WAEC SSCE - Agricultural Science - 2022

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

The group of crops that will thrive in areas with high rainfall is Guinea corn, cowpea, and maize. This is because these crops are well adapted to the tropical climate, and can withstand the high humidity and rainfall associated with such areas. Additionally, they require high moisture content for good germination and growth. Cotton, cowpea, and groundnut, on the other hand, are crops that thrive better in semi-arid areas, where there is less rainfall. Millet, maize, and cotton can also be grown in areas with low to moderate rainfall, but may not do well in areas with high rainfall due to increased risk of fungal diseases and waterlogging. Cocoa, oil palm, and rubber are tree crops that are grown in areas with high rainfall, but they require specific conditions such as well-drained soils and specific climatic conditions to thrive.

Maelezo ya Majibu

Based on the diagram provided, the aim of the experiment is to determine the soil texture. Soil texture refers to the relative proportion of different particle sizes in soil, such as sand, silt, and clay. The tool shown in the diagram is a soil texture analysis apparatus, commonly known as a hydrometer, which measures the rate of settling of suspended soil particles in water. The time taken for different-sized particles to settle can be used to calculate the proportions of sand, silt, and clay in the soil sample, which in turn determines its texture.

Maelezo ya Majibu

Maelezo ya Majibu

The tool in the diagram is a sieve, and the part labelled II is the mesh size of the sieve. The mesh size determines the diameter of the soil particle that can pass through it. So, the diameter of the soil particle that would be retained in the part labelled II is the size range of the mesh, which is 0.02 - 0.2 mm. Therefore, the answer is the second option: 0.02 - 0.2 mm.

Maelezo ya Majibu

To calculate the total amount of eggs sold, we need to add up the number of eggs sold on each day. According to the table, on the 4th of June, 96 eggs were sold, on the 5th of June, 108 eggs were sold, and on the 6th of June, 48 eggs were sold. Therefore, the total amount of eggs sold is 96 + 108 + 48 = 252. So, the correct option is 252.

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

Water can be conserved in the soil through various management practices that aim to reduce evaporation and runoff, and increase infiltration and water holding capacity. Mulching, strip cropping, and cover cropping are among the best ways to conserve water in the soil. Mulching involves covering the soil with organic or inorganic materials such as leaves, straw, or plastic, which reduces water loss due to evaporation and helps retain moisture in the soil. Strip cropping involves alternating strips of crops or cover crops with fallow land or other crops, which reduces runoff and erosion, and improves water infiltration and soil structure. Cover cropping involves planting a cover crop that can hold water in the soil, reduce evaporation, and improve soil health. By implementing these practices, water can be conserved in the soil, which is important for sustainable agriculture and the efficient use of water resources.

Maelezo ya Majibu

Decomposition of soil organic matter is mainly caused by bacteria. Bacteria are single-celled microorganisms that are ubiquitous in soil and are responsible for breaking down complex organic matter into simpler forms. They play a vital role in the cycling of nutrients in soil ecosystems. When organic matter is added to soil, bacteria break down the complex molecules into smaller molecules such as sugars, amino acids, and fatty acids, which can then be used by plants for growth and development. Bacteria also help to release nutrients from organic matter into the soil, making them available for plant uptake. Without bacteria, organic matter would accumulate in the soil and become unavailable for plant growth.

Maelezo ya Majibu

Maelezo ya Majibu

Monocotyledonous crops are plants that have one cotyledon (seed leaf) in their embryo. Some common examples of monocotyledonous crops include rice, maize, wheat, barley, sorghum, sugarcane, bamboo, and grasses like Bermuda and Bluegrass. Therefore, the correct option from the given choices is "oil palm, rice, and plantain".

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

Weed control is essential for the healthy growth of trees in plantations. One of the most common ways to control weeds in tree crop plantations is by slashing. Slashing involves using a machete or a special tool to cut down the weeds at their base. This method is effective because it cuts off the weed's supply of nutrients and light, which eventually leads to their death. Slashing is relatively inexpensive and does not require the use of harmful chemicals that could be dangerous to the environment or human health. It is also less labor-intensive compared to hand-pulling weeds, especially in large plantations.

Maelezo ya Majibu

Maelezo ya Majibu

Ranging poles used in farm surveying typically have red and white bands. This is because the high contrast between the red and white bands makes the poles highly visible even from a distance. The poles are used to mark the boundaries and reference points in the field, and their visibility is important for accurate measurements and mapping. The use of red and white bands is a standard practice in surveying and is recognized internationally.

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

Swampy lands are most suitable for growing rice. This is because rice thrives in wetland environments where there is abundant water supply. Swampy lands usually have a high water table and can retain moisture for a long time, making them ideal for the cultivation of rice. Additionally, rice is a semi-aquatic crop that can tolerate flooding, making it well-suited for growing in areas with fluctuating water levels. Therefore, rice is the most suitable crop to grow in swampy lands.

Maelezo ya Majibu

The removal of needle teeth is important in the management of piglets. Piglets are born with needle-like teeth that can cause injuries to the sow's udder and to other piglets during nursing. These teeth can also cause damage to the piglets' mouth, making it difficult for them to feed and thrive. The removal of needle teeth is therefore important to promote the health and well-being of the piglets, as well as to prevent injuries to the sow and other piglets in the litter. It is usually done within the first few days after birth, using specialized clippers or a hot iron cautery.

Maelezo ya Majibu

Potassium is an essential nutrient for the growth and development of cereal crops. When there is a deficiency of potassium, it can be indicated by browning of leaves from the tips and margins. The leaves may also become weak and susceptible to disease and pests. This is because potassium helps in the regulation of plant water balance and strengthening of cell walls. Therefore, a lack of potassium can lead to water stress and weaker cell walls, causing the leaves to turn brown and die. Yellowing of younger leaves is not usually associated with potassium deficiency but rather with other nutrient deficiencies such as nitrogen. Purpling of leaves can be a sign of phosphorus deficiency. White and irregular spots on leaves can be caused by fungal or bacterial infections.

Maelezo ya Majibu

Soil-borne diseases are caused by pathogenic microorganisms that are present in the soil. These diseases can infect seedlings in the nursery and cause significant damage to crops. To control soil-borne diseases in the nursery, it is important to take preventive measures. One of the effective ways to control soil-borne diseases in the nursery is through heat treatment. Heat treatment involves exposing the soil to high temperatures to kill off the pathogenic microorganisms. Another method is to use sterilized soil or a soil-less growing medium, which can help prevent the buildup of disease-causing organisms. Providing proper drainage and ventilation in the nursery can also help to prevent the buildup of moisture, which can create conditions that are conducive to the growth of pathogens. Finally, good hygiene practices such as regularly cleaning tools and equipment used in the nursery can help prevent the spread of soil-borne diseases.

Maelezo ya Majibu

Maelezo ya Majibu

To calculate the income from unsold eggs, we need to first find out the total number of unsold eggs. To do that, we add up the total eggs collected and subtract the total eggs sold for each day: Total eggs collected = 176 + 199 + 177 = 552 Total eggs sold = 96 + 108 + 48 = 252 Total unsold eggs = 552 - 252 = 300 Next, we need to find out how many crates the unsold eggs make by dividing the total number of unsold eggs by 30: Number of crates of unsold eggs = 300 ÷ 30 = 10 Finally, we can calculate the income from the unsold eggs by multiplying the number of crates by the price per crate: Income from unsold eggs = 10 x ₦5.00 = ₦50.00 Therefore, the answer is option (C) ₦50.00.

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

Castration is the surgical removal or destruction of the testicles of male farm animals, such as bulls, rams, and boars. The main reason for castrating farm animals is to make them sterile, that is, unable to reproduce. This is often done to control breeding, reduce aggression, and improve meat quality. Castrated animals also tend to grow faster and produce leaner meat, which is why it can indirectly lead to increased meat production. The removal of the testicles also causes a reduction in testosterone levels, which can lead to a decrease in male odour and potentially result in a loss of weight.

Maelezo ya Majibu

The table illustrates a production record for Goodness Farms in the year 1970. This is because it records the number of hens on the farm and the total eggs collected and sold over a period of three days. A production record is used to keep track of the amount of output or yield produced on a farm within a specific period. Therefore, this table is an example of a production record because it records the number of eggs produced and sold within a specific period.

Maelezo ya Majibu

Physical weathering and chemical weathering are two different processes that break down rocks into smaller particles. Physical weathering breaks down rocks into smaller pieces without altering the chemical composition of the rock, while chemical weathering changes the composition of rocks by altering the minerals or chemicals that make up the rock. Therefore, the correct answer is: "the mineral composition of rock is changed in chemical weathering."

Maelezo ya Majibu

Lactation normally occurs after gestation. It is a natural physiological process that occurs in most female mammals after giving birth. During gestation, the mammary glands prepare for milk production, and once the offspring is born, the hormone prolactin is released, which stimulates milk production. This process continues as long as the offspring continues to nurse. Therefore, lactation is an important aspect of post-natal care and is essential for the survival and growth of the offspring.

Maelezo ya Majibu

Goats will browse more on plants in a pasture compared to other farm animals. Browsing refers to the act of feeding on bushes and trees above the ground level. Goats have a natural inclination to browse as they prefer to eat leaves, twigs, and small branches. In contrast, cattle, pigs, and sheep are mainly grazers and prefer to eat grass that is close to the ground. While all four animals will eat a variety of plants, goats are more likely to browse on a wider range of plants, making them useful for controlling weeds and managing vegetation in pastures.

Maelezo ya Majibu

Maelezo ya Majibu

The correct order of arrangement of ration for piglets from day old is: creep > weaners > growers > finisher. This is because piglets require different levels of nutrients and energy at different stages of their growth. The creep feed is provided to piglets during the nursing period, usually starting at around 3 weeks of age. After weaning, the piglets are fed with weaner feed, which has a higher protein content to aid in their growth and development. As they continue to grow, they are then given growers feed, which contains the necessary nutrients for optimal growth. Finally, as the pigs reach finishing weight, they are provided with finisher feed which is high in energy and designed to add more fat to the pig's body.

Maelezo ya Majibu

The disease of citrus described above is gummosis. This is because one of the symptoms mentioned is the exudation of gum, which is a characteristic symptom of gummosis. Yellowing of leaves, raised brown spots on the leaves, and drying up of leaves are not typically associated with gummosis, but can be symptoms of other citrus diseases. Blight and tristeza are also citrus diseases, but they do not typically cause gum exudation as a symptom.

Maelezo ya Majibu

The correct match between a crop and a disease that affects it is: - Maize - smut Smut is a fungal disease that affects maize plants. It causes the formation of large, black, powdery masses on the ears, tassels, leaves, and stems of the plant. The masses contain millions of fungal spores that can be spread by wind, rain, and insects to other plants. Smut can reduce the yield and quality of maize crops, and infected plants should be removed and destroyed to prevent the disease from spreading. The other options are incorrect matches between crops and diseases: - Sorghum - scab (scab is a disease that affects wheat and barley) - Rice- black arm (black arm is a disease that affects cotton) - Yam- blast (blast is a disease that affects rice)

Maelezo ya Majibu

Maelezo ya Majibu

Maelezo ya Majibu

The gross profit of a farm business is the total revenue generated by the farm from its sales minus the total cost of production. It represents the amount of money left over after deducting all direct costs associated with producing and selling the goods, before taking into account any overhead or indirect costs. Therefore, the correct answer is "total sales less cost of production."

Maelezo ya Majibu

(a)Farm animals Possessing specimen A(Horn): Sheep, Goat, Cattle, etc.

(b) Methods of removing specimen A are
i. Use of electrical dehorner
ii. Use of gouge
iii. Use saws
iv. Use hot iron/Fire
v.Use chemicals etc.

(c) Methods of rearing specimen B (layers/chicken) are: deep litter, battery cage, fold, free range or open-range

(d) Undesirable qualities for culling specimen B/ Reasons for culling specimen L are: pale and scaly comb, pale and scaly wattles, sunken, dull and split pupils, yellow beak, rounded and lustreless tail, feather broken after laying for some time, hard abdomen with little or no capacity narrow distance between the breast bone and pelvic bones to 2-3 fingers., It has overweight due to excess fat, very light, hard and dry skin, small dry vent, yellow shank, broodiness, cannibalism, low egg production or ceasation of laying.

Maelezo ya Majibu

(a) - Monocropping: This is a cropping system in which only one crop is grown on a piece of land at a time. It involves planting the same crop in the same field year after year. This system is efficient for large-scale farming, easy to manage, and allows for the use of large machinery.

- Mixed cropping: This is a cropping system in which two or more crops are grown on the same piece of land at the same time. The crops grown are usually complementary in nature, meaning they do not compete for the same nutrients and other resources. This system is beneficial because it reduces the risk of crop failure due to pests, diseases or adverse weather conditions.

- Mixed farming: This is an agricultural system that combines crop farming with animal husbandry. The farmer grows crops and raises animals on the same piece of land. The crops provide feed for the animals, while the animals provide manure for the crops. This system is beneficial because it allows for the efficient use of resources and provides a diversified source of income for the farmer.

- Crop rotation: This is a cropping system in which different crops are grown on the same piece of land in a specific sequence over a period of time. This system helps to maintain soil fertility, reduce soil erosion, and control pests and diseases. It involves rotating crops with different nutrient requirements and growth patterns, to ensure that the soil remains healthy and productive.

(b) (i) The orange plants are deficient in phosphorus.

(ii) Four inorganic fertilizers that could correct the nutrient deficiency in the orange plants are: triple superphosphate, single superphosphate, diammonium phosphate, and ammonium phosphate. These fertilizers are rich in phosphorus, which is essential for plant growth and development.

(c) Five materials that could be used to attract bees to a new beehive are: sugar syrup, pollen, honey, beeswax, and pheromones. Sugar syrup is used to provide a source of energy for the bees, pollen and honey are used to attract foragers, beeswax is used to provide a familiar scent and pheromones are used to signal the presence of a new hive to other bees.

Maelezo ya Majibu

(a) (i) Balanced diet: A balanced diet is a type of diet that contains all the essential nutrients in the right proportions to meet the nutritional requirements of an animal for normal growth and development. The essential nutrients include carbohydrates, proteins, fats, vitamins, minerals, and water.

(ii) Maintenance ration: A maintenance ration is the amount of feed an animal requires to maintain its body weight and meet its basic metabolic needs such as breathing, heartbeats, and body temperature.

(iii) Production ration: A production ration is the amount of feed an animal requires to produce milk, eggs, meat, wool, or any other product that the animal is raised for.

(iv) Malnutrition: Malnutrition is a condition that arises when an animal's diet lacks the essential nutrients required for proper growth and development.

(b) The effects of malnutrition on farm animals include:

(i) Poor growth and development

(ii) Reduced resistance to diseases

(iii) Reduced reproductive performance

(iv) Poor meat or milk quality

(v) Decreased feed efficiency

(vi) Increased susceptibility to environmental stressors

(c) Four nursery practices in the production of tomatoes are:

(i) Seed selection: Use only high-quality seeds from reliable sources to ensure good germination rates and healthy seedlings.

(ii) Seedbed preparation: Prepare the seedbed by loosening the soil, removing weeds and rocks, and adding organic matter to improve soil fertility.

(iii) Watering: Water the seedlings regularly and evenly to prevent water stress and promote healthy growth. (iv) Fertilization: Apply fertilizers, preferably organic, to provide essential nutrients for healthy growth and development.

Maelezo ya Majibu

(a) Four effects of specimen E on farm animals include:

1. Reduced feed intake: Specimen E can cause a decrease in appetite and feed intake in infected animals, which can lead to weight loss and decreased productivity.
2. Anemia: Infected animals may develop anemia due to the destruction of red blood cells by the parasite.
3. Weakness and lethargy: Infected animals may become weak and lethargic, which can also impact their productivity.
4. Death: In severe cases, specimen E can cause death in infected animals.

(b) The primary host of specimen E is the tsetse fly, and the intermediate host is the bloodstream of the infected animal.

(c) Three adaptive features of specimen F that enable it to survive in its host include:

1. Ability to evade the immune system: Specimen F is able to evade the immune system of its host, allowing it to avoid detection and continue to thrive.
2. High reproductive rate: Specimen F is able to reproduce quickly within its host, allowing it to establish a large population and compete with other microorganisms for resources.
3. Ability to adapt to changing environments: Specimen F is able to adapt to changing conditions within its host, allowing it to survive in a range of different environments.

(d) Three control measures of specimen E in livestock management include:

1. Use of insecticides: Tsetse flies can be controlled using insecticides, which can reduce the number of infected animals.
2. Improved management practices: Improved management practices such as regular veterinary care, nutrition, and sanitation can help to reduce the impact of specimen E on livestock.
3. Use of resistant breeds: Some breeds of livestock are resistant to the effects of specimen E and can be used to reduce the impact of the parasite on livestock populations.

Three control measures of specimen F in livestock management include:

1. Use of antibiotics: Specimen F can be controlled using antibiotics, which can kill the microorganisms and reduce their impact on the host.
2. Improved hygiene and sanitation: Improved hygiene and sanitation practices can help to reduce the spread of specimen F and other microorganisms in livestock populations.
3. Use of vaccines: Vaccines can be used to protect livestock against specimen F and other microorganisms, reducing the impact of these parasites on livestock populations.

Maelezo ya Majibu

(a) Specimen G is NPK or compound fertilizer Specimen H is wood ash and Specimen D is animal dung.

(b) The observable physical properties of the specimens are: Specimen G = NPK Hygroscopic. (i) The specimen is hard to touch, i:e; it is solid and strong. (ii) It is granular in nature and (iii) It is grey in colour and odourless.  
Specimen H wood ash
(i) It is grey in colour. (ii) It is smooth and velvety to touch  (iii) It is powdery in form (iv) It is dry and odourless.
Specimen D animal dung (i) It is dark brown or black in colour  (ii) It has bad odour. (iii) It is bulky in nature. (iv) It is always sticky and soft in its fresh form.

(c)The major nutrients supplied by the specimen are: Specimen G-N, - P-K, Specimen I-N,-P,-K.

(d) The methods of applying specimen H on the field are: (i) It can be spread on the farm before ploughing. (ii) It can be put in holes, before planting (iii) It can be placed at the base of the plant stem. (iv) It can be allowed to be in rows before ridging etc.

Maelezo ya Majibu

(a) 

(b) The area of the deep litter house is: Area = length x width Area = 36m x 10m Area = 360m² To calculate the number of broilers that can be reared, we need to divide the total area by the recommended floor space per chicken:

Number of broilers = Area / floor space per chicken

Number of broilers = 360m² / 0.36m²

Number of broilers = 1000 broilers

Therefore, the farmer can rear 1000 broilers in the deep litter house.

(c) The advantages of introducing legumes in a pasture include: 1. Nitrogen fixation: Legumes have the ability to fix nitrogen from the air and make it available to other plants in the pasture, which can reduce the need for nitrogen fertilizers.

2. Improved soil fertility: Legumes can improve soil fertility by adding organic matter to the soil and increasing the availability of nutrients.

3. Increased animal productivity: Legumes can provide high-quality forage for grazing animals, which can improve their growth rates and milk production.

4. Weed control: Legumes can compete with weeds for resources, reducing the need for herbicides.

5. Cost-effective: Legumes can be a cost-effective way to improve pasture productivity and reduce the need for expensive inputs like fertilizers and herbicides.

Maelezo ya Majibu

(a)(i) 

(a)(ii) The graph shows a positive correlation between the quantity of fertilizer used and the yield of tomatoes. As the quantity of fertilizer used increases, the yield of tomatoes also increases.

(a)(iii) From the graph, the most appropriate quantity of fertilizer to be applied on the tomato farm would be around 5 bags, as this is the point where the yield of tomatoes is at its maximum.

(b) Three effects of subsidy withdrawal on agricultural production are: reduced farm income, increased input costs, and reduced productivity.

(c) Four print media that could be used to disseminate information about a new variety of maize to farmers are: newspapers, farming magazines, flyers/brochures, and posters.

(d) Two insect pests of maize are: fall armyworm and maize weevil.

Two insect pests of orange are: citrus whitefly and orange fruit borer.

Maelezo ya Majibu

(a) Five reasons why the government should enact laws to regulate the use of land for agriculture are:

1. Environmental protection: Agriculture practices can have significant impacts on the environment, including soil erosion, pollution of waterways, and loss of biodiversity. Laws can ensure that farming practices are conducted in a sustainable manner that minimizes harm to the environment.

2. Food safety: Laws can ensure that the food produced by farmers is safe for human consumption by regulating the use of pesticides, herbicides, and other chemicals.

3. Land use planning: Laws can help to ensure that land is used efficiently and that there is enough land available for agriculture.

4. Animal welfare: Laws can regulate the treatment of animals on farms to ensure that they are treated humanely.

5. Economic benefits: Laws can create a level playing field for farmers by regulating the use of subsidies, price controls, and other measures that can distort markets.

(b) (i) The most appropriate type of farm power to use for tillage operations on a 10-hectare cocoa farm is a tractor.

(ii) Four reasons for using a tractor for tillage operations on a cocoa farm are:

1. Efficiency: Tractors are faster and more efficient than manual labor or animal-drawn implements, allowing the farmer to cover more ground in less time.

2. Power: Tractors have greater power and traction than animal-drawn implements, allowing them to work in tougher conditions and handle heavier loads.

3. Versatility: Tractors can be used for a range of farming operations beyond tillage, including planting, spraying, and harvesting.

4. Cost-effectiveness: Tractors can be expensive to purchase or hire, but their increased efficiency and productivity can lead to long-term cost savings for the farmer.

(c) One function of each of the following parts of a seed planter are:

(i) Seed tube: The seed tube delivers the seed to the furrow created by the furrow opener.

(ii) Furrow opener: The furrow opener creates a shallow trench in the soil for the seed to be planted in.

(iii) Hopper: The hopper holds the seed until it is dropped into the furrow by the seed metering device.

(iv) Seed metering device: The seed metering device measures out the correct amount of seed to be dropped into the furrow.

(v) Furrow wheel: The furrow wheel closes the furrow over the seed after it has been planted.

(d) Three machines used in processing crops after harvesting are:

1. Combine harvester: A machine that cuts, threshes, and cleans grain crops such as wheat, barley, and corn.

2. Thresher: A machine that separates grain from the straw and chaff of cereal crops such as rice, wheat, and oats.

3. Winnowing machine: A machine that separates the grain from the chaff by blowing air over the mixture, allowing the lighter chaff to be blown away while the heavier grain falls to the ground.

Maelezo ya Majibu

(a) The four causes of damage to maize during storage are:

1. Insects and pests: Insects such as weevils, moths, and beetles can infest stored maize, causing damage to the kernels.
2. Fungi: Fungi can grow on maize that is stored in damp conditions, causing mold and rot that can make the maize unfit for consumption.
3. High moisture content: Maize that is stored with a high moisture content can become moldy, or can sprout, leading to spoilage and loss of quality.
4. Physical damage: Maize can be damaged during storage due to rough handling, which can lead to broken kernels and reduced quality.

(b)

(i)

(ii)

1. Genotypic ratio: 1 TT : 2 Tt : 1 tt
2. Phenotypic ratio: 3 tall : 1 short

(c)

Mendel's first law of inheritance, also known as the law of segregation, states that individuals inherit two copies of each gene, one from each parent, and that these copies segregate during gamete formation, so that each gamete carries only one copy of each gene.

Mendel's second law of inheritance, also known as the law of independent assortment, states that the inheritance of one gene does not affect the inheritance of another gene, as long as the genes are located on different chromosomes.

(d) Two forage grasses are:

1. Timothy grass: Timothy grass is a cool-season grass that is commonly used for hay and grazing. It is known for its high yield and nutritional value, and is often used for feeding livestock.
2. Bermuda grass: Bermuda grass is a warm-season grass that is well-suited to hot, dry climates. It is often used for grazing, hay production, and erosion control, and is also used as turfgrass in lawns and athletic fields.

Maelezo ya Majibu

(a)(i) Specimen C is a maize plant with leaves showing a mosaic pattern/infection, tomato plant, showing leaf curl.
(ii) The causative agent for this condition is virus.
(iii) Specimen D is cassava leaf, showing leaf spot. The causative agent is fungus.

(b) Mode of transmission: For specimen C, the virus is transmitted by an aphid vector. For specimen D, the fungus is air-borne, water and rain splash

(c) Effects of each of the abnormalities on crops are: Specimen C (effects): (i) lt results in stunted growth of plants. (ii) It leads to reduction in yield of plants. (iii) It causes reduction in the photosynthetic area of the leaf.

Control measures include:
(i) early planting

(ii) removal and burning of infected plants

(iii) eradication of insect vectors

(iv) use of resistant varieties; and

(v) crop rotation For specimen K

effects
(i) lt causes reduction in yield of crop or plant.

(ii) It leads to the reduction in the rate of growth of plants.

(iii) It also leads to reduction in the photosynthetic area of the leaves.

Control measures include 

(i) application of fungicides 

(ii) use of resistant varieties

(iii) removal and burning of infected plants, and 

(iv) crop rotation.

(d) Other diseases of specimen C are

(i) cassava mosaic

(ii) cassava blight