Millet: Pre-Planting

Varietal diversification

Millet has a wide range of maturity periods. Some varieties mature in as little as 60 to 80 days (short duration) while others take about 100 days (medium) to mature.

Long season varieties can take up to 180 days to mature from planting. Cultivation of short-duration varieties reduces the risk of crop failure. In areas with two rainy seasons, millet can be grown during the short rains. Where rainfall is suffi cient, double cropping is possible after short-duration millet.

Using millet as feed for livestock

Basically, smallholder agriculture encourages the introduction of livestock into the farming system, as they transform plant biomass into animal products and provide manure for the crops. But where land is short and plant growth is limited due to scarce rains, there may be need to renounce to the introduction of livestock, or there may be need to remove livestock from the farming system to avoid competition to human food production and provide more biomass for soil fertility management. It may be more efficient to farm less land applying proper soil fertility management without using animal traction, than to manage a larger area poorly. If the stubbles, tree leaves and other plant materials are grazed by livestock, biomass will not be available for soil fertility management and the soil is left more or less bare through the dry season - creating unfavorable conditions for improvement of soil fertility. If the farm is managed without livestock, surplus grain legumes may be substituted for some livestock products and increased planting of a wider variety of legumes would improve the sustainability of the cropping system.

Where conditions allow, pearl millet can be grown for livestock feed where animals with high nutrient requirements such as growing animals, lactating dairy cows, or calves are allowed to graze on the growing crop. In this case, the pearl millet can be used either under a continuous or a rotational grazing sys-tem. For most efficient use of the pearl millet, animals can be turned into pastures when pearl millet has reached a height of about 50 to slightly over 60 cm.

The animals can be allowed to continue grazing until the pearl millet plants have been reduced to about 15 to 20 cm height. Overgrazing must be avoided, if the pearl millet is to be allowed to regenerate for the next rotational grazing phase.

Besides grazing, the pearl millet can be processed into hay and silage. Due to the thick pearl millet stems, the curing time in hay production is longer than with other hay crops, but the curing time can be reduced by crushing the stems, if facilities are available. The best times to cut the millet are: fi rst cutting at 60–65 days after planting when the plants are about 90 cm tall; thereafter at intervals of 30 to 35 days. For making silage, the pearl millet should be cut at boot to soft dough stage as this gives an optimal nutritive value to the silage. The plants should be wilted before chopping for storage.

Choosing the right variety to plant

Millet varieties differ in many respects. The time to flowering, plant height and leaf numbers vary among varieties. Millet occurs with different shape, structure and size of the panicle. In some varieties, the panicle is open and erect; in others it is compact and head-like. Other attributes which vary include i) tolerance to drought, ii) pest (including birds) and disease tolerance, iii) tillering capacity, iv) height of plant, v) time to maturity, vi) yield, vii) grain colour and size, viii) size of hairs (bristles) on the panicle, ix) length of grain storage, x) hull and grain processing characteristics, and xi) milling quality.

Although traditional cultivars have a low yield potential, they have the advantage of being well adapted to local growing conditions. However, improved cultivars have shorter growth duration of 75 to 80 days, higher protein content, and may attain higher yields even under conditions of drought-stress and low nutrient level. Some cultivars are resistant to diseases like blast and rust. The local extension services may be able to give more information for choosing the right millet cultivar.

Recommendations to farmers for good variety selection:

• Use early and uniform maturing varieties to increase yield security in climates with low rainfall, as periods of drought can be avoided. Cultivation of short-season cultivars furthermore may allow growing a second crop, ideally a legume.
• Before scaling-up production of a new cultivar, test it first on a small scale.
• For best results and to minimize risk of crop failures, choose cultivars that do well with average rainfall, show good vigour at emergence, abundant tillering, are resistant or tolerant to downy mildew, smut, earworm and Striga and produce good yields.
• Hairy panicles prevent the grains from being eaten by birds. For processing, the consistency of the grains and the vitreosity of the endosperm are also important characteristics.

Seed selection and saving

Traditionally, farmers saved seeds from one season for sowing during the next season. Over the years, breeding programmes have produced improved varieties of millet of which farmers can buy seed and grow. However, there are farmers who still save their own seed for various reasons. To save own seed, the farmers select panicles from the best plants which they identify before harvest. Panicles from these plants are then harvested and stored separately from those to be used for consumption. Some of the attributes which farmers consider in selecting plants from which to harvest seed are plant vigour, tillering capacity, plant height, absence of disease infection, panicle size and grain size.

Panicles are not always selected before harvesting. In some cases farmers only select the panicles for seed saving after harvest. With this method they are not able to tell the characteristics of the plants from where the panicles were harvested. It is therefore advisable for the farmers to use the fi rst approach where panicles are selected before harvesting so that farmers also consider the plant characteristics in selecting the seed.

After thorough drying on wooden racks or on a fl at rock preferably in the shade until they are dry (after one week or when the seed moisture content gets to 12 %), the panicles are threshed and seed is further dried if necessary, particularly if the grains are larger and drying on the panicle is slower. When properly dried, the seed is mixed with ash and then stored in bags in huts used for cooking where the smoke and heat help to preserve the seed from pests and diseases.

Seed can also be stored in clay pots to keep them cool and protect them from pests. Alternatively the seed can also be stored with leaves of plants such as neem and tephrosia, or with pyrethrum to deter pests. If farmers intend to keep the seed for longer periods, seeds should be dried to around 8 to 9 % moisture while even lower moisture of 5 to 7 % is encouraged for long term storage of the seed. To prevent the seed from absorbing moisture during storage, they should be stored in sealed containers which are not permeable to moisture.

Controlling diseases in millet seed

Seed borne diseases such as ergot (described in more detail in a later section) can affect the panicles and carry the pathogen to the next crop. Farmers are encouraged to remove affected panicles/plants to avoid diseases spread. However, the infected seeds must also be eliminated from the seed lot. In India, the salt water fl oatation method is used to separate or eliminate ergot infected seeds.

Treating the seeds with 600 g of Azospirillum (Azospirillum brasilense, a nitrogen-fi xing bacterium found in the rhizosphere of various grass species) per 4 kg seed and with Phosphobacterium will enhance the availability of nitrogen and phosphorus to the subsequent millet crop.

Seed treatment and preventing seed from absorbing moisture during storage

Non-toxic chemicals can be used to protect pearl millet seed. The method reported by TamilNadu Agritech is to treat the seeds with a halogen mixture at the rate of 4 g per kg of seeds. Calcium oxychloride + calcium carbonate + Albizia amara leaf powder are mixed in the ratio of 5:4:1 and stored in an air-proof container for a week to prepare the halogen mixture before applying it to the seed. To prevent the seed from absorbing moisture, moisture vapour proof containers like polyethylene bags (of 700 gauge thickness) must be used for seed that has moisture content 8 % or less. Polylined cloth bags can be used for seed at 10 % moisture content. It is important to place the bags on wooden pallets to prevent absorption of moisture from the fl oor and walls. If large quantities of millet seed have been produced, bags should not be over-stacked (more than 7 bags per stack) as this will exert pressure to the seeds in the lower bags causing loss of seed viability.

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