Millet, production

Pearl millet is a hardy and drought tolerant crop and is mainly grown in dry land areas with low rainfall (200-600mm) and marginal soil fertility. Pearl millet accounts for approximately 50% of the total world production of millets.

It is widely grown in semiarid areas of Africa and India. In the USA, pearl millet is mainly grown for hay, silage and forage.

The crop can be planted on dry seedbeds before the onset of the rains. Rigorous seedbed preparations are not necessary. In sandy soils in Africa, the ground is dug over with a hoe and weeded prior to planting. Warm soils are required since high temperatures encourage rapid germination. However, prolonged droughts at sowing and during early seedling stage greatly hinder growth.

Pearl millet is propagated from seed and performs best on light loams but can also do well in sandy soils characterized as aridsols and alfisols.

Planting can be done in four ways:

1. broadcasting and covering the seed lightly with soil,
2. drilling the seed directly into the soil,
3. plant and chop method, and
4. sowing the seed in nurseries and transplanting to the field.

The crop is the transplanted to the field 3 weeks after planting. Planting depth varies from 13-50 mm.

1.0.1 Spacing and Seed Rates

The spacing varies depending on the availability of soil moisture and amount of organic matter in the soil. In the Sahel, plants are thinned to about 3-6 plants/planting hole with a plant population as low as 6000 plants/ha (Fussell, 1992).

The seed rates range from 3-9 kg/ha (Purseglove, 1988) and 6-10 kg/ha when the crop is drilled in rows of 35-70 cm apart. Using plant and chop method (especially in African Sahel and Sudano zones), a few seeds are dropped in holes dug with a hoe, 45-90 cm apart and covered.

1.0.2 Tillering

Tillering is very important in pearl millet because crops are often grown at low plant populations under semiarid conditions. Both basal and axillary tillers are formed. Basal tillers are usually formed between day 13 and 40 after sowing. These tillers can contribute up to 50% of the total yield under rainfed conditions.

1.1 Fertilizer Application

Pearl millet is capable of growing in soils of marginal or low soil fertility status. Nutrient uptake is influenced by climate, nutrient availability (especially N₂) and moisture availability.

Fertilizer uptake under irrigation is doubled while in semiarid conditions the period over which N₂, P and K uptake occurs is greatly curtailed. It is therefore not economically prudent to have split fertilizer applications on pearl millet crop (under dry land conditions), as these cannot cause any meaningful yield increases. Under these dry land conditions uptake from N₂ fertilizer may be as low as 20-30% (Christianson, et al 1990b).

Several workers have reported that pearl millet is capable of extracting greater quantities of N₂, P and K from sandy loam soils. This could be attributed to the ability of the crop to root deeply and rapidly.

Where soil water is not limiting, pearl millet yield responses to N₂ fertilizer has been found to follow linear equation; Y= 0.68 + 4.49x2 (Norman et al, 1995); where Y is dry matter accumulation and X₂, amount of fertilizer applied. However, high N2 applications (60 kg/ha) may promote excessive vegetative growth and depress yields especially under dry land conditions.

Pearl millet requirement for Phosphorus (P) is not high. Rates above 66 kg/ha can depress yields if there is insufficient moisture in soil. Information available indicates that mycorrhizal fungi can significantly increase P uptake (ICRISAT, 1985).

Standard application rates vary from region to region and a soil test is usually recommended in order to establish limiting nutrients and exact quantities of nutrients to be applied.

Farmyard manure if available should be applied to boost crop growth. In cases where higher yields (>1 ton/ha) are anticipated, chemical/inorganic fertilizers should be used.

In African Sahel, weeds are controlled using a hand hoe or by hand pulling and should be done at early stages of crop growth. Other cultural practices that help the crop to out compete the weeds should be practiced.

These include planting clean weed-free seed, narrow spacing, adapted variety selection and crop rotations. In developed countries such as the USA, mechanized weeding is practiced and the crop is normally planted at spacings that permit use of mechanized weeders.

Maturity periods vary depending on the cultivar /hybrid and climatic conditions. In West African Sahel, there are two types of pearl millet usually grown in association with other crops.

These include Gero and Maiwa millet cultivars. The Gero millets are short season non-photoperiodic millets and mature within a period of 55-100 DAP. Meanwhile Maiwa millet varieties are long season photoperiodic millets and mature in about 120 DAP. In the USA, most cultivated pearl millet hybrids mature between 60-70 DAP.

Yields vary depending on mode of production and region. In India, yields range from 770-1,100 kg/ha under rainfed conditions and 1,100-3000 kg/ha under irrigation. In Africa Sahel and Sudano zones, yields range from 250-750 kg/ha under rainfed conditions.

Harvesting is done by cutting the heads from standing plants while in certain communities, it's done by cutting down the whole plant and later cutting off the head when it's fully dry.

References

Christianson, C.B; Bationo, A; Henano, J. and Vlek, P.L.G (1990b). Fate and Efficiency of N fertilizers applied to pearl millet in Niger. Plant and Soil 125, 221-31

Fussel, L.K. 1992. Semi arid cereals and grazing of West Africa. In: Field Ecosystems, Ed C.J. Pearson pp485-578. Amsterdam: Elsevier.

ICRISAT. 1985. Annual Report 1984. Patancheru, India. International Crops Research Institute for the Semi Arid Tropics. 7376pp

ICRISAT. 2004. CGIAR Millet Research. In: International Crops Research Institute for the Semi Arid Tropics Web site.

Mehra, K.L. 1963. Differentiation of Cultivated and Wild Eleusine species. Phyton, 20, 189-89

Norman M.J.T, Pearson C.J; and Searle. 1995. Ecology of Tropical Crops. Cambridge University Press. 430pp

Purseglove, J.W. 1988. Tropical Crops. Monocotyledons. Longman Group UK Ltd, Longman House, England. 607pp