WAEC SSCE - Agricultural Science - 2017 (Essay)
Question 1 Report
(a) Discuss maize smut disease under the follow-ing headings:
(i) causal organism (ii) mode of trans-mission (iii) two symptoms (iv) two cultural control measures
(b) Enumerate four forest management oractices in West Africa
(c) (i) State four classes of farm animals based on their uses (ii) Give one exam-ple of each class stated in (c)(i)
(a) Maize smut disease
(i) Causal organism:
A fungus, Ustilago maydis (also known as Ustilago zeae).
(ii) Mode of transmission:
The disease is transmitted mainly by wind or air-borne spores which are deposited on maize leaves, ears, tassels or other parts of susceptible plants. Spores may also survive in infected crop residues and soil.
(iii) Symptoms:
- Large galls or swellings occur on the ears/cobs, leaves, stems and tassels.
- The galls later burst and release black, powdery masses of spores; affected plants may become stunted or dwarfish.
(iv) Cultural control measures:
- Use clean, certified disease-free seeds or resistant varieties.
- Uproot and burn infected plants or galls and practise crop rotation.
(b) Four forest management practices in West Africa
- Afforestation and reforestation.
- Natural or artificial regeneration of forest trees.
- Selective exploitation or controlled felling of mature trees.
- Taungya system.
(c)(i) Four classes of farm animals based on their uses and (ii) one example of each
| Class of farm animal based on use | Example |
|---|---|
| Animals reared for food | Goat |
| Animals reared for work or draught | Ox |
| Animals reared for protection | Dog |
| Pet or companion animals | Cat |
Answer Details
(a) Maize smut disease
(i) Causal organism:
A fungus, Ustilago maydis (also known as Ustilago zeae).
(ii) Mode of transmission:
The disease is transmitted mainly by wind or air-borne spores which are deposited on maize leaves, ears, tassels or other parts of susceptible plants. Spores may also survive in infected crop residues and soil.
(iii) Symptoms:
- Large galls or swellings occur on the ears/cobs, leaves, stems and tassels.
- The galls later burst and release black, powdery masses of spores; affected plants may become stunted or dwarfish.
(iv) Cultural control measures:
- Use clean, certified disease-free seeds or resistant varieties.
- Uproot and burn infected plants or galls and practise crop rotation.
(b) Four forest management practices in West Africa
- Afforestation and reforestation.
- Natural or artificial regeneration of forest trees.
- Selective exploitation or controlled felling of mature trees.
- Taungya system.
(c)(i) Four classes of farm animals based on their uses and (ii) one example of each
| Class of farm animal based on use | Example |
|---|---|
| Animals reared for food | Goat |
| Animals reared for work or draught | Ox |
| Animals reared for protection | Dog |
| Pet or companion animals | Cat |
Question 2 Report
(a) State five factors that should be considered in choosing an irrigation system in West Africa.
(b) Mention four problems associated with irrigation in West Africa
(c) A rectangle-shaped farmland has a length of 0.4 km and a breadth of 2,400 m, calculate the area of the farmland in hectares
(d) List one primary and three secondary tillage implements
(a) Five factors to consider in choosing an irrigation system in West Africa:
- The source and availability of water (rivers, dams, boreholes).
- The topography (slope and nature) of the land.
- The type of soil and its infiltration/drainage.
- The type of crop to be grown and its water requirement.
- The cost of installation and the capital available to the farmer.
(b) Four problems associated with irrigation in West Africa:
- High cost of installing and maintaining the system.
- Salinization/salt build-up and water-logging of the soil.
- Inadequate/irregular water supply and silting of channels.
- Spread of water-borne diseases such as bilharzia and pests/weeds.
(c) Area of the farmland in hectares:
Convert the length to metres: \(0.4\ \text{km} = 0.4 \times 1000 = 400\ \text{m}\).
\[ \text{Area} = \text{length} \times \text{breadth} = 400\ \text{m} \times 2400\ \text{m} = 960{,}000\ \text{m}^2 \]
Since \(1\ \text{hectare} = 10{,}000\ \text{m}^2\):
\[ \text{Area} = \frac{960{,}000}{10{,}000} = 96\ \text{hectares} \]
(d) Tillage implements:
- One primary tillage implement: Plough (disc or mould-board plough).
- Three secondary tillage implements: Harrow, ridger and cultivator.
Answer Details
(a) Five factors to consider in choosing an irrigation system in West Africa:
- The source and availability of water (rivers, dams, boreholes).
- The topography (slope and nature) of the land.
- The type of soil and its infiltration/drainage.
- The type of crop to be grown and its water requirement.
- The cost of installation and the capital available to the farmer.
(b) Four problems associated with irrigation in West Africa:
- High cost of installing and maintaining the system.
- Salinization/salt build-up and water-logging of the soil.
- Inadequate/irregular water supply and silting of channels.
- Spread of water-borne diseases such as bilharzia and pests/weeds.
(c) Area of the farmland in hectares:
Convert the length to metres: \(0.4\ \text{km} = 0.4 \times 1000 = 400\ \text{m}\).
\[ \text{Area} = \text{length} \times \text{breadth} = 400\ \text{m} \times 2400\ \text{m} = 960{,}000\ \text{m}^2 \]
Since \(1\ \text{hectare} = 10{,}000\ \text{m}^2\):
\[ \text{Area} = \frac{960{,}000}{10{,}000} = 96\ \text{hectares} \]
(d) Tillage implements:
- One primary tillage implement: Plough (disc or mould-board plough).
- Three secondary tillage implements: Harrow, ridger and cultivator.
Question 3 Report
Discuss anthrax disease under the following headings (i) causal organism (ii) mode of transmission (iii) two symptoms (iv) two prevention and control measures
(b) (i) List four sources of plant protein in live stock feeds (ii) Give three examples of forage legumes that could be found in rangelands in West Africa
(c) Mention five characteristics of labour as a factor of agricultural production.
(a) Anthrax disease:
- (i) Causal organism: A bacterium, Bacillus anthracis.
- (ii) Mode of transmission: By ingestion of feed, water or pasture contaminated with the spores; through contact with infected animals, their carcasses or products; and through wounds and biting insects.
- (iii) Two symptoms:
- Sudden death, often with high fever before death.
- Discharge of dark, tarry, unclotted blood from natural body openings (nose, mouth, anus) and swellings on the body.
- (iv) Two prevention and control measures:
- Vaccinate healthy animals regularly against anthrax.
- Burn or bury deeply (with quicklime) the carcasses of infected animals; never open them, and isolate/quarantine affected herds.
(b)(i) Four sources of plant protein in livestock feeds:
- Groundnut cake
- Soya bean meal
- Palm kernel cake
- Cottonseed cake (or brewer's dried grain)
(b)(ii) Three examples of forage legumes in West African rangelands:
- Centrosema (Centrosema pubescens)
- Stylosanthes (Stylosanthes gracilis)
- Pueraria (Pueraria phaseoloides)
(c) Five characteristics of labour as a factor of agricultural production:
- Labour is human effort (physical and mental) used in production.
- Labour cannot be separated from the labourer.
- Labour is perishable; time lost when a worker is idle cannot be recovered.
- Labour is mobile; it can move from one place or job to another.
- Labour has feelings and needs rewards (wages), rest and good treatment to work well; its supply and efficiency vary.
Answer Details
(a) Anthrax disease:
- (i) Causal organism: A bacterium, Bacillus anthracis.
- (ii) Mode of transmission: By ingestion of feed, water or pasture contaminated with the spores; through contact with infected animals, their carcasses or products; and through wounds and biting insects.
- (iii) Two symptoms:
- Sudden death, often with high fever before death.
- Discharge of dark, tarry, unclotted blood from natural body openings (nose, mouth, anus) and swellings on the body.
- (iv) Two prevention and control measures:
- Vaccinate healthy animals regularly against anthrax.
- Burn or bury deeply (with quicklime) the carcasses of infected animals; never open them, and isolate/quarantine affected herds.
(b)(i) Four sources of plant protein in livestock feeds:
- Groundnut cake
- Soya bean meal
- Palm kernel cake
- Cottonseed cake (or brewer's dried grain)
(b)(ii) Three examples of forage legumes in West African rangelands:
- Centrosema (Centrosema pubescens)
- Stylosanthes (Stylosanthes gracilis)
- Pueraria (Pueraria phaseoloides)
(c) Five characteristics of labour as a factor of agricultural production:
- Labour is human effort (physical and mental) used in production.
- Labour cannot be separated from the labourer.
- Labour is perishable; time lost when a worker is idle cannot be recovered.
- Labour is mobile; it can move from one place or job to another.
- Labour has feelings and needs rewards (wages), rest and good treatment to work well; its supply and efficiency vary.
Question 4 Report
(a) Explain briefly each of the following economic concepts (i) scarcity (ii) scale of preference
(b) Give four reasons why agricultural insurance is important
(c) State five fishery regulations in West Africa
(d) Give five reasons why beekeeping is important
(a) Economic concepts:
- (i) Scarcity: Scarcity means that the resources (land, labour, capital) available to satisfy people's wants are limited relative to the unlimited wants. Because resources are limited, choices must be made.
- (ii) Scale of preference: A scale of preference is a list of a person's wants arranged in order of their importance, with the most pressing want at the top, so that the most urgent needs are satisfied first with the limited resources.
(b) Four reasons why agricultural insurance is important:
- It pays compensation to the farmer for losses from fire, flood, drought, pests or disease.
- It gives the farmer confidence to invest and expand the farm.
- It makes it easier for the farmer to obtain loans, since the insured farm is used as security.
- It spreads/reduces the risk of farming and keeps the farmer in business after a disaster.
(c) Five fishery regulations in West Africa:
- Use of nets with the approved (large) mesh size to protect young fish.
- Ban on the use of poisons, chemicals and explosives in fishing.
- Closed seasons during which fishing is prohibited to allow fish to breed.
- Licensing/registration of fishermen and fishing boats.
- Prohibition of catching immature/undersized fish and fishing in restricted zones.
(d) Five reasons why beekeeping is important:
- It produces honey used as food and medicine.
- It produces beeswax used in industry (candles, cosmetics, polishes).
- Bees pollinate crops and so increase crop yield.
- It provides income and employment to farmers.
- It requires little land and capital to start.
Answer Details
(a) Economic concepts:
- (i) Scarcity: Scarcity means that the resources (land, labour, capital) available to satisfy people's wants are limited relative to the unlimited wants. Because resources are limited, choices must be made.
- (ii) Scale of preference: A scale of preference is a list of a person's wants arranged in order of their importance, with the most pressing want at the top, so that the most urgent needs are satisfied first with the limited resources.
(b) Four reasons why agricultural insurance is important:
- It pays compensation to the farmer for losses from fire, flood, drought, pests or disease.
- It gives the farmer confidence to invest and expand the farm.
- It makes it easier for the farmer to obtain loans, since the insured farm is used as security.
- It spreads/reduces the risk of farming and keeps the farmer in business after a disaster.
(c) Five fishery regulations in West Africa:
- Use of nets with the approved (large) mesh size to protect young fish.
- Ban on the use of poisons, chemicals and explosives in fishing.
- Closed seasons during which fishing is prohibited to allow fish to breed.
- Licensing/registration of fishermen and fishing boats.
- Prohibition of catching immature/undersized fish and fishing in restricted zones.
(d) Five reasons why beekeeping is important:
- It produces honey used as food and medicine.
- It produces beeswax used in industry (candles, cosmetics, polishes).
- Bees pollinate crops and so increase crop yield.
- It provides income and employment to farmers.
- It requires little land and capital to start.
Question 5 Report
(a) List five non-government agricultural organizations in West Africa.
(b) State four ways in which agriculture and industry are interrelated
(c) Give one function of each of the following parts of a disc plough
(i) disc (ii) beam (iii) furrow wheel (iv) disc scraper (v) hitch
(d) State four disadvantages of animal power
(a) Five non-government agricultural organizations in West Africa:
- West Africa Rice Development Agency (WARDA/AfricaRice)
- International Institute of Tropical Agriculture (IITA)
- Food and Agriculture Organization (FAO)
- Sasakawa Global 2000
- International Fund for Agricultural Development (IFAD)
(b) Four ways in which agriculture and industry are interrelated:
- Agriculture supplies raw materials (cotton, cocoa, oil palm, rubber) to industries for processing.
- Industry supplies farm inputs (fertilisers, machines, chemicals) to agriculture.
- Agriculture provides food for industrial workers.
- Both provide market for each other's products and provide employment and income.
(c) One function of each part of a disc plough:
| Part | Function |
|---|---|
| (i) Disc | Cuts, lifts and turns over the soil (does the actual ploughing). |
| (ii) Beam | The main frame to which other parts are attached; it carries and holds the plough together. |
| (iii) Furrow wheel | Runs in the furrow to give stability and balance and control the depth/width of ploughing. |
| (iv) Disc scraper | Removes/clears soil sticking to the disc so it can rotate and cut freely. |
| (v) Hitch | Connects the plough to the tractor for pulling. |
(d) Four disadvantages of animal power:
- Animals are slow and cover only a small area of land per day.
- They tire easily and cannot work for long hours.
- They need feeding, housing and veterinary care, which cost money and time.
- They can be affected by diseases and may die, and cannot be used on all types of land.
Answer Details
(a) Five non-government agricultural organizations in West Africa:
- West Africa Rice Development Agency (WARDA/AfricaRice)
- International Institute of Tropical Agriculture (IITA)
- Food and Agriculture Organization (FAO)
- Sasakawa Global 2000
- International Fund for Agricultural Development (IFAD)
(b) Four ways in which agriculture and industry are interrelated:
- Agriculture supplies raw materials (cotton, cocoa, oil palm, rubber) to industries for processing.
- Industry supplies farm inputs (fertilisers, machines, chemicals) to agriculture.
- Agriculture provides food for industrial workers.
- Both provide market for each other's products and provide employment and income.
(c) One function of each part of a disc plough:
| Part | Function |
|---|---|
| (i) Disc | Cuts, lifts and turns over the soil (does the actual ploughing). |
| (ii) Beam | The main frame to which other parts are attached; it carries and holds the plough together. |
| (iii) Furrow wheel | Runs in the furrow to give stability and balance and control the depth/width of ploughing. |
| (iv) Disc scraper | Removes/clears soil sticking to the disc so it can rotate and cut freely. |
| (v) Hitch | Connects the plough to the tractor for pulling. |
(d) Four disadvantages of animal power:
- Animals are slow and cover only a small area of land per day.
- They tire easily and cannot work for long hours.
- They need feeding, housing and veterinary care, which cost money and time.
- They can be affected by diseases and may die, and cannot be used on all types of land.
Question 6 Report
(a) Draw a well labelled diagram of the water cycle
(b) Mention two deficiency symptoms of phosphorus in crops
(c) Using the table below, classify the follow-ing insect-pests according to their modes of feeding (i) weevil (ii) locust (iii) scale insect (iv) armyworm (v) earworm (vi) cotton stainer (vii) green spidermites (viii) thrips (ix) capsids (x) yam beetle
(a) Water cycle
(b) Deficiency symptoms of phosphorus in crops
- Stunted growth and poorly developed roots.
- Leaves, especially older leaves, develop a purplish or reddish coloration, usually beginning from the tips.
- Flowering, seed formation and maturity may be delayed or reduced.
(c) Classification of insect pests according to mode of feeding
| Biting and chewing pests | Piercing and sucking pests | Boring pests |
|---|---|---|
| Locust Armyworm | Scale insect Cotton stainer Green spider mites Thrips Capsids | Weevil Earworm Yam beetle |
Answer Details
(a) Water cycle
(b) Deficiency symptoms of phosphorus in crops
- Stunted growth and poorly developed roots.
- Leaves, especially older leaves, develop a purplish or reddish coloration, usually beginning from the tips.
- Flowering, seed formation and maturity may be delayed or reduced.
(c) Classification of insect pests according to mode of feeding
| Biting and chewing pests | Piercing and sucking pests | Boring pests |
|---|---|---|
| Locust Armyworm | Scale insect Cotton stainer Green spider mites Thrips Capsids | Weevil Earworm Yam beetle |
