Everything you need to learn about sorghum cultivation, harvest and growth.
Introduction to Sorghum (Jowar):
Sorghum was grown in Egypt prior to 2200 B. C. and since then has been an important crop in that country. It is believed to have originated in Africa and Asia. It was cultivated in India and China at a very early date, the former being one of the leading countries now in respect of its production.
The crop is very important, both as food and fodder, in dry areas. It is widely cultivated in North and Central America, India, Pakistan, South America, USSR and Europe. The total annual area under sorghum in India varies from 17 to 18 million hectares and the range of annual production of grains in the country is from 10 to 11 million tonnes.
The major sorghum-growing states in India are Maharashtra, Karnataka, AP, MP, Gujarat, Rajasthan and Tamil Nadu. The crop is also grown in Bundelkhand area in UP. Certain other states also grow sorghum for fodder, but only on a limited scale.
Sorghum (Sorghum vulgare Pers.) belongs to the family Gramineae. Stems are erect and solid, 0.9 – 4.50 m high. Internodes short at the base, longer above; the terminal internode, which ends in the head, is the longest of all. Foliage leaves vary in different varieties. Leaf sheaths long with membranous margins.
Ligule short membranous and fringed. Leaf blades very similar to those of maize plant, but more erect. Inflorescence is somewhat compact panicle except in certain types. The main axis varies in length. All forms usually hairy at the nodes. Forms with long internodes tend to be more glabrous than those with shorter ones.
Lateral branches develop at the nodes. Each lateral may rebranch and branches of the -third order may form, ultimate branchlets bearing one to several paired spikelets. Spikelets usually occur in pairs on terminal racemes, except towards the tip, where they may occur in threes.
When the spikelets are paired, one is sessile and perfect, the other pedicelled and staminate. When in three, one sessile and perfect, the other is pedicilled and staminate; or at times, one staminate and the others perfect. Fertile spikelets relatively large; the shape may be ovate, oval, elliptical or obovate.
Each fertile spikelet has 2 glumes, about equal in length, one outer and another inner; both nerved. At maturity, they may be from half to two- thirds the length of the seed; at times, equaling the seed-length. Within the glumes, two florets present, the lower sterile and the upper perfect.
In the lower floret, only lemma present, which is broad, usually pubescent and membranous. The perfect floret has a membranous, hairy lemma, two-cleft at the apex, an awn arising in the cleft. Palea is small and thin. Lodicules two is short and broad. Stamens 3 ovary with 2 long styles, each ending in a short, brushy stigma. The mature grains vary in shape; may be globular, pear-shaped or flattened. The grain-colour is also variable. A well-developed panicle of sorghum may contain about 2,000 seeds.
Sorghums are generally 95 per cent self-pollinated in the field. They are, however, reported to cross readily with other varieties of sorghum or Sudan grass and Johnson grass.
Climate and Soil Required for Sorghum Growing:
Sorghum is a hardy crop and it withstands hazards of climate better than other kharif crops. It does well in arid areas and also in certain humid areas. It can grow successfully in a wide range of temperature, varying from 15.5°C to 40.5°C, with an annual rainfall of 35 to 150 cm.
The average rainfall in the sorghum belt generally ranges from 40 to 100 cm, which is usually received between the last week of June and the first week of October in most parts of India. The crop is grown in both kharif and Rabi seasons. The rabi jowar occupies 36-38 per cent of the total area under the crop.
Sorghum is grown in India in a wide range of soil types. Medium and deep black soils are very suitable for growing it. The Rabi sorghums are grown exclusively in black cotton soils, whereas the kharif sorghums are grown in light soils also, though on a small scale. A soil pH range of 7 to 8 is quite suitable for the crop. For successful cultivation of sorghum, the soil must be well drained and free from too much of salts.
A two-year rotation of jowar-cotton is very common during kharif in the Deccan area and also in central plateau, whereas during Rabi, jowar-cotton, jowar-gram or jowar-jowar rotations are common. Changes may be made in different areas in the rotations to be followed.
Mixed cropping of jowar-arhar is very common. During kharif, jowar is grown mixed with mung, urid, cowpea, bajra and other cereals, vegetables, etc., in certain areas. Jowar and safflower are commonly mixed during Rabi. With the availability of short-duration varieties of jowar, the practice of multiple cropping is now in vogue even under rain-fed conditions in areas, where the rainfall is assured.
Cultivation of Sorghum:
The land is prepared well with ploughs or blade harrows. Very little farm yard manure is generally applied. For grain purposes, 12.5 kg of seed per hectare is necessary. Seeds are sown with a seed-drill in rows, 30-45 cm apart. Intercultural operations are done with bullock-drawn implements. While weeds are a problem in red soils in kharif, they are not quite serious in black soils.
Manuring and Fertilization:
For raising a good crop of jowar, manuring is essential. In rain-fed areas, 37.5 kg each of nitrogen and phosphate and 35 kg of potash per hectare may be applied as the first dose, at the time of sowing. After a month, nitrogen is applied again at the rate of 37.5 kg per hectare. In irrigated areas, 57 to 68 kg of nitrogen, 62.5 kg of phosphate and 35 kg potash per hectare may be applied as the first dose, which may be followed by the second dose of nitrogen at the rate of 57 to 68 kg, 30 to 40 days after sowing.
Harvesting and Yield:
The local varieties mature in 130-150 days, whereas improved varieties and hybrids mature in 100-120 days. Harvesting and threshing are done manually. Threshing may sometimes be done with the help of bullocks. Threshing with the help of a tractor or a power-operated thresher is not very common. The grain is dried in the sun and stored.
While the average yields of grain in India are low and are around 500 kg per hectare, the yields of high-yielding hybrids and varieties range between 2,000 and 3,000 kg under average conditions. Much higher yields of 6,000-7,000 kg have been obtained under optimal conditions.
Uses of Sorghum:
The grain is used primarily as human food. It is either cooked as rice, or roti or bhakri (unleavened bread) is made of it. The grain is also malted or popped. Besides, various other local preparations are made. The stem and leaves, both green and dry, are considered very important as fodder for cattle throughout the country. Although there is enough scope, grain sorghum is not now used widely as a feed for cattle, poultry ration and other industrial purposes.
Varieties of Sorghum:
A wide range of variability is exhibited by Indian sorghums in respect of duration and grain quality. Most of the improved varieties now available have been developed by pure line selection in local varieties. Inter-varietal hybridization has also been resorted to and this has led to the combination of existing yield levels with good forage quality.
Some of the varieties developed during the early period, which are still under cultivation, are the Co-series of Tamil Nadu; the Nandyal, Guntur and Ankapalle series of AP; the PJ selections (kharif and rabi), Saoner, Ramkel, Aispuri, Maldandis and Dagadi (compact- head) selections of Maharashtra; the Bilichigan, Kanki Nandyal, Hagari, Fulgar white, Fulgar yellow, and Yenigar varieties of Karnataka; Budhperio, Sundhia and Chasatio of Gujarat; the selections of Gwalior and Indore of MP; RS selections of Rajasthan and also a few others.
Development of commercial hybrids began in 1962. Equal emphasis is now being laid on hybrid as well as on true-breeding varieties. Eight hybrids, CSH-1 to CSH-8, and seven high-yielding varieties, CSV-1 to CSV-7, were released for large-scale cultivation some years ago. Subsequently, other true-breeding varieties and hybrids have been released.
Some of the hybrids and varieties now recommended for different states are indicated below:
Diseases of Sorghum:
The diseases which, commonly attack jowar, are:
(i) Downy mildew caused by Sclerospora sorghi, which can be controlled by seed – dressing with Ridomil 25 and by growing resistant varieties.
(ii) Grain smut caused by Sphacelotheca sorghi, which can be controlled by treating the seed with sulphur or Agrosan GN before sowing @ 5 g/kg and 2 g/kg respectively.
(iii) Loose smut caused by Sphacelotheca cruenta, which can be controlled by treating the seed with Agrosan GN before sowing @ 2 g/kg.
(iv) Rust caused by Puccinia purpurea, which can be controlled by growing resistant varieties and by spraying 0.2% Dithane M 15 or by dusting finely divided sulphur.
(v) Bed leaf spot caused by Colletotrichum graminicola, which can be controlled by growing resistant varieties, practising crop rotation and improving soil fertility.
(vi) Ascochyta leaf spot caused by Ascochyta sorghina, which can be controlled by growing resistant varieties, practising crop rotation and improving soil fertility.
(vii) Leaf stripe caused by Pseudomonas sorghi-cola, for which no control measure is known.
(viii) Chlorosis caused by virus, for which no control measure is known.
(ix) Head smut caused by Sphacelotheca reiliana, which can be controlled by treating the seed with Agrosan GN @ 2 g/kg, practising crop rotation and burning smutted ears.
Insect Pests of Sorghum:
Some of the common insect pests of jowar are:
(i) Shoot fly (Atherigona soccata), which can be controlled by adjusting the sowing date, increasing the seed-rate, uprooting and destroying infested seedlings, treating the seed with Carbofuran (20 :1) or by applying 3% Carbofuran, 5% Disulfoton or 10% Phorate granules.
(ii) Stem borers (Chilo zonellus), which can be controlled by ploughing and destroying all the stubbles after harvest, applying Endosulfan or Carbaryl granules or spraying Lindane.
(iii) Sorghum midge (Contarinia sorghicola), which can be controlled by burning the panicle residue and chaff obtained after threshing of grain in order to destroy the larvae, by adopting a uniform date of sowing and by applying Endosulfan or Carbaryl or Lindane sprays or dusts.
(iv) Aphids (Aphis sacchari and Rhopalosiphum maidis), which can be controlled by spraying 0.02% Phosphamidon, 0.01% Diazinon, Methyldemeton or Dimethoate.
(v) Cut worms (Agrotis ipsilon and A. flammatra), which can be controlled by dusting 10% BHC on the soil around the plants.
(vi) Hairy caterpillars (Amsacta moorei and Estigmene lactinae), which can be controlled by dusting 10% BHC.
(vii) Mites (Oligonychus indicus), which can be controlled by dusting sulphur or spraying 0.05% wettable sulphur.