In this article we will discuss about:- 1. Origin and Distribution of Pearlmillet 2. Area and Production of Pearlmillet 3. Harvesting and Storage 4. Water Management 5. Varieties and Seasons 6. Weed Management.
Pearlmillet (Pennisetum glaucum), also known as cattail or bulrushmillet, is an important crop in arid regions of Africa and India. It dominates Sahelian agriculture and serves as a staple cereal diet to most West African population. Pearlmillet is endowed with greater ability to withstand harsh environment. The grain is comparatively more nutritious than other cereal grains.
In addition to its grain consumption as human food, it is also used as green fodder in India, Pakistan, southern USSR and Australia. It is used as a pasture crop in USA. Pearlmillet is the fifth important cereal crop of India after rice, wheat, maize and sorghum.
Origin and Distribution of Pearlmillet:
Bulk of evidence on the origin of pearlmillet comes from interpretations of present day distribution of the crop and its wild ancestors. Based on morphological diversity of the crop, it has been concluded that pearlmillet is native of Africa. There has been a great controversy over the specified region of Africa and the time period in which domestication took place.
Vavilov (1950) placed pearlmillet in the Ethiopian center of domestication, while Murdock (1959) placed its domestication by Mande people around Niger river. Still others placed its domestication in Sudan, Senegal and highlands of Sahara.
On global basis, pearlmillet is grown between 15°W and 90°E longitude and 5°S to 40°N latitude. It is primarily confined to drier continents consisting of southern Asia (mainly India), west, north and central Africa. It is grown successfully with rainfall varying from 50 to 1300 mm.
Around 500 mm rainfall during the crop season seems to be reasonable. It prefers a warm dry climate for its growth. An average temperature of 35°C is ideal for its growth and development. It can withstand drought but cannot grow well under waterlogging. It is often grown in poor soils but responds to good management.
Area and Production of Pearlmillet:
Globally, pearlmillet is cultivated in about 36 M ha with a total production around 30 M t and average productivity 800 kg ha-1. India is the largest producer of pearlmillet (8.9 M t) in the world. It is grown all over India, except Assam, northeastern states, Himachal Pradesh and Jammu and Kashmir.
Pearlmillet is largely confined to regions receiving 150 to 700 mm annual rainfall. Rajasthan (5.17 M ha), Maharashtra (0.87 M ha) and UP (0.81 M ha) account for about 85 per cent of the area and 66 per cent of the total production. Productivity is highest (1.78 t ha-1) in Haryana followed by UP (1.61 t ha-1) and TN (1.48 t ha-1).
Pearlmillet area in India, which was 9 M ha during 1950, increased to 13 M ha during 1970. The area, however, decreased to 9.6 M ha by 2006. There was significant increase in production from 2.6 M t in 1950 to 8.8 M t during 2009. The productivity increased form 288 kg ha-1 in 1950 to 1015 kg ha-1 in 2009.
Harvesting and Storage of Pearlmillet:
Harvesting and Threshing:
Maturity of ear heads is not uniform, especially in improved cultivars due to tillering habit of the crop. Seeds appear brown at maturely and possess 18 to 20 per cent moisture. At this stage the crop is harvested.
Traditional tall varieties with one or two tillers can be harvested at one time since tillers also mature simultaneously with the main shoot. In southern parts of the country, the plants with ear heads are cut just above ground level and spread uniformly on the soil.
The harvested crop with straw and ear heads intact is allowed to dry in the field for two to three days. After thorough drying, it is heaped for two to three months (up to January) till the weather is clear. The heap is removed and ear heads separated from the straw.
In the case of improved cultivars, with profuse tillering, the ear heads are harvested over a period as and when they mature. Usually around 70 per cent ear heads are harvested during the first harvest and the remaining in two or three harvests. After harvesting all the ear heads, the stover is harvested and left in the field for drying until it is transported to desired place.
The ear heads are sun dried for two to three days and threshed under the feet of cattle or tractor. Beating the ear heads by wooden sticks to separate grain is also followed. After threshing, the grain is separated from the chaff by winnowing, utilising the breeze to blow away the chaff.
Winnowing machine can also be used to clean grain from chaff. After winnowing and clearing, the grain is thoroughly dried in hot sun by spreading on dry floor and stirring it frequently.
Storage:
Pearlmillet grain should be dried to around 12 per cent moisture content for safe storage. Pearlmillet grain can be stored following the methods discussed under sorghum. Major storage insect pests are rice weevil, lesser grain borer and red flour beetle.
When damage by storage pests is expected, fumigate with any of the following:
1. Aluminum Phosphide at one tablet (3 g) 1000-1 kg seed.
2. EDCT mixture at 1.0 1 2000-1 kg seed.
3. EDB at 3 ml 100-1 kg seed for small-scale fumigation.
Water Management for Pearlmillet:
Pearlmillet is mostly a rainfed crop. Only around 4 per cent of the total area is under irrigation in Gujarat, Punjab, Maharashtra, Tamil Nadu and Andhra Pradesh. Soil and water conservation practices, therefore, assume significance in rainfed pearlmillet cultivation.
Moisture Conservation:
Antitranspirants and reflectants may minimise the water loss due to transpiration. However, practical problems limit their use under field conditions. Straw and plastic mulches are effective in reducing evaporation losses. However, availability and cost limit their use. Agronomic measures of soil and moisture conservation appear to be the only practical solutions.
Deep ploughing to increase rainwater infiltration into the soil, broad beds and furrows to minimise surface runoff and application of bulky organic manures to improve moisture holding capacity of soil appears to be practical solutions to minimise the runoff losses leading to moisture conservation.
Scheduling Irrigation:
Summer irrigated pearlmillet require six irrigations for high yield as indicated below:
1. Transplanting,
2. A week after transplanting (establishment),
3. Three weeks after planting (tillering),
4. Panicle initiation,
5. Flowering, and
6. Grain development.
Flowering and grain developmental stages are most sensitive to soil moisture stress. Under conditions of limited irrigation water, a minimum of three irrigations are necessary for economic grain yield: first irrigation for transplanting, second at tillering and the third at 50 per cent flowering.
Irrigation can be scheduled at 50 per cent DASM during moisture sensitive stages and at 75 per cent during other stages. An IW/CPE ratio of 0.6 appears to be ideal for optimum yield and high water use efficiency.
The crop is usually irrigated following check basin method of irrigation. Furrow irrigation reduces irrigation requirement. Crop water requirement of pearlmillet ranges from 450 to 550 mm depending on the agroclimatic conditions under which the crop is grown.
Varieties and Seasons of Pearlmillet:
Pearlmillet is a cross pollinating crop and its genetic improvement has been though conventional breeding for developing composites, synthetics and hybrids. Use of cytoplasmic genetic male sterility and recent techniques of population improvement along with tissue culture techniques have indicated great scope for genetic upgradation in the pearlmillet.
Varieties:
Several varieties evolved earlier to development of hybrids are still under cultivation, especially under rainfed conditions due to their adaptability, resistance to major pests and diseases and yield stability. Important among them are Co 1 to Co 5, K 1 and K 3 in Tamil Nadu, AKP 1 and AKP 2 in Andhra Pradesh, Bajra 207, L 17, Baroda and Babapuri in Gujarat and Maharashtra, RSK and RSJ in Rajasthan, T 55, S 350 and S 530 in Punjab and Uttar Pradesh.
In the pearlmillet hybrid development programme, first set of single cross hybrids (HB 1 to HB 5) using Tift 23A male sterility system revolutionaries the pearlmillet production. This was followed by the development of many other hybrids involving new versions of Tift 23 A that included BJ 104 and BK 560. These two become very popular across the country.
Hybrid programme received a setback in 1970s due to breakdown of resistance to downy mildew, primarily because of genetic vulnerability of CMS lines having the same cytoplasm (Tift 23A). Concerted efforts were made on genetic diversification of male sterile lines and incorporation of downy mildew resistance. Hybrids CMH 451 and Pusa 23 across the country and Sharada in Maharashtra and HHB 67 in Haryana and Rajasthan became popular.
Susceptibility of hybrids to downy mildew led to emphasis on population improvement programme and a number of open pollinated verities were developed. Improved cultivars recommended for different states have been given in Table 6.1.
Seasons:
Most of the cultivars grown in India are relatively photoinsesitive compared with West African material, which is very photosensitive and tall. Most of the pearlmillet is confined to monsoon period as rainfed crop.
Different seasons in which it is grown in the country are:
Kharif:
June-July in Karnataka, Maharashtra, Uttar Pradesh, Andhra Pradesh and Gujarat. July in Haryana, Punjab, Madhya Pradesh and Rajasthan.
Rabi:
September-October in Deccan tract and Tamil Nadu.
Summer:
As an irrigated crop, it is planted during January-February in Tamil Nadu, Karnataka, Punjab, Gujarat and Andhra Pradesh.
Optimum Time of Seeding:
It is an established fact that almost all the rainfed cereals perform better when seeded early with the onset of monsoon and pearlmillet is not an exception. Many experiments have been conducted in different pearlmillet growing regions on optimum time of sowing the pearlmillet.
First half of July is optimum time for sowing around New Delhi. Grain yield decreased by 40 to 80 kg ha-1 day-1 with delay in sowing rainfed pearlmillet due to poor crop establishment, poor grain setting and incidence of downy mildew.
Delayed seeding beyond July 20 resulted in low yield due to downy mildew and ergot diseases at several places in north India. Seeding beyond third week of July leads to poor yield under north and northwestern India.
Seeding the pearlmillet during second fortnight of June appears ideal for rainfed crop on light soils of Andhra Pradesh and adjoining sates of Tamil Nadu and Karnataka. Flowering and grain development coincide with heavy rains during October if the sowings are delayed up to middle of July leading to uneconomic grain yield. Irrigated pearlmillet suits well in intensive irrigated cropping systems due to its shorter duration and suitability for transplantation.
In southern parts of the country, it is grown in summer after rabi rice. Results of experiments indicated that pearlmillet could be transplanted up to March third week without significant reduction in yield. Yield difference due to transplanting in first or third week of March were marginal.
At all the dates of planting, pearlmillet sown by drilling recorded lowest grain yields compared with transplanted crop. Differences due to planting 20, 25 and 30 days seeding were marginal.
Weed Management of Pearlmillet:
Like sorghum, pearlmillet is rainfed crop in arid and semiarid regions. Weed species of pearlmillet are the same as that in rainfed sorghum crop. Weed competition is acute during early stages of pearlmillet when the crop growth is relatively slow. Critical period of weed competition is up to 35 days after seeding. Instances of grain yield loss up to 60 per cent due to unchecked weed growth are common.
Cultural Management:
Pearlmillet is usually a row crop during monsoon period with row spacing varying from 30 to 45 cm. As such, local inter-cultivation implements can be used for minimising weed growth. Weeds within the row can be removed by hand weeding.
Two intercultivations, 15 and 30 days after seedling emergence with one hand weeding around 20 or 35 days after seeding is adequate to minimise the losses due to weeds. In situations where inter-cultivation and manual weeding is not possible, use of herbicides is the only option for weed control.
Use of Herbicides:
PRE herbicides:
Atrazine (0.5-1.0)
Simazine (1.0-1.5)
Pendimethalin (0.75-1.5)
Tebutryn (1.0-2.0) for light soils
Propachlor (1.0-2.0) for light soils
Norea (1.0-2.0) for heavy soils
Fluometuron (1.0-1.5) for heavy soils
PRE Pendimethalin gives good preventive control of a wide spectrum of weeds without affecting pearlmillet. A follow up of POST 2, 4 -DEE (0.25-0.5) controls most of the late emerging broadleaf weeds and some annual grasses. As pearlmillet is sensitive to most herbicides, mixing a safener could increase the margin of selectivity to them.
Package of Production Practices:
Pearlmillet is, usually, a rainfed crop during monsoon. To a small extent, it is intensively cultivated as irrigated crop during rabi/summer.
Tillage:
1. Deep summer ploughing once in 2-3 years aids in perennial weed management besides soil moisture conservation for a rainfed crop.
2. Two to three ploughings for a rainfed crop, commencing with onset of monsoon, followed by harrowing for drilling the seed.
3. Two to three ploughings followed by levelling and planking for forming beds and channels for irrigated crop.
Recommended Cultivars for AP:
1. Hybrids:
ICMH 451, GHB 558, Nandi 35, PAC 903.
2. Varieties:
Ananth, ICMV 221, ICTP 8203, WCC 75.
Seeds and Seeding:
1. Optimum seeding time for kharif rainfed pearlmillet is early-June and for summer irrigated crop, January-February.
2. Recommended seed rate is 5 kg ha-1 for drilling under rainfed conditions and 3 kg for raising nursery for an irrigated crop.
3. Spacing for drilling is 30 x 10 to 45 x 8-12 cm and drilling depth around 5-6 cm.
4. Twenty one to thirty days old seedling are transplanted on the sides of ridges with a spacing of 45 x 20 cm
Fertiliser Schedule:
1. Recommended fertiliser schedule for rainfed crop in AP is FYM at 10 t ha-1 + 60 N along with 30 P2 O5 and 20 K2 O kg ha-1.
2. For rainfed crop, full dose of P and K and half of the N should be applied at seeding by placement/drilling. If the rainfall is adequate at knee-height stage, the remaining half of N can be applied.
3. For irrigated crop in AP, recommended schedule is FYM at 10 t ha-1 + 100-120 N along with 50 P2 O5 and 30 K2 O kg ha-1.
4. For irrigated crop, N should be applied in three equal splits at planting, 3 weeks after planting and 6 weeks after planting by placement.
5. Soil application of zinc sulphate at 25 kg ha-1, if necessary, at sowing for irrigated crop in intensive cropping systems.
Water Management:
1. Two most critical states for irrigation are flowering and grain development.
2. Six irrigations (transplanting, establishment, tillering, PI. flowering and grain development) are optimum for high yield.
3. If water is adequate for only three irrigations, it should be applied for transplanting, at tillering and at flowering stages.
4. Waterlogging should be avoided, particularly during seedling establishment and flowering stages.
Weed Management:
1. Critical period of weed competition is up to 35 DAS.
2. One or two timely intercultivations appear to be relatively more economical than herbicide use, especially under rainfed situations.
3. Atrazine (0.5-0.75 kg ha-1) is effective on broad spectrum of weeds.
4. PRE Pendimethalin (0.75 to 1.5 kg) followed by POST 2,4-DEE (0.25 to 0.50 kg) controls most of the weeds in pearlmillet.
5. Integrated weed management involving land preparation, timely intercultivation and herbicides appears to be economical under irrigation.