CHAPTER ONE

Introduction

1.1. Background of the study

Agriculture is a cardinal sector in the economy of any nation. Fertilizer application has over the period been essential in the effective growth of agricultural output. The importance of fertilizer in agriculture cannot be over emphasized; in other to effectively feed the nation and have enough to export, then understanding the importance of fertilizers is paramount. Fertilizers where effectively used from the 19th century in the world to grow crops amongst other things. There are basically two major types of fertilizer viz:

• Organic fertilizer
• Inorganic or synthetic fertilizers

These types of fertilizers have overtime help in boosting agricultural output in Nigeria and by extension help to boost our gross domestic product (GDP).

The nutrients required for healthy plant life are classified according to the elements, but the elements are not used as fertilizers. Instead compounds containing these elements are the basis of fertilizers. The macronutrients are consumed in larger quantities and are present in plant tissue in quantities from 0.15% to 6.0% on a dry matter (DM) (0% moisture) basis. Crops are made up of four main elements: hydrogen, oxygen, carbon, and nitrogen. Carbon, hydrogen and oxygen are widely available as water and carbon dioxide. Although nitrogen makes up most of the atmosphere, it is in a form that is unavailable to plants. Nitrogen is the most important fertilizer since nitrogen is present in proteins. To become nutritious to plants, nitrogen must be made available in a "fixed" form. Only some bacteria and their host plants (e.g. legumes) can fix atmospheric nitrogen (N2) by converting it to ammonia. Phosphate is required for the production of DNA, the main energy carrier in cells, as well as certain lipids.

Micronutrients are consumed in smaller quantities and are present in plant tissue on the order of parts per million (ppm), ranging from 0.15 to 400 ppm DM, or less than 0.04% DM. These elements are often present at the active sites of enzymes that carry out the plant's metabolism. Because these elements enable catalysts (enzymes) their impact far exceeds their weight percentage. Nitrogen being one of the most important nutrients needed for effective crop growth has prompted the effect of the NPK fertilizer on crop growth.

Nitrogen phosphorous potassium (NPK) fertilizer

The agriculture industry relies heavily on the use of NPK fertilizer.  There are various nutrients that plants need for healthy and effective growth. Soils often lack these elements, either naturally, or as a result of over cultivation or depletion, and needs to have these nutrients into it.

NPK fertilizer is primarily composed of three main elements: Nitrogen (N), Phosphorus (P), and Potassium (K), each of these being essential in plant nutrition and growth. Among other benefits, Nitrogen helps plants grow quickly, while also increasing the production of seed and fruit, and bettering the quality of crops. Nitrogen is also a component of chlorophyll, the substance that gives plants their green color, and also aids in photosynthesis which is the most important process in every crop development as a lot depends on how well a plant photosynthesizes.

Phosphorus, also a key player in the photosynthesis process, plays a vital role in a variety of the things needed by plants. Phosphorus supports the formation of oils, sugars, and starches.

Potassium, the third essential nutrient plants demand, assists in photosynthesis, fruit quality, the building of protein, and the reduction of disease.

While these three elements only scratch the surface of healthy plant nutrition and growth, they are the main nutrients required in the development of healthy, productive plants.

1.2. Aims and objectives of the study

• To know the effect of fertilizer on crop growth.
• To compare the crops fertilized with NPK with those not fertilized.
• To know the optimum quantity of fertilizer needed for effective growth of crops.
• To know the best combination of the NPK fertilizer required for healthy growth of crops.

1.3. Statement of the general problem

The decline of agricultural output which has made Nigeria to turn from a major agricultural exporter to a country that imports agricultural goods has prompted this research with a view to boosting our agricultural products by monitoring the effect of the NPK fertilizer on our crops.

Nigerian farmers especially the rural ones have always encountered problems on the best quantity and combination of these fertilizers that would increase their crop yield, the need to advice these teeming farmers has prompted us into this research.

1.4. Significance of the study

The findingsfrom this study seeks to educate the rural farmers on the best combination and quantity of the NPK fertilizer to be used so as to achieved increase  in their agricultural output and at the same time avoid over application of this fertilizer thereby minimizing cost.

1.5. Scope of the study

The scope of this study is on the effect of NPK fertilizer on crop growth using the federal university of agriculture Umuahia, Abiastate as a case study.

1.6. Limitation of the study

A major limitation of this study is on the retrieval of data as most of the crops under study died thus giving rise to missing values but these missing values were not statistically significant enough to affect the outcome of the study.

1.7. Research questions

1. What is NPK fertilizer?
2. What is the best combination of NPK fertilizer that would be best for a healthy growth of crops?
3. What is the optimum quantity of NPK fertilizer that can be used on crops?

1.8. Research hypothesis

H0: there is no significant effect of NPK fertilizer on crop growth.

H0: there is a significant effect of NPK fertilizer on crop growth.

1.9. Definition of terms

Fertilizer: a chemical or natural substance added to soil or land to increase its fertility.

NPK fertilizer:NPK fertilizer is primarily composed of three main elements: Nitrogen (N), Phosphorus (P), and Potassium (K), each of these being essential in plant nutrition. Nitrogen helps plants grow quicklyasPhosphorus supports the formation of oils, sugars, and starches. Potassium, being the third essential nutrient plants demand, assists in photosynthesis, fruit quality, the building of protein, and the reduction of disease.

Organic fertilizer:refers to a soil amendment derived from natural sources that guaranties, at least, the minimum percentages of nitrogen, phosphate and potash.

Inorganic fertilizer:is a fertilizer mined from mineral deposits or manufactured from synthetic compounds

Crops:the top layer of the earth in which plants, trees, etc grow.

REFERENCE

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