Lesson Notes By Weeks and Term - Senior Secondary School 1

Date: 16^th – 20^th of January 2023

Class: SSS 1

Term: 2^nd Term

Week: 2

Subject: Agricultural Science

Topic: Crop Husbandry

Duration:45 minutes

Teaching Aid: A chart

Reference Books: Essential Agricultural Science for Senior Secondary Schools by O.A Iwena (pg 133-138)

ComprehensiveCertificate Agricultural Science for Senior Secondary Schools by L.A et Al (pg224-235)

Behavioural Objectives: By the end of this topic, students should be able to

1. Define crop husbandry
2. Discuss the husbandry of maize and rice

Presentation I

Step 1: Teacher revises last topic

Step 2: Teacher introduces and explains new topic

Step 3: Teacher writes note on the board

Step 4: Teacher evaluates students

Step 5: Teacher marks students' notes and give assignment

Previous knowledge: Students have been taught cultural practices

Content

Crop Husbandry

It deals with the various aspects of crops from seeds sowing, on field and off field operation,nuturing, harvesting, storage and marketing of the crop

MAIZE (Zea Mays)

Maize also called corn, is a member of grass family (Gramineae). It is a cereal crop which produces grains that can be used as food by human beings as well as livestock. The seed/fruit of maize is a caryopsis, i.e., it has its epicarp fused with the mesocarp.

Land Preparation

This is done by clearing the land or bush with cutlass, making ridges or heaps manually with hoe, or mechanically by ploughing, harrowing, and ridging.

Varieties/Cultivars

These include dent maize, fling corn, flour corn, pop corn, sweet corn and pod corn.

Climatic and Soil requirement

Maize requires a temperature of 26^oc - 30^Oc, rainfall of between 75cm – 150cm per annum and a well drained sandy loamy soil of pH6-7.

Method of propagation

Maize is propagated by seeds. The maize seeds can be panted manually by stick or cutlass, or mechanically by planter.

Planting date

Early maize is planted between March/April and late maize is July/August. Maize (early or late) is planted depending on location and rainfall.

Seedrate

The quantity of seeds required to plant one hectare of land is 25kg-30kg/hectare; two to three seeds are also recommended per hole. Quantity of seeds used usually depends on spacing or plant population desired.

Spacing

90cm x 30cm at one seed per hole or 75cm x 25cm at two seeds per hole.

Planting

Planting can be done manually, using cutlass or mechanically by planter at two or three seeds per hole at 2-4cm deep. Germination occurs four to seven days later.

Cultural practices

1. Supplying: Replanting of seeds to replace those seeds that did not germinate
2. Thinning: Removal of weak plant form a stand to give rise to one or two vigorous crop plants.
3. Fertilizer Application: Apply N.P.K 15:15:15 (200kg/Ha) (four bags) at planting. Also apply 250kg (five bags) or 150kg (three bags) of urea per hectare, five to six weeks after planting. Farmyard manure, poultry dropping/organic manure can also be applied as side dressing or by broadcast method.
4. Weeding: This is done three to four times at regular intervals. Weeding can be done manually by hoeing, cutlassing, etc; or chemically with the use of specified herbicides; or mechanically with medicine
5. Control of pest and diseases: This is done anytime at regular intervals or prevents it completely, using appropriate chemicals.

Maturity period

This takes up to two or three months (60-90 days) for wet maize, three to four months (90-120 days) for dry maize after planting.

Harvesting

Maize can be harvested by hand, sickle or corn picker by combined harvester. Maize matures 90-120 days after planting. It is harvested either green or dry. It is mostly harvested green for consumption when the silk dries and turns brown. Maize is harvested by plucking the cobs on a small scale and by machine.

Processing and uses

Maize can be eaten either boiled or roasted or processed into corn flour, corn flakes or used for corn meal, beer, being flour and livestock feed.

Storage

Dried maize cobs can be stored either in cribs, rhumbus or in a fireplace, on a small scale or in silos, on a large scale.

Pests of maize

1. Stem borers: the larvae bore holes into young stems and destroy the tissue, leading to low yield or death of the plant.

Control: spray with insecticides like Vetox 85, and practise crop rotation

2. Grasshopper: They eat up the leaves and other soft vegetative parts of the plants.

Control: spray with appropriate chemicals such as DDT.

3. Maize Weevils: This is field to store pest. Adults and larvae bore hole into grains and reduce them to powder.

Control:

1. Fumigate the store with BHC powder or phostoxin tablets
2. Early harvesting

Disease of maize

1. Corn smut: It is caused by a fungus (Ustilago maydis) which is spread by wind.

Symptoms: symptoms include galls on ears, leaves and tassels which later turn black.

Control:

1. Destroy diseased plants
2. Use resistant varieties

• Treat seeds before planting

2. Maize rust: It is caused by a fungus (puccinia Polysora), they cause red spot on leaves which eventually die.

Control

1. Uses resistant varieties
2. Practise crop rotation

• Practise early planting

3. Leaf spot: It is caused by a fungus (physoderma spp) which is spread by wind.

Symptoms: These include the death of parts of the leaves.

Control

1. Use resistant varieties
2. Apply the appropriate fungicide
3. Maize streak: it is caused by a virus which is transmitted by a piercing and sucking insect (leaf hopper).

Symptoms: symtoms include yellow streaking of leaves followed by stunting of deformation.

Control

1. Spray with insecticide to kill vector
2. Uproot and burn infected plant

• Practise early planting

RICE (Oryza sativa)

Rice is another popular cereal crop grown and consumed by nearly half of the world’s population. It is also a member of the grass family (gramineae). The seed/fruit of rice is a caryopsis, i.e., it has its epicarp fused with the mesocarp.

Land preparation

This is done either manually, using cutlass to clear the bush and remove stump and hoe to make ridges, or mechanically by ploughing, harrowing and ridging.

Varieties or cultivars

These include the swamp rice (toma, BG79 and GFBW4) and the upland rice (Agbede).

Climatic and soil requirement

Rice requires a temperature of over 20⁰C, 75cm – 120cm of rainfall for upland rice and over 250cm for swamp rice, and light fertile soil.

Method of propagation

Rice is propagated by seed. Rice can be propagated manually or mechanically.

Seed rate

65kg/ha at two to three seeds per hole

Planting date

Rice is planted in southern Nigeria around April and May, and between August and September in the north.

Planting

Rice can be planted by broadcasting, sowing or drilling of the seeds at 2-4cm deep.

Nursery practise

Swamp rice requires nursery which is done in fertile, water-soaked soil, seed are broadcast and germination begins after four to five days and the seedling are transplanted at between seven to eight weeks of growth to the field. Seeds are sown in nursery around May-June and transplanted in July-August to the field.

Spacing

25cm – 30cm apart, depending on variety.

Cultural Practices

1. Supplying and thinning

These can be done where applicable.

1. Fertilizer application

Apply 150kg or three bags of N.P.K fertilizer per hectare at planting by broadcasting

1. Weeding

Weeding is done to ensure rapid growth of rice.

1. Pest and disease

These should be prevented or controlled by spraying with appropriate chemicals.

Maturity period

Rice matures in four to seven months depending of variety.

Harvesting

Red heads of rice are cut off with knife, sickle or combined harvester.

Processing of rice

1. Sun drying

This is done immediately after harvesting for three to four days.

1. Threshing

This is the separation of the grains form the stalk by either beating with stick, threading with feet or by the use of mechanical threshers.

1. Winnowing

After threshing, the chaff or unwanted dust and remains of stalks are removed by winnowing. This is a fanning operation usually done by throwing the grains in the air to blow away the dust and other residues.

After winnowing, the grains of rice remain enclosed by the husk to form what is called paddy.

1. Parboiling

This process is used to reduce the breakage of grains during pounding. It also brings some vitamins to the outer layer of the grains and it also reduces the labour required to remove the husks. The paddy rice is heated putting it into boiling water for about 12-15 hours. The rice swells and the husks are forced apart. The parboiled rice is now sun-dried.

1. Hulling

This is the removal of the husks from the grains. The grains are pounded gently to remove the expanded husks. The husks are then separated from the rice by winnowing.

1. Polishing

In some cases, the paddy rice is threshed by machine, and polished. Polishing involves the use of specially designed machines to remove the husks and other layers covering the grains. The portion removed is known as rice bran which is very rich in protein and vitamins. Consumption of polished rice may cause vitamin deficiency disease called beri-beri due to the removal of the bran rich in protein.

Storage: Rice can be stored as paddy rice or in processed in silos or jute bags.

Pest of

1. Birds: These pests feed on the grains, leading to low yield of rice

Control: (i) employ children to scare the birds, (ii) use scare cows; (iii) early harvesting

2. Rodents: Cane rat and grasscutter cut the plants and seedling on the field leading to great loss.

Control: (i) set or use traps; (ii) fence round the farm

3. Rice weevils: This is a store pest. Adults and larvae bore into the grains and reduce them to powder.

Control: (i) fumigate store with phostoxin tablets

Diseases of rice

1. Rice Smut: it is caused by a fungus, (Tilletia Horrida) which is spread by wind. The grains turn into a mass of black spores.

Control: (i) Use resistant varieties; (ii) Use recommended fungicides to spray the crops.

2. Rice blight: It is caused by a fungus, (Piricularia Oryzae) spread through the soil. Longitudinal red or yellow spots develop on the leaves, leading to poor yield.

Control: (i) Avoid the use of heavy nitrogen fertilizer; (ii) use resistant varieties; (ii) use clean seeds.

3. Brown leaf spot: It is caused by a fungus. It causes small narrow brown spots which appear on the leaves.

Control: (i) Plant resistant varieties (ii) uproot and burn infected plants.

Evaluation: mention the uses of maize and rice products

Assignment: discuss two diseases of rice and maize