Agric Science Lesson Notes for SS 2 First Term – Edudelight Lesson note
WEEK SCHEME OF WORK AGRIC SCIENCE SS 2
1-2 Pasture and Forage Crops
3 Forest Management
5-6 Diseases of Crops
7-8 Pests of Crops
9 General Prevention and Control of Crop Pests
- Essential Agricultural Science for Senior Secondary Schools by O. A Iwana
- Prescribed Agricultural Science for Senior Secondary School.
- WAEC Past Questions and Answers Booklet
WEEK ONE AND TWO Date: __________
TOPIC: PASTURE AND FORAGE CROPS – LESSON NOTE
- Meaning, uses and types
- Factors affecting the distribution
- Management, practices of pastures
MEANING OF PASTURES AND FORAGE CROPS
Pasture: This is a piece of land on which forage crops grow.
Forage Crops: These are plants cultivated (or growing naturally) whose vegetative parts (leaves and stem) are fed on by livestock.
USES OF FORAGE CROPS
- They are used as livestock feeds
- They are used as cover crops which conserve soil moisture.
- They help in discouraging weed growth
- Some are leguminous in nature which enrich soil nutrient.
- For prevention of erosion
- Used as green manure
- Used for roofing farm steads
- As bedding materials
TYPES OF PASTURES
- Natural pasture: also called natural grassland or rangeland is piece of land on which grasses and legumes grow naturally on their own and are fed upon by farm animals
CHARACTERISTICS OR FEATURES OF NATURAL PASTURE
- It contains poor quality grasses and legumes.
- It contains soil types that are low in fertility or nutrients.
- It contains wide varieties of grasses and legumes, some of which may not be eaten by livestock.
- It has good regenerative ability.
- Crops here can withstand trampling.
- What are pastures and forage crops?
- List five uses of forage crops.
- Artificial pastures: this is also referred to as established or sown pasture is a piece of land that is where grasses and legumes are cultivated and managed by man to be fed by livestock.
CHARACTERISTICS FEATURES OF ARTIFICIAL PASTURES
- It contains high quality grass and legumes
- It contains no weed.
- Selected grasses and legumes are grown in adequate proportion
- Have high regenerative ability
- Can withstand trampling by farm animals.
QUALITY OF A GOOD PASTURE PLANT
- Ability to regenerate fast after being browsed
- Ability to withstand trampling
- It must be highly palatable
- It must possess high value of nutrients
- Ability to withstand extreme climatic condition
- It should have moderate moisture content or succulent
- It must have high leaf to stem ratio
- List five characteristics of a natural pasture.
- List five characteristics of artificial pasture.
COMMON GRASSES AND LEGUMES OF LIVE STOCK
COMMON NAME BOTANICAL NAME
- Elephant grass Pennisetum purpureum
- Guinea grass Panicum maximum
- Giant star grass Cynodon plectostachyum
- Carpet grass Axonopus compressus
- Spear grass Imperata cylindrical
- Bahama grass Cynodon dactylon
- Northern gamba Andropogon gayanus
- Southern gamba Andropogon tectorum
COMMON NAME BOTANICAL NAME
- Centro Centrosema pubescens
- Stylo Stylosanthes gracilis
- Kudzu or puero Pueraria phaseoloides
- Calapo Calapogonium mucunoides
- Mucuna Muccuna utilis
- Sun hemp Crotalaria juncea
FACTORS AFFECTING THE DISTRIBUTION OF PASTURE
- Climatic factors
- Soil or edaphic factors
- Biotic factors
The type of climate in an area influences the type of vegetation in the particular area e.g sudan type of climate will favour the growth of grass and legume while equatorial climate does not. The elements of climate which affects the distribution of pastures are rainfall, wind, temperature, relative humidity etc.
This refers to the level of fertility of the soil. Fertile soil enhances pasture growth and vice versa. Edaphic factors include soil PH, soil texture, soil structure, soil topography etc.
Biotic factors like diseases, pests, parasites, predators generally influence the distribution of pasture. Also human and animal activities such as bush burning and overgrazing will affect the distribution of pastures.
- List four grasses and their botanical name
- List four legumes with their botanical name
FACTOR AFFECTING THE PRODUCTIVITY OF PASTURES
- Persistence: ability to survive and spread by vegetative means.
- Aggressiveness: ability to compete favourably with other weeds.
- Resistance to trampling.
- Seed viability or profuseness or ease of propagation.
- Resistance to drought.
- Absence of pest and diseases.
- Good management.
- Adequate stocking.
ESTABLISHMENT OF PASTURES
Before pasture can be established, the following factors should be considered
- Adaptation of species
- time of maturity: should be short
- lifestyle of the species
STEPS IN ESTABLISHING A PASTURE
- Site selection.
- Clearing of land.
- Removal of debris
- Cultivation of site (land preparation).
- Planting of pasture crop.
- Promotion of tillers (more point of growth).
- Fertilizer application.
Example 1 page 184 of Essential Agricultural Science by O. A Iwena.
MANAGEMENT PRACTICES IN PASTURE
- Burning (when forage becomes fibrous to ensure regrowth of lush forage).
- Fencing to discourage overgrazing or facilitate rotational grazing.
- Fertilizer application or manuring.
- Regular weed control.
- Adequate pest and disease control.
- Adequate stocking.
- List three pasture grass and their botanical names.
- List three pasture legumes and their botanical names.
- List three factors affecting the distribution of pastures.
- List five factors affecting the productivity of pastures.
- List five management practices in pasture.
Produce a forage album containing no less than twelve mixtures of grasses and legumes to be submitted before sixth week.
Revision questions 4, 6 and 7 in Essential Agricultural Science for Senior Senior School, chapter 17, page 185.
- Which of the following is not a climatic factor affecting pasture distribution? A. Temperature B. Light C. Humidity D. Soil PH
- The following are edaphic factors except A. soil PH B. soil texture C. soil structure
D. relative humidity
- Diseases, pests, predators and parasites are ____ factors. A. biotic B. abiotic C. edaphic
- The act of re-planting pastures that fail to germinate is ______. A. thinning B. supplying C. weeding D. mulching
- The following are legumes except _____. A. centro B. stylo C. calapo D. gamba
- A. What is pasture?
B. Briefly discuss three factors affecting the productivity of pasture.
- A. Explain what is meant by natural grassland.
B. List five grasses and legumes each with their botanical names.
WEEK: THREE Date: __________
TOPIC: FOREST MANAGEMENT – LESSON NOTE
- Meaning of forest
- Forest reserve in Nigeria
- Importance or uses of the forest
- Management of the forest
Forest can be defined as a large area of land covered with trees and bushes, either growing wild or planted for some purposes which serves as habitat to various kinds of animals.
Forestry is the management of forest and forest resources.
Silviculture is the growing and cultivation trees.
Forest ecology is the scientific study of interrelated organisms in the forest.
COMMON FOREST TREES
Common forest trees found in the forest are Iroko, Obeche, Mahogany, Nigerian walnut, Ebony, Camwood, Opepe, Afara, Teak and Abura.
FOREST RESERVES IN NIGERIA
Forest reserves are large areas of land where plants, either growing naturally or planted are specially preserved for specific purposes.
SOME FOREST RESERVES IN NIGERIA
- Mamu River Forest Reserve in Anambra State.
- Omo Forest Reserve in Ogun State.
- Afi River Forest Reserve in Cross Rivers State.
- Okomu Forest Reserve in Edo State.
- Shasha River Forest Reserve in Ogun State.
- Zamfara Forest Reserve in Zamfara state.
- Sanga River Forest Reserve in Plateau state.
- What is Forest?
- List five common forest trees
IMPORTANCE OF FOREST AND ITS RESOURCES
The following are ways in which the forest and its resources are important to us. They are as follows:
- Provision of food.
- Provision of fuel.
- Provision of medicinal herbs.
- Provision of employment (lumbering).
- Forest serves as wind break.
- Formation of rain.
- Prevention of soil erosion.
- Addition of nutrients to soil.
- Home of wild animals.
- Forest serves as tourist centre.
- Provision of foreign exchange.
- It beautifies the environment and serves as tourist sites.
- Reduction of atmosphere pollution.
- Sources of raw materials such as pulp, timber, dye, gum latex etc.
MANAGEMENT OF THE FOREST
The following are management practices that will ensure a constant supply of timber in the forest:
- FOREST REGULATION:
These are laws promulgated by government in the form of edicts, decrees and bye laws to prevent people from exploiting or indiscriminate tapping of forest resources.
- The prohibition of bush burning
- Ban on indiscriminate cutting of timber trees
- Encouraging people to plant trees
- Ban or collection of leaves and firewood from the forest
- Ban or farming in forest reserves
- Ban or cutting down of under aged trees
- People are to obtain licences so as to secure the permission to enable them cut down trees for human needs.
- SELECTIVE EXPLORATION
This is the process of cutting or harvesting only mature trees in the forest
ADVANTAGES OF SELECTIVE EXPLORATION
- It ensures the concentration of selected species of timber in the forest
- It protects soil from erosion
- It ensures continuous supply of timber
- It serves as revenue base for the government
- It prevents indiscriminate felling of timber
This is the continuous or indiscriminate removal of trees without replacing them.
CAUSES OF DEFORESTATION
- Unfavourable climatic factors such as draught, wind blast etc
- Man’s farming activities such as bush burning, shifting cultivation etc.
- Timber exploitation
- Natural disasters
- Bad government policies
EFFECTS OF DEFORESTSATION
- It encourages soil erosion.
- It leads to reduction in fertility of soil.
- It reduces the amount of rainfall in an area
- It reduces soil moisture content
- It increases leaching of plant nutrient
- It destroys the microclimate and warms up the environment
- It may lead to desert encroachment
- List five importance of forest
- Explain selective exploration
Regeneration is the process of forest re-growth after it has been exploited. It is a deliberate effort to grow trees.
TYPES OF REGENERATION
- Natural Regeneration: in this type there is re growth of new plants from the old stump
- Artificial regeneration: this involves the planting of new forest seedlings in a deforested area.
ADVANTAGES OF NATURAL REGENERATION
- It is less expensive when compared with the artificial regeneration
- It does not require formal stages in plantation establishment
- It brings about the stabilization of natural ecosystem
- It does not require special management skill
This is the process of establishing forest plantations in any area.
ADVANTAGES OF AFORESTATION
- It leads to addition of organic matter
- It provides regular supply of raw materials e.g timber for industries
- It prevents desert encroachment
- It increases forest fauna (wild life) in the area concerned
- It prevents leaching of plants nutrient
- It increases soil moisture retention
- It increases the amount of rain fall
- It improves the soil structure
- TAUNGYA SYSTEM
Taungya system is defined as the planting of arable crops at early stage of forest establishment and the arable crops are harvested before the trees form canopies.
CONDITION NECESSARY FOR THE PRACTICE OF TAUNGYA SYSTEM
The conditions which may favour the practice of taungya system include:
- Scarcity of land
- Over population
- Government policies
- Low standard of living
ADVANTAGES OF TAUNGYA FARMING
- Varieties of crops are harvested
- There is availability of crop produce throughout the year
- When leguminous crops are used they fixed nitrogen to the soil
- Solves the problem of land scarcity
- It increases the income of the farmer
DISADVANTAGES OF TAUNGYA FARMING
- Reluctance in releasing fertile soil
- Cultivation of selected crops
- Competition between crops and trees
- Inability of some crops to survive
- Define Taungya farming
- List three advantages of Taungya farming
- What is regeneration?
- List the types of regeneration
- List the causes of deforestation
Find out the botanical names of ten common forest trees.
Revision questions 6 and 7 in Essential Agricultural Science for Senior Secondary Schools chapter 23, page 228
- The indiscriminate removal of trees is called____. A. aforestation B. deforestation C. taungya farming D. weeding
- The following are forest trees except ____. A. iroko B. obeche C. hibiscus D. ebony
- Process of establishing a forest plantation is called ____. A. afforestation B. deforestation C. taungya D. weeding
- The process of cutting only matured trees in a forest is called ______. A. selective exploitation B. selective exploration C. taungya D. aforestation
- The best soil for Agriculture is _____. A. loamy soil B. sandy soil C. clay soil D. silt soil
- A. Define forest
B. List ten uses of forest
- A. Define deforestation
B. State five effect of deforestation
WEEK: FOUR Date: __________
- Meaning of floriculture
- Importance of ornamental plants
- Common species of ornamental plants
Floriculture: is a discipline of horticulture that is concerned with the production and management of ornamental plants.
Ornamental plants are beautiful trees or shrubs which can be used to decorate our environments.
IMPORTANCE OF ORNAMENTAL PLANTS
- Sources of employment e.g florists.
- Serves as source of income.
- For expression of love and as gift on special occasions.
- For decoration.
- For fencing.
- For medicinal preparation.
- Sources of food.
- Purification of the air.
- For teaching and learning purposes.
- Provision of shades.
- Serves as wind breaks.
- Beautification of the environment.
- Sources of livestock feed.
- Serves as tourist centres.
- Source of revenue to the government.
- For preparation of dyes.
- What is floriculture?
- List seven uses of ornamental plants.
COMMON SPECIES OF ORNAMENTAL TREES, SHRUBS AND FLOWERS
- ORNAMENTAL TREES
- Frangi pani
- Neem cassia
- Royal palm
- Flame of forest
- India almond
- ORNAMENTAL SHRUBS
- Wild rose
- Dutchman’s pipe
- ORNAMENTAL FLOWERS
- Cana lily
- Morning glory
- Water lettuce
- Sun flower
CULTIVATION OF ORNAMENTAL PLANTS
The cultivation of ornamental flower includes:
- Selection of site that is well drained and easily accessible.
- Choice of planting materials which can be seeds or vegetative parts such as stems, roots, leaves (e.g bryophylum) and stolons
- Methods of cultivation
- Use of prepared bed
- Direct sowing to the soil
- Use of nylon bag
- Use of pots
- Provision of shades
- Organic manuring
- Regular weeding
- Regular watering
- List two each of ornamental shrubs, trees and flowers
- List three propagative material in cultivating flowers.
SOURCES OF PLANTING MATERIALS
The planting materials such as seeds, cut stems, leaves, stolons or rhizomes can be obtained from;
- Established private horticultural gardens
- Higher institution botanical garden
- Government owned horticultural centres
- Private houses and offices
- Imported ornamental trees and flowers
- Resort or recreational centres
MAINTENANCE OF HORTICULTURAL PLANTS/FLOWERS
- Provision of shades
- Regular watering
- Regular weeding
- Fertilizer application
- Regular pruning
- What are ornamental plants?
- List five examples of ornamental flowers
- List five examples of ornamental shrubs
- List five uses of ornamental plants
- Explain five maintenance practice in planting of ornamental crops.
Revision questions 5 and 6 in Essential Agricultural Science for Senior Secondary Schools Chapter 25, page 236
- The following are ornamental trees except _____. A. frangi poni B.balsam C. royal palm D. ixora
- Which of the following is not an ornamental shrubs? A. allamenda B.crotons C. hibiscus D.casuarinas
- The following are ornamental flowers except ____. A.justicia B. carnalityC. crotalaria D. balsam
- The following are legumes except ______. A. centro B. stylo C. calapo D. panicum maximum
- ______ are cultivated purposedly for feeding animals. A. arable crops B. ornamental crops C. forage crops D. farm trees
- A. What is Floriculture
B. State four ways in which ornamental plants is beneficial to man
2. A. List eight species of ornamental
B. State five effects of deforestation on the environment
WEEK: FIVE AND SIX Date: __________
TOPIC: DISEASES OF CROPS
- Meaning and causes of diseases
- Details of selected diseases
MEANING AND CAUSES OF DISEASE
A crop is a plant cultivated by man for a specific purpose. A plant disease is a deviation of the plant from the normal state of health, presenting outward visible signs. Diseases are caused by pathogens and enhanced by some physiological factors.
CAUSES OF DISEASE
Plant diseases are caused by pathogens. Pathogens are disease causing organism which passes through a regular cycle of development and reproduction. Examples of pathogens that cause plant disease are viruses, bacteria, fungi, parasitic worms and rarely protozoa. Some of these pathogens are carried by vectors and other agents.
Physiological factors such as nutrient deficiency in the soil, heat, presence of inorganic salts in the soil and soil moisture content has a major role to play in influencing plant susceptibility to diseases.
SELECTED DISEASE OF CROPS
|Name||Casual organism||Method of transmission||Symptoms and economic importance||Prevention and control measure|
|Maize Smut||Fungus (Ustilago maydis)||Fungus spores deposited on fruits||Reduced yieldGalls on ears, leaves and tarsels which later turn black||Destroy diseased plant.Use resistant varieties.Seed treatment.|
|Rice Blight||Fungus (Piricularia oryzae)||Airborne spores on leaves||Small longitudinal red spots on leaves which turn grey or brownReduced yield||Use clean seedsAvoid heavy use of nitrogen fertilizers. Use resistant varieties|
|Maize Rust||Fungus (Puccinis polysora)||Airborne spores deposited on leaves||Red spots on leave.Reduced yieldDeath of crop.||Early plantingCrop rotation Use resistant varieties.|
|Cercopora a Leaf spot of Cowpea||Fungus||Through Wind||Reddish brown spots on leavesLesions on leavesChlorosisDropping or falling of leaves.||Spray with fungicidesCrop rotationPlant resistant varieties.|
|Rosette disease of Groundnut||Virus||By piercing and sucking insect (Aphid)||Yellow leaves with mosaic mottling. Stunted plant with curled leaves.Wilting and death of plant.Shortening of the internodes.||Early plantingCrop rotationUse insecticidesUproot and burn infected plants.Use resistant variety.|
|Cassava Mosaic||Virus||Through piercing and sucking insect (whitefly) (Bemisia nigerensis) Infected plant cutting||Mottling of leaves or leaf curlDistortion of leaves and stems.Vein clearingStunted growth Development of yellowish pale areas alternating with green patches on the leaves or mosaic pattern on the leaves||Use resistant varietiesUproot and burn infected plant Spray with insecticide to kill vectorUse disease-free stem cuttings Farm sanitation.|
|Leaf blight of Cassava||Bacterium Xanthomonas manihotis||Infected cuttingsRain splashingInsectsTools||Blighting of leaves Wilting of plantFalling off of leavesReduced yieldCabker of stemDie-back of stem||Use resistant varietiesUse disease free cuttingsEarly plantingPractise crop rotation|
|Cocoa black pod disease||Fungus Phytophthora palmivora||Rain splashInsects||Brown spots on podRottening of podsEntire pod turns black Low yield||Remove and destroy infected podsRegular weedingSpray with fungicides eg Bordeaux mixtureAvoid over crowding of cocoa plants.|
|Coffee Leaf rust||Fungus||By windBy rain splash||Yellow or brown spot on leavesOrange powdery mass on the leafReduction in yieldDropping of leaves||Plant seeds from healthy plants Use resistant varieties.Spray with copper fungicides.|
|Black arm (bacterial Blight of cotton)||Bacterium||Through leavesStems near the ground||Angular spot on leavesBoll rotExudates from affected leavesRetarded growth and death of plant.||Seed dressingUproot and burn infected plants|
|Root Knot of Tomatoes/ Okra||Nematodes||Nematodes in soil||Knotting or galling of rootsRetarded growth Early death of plantReduction in yield||Soil sterilizationCrop rotationUse resistant varietiesUproot and burn infected plants|
|Damping off Disease of Okra||Fungus||Infected soil||Retarded growthCells become water loggedGradual wilting of plantDeath of plant||Spray with copper fungicideUse resistant varieties Sterilization of soil|
|Onion Twister Disease||Fungus||Infected soilWater splashInfected bulb||Twisting of leavesGrey patches on leavesReduction in yieldDeath of plant||Crop rotationUse resistant varietiesSpray with fungicidesEarly planting|
|Stored produce mould fungicides||Fungus||Infected seeds or fruits.High humidityBy Soil||Black mould on seeds and fruitsPungent smell.Sour tasteDecay of seeds and fruits in store.||Proper drying of seed before storageSpray with Maintain low humidity in storeRemove contaminated seeds before storage.|
- What is plant disease?
- List four common disease causing organisms.
GENERAL EFFECTS OF DISEASE ON CROP PRODUCTION
- Disease generally reduce the yield of crops
- They reduce the quality of crops
- They can cause malformation of parts of plants
- They can kill or cause death of a whole plant
- They cause reduction in the income of a farmer
WAYS BY WHICH DISEASE SPREADS ON CROP FARM
- By rain splash
- Through the use of contaminated equipment
- The use of infected planting materials
- Wind blowing pathogens to other crops
- Through animals
- Through insect vectors
- Through visitors to the farm
- Through weeds
GENERAL CONTROL OF CROP PLANT DISEASES
- Cultural method: the use of crop rotation, planting of resistant varieties, tillage practice, regular weeding, pruning etc. to control or prevent disease
- Biological control: this is the use of the natural enemy of the disease to reduce or totally eliminate the disease
- Chemical control: this involves the use of pesticides such as fungicides, nematicides, insecticides to prevent disease or control disease.
- What are pathogens?
- List two examples of pathogens.
- List three physiological factors that makes plants susceptible to diseases.
- List five air borne disease of crops.
Revision question 6 and 9 in Essential Agricultural Science for Senior Secondary Schools by O. A Iwena chapter 26, page 247.
- The following are pathogens except _____. A. viruses B. bacteria C. fungi D. algae
- Maize rust is caused by ______. A. bacteria B. fungi C. virus D. nematodes
- Rosette disease of groundnut is caused by ____. A. fungus B. virus C. bacteria D. nematodes
- Cocoa blackpod disease is caused by ______. A. virus B. bacteria C. fungi D. nematodes
- Root knoll of tomato is caused by ______. A. nematode B. fungus C. bacteria D.virus
- A. What is disease?
B. List disease pathogens
2 Discuss briefly the cassava mosaic disease under the following headings
A. Casual organism B. Transmission C. Symptoms D. Control
WEEK SEVEN AND EIGHT DATE: _________
TOPIC: PESTS OF CROPS
- Meaning of crop pest
- Types of crop pest
- Classification of insect pest
MEANING OF CROP PEST
A crop pest can be defined as any organism capable of causing damage to the crop.
TYPES OF CROP PEST
Important crop pest are grouped in to the following classes;
CLASSIFICATION OF INSECT PEST
- Biting and chewing insects: they possess strong mandible and maxillae (mouth parts) which enable them to bite and chew plant parts e.g termites, grasshoppers, leafworm, mantids, locusts and beetles.
- Piercing and sucking insects: they possess stong mouthparts called proboscis which enable them to pierce through plants and suck liquid materials from them. Examples are aphids, cotton strainers, mealy bugs, scale insects, capsids, mirids and white flies.
- Burrowing insects: they and their larva stage are capable of burrowing the tissue of the plant parts or fruits or seeds. Examples are bean beetles, stem borers, maize weevils and rice weevils.
- What are crop pests?
- List the three classes of insect pests.
IMPORTANT PESTS OF MAJOR CROPS
|Pest||Crops Attacked||Natures of Damages and Economic Importance||Prevention and Control Measures|
|Stem burrower||Cereals e.g. rice, maize, guinea corn.||Larvae bore holes into stemsThey eat up the tissuesThey weaken the plant||Uproot and burn infected plantSpray with insecticides e.g. Gammalin 20 Reduced growth and yieldEarly planting Crop rotation|
|Army Worm||Cereals e.g. maize||Larvae invade and eat up leaves and stemReduce photosynthesisRetarded growthReduced yield||Hand pickingSpray with insecticides. E.g. DDT|
|Pod burrower||Legumes e.g. cowpea, soyabeans||Larvae bore into the podThey eat up the seedsReduced yield||Crop rotationEarly harvesting Spray with insecticidesIntroduce diseases.|
|Aphids||Legumes e.g. cowpea, soyabeans||Stunted growthGalls on leavesVectors of disease e.g. rosette, mosaic disease of cowpea||Spray with insecticides to kill vectorUproot and burn infected plant|
|Leaf beetle||Legumes e.g. cowpea, soyabeans||They eat up the leavesReduce photosynthesisReduced yield||Spray with insecticidesUse pest-resistant varieties.|
|Cocoa mirids (capsids)||Beverages e.g. Cocoa||They inject toxic saliva into plantTransmits fungal diseasesReduced yieldStunted growth||Spray with insecticides e.g. Gammalin 20Regular Weeding|
|Yam beetles||Tubers e.g yam||Boreholes into yam tubersReduced yieldReduction in quality and market value||Dust yam setts with Adrin dust before plantingCrop rotation|
|Cassava Mealybugs||Tubers e.g cassava||Twisting of stem and reduced internodesSwelling of shootsReduced yield||Early planting Use pest-resistant varieties.Cutting treatmentSpray with insecticides|
|Green Spidermite||Tubers e.g cassava||They feed on the leavesReduce rate of photosynthesisReduced yield||Use biological controlSpray with insecticides|
|Variegated Grasshopper||Tubers e.g Cassava, yam||Adults and larvae eat up the leaves and stemReduce the rate of photosynthesisReduced growthReduced yield||Hand pickingSpray with insecticides e.g. Adrex 40|
|Cotton Stainer||Cotton||They pierce and suck sap from plantsProduce toxic salivaTransmit diseasesReduce quality of boll Leaf distortion||Hand pickingSpray with insecticides|
|Cotton bollworm||Cotton||Larvae feeds on the seeds of cottonCrop rotationDestroy the lint and reduce its qualityPremature fall of cotton boll||Spray with insecticides to kill insectsBurn cotton plant debris after harvesting.|
|Thrips||Vegetables e.g. Onion, tomato||Browning of leavesWilting of plantReduced yield||Spray with insecticides|
|Leaf rollers||Vegetable||Rolling and twisting of leaves Reduction in rate of photosynthesisReduced yield||Spray with insecticides e.g. Vetox 85|
|Leaf beetle||Vegetables e.g. pepper, okra and tomato||They eat up leaves and stemsReduced photosynthesis Reduction in yield and quality||Spray with appropriate insecticides e.g. Vetox 85|
|Bean beetle, grain weevils||Stored produce e.g. rice, cowpea and maize.||Boreholes into grains and eat them upReduce the quality of stored produceReduced farmer’s incomeReduce the market value of grainsReduce viability of insfested grains||Early harvestingProper storage of produceProper cleaning and fumigation of store with phostoxin tablets or with lindane dust.Store grains over fire placesProper drying of seeds to reduce moisture content and kill the eggs and larva of pests.|
|Birds||Rice, maize, millets and sorghum||Feed on grains in the fieldReduction in quality and yieldReduction in income of farmers||Use of bird scarer or scare crowUse of cage traps with baitsShooting with catapultDrumming or noise making on the farmUse of explosive mechanism at regular intervalsUse of avicidesFencing /Screening farms in greenhouse|
|Rodents e.g. bush rabbit, rats and squirrel||Rice, yam, cassava and fruits||They feed on cropsDestroy whole plantReduction in yieldIncrease in cost of production||Trapping with braits.Use of rodenticidesUse of string/wire trapsUse of predators e.g. dogs and catsClean weeding of farmsShooting and fencing Use of pit traps|
|Monkeys||Cocoa mango, banana, and orange||They eat up the fruits Reduce the quality of fruitsLosses to the farmer||Use trapsShooting with gun where possible.|
- List two ways of controlling cocoa mirids
- List two ways of controlling monkeys
ECONOMIC IMPORTANCE OF INSECT PESTS IN CROP PRODUCTION
- They destroy crops in the fields through their biting, chewing, boring, sucking and defoliation activities.
- They cause reduction in viability of stored produce
- Spot of injuries by insect pests predispose crops to pathogen attack
- They increase the cost of production as they are being controlled
- They render vegetables and fruits unattractive and unmarketable
- Some are of vectors of disease
- The profits of farmers are reduced
- They reduce the quality of produce either in the store or in the field
- They generally reduce the yield of crops
- They can also cause total death of crop plants.
- What are pathogens?
- List five pathogens you know
- List four economic importance of insect pest
Revision questions 3 and 8 Essential Agricultural Science for Senior Secondary Schools Chapter 26, page 247
- _____ is responsible for damages in crops. A. weeds B. water C. air D. pests
- The following are rodents except _____. ?A. rat B. grasscutter C.squirrel D.monkey
- The following are bitting and chewing insect except ____. A. termites B. capsids C.locust D. beetles
- Stem burrowers will attack A. cereals B. legumes C. tubers D. spices
- Cotton strainers and meleabugs are examples of _____ insects. A. biting B. chewing C. piercing D. burrowing
- A. What are pests
B. List the five types of pests
2. A. List five effects of pests in crop production
B. List three control measures of plant disease
WEEK NINE DATE: _________
TOPIC: GENERAL PREVENTION AND CONTROL OF CROP PESTS
- Physical control
- Chemical control
- Biological control
- Cultural control
METHODS OF PEST CONTROL
Crop pests can be prevented or controlled through the following methods:
- Physical control
- Cultural control
- Biological control
- Chemical control
This involves the physical removal of pests by:
- Hand picking of insects and larvae
- Setting traps to catch rodents
- Shooting rodents with gun
- Fencing round the farm with wire nets.
- Use of scarecrow.
- List the methods of pest control
- List three ways by which pests can be removed physically
This method involves the use of farm practices to prevent or control pests, examples of cultural control are:
- Practicing crop rotation
- Use of pest resistant varieties of crops
- Appropriate tillage operations
- Burning crop residues
- Timely planting of crops
- Proper weeding or sanitation
- Timely harvesting
- Close season practices (no living plant is allowed for a certain period).
This involves the introduction of natural enemies of pests to control or keep the pests population under control. Such enemies eat up or feed on these pests, thereby reduce the population of the pests.
- List two cultural control of pests
- Explain biological pest control
This involves the use of chemical called pesticides to control pest of crop plants. Examples of pesticides are insecticide, rodenticide, avicide etc.
Examples of chemicals used to control pests are:
- Insecticides – for controlling insect pest e.g grasshopper
- Rodenticides – chemical control for rodents such as rats
- Avicides – for controlling bird pest
- Nematicides – chemical used to control nematodes. E.g worms
FORMS OR GROUPS OF INSECTICIDES
The four groups and the mode of action are:
|Group||Mode of action|
SIDE EFFECT OF THE VARIOUS PREVENTIVE AND CONTROL METHOD OF DISEASE AND PEST OF CROPS
Use of these control methods have their effect, these effects includes
- Death of some beneficial insect and soil organism, toxic exposure to animals and man, chemical residue in the environment, washing away of chemicals into aquatic life e.t.c when chemical control method is employed.
- Organisms introduced may attack cultivated crops or stored grains, predators might not feed on targeted pest and deviate to feeding on beneficial organisms, the activities of new organism might cause an ecosystem imbalance when biological control method is employed.
- When cultural control method is employed, the use of bush burning method might get out of hand thereby destroying soil structure, spread to other farms, loss of organic matter and lead to death of beneficial microbes.
- What are insecticides?
- List the three forms of insecticides and their mode of action
- What are avicides, rodenticide and nematicides are used to control
- List five economic importance of crop pests.
Revision question 10, 14 and 16 Essential agricultural science for senior secondary schools chapter 26, pages 247-248.
- Avicides are used to control _____. A. rodents B. birds C. insects D. pests
- The mode of action of liquid insecticide is_____. A. contact B. systemic C. stomach D. fumigation
- Weevils are _____ insects. A. biting B. chewing C. burrowing D. piercing
- The following are pests except. A. rodents B. earthworm C. monkeys D. nematodes
- The following are biting chewing insects except _____. A. butterfly B. locust C. grasshopper D. cricket
List two side effects each of using
- Cultural control of pests
- Biological control of pests
- Chemical control of pests
- Physical control of pests