MILLET
OYEWOLE, C.I.
Department of Crop Production,
Faculty of Agriculture, Kogi State
University,
P.M.B. 1008, Anyigba, Kogi State,
Nigeria
Plate 1: Millet Growing Areas
in the World
Introduction
Millets
include
five
genera,
Panicum,
Setaria,
Echinochloa,
Pennisetum, and Paspalum, all of the tribe Paniceae; one genus,
Eleusine, in the tribe Chlorideae; and one genus, Eragrostis, in the
tribe Festuceae.
The most important cultivated species of millet are foxtail (Setaria
italica), pearl or cattail millet (Pennisetum glaucum), proso (Panicum
miliaceum), Japanese barnyard millet (Echinochola crusgalli), finger
millet (Eleusine coracana), browntop millet (Panicum ramosum), koda or
ditch millet (Paspalum scrobiculatum), and teff millet (Eragrostis
tef).
Millet is generally applied to various grass crops whose seeds are
harvested for human food or animal feed. Sorghum is called millet in
many parts of Asia and Africa, and broomcorn is called broom millet in
Australia. Compared to other cereal grains, millets are generally
suited to less fertile soils and poorer growing conditions, such as
intense heat and low rainfall. In addition, millets require shorter
growing seasons.
Millets are generally considered minor crops except in parts of Asia,
Africa, China, and the Soviet Union. As a group, millets are used for
both forage and grain. When used as grain, they are considered a
cereal, but in the United States millets have lost a great deal of
importance in favour of other cereal crops such as wheat or rice.
Millet is believed to have descended from West African wild grass,
which was domesticated more than 40, 000 years ago. Its spread has
been through East Africa and then to India. Today, millet is a staple
food for more than 500 million people (National Research Council,
1996).
1
Area and production of pearl millet in the world is combined with
other millet crops (finger millet, foxtail millet etc), therefore it
is difficult to obtain data for pearl millet crop alone. However,
pearl millet accounts for almost half of global millet production
(VASAT). National Research Council (1996) reported that area planted
to millet is estimated at 15 million hectares in Africa and 14 million
hectares in Asia, with global production exceeding 10 million tons
annually (National Research Council, 1996).
Africa accounts for 60 per cent of world millet area, while Asian
countries occupy 35 per cent of world millet area. European countries
account for 4 per cent, while 1% is in North America. In general,
developing countries in Asia and Africa contribute around 93 per cent
of total millet production in the world. Asia alone contributes 43 per
cent of world millet production. European countries produce 6% and 1%
is in North America (VASAT). In the quarter century since the early
1970s, African millet harvests increased 22 per cent, whereas other
regions registered substantial production declines. The percentage of
millet used in Africa for domestic food is rising steadily, but the
vast and still expanding millet areas continue to produce low with
very few fertilizer inputs. In many areas where millet is the staple
food, nothing else will grow. However, besides providing food for
human, among its numerous other uses, millet stems are used for a wide
range of purposes, including: the construction of hut walls, fences
and thatches, and the production of brooms, mats, baskets, sunshades
(IFAD, 1999), as well as fodder and stover for livestock feed.
Pearl Millet is the third major crop in sub-Saharan Africa, with the
major producing countries being Nigeria, Niger, Burkina Faso, Chad,
Mali, Mauritania and Senegal in the west; Sudan and Uganda in the
east. In Southern Africa, maize has partially or completely displaced
millet because of the predominance of commercial farming.
Table 1: World Area and Production of Major Grain Crops during 2005
Crop
Area (Million ha) Production(Million Ranking by Land
MT)
Area
Wheat
216
626
1
Rice
154
615
2
Maize
147
692
3
Barley
57
138
4
Sorghum
43
57
5
Millet
27
36
6
Source: VASAT
2
Primarily, a tropical plant, pearl millet is often referred to as the
‘Camel’, for its exceptional ability to tolerate drought. It is a crop
of hot and dry climates, usually grown in areas where rainfall is not
sufficient (200-600 mm) for maize and sorghum cultivation. It is able
to produce reasonable yields on marginal soils, where other crops
would fail. Even with minimal rainfall, the crop will still produce
reasonable yields. It will however, responds very favourably to slight
improvements in growing conditions such as irrigation and tillage
(Leisinger et al., 1995). Thus, pearl millet is a widely grown rainfed
cereal crop in the arid and semiarid regions of Africa and southern
Asia. In addition, in other continents, it is grown under intensive
cultivation as a forage crop. It is grown by millions of resourcepoor, subsistence level farmers (IFAD, 1999) with percentage of millet
used for domestic consumption rising steadily in Africa (World Bank,
1996). The food value of pearl millet is high with trials showing that
it is nutritionally superior to maize and rice. The protein content is
higher than maize and has a relatively high vitamin A content.
The Influences
Millet:
of
Agroclimatological
Variables
on
Pearl
The climate of most pearl millet producing areas can typically be
described as hot and dry. Pearl millet has become the primary staple
food crop in these areas because nothing else will produce a crop on a
reasonably consistent basis. Five climatic factors are of particular
importance to pearl millet production: rainfall, air and soil
temperatures, daylength (photoperiod), radiation and wind. The impact
of these variables is dependent on the developmental stage of the
crop. The development of pearl millet can be broadly divided into
three growth stages (Begg, 1965): GS1: Growth stage one or sowing to
panicle differentiation GS2: Growth stage two or panicle initiation to
flowering (floral induction) GS3: Growth stage three or flowering to
grain maturity.
Rainfall:
Millet production depends almost entirely on rainfall as its moisture
supply. Therefore the amount and distribution of rainfall are
important factors in determining the ultimate productivity of the
crop. Poor soil moisture at sowing reduces seedling emergence leading
to poor crop establishment. Farmers often re-sow with subsequent
rains.
Temperature:
Numerous studies have been carried out over the years on the effects
of air and soil temperatures on the germination, growth and yield of
3
pearl millet (Ong, 1983a; Ong, 1983b; Gregory, 1983; Khalifa and Ong,
1990). Pearl millet development begins at a base temperature around 12
oC, an optimum temperature between 30-35 oC and a lethal temperature
around 45 oC). The base temperature has been shown to be fairly
constant regardless of the stage of development (Ong, 1993a). In the
Sahel, temperatures are usually high because of high radiation load
and scarce rainfall. In West Africa the problem is further complicated
by sand blasting and the burying of young seedlings under the sand.
Daylength/Photoperiod:
Daylength, or photoperiod, is a critical control in the initiation of
the reproductive phase of the millet in many pearl millet cultivars.
Photosensitive cultivars are grown as long season crops while nonphotoperiodic cultivars are grown as short season crops (The Syngenta
Foundation for Sustainable Agriculture, 2003). In such environments,
photoperiodic control of flowering provides an opportunity to sow
whenever the rains begin but ensures that flowering and grain filling
occurs when the moisture regime is most favorable (Mahalakshmi and
Bidinger, 1985).
Solar Radiation:
Solar radiation is an important asset in crop production. The amount
of distribution of incoming radiation sets the limits for dry matter
production. Radiation has two roles in crop production, namely the
photosynthetically active radiation (PAR) for photosynthesis and the
thermal conditions for physiological processes (World Meteorological
Organization, 1996). Fortunately radiation is seldom a limiting factor
in the tropics.
Wind:
In West Africa, heavy winds associated with thunderstorms are common
during the crop season. These winds are laden with dust particles that
reduce the visibility and incoming amount and quality of radiation,
and form deposits on leaf surfaces that may affect photosynthesis
(WMO, 1996). On the sandy soils in the southern Sahel, wind erosion
owing to frequent sand storms, especially at the beginning of the
rainy season, is one of the constraints to crop growth (Michels
et.al., 1993). If sufficiently buried, the crop must be replanted.
Surviving plants from partially covered crop stands showed delays in
growth and development, in addition to lowering plant height and leaf
number significantly. Grain yield from unaffected stands were nearly
twice that of partially covered stands.
4
Management aspects of the crop in the various environments:
Traditional cropping systems in the Sahel are essentially a continuous
pearl millet/cowpea intercrop grown at low plant populations with no
chemical fertilizers and all production operations are done manually
(World Bank, 1996). On the sandy soils of Africa pearl millet is
typically planted either in a dry seedbed or immediately after the
first rains. Rainfall can be sporadic, particularly early in the rainy
season. However, because prolonged droughts can occur after sowing and
during early the early seedling stages, growth can be greatly
hindered. Since the total rainfall in these areas is still limited the
timing of the early rains is very important for crop develop. Drought
conditions, combined with high temperatures can be very detrimental to
the emergence and development of the young seedlings. Strong winds can
also cause damage the young seedlings and cover them with sand. Land
preparation/cultivation: In most cases, little or no tillage is done
and weeding is started right after emergence in Africa.
In sandier soils, the ground is dug over with a hoe and weeded prior
to planting. Warm soils are required since higher temperatures
encourage rapid germination (The Syngenta Foundation for Sustainable
Agriculture, 2005). Millet is sown in hills, 10-15 cm deep, dug with a
hand hoe, and weeding is carried out with a hoe that cuts the soil 2-5
cm under the surface. This not only cuts the roots of the weeds, but
also breaks the surface crusts and facilitates water infiltration (De
Rouw and Rajot, 2004). All these cultivation practices are common
throughout the African Sahel where millet is grown on sandy soils.
The recommended practice is to plough the land twice immediately
following harvest to bury the stubble and weeds and once or twice at
sowing to prepare a fine seedbed. However, land preparation is usually
inadequate, particularly in moisture-stress areas farmed by resource
poor farmers, where the land is usually ploughed only once. Also, even
for those areas where tractors are available, the specialized
implements needs for cultivation and harvesting have not been
developed. Because prolonged droughts can occur after sowing and
during the early seedling stage, growth can be greatly hindered. Once
the crop is established, there are a limited number of options
available to the producer in the event of problems with insects and
diseases.
Date of Sowing: A major problem of rain-fed agriculture in semi-arid
regions with short rainy seasons is how to determine the optimum
sowing date. Traditional farmers have developed their own definitions,
using accumulated experience and/or calendars based on local beliefs
5
(Onyewotu et al., 1998). Some more scientific methodologies have been
developed.
Fertility/Water Use Efficiency: The most common soil fertility
management practice with pearl millet is fallowing. Sometimes,
manuring is practiced either through corralling (the animals spend the
nights on the field during the dry season) or spreading the manure
across the fields (DeRouw and Rajot, 2004). The cultivation practices
are the same on manured and fallowed land are common throughout the
African Sahel where millet is grown on sandy soils. Pearl millet
responds well to additional plant nutrition. In a four year study in
Oklahoma(USA) (Noble Foundation, 2006) to evaluate different summer
forages, pearl millet was as productive on average as sorghum and
sudan, but required five times less nitrogen (N) and was more
efficient with the N it received. Increased fertility also results in
an increase in water use efficiency. In a four year study at the
ICRISAT Center in Niger, the increased yield due to the application of
fertilizer was accompanied by an increase in the water use efficiency
(WUE) in all four years. The beneficial effect of fertilizer could be
attributed to the rapid early growth of leaves which can contribute to
a reduction in the evaporative losses from the soil and increased WUE.
(Sivakumar and Salaam, 1999) Over the four seasons, the average
increase in WUE due to the addition of fertilizer was 84 percent.
Moisture
conservation:
Evaporation
from
the
soil
surface
constitutes a large proportion of evapotranspiration of pearl millet
fields in West Africa. Practical methods of reducing evaporation from
soils to conserve water are lacking in West Africa (Payne, 1999). The
use of organic mulch during the growing season would be a simple
solution except that most of the crop residues are feed to livestock
or used for building materials during the long dry season. Plastic
mulch would also be effective, but such materials are too expensive or
generally unavailable in most of West Africa. Pearl millet leaf area
indices are typically <0.5 during the early growth stages in semi-arid
West Africa, causing transpiration to be a relatively small fraction
of ET (Daamen, 1997). The probability of dry spells of ten days or
more is high (Sivakumar, 1992), and crop water supply is often
exhausted, necessitating resowing after the next sufficiently large
rain event. Delayed sowing is generally associated with yield decline
in pearl millet (Reddy and Vissar et al., 1993). Any reduction of
evaporation (E) during this and subsequent periods would increase
water supply for crop growth and reduce the risk of resowing. The
hilaire is a shallow cultivating, traditional hoe that has been used
for centuries on sandy soils in West Africa to control weeds. It is
6
pushed and then pulled by the user such that the blade cuts the roots
of weeds 4 to 5 cm below the soil surface. The affected surface is
pulverized and loosened. Furthermore, the color of the soil’s surface
becomes darker because the underlying soil layer has greater organic
matter pigmentation. (Payne, 1999). Hillel (1982) has suggested that
one way to control evaporation during the first stage is to induce a
temporarily higher evaporation rate so the soil surface is rapidly
dessicated. This hastens the end of the first stage and uses the
hysteresis effect to help arrest or retard subsequent flow. The use of
the hilaire leaves the soil surface in a state close to what Hillel
has proposed. In studies by Payne (1999) it was clearly demonstrated
that ET was 45 mm less in tilled plots compared to untilled plots. In
areas with 200-600 mm of 15 precipitation this represents from a
significant reduction in moisture loss. However because of limitations
in labor, it would be unrealistic to expect subsidence farmers to till
entire fields with the hand-operated hilaire after each rain event. In
order to render this technique useful to farmers, and animal drawn
implement would need to be designed that reproduces the hilaires’
effect. A related issue is the practice of planting pearl millet in
widely spaced rows. This is perceived to be a practice that reduces
pearl millet crop failure. As a result, the leaf area index (LAI) in
most fields seldom reaches 1.0. Even in more intensively managed
fields, LAI seldom exceeds 2, and the period during which LAI exceeds
this value constitutes only a small portion of the entire growth
period (Payne, 2000). Payne (1997) found that increasing plant density
from 5000 to 20000 “hills” ha -1 increased yield and ET efficiency
significantly even under low fertility even during 1984, the driest
year on record. There appears to be no justification, at least in
terms of crop water use, to the use of wide spacings. Canopy cover can
also be increased by the introduction of an intercrop. In semiarid
West Africa , pearl millet is most often intercropped with cowpea.
Intercropping with cowpea has been reported to increase pearl millet
grain yield by 15-103% in Mali. Varieties: Although pearl millet in
India is the crop of the rural poor in the harshest agricultural
environments in India, F1 hybrid seed is used to sow over half of the
10 million ha on which this crop is grown because the potential yield
obtainable from such hybrids more than pay for cost of the seed and
other risks associated with hybrid-cultivation (Wisard Project
Information 1999). The amount of money required to purchase the seed
to sow an average holding is small (e.g., equivalent to L3 for seed to
sow 1 ha of the most expensive commercial hybrid. Although pearl
millet hybrids often give better grain yields than local openpollinated cultivars, the genetically uniform single-cross hybrid
cultivars currently available in India are more vulnerable to
epidemics of pearl millet downy mildew. Such epidemics constitute the
7
major risk to cultivation of well-adapted pearl millet hybrids. Losses
in individual fields can reach nearly 100%, and are estimated to
average
14%
across
10
million ha
in
India.
Intercropping:
Intercropping, or planting two or more crops in the same field is one
means of better utilizing limited resources. A study to quantify the
use of resources in dominant millet-cowpea (M-C) and millet-sorghumcowpea (MS- C) intercropping systems was carried out by Oluwasemire,
et.al. (2002) using standard farming practices under the low rainfall
and poor nutrient supplies in the semi-arid zone of Nigeria. When
intercropped, pearl millet used water more efficiently for grain
production. It showed a better adaptation to moisture stress by
producing similar harvest indices in sole and intercropped millet. The
harvest index was defined as the ratio of the yield of grain to the
total dry matter production of the plant. Millet was also the dominant
crop in dry matter production when intercropped. This was due to the
faster growth and higher tillering rates of millet, especially at low
plant densities.
Fertility Practices
Millets are generally grown on less fertile soils. All millets respond
to nitrogen and phosphorus fertilizers, but there are only broad
guidelines on fertility practices for millets. Generally 40–100 lb of
nitrogen and 30–60 lb of phosphorus per acre are adequate to produce
hay or seed, but most forage crops for grazing should be fertilized
more to enhance forage productivity and volume. The amount of forage
needed and the number of livestock to be pastured will be the
determining factors in planning nitrogen fertility practices. Nitrogen
requirements for heavy forage production and heavy grazing will likely
be double those required for hay or seed crops.
Cultural practices for millets.
Maturity days from Millet type Planting date Seeding rate Soil
conditions planting(for seed lb/A production) Proso May-July 20–20
almost any soil 60–75 Foxtail Mid-May-August 10–20 all soils 75–90 (5
Ib for seed (except coarse sand) production) Pearl April-July 5–15
almost any soil 60–70 Japanese April-July 20–25 medium to 45–60 heavy
soils Finger April-June 8–10 almost any soil 90–120 Browntop May-July
10–20 almost any soil 45–60 Phosphorus requirements will also be
higher than those for hay or seed crops. A soil test is recommended to
evaluate nitrogen and phosphorus fertilizer requirements and to
indicate the deficiency of any of the other required nutrient elements
that might limit productivity. These nutrient elements include
potassium, sulfur, calcium, magnesium, iron, copper, boron, manganese,
zinc, molybdenum, and chlorine. One or more of these nutrients may be
limiting in the less fertile soils used by millet producers.
8
Weed Control Options
Weed control in any crop production practice is limited to five
options: preventative, biological, cultural, mechanical, and chemical
control. Choice of a particular method or methods depends upon the
weed spectrum, crop rotation sequence, and other factors. It is
important to employ several options in millet production because
chemicals that can be used for weed control are severely limited.
Preventive control options begin with planting clean, weed-free seed.
In addition, producers should make sure all equipment used to plant
millet is free of weed seeds. Controlling weeds along ditchbanks,
roadsides, and field margins will also help prevent weed seed from
entering fields. At the present time there are no known biological
controls for weeds in millet Cultural control options include narrow
row spacing, adapted variety selection, and crop rotations, all
practices that will provide a competitive edge for the millet crop.
Mechanical controls should be used to prepare the seedbed prior to
planting millets and where millets are planted in rows for seed,
giving producers a head start on weed control. Chemical weed control
options are limited for millet production. The most troublesome weeds
in millet production are summer annual broadleaf weeds and some annual
or perennial grasses. In addition, there may be problems with
perennial broadleaf weeds if they are present in fields used for
millet production. For pearl millet production, producers can use
atrazine as a preplant incorporated or preemergence treatment with
rates of 0.5–1 lb ai/A. Crop rotation restrictions apply for this
herbicide application, and the producer should consult the label. In
some areas Banvel® (dicamba) is labeled under a special local-need
labeling to control annual broadleaf weeds. Producers should contact
their local county agent or the New Mexico Department of Agriculture
for additional information. Formula 40® (Alkanolamine salt of 2,4D) is
labelled for control of broadleaf weeds in millet In some areas where
2,4-D-sensitive crops are
INSECT AND DISEASE CONTROL
The principal insect problems in millet production are grasshoppers
and armyworms. In some cases chinch bugs or false chinch bugs may also
cause economic damage. These insect problems can generally be
controlled with Sevin® XLR Plus. DiPel® and Biobit® can be used to
control armyworms. Follow the label directions for small grains, hay
crops, or forage crops depending upon cropping plans. If other insect
problems are noted, consult the local county agent or the New Mexico
Department of Agriculture for special local-needs labels and
chemicals.Foxtail millet can harbor the wheat curl mite, a vector of
wheat streak mosaic virus in wheat. Therefore, wheat should not be
planted following production of foxtail millet unless sufficient time
9
is allowed to break the curl mite cycle (probably 3 weeks). Diseases
in millets are not widespread; however, there may be particular
diseases that occur with some millet species. The most important
diseases include mildew, bacterial blight, kernel smut, and leaf spots
with foxtail millet; bacterial stripe and head smut with proso millet;
head Smuts with Japanese millets; and helminthosporium with finger
millet. The impact of head smuts can be reduced with quality seed
purchases and planter box fungicide treatments. Other diseases,
especially the bacterial blights, are not easily controlled. Copper
fungicides are used to control blights; however, several applications
may be necessary from the onset of blights. Consult with the local
county agent or New Mexico Department of Agriculture for guidelines on
these diseases. Mildew and seed rots can be controlled with Apron®25 W
applied as a seed treatment at planting. Consult the label prior to
using the product. Leaf spots can be controlled with fungicide
applications; however, in New Mexico weather patterns are generally
not favorable for spread of the disease. Information herein is
presented with the understanding that no discrimination is intended
and no endorsement by the New Mexico Cooperative Extension Service is
implied.
Overview
Pearl millet is a warm season annual grass that is best known in the
U.S. as a forage crop. Estimated U.S. area planted to pearl millet for
forage use is 1.5 million acres. New varieties of pearl millet,
however, are being developed for use as a grain crop. These new hybrid
types of pearl millet are shorter in stature for easier combining, and
higher in seed yield. Use of pearl millet grain on a commercial basis
only began in the U.S. in the early 1990s, but has led to production
on several thousand acres in Georgia and Florida. Most of this initial
pearl millet production has been for poultry feed, although the crop
shows good feed potential for other types of livestock as well. Some
pearl millet has been grown for birdseed.
Pearl millet was domesticated as a food crop in the tropical region of
East Africa at least 4,000 years ago. Its use as a food grain has
grown over the centuries, with an estimated 64 million acres of pearl
millet being grown in Africa and India (this acreage is equivalent to
the total U.S. corn crop). The crop is used for a variety of food
products, and is even made into a type of beer.
Plant Description
10
Pearl millet [Pennisetum glaucum (L.) R.Br.] grown for grain has a
growth habit similar to sorghum. Pearl millet is a warm season crop,
planted in early summer when soils have warmed up. In Missouri, it
reaches the stage of 50% flowering in about 60 to 70 days from
planting. The flowers and seeds occur in a spike at the end of the
stem or tillers, looking somewhat like a cattail or bullrush head.
Including the grain head, the plant will typically be about 4 to 5
feet tall in Missouri, although height can vary from 3 to 6 feet
depending on variety and growing conditions. The crop is primarily
cross pollinated, and following pollination, it takes a flower about
30 more days to develop into a mature seed. Grain heads will mature a
few weeks prior to leaf dry down, but seed shatter is not usually a
problem. When planted around June 1 in Missouri, it will usually be
ready to harvest in late September.
Like any grain crop, pearl millet will yield best on fertile, well
drained soils. However, it also performs relatively well on sandy
soils under acidic soil conditions, and when available soil moisture
and soil fertility are low. This adaptation reflects pearl millets
origin in the Sahel region of Africa, where growing conditions are
difficult. Pearl millet appears to have relatively fast root
development, sending extensive roots both laterally and downward into
the soil profile to take advantage of available moisture and
nutrients. The crop does best when there are plenty of hot days,
although it has been successfully produced in cooler areas such as
North Dakota. In general, pearl millet fits in the same areas of
adaptation as sorghum (milo), except that it is somewhat more drought
tolerant and has a little earlier maturity. It also tolerates low soil
pH better than sorghum.
Utilization
Although pearl millet was developed as a food crop and is still
primarily used this way in Africa and India, its grain is most likely
to be used for animal feed in the U.S. Several studies have been
conducted on its potential for various types of animals, including
poultry, ducks, cows, hogs, and catfish. In general, it performs
comparably to corn in the diet for these animals, with small
advantages
in
certain
situations.
Typically the protein content of pearl millet is 45% higher than feed
corn and is also 40% higher in lysine. This higher protein and other
feed characteristics have helped drive the interest in the grain by
poultry producers and other livestock producers. Pearl millet is much
lower in tannin than sorghum and its seed is about half the weight of
a sorghum seed. Seeds are pointed at one end, rounded at the other and
11
primarily light colored with a blue or gray tinge to them.Markets and
Economics
Markets and Economics
The main commercial market to date for grain-type pearl millet has
been the broiler market. Lack of familiarity with the crop has limited
its use in other livestock feed markets. However, as feed formulators
and buyers become more familiar with the crop, its potential markets
will expand. In the meantime, pearl millet grain can certainly be used
on-farm as a feed for cows, hogs or poultry. A one-to-one substitution
of pearl millet for corn in a feed formulation is usually appropriate.
Given its comparable feed value to corn, pearl millet has been priced
based on corn prices, or sometimes at a slight discount relative to
corn. In situations where pearl millet delivers superior feed value to
corn, it should in the long run receive a premium, but it will take
time for such market value to be realized. However, yields of current
pearl millet are not competitive with corn or even sorghum on good,
fertile soils. Pearl millet has a competitive advantage over corn and
sometimes sorghum on sandier soils in moisture-limited situations.
Yields of grain-type pearl millet are expected to rapidly improve with
the release of new hybrids over the next several years. At this time,
4000 to 4500 pounds per acre would be a reasonable yield on good
soils, with 3000 pounds typical on more marginal soils. Thus, gross
income based on these yields will be well under $200 per acre if corn
is priced below $2.50/bushel. Even though production costs on pearl
millet are low (comparable to corn and sorghum), grain yields need to
be increased by breeders to help make the crop competitive on a larger
acreage.
Another potential market for pearl millet is as part of wild birdseed
mixes. Although no research has been done on its use as a birdseed, it
has been repeatedly noted that a number of songbirds, including gold
finches and juncos, enjoy feeding on the seed. Sorghum is often used
in birdseed mixes, but pearl millet may be more attractive to certain
songbirds. The birdseed market could potentially absorb tens of
thousands of acres of pearl millet grain production. In the mid-1990s,
a few thousand acres of pearl millet were sold into the commercial
birdseed market. The birdseed market could generate higher prices for
pearl millet than the feed market, provided the demand is strong
enough. Price initially would depend on whether the pearl millet was
substituted for sorghum (low value) or proso millet (moderate value)
in birdseed mixes.
12
Even though pearl millet is used as a food crop in other countries, it
is unlikely to be used as a food in the U.S. in the near future. No
research is being conducted in the U.S. on its food use potential, and
little is known about its potential for use in industrial products.
How to Grow Pearl Millet
Although pearl millet has been researched as a grain crop alternative
in the U.S. for less than a decade, basic production guidelines have
been developed. Several field trials with pearl millet were conducted
by the author at University of Missouri research farms during 19911994. In general, pearl millet management is very similar to growing
sorghum. Pearl millet can be considered a “low-input” crop, but does
respond
to
fertile
soil
conditions
and
good
management
practices.Variety Selection and Seed Sources
Variety Selection and Seed Sources
Development of grain-type pearl millet varieties is currently being
done by university and USDA plant breeders, who can then release their
cultivars as public varieties or under license to a private company.
To date, the only available varieties are HGM 486 and HGM 686. HGM 686
has performed better in Missouri. HGM varieties are available from
Crosbyton Seed (800-628-6551), a seed dealer in Texas. A new variety
is expected for purchase in 2004. This variety is shorter season than
HGM 686 and offers the potential as a double crop in southern
Missouri. Pearl millet varieties are hybrids, so new seed much be
purchased each year. Producers seeking grain-type pearl millet are
cautioned to clarify that the seed they are purchasing is not a
forage-type pearl millet. The forage types are much taller (7-8 feet)
and have low seed yield.
Planting
Soil temperatures should be at least 65°F. or warmer before pearl
millet is planted. In Missouri, optimum planting time is early June,
with a range of mid-May to mid-June being appropriate. Pearl millet
can potentially be planted as a double crop after winter wheat or
winter canola in the southeastern part of the state, but it has too
long a season for double cropping elsewhere in the state.
Seeding rate is recommended at 4 pounds per acre. An exact seeding
rate is not critical, because pearl millet can partially compensate
for a poor stand by increasing the number of tillers. Seeding depth
should be 1/2 to 1 inch deep. No-till seeding is feasible, although
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the shallower seeding depth compared to corn or soybeans can make
proper control of planter depth (through surface residue) more
challenging.
A variety of row widths are appropriate with grain-type pearl millet.
Previous work with pearl millet in Missouri has been based on 30 inch
row widths. This allows row crop cultivation for weed control. At this
row width, pearl millet will normally have enough leaf development to
“close the row.” In other states, narrower rows have sometimes given a
yield improvement over wide rows. The narrower rows prevent using a
cultivator for weed control, but ground shading by millet leaves
occurs earlier, helping suppress some weeds. On sandy soils, wider row
spacings may be better since they will allow individual plants to
develop
more
lateral
roots,
due
to
less
row-to-row
competition.Fertility Management
Fertility Management
Pearl millet will respond to good soil fertility, but does not have a
high nutrient demand. It can be considered similar to sorghum in its
fertility needs; rates recommended for sorghum by a soil test lab can
be applied to pearl millet. Millet may need somewhat less nitrogen
than sorghum, because current varieties yield less than sorghum.
For conventional production, about 40 to 80 pounds of nitrogen
fertilizer per acre should be applied on most Missouri soils. The
lower amount is appropriate if the millet follows a legume such as
soybeans. Since nitrogen needs are modest, fertilizer nitrogen can be
applied sidedress rather than preplant if appropriate. Nitrogen needs
can certainly be met from organic sources, such as animal manure or a
leguminous cover crop.
Phosphorous and potassium needs of pearl millet have not been well
studied, but again the rule of thumb is to use rates recommended by a
soil test lab for sorghum. Phosphorous response is likely to be
improved if the P is banded near the seed. Liming is probably not
necessary on most Missouri soils for pearl millet, since it has been
reported to be fairly tolerant of low soil pH.
Pest Management*
Weed
control
Only a few herbicides are currently labeled for pearl millet. Peak and
2,4-D are labeled for broadleaf control with pearl millet, while
Banvel can be used to control some grasses, though it is still
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primarily a broadleaf herbicide. There is some question as to whether
these labels apply only to forage millet or also cover grain-type
millet. Since pearl millet is planted relatively late, two preplant
tillage operations are recommended, first to stimulate germination of
weed seeds, then, several days later, to kill weed seedlings prior to
planting. If planted in wide rows, row cultivation for weed control
should be planned, especially if herbicide control is ineffective.
Pearl millet is somewhat slow growing as a seedling, making preplant
weed control important, but soon takes off and competes well with
late-emerging weeds. With no-till planting, weed control by herbicides
or effective use of cover crops is necessary to successfully establish
pearl millet.
Insects
The only insect pest of pearl millet noted so far in Missouri is
European corn borer. Chinch bugs have also been a problem on occasion
in other states. Normally insecticides are not needed on pearl millet.
In the event they are, there are several insecticides labeled for
millets, including Malathion, Methaldehyde, Methoprene, Myphosphide,
Phostoxin, Pyrellin, Seven, Success and Telone. General purpose
organic materials such as certain Bt and pyrethrin products may be
used on most crops, including pearl millet.
Diseases
No significant disease problems have been noted in four years of field
testing pearl millet in Missouri. Rust has occasionally appeared in
southeastern states, usually on later planted pearl millet. New rust
resistant varieties are being developed. Seedlings trying to emerge
from cold, wet soils sometimes are killed by damping off caused by
soil pathogens. Fungicide applications are not recommended for pearl
millet, but there are labeled products for millets: Maxim, Maxim-XL,
Mefenonxam and Metalaxyl.
Birds
Birds can cause damage to pearl millet fields. The grain heads are
carried on a stalk strong enough to serve as a perch for most birds
that peck away at the exposed seed on the grain head. In small
Missouri test plots (less than an acre), birds have occasionally eaten
almost every seed. In fields of forty acres or more, damage will
usually be much more limited, typically less than 5 to 10% loss, if
damage occurs at all. Chance of damage can be reduced by keeping pearl
millet fields away from tree lines or woods if possible.
Organic
production
Pearl millet is a crop that should need little in the way of pesticide
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use, and can be grown effectively with organic methods for the organic
livestock feed market, which pays a premium for feed materials in many
areas. Using cover crops or manure to boost fertility, employing
cultural and mechanical weed control, and incorporating crop rotation
can allow successful organic production of this crop.
*Pesticides mentioned as being labeled in this publication are based
on reference lists published in the Thomson Publications “Quick Guide”
on crop pesticides, 2002 edition. These lists are believed to be
accurate, but given the changing nature of pesticide registrations,
labels and relevant government pesticide regulations should be checked
before applying any herbicide or other pesticide.
Harvesting and Storage
Current pearl millet varieties produce seeds that are ready for
harvest before the plant is dried down. Although the seeds are not
likely to shatter, it is desirable to harvest as soon after seed
maturity as plant dry down allows, to avoid unnecessary grain loss to
birds or storm caused stem lodging. If pearl millet is planted by
early June, leaf dry down is usually complete by late September, but
weather conditions can greatly affect dry down. The plants will
continue to stand after a frost, so a delayed harvest is possible.
An all crop or small grain combine header is appropriate for
harvesting pearl millet. Combines must be adjusted to properly thresh
the small seed of pearl millet. A good starting point for the combine
settings are those recommended for sorghum. Air speed may need to be
reduced, and screen sizes may need to be changed on combines that use
replaceable threshing screens. Efficient threshing can help improve
the value of the millet for livestock use, by minimizing chaff and
other materials. Since the grain heads are at least three feet off the
ground, cutter bars can be run above the ground.
More research is needed on appropriate storage methods for pearl
millet, but current recommendations are that the grain be stored at a
maximum moisture of 12-13%. Since the seed size is smaller than
sorghum and corn, it is more difficult to force air through it in a
grain drier. When trucking millet long distances, it is prob- ably
best to tarp the grain to prevent seed loss.
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