WAEC SSCE - Agricultural Science - 2021 (Essay)

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(a) Identification of specimens:

J= Leaf eating beetle

K = Aphid

L = Bean beetle

 M = Termites or Mole Cricket.

(b) Damage done to crops by specimens K and L are: Specimen K (Aphid) 

(i) It causes stunted growth 

(ii) It causes galls on leaves. 

(iii) It is a vector of diseases. Specimen L (Callosobruchus spp) 

(i) They bore holes into grains and eat them up. 

(ii) They reduce the quality of stored produce. 

(iii) They reduce grains to powder.

(c)

(i) Spray with insecticides. 

(ii) Hand pick them. 

(iii) Use resistant varieties. 

(iv) Early planting 

(v) Crop rotation.

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a) The roles played by the following factors in soil formation are:

(i) Time: Time is an essential factor in soil formation, as it allows for the gradual accumulation of organic matter, weathering of rocks, and the development of soil structure. Over time, soil also becomes more diverse in terms of its physical, chemical, and biological properties, leading to the formation of different soil types.

(ii) Rainfall: Rainfall is another critical factor in soil formation, as it influences soil structure, nutrient availability, and the transport of minerals and organic matter. In areas with high rainfall, leaching can occur, leading to the depletion of essential nutrients. In contrast, low rainfall can result in soil salinization and compaction.

(iii) Parent Material: Parent material refers to the underlying rock or sediment from which the soil is formed. Different types of parent material have varying mineral compositions, which affect the fertility and physical properties of the soil. For example, soils formed from limestone are generally alkaline, while those formed from granite tend to be more acidic.

b) Principles that should be followed in a good crop rotation plan include:

(i) Diversity: A good crop rotation plan should include a diverse range of crops to reduce the risk of disease and pest outbreaks and maintain soil fertility.

(ii) Timing: The timing of crop rotations is also crucial, as different crops have varying nutrient requirements and growth rates. A well-planned crop rotation should consider the optimal timing for planting, harvesting, and fallowing.

(iii) Soil health: A good crop rotation plan should aim to improve soil health by reducing erosion, maintaining soil structure, and increasing soil organic matter.

c) Forage crops are plants that are grown specifically for livestock feed. The uses of forage crops include:

(i) Providing nutrition: Forage crops are a source of high-quality feed for livestock, providing essential nutrients such as protein, fiber, and energy.

(ii) Improving soil health: Forage crops can improve soil health by adding organic matter, reducing soil erosion, and enhancing soil structure.

(iii) Cost-effective: Forage crops can be a cost-effective alternative to purchased feeds, reducing the overall cost of livestock production.

(iv) Sustainability: Forage crops are an essential component of sustainable agriculture, as they can help to reduce the environmental impact of livestock production by reducing the need for synthetic fertilizers and other inputs.

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(a) ldentification of specimens:

D = Measuring tape, E = 

Budding knife

F = Plier

G = Measuring chain or Gunter's chain

H = Spanner

I = Screwdriver

(b) Functions of each of the specimens are:

D is used in taking measurements of length, breadth, and height.

E is used mainly in budding (by vegetative propagation) in citrus, cocoa, rubber etc.

F is used:

(i) For gripping firmly and twisting wires

(ii) for holding bolts and nuts.

G is used in taking a short or detailed measurements of length and breadth.

H is used in loosening or tightening of nuts/ bolts on farm machines.

I is used for turning or screwing nails or Screws into or out of wooden or metal surfaces and to detect the presence of electric current.

(c) Methods of maintaining each of the specimens are 

D = Clean after use

E = Sharpen cutting edge regularly

 F = Oil or grease after use

G = Store in a cool and dry place

H = Oil or grease metal parts before storage

 I = use according to specification or for the intended purpose.

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a. The roles of the government of West African countries in agricultural development are as follows: (i) Agricultural finance: The government plays a crucial role in providing financial support to the agricultural sector. This includes offering loans, grants, and subsidies to farmers, especially small-scale farmers who may have limited access to capital. The government may also establish agricultural development banks or funds to provide financial assistance and promote investment in agriculture. (ii) Agricultural education: The government recognizes the importance of educating farmers and individuals involved in the agricultural sector. They establish agricultural colleges, universities, and training centers to provide formal education and training in agricultural practices, techniques, and technologies. These institutions offer courses on crop cultivation, animal husbandry, agricultural economics, and other relevant subjects. (iii) Agricultural extension services: Governments set up agricultural extension services to bridge the gap between agricultural research and farmers. These services aim to disseminate up-to-date information, best practices, and new technologies to farmers. Extension workers, often employed by the government, visit rural areas to provide guidance, advice, and training to farmers, helping them improve their farming methods and productivity. (iv) Agricultural policies and programs: Governments formulate agricultural policies and programs to provide a framework for sustainable agricultural development. These policies encompass areas such as land reform, crop diversification, irrigation, rural infrastructure development, market access, and trade regulations. The government's role is to design and implement these policies, ensuring they align with the needs and priorities of the agricultural sector and contribute to its growth and productivity. b. Structural differences between disc plough and disc harrow: Disc Plough: - The disc plough is a tillage implement used for primary or deep ploughing. - It has large, concave metal discs (usually two or more) mounted on a frame. - The discs are spaced apart and have a cutting edge that penetrates the soil and turns it over. - The plough is pulled by a tractor, and the discs create furrows in the soil as they rotate. - It is primarily used for breaking up hard or compacted soil, burying crop residues, and preparing the land for planting. Disc Harrow: - The disc harrow is a secondary tillage implement used after ploughing to prepare the soil for planting. - It consists of a series of smaller, individual concave metal discs mounted on a common shaft. - The discs are closely spaced and have a serrated edge that cuts through the soil and breaks up clumps. - The harrow is also pulled by a tractor, and the discs rotate as they move along the ground. - It is primarily used for leveling the soil, breaking up clods, and incorporating fertilizers or amendments into the topsoil. c. Effects of frequent use of disc plough on the soil: Frequent use of a disc plough can have both positive and negative effects on the soil. Here are some simple explanations: Positive effects: 1. Soil loosening: The disc plough breaks up compacted soil and loosens it, which improves aeration and water infiltration. This allows plant roots to penetrate the soil more easily and access nutrients. Negative effects: 1. Soil erosion: Intensive or improper use of the disc plough can lead to soil erosion. When the soil is turned over, it becomes more vulnerable to wind and water erosion, potentially causing valuable topsoil to be washed or blown away. 2. Organic matter loss: Disc ploughing can accelerate the decomposition of organic matter present in the topsoil. This may lead to a decrease in soil fertility and a reduction in the soil's ability to retain moisture. 3. Soil compaction: If the disc plough is used when the soil is too wet or not properly managed, it can cause compaction. The weight and repeated passes of

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a. (i) Some of the main agricultural extension methods that could be used to create awareness of diseases among poultry farmers are:

• Workshops and seminars: Organizing workshops and seminars where poultry farmers can learn about the disease and how to prevent it.
• Field days: Organizing field days where farmers can observe how to identify and treat the disease.
• Printed materials: Distributing printed materials such as flyers, brochures, and posters that provide information about the disease and how to prevent it.
• Audiovisual materials: Creating audiovisual materials such as videos and slideshows that can be shown to farmers to educate them about the disease.

(ii) The most appropriate extension method to create awareness of the disease among poultry farmers would be workshops and seminars. This is because workshops and seminars provide a platform where farmers can interact with experts and other farmers to learn about the disease and how to prevent it. This method allows for interactive learning, which is more effective in creating awareness and ensuring that farmers understand the disease and its prevention.

(iii) The reason for choosing the mass method is that it allows for the dissemination of information to a large number of people at once. This is important when dealing with a disease outbreak, as it allows for quick dissemination of information to farmers, which can help prevent the spread of the disease.

(iv) Some problems likely to be encountered by the use of the mass method include the possibility of information overload, where farmers may not be able to absorb all the information provided to them. Additionally, the method may not be effective in reaching all farmers, especially those in remote areas with limited access to information and communication technologies.

b. Some problems faced by farm managers include:

• Managing production costs: Farm managers need to manage production costs to ensure profitability. This involves managing input costs such as feed, labor, and equipment, and ensuring that they do not exceed the revenue generated from sales.
• Marketing: Farm managers need to ensure that their products are marketed effectively to generate sales. This involves identifying market opportunities, developing marketing strategies, and building relationships with buyers.
• Managing risks: Farm managers need to manage risks such as disease outbreaks, weather events, and market fluctuations. This involves implementing risk management strategies such as insurance, diversification, and contingency planning.
• Managing labor: Farm managers need to manage labor effectively to ensure that the farm operates efficiently. This involves recruiting, training, and retaining skilled labor, as well as managing labor costs.

c. Some common breeds of goats found in West Africa include the West African Dwarf, the Sahelian, and the Red Sokoto. The West African Dwarf is a small, hardy breed that is well adapted to the humid conditions of West Africa. The Sahelian is a larger breed that is well adapted to the arid conditions of the Sahel region. The Red Sokoto is a meat breed that is well adapted to the semi-arid conditions of northern Nigeria. These breeds are well adapted to the environmental conditions and farming systems in West Africa and are commonly kept by smallholder farmers for meat and milk production.

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a. Reasons why farm operations are important: (i) Pruning of cocoa trees: 1. Enhanced tree health: Pruning helps remove dead, diseased, or damaged branches, promoting overall tree health. It allows better air circulation and sunlight penetration, reducing the risk of fungal infections and pests. 2. Increased yield: Pruning encourages new growth and stimulates the development of fruit-bearing branches, leading to higher cocoa bean production. 3. Easy harvest: Properly pruned cocoa trees have a well-defined canopy, making it easier for farmers to access and harvest the cocoa pods. 4. Disease control: Pruning facilitates disease control measures as it allows farmers to spot and remove infected branches promptly, preventing the spread of diseases within the cocoa plantation. (ii) Parboiling of paddy rice: 1. Improved grain quality: Parboiling involves partially boiling the rice in its husk before milling. This process enhances the nutritional value and taste of the rice while retaining essential vitamins and minerals. 2. Reduced processing time: Parboiling softens the rice kernels, making it easier to remove the husk during milling. This reduces the time and effort required for processing, resulting in increased efficiency. 3. Enhanced storage and shelf life: Parboiling reduces the moisture content of rice and improves its resistance to pests and insects. It also prevents the development of mold, extending the shelf life of the rice. 4. Enhanced cooking properties: Parboiled rice retains its shape, texture, and flavor better during cooking, resulting in fluffy, separate grains. It is less prone to overcooking or becoming sticky, making it more desirable for consumers. b. Ways of eradicating guinea grass in a farmland: 1. Manual removal: Physically uprooting or cutting the guinea grass is an effective way to control its growth. Ensure that the roots are completely removed to prevent regrowth. 2. Herbicides: Applying herbicides specifically designed to target grassy weeds like guinea grass can be an efficient method. Follow the instructions and safety guidelines provided by the herbicide manufacturer. 3. Mulching: Applying a thick layer of organic mulch around desired plants can suppress the growth of guinea grass by blocking sunlight and impeding its germination. 4. Regular mowing: Keeping the grass at a low height through regular mowing can weaken and suppress the guinea grass. This method should be combined with other control measures for better effectiveness. 5. Prevention: Maintaining good farm hygiene by regularly removing weeds, especially before they produce seeds, can prevent the spread and establishment of guinea grass. c. Uses of ornamental plants: 1. Aesthetics: Ornamental plants are primarily grown for their beauty and visual appeal. They enhance the overall aesthetics of gardens, parks, and landscapes, providing a pleasant and inviting environment. 2. Stress reduction: Being surrounded by greenery and nature has been found to reduce stress and improve mental well-being. Ornamental plants contribute to creating a calming and relaxing atmosphere. 3. Environmental benefits: Ornamental plants play a role in improving air quality by absorbing carbon dioxide and releasing oxygen during photosynthesis. They also help mitigate noise pollution and provide habitat for wildlife. 4. Educational purposes: Ornamental plants provide educational opportunities, especially for children, to learn about plant biology, gardening, and environmental conservation. 5. Cultural significance: Many ornamental plants hold cultural or symbolic value in various societies and traditions. They can be used in religious ceremonies, festivals, and decorations during special occasions. 6. Wildlife attraction: Certain ornamental plants attract birds, butterflies, and other pollinators, contributing to biodiversity and ecosystem health. 7. Economic value: Ornamental plants form the basis of the horticulture industry, including nurseries, florists, and landscaping businesses. They contribute to

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(a) specimens

N = Fresh skin of poultry fowl

O = Fresh skin /hide of ruminant

P = Kidney (whole) of goat

Q = Horn

(b) Specimen N is derived from poultry birds such as domestic fowl, turkey, goose, duck etc while specimen O is derived from ruminant animals like cattle, sheep, and goat.

(c) Two functions of specimens N, O, and P that are common to farm animals are

N

(i) It protects the internal organs. 

(ii) It prevents the entrance of disease organisms.

O

(i) It aids excretion. 

(ii) It aids the production of milk in females.

P 

(i) It aids excretion

 (ii) It helps in the osmo- regulation of the body.

(d)

(i) It can be used to make shoe, belt, cap, baskets, drum, etc.

 (ii) Tick, Liver fluke, Tapeworm, or Ascaris.

(e) The condition in which an animal does not possess specimen Q is when the animal is a non-ruminant.

(f) Importance of specimen Q to farm animals are 

(i) It is used to fight or defend themselves. 

(ii) It gives them shape 

(iii) It aids swimming, e.g. kuri cattle.

Importance of specimen Q to man are 

(i) It serves as raw material in knife handles, belt heads etc. 

(ii) It is used for decorative purposes. 

(iii) It is used to make livestock feeds

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a.

i. Selective exploitation in forest management refers to the practice of harvesting only a portion of the mature trees in a forest, while leaving the rest to continue growing and contributing to the ecosystem. This approach aims to maintain the overall health and productivity of the forest while also providing economic benefits through timber harvesting.

ii. Some advantages of selective exploitation of forest trees include:

• Sustainable management: Selective exploitation helps to ensure that forests are managed in a sustainable manner, as only a portion of the mature trees are harvested, leaving the rest to continue growing and contributing to the ecosystem.
• Biodiversity conservation: Selective exploitation can help to conserve biodiversity by leaving habitat for wildlife and preserving a variety of tree species and other plants in the forest.
• Economic benefits: Selective exploitation provides economic benefits through timber harvesting, while also maintaining the overall health and productivity of the forest.
• Carbon sequestration: Forests play an important role in carbon sequestration, and selective exploitation can help to maintain this function by preserving mature trees that continue to store carbon.

b. Field pests are insects and other organisms that attack crops while they are growing in the field. Examples of field pests include aphids, caterpillars, and grasshoppers. Storage pests, on the other hand, are insects and other organisms that attack crops after they have been harvested and stored. Examples of storage pests include weevils, moths, and beetles.

c.

i. Examples of storage insect pests of crops include the maize weevil, rice weevil, and bean beetle. These insects can infest stored crops such as grains, beans, and nuts, causing damage and reducing the quality of the harvested crops.

ii. Examples of field insect pests of crops include aphids, which can infest and damage a variety of crops including fruits, vegetables, and grains; armyworms, which can cause extensive damage to corn and other crops; and Colorado potato beetles, which can damage potato plants.

d. Ways of conserving water in the soil include:

• Mulching: Mulching involves covering the soil with a layer of organic material such as leaves, straw, or wood chips. This helps to reduce water evaporation from the soil, keeping it moist for longer periods of time.
• Irrigation management: Proper irrigation management can help to conserve water in the soil by reducing water loss through runoff or deep percolation. This can be achieved through techniques such as drip irrigation, which delivers water directly to the roots of plants, or by using water-efficient irrigation systems.
• Soil management: Managing the soil can also help to conserve water. Techniques such as adding organic matter to the soil can improve its water-holding capacity, while reducing tillage can help to minimize soil disturbance and water loss through evaporation.
• Crop selection: Choosing crops that are adapted to the local climate and soil conditions can help to conserve water, as these crops will require less irrigation and can better tolerate dry conditions.

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(a) ldentification of specimens:

A = NPK fertilizer 

B = Ammonium Sulphate

C = Lime 

(b) The main nutrient(s) released by each specimen are 

Specimen A = Nitrogen, phosphorus, and potassium; 

Specimen B = Nitrogen

Specimen C = Calcium.

(c) Ammonium Nitrate and urea can be used as substitutes for specimen B.

(d) It can increase the acidity of the soil

(e)

(i) Role of specimen C in crop production are: 

(1) It helps to reduce soil acidity. 

(2) It Increases the activities of soil living organisms. 

(3) It improves the soil structure. 

(4) It increases water percolation in soils. 

(ii) Role of Specimen C in fish production are: 

(1) It serves as an additional source of calcium for bone development in fish. 

(2) It reduces turbidity in the fish ponds through flocculation.

(f)

(i)Quicklime 

(ii) Slaked lime 

(iii) Basic Slag. 

(iv) Dolomite 

(v) Calcium carbonate.