and 50 parts per million which is the requirement for optimum maize production.

Another factor the farmer should consider is the interactions between phosphorus and other nutrients that can affect maize crop production. Once the ratio of phosphorus to zinc in a soil becomes excessively high, a phosphorus induced zinc deficiency may result thus limiting the maize yields. Therefore, phosphorus induced zinc deficiency is usually only seen when excessive soil phosphorus level are due to phosphorus fertilizer and not manure.

The other main factor that a farmer should consider is the placement of phosphorus in a maize crop field. This is mainly because of phosphorus immobility and soil fixation which determines its availability to maize plants. On soils with optimum to high levels of phosphorus banding has more advantage than broadcasting in maize field rather than broadcasting. This ensures uniform mixing of soil and phosphorus thus high probability of root contact with the fertilizer becomes maximized.

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