Field Crops Production
Level II
Unit of Competence: Assist Field Crop Establishment and maintenance
Module Title: Assisting Field Crop Establishment and maintenance
LO1: - Prepare for field crop establishment and maintenance operations
LO2: - Prepare the site for crop establishment and maintenance
LO3: - Carryout establishment and maintenance operations
LO4: - Complete establishment and maintenance operations
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Introduction
Before start to learn the competence’s outcome you should have to understand some basic
concepts like meanings of field crops and crops which are categorized under field crops which
make you familiar with the concepts of competence’s outcome.
Crops: are plants that are cultivated (managed) by human being for his special economical
purposes. Proper work or production process from land preparation to postharvest handling of crop
is an important in increasing crop yield and reduce crop losses by different agents.
Crop production: is a rising of crops under field condition to get grain, fruits, roots and tuber,
leaves, sugar, fiber, timber, flowers, spices etc.
Crop classification
According to range of cultivation
 Garden crops: crop plants grown on small scale in the garden. they are specially called as
kitchen garden, flower garden, backyard garden
 Plantation crops: crop plants grown on large scale. They are permanent in nature. Eg.coffee,
tea, cacao, sugarcane, tobacco, cotton etc…
 Field crops are also called “Agronomic crops”. They are mostly annual herbaceous plants
that are grown under extensive or large-scale culture. Are classified as cereals, seed legumes,
oil crops, root and tuber crops, sugar crops, latex and rubber crops, pasture and forage crops,
and fiber crops under field crops.
According to botany: botanical classification is based on similarities of plant parts.
 Graminacea family: - grass family includes wheat, barley, oat, rye, rice, finger millet, maize,
sorghum, pearl millet. They can be annual, biennial, or perennial and they posses narrow leave
with parallel veins and fibrous roots.
 Leguminacea family: they possess broad leaf and tape root system which bears bears nodules.
Their seeds are borne in pods. Eg. Haricot bean, field pea, chick pea, cow pea, soya bean,
alfalfa etc…
According to season
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 Meher season crops: The crops require cold and dry weather for their growth and
development. They are long day plants planted in July-September and harvested November –
January. E.g. wheat, barley, oat, chick pea, etc.
 Belg season crops: they require dry and hot weather for their growth and development. They
require long day length for flowering. They are sown in February-march and harvested in May
– June e.g. sesame and ground nut
According to duration of life cycle
 Annual crops: crops which complete their life cycle within one growing season or one
year. E.g. wheat, barley maize, faba bean etc
 Biennial crops: crop plants that complete their life cycle in two successive season or two
consecutive live years. In the first season/year is for vegetative growth and for the second
season/year is for reproduction (flower, seed and fruit production). E.g. cabbage, carrot,
sugar beet, radish
 Perennial crops: the plants that complete their life cycle more than two years e.g. sugar
cane, Napier grass, tree fruits, grape etc..
Economic or agronomic classification of crops
 Cereal crops: belonging to the grass family grown for their edible seeds/grains. Eg. Rice,
wheat, barley, oat, rye, maize, sorghum, millet, teff etc
 Grain legume: belonging to the legume family grown for their edible seeds. E.g. faba bean,
field pea, lathyrus pea, chick pea, haricot bean cow pea, etc. they are rich in proteins
 Oil crops: grown for their own oil and are two types
 Edible oil eg. Ground nut, soya bean, sesame, sunflower, safflower, noug, linseed, rape seed
and Ethiopian mustard etc
 Non edible oil; e.g. Caster bean
 Sugar crops: which have a capability to produce sugar eg. Sugar cane and sugar beet
 Root and tuber crops: crops grown for their enlarged roots and tubers e.g. Irish potato sweet
potato cassava, yam taro cocoyam, beet root, ensete, etc..
 Fiber crops: crops grown for their own fiber e.g. cotton, sisal,
 Drug crops: their product is smoked and chewed for their stimulated effect e.g. tobacco.
 Beverage crops: crops used for the preparation of alcoholic drinks, which have stimulating
effect when consumed. e.g. barley and geisha
 Stimulant crops: used as a source of stimulant e.g. tea, coffee, chat, cocoa
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 Vegetable crops e.g. cabbage, lettuce, pumpkin, cucurbits melon, pepper, onion, tomato, etc..
 Fruit crops: e.g. papaya, banana, avocado, mango, orange, lemon, mandarin, pine apple,
apple, peach, passion fruit, grape, etc…
 Spice and condiments crops: used to increase the taste, flavor and coloration of dishes e.g.
ginger, turmeric, garlic, korerima etc…
 Medicinal crops: crops used raw material for pharmaceutical and perfume industries
LO1: - Prepare for field crop establishment and maintenance operations
1.1. Planning for field crop establishment and maintenance
Careful planning for establishment of field crops is an essential part of good production of field
crops. During establishment of field crop one of the earliest decisions that must be taken is where
to locate the farm (correctly selection of the site). It means where in the country or region or place
the farm should be located.
Factors to consider in the final decision of the farm site are: Climate (RF, temperature, light, etc.)
Climate largely determines the type of vegetation that grows naturally in any part of the world and
the kinds of agriculture that are possible. The three most important factors in climate from the
standpoint of plant response are temperature, water supply/precipitation/ and light.
There are also other factors like humidity, solar radiation, wind and atmospheric gases but
generally they are of less influence than the three mentioned.
Temperature is often the factor limiting the growth and distribution of plants. It influences the
rate of growth, development and number of flower that produce seeds. When temperature is below
15 oC frost or pale-yellow color of the plant parts occur. In any given locality, the length of
growing season is known to vary as much as 30 days for different years. The ranges of maximum
growth of the plant are 15-32 oC.
Water supply/irrigation availability
Water supply is the most important factor in determining the distribution of a crop plant. Although
total annual precipitation is important, its distribution plays an essential role in crop production. In
case of plant growth for their seed, the most critical period or the period of greatest need for
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moisture, is when fertilization of the flowers is taking place. Crop plants differ in their water
requirements, even though they are almost all require an average amount of water.
Light: - Light affects the development of crop plants mainly through affecting their structural
development, their food production and the time required for certain species or varieties to produce
seeds. Many plants are influenced by the length of day, especially in regard to flowering, fruiting,
and the production of seed. This effect of light on plants is known as photoperiodism. Some plants
are known as long day plants and other as short day. The long day plants need a comparatively
long day for flowering and their vegetative growth increases when the days are short. Wheat and
oats are among the long day plants. The short day plants such as maize, soybean and sorghum
achieve their vegetative growth when the days are long and flower and produce seed when the
days are short.
 Soil factors
Soil factors are nutrients and water, soil moisture, soil temperature, soil air, soil reaction (acidity or
alkalinity).
Soil moisture: - the amount of soil moisture has impact on performance of individual plants. If
soil pores are completely filled with water, water logging condition is happen. Then water logging
resulting in shortage of oxygen, leaching of plant nutrients, poor germination or nil, stunted
growth, failure of seed formation, yellowing of leaves etc.
Soil temperature: - it is another soil factor that determining the growth of plants. It influences the
rates of absorption of water and solutes, germination of seeds, growth of seeds, growth of roots,
and decomposition of organic matter.
Soil reaction (soil acidity or soil alkalinity): - Some soils contain such as an excess of soluble
salts that they interfere with crop growth. Plants are varying in their tolerance of alkaline soil or
acidic soil. Among the tolerant crops are sugar cane, sugar beet, cotton, rye and many of the
grasses. Grasses or cereals seem to be more tolerant than the legumes. Many crops are tolerant to
acidic soil conditions and often make satisfactory growth. Some of these crops are tobacco, cow
pea etc. Most legume crops differ greatly in their adaption to acid soil most grow well on slightly
or moderately acidic soil. Small grains, maize, some legume are broadly tolerant, growing well
within the pH ranges 5.8 to 7 or slightly or above.
 Altitude/Elevation
The choice of a crop to be cultivated in a given locality is determined by its altitude. Based on
altitude or elevation field crops are classified in to different groups. These are:  Wurch: - greater than 3500m a.s.l.
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 High land (Dega):- 2500-3500m a.s.l.
 Medium land (Woynadega):- 1500-2500m a.s.l.
 Low land (kola):- 500-1500m a.s.l.
 Desert (harrur):- less than 500m a.s.l.
 Pests: - the presence or absence of particular diseases or pests that attack the
proposed crops should be checked.
 Availability of inputs and other materials, tools and equipments
Different inputs like land, planting materials, labor, etc and other materials like tools and
equipments should be available.
 Accessibility: - The site should be accessible to all times and preferably be near the
road, markets, processing facilities and ease for supervision.
1.2. Selecting and preparing machinery, equipments and tools
Before starting to establishment of field crops, all necessary tools and equipments should be
gathered. These should include a minimum of:
Tractors and associated land preparation
Seeding equipment,
Cultivators and Fertilizer spreaders,
Seeding or planting machinery bagged or bulk seed,
Field tool boxes, cane knives, and planting trailers.
1.3. Identifying OHS and environmental hazards
During establishment of field crops, some activities can be potentially toxic or hazardous to human
beings and pollutant environmental conditions. Occupational and environmental hazards may be
occurred through use of machinery, moving machinery and machinery parts from one place to
another, plant debris, chemicals and hazardous substances, manual handling, solar radiation, dust,
and noise, the contamination of off-site ground water or soils from solids, debris, nutrients or
chemicals, land disturbance, spread of noxious weeds and water run-off. Identifying of these
factors and following of occupational health and safety required is very important.
1.4. Selecting suitable personal protective equipments
During establishment of field crops you should have to follow safety required to avoid hazards.
Skin contact with crop residues which may be toxicants during clearing, working with sharp
machinery and use of other chemical substances must be avoided. Wearing of persons engages
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like: -hat, boots, overalls, gloves, goggles, respirator or face mask, hearing protection, and
sunscreen lotion is a must.
LO2: - Prepare the site for crop establishment and maintenance
Clearing and disposing wastes
The first step in preparing a virgin land for establishment of field crops is clearing the land to
remove existing vegetation, either completely or partially. The amount of vegetation removed
during land clearing is depends on: The production region:- grass land, shrubs or forest land
 Production system:- mechanized or non-mechanized
 Crops to be grown:- cereals or legumes or forage crops or fiber crops, etc
Once the site for the farm has been selected and acquired, the farmer proceeds with clearing. It
involves
 Cutting down the vegetation
 Removal of dead plant materials(collecting and burning)
 Stumping:- removal of stumps is used to facilitates cultivation of the land and to control
infestation of diseases and insect pests
Operating equipments and tools
For establishment of field crop selecting and preparing materials, tools and equipments is the first
steps. Next to this checking serviceability of materials, tools and equipments is one the important
ways. After serviceability of material, tools and equipments has been checked operating (making
ready) machinery, tools and equipments are the necessary steps which make land preparation
activities more easy and suitable.
Implementing land preparation activities
After the land has been cleared various tillage operations should be carried out. Tillage includes all
operations and practices used for the purpose of modifying the physical characteristics of the soil.
These are:a) Plowing/Digging: plowing is initially done to open the compact or hard soil. During this
operation the soil is inverted, weed uprooted and stubbles incorporated into the soil. The depth of
digging varies from 10 to 30 cm.
It has different purposes like:
 Cutting and turning the soil
 Loosening the soil and good root penetration
 Aerating the soil and making it permeable
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 Reducing weeds and insect infestation
 Incorporating organic matter and soil amendments to improve the structure of the soil
 Shaping soil: - tillage is done to create raised beds for planting or to create furrows for
irrigation.
 Erosion control:- like in conservation tillage
b) Harrowing/pulverizing: if the lumps (clods) of soil left after digging are too large, they must
be broken up before planting/sowing if broadcasting and before furrow preparation if row methods
of sowing.
Purpose of harrowing are:
 Cutting the clods and sods to a considerable depth
 Producing fine seedbed and leveled soil
 Obtaining weed free soil
c) Leveling: - is done to improve surface drainage, for installation of irrigation equipment, or to
facilitate the use of farm machineries and equipment.
Applying soil treatments/amendments
Lack/shortage of rainfall in drier regions results in an accumulation of salts (cations like Ca ++,
Mg++, Na+, etc). When such accumulation exists the production of crops may be uncertain, or even
impossible, over relatively large areas. At times the excessive may be leached out by irrigation or
corrected by the addition of gypsum or sulfur. It often may happen in some area that soil acidity is
so great lime must be applied before satisfactory crop production is achieved. Low soil fertility
may reduce the productivity of soil. Therefore, application of organic fertilizer like (compost,
FYM), inorganic fertilizer and planting of a temporary or permanent cover crop is a good way.
Implementing crop protection
To protect soil erosion which may be occur through winds and water (rain drops) implementing
crop protection techniques like wind protection such as permanent shelter belts or temporary
plantings of plants and mulching the soil by straw materials, cover crop or any vegetative material
is necessary.
Selecting planting pattern.
Based on types of crops, sowing/planting methods/pattern can be divided in three. These are
broadcasting, drilling and dibbling. The sowing method is determined by the crop to be sown.
 Broad casting: It is the scattering of seeds by hand all over the prepared field followed by
covering with wooden plank or harrow for contact of seed with soil. Crops like wheat,
paddy, Sesame, coriander, etc. are sown by this method.
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Advantages:
1) Quickest & cheapest method
3) Implement is not required,
2) skilled labour is not uniform.
4) Followed in moist condition
Disadvantages:
soil.
1) Seed requirement is more
4) Spacing is not maintained within rows &
2) Crop stand is not uniform.
lines, hence interculturing is difficult.
3) Adequate moisture is not present in the
 Drilling or Line sowing: It is the dropping of seeds into the soil with the help of implement such
as seed drill, seed-cum-ferti driller or mechanical seed drill and then the seeds are covered by
wooden plank or harrow to have contact between seed & soil. Crops like Jowar, wheat ,tef
&wheat etc. are sown by this method.
Advantages:
 Seeds are placed at proper & uniform depths
 Along the rows, interculturing can be done
 Uniform row to row spacing is maintained
 Seed requirement is less than ‘broad casting
 Sowing is done at proper moisture level.
Disadvantages:
1) Require implement for sowing
2) Plant to plant (Intra row) spacing is not maintained
3) Skilled person is required for sowing.
 Dibbling: It is the placing or dibbling of seeds at cross marks (+) made in the field with the
help of maker as per the requirement of the crop in both the directions. It is done manually
by dibbler. This method is followed in crops like Groundnut, Castor, and Hy. Cotton, etc.
which are having bold size and high value.
Advantages:
1) Spacing between rows & plants is maintained
2) Seeds can be dibbled at desired depth in the moisture zone
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3) Optimum plant population can be maintained
4) Seed requirement is less than other method
5) Implement is not required for sowing
6) An intercrop can be taken in wider spaced crops
7) Cross wise Intercultivation is possible.
Disadvantages:
1) Laborious & time consuming method
2) Require more labour, hence increase the cost of cultivation
3) Only high value & bold seeds are sown
4) Require strict supervision.
LO3: - Carryout establishment and maintenance operations
3.1. Carryout establishment and maintenance operations
3.1.1. Selecting planting materials
Seeds are the pre-operational unit of flowering species and the economic part of grain crops, consists
miniature plant called embryo. To produce high quality and quantity of field crops selection of good
seeds are very important.
Good seeds have the following characteristics:  Pure( true to type)
 Viability/good germination capacity
 Matured, well developed, uniform size,
shape, color , texture etc
 Should contain the required amount of
moisture
 Fitting within the usual period of the raining
season
 Health, clean, and free from inert matter
 High and stable yield
 Free from other crop seeds
 Resistance to insect pests and diseases
 Free from any pest and seeds borne diseases
 Uniform heading and fruiting
 Should be whole, not broken, crushed,
 High oil, protein or starch content
shriveled, rotten etc
Seed damage may be caused by mechanical injury, insects, fungi, and bacteria. The quality of seed is
governed by its purity, viability, germination capacity, seed health (pathogens) test, genetic purity test
etc. If seed lacks in any of the characteristics it may becomes unfit for sowing.
a. Seed purity test (Physical purity test): -Seed purity is the percentage of pure seed (only the seed of
the desired kind without contaminants) in the sample tested. The contaminants includes:Seed of others: - like wheat seed may be found in barley seeds.
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Weed seed
Inert materials: - includes materials (foreign matter) such as small stones, pieces of wood, and other plant
materials.
b. Seed viability test: - Seed viability is the capacity of seeds to germinate. A viable seed is one capable
of germinating to produce a health, normal seedlings. It is not enough to tissues in the seed to be viable;
the seed must able to grow to produce seedlings.
c. Seed germination test: - See germination is the sequence of events in a viable seed starting with the
absorption of water that leads to growth of the embryo and development of seedlings. When the seeds are
placed in proper conditions of moisture, temperature and oxygen, the growth of embryo or germination
commence. The degree to which germination has been completed is usually expressed in percentage,
normally determined at time intervals of germination period in terms of germination power and
germination capacity.
Germination %
=
Numbers of germinated seeds x 100%
Numbers of planted seeds
d. Seed health (Pathogen) test: - It evaluates the presence of insect on the seed like change in color,
presence of spots etc, and then placed under optimum germination condition for germination to occur.
3.1.2. Treating planting materials
Seed treatment is the process of applying physical, chemical or biological treatment to the seed to keep it
viable and health.
Physical seed treatment
It includes subjecting seeds to solar exposure, immersion in conditioned water etc. To induce higher
germination, the seeds may be soaked in water before sowing or may be exposed to warm temperature.
Early rooting may be induced by treating seeds with IBA or GA solutions. To induce or facilitates
sowing and better germination in cotton seed treated with sulphuric acid (H2SO4).
Biological Seed treatment
It includes the treatment of seeds with microbial cultivars such as that of Rhizobium to inoculate the
seeds with microbial cultivars, to fix atmospheric nitrogen and release to the soil.
Chemical seed treatment
It includes treating seeds with fungicides, insecticides, nematocides etc.
3.1.3. Handling and transporting planting materials to the site
Seed handling is the procedure of drying, cleaning, grading, treating and storing seeds. Care to be taken
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 Temperature is controlled under 400c
 Do not dry seeds too fast
 Don’t make seeds over dry
 Avoid seed mechanical damage
 For storage of sowing seeds the following condition should be fulfilled:
 Low seed moisture content (wheat and barley (13%), maize (14%), oil crops (10 %) etc.
 Maintain low temperature by installing ventilators
 Effective pest control
 Low relative humidity
During transporting sowing seeds from storage area to the site appropriate care should be undertaken to
avoid damage of seeds.
3.1.4. Carrying out planting operations
After selecting the appropriate cultivars and preparing the land, there are four major procedure/decisions
to make towards crop establishment.
3.1.4.1. Depth of seed placement (sowing depth)
If seeds are sown at different depth , germination will be uneven, resulting an uneven crop stand, which
will, in turn affect later crop production activities such as harvesting( crop mature unevenly). Shallow or
deep sowing result in lesser population, as all seeds will not germinate together. The crop shows uneven
spread of plant with large number of gaps, and serious weed problem. It is therefore, essential to sow the
crop at optimum depth for obtaining good crop stand.
Factors that influence the sowing depth
Seed size: - large seeds have more food reserves and can emerge from lower depths, in the soil while
depending on stored energy. Small seeds have limited food reserved and are placed at shallow
depths.
Bigger seeds like groundnut, castor bean can be planted deeper
Small sized seeds like teff, tobacco have to be planted at shallower depth.
The optimum depth of most field crops is 3-5cm
Types of seedling emergence: - species with epigeal germination need to emerge above the soil, to
commence seedling establishment. If placed too deeply in the soil, emergency may be greatly
delayed and seeds may rot in the process.
Soil type: - heavy soil (clay) is poorly drained, poorly aerated, and prone to crusting. Light soil(
sandy) drain freely and are prone to drying so that seed may be planted deeply
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Depth of soil moisture
Economic factor:- cost of seeds
Quality of seed bed:- on fine seed bed fine seed is planted
Plant factor:- like rate of root penetration, type of root system( tap root or fibrous root) etc
3.1.4.2. Determining Optimum Sowing Time
Field seeding should be done at the appropriate time. Field cropping is a seasonal operation. Weather
conditions are not conducted for cropping all year round. Many crop production regions have a large
major cropping season, and a shorter minor cropping season. Time of seeding is especially critical if
production is to be rained. The optimal time of seeding is chosen for several reasons.
Factors that affect time of sowing
 Optimal soil condition for germination:-at certain times in the growing season.
 Occurrence of disease and insect pest: - is diseases and pest that destroy seeds and seedlings are
more prevented at certain times in the growing season.
 Rain fall has a dominant influence in crop production: - the effect of moisture on crop grown can be
attributed to at least two of its aspects.
 Distribution of rainfall: during germination and emergence of seedling, the amount of moisture
needed is much less but sensitive
 Temperature: - temperature is also an important factor in limiting the growing of certain crops.
Each plant has its own temperature range i.e. minimum, optimum, and maximum for growth
 Day length:-long day plant need relatively long flowering time, but they increase their vegetative
growth at short day. Short day plants need short interval of light for flowering
 Market
 Cropping system
 Availability of labor
 Time taken to maturity
3.1.4.2. Deciding Recommended Seedling Rate
Factors that influence plant population (seed rate)
 Size of the cultivar:- Dwarf, determinate, indeterminate growth habit, tillering, and non-tillering etc
 Amount of moisture available:-most crops are seeded at greater rates under dry land than under
humid or irrigation conditions.
 Soil fertility: - on fertile soil less seeding rate is needed.
 Number of crop grown together: - the number of crop crowns together, the more rates of seed
needed.
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 Planting methods: - broadcasting need more seeding rate than other methods.
 Germination capacity of the seeds:- if the germination capacity of the seed is higher, the lesser
seeding rate needed.
3.1.4.4. Selecting proper sowing/planting methods
Based on types of crops sowing/planting methods can be divided in three. These are broadcasting,
drilling and dibbling.
1. Broadcasting: - the seeds are spread uniformly over well prepared land by plowing or planking. It
may be done by hand or seed driller. When the number of plant per unit area is more important than
definite spacing from plant to plant, this is usual method of sowing.
2. Drilling: - is the practice of dropping the seeds in the rows or lines. Furrows at specified distance,
covered with soil and are compacted.
3. Dibbling or planting: - It consists of putting or placing individual seed or seed materials in a hole
or pit, made at pre-determined spacing and depth by manual or with the use of mechanical dibbler
or planter.
3.2. Carryout maintenance operations
Maintenance operations includes:o Applying fertilizer
o Applying irrigation
o Controlling pests (insects, weeds, diseases and rodents)
3.2.1. Applying fertilizer
Fertilizer is a natural or synthetic chemical substance or mixture used to enrich soil so as to promote plant
growth. Plants require more than a dozen different chemical elements and these elements must be present
in the soil to allow an adequate availability for plant use. For example, nitrogen can be supplied with
equal effectiveness in the form of urea, nitrates, ammonium compounds, or pure ammonia. There are
sixteen (16) essential elements that are requires by most plants. These are: non mineral elements (C, H2,
and O2 obtained from the air and water), Macronutrient/Major elements (N, P, K, Ca, Mg and S) and
Micronutrients/Trace/minor elements (Bo, Cl, Cu, Fe, Mn, Mo and Zn)
3.2.1.1. Purpose of fertilizer application
o It promotes greater plant growth or better crop quality
o It maintains soil fertility, indirectly reduce soil erosion
o It compensates some elements to the soil.
3.2.1.2. Principles of fertilizer application
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Before application of any fertilizer for field crops you should be known some basic principles of fertilizer
application like:1. Frequency of fertilizer application: - Depending on capacity of soil to retain nutrient and demand
of crop at different growth stages to fertilizer, frequency of fertilizer application varies. Foreexample, large amount of fertilizer is applied to clay soil at longer interval than sand soil because
clay soil has capacity to retain nutrient for longer periods.
2. Quantity (rates) of fertilizer to be applied: - Quantity of fertilizer to be applied varies with soil
fertility, crop type (variety, growth stage), and type of fertilizer. If soil is low in one or more of
nutrients, application of that nutrient in a full dose (large quantity) to soil will increase the crop
yield. Therefore, appropriate quantity of fertilizer should be applied to crops.
3. Time of application of fertilizer: - The crops’ demand for nitrogen increases from the early growth
stage to the flowering stage, when their growth rate increases. Therefore, nitrogenous fertilizer
should be applied just before or during sowing the crop and the remaining is applied after planting.
The crop utilizes about 2/3 of their phosphoric and potash requirement during early growth period.
So those organic manures which supply potash and phosphate should be applied as basal dose just
before sowing. For example, partially rotten FYM should be applied to the soil three to four weeks
prior to sowing.
4. Methods of fertilizer placement: - Plant nutrients should be placed in the root zone, so that the
roots can assimilate them quickly. Depending on the plant space and types of fertilizer, fertilizer can
be applied in the form of: Band placement or row placement: - it is a way of applying the basal manure at the furrow
concentrated. It fit for any kinds of crops, soils (clay and sand soil)
Hill placement: - it is a way of applying basal manure at the holes concentrate. Fit for any kinds of
crops, soil, and climatic conditions.
Side dressing: - it is a way of applying fertilizer in between rows or around the growing crops, just
digging a hole or furrow, mainly for N fertilizers, solid or liquid.
Foliar application: - it is application of fertilizer through the leaves. Urea, well rotted urine and
many of the micronutrients are often used as foliar application.
5 Kinds of fertilizer to be applied: - Based on their formation and materials from which are produced,
fertilizer can be divided in to two groups. These are: - natural organic fertilizer and inorganic materials.
Based on quantities of organic matter and plant nutrient supplied, organic fertilizers can be categorized
into bulky organic manure (FYM, compost and green manure) and concentrated organic manure (oil
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cakes, urine, bone meal, and blood meal). Different kind of fertilizers is applied at different soils for
different crops.
3.2.1.3. Factors that determine level of fertilizer application
 Yield :- the higher yield the more the nutrients be taken
 Growing stage: o At seedling stage:- 10-12%
o At mid (jointing) stage:- 50-60%
o At later stage:-
50-60%
 Soil fertility: - Fertile soil needs light application, in the former stage and heavy in the later stage.
 Density: - Under high plant density, light application in former or before jointing and heavy in the
later from booting to heading.
 Rainfall: - in heavy rainfall areas, to some extent, nutrients of the soil will be leached such as N and
K, so the higher the rainfall the more the compensation.
 Types of crops: - different types of crops need different amount of fertilizers.
3.2.2. Applying irrigation
During application of irrigation for field crops you should have to know when, how often, how much of
water to be applied. There are no quick and easy methods for determining how much water plants need
and how often it should be applied. The frequency and amount of watering plants need depend on:
 Soil texture:- Sandy soils need more frequent (about twice as often) but lighter watering than clayey
soils since they can store only about half as much water per unit of depth.
 Root depth: - The shallower the root system of the soil, the more often watering is needed. Tiny
seedlings with roots only a few centimeters deep may need water 1-2 times a day on a very sandy soil
and once every 1-2 days on a clay or clay loam soil (depending on temperature, humidity, and wind).
As roots grow deeper, watering intervals can be spread out.
 Crop stage: - Young plants, with little top growth, require less water because they lose less by
transpiration than larger plants. Plants with succulent growth usually wilt sooner, because more of the
tissue is composed of water. And, plants with large thin leaves absorb and transpire water more
rapidly than those with small thick leaves.
 Crop type: - Crops themselves vary in the weekly and total amounts of water needed to grow them,
but there’s much variation among field crops. For example: - Millet is the most drought resistant
followed by sorghum and then peanuts and cowpeas.
 Temperature: - As temperature and/or wind increase and humidity decreases, water needs go up.
 Humidity and wind.
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 On the other hand, putting too much water on can cause drainage problems and leaching losses of
nutrients like nitrogen and also accentuate soil-borne fungal and bacterial diseases.
How Can You Tell When Plants Need Watering?
Wilting, leaf curling (or rolling), and, in some cases, color changes (maize turns bluish green, bean leaves
turn dark green) are the initial signs of moisture stress (lack of water). Yellowing and eventual browning
(“firing”) of the leaves, starting at the tips, are very advanced symptoms that occur after days of
continuous moisture stress. However, most of these symptoms can also be caused by anything else that
interferes with water uptake or water transport such as nematodes, soil insects, fungal and bacterial wilts,
stem borers, and even very high temperatures. N deficiency can cause yellowing too. Although young
plants can usually tolerate the initial symptoms (wilting, curling, color change) without any significant
yield drop, older plants (especially those that are flowering and fruiting) should not be allowed to reach
this stage or yields may be seriously affected. For example, if corn wilts for 2-4 days during pollination,
yields are usually reduced by 50%.
Remember, methods of irrigation application depend on types of crops and availability of irrigation
facilities.
3.2.3 Controlling pests
Pests are any form of plant or animal life, or any pathogenic agent, which is injurious or potentially
injurious to crop or crop products. Pests can be insect or weeds or pathogen or rodents.
3.2.3.1 Controlling weeds
3.2.3.1.1 Definition of weeds
A plant may be a weed to one person and a plant to another , or a weed in one place, but not in another ,
or a weed at one time of year and a valuable plant at another season. Weeds are therefore; defined in
various ways and the concept of weeds may vary over persons, locations and season or times.
 Weeds are plants which are grown out of place
 Weeds are the plants other than the crops sown
 Weeds are plants interfere with the objectives of human beings to cultivate specific types of crop.
3.2.3.1.2. Cropping density and competitive ability of crops plant
When cropping density is increased the crop is more competent with weeds. The crop plants may shade
the weeds, so greatly reduced the growth of weeds. It also reduces the competition of weeds for light,
nutrient and soil moisture. If the density is more than optimum, then there is adverse effect in the crops,
because no more competition for light and heat.
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3. 2.3.1.3. Weed competition and growth nature of field crops
Often the weeds are more aggressive than the crop being grown. In some cases the weeds emerge and use
up available nutrients before the crop plants are large enough to compete effectively. Some weeds require
more water for maximum growth than the crop in which the weeds are growing.
The competition depends on:  the environmental conditions,
 the root structure of weed, and
 the crop being grown
Broadleaf weeds growing with grass crops are partially adapted to compete for the sun light.
3.2.3.1.4. Methods of weed control
Weed can be controlled/eradicated by: - Control methods (cultural, biological, physical and chemical
methods) and prevention methods (using clean seeds, well decomposed organic matter, clear farm land,
cleaning irrigation channels, burning the straw in the field and plant quarantine law). Effective weed
control can be classified as physical, biological, cultural, chemical & IWM.
A) Physical (mechanical) methods of weed control
 Hand weeding :- it is physical removal or pulling of weeds by hand
 Weeding with hand held implements: - including, shovel, hoes and other hand tools. Weeding
with hand tools may bring many underground roots to the surface, where they may be killed as
they dried out by the sun or frozen.
 Mechanical tillage
 Mowing or chapping: - mowing or chopping cut off the weeds above the ground, providing them
from growing, maturing and producing viable seeds.
 Mulching the soil surface with a 5-10 cm layer of crop residues, dead weeds or grass can give
very effective weed control and provide a number of other benefits.
 Burning: when land is cleared by burning, standing annual weeds are killed along with weed
seeds very near the soil surface. However, burning will not kill weed seeds or reproductive
underground parts of perennial weeds if they are deeper than 4-5 cm.
 Flooding in rice crops
 Shading (the row crop principle): - arranging crops in rows facilitates hand weeding, but also
makes possible mechanical cultivation (weeding) with tractor or animal drawn equipment. In
addition, the rows permit the crop to exert better shade competition against the weeds.
B) Biological weed control
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It is host parasite relationship exists between organisms, that limits weed infestation several bio-agents
such as:  insects
 diseases organisms and
 herbivores
 even competitive plants
 fish other animals
C) Cultural methods
Weeding with hand tools is an effective method if sufficient labor is available. It is common, however,
for small farmers who rely on this method to fall behind in weeding and crop yields often suffer, it is
better to use some cultural weed control methods like:
 Tillage: - It is necessary in the case of weeds that spread by underground roots stocks. Existing
weeds are killed during land preparation
 Time of sowing: - Time of sowing affects the time to emergence and early seedling vigor. Maize,
soy bean and sorghum germinate and emerge in warm, moist soils.
 Use of crop rotation: - The life cycle of weeds common to fields can be ended before maturing
when the crop is changed to one with different growing season.
D) Chemicals weed control: - Some weed problems can best be controlled with the use of herbicides.
Where weeds are being controlled by hoeing or mechanical cultivation, their specific identification is
usually not important. Where chemical weed control is used, however, the farmer and extension worker
should have a good idea of which specific weeds are present since herbicides do not give broad-spectrum
control.
E) Integrated weed management/System approach/
It is where more than one method of weed control in a coordinate program is considered to most practical
approach to weed control. For example, for maize or sorghum:
 Time of sowing + fertilizer (N-fertilizer) higher dose for striga control + pre-emergence herbicide
hand weeding at 30-35 days.
 Pre-emergence herbicide + hand weeding at 25-30 days
 Intercropping with soybean (with maize) and cowpea (with sorghum) + pre-emergence herbicide.
3.2.3.2. Controlling insects and diseases
A) Insects
Insects: - are small animals which belong to Anthropoid phylum. Their body is divided into three
sections,
head, thorax and abdomen. Most adult insects have three pairs of legs and one or two pair of
functional wings. Major insects of field crops are like: - Stem borer, termite, cut worms, army worms,
white stems sawflies, aphids, African boll worm, sorghum shoot fly, green stink bug, pod borer, etc.
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B) Disease
Disease: - is an abnormal deviation in physiological, biochemical processed in plant. It results in
 Retardation of development of the plant.
 Reduction in quality and quantity.
 Expressed in the reactions of the plants.
Causal agent of plant diseases
Generally they are classified into two groups:Infectious diseases (biotic diseases):- are transmissible and they are caused by fungi, bacteria, nematodes,
etc
Non-infectious diseases: - are non-transmissible and they are caused by environmental factors like:
temperature effect, soil moisture, light, nutrient, mineral deficiency.
There are many diseases of field crops like: - rust, smut, bacteria blight, wilt, anthracnose, ergot, root rot,
stem rot, etc.
3.2.3.2.1. Control methods of diseases
Cultural methods
Cultural controls such as
 crop rotation
 intercropping
 burying crop residues
 timing the crop calendar to avoid certain insects and diseases,
 Controlling weeds and natural vegetation that harbor insects and diseases are all effective control
methods for some insects and diseases.
 In most cases, however, cultural controls need to be supplemented by other methods. Crop
varieties vary considerably in their resistance to certain insects and diseases. For example, maize
varieties whose ears have long, tight husks show good resistance to earworms and weevils; CIAT
found that some bean varieties were relatively unaffected by leafhopper damage during the wet
season, while others suffered yield losses up to 40%. Screening for insect and disease resistance is
an important part of crop breeding programs
Organic materials
"Organic" control refers to non-chemical methods in general, including the application of homemade
"natural" sprays made from garlic, pepper, onions, soap, salt, etc. and the use of materials like beer to kill
slugs and wood ashes to deter cutworms and other insects. Some of these "alternative" insecticides are
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slightly too fairly effective on small areas like home gardens and where insect populations are relatively
low.
Mechanical control
In greenhouse, soil sterilized by heat helps control some plant diseases. Use of hot water is also effective
in producing clean seed and planting materials. Seed and vegetative propagation materials (such as roots,
bulbs, corms, and tubers) may be treated before planting to control some fungal, bacterial, and viral
diseases. In greenhouses and other enclosed growing areas, as well as in areas where food and feed are
stored, you may be able to control temperature and humidity to keep pathogens from building up rapidly
enough to cause damage.
Sanitation
Sanitation practices help to prevent and suppress some plant diseases by removing the pathogens
themselves or their sources of food and shelter. Disinfecting equipment and tools
Integrated pest management
Each control measure is not always effective when used alone. Therefore, there is a general agreement
among scientists of any two or more control measure that is compatible to the farming system and each
other are advisable.
3.3.2.2. Control methods of Rodents and birds
Birds: - Quelea is the birds those move together and difficult to control. Spray chemical (fenthion mixed
with diesoline) early in the morning when they are in their nest is very suitable. As many birds are insect
feeder, they give more benefit than harm. Control methods of birds are:
Scaring
Planting non-attractive cultivar
Attach at nest and roofing areas
Using chemicals
Rodents are animal such as rat, mole, monkey, pigs, etc
Rodents can be controlled by the use of
 Closing holes leading to stores by using
wire mesh.
 Digging big holes ,
 Scaring, etc
 Using fencing
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LO4: - Complete establishment and maintenance operations
4.1. Cleaning tools and equipments
Tools and equipment should be cleaned and sterilized according to the manufacturer’s specifications,
enterprise procedures and regulations. This is used to increases life span of tools and equipments and
avoids scarcity of tools and equipments at critical periods. Always before storing of tools and equipments
cleaning is a must.
4.2. Implementing waste disposal operations
After completion of all field establishment activities all containers, leftover fluids, waste and debris
should be disposed safely and appropriately. Waste materials which may be toxic to human beings or
pollutants environmental conditions should be properly disposed to minimize hazards.
4.3. Completing all work place records
All required work place records should be completed accurately and promptly in accordance with
enterprise requirements. Recording and documenting your work activities in an area serves you for
several purposes simultaneously. It helps you in evaluating and learning from past field establishment
efforts. It helps you to organize your own work for the future and allows you more closely monitor your
activities.
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