Maize Production manual-allpractices.ppt

Maize production guide.

1. CHITIPA DISTRICT AGRICULTURE
DEVELOPMENT OFFICE
CROPS DEPARTMENT
NOVEMBER, 2020

2. MAIZE PRODUCTION
2

3. Introduction
Maize (Zea mays L.) is the most important grain crop in
Malawi
It is the main staple food crop. As such, farmers are
encouraged to store enough maize for their family
requirements until the next harvest and sell only surplus.
It is produced throughout the country under diverse
environments; under rainfed, irrigated or residual
moisture (dimba) conditions
Successful maize production depends on the correct
application of production inputs that will sustain the
environment as well as agricultural production
These inputs include adapted cultivars, plant population,
soil tillage, fertilization, weed, insect and disease control,
harvesting, marketing and financial resources.
3

4. Introduction (cont’d)
In developed countries, maize is consumed mainly as
second-cycle produce, in the form of meat, eggs and
dairy products.
 In developing countries, maize is consumed directly and
serves as a major staple diet
However, in a processed form, maize has a number of
products like:
i) fuel (ethanol)and starch
ii)Starch is further converted into
products such as sorbitol, dextrine, sorbic and lactic acid,
iii) appears in household items such as beer, ice cream,
syrup,
iv) is also processed into shoe polish, glue, fireworks, ink,
batteries, mustard, cosmetics, aspirin and paint
4

5. Origin of Maize
Maize(Zea maysL.)originated from Mexico and Central
America, got spread to Europe, Asia and then to Africa
Cultivated maize is a fully domesticated plant that is
unable to survive without human husbandry.
An annual teosinte (Zea mexicana)is an ancestor and
closest relative of maize (Zea mays).
Like Zea mays teosinte has10 pairs of chromosomes
which are cytogenetically similar to those of Zea Mays
and the plants hybridize freely, producing fertile progeny.
The English speaking world refers to Zea mays as maize
while the largest producer, USA, refers to it as corn.
5

6. Classification of Maize
Maize belongs to the family: Graminae, genus: Zea,
Species: mays, and sub- species: mays
Sub species of maize
Flour corn- Z. mays L. spp. mays Amylacea group
Pop corn- Z. mays L. spp. mays Everta group
Dent corn- Z. mays L. spp. mays Indentata group
Flint corn- Z. mays L. Spp. mays Indurata group
6

7. Grain Texture
This refers to hardiness (flintiness) or softness (dentiness) of
the kernel
A scale of 1-5 is used to estimate, where 1 = very flint (no
depression at the top of the kernel), 3 = intermediate, 5 =
very dent (the kernel has a depression)
 Flint kernels have higher percentage of amylopectin
starch formed by branched chain of glucose molecules
of high molecular weight. Branching reinforces the
caryopsis
Dent (soft) kernels have relatively higher percentage of
amylose starch formed by straight chain of glucose
molecules
7

8. Grain Texture
Regular corn contains, according to International starch
Institute, 2001 :
72-76% amylopectin
24-28% amylose
Flintiness is an indication of good poundability, a trait
preferred in Malawi
Also the flint grains are hard to penetrate by storage
pests
The poundability (kernel extraction-mphale) of :
local maize is 70%
MH18 is 68%
8

9. Normal Maize Grain Protein
The normal maize grain protein consists of four fractions:
a) Albumins ( water soluble) 3%
b) Globulins (salt soluble) 3%
c) Prolamines or Zein (alcohol soluble) 60%
d) Glutelines (alkali soluble) 34 %
Source: Osborne, 1997.
Note: Globulins and Glutelines are quite rich in their lysine
and tryptophan content (>2g/100g protein) as
compared to the very low levels of them in Prolamine
fraction (Zein) 0.01% (Vasal, 2002).
9

10. Quality Protein Maize (QPM)
QPM has 60-100% more lysine and tryptophan content
relative to normal maize.
Remember:
Normal and Quality Protein Maize have on average
equal protein content (8-12%); it is the Protein Quality
that differs between them.
10

11. Environmental Requirements
Maize needs 450 - 600 mm of water per season, which is
mainly acquired from the soil moisture reserves.
About 15 kg of grain are produced for each millimetre of
water consumed.
At maturity, each plant will have consumed 250 litres of
water
 The total leaf area at maturity may exceed one square
metre per plant.
11

12. Environmental Requirements
The assimilation of nitrogen, phosphorus and potassium
reaches a peak during flowering.
At maturity the total nutrient uptake of a single maize
plant is :
8.7 g of nitrogen
5.1 g of phosphorus, and
4.0 g of potassium.
Each ton of grain produced removes from the soil:
15.0 -18.0 kg of nitrogen,
2.5 - 3.0 kg of phosphorus
3.0 – 4.0 kg of
potassium
12

13. Environmental Requirements
No other crop utilises sunlight more effectively than maize
Its yield per ha is the highest of all grain crops
The number of kernel rows may vary between 4 and 40,
depending on the variety; but most varieties in Malawi
have between 8 and 14 rows
The kernel rows are always an even number ie 8, 10, 12,
14, 16
Up to1000 kernels may be produced by a single plant
Each tassel produces some 25 000 000 pollen grains, i. e.
25 000 grains for each kernel.
As a result, up to 40 % of the tassels in a plant may be lost
without affecting pollination, other factors remaining
optimal
13

14. Understanding Maize Behaviour
Morphology, Growth and Development
14

15. Understanding Maize Behaviour
Morphology, Growth and Development
The Root System
If root growth is not restricted, the root system of a
mature plant extends approximately 1.5 – 2.0m laterally
and downwards
 The permanent root system has adventitious and prop
roots.
Adventitious roots develop in a crown of roots from
nodes below the soil surface
 Normally 4 - 6 adventitious roots are formed per band.
After tasselling, prop roots develop into bands from the
first two to three aerial nodes
15

16. Understanding Maize Behaviour
Morphology, Growth and Development
The Root System
These roots are comparatively thick, pigmented and
covered with a waxy substance.
Prop roots have the dual function of providing support to
the plant and taking up nutrients.
Numerous root hairs occur on young plants
 Root hairs increase root surface area that is exposed to
the soil, and play an important role in absorption of
water and nutrients.
16

17. Understanding Maize Behaviour
Morphology, Growth and Development
The Leaves
The 8 - 20 leaves that may form are arranged spirally on
the stem
They occur alternately in two opposite rows on the stem
 The maize leaf is a typical grass leaf and consists of a
sheath, ligules, auricles and a blade
 The leaf blade is long, narrow, undulating and tapers
towards the tip and is glabrous to hairy
 The leaf is supported by a prominent mid-rib along its
entire length
17

18. Understanding Maize Behaviour
Morphology, Growth and Development
The Leaves
Stomata occur in rows along the entire of the leaf
surface
 More stomata occur on the underside of the leaf than
on the upper surface
During moist conditions, these cells rapidly absorb water,
become turgid and unfold the leaf
 During warm, dry weather, the cells quickly lose their
turgor with the result that leaves curl inwards exposing a
smaller leaf surface to evaporation.
18

19. Understanding Maize Behaviour
Morphology, Growth and Development
The Stem
The maize stem varies in height from less than 0.6 m in
some genotypes to more than 5.0 m (in extreme cases)
in others
 The stem is cylindrical, solid and is clearly divided into
nodes and internodes
 It may have 8 - 21 internodes
 The internodes directly below the first four leaves do not
lengthen, whereas those below the sixth, seventh and
eighth leaves lengthen to approximately 25, 50 and 90
mm, respectively.
Tillers may develop from nodes below the soil surface.
19

20. Understanding Maize Behaviour
Morphology, Growth and Development
The Stem
The lateral shoot bearing the main ear develops more or
less from the bud on the eighth node above the soil
surface
The five or six buds directly below the bud give rise to
rudimentary lateral shoots of which one or two develop
to produce ears.
20

21. Understanding Maize Behaviour
Morphology, Growth and Development
The Inflorescence
Male and female flowers are borne on the same plant as
separate inflorescences
Male flowers are borne in the tassel and female flowers
on the ear

21

22. Understanding Maize Behaviour
Morphology, Growth and Development
The Ear
The maize ear (the female inflorescence) terminates one
or more lateral branches, usually halfway up the stem.
Bracts enclose the ear. The silk of the flowers at the
bottom appear first and thereafter those on the upper
part of the ear.
It remains receptive to pollen for approximately 3 weeks
but after the tenth day, receptivity decreases.
22

23. Understanding Maize Behaviour
Morphology, Growth and Development
The Maize Kernel
The maize kernel consists of an endosperm, embryo, a
pericarp and tip cap (Fig. 1)
 The endosperm contains the main carbohydrates
 The embryo contains the parts that give rise to the next
generation
 The pericarp and tip cap enclose the entire kernel.
23

24. Understanding Maize Behaviour
Morphology, Growth and Development
The Maize Kernel
The endosperm contains approximately
80 % of the carbohydrates
20 % of the fat and
25 % of the minerals
The embryo contains about
80 % of the fat
75 % of the minerals and
20 % of the protein found in the
kernel.
24

25. Understanding Maize Behaviour
Morphology, Growth and Development
The Maize Kernel
The starch part of the kernel is used in foods and many
other products such as
- adhesives
- clothing
- pharmaceutical tablets
- in paper production
 The starch can be converted into sweeteners and used
in products such as:
- soft drinks
- sweets
- bakery products
- jams
to name but a few.
25

26. Understanding Maize Behaviour
Morphology, Growth and Development
The Maize Kernel
The oil from the embryo is used in cooking oils, margarine
and salad dressings.
The protein, hulls and soluble part of the maize kernel are
used in animal and poultry feed.
26

27. Understanding Maize Behaviour
Morphology, Growth and Development
Chemical Composition of the Maize Kernel
Kernels can be of the dent or flint (round) types
27
Component %
Carbohydrates 84.0
Protein 10.9
Fat 4.5
Minerals 1.3

28. Understanding Maize Behaviour
Stages of Maize Development
Stages of maize development are broadly categorised
into Vegetative (V) and Reproductive (R) stages.
Subdivisions of the V stages are designated numerically
as V1, V2, V3, etc, through V (n) where n represents the
last leaf stage before VT for the specific hybrid under
consideration.
The first and last v stages are designated as
VE (emergency and VT (tasselling)
The (n) will fluctuate with hybrid and environmental
differences
28

29. Understanding Maize Behaviour
Stages of Maize Development
The 6 subdivisions of the reproductive stages are
designated numerically with their common names.
 Each leaf stage is defined according to the upper most
leaf whose leaf collar is visible.
The first part of the collar that is visible is the back of
which appears as a discoloured line between the leaf
blade and leaf sheath
29

30. Understanding Maize Behaviour
Stages of Maize Development
Different growth stages are numbered 0 to 10.
Growth stage 0 lasts from planting of the seed up to
when the seedling is just visible above the soil surface.
Growth stage 10 is reached when the plant is biologically
mature
30

31. Understanding Maize Behaviour
Germination and Emergence (VE)
Under adequate field conditions, the planted maize
seed absorbs water (imbibition) and begins growth
 The radical is first to begin elongation from the swollen
kernel followed by the coleoptile with the enclosed
plumule(embryonic plant) and then the three to four
lateral roots.
VE (emergence) is finally attained by rapid mesocotyl
elongation which pushes the growing coleoptile to the
soil surface.
Under warm, moist conditions plant emergence will
occur within 4-5 days after planting, but under cool or
dry conditions 2 weeks or longer may be required.
31

32. Understanding Maize Behaviour
Stages of Maize Development32
Growth
Stage
Period Description of events
0 Planting to
Seed
Emergence
-During germination, the growth point and the
entire stem are about 25 to 40 mm below the soil
surface.
-Under warm, moist conditions seedlings emerge
after about 4 - 5 days, but under cool
or dry conditions this may take two weeks or
longer.
-The optimum temperature range for germination is
between 20 and 30 ºC
-Optimum moisture content of the soil should be
approximately 60 % of soil capacity.
1 4 leaves
completely
unfolded
-The maximum number of leaves and lateral shoots
is predetermined
-A new leaf unfolds more or less every third day.
-The growth point at this stage is still below the soil
surface

33. Understanding Maize Behaviour
Stages of Maize Development33
Growth
Stage
Period Description of events
1 4 leaves
completely
unfolded
-Aerial parts are limited to the leaf sheath and
blades.
-Initiation of tasselling also occurs at this stage.
2 8 leaves
completely
unfolded
-During this period, leaf area increases five to 10
times
-Stem mass increases 50 to 100 times
-Ear initiation has already commenced.
-Tillers begin to develop from nodes below the soil
surface.
-The growth point at this stage is approximately 5.0 to
7.5 cm above the soil surface

34. Understanding Maize Behaviour
Stages of Maize Development34
Growth
Stage
Period Description of events
3 12 leaves
completely
unfolded
-The tassel in the growth point begins to develop
rapidly.
-Lateral shoots bearing cobs develop rapidly from
the 6
th
– 8
th
nodes above the soil surface
-The potential number of seed buds of the ear has
already been determined.
4 16 leaves
completely
unfolded
-The stem lengthens rapidly
-The tassel is almost fully developed.
-Silks begin to develop and lengthen from the base
of the upper ear.

35. Understanding Maize Behaviour
Stages of Maize Development35
Growth
Stage
Period Description of events
5 Silk
appearanc
e to Pollen
shedding
-All leaves are completely unfolded
-The tassel has been visible for two to three days.
- Each silk is attached to a potential kernel on
the cob
-The lateral shoot bearing the main ear as
well as bracts has almost reached maturity.
-At this point demand for nutrients and water is high. -
It takes 2-3 days for all silks on a single ear to be
exposed and pollinated.
- The silks will grow from 2.5-3.8cm each day and will
continue to elongate until they are fertilized
- Environmental stresses like moisture and heat
stress cause poor pollination and poor seed set
- Stress will result in an ear with barren
tip.
- Nitrogen and phosphorus uptake is rapid at this
stage.
- Potassium uptake is essentially complete.

36. Understanding Maize Behaviour
Stages of Maize Development36
Growth
Stage
Period Description of events
6 Green
mealie
stage
-The ear, lateral shoot and bracts are fully
developed
-Starch begins to accumulate in the endosperm
-This is also R2 stage (ie 10 – 14 days after silking)
7 Soft dough
stage
-Grain mass continues to increase
-Sugars are converted into starch.
-Milky grain stage R3 (occurs 18-22 days after
silking)
8 Hard dough
stage
-Sugars in the kernel disappear rapidly.
-Starch accumulates in the crown of the kernel and
extends downwards.
R4 stage occurring some 24-28 days after
silking
9 Physiologic
al maturity
-When the kernel has reached its maximum dry
mass, a layer of black cells develops at the kernel
base.
-Grains are physiologically mature
-Only the moisture content must be reduced.

37. Understanding Maize Behaviour
Stages of Maize Development37
Growth
Stage
Period Description of events
9 Physiologic
al maturity
-The R5 stage occurs 35 – 42 days after silking
-Kernels have 55% moisture content at the beginning
of R5
-Stress will reduce yield by reducing kernel weight not
kernel number
-Frost may stop dry matter accumulation and cause
premature black layer formation.
-Phsiological maturity (R6)occurs approximately 55-65
days after silking
-All kernels have reached their maximum dry
matter accumulation now

38. Understanding Maize Behaviour
Stages of Maize Development38
Growth
Stage
Period Description of events
10 Drying of
kernels
(biological
maturity)
-Although grains have reached physiological
maturity, they must dry out before reaching
biological maturity.
-Under favourable conditions, drying takes place at
approximately 5 % per week up to the 20 % level,
after which there is a slowdown
-The grain is not yet ready for safe storage which
requires 13-15% MC level for shelled maize
-The rate of field drying after R6 depends
on the hybrid and the environment

39. 39
A maize plant determines number of kernels at about 19 days from planting closer to
knee-high and finishes 10 to 14 days prior to silk emergence.

40. Climatic Requirement
Temperature
Maize is a warm weather crop; performing best at
temperatures of between 20 – 30 degrees celcius
Although the minimum temperature for germination is 10
ºC, germination will be faster and less variable at soil
temperatures of 16 to 18 ºC.
At 20 ºC, maize should emerge within 5 – 6 days
Frost can damage maize at all growth stages
A frost-free period of 120 to 140 days is required to
prevent damage
40

41. Climatic Requirement
Temperature
While the growth point is below the soil surface, new
leaves will form and frost damage will not be too serious.
Leaves of mature plants are easily damaged by frost and
grain filling can be adversely affected.
41

42. Climatic Requirement
Water
Approximately 10 to 16 kg of grain are produced for
every mm of water used.
At maturity, each plant will have used 250 litres of water
in the absence of moisture stress.
42

43. Soil Requirement
The most suitable soil for maize is one which is
deep
fertile
well drained
Well aerated
has the right soil pH
43

44. Soil Requirement
Although large-scale maize production takes place on
soils with a clay content of less than10 % (sandy soils) or in
excess of 30 % (clay and clay-loam soils), the texture
classes between10 and 30 % have air and moisture
regimes that are optimal for healthy maize production.
44

45. MAIZE PRODUCTION IN MALAWI
45

46. Maize is grown throughout the country under rainfed,
irrigated or residual moisture (dimba) conditions.
It is the main staple food crop. As such, farmers are
encouraged to store enough maize for their family
requirements until the next harvest and sell only surplus.
At present,average yields range from:
2,000 - 3,000 kg/ha for hybrids,
1,400 - 2,400 kg/ha for OPVs
880 - 1,300 kg/ha for unimproved maize cultivars
However, yields of more than10,000 kg/ha for hybrids
and 5,000 kg/ha for OPVs can be attained with good
management.
46

47. Classification of areas for maize production
Low altitude areas
Are less than 600 m above sea level (masl).
These areas are characterized by high summer
temperatures of about 300C or more
Relatively flat
Have a generally short rainy season of between 3 to 4
months long
 The average rainfall is between 700 to 800 mm per
annum
These areas are also called marginal maize growing
areas associated, with erratic rains and frequent
droughts / dry spells
47

48. Classification of areas for maize production
Low altitude areas
Examples are
a)the Shire Valley
b) Phalombe Plain
c) Lakeshore Plain
d)Upper Shire Valley from Kapichira Falls to
Mangochi e)Nkhamanga plain.
Short duration maturing varieties are best suited for these
areas.
48

49. Classification of areas for maize production
Medium altitude areas
These are main maize growing areas which comprise
about 60% of the total cultivated area
Altitude ranges from 600 to 1,300masl.
These areas are characterised by moderate temperatures
and a fairly long rainy season of between 4 to 5 months
Have an average rainfall of about 875mm per annum.
Examples of such areas include
a) Lilongwe- Kasungu plain
b) Upper South Rukulu Valley
c)Shire Highlands
d) Chitipa
plain.
49

50. Classification of areas for maize production
High altitude areas
These are areas above 1,300 masl
Are characterized by cool temperatures and overcast
conditions
 Maize takes long to mature because of low
temperatures.
Examples of such areas are
a) Viphya and Nyika Plateaus
b) Kirk Range
c) Dedza Hills
d) Dowa Hills
e) Misuku hills.
50

51. Improving Yields
In order to achieve the potential yields the following
husbandry practices are recommended:-
1.0 Early planting :
i) Prepare gardens early – ploughing March to early May
ii) Make ridges – by Oct
iii) Apply well decomposed OM by end mid Nov
Plant with the first effective planting rains
(ie rains that have reached at least 50.0 mm falling
within 3 days, and wetting a soil depth of up to 15 cm).
This moisture is enough to sustain maize plant growth up
to the next 14 days even without further rains
Maize can also be dry planted 1 to 2 weeks before onset
of rains; when indicators of rains coming soon within 1 – 2
weeks time are eminent
51

52. Improving Yields
1.0 Early planting :

1 to 2 weeks delay in planting may cause up to 25% yield loss
Yield loss due to late planting of hybrid varieties is much more
than it is due to rotting that may arise as a result of prolonged
rains
2.0 Recommended plant population :

Optimum plant population is achieved by proper ridge and
plant spacing, and number of plants per station
This is achieved by planting maize at : 75 cm
x 75 cm x 3 plants / station or 75 cm x
25 cm x 1 plant / station; giving a plant population of 53,333
plants per hectare
52

53. Improving Yields
2.0 Recommended plant population :

Other alternative spacings are :
90 cm x 75 cm x 3 plants / station or
75 cm x 60 cm x 2 plants / station or
75 cm x 30 cm x 1 plant / station (giving a
plant population of 44,444 plants per hectare)
Gaps and stations with less number of seedlings should
be filled immediately after crop emergence to ensure
correct plant population and an even plant stand
53

54. Improving Yields
3.0 Use of improved and good quality seed :


a) Hybrid Maize:
Seed for hybrid maize varieties should be bought every
season
The recommended hybrid maize varieties currently in use
include the following:
54

55. Improving Yields
3.0 Use of improved and good quality seed :


55
Agro-ecological ZoneSuitable VarietyDays to
Maturity
Potential Yield (ie
kg/ha)
Low altitude SC 513 130 6,000 kg
Low altitude
Low to medium SC 403 120 – 130 5,000 kg
Low to medium DKC 8033 120 – 130 8,000 kg
Low to medium MH 18 120 – 130 6,000 kg
Low to medium Pan 4M-19 120 – 130 6,000 kg
Medium altitude PHB 30G97 130 - 140 9,000- 10,000 kg
Medium altitude PAN 57 130 - 140 7,000 kg
Medium altitude PAN 63 130 - 140 7,000 kg

56. Improving Yields
3.0 Use of improved and good quality seed :


56
Agro-ecological Zone Suitable VarietyDays to
Maturity
Potential Yield
(ie kg/ha)
Medium altitude PHB 309H83 130 - 140 7,000 kg
DKC 80-73 130 - 140 8,000 kg
Medium – High altitudeDKC 90-89 130 - 140 9.000 kg
Medium – High altitudeSC 627 130 - 140 8,000 kg
Medium – High altitudePAN 57 130 - 140 8,000 kg
Medium – High altitudePAN 63 130 - 140 8,000 kg
Medium – High altitudePAN 77 130 - 140 8,000 kg
Medium – High altitudeSC 709 140 - 150 13,000 kg
Medium – High altitudeSC 715 140 - 160 11,000 kg
Medium – High altitudeSC 717 140 - 160 13,000 kg
Medium – High altitudeSC 719 140 - 160 12,000 kg

57. Improving Yields
3.0 Use of improved and good quality seed :


57
Agro-ecological Zone Suitable VarietyDays to
Maturity
Potential Yield
(ie kg/ha)
Medium altitude SC 727 130 - 140 15,000 kg
Medium – High altitudePHB 30G19 140 - 160 7,000 kg
Medium – High altitudeDKC 8053 130 - 140 10.000 kg
Medium – High altitudeSC 533 120 - 130 6,000 kg

58. Improving Yields
3.0 Use of improved and good quality seed :


b) Open Pollinated Maize Varieties (OPVs):
Most OPVs range from semi flint to flint and therefore
have good poundability and storage characteristics
Certified seed can be purchased every year or seed
from selected cobs from the centre of the garden can
be used for 3 successive seasons
After 3 seasons, new fresh seed should be acquired
58

59. Improving Yields
3.0 Use of improved and good quality seed :


59
Agro-ecological
Zone
Suitable VarietyDays to
Maturity
Potential Yield (ie
kg/ha)
Low altitude ZM 309 90 - 120 4,500 kg
Low altitude ZM 523 110 - 120 6,000 kg
Low to medium Chitedze 5 110 – 125 6,000 kg
Low to medium QPM (VPO 5195) 110 – 120 5,000 kg
Low to medium QPM (Thanzi) 120 – 130 6,500 kg
Medium ZM 623 130 – 140 7,000 kg
Medium ZM 721 130 – 140 8,000 kg
Medium AFRIC 1 130 – 140 8,000 kg

60. Improving Yields
3.0 Use of Organic Manure:

Manure improves soil structure as well as supplying nutrients
to plants
 Manure should be applied not less than a month before
planting maize and the recommended rate is 12.5 tons per
hectare
As a guide this can be achieved by using a 20 litre tin of
manure applied every 8 metres (8 steps) along the furrow
 Where manure is not adequate farmers should apply 1
double handful per planting station and mix with soil
before planting
Encourage farmers to make compost manure from
household decomposable refuse and crop residues
60

61. Improving Yields
3.0 Use of Chemical fertilizers:

Farmers are strongly advised to base fertilizer application
on soil test results
 Two area specific fertilizer recommendations are given
for one area depending on whether is produced for
home use or for sale
Apply fertilizers as follows:
Apply 100 kg of NPK (23:21:0+4S or 23:10:5 +6S+1.0Zn) and
150 kg of Urea per hectare as follows:
i) Mix NPK with Urea in the ratio 2 : 1 (for any
container used, be it bucket, basin, pot, etc)
ii) Use all the 100 kg of NPK plus 50 kg of
Urea per hectare for basal dressing
61

62. Improving Yields
3.0 Use of Chemical fertilizers:

iii)Basal fertilizers should be applied at planting or soon
after seedling emergence (ie at about 5 – 7 days)
iv)The fertilizer should best be applied in dollops
made 7cm -10 cm away from the planting station and 10
cm deep; for maize planted at 75 cm or 60 cm or 50 cm
apart in a row. For maize planted at 25 cm apart, fertilizer
is dolloped half-way in between 2 planting stations in a
row
v)Use cup 5, ¾ full, or a fanta / coke bottle top
(heaped) without a plastic liner inside per dollop
vii)Follow up with 100 kg of Urea
at the same distance and depth using a coke bottle top
(level full) with a liner inside
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63. Improving Yields
3.0 Use of Chemical fertilizers:

Apply fertilizers as follows:
Where CAN is used instead of Urea, apply 250 kg/ha:
viii) Mix NPK with CAN in the ratio 2 :
1 (for any container used, be it bucket, basin, pot, etc)
ix) Use all the 100 kg of NPK plus
50 kg of CAN per hectare for basal dressing
x)Follow up with 200 kg of Urea at the
same distance and depth using 2 coke bottle tops (level
full) with a liner inside per dollop
Apply top dressing fertilizers not later than 4 weeks after
planting
63

64. Improving Yields
3.0 Use of Chemical fertilizers:

The recommendations are based on the available
fertilizers like NPK and Urea (46 %N) but CAN can be used
if Urea is not available
*35:10:0+2S=1 bag of NPK and 1 bag of Urea/ha (50 kg
bags)
*69:21:0+4S = 2 bags of NPK and 2 bags of Urea/ha (50
kg bags)
*92:21:0+4S = 2 bags of NPK and 3 bags of Urea ( 50kg
bags)
64

65. Improving Yields
3.0 Lime Application:

An application of 2,000kg/ha lime to maize grown on
acidic soils is effective at increasing grain and dry matter
yields.
Acid soils are mainly in areas characterized by high total
rainfall (>900 mm per year) and low soil pH levels (<5.5),
such as on vast areas on Mulanje, Dedza, Misuku and
Viphya plateaus.
Agricultural lime needs to be applied on newly prepared
ridges, which have been split in the middle
 The lime is incorporated into the ridge and maize is
planted at the recommended plant density
65

66. Improving Yields
3.0 Lime Application:

The best source of local agricultural lime (lupanya) in
Malawi is near Chuzi in Chikhwawa district and Uliwa
(Chilumba) in Karonga district
 Other lime deposits are found in many parts of Malawi
especially in Ntcheu and Balaka districts.
66

67. Improving Yields
3.0 Pest Control:

Maize pests are categorized into weeds and insect pests.
Notifiable pests should be reported to the nearest
agricultural office immediately they are noticed
 Any pest outbreaks should be controlled to prevent
damage and spread to other areas.
67

68. Pest Control
Pest Description
Weeds *Maize suffers most from weed competition during the first six
weeks after germination.
*The crop should be weed-free during this period.
*The smaller the crop the less it is able to survive competition
*At least two weedings are necessary for effective weed control
•Herbicides can also be used for weed control.
*There are pre- and post-emergence herbicides
*Pre- emergence herbicides are direct into the soil; hence the
soil must be wet enough for the chemicals to be effective
*Post-emergence herbicides are directed to the weeds; hence
need to be applied when the weather is dry
*A post-emergence herbicide is the one that may be applied
when the targeted crop has emerged
*All herbicides have labels indicating application rates and type
of weeds they control.
68

69. Pest Control
Pest Description
Weeds *It is important to check the labels as application rates can
change even with the same product depending on
concentration and soil type
•Application rates of some of the herbicides in common use:
•Roundup – 5.0 litres / ha applied direct onto weeds that have
already emerged, but before planting a crop (ie Post-
emergence herbicide) - Glyphosate
•Bullet – 5.0 litres / ha applied in the soil before weed seeds and
planted crop seeds germinate and emerge (ie Pre- emergence
herbicide)
•Harness – 1.0 litres / ha applied in the soil before weed seeds
and planted crop seeds germinate and emerge (ie Pre-
emergence herbicide) - Acetochlor
*Dual Magnum – 2.2 litres / ha applied in the soil before weed
seeds and planted crop seeds germinate and emerge (ie Pre-
emergence herbicide)
69

70. Pest Control
Pest Description
Common
Weeds of
Economic
Importance
a) Witchweed
*Serious problem in areas where maize is monocropped with
poor management.
Management Options
i)Adequate manuring and fertilizer application will help the
crop withstand the effect of witchweed.
ii)Uprooting the weed before it flowers will help to reduce its
population in succeeding seasons.
iii)Crop rotation with catch crops such as sunflower and
cotton should be practised as where land permits
70

71. Pest Control
Pest Description
Witchweed
*Serious problem in areas where maize is monocropped with
poor management.
Management Options
i)Adequate manuring and fertilizer application will help the crop
withstand the effect of witchweed.
ii)Uprooting the weed before it flowers will help to reduce its
population in succeeding seasons.
iii)Crop rotation with catch crops such as sunflower and cotton
should be practised as where land permits
Other weeds of economic importance include :
i) Wild finger millet (dulu) – Eleusine indica
ii)Kapinga - Cynodon dactylon
iii)Black jack (Chisoso) - Bidens pilosa
iv)Amaranthus (Berekete)
v) Ndau - Cyperus rotundus
71

72. Pest Control
Pest Description
Other weeds of economic importance include :
i) Wild finger millet (dulu) – Eleusine indica
ii)Kapinga - Cynodon dactylon
iii)Black jack (Chisoso) - Bidens pilosa
iv)Amaranthus (Berekete)
v) Ndau - Cyperus
rotundus
Management Options:
i) Frequent weeding
ii) Use of systemic herbicides such as
glyphosate which kill under ground root system.
72

73. Pest Control
Pest Description
Important
Insect Pests
i) African
Armyworm –
(Spodoptera
exempta)
*Serious notifiable pest of cereals which is very destructive
particularly to maize, rice, wheat, sorghum, millets and
pastures.
*Armyworm is an endemic pest and the attack may be
sudden.
*Quite often outbreaks occur soon after the first rains.
*The caterpillars occur in large numbers, march in one
direction, aggressively feeding on all grasses in their way.
*They may also occur as scattered populations which may
lead to larger outbreaks later.
*They prefer young tender plants which they chew to the
ground while old ones are left as bare stalks with midribs
only.
*Early detection and reporting of the pest is important for
effective control to minimize damage.
73

74. Pest Control
Pest Description
Important
Insect Pests
i) African
Armyworm –
(Spodoptera
exempta)
Management Options
*Set up sex pheromone traps for forecasting possible
armyworm outbreaks.
*A rise in moth catches in these traps is an indication of
potential outbreaks.
*Extension staff should, therefore, advise farmers to inspect
their fields regularly
*Apply synthetic pesticides
i) Carbaryl (Sevin) 85WP – 85g mixed in 14 litres, and
1 litre of water for knapsack and ULV sprayers respectively
ii) Fenvalerate (Sumicidin) 20EC – 13 mls in 14 litres,
and in 1 litre of water for knapsack and ULV sprayer iii)
Fenitrothion (Sumithion) 50EC – 136 mls in 14 litres of water
* Promote use of natural enemies
74

75. Pest Control
Pest Description
Important Insect
Pests
ii) Red locusts –
(Nomadacris
septemfasciata)
*A notifiable pest and potentially the most destructive in
Malawi
*Can cause extension damage within a short period of
time
•Leaves are eaten from the margins inwards
•In Malawi, breeding places include: Lake Chilwa plains,
Ndindi and Vwaza Marshes, Mpatsanjoka dambo,
Kuserikumvenji Estate
•The eggs are laid in the wet season – Nov. to April, and
hatch after 30 days
Management Options
•Frequent monitoring to detect unusual population build
up
•Immediate reporting of any swarms spotted to the agric.
or any govt. office
•Use of chemical sprays
75

76. Pest Control
Pest Description
Important Insect
Pests
ii) Large short-
horned
grasshopper – ()
•Farmers sometimes mistake it for Red locust
Management Options
•As for Red locusts
76

77. Pest Control
Pest Description
Important
Insect Pests
iii) Maize Stalk
borer –
(Busseola fusca,
Chilo partellus)
•The two – Busseola fusca and Chilo partellus – are the
most import stalk borer species that attack maize
•Busseola fusca is commonly found in high altitude areas of
above 800 m.a.s.l causing considerable damage there
and to the late planted crop
*Chilo partellus is most important in low altitude areas
below 800m above sea level.
*The larvae hatch from eggs laid in the leaf sheath
feeding on the folded leaves as they burrow
into the main stem.
*Pupae overwinter inside the stalks
*Also attacks sorghum and sugarcane
*Some wild plants are alternate hosts
Management Options
*Feed infested crop residues (stalks) to livestock or bury
them
77