2020 JAMB AGRICULTURAL SCIENCE PAST QUESTIONS AND ANSWERS

Government plays a crucial role in agricultural development by supporting farmers and agricultural infrastructure. Providing labor is not a typical government role in agricultural production. Governments focus on policy, funding, and creating supportive environments for agricultural growth.

Agricultural extension programmes are designed to transfer agricultural knowledge and technologies to farmers. A successful programme must be adaptable, involve local farmers, and be based on research. An extension programme that relies only on highly trained specialists without farmer involvement is likely to fail.

When selecting livestock, farmers typically consider productive characteristics like body weight, mortality rate, and feed efficiency. Egg production is a specific trait for poultry and not a general livestock selection criterion. Therefore, egg production is not a standard quality for selecting livestock across different animal types.

In agricultural economics, investments with long-term benefits are classified as capital. Capital represents durable assets that contribute to production over extended periods. These are typically fixed assets like land, machinery, and long-term crop investments that provide ongoing economic value.

Consumer sovereignty in agriculture means that consumer preferences primarily drive production decisions. Consumers indicate what they want through their purchasing power, which influences farmers’ choices about what crops or products to produce. This economic principle ensures that production aligns with market demand.

Agricultural loans are typically used to support farming operations, including purchasing inputs, machinery, and covering operational costs. Marketing crops is a normal part of agricultural business and would be a legitimate use of agricultural loans. Therefore, marketing crops is not an exception to loan usage.

Agricultural extension agents play a critical role in knowledge transfer and technology dissemination in agriculture. Their primary responsibility is educating farmers about improved agricultural techniques, inputs, and modern farming practices. This helps farmers adopt more efficient and productive agricultural methods.

Ndama, Sokoto Gudali, and White Fulani are recognized cattle breeds found in Nigeria and West Africa. Sokoto Red is not a standard recognized cattle breed name. This question tests knowledge of Nigerian cattle breed classifications and variations.

Fish pond management requires careful attention to prevent disease outbreaks. Poor management practices can lead to stress, overcrowding, and unhygienic conditions that increase disease risk. Mixed stocking, if not managed carefully, can introduce pathogens and disrupt the pond ecosystem.

Animals approaching parturition (giving birth) exhibit several physiological changes. Typical signs include swollen and soft vulva, relaxed cervix, and full mammary glands. A drop in milk production is not a standard pre-parturition sign and would typically occur after giving birth.

The oestrus cycle is a critical reproductive period for female goats. Understanding the precise duration is essential for breeding management. In goats, the typical oestrus cycle ranges between 18 to 21 days, which is crucial for successful reproductive planning and artificial insemination.

Daily poultry management involves consistent care and monitoring to ensure bird health and productivity. Routine tasks include collecting eggs, providing water and feed, and ensuring proper health care. Debeaking is typically a periodic management practice rather than a daily routine, making it the exception in this list.

Castration in poultry involves removing the reproductive capabilities of a male bird. When a cockerel (male chicken) is castrated, it becomes a capon. Capons are known for their larger size, improved meat quality, and different behavioral characteristics compared to intact roosters.

Pigs are known for several valuable characteristics in agriculture. They are prolific, efficient feed converters, and a significant source of meat. Pigs do not serve as a source of land, which makes this option incorrect. Pigs are livestock that occupy land, not create or provide it.

Rinderpest is a severe viral disease affecting cattle. Vaccination is the most effective method of control and prevention. While sanitation and eradication of infected stock are important, vaccination provides the most comprehensive and proactive approach to disease management in cattle populations.

Drip irrigation is an efficient water management technique in agriculture. It allows precise fertilizer application, reduces salt concentration in root zones, and operates at lower pressures. Poor water distribution on steep slopes is a limitation of drip irrigation systems, making this the key disadvantage.

Windmills are traditional renewable energy sources in agricultural settings. Their primary function is pumping water from wells, providing a sustainable solution for water extraction in rural and agricultural areas. This makes pumping well water the most accurate application of windmill technology in agriculture.

In agricultural land preparation, different machinery serves specific purposes. The plough is specifically designed for breaking and turning soil, creating optimal conditions for seedbed preparation. It effectively breaks up soil structure, aerates the ground, and prepares it for planting.

Farm mechanization brings numerous benefits but also has potential drawbacks. Exposing soil to climatic effects is a significant limitation, as it can lead to increased erosion, moisture loss, and soil structure disruption. Mechanization does not inherently reduce production costs or increase crop yields.

Physical soil properties typically include observable characteristics like color, moisture content, and porosity. pH is a chemical property of soil that measures its acidity or alkalinity, not a physical property. This makes pH the exception in the list of physical soil characteristics.

Soil is a complex mixture composed of several key components. Air, water, and organic matter are fundamental components of soil structure. Texture refers to the size and proportion of soil particles, not a component itself, making it the exception in this list of soil constituents.

Sulphur is a critical nutrient in plant biochemistry, playing a vital role in protein formation and hormone production. It is an essential component of amino acids and helps in chlorophyll formation. Other nutrients have different primary functions in plant metabolism.

Soil formation begins with rock weathering, where temperature variations play a crucial role. Temperature changes cause rocks to expand and contract, creating initial cracks and crevices. This thermal stress is more consistent and widespread compared to other weathering agents like ice, wind, or human intervention.

Soil pH is a critical factor in agricultural productivity. A pH range of 6.1 to 6.9 indicates a slightly acidic soil condition. This range is close to neutral (pH 7) and is generally favorable for most crop growth, representing a slightly acidic soil environment.

Leguminous crops are unique in their ability to fix atmospheric nitrogen through symbiotic relationships with bacteria in their root nodules. This makes them an excellent source of proteins for both livestock and soil nutrition. Their protein-rich nature distinguishes them from other pasture crops.

Pasture crops are typically grasses and legumes used for livestock grazing. Mucuna, centrosema, and stylosanthes are leguminous plants often used in pastures. Giant star grass is a typical pasture grass. Among these options, mucuna stands out as the least common pasture crop.

Stem borers are notorious pests in maize cultivation, causing significant damage by creating tunnels within the plant stem. These insect larvae bore into the stem, causing structural weakness that leads to hollowness and lodging (plants falling over). This makes stem borers the most likely cause of such damage.

Quartz is the most abundant mineral in the Earth’s crust and a primary component of many rock types. It is especially prevalent in crystalline rocks like granite and sedimentary rocks like sandstone. Its resilience and widespread occurrence make it a key mineral in geological formations.

A soil pH of 2 indicates an extremely acidic condition. This is far from the neutral pH of 7 and represents a highly acidic environment that would be detrimental to most plant growth. Such extreme acidity can severely limit nutrient availability and plant survival.

Leaching is a significant issue in high rainfall areas, where excessive water movement through the soil profile removes essential nutrients. This process can rapidly deplete soil fertility, even in initially fertile soils. The continuous washing away of nutrients explains the poor crop yields in such environments.

Crop rotation is an essential agricultural practice that helps maintain soil health. It typically improves soil structure, reduces pest concentration, and maintains fertility. However, crop rotation does not predispose soil to leaching. In fact, it can help prevent leaching by improving soil structure and nutrient retention.

Igneous rocks are formed through the cooling and solidification of magma or lava. Granite is a classic example of an igneous rock, formed from the slow cooling of magma deep within the Earth’s crust. Gneiss is a metamorphic rock, while limestone and sandstone are sedimentary rocks.

Biotic factors are living components that affect agricultural production. Predators are living organisms that can impact crop and livestock production through direct interactions or ecological relationships. Unlike abiotic factors like rainfall or wind, predators represent a living, dynamic influence on agricultural systems.

Macro-nutrients are essential elements required by plants in larger quantities for growth and development. Phosphorus is a primary macro-nutrient crucial for plant energy transfer, root development, and overall plant metabolism. Zinc, iron, and manganese are micronutrients needed in smaller quantities.

Marketing boards are government institutions designed to support agricultural production and marketing. They help stabilize crop prices, provide market access, and support farmers by creating structured marketing channels for agricultural produce. This approach has been a key strategy in Nigerian agricultural policy.

In farm machinery, the hitch is a crucial component that connects the plough to the tractor or draft animals. It enables the implement to be pulled and allows for adjustments in depth and angle of cultivation. The hitch is essential for the proper functioning and maneuverability of the plough.

Theobroma cacao, commonly known as cocoa, is a tropical crop native to the Americas but widely cultivated in West Africa. The diagram likely shows a characteristic feature of the cocoa plant, such as its fruit or leaf structure. Cocoa is a critical cash crop for many West African countries, including Nigeria.

Budding is a vegetative propagation technique where a bud from one plant is inserted into the bark of another plant. The tool in the diagram appears to be specifically designed for this precise grafting method, allowing for careful insertion and attachment of plant buds.

Secateurs, also known as pruning shears, are specialized hand tools used for precise cutting of branches, stems, and plant material. They are designed for clean, sharp cuts in gardening and agricultural settings, making them ideal for pruning, grafting, and other detailed plant management tasks.

In agricultural economics, diminishing returns occur when additional inputs yield progressively smaller increases in output. The curve typically shows that after a certain point (point III), further input becomes less economically beneficial. This represents the optimal point where the marginal cost begins to exceed the marginal return.