sorghum crop production technology AGRON 211

Crop production technology AGRON 211

1. 1 Sorghum ( Sorghum bicolor (L.) Moench )

2. Common name: S orghum, Jowar (Hindi), Great millet Vernacular names: Jwari (Marathi), Juar (Bengali, Gujarati), Jola (Kannada), Cholam (Malayalam, Tamil), Janha (Oriya), Jonnalu (Telugu). Other names: Milo, Chari Fourth food grains of the world. Ranks third in the major food grain crops in India. Millions of people in Africa and Asia depend on sorghum as the staple food. Sorghum is also used as fodder for livestock. Sorghum grain contains about 10-12% proteins, 3% fat and 70% carbohydrates. Therefore, it can satisfactorily replace other grains in feeding programme for dairy cattle, poultry and swine. Over 55% of grain produced globally is used for human consumption in the form of flat breads and porridges (thick or thin) and about 33% of grain used in feeding livestock. Jowar is used as human food and animal feed. Jowar is used as fodder for animals. Chopped green stems and foliage are used to prepare hay or silage and also as pasture crop. Sweet sorghum & pop sorghum are perched and consumed by human beings. S orghum flour is used for preparation of roti. It is also used in breweries to prepare alcohol and malting purposes. S orghum cake can also be prepared from fermented dough. Sweet sorghums are used to prepare syrups, biscuit making in bakeries. Left over stubbles are used as a source of fuel. Tribals eat sorghum grains and sweet stems containing 10% sugar. "Vani jowar" is a speciality of south Gujarat which is eaten under green perched conditions. Jowar dhani i.e. pop sorghum is very popular among children. Grain is sometimes fed to cattle, poultry and swines besides being used by human beings. Sorghum ( Sorghum bicolor (L.) Moench ); Family- Poaceae 2

3. Origin Sorghum is considered to be originated in Northern Africa or at the Egyptian-Sudanese border 5,000-8,000 years ago. Indian sub-continent is its secondary centre of origin, where it is cultivated since 4,500 years. After evolution from wild races of Africa, self seeding ability was lost. The date of arrival of cultivated sorghum in India is uncertain, but probably it was brought to India from Africa by visitors and merchants. East and Central Africa (Ethiopia/ Sudan) is regarded as the place of origin of sorghum because of the greatest diversity of types grown in that region. 3 Classification Three species of sorghum have been recognized Sorghum halepense (L.) Pers .; Sorghum propinquum ( Kunth .) Hitche ; and Sorghum bicolor . The first two species are wild. S. bicolor is further divided into 3 sub species viz., ssp. bicolor , ssp. Drummondii and verticilliflorum . The former one is cultivated and the latter two are annual weedy types. Harlen and de Wet (1972) classified genus sorghum based on spikelet types into 5 basic races ( bicolor , guinea, caudatum , kafir and durra) and ten hybrid races (guinea- bicolor , caudatum-bicolor , kafir- bicolor , durra- bicolor , guinea- caudatum , guinea-kafir, guinea-durra, kafir caudatum , durra- caudatum and kafir durra). ssp bicolor is the most primitive and low yielding one. ssp guineais cultivated in West Africa in areas with >1,000 mm rainfall and is low yielding. ssp. caudatum is dominant in Sudan, Chad, Nigeria and Uganda. ssp. kafir is cultivated in Northern Nigeria and Ghana. It is high yielding one and originated recently.

4. Area and distribution Globally sorghum is cultivated over an area of about 42.7 million ha with a production of about 58.7 million tones. Among the 99 sorghum growing countries of world, India ranks first in terms of production followed by USA, Nigeria, Sudan, Ethiopia and Burkina Faso. In India sorghum is grown over an area of 4.24 M ha with total production of 4.78 mt and productivity 1128 kg/ha (2020-21). Sorghum ranks third in the major foodgrain crops in India, whereas it is the fourth foodgrains of the world. Maharastra is the leading state with highest area (1.94 mha ) and production (1.76 mt ) while Andra Pradesh is first in average productivity with 30.70 q/ha against national average of 11.28 q/ha. In rajasthan it is grown on 0.56 m ha with 0.59 mt and av. productivity 10.50 q/ha (2020-21). Major growing disstricts are Ajmer, Nagur , Bharatpur , Dholpur , tonk , Pali, Bhilwara. In India 10.1% area under irrigated condition while, in Rajasthan only 0.50% (2018-19). It is most important cereal crop in India. It stands second in area (next to rice), but third in production after rice and wheat. It is cultivated primarily as a crop both during kharif and rabi and is one of the main reasons for low average yields. It is mostly grow n in marginal lands which do not suit for wheat and maize. It is one of the major food crops of the world (wheat, rice, maize and jowar ). Millions of people in Africa and Asia depend on sorghum as their staple food. 4

5. 5 Sorghum is able to tolerate drought better than most other grain crops and can be attributed to: An exceptionally well developed and finely branched root system, which is very efficient in the absorption of water; It has a small leaf area per plant, which limits transpiration; The leaves fold up more efficiently during warm, dry conditions than that of maize; It has an effective transpiration ratio of 1:310, as the plant uses only 310 parts of water to produce one part of dry matter, compared to a ratio of 1:400 for maize; The epidermis of the leaf is corky and covered with a waxy layer, which protects the plant form desiccation; The stomata close rapidly to limit water loss; During dry periods, sorghum has the ability to remain in a virtually dormant stage and resume growth as soon as conditions become favourable . Even though the main stem can die, side shoots can develop and form seed when the water supply improves. Growth stages of a 9-day-old sorghum plant

6. Climatic requirement It is a short day C4 plant . Sorghum requires warm climate but can be grown under a wide range of climatic conditions. The plant can tolerate high temperatures throughout their life-cycle better than any other cereal crop. It can tolerate drought conditions very well because it remains dormant during moisture stress conditions but resumes growth when favourable conditions reappear. It has high resistance to desiccation, low transpiration ratio and a large number of fibrous roots. It can also tolerate water logging conditions better than any other cereal except rice. Therefore, it can be grown successfully in areas having average annual rainfall between 40 and 100 cm. The minimum temperature for germination of sorghum seed is 7-10 o C. At a temperature of 15ºC, 80 % of seed germinate within 10 to 12 days. It needs 26-30 o C temperature for its optimum growth. Though it can withstand temperatures up to 45 o C, but the lower temperatures (<8 o C) limit its cultivation owing to impaired flowering and pollination. Hence, its rabi cultivation is not possible in north India. In western and southern parts of the country it is grown also as a rabi crop. Temperatures below13 o C at blooming stage are detrimental to seed setting in rabi . Flowering is hastened by short days and delayed by long days. The time of heading in sorghum is influenced by temperature as well as photoperiod. It is grown from sea level to as high as 3,000 m elevation. Sorghum cultivation during kharif is declining in the country as prolonged rains at flowering stage aggravates grain mould incidence and the infected grains are unfit for human consumption. 6

7. Soil requirement Sorghum can be grown on wide range of soil provided good drainage facility. The soil should be loam and near neutral. In India, it is mainly grown in alfisols (red) and vertisols (black). These soils have pH ranging from 6.5 to 7.5 coupled with low N and P and rich in non-exchangeable potash. These soils are mostly found in Andhra Pradesh and Karnataka. Field preparation Sorghum requires a well prepared seed bed for good crop establishment. Proper tillage reduces weeds by killing the germinating seedlings and burying deep the weed seeds. Seed bed preparation are governed by local conditions such as weed intensity, moisture availability and soil erosion risks . The field is prepared by deep off-season ploughing every year in shallow to medium deep soils. Ploughing is required once in summer followed by 2-3 harrowings . Thereafter, around 8-10 tonnes of farm yard mannure (FYM) per ha need to be incorporated. Soil application of Phorate or Thimate @ 8-10 kg/ha is recommended at the time of sowing. This should be done soon after harvest of rabi crop in double cropped regions, immediately after cessation of west monsoon. The cloddy field also aids in moisture conservation by increased opportunity time for runoff. With the onset of monsoon, the field is ploughed or harrowed 2-3 times to break the clods followed by planking. In heavy soils prone to water logging, levelling is also done for easy drainage. There should be proper moisture at the time of sowing. 7

8. Sowing time Sowing of sorghum should be undertaken with the onset of monsoon. Dry sowing about one week in advance of monsoon ( firm forecast ) is also practiced in black cotton soils. It is mainly a kharif season crop in north India. In South India, it can be grown in kharif, rabi as well as summer seasons. In kharif under rainfed situations, the onset of monsoon is the single most factors deciding sowing time. Last week of June to first week of July is the optimum time of sowing for kharif and rainy season crop (25 June to 10 July) . However, under irrigated conditions, the crop establishment before onset of monsoon is ideal. Thus 1-2 weeks advance sowings before monsoon are adopted. Too early or delayed sowings are not good as the flowering time may coincide with rains leading to grain mould incidence in the former case and moisture stress in the later. Rabi sorghum is cultivated in the states of Maharashtra and Karnataka. The optimum time of sowing of rabi sorghum under rainfed conditions is second fortnight of September to mid-October . Under irrigated conditions sowings can be delayed and second week of October is the optimum time. For summer sowing the ideal time is 20 March to 10 April and April is the optimum sowing time for Sweet Sudan Grass . Planting time in rabi sorghum is dictated by (a) rainfall pattern in the monsoon season and moisture content of the soil at the time of planting; and (b) intensity of seedling pest, the “shoot fly”. Timely planting is of paramount importance in rabi. Planting too early invites very heavy infestation of shoot fly, and delay in planting results in yield reduction due to moisture stress at grain development stage. Planting around the middle of September is ideal. In case of moisture availability, the planting could be extended up to first week of October. 8

9. Seed rate and sowing method The optimum plant population depends upon the available moisture, soil fertility status and morphology of genotypes being cultivated. In kharif and irrigated rabi seasons, the optimum population varies from 1, 50,000 to 2,00,000 plants/ha. The optimum plant population recommended during kharif is 1,80,000 plants/ha. This can be achieved by using 8 ( 8-10) kg seed and planting at 45 cm x 12.5 cm or 60 cm X 9.5 cm ( 45 cm x 15 cm or 60 cm x 10 cm) In rabi season, under receding moisture conditions a plant population of 1,35,000 plants/hectare. However, under irrigated or assured soil moisture conditions, higher yields could be achieved with 1,80,000 plants /ha. A row spacing of 45 or 60 cm with plant to plant distance of 15 cm is optimum. A seed rate of 8 ( 8-10) kg/ha is sufficient. In north India, sorghum is sown either by broadcast or in rows behind the plough. The seeds of hybrids and improved varieties should always be sown in rows for obtaining higher yields. Sorghum is a tall growing crop, and to avoid mutual shading, sowing in sun rise and sun set direction is ideal. Under moisture limiting environments, paired row planting pattern has been found promising. The paired row planting systems include 30/60 cm and 45/90 cm. Treat the seed with 5 gm Imidacloprid 70 WS + 2 g Carbendazim (Bavistin) per kg of sorghum seed, or Thiomethoxam 3 gm/kg of seed. Seed treatment is essential to avoid major insect pest infestation and soil borne diseases. Thinning In rows, plants should be thinned out to maintain 15-20 cm plant to plant spacing at 2 stages. First thinning should be done 10-15 days after emergence and the second at 20-25 days after sowing. All diseased and insect infested plants should be removed in thinning.

10. 10 Sorghum-based Cropping systems: Intercropping: Sorghum intercropped with pigeon pea, sunflower, green gram or soybean has been found to be widely adopted by the farmers. The most ideal sorghum genotypes found suitable for intercropping are CSH 16, CSH 17 and CSH 18. Sorghum and pigeon pea are to be sown in the 2:1 row ratio keeping full normal population of sorghum. No additional fertilizers are required. In case of inter-cropping, spraying of weedicide/herbicide is not recommended . In some cases, the medium maturing sorghum genotypes such as CSH 16 and CSH 18 are also recommended for intercropping in 3:3 ratio. Another profitable intercropping system is sorghum and fodder cowpea in 2:2 row proportions. This system besides providing green fodder was also found improve soil fertility and in checking of weed growth. Sequence cropping: A sequence crop in rabi following sorghum in kharif was found to be profitable in those areas which receive rainfall above 700 mm and having moisture retentive medium to deep black soils. The most suitable and profitable crops are chick pea, safflower and mustard in most of the situations. The following techniques are suggested to make sequence cropping system economical and feasible . a) Kharif sorghum crop should be harvested at its physiological maturity to gain about one weeks time in planting the winter crop. b) Practice of minimum tillage needs to be adopted. It helps to gain time, minimizes land preparatory costs and prevents soil moisture loss. c) Sowing of winter crop should be drilled without much opening of the soil. d ) Inter cultivation should be done at appropriate time to minimize weeds and soil water loss. North India: Sorghum-wheat, Sorghum-wheat-moong, Sorghum-gram, Sorghum-potato-wheat, Sorghum-Raya, Sorghum-potato/rape-wheat / tobacco, Sorghum-cotton-groundnut, Sorghum-wheat-cowpea/ pearlmillet , Sorghum-wheat- greengram , Sorghum-pea/oat/berseem, Sorghum-gram or barley and Sorghum-lentil South India: Sorghum-cotton, Sorghum-Sorghum( rabi ), Sorghum-tobacco , Groundnut- Sorghum ( rabi ) and Sorghum-ragi-groundnut

11. Fertilizer requirement Sorghum is an exhaustive crop, but needs moderate fertilizer application owing to its moisture limiting conditions. Fertilizer requirement of hybrid/composite varieties of sorghum is higher than desi cultivars. In rainfed crop, 10 t/ha of FYM with 40-60 kg N/ha and 20-30 kg P 2 O 5 /ha is applied as basal. Under irrigated conditions, the crop should receive 80-100 kg N and 30-40 kg P2O5/ha. All P along with 50% N is applied as basal at the time of sowing. Rest 50% N is top-dressed by band placement 30-40 days after sowing at flower primordial initiation stage. For sweet sudan grass apply 25 kg nitrogen/ha after each cut. Soil application of 25 kg zinc sulphate once in 3 years or foliar spray (2 times) of 0.2% zinc sulphate is promising in zinc deficient soils. In case of iron deficiency, foliar spray (twice) of 0.1% ferrous sulphate is recommended. Kharif (Rainy season): For light soils and low rainfall areas: Apply 30 kg N, 30 kg P2O5 and 20 kg K2O per ha at the time of sowing. Apply another 30 kg N at 30-35 days after sowing (DAS). For medium-deep soils and moderate to high rainfall areas: Apply 40 kg N, 40 kg P2O5 and 40 kg K2O per ha at the time of sowing. Apply another 40 kg N at 30 DAS. Rabi (Post rainy season): For rainfed (shallow to medium soil) conditions, apply 40:20:00 kg of NPK/ha as basal dose. For rainfed (deep soil) conditions , apply 60:30:00 kg NPK/ha as basal. For irrigated conditions apply 80:40:40 kg of NPK/ha (N in two equal splits 50% as basal and 50% at 30-35 DAS, full P and K at time of sowing). 11

12. Water management It is predominantly grown as rainfed crop in kharif and on conserved moisture in rabi . The water requirement of sorghum varies from 30-50 cm ( kharif and rabi ) to 60-70 cm (summer). Summer jowar is grown exclusively under irrigation. Depending upon availability of water resources for irrigation, jowar is provided with protective irrigation in kharif and is grown as irrigated crop in rabi . Early sown crop (March-June) generally requires 4-5 irrigations. However, June or July sown crop requires 1 or 2 irrigation depending upon rainfall. The peak water needs of jowar crop is at booting to seed setting stage. Under adequate water supply conditions of rabi and summer, irrigation should be given at all these critical stages. Irrigation is needed at 5 stages of the crop i.e. 1. Germination (at the time of sowing) 2. Knee high stage (30-35 DAS) 3. Flag leaf stage (50-55DAS) 4. Flowering (70-75 DAS) 5. Grain formation stage (100-105DAS) If water is available for 2 irrigations only, these should be applied at flower primordial initiation and flowering stages. In case of limited availability of irrigation water, it can be restricted to one irrigation and it should be at flower primordial stage or boot leaf stage depending on the soil moisture situation. 12

13. Weed management Weeds simultaneously germinate in the crop sown under kharif rainfed conditions. The initial 30-45 days after sowing is the critical period of crop-weed competition. The crop should be kept weed free during this period. This is achieved by manual weeding and hoeing in rabi and zaid seasons. During kharif season, intermittent rains may not permit weeding and hoeing. Weeds may cause 20-60% reduction in yield, if not controlled at right time. During kharif season both grassy and broad-leaved weeds grow with sorghum crop. These are: Echinochloa colonum , E. crusgalli ( sawank ), Dactyloctenium aegypticum ( makra ), E. leusineindica ( kodo ), Setaria glauca (bandar- bandri ), Cyperus rotundus ( motha ), Sorghumhalepanse ( banchari ), Cynodon dactylon (doob), and Phragnutes kakta ( narkul ). Weeds should be removed with the help of hand hoe in 3 and 5 week old crop. Atrazine @ 1.0 kg/ha in 800-1000 litres of water as pre-emergence just after sowing could successfully control the weeds. There should be enough moisture in the soil at the time of spraying. Intercropping with cowpea has also been found effective in weed management. The integration of above herbicides with one hand weeding or hoeing 35-40 DAS may effectively control most of the weeds. If root parasitic weed Striga asiatia (L.) Kuntze or witchweed ( rooiblom ) can be controlled by hand pulling when population is less, otherwise , sodium salt of 2,4-D should be applied as post-mergence @ 1 kg/ha between 20-60 DAS. 13

14. Disease management Downy mildew ( Sclerospora sorghi ): Infested seeding have pale yellow narrow leaves that are covered on both sides by soft white downy growth of fungus. The affected plants remain stunted and dry up permanently. For control seed treatment with Metalaxyl or Ridomil 25 WP @ 1g a.i. or Agrosan GN or Ceresan @ 4 g/ kg seed and spray of Dithane Z 78 (0.2%) or Ridomyl -MZ @ 3g/L water is recommended to reduce secondary infection. The diseased plants should be removed and buried into the soil. Anthracnose ( Cercospora sorghi ): The disease appears as small spots on leaves and lower parts of the plant, which spread upwards later on. The leaf spots are light brown at center and dark at the margins. Seed treatment with Agrosan GN @ 3 g/kg seed followed by spray of Zineb (0.2%) at 10 days interval starting from 35 DAS can control the disease. Grain smut: The affected grains are malformed, discoloured and contain black spore masses. This disease can be controlled by spray of Vitavax or Plantvax @ 0.2% to reduce the smut severity. Red leaf spot : Irregular, tan coloured spots with reddish brown margins appear on leaves. Improve soil fertility and eradicate Baru grass. 14

15. Insect management: Shoot fly is a major pest of the sorghum and infestation occurs during seedling stage up to one month. Maggot cut the growing point and feeds on the decaying tissues. The infestation results in withering and drying of the central leaf, giving a typical “dead-heart” symptom. Shoot fly attacks the crop from March to mid-May and mid-July to September. It is, therefore, desirable to sow the crop from mid-May to June. It can be managed by early sowing within 7 to10 days of the onset of monsoon and u se high seed rate (10%) @ 10 to 12 kg/ha in case of delayed sowing , remove plants with dead-hearts (formed by shoot fly as well as stem borer) at weekly interval, and destroy them. Intercropping of sorghum + redgram in 2:1 ratio should be followed. Seed treatment with Imidacloprid 70 WS@5ml/kg or Thiamethoxam 70 WS @ 3 g/kg of seed may also be used. Soil application of Carbofuran 3G granules @ 20 kg/ha in furrows at the time of sowing or spray cypermethrin 10 EC @ 0.02% coinciding with Shoot fly oviposition (7-14 days after germination) should be done at the seedlings stage. 15

16. 16 Stem borer is a major pest of sorghum and it attacks the crop from 2 nd week after germination until crop maturity. Irregular-shaped holes on the leaves are caused by the early instar larvae feeding in the whorl. Drying of central shoot giving “dead-heart” is observed and extensive stem tunneling is also found. Peduncle tunneling leads to breaking of peduncle, which results in complete or partial chaffy panicles. In young crop, growing shoot dries while in grown up crop; caterpillars found feeding inside the stem. For the control spray 1000 g carbaryl 50 WP in 500 litre water per hectare after 20 days of sowing and repeat spray 10 days after spray. Deep ploughing after harvest is essential.

17. 17 Fall armyworm (FAW; Spodoptera frugiperda (J. E. Smith)) is emerging as the most destructive pest of maize in India since its report in May 2018 in maize fields at the College of Agriculture, Shivamogga, Karnataka . Its rapid spread to more than 90% of maize-growing areas of diverse agro -ecologies of India within a span of 4 year presents a major challenge to smallholder maize farmers, maize-based industry, as well as food and nutritional security. FAW is a polyphagous pest feeding on over 100 recorded plant species belonging to 27 families. However, it pref ers plants from Gramineae family including many economically important plants such as maize, sorghum, millets, sugarcane, paddy, wheat etc. The young larvae ( Ist to IInd instar) scrape both of the leaves skeletonising the upper epidermis leaving silvery transparent membrane. The IIIrd instar larvae, the larvae enter the whorl and inflict ragged edged oblong holes on leaf lamina presenting ragged edged holes. Once the larvae reaches fifth instar it feeds voraciously causing extensive defoliation of the whorl. On an average 1-2 larvae were found in each whorl. General management measures • Deep ploughing of the field exposes the FAW larvae and pupae to sunlight and natural enemies. For synchronous planting sow the crop within the sowing window so that single stage of crop is available. • Deploy pheromone traps @ 12 traps / ha for monitoring the FAW . • Collect and destroy egg masses/ larvae during scouting. • Erect bird perches @ 25/ha. soon after sowing as it facilitates movement of insectivorous birds viz ., black drongo and swallows which predate on flying moths as well as caterpillars . Currently, in India, the Central Insecticide Board and Registration Committee (CIB and RC) has recommended the insecticides, namely chlorantraniliprole18.5 SC @ 0.4 ml/l, spinetoram 11.7 % SC @ 0.5 ml, thiamethoxam 12.6%+lambda cyhalothrin 9.5% ZC @0.25 ml/l for minimizing the damage in maize. The Gov- ernment of India ( GoI ) has recently recommended the use of cyantraniliprole 19.8% + thiamethoxam 19.8% FS @ 6 ml/kg seed as seed treatment against FAW.

18. 18 1. Cob damage 2. Scrapping 3. Shot hole 4. Whorl damage 5. Stem damage 6. Cob tip damage

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21. Harvesting and threshing The crop should be harvested immediately after maturity. There is no need to wait for stalk stand leaves to dry as the plants of hybrid sorghum appear green even after the crop maturity. The right time for harvest is when grains become hard and contain less than 25% moisture. Generally 2 methods of harvesting i.e. stalk cut and cutting of earheads by sickles are adopted. In case of stalk cut method, the plants are cut from near the ground level. The stalks are tied into bundles of convenient sizes and stacked on the threshing floor. After 2-3 days, the earheads are removed from the plants. In other method, earheads only are removed from the standing crop and collected at the threshing floor for threshing after 3-4 days of sun drying. Threshing of earheads is done either by beating them with sticks or by trampling under bullock feet. The later method is quicker and adopted by majority of farmers. Threshing is also done with the help of threshers. The threshed grain should be cleaned and dried in sun for 6-7 days to reduce the moisture content down to 10-12% for safe storage . 21

22. 22 Cyanide (sometimes called prussic acid) and nitrate can be present in various amounts in grain and forage sorghums. In hot and dry conditions, such as drought, these plants become stressed, causing them to accumulate these toxins. Fatalities can occur when ruminants graze sorghum crops or are fed sorghum hays containing excess levels of cyanide and or nitrate toxins. Cyanide poisoning from sorghum: Animals, especially ruminants, can suffer cyanide poisoning from eating plants that contain high levels of cyanogenic glycosides . All sorghums can accumulate cyanogenic glycosides and have the potential to poison stock, but some are safer than others. Inside the animal's rumen the plant cyanogenic glycoside is hydrolysed to release hydrogen cyanide. Cyanide prevents the release of oxygen from the red blood cells, starving the tissues of oxygen. Risk during the lifecycle of the crop: Cyanide-producing potential is present during any stage of the crop's lifecycle. The risk is higher when growing plants are stressed by: • wilting • crushing • droughts • frosts • trampling • hail damage • insect damage (grasshoppers and caterpillars). Therefore, stressed regrowth is considered the most dangerous—take care at this stage to avoid poisonin g. The lowest risk of cyanide accumulation is when plants are flowering and seeding. Safe levels of cyanide for cattle and sheep: There is a wide difference in cyanide accumulation in different plant varieties, for example, grain sorghums, and the sweet sorghum and delayed- flowering varieties, tend to have much higher cyanide levels than other varieties. Sorghum almum and Johnson grass ( Sorghum halepense ) are the most dangerous, while silk sorghum is generally one of the safes t. The cyanide concentration of plants is measured as mg/kg or ppm (parts per million) of hydrogen cyanide on a dry weight basis. Some common sorghum varieties have relatively high cyanide concentrations of between 400-900 mg/kg. However, as a general rule-of-thumb cyanide levels above 600 mg/kg are a risk to grazing stock but levels down to 200 mg/kg can still be a threat to very hungry animals. Hay made from hazardous sorghum forage will remain hazardous. Ensiling such material can decrease its cyanide potential, but actual levels in the end product should be checked before feeding it.

23. 23 Nitrate poisoning in sorghum: Nitrate can accumulate in many weed, crop and pasture plants (forage sorghum, grain sorghum, sudan grass hybrids and pearl millet). Plants accumulate nitrate when soil nitrate is high but conditions are not favourable for normal plant growth, which would normally allow the nitrate to be converted to plant protein. Nitrate in plants is converted to nitrite by bacteria present in the animal's rumen . The excess nitrate and nitrite is absorbed through the rumen wall into the bloodstream. Nitrite changes the normal red haemoglobin in blood cells to brown methaemoglobin that cannot carry oxygen. If more than 75% of haemoglobin is converted this prevents the blood from carrying enough oxygen, starving the tissues of oxygen, causing the animal to die. Factors that influence nitrate build-up: Nitrate build-up in plants depends on many factors but generally occurs where soil nitrate is high and the plants are not able to convert the nitrate to protein (reduced photosynthesis). High soil nitrate concentration can be due to: • nitrogen fertiliser application • high manure deposition • fallowing • drought. Nitrate build-up in plants can occur during: • drought and rain post drought • cloudy weather • cold weather • wilting • herbicide application • insect or fungal damage Most nitrate in plants is concentrated in stems and stalks. Toxic amounts of nitrate will persist in hay. Safe levels of nitrate for cattle and sheep: The nitrate concentration of plants is generally measured as per cent (%w/w) nitrate, expressed as potassium nitrate (KNO3) equivalent on a dry weight basis. Plants are regarded as hazardous to ruminants if they contain 1.5% or greater KNO3. Animals may become acclimatised to concentrations up to 3%, but any sudden increase in feed intake or the addition of supplements containing monensin can lead to poisoning.

24. 24 Rules for using sorghum crops for fodder : The following guidelines for using sorghum crops as fodder can help reduce the risk of cyanide and nitrate poisoning: • avoid grazing stressed plants or when regrowth is sprouting • delay grazing until plants are more than 45cm high for short varieties and 75cm high for tall varieties. Flowering plants or grain are less likely to poison stock • do not graze hungry stock. Animals are most likely to be poisoned if they eat large amounts in a short time • watch your stock closely in the first hour and monitor at least twice a day for the first few days • supplement stock with sulphur-containing licks or blocks or molasses (which is naturally rich in sulphur). Sorghums are low in sulphur and sulphur helps the liver to detoxify cyanide • test crops for cyanide and/or nitrate levels before using as fodder if in doubt about its safety • do not use crops that are unsafe to graze to make hay. Ensiling hazardous sorghum will reduce the cyanide content but the end product should be tested before use SORGHUM EFFECT: Sorghum is an exhaustive crop. It removes more amounts of nutrients. So, two exhaustive crops like sorghum and cotton should not follow each other. Instead pulse crop can follow sorghum. It was experienced that some of the succeeding crops to sorghum do not thrive well due to some toxic effect left over by the jowar crop. This can be counteracted by good manuring of the succeeding crop with FYM and by green manuring or crop rotation or sorghum mixed cropping.

25. 25 Drought mitigation through contingency planning Early onset of monsoon: Sowing with the onset of monsoon is recommended for assured high yields. Early onset of monsoon followed by a long gap: Repeated intercultivation operations like hoeing, weeding and mulching are suggested to conserve moisture. Under severe moisture stress, reduce the plant population by 2/3 by thinning for judicious use of moisture. Limited plant population assures normal growth of the crop. Delayed onset of monsoon: In case there is delay in monsoon by 2-3 weeks, short duration cultivars such as CSH 23 can be preferred. Increase seed rate to 1.5 times of the recommended rate and apply 20 Kg of Carbofuran or Phorate (3 g) granules in the seed rows before sowing to safe guard against the shoot fly attack. Other shoot fly control measures (spraying of Endosulfan 2ml/ litre of water after sowing ) can also be followed if soil application is not adopted. Prolonged monsoon and excessive rainfall at maturity: These situations at seed development stage are likely to cause heavy grain mold infestation. Harvesting of the crop at physiological maturity to avoid damage by grain mold alternatively spraying fungicidal mixture containing 0.3% Dithane M-45 three times at 10 days interval starting from 50% flowering onwards are recommended. Failure of monsoon: If monsoon fails after sowing of the crop, plant population should be reduced proportionately to 1/2 either by uprooting alternate plants or alternate rows. However, in case of partial failure and extremely delayed monsoon alternative crops like castor, Pearl millet and horse gram may be sown in light soils.

26. 26 Sweet sorghum - promising alternate biofuel crop Sweet sorghum similar to grain sorghum, but accumulate sugars (10-15%) in its stalks as in sugarcane . It is a potential alternative feedstock with less water and input requirement crop than those of sugarcane from which molasses is obtained. The bagasse after extraction of juice from sweet sorghum has higher calorific value and hence, can be used to generate power. Bagasse can also be used as animal fodder after suitable processing and also as a substrate for production of second-generation cellulosic ethanol. Biofuel include fuel derived from biomass conversion, as well as solid biomass, liquid fuels and various biogases. Some sweet sorghum lines yield juice about 78% of total plant biomass and contains soluble fermentable sugars from 15 to 23% (by comparison , sugarcane has 14–16%). The sugar is composed mainly of sucrose (70–80%), fructose and glucose. Sweet sorghum varieties and hybrids have the ability to produce extremely high stalk yields of up to 50 t/ha, with juice brix between 18% and 22% and 1.5 to 2.5 t/ha grain. Characteristics of sweet sorghum • High biomass productivity (45–80 t ha-1). • High Brix (soluble sugars) (16–20%). • Thick stems and juicy internodes with maintenance of stem juiciness until maturity. • Photo- and thermo-insensitivity so that it can be grown throughout the year and fit into diversified cropping systems. • Good digestibility of residues when used as forage or for lignocellulosic ethanol production. • Tolerance to mid-season and terminal drought. • High water and nitrogen-use efficiencies. • Grain yield ( 3.0–5.0 t ha-1).

27. 27 Improved production technology:- Sowing time: Kharif season crop (June-October): Sowing should be taken immediately after the onset of monsoon, preferably from second week of June to first week of July, depending on the onset of monsoon. Sow about three seed per hill by hand dibbling or planter at 5-cm deep. Please make sure that soil has fully charged with rainwater at least in the top 30 cm soil layer to ensure uniform germination. Rabi season crop (October–February): Planting should be carried out from last week of September to first week of November. The night temperatures should be above 15 ºC at the time of sowing. Summer season crop: Planting can be done from mid-January to end of May under irrigated condition. The night temperatures should be above 15 ºC at the time of sowing. Fertilizer management Total 80 kg N, 40 kg P2 O5, and 40 kg K2 O is recommended. Apply 50% N, full P2O5 and K2O at sowing as basal dose. Apply remaining 50% N as side-dress at two equal installments at about 25-30 DAS ( i.e. at final thinning) and at about 50-55 DAS after ascertaining the availability of soil moisture. Seed rate: 8 kg/ha (or 3 kg/acre) is recommended Spacing : Row to row distance of 60 cm; and plant to plant distance of 15 cm is recommended. Plant population: Population of 1.10 to 1.20 lakh plants per ha (40000 to 48000 plants per acre) is optimum for realizing maximum productivity. Raising sweet sorghum with excessive plant population than recommended will result in the production of thin stalks that will lodge due to heavy winds or rains . Tillering : Remove the side tillers (basal) manually, if they occur before 20-25 DAS from the base of the mother plant . Irrigate t he crop if the dry spell (drought) continues for more than 20 days on deep soils and more than15 days on medium/sandy loam soils especially at critical crop growth stages such as panicle initiation (35-40 DAS) and boot stages (55-65 DAS ). Maintain soil always at field capacity. Harvest the crop at about 40 days after flowering of the plants, i.e. at physiological maturity of grain where black spot appears on the grain at the lower end.

28. 28 Sorghum fodder Sorghum besides an important food crop of world is also valued for its fodder and stover . Sorghum fodder is suitable silage and hay making and thus can supplement the fodder supply during lean season. The dry stover forms important feeding stock for animals especially in dry areas. It is suitable for cultivation in areas that are too dry for maize. Geographic Distribution It is cultivated for fodder purpose in the country on over 2.6 m ha. Cultivation confined to mainly in the states of western Uttar Pradesh, Haryana, Punjab, Gujarat, Rajasthan and Delhi. It meets over 2 / 3 of the total forage demand of kharif seaso n. Soil and its Preparation Sorghum is grown on all types of soils, except sandy soils. Heavy soils should be well drained . It can tolerate moderate levels of salinity, and suitable pH ranges from 5.0-8.5. It does not require fine seedbed. Two-three harrowings are sufficient for seed-bed preparation (The land is prepared by 2-3 harrowings .

29. 29 A large number of single and multicut sorghum varieties have been evolved with 50-70 t/ha/year (season) green fodder yield. The varieties with less menace of leaf diseases and stem borers are ideal for fodder purpose. In north India, grain types are grown during kharif for fodder production. Varieties Fodder varieties of sorghum for different areas Variety Region Single cut PC-6, PC-9, PC-23, HC-171, HC 260, HC 308, Pro-Agro- chari , Jawahar Chari 6 For whole country ( early medium duration) HC-136, Raj chari-1, Raj chari-2, Haryana Chari, HJ-523, MFSH-3 Whole country (late varieties) Sl-44, MP Chari, UP chari-2 North India Pant chari-3, UP chari-1, Haryana chari-6, JS-3 UP, Andhra Pradesh, Tamil Nadu, MH Double cut Co-27 Tamil Nadu AS-16, GFS-1 Gujarat Multicut PCH-106, Punjab Sudex *, Pusa chari-23, Jawahar chari-69, Hara sona *, Pioneer-988, SSG-59-3 ( Meethi Sudan), MFSH-3, SPV-932 Whole country   Dual purpose ( grain & fodder)   CSV 15 CSH 13 As single cut for north-west India Single cut hybrid superior to HC 6  

30. 30 The characteristics of important varieties are given below. Single cut varieties Haryana chari (JS 73/53): A selection from germplasm collected from UP and released in 1975. It is susceptible to red leaf spot and stem borer. Green fodder yield is 30 t/ha. HC-136: A derivative of cross between 3214 x PJ 7R, released in 1981 for irrigated conditions. Low in HCN and tannin contents with green fodder yield of 58 t/ha. Tolerant to major diseases and insect pests. HC-171: A derivative of cross between SPV-8X x IS-4776, released in 1984 for irrigated conditions . Suitable for kharif and summer seasons. Highly resistant to foliar diseases and tolerant to major pests. Green fodder yield is 60 t/ha. Raj chari-1 : Developed from the cross between CSV6 x NCL3 and released in 1981. Resistant to stem borer and is non-lodging. Green fodder yield is 45 t/ha. Raj chari-2: A selection from local type of Udaipur region. Resistant to stem borer with high digestibility. Green fodder yield is 33 t/ha. UP chari-1: A single plant selection from Durra caudatum ( Maje Vari-Junagarh ) IS-4776, released in 1983. It is not suitable for high rainfall areas. Very low in HCN and can be fed to animals at any growth stage. UP chari-2: Developed from the cross between Vidisha-60-1 x IS 6953 by pedigree selection, released in 1984. It is not suitable for high rainfall areas. Suitable for late sown conditions too. Green fodder yield is 38 t/ha. Pusa chari-1 : Selection form sample collected from Uttar Pradesh released in 1974. It is resistant to lodging, drought and pests. Highly responsive to fertilizers. Green fodder yield is 33 t/ha.

31. 31 Multicut varieties/ hybrids: PCH 106: It has profuse tillering and quick regeneration capacity and provides 3-4 cuts. Yields up to 65 t/ha of green fodder . Meethi Sudan: It provides 55-60 t/ha of fodder in 4 cuts. It is tolerant to drought and waterlogging. The stems are sweet and thin with profuse tillering .   Dual purpose varieties/ hybrids: CSV 15 : It is a single cut variety with 45 t/ha of green fodder yield. Its stems are tall, sweet and juicy. It is resistant to leaf diseases and drought. CSH 13: A hybrid suitable for taking single cut of fodder. It is resistant to leaf diseases and yields about 45-50 t/ha of green fodder. Seeds and Sowing The seed rate varies from 25 (small seeded) to 40 kg/ha (bold seeded varieties) in single cut varieties. For multicut varieties the seed rate of 10 kg/ha is optimum. The crop is sown in in rows of 30 cm (single cut) to 45 cm ( multicut ) apart with a plant to plant spacing of 15 cm. The seed is sown at a depth of 2-5 cm. Mid to end of June is the optimum time of sowing for single cut varieties and April – mid May for multicut varieties under assured irrigation. In tarai region of Uttar Pradesh, last week of May to first week of June is the best . In rainfed , it should be sown after onset of monsoon.

32. 32 Manures and Fertilizers FYM application @ 10 ( rainfed ) to 25 t/ha (irrigated) before sowing is needed for higher fodder production. All single cut varieties respond up to 120 kg N/ha. However, crop is fertilized with 80-40-0 (single cut), 120-60-0 (double cut) and 210-60-60 ( multicut ) kg/ha of N-P 2 O 5 -K 2 O, respectively. 50% of total N (single cut, 40 kg; double cut, 60 kg; and multicut , 60 kg/ha) N along with entire P 2 O 5 and K 2 O are applied as basal. The remaining 50% N is top dressed 35-40 days after sowing (single cut) and 30 days after first cut (double cut varieties). In multicut varieties, 50 kg N is top dressed after each cut. At top dressing, adequate moisture should be ensured either through irrigation or it should be applied after rainfall. Irrigation Sorghum as a rainfed kharif crop needs no irrigation. However, at times of drought irrigation 35 days after sowing is advantageous. In summer, the crop requires 5-6 irrigations at 10-15 days interval depending on soil & climate.

33. 33 Weeding Weeds at early stages of crop growth compete for water and nutrients, and finally leading to heavy yield losses. Summer ploughing followed by 1-2 hand- weedings or intercultivations between 15-35 days after sowing may considerably reduce weeds and associated losses. However, interculturing becomes difficult during rainy season. Therefore, use of herbicides is recommended. Atrazine @ 1 kg/ha (pre-emergence) and 2,4-D @ 0.75-1.0 kg/ha (post-emergence 25-35 days after sowing) can effectively control weeds in fodder sorghum. For control of witch weed [ Striga gesnerioides ( willd .) Vatke ], use of dicamba (foliar spray) or metolachlor (pre-emergence) herbicides along with trap cropping have been advocated. Cropping Systems: For higher and quality fodder production, intercropping of sorghum with legumes is advised. Its intercropping with cowpea (normal rainfall areas) and guar( low rainfall areas) in 2:1 ratio is promising. For intercropping, erect genotypes of legume are ideal.

34. 34 Diseases Sorghum crop suffers from a number of diseases. The important diseases and their control measures are described below. Downy mildew ( Sclerospora sorghi ): Infested seedings have pale yellow narrow leaves that are covered on both sides by soft white downy growth of fungus. The affected plants remain stunted and dry up permanently. It is severe in Tamil Nadu, Karnataka, Maharashtra, Uttar Pradesh and Madhya Pradesh. The control measures include treatment of seed with agrosan GN or ceresan @ 4 g/kg seed and spray of dithane Z 78 (0.2%) to reduce secondary infection. The diseased plants should be removed and buried into the soil. Anthracnose ( Cercospora sorghi ): The disease appears as small spots on leaves and lower parts of the plant, which spread upwards later on. The leaf spots are light brown at center and dark at the margins. Seed treatment with agrosan GN @ 3 g/kg seed followed by spray of zineb (0.2%) at 10 days interval starting from 35 days after sowing can control the disease .

35. 35 Insect Pests Sorghum shoot fly ( Atherigonis varies soccata ) The maggots bore into the stem and feed on main shoot, and finally destroy the growing point. Result in tillering , and in severe infestation the tillers are also attacked them also. The seedling stage is more prone to attack though the attack continues up to early boot stage. Application of carbaryl 10 G or phorate 10 G or endosulfan 3 G @ 5 kg/ha and foliar spray of endosulfan @ 0.07% is effective in borer management. Early sowing (1st week of June) may avoid shoot fly attack. Stem borer ( Chilo partellus ) The caterpillars bore into the stem, and also the leaf prior to entering the stem. The young larvae feed on the leaves before boring downwards through the central whorl and reach the growing point. The characteristic symptoms are production of “Dead Hearts”. Foliar spray of carbaryl (0.05%) 2-3 times at 10-15 days interval is effective in borer management. Release of Trichogramme egg parasites may also reduce the stem borer incidence. Cyst nematode ( Heterodora sorghi ) This is most commonly observed in Delhi and Haryana regions. A deep summer ploughing reduces nematode population. Carbofuran seed treatment @ 2-3% and soil treatment with sebuphos @ 2 kg/ha and tobacco dust application @ 2.5 q/ha are effective in nematode management.

36. 36 Harvesting Single cut varieties are harvested at 50-100% flowering stage. In multicut varieties, the first cut is taken 55 days after sowing and the subsequent at 40 days interval. In multicut varieties, first cut should be taken 8-10 cm above ground level so as to facilitate profuse tillering . The crop at early stages contains hydrocyanic acid (HCN) or Dhurrin . HCN in excess of 200 ppm concentration is toxic to animals. Hence harvesting should not be done prior to 45 days from sowing. Heavy nitrogen fertilization and water stress (drought) increases HCN content. Silage or hay making removes the toxin. In summer, an irrigation before harvest may be effective in reducing HCN. For hay making, pre-flowering is ideal stage for harvest. At this stage, the biomass is soft and rich in nutrients. Yield The green fodder production varies from 30-45, 45-65 and 65-105 t/ha in single, double and multicut varieties, respectively. The protein content of single/ dual purpose cultivars is ~7% and has an invitro dry matter digestibility (IVDMD) of ~50%.