The maize aphid Rhopalosiphum maidis. Colony on leaf of maize (c) www.inra.fr
These are common on sorghum. The sorghum aphid is light yellow in colour, and the maize aphid is dark green to bluish-green in colour.
These aphids are often found sucking on ear heads or on the underside of leaves. They produce large quantities of honeydew, which enable black sooty moulds to grow.
Attacked plants sometimes are stunted, leaves dry up and yield is reduced. Young plants suffering from drought stress may be killed. Aphids can be a problem during dry periods.
Heavy aphid infestations on sorghum at the booting and heading stages seriously reduce both grain quality and yield.
The maize aphid transmits the maize dwarf mosaic virus to sorghum.Adults are small, 1-4 mm long, soft-bodied insects.
What to do:
Conserve natural enemies. Parasitic wasps and predatory insects, including lady bird beetles, damsel bugs, lacewings, and hover fly larvae are important in natural control of aphids.
Green stink bug (nymphs and adults). Adults are about 1.2cm long. (Host: Pearl Millet) (c) Russ Ottens, University of Georgia, Bugwood.org
A number of bugs feed on the milkripe sorghum grains: shield bugs including stink bugs (Nezara viridula, Acrosternum spp), Mirperus jaculus, Riptortus dentipes, Lygus bugs, blue bug (Calidea degrii) among others. The bugs puncture the seeds and suck the contents. Feeding punctures remain as dark spots on the testa.
The seed weight is reduced; the rate of germination may be depressed. Sorghum is most susceptible to bug damage during the milk and soft dough stage. Injury normally is not damaging from hard dough to maturity.
The damage is only of economic importance when bugs are present in large numbers.
What to do:
Use neem-based pesticides. Reportedly they reduce feeding by green shield bugs.
Check for bugs by beating or shaking panicles over a sweep net or bucket.
Kufura kwa kichwa na macho kufura ni ugonjwa gani na dawa gani?
What causes poultry to swell head and eyes and which disease and treatment to give?
From: Mr. Mutuku,County: Makueni, Kenya.
Discussion:
The chicken are having some raised swellings like pimples and some wounds. Their eyes do not seem to open fully and look swollen. They have not been given any vaccination. There are wart like lesions on the head and especially on the comb and wounds around the eyes and this is suggestive of Fowl pox which is a viral disease that affect chicken.
Dear Mr. Mutuku,
The chicken having swollen eyes, pimples and wounds or ulcers around the eyes could be suffering fromFowl pox disease caused by a pox virus. Introduction of infected birds in the flock would cause an outbreak by direct contact, through feed or water. Flying insects like mosquitoes can also transmit the virus from bird to bird and nearby flocks.
Fowl pox can be in 2 forms; i.- external or cutaneous, mainly on the head and lesions are wounds on the face as you have observed, combs cloaca, skin of legs, and the lesions are wart-like, yellow or dark brown in colour. ii. – internal or wet pox with lesions in the mouth, gullet and trachea. The lesions are cheesy and yellow-white in appearance and the bird have labored breathing, lack of appetite and are depressed.
For laying birds, there will be reduction in egg production. Treatment of infected chicken is difficult but local lesions can be treated with a disinfectant. Supplementation of infected chicken with multivitamins like Amilyte or Cosvita boost the chickens’ immunity against the disease and stress. Preventive vaccination is the most successful control method. In an outbreak of Fowl pox that has been diagnosed, it is advisable to vaccinate the chicken immediately so as to stop further spread of the infection. Fowl pox vaccine is given @ 3 weeks and 6 weeks of age, and is given as a wing jab.
Fowl pox is a viral infection of chicken seen as lesions in the skin in its cutaneous form, and lesions in the upper gastrointestinal and respiratory tracts in its wet or diphtheritic form. The skin lesions are on various parts of un-feathered skin of the chicken.
In the wet form the lesions develop on the mucous membrane of the mouth oesophagus, larynx pharynx and trachea. Preventive vaccination is by far the most successful control method. Because the infection spreads slowly, vaccination is always helpful in limiting the spread in affected flock, and therefore in an outbreak where fowl pox that has been diagnosed, it is advisable to vaccinate the flock immediately to stop further spread of the infection.
Shoot fly (Atherigona soccata) The adults are dark brown, and similar to a housefly, but nearly half the size. (c) Courtesy EcoPort (http://www.ecoport.org): Georg Goergen
Right, deadheart, egg on leaf, inset: (the adult shoot fly is about 0.5 cm). Females lay single cigar-shaped eggs on the undersides of leaves at the 1- to 7-leaf stage. The eggs hatch after only a day or two of incubation, and the larvae cut the growing point of the leaf, resulting in wilting and drying. These leaves, known as ‘deadheart’, are easily plucked. When a deadheart is plucked, it releases an obnoxious odor. (c) icrisat.org
It is the most important pest of sorghum at the seedling stage. The adult is similar to the housefly, smaller in size (3-5 mm long), and greyish in colour, and abdomen yellow with brown patches.
The larvae or maggots are yellowish or whitish in colour, up to 8 mm long. The fly lays eggs either at the base of young shoots near soil surfaces, or in older plants, on the leaves.
The maggots crawl inside the sheath and bore into the heart of the young shoot killing the growing point and the youngest leaf, which turns brown and withers. This damage is known as “dead heart”.
When good growing conditions prevail the young plants are usually able to compensate the damage by producing new tillers, which may partly escape attack, but later the ripening of the ear heads will be unequal. In weak plant repeated infestation may cause serious losses.
Sometimes the damage is so severe that many seedlings die and the field has to be replanted. Older plants (over 30 days after seedling emergence) are generally not damaged by the shoot fly.
However, when shoot flies are abundant (during the rainy season under moderate temperatures and high humidity) older plants may be attacked, but they do not produce the dead-heart symptoms. Instead, the damaged leaf becomes thin and papery, and wraps around the other leaves.
As a result, the plants may fail to grow normally.
Late infestations may also damage the panicle in the formative stage, resulting in rotting or drying up of a portion of the panicle affected by shoot fly damage.
What to do:
Conserve natural enemies. A range of natural enemies attacks the sorghum shoot fly: parasitic wasps attack eggs and maggots and predators cause high mortality of eggs. In particular, several species of spiders are important predators on eggs.
Field sanitation. Crop residues should be collected and destroyed after harvest to reduce carry-over from one season to another.
Plant resistant or tolerant varieties where available: Trials in Southern Africa has shown significant differences in resistance to shoot fly damage among varieties tested. Although the level of resistance in many of the sorghum varieties was low, several varieties with moderate levels of resistance were identified. Varieties “Pirira-1” and “Pirira-2” were the most resistant across seasons (van den Berg et al, 2005). In Eastern Africa, varieties “Serena” and “Seredo” showed high levels of recovery following shoot-fly damage (CABI; ICRISAT).
Early sowing make often possible to have the period of vulnerability (seedling stage) over by the time the flies emerge.
Uniform sowing of the same variety over large areas with the onset of rains reduces the damage by sorghum shoot fly.
High seeding rates helps to maintain optimum plant stands and reduce shoot fly damage. There are reports that shoot-fly damage is higher when plant densities are low (CABI, 2000).
Balanced fertiliser application. Application of fertiliser has been related to lower damage by shoot-fly possibly by increasing plant vigour. However, shoot-fly damage has been found to be greater in plots treated with cattle manure. This may have been due to the attraction of shoot flies to the odours emanating from the organic manure.
Intercropping. It has been shown that shoot fly damage is reduced when sorghum is intercropped with leguminous crops.
Fallowing and a closed season reduce the carryover and build-up of the shoot fly from one season to the next. These practices have been successfully used to reduce shoot-fly damage at ICRISAT. However, they may not practical for small-scale growers due to the shortage of land.
Nymphs and adults of the head bug (Calocoris angustatus) and the African head bug (Eurystylus oldi) feed on developing kernels as panicles emerge from the boot.
Head bugs are small (3 to 5 mm long, and about 1 mm wide) and variable in colour from yellowish green (C. angustatus), or pale brownish-yellow to dark brown with red markings (E. oldi).
Females insert long, cigar-shaped eggs between the glumes or anthers of sorghum florets. Eggs usually hatch in less than a week. Nymphs and adults suck juice from developing kernels as panicles emerge from the boot. Kernels attacked early in development are shrivelled, small, and off-coloured, resulting in yield loss.
Bug-damaged kernels become infected by secondary pathogens that further deteriorate grain quality. Feeding punctures are visible on older kernels. The life cycle is completed in about three weeks.
At least two generations feed on the same crop when panicles in the field do not mature at the same time.
What to do:
Conserve natural enemies. Assassin bugs and lygaeid bugs prey on ear head bugs.
Selection of varieties. Open panicles are less affected than compact panicles.
Resistant varieties. Some sorghum varieties are resistant to bugs.
Timing of planting. Damage is less severe when kernels develop during dry periods.
Red-Billed Quelae Bird This bird is one of them most dangerous of all agricultural pests in Africa, and causes food shortages in many countries. (c) Courtesy EcoPort (http://www.ecoport.org) : C.Elliott.
A flock of Red-billed Quelea birds (c) Alastair Rae, wikipedia
Red-Billed Quelae Bird Nest The nest is made in the form of a pouch with a roof and an entrance near the top. The male is responsible for the construction which is completed by a remarkable technique of weaving strips of grass back and forth to form a mesh-like structure. This is why the quelea bird is called a ‘weaver bird’. If the nest is accepted by a female, she will enter and in due course produce a clutch of three eggs. (c) Courtesy EcoPort (http://www.ecoport.org) : C.Elliott
Birds are one of the most important pests of sorghum. They are capable of causing heavy losses.
In Africa the most notorious species is Quelea quelea and is found in the Sahel region, from Senegal in West Africa through to Sudan, Uganda, Kenya, Southern Tanzania, Malawi, Zambia and South Africa.
What to do:
Damaging birds are mainly controlled by scaring them away from the sorghum fields and attacking their nesting sites. But not all birds are harmful. Some are also important predators and prey on insect pests of crops.
What can I do to my cow and calf to grow faster? I use booster. Is it advisable?
Dehorning in calf.
From: Bernard,County: Vihiga, Kenya.
Discussion:
Bernard is very interested in improving his dairy cows and calves and would take up the right information and put it in practise. Dairy cow feeding and calf management are of particular interest to him.
Dear Bernard,
For healthy and productive dairy cow the feed ration should have energy, proteins, fibre, vitamins, minerals supplements and water all in the right quantity and quality. Energy is the most limiting nutrient in dairy production and it is on this basis of energy content you can buy a concentrate or feed additive like booster for supplementation. Feedstuffs for a dairy cow are forages like hay, nappier grass, silage, green grass, sweet potatoes vines, lucerne, minerals supplements, concentrates and free access to fresh clean drinking water at all times. Forages have high crude fibre and good quality forage is the base of high milk production and should be fed at the right stage of growth usually around their flowering.
Calf rearing is very important as the calf’s growth rate during the first 60 days of life determine the future potential of the animal. A calf requires good feeding regime and a clean environment. In week 1 to week 2 of age, the calf continues to depend on liquid diet, milk (or milk replacer from a reliable manufacturer) for its growth and should consume about 10% of its body weight and is about 4 litres of milk; 2 litres in the morning and 2 litres in the evening.
Week 2 to week 3, introduce high quality forage which has fine texture and mixed with legumes like sweet potatoes vines. Supplement the calf with starter pellets or calf starter at this time. Give the calf clean fresh drinking water, about 4 litres divided into 2 portions between milk feeding. This continues for up to 6 weeks. From Week 6, reduce the amount of milk, encourage taking of dry feeds and introduce mineral supplements by giving a mineral block as a background lick.
Water intake increases with age, allow free access. Week 9 to 12 weeks of age, wean the calf. At weaning there is withdraw of milk which should be done gradually, e.g. to one litre daily and eventually to nil. This is done so as to avoid stress and also allow a calf’s digestive system to adjust to new diet. By this time the calf is now dependent on other feeds. Pneumonia and dirrhoea are the main ailments in calves and can be prevented and controlled with proper hygiene and management.
Dehorning has the benefit of a herd free from damage like severe injuries and bruises caused by horns and decreased risk injury to farm workers. It is advisable to dehorn animals at a young age, at least before they attain the age of 2 months when the horn buds become attached to the frontal bone of the skull.
Dehorning at a young age has advantages of lowering stress on the calf and the procedures are easier with less risk. Young calves recover much quicker and have fewer complications than older calves and adult cattle. There are various choices of dehorning methods like hot-iron dehorning, chemical dehorning and surgical disbudding. The procedure in calves should be done by a qualified vet paraprofessional or a vet. Calves and cattle require observation and aftercare following the procedure.
Grain moth (Sitotroga cerealella). The moth is small, pale brown, 5-7 mm long with wings folded, wingspan 1-1.6 cm. (c) Clemson University – USDA Cooperative Extension Slide Series, Bugwood.org
Sorghum is very susceptible to damage by storage pests, the main ones being greater grain weevils, in particular the rice weevil (Sitophilus oryzae), the flour beetle (Tribolium castaneum) and the grain moth (Sitotroga cerealella).
Heavily attacked grain loses much of its content and become unfit for sale and consumption.
What to do:
Damage can be minimised by drying grain adequately before storage. Cultivars with hard grain also suffer less damage.
Cutworm (Agrotis sp.) Early instars are about 7-12 mm long. Fully grown caterpillars are 35-50 mm long. (c) A.M. Varela, icipe
Chafer grub (Schyzonycha spp.) (c) A. M. Varela.
Several species damage sorghum. They may cut off young plants at or slightly below the soil surface. Some feed on above-ground plant parts, and others feed on the roots.
Plants with severed stems die, leaf feeding by cutworms causes ragged leaves and feeding on roots may kill young plants or stunt older plants.
Chaffer grubs (Schizonycha spp.) also feed on roots and may kill very young seedlings.
Stand loss can occur within 10 days after plants emerge in severely infested fields.
What to do:
Harrow and plough field and remove weeds well ahead of planting the crop in the field. Ploughing exposes caterpillars to predators and to desiccation by the sun. If the field is planted soon after land preparation some cutworms may be alive and attack the new crop.
Inspect soil carefully when preparing land for planting for the presence of cutworms or white grubs.
Monitor damage by counting damaged and freshly cut young plants.
Collect and destroy cutworms. Cutworms are found in the soil close to damaged plants at day time. Monitor for cutworms at dawn.
Sorghum (Sorghum bicolor) head (c) Courtesy EcoPort (http://www.ecoport.org): Li Dajue
Sorghum grain heads are dried in the sun on the threshing floor until the seeds drop easily. Threshing is done with a patole – a hand held flattened instrument made from torchwood (c) Courtesy EcoPort (http://www.ecoport.org): J. van den Berg
Geographical distribution of Sorghum in Africa. Updated on 10 July 2019. Source FAOSTAT
General Information and Agronomic Aspects
In Africa, a major growing area of sorghum runs across West Africa south of the Sahara almost to the coast and eastward into Sudan, Ethiopia, and Somalia. It is grown in upper Egypt but is a minor crop along the north African coast.
It is commonly grown in Uganda, Kenya, Tanzania, Rwanda, and Burundi and fairly important in Zambia, Malawi, and drier areas of Mozambique. It is important in Botswana and Lesotho and common in South Africa, and minor in Namibia.
Sorghum is perhaps the world’s most versatile crop. Some types are boiled like rice, some cracked like oats for porridge, some “malted” like barley for beer, some baked like wheat into flatbreads, and some popped like popcorn for snacks.
A few types have sugary grains and are boiled in the green stage like sweet corn. The whole plant is often used as forage, hay, or silage. The stems of some types are used for building, fencing, weaving, broom making, and firewood.
The stems of other types yield sugar, syrup, and even liquid fuels for powering vehicles or cooking meals. The living plants are used for windbreaks, for cover crops, and for staking yams and other heavy climbers. The seeds are fed to poultry, cattle, and swine.
(Lost Crops of Africa, Vol I, 1996) Sorghum plays an important role as a food security crop especially in semi arid lands of Kenya. It can survive drought conditions for some weeks by rolling up its leaves and thus decreasing transpiration.
Please also check KARI update: “Sorghum helps provide better food security”, July 1997, available in English on http://www.kari.org/ENGLISH/Sorghumfood.htm (click to follow link)
Climate conditions, soil and water management
Sorghum is adapted to a wide range of environmental conditions and will produce significant yields under conditions that are unfavourable for most other cereals. Sorghum is particularly adapted to drought. Sorghum also tolerates water logging and can be grown in areas of high rainfall.
It is, however, primarily a plant of hot, semi-arid tropical environments with rainfall from 250 mm that are too dry for maize but performs best with more than 900 mm annually. It is also grown widely in temperate regions and at altitudes of up to 2500 m in the tropics.
Sorghum tolerates a wide range of temperatures. Sterility can occur when night temperatures fall below 12-15degC during the flowering period. Sorghum is killed by frost.
Sorghum can be grown successfully on a wide range of soil types. It is well suited to heavy clay soils (vertisols) found commonly in the tropics, where its tolerance to water logging is often required, but is equally suited to light sandy soils.
It tolerates a range of soil pH from 5.0-8.5 and is more tolerant to salinity than maize. It is adapted to poor soils and can produce grain on soils where many other crops would fail.
Propagation and planting
Sorghum is normally grown from seed. A fine seed-bed is preferable
but is often not achieved. The seed is usually sown directly into a
furrow after ploughing, but can also be broadcast and harrowed into the soil. Optimum plant spacing depends on soil type and availability of moisture.
For favourable conditions, row spacing of 45-60 cm and plant-to-plant spacing of 12-20 cm, giving populations of about 120 000 plants per ha, are normal. For drier or less fertile conditions, wider spacing and lower plant populations are usually optimal.
The seed rate varies from 3 kg/ha in very dry areas to 10-15 kg/ha under irrigation. Occasionally, seedlings are grown in a nursery and transplanted into the field early in the dry season, e.g. on the flood plains round Lake Chad in Africa.
Production zones in Kenya and recommended sorghum varieties and their major characteristics:
Eco-zone and area
Variety
Maturity months
Grain colour
Yield potential (90 kg bags/acre)
Special attributes
Moist-mid-altitude Busia, Siaya, Kakamega, Kisumu, Homabay, Kuria, Migori, Coffee zones of Meru, Embu and Nyeri Districts
“Serena” “Serodo” “KARI/Mtama1”
3.0 3.5 3-3.5
Brown Brown White
12 12 15
Wide adaptability Tolerant to striga Wide adaptability Tolerant to stem borers. Attractive to birds
Semi-arid low lands Machachos, Kitui, Makueni, Mwingi, Lower Embu and Tharaka Nithi, Kajiado, Parts of Rift Valley, Parts of North Eastern Provinces
“IS76” “KARI/Mtama1” “KARI/Mtama2” “Gadam”
“Serena” “Serodo”
3 3-3.5 3.5 3.5
3 3.5
White White White Greyish
Brown Brown
10 15 15 8-20
12 12
– Tolerant to stem borers. Attractive to birds Resistant to birds Tolerant to stem borers, shoot fly and foliar diseases Wide adaptability. Tolerant to striga Wide adaptability
Cold semi-arid Highlands Nakuru, Baringo, Laikipia, Naivasha, Narok, Parts of Koibatek, Taita Taveta
“E 1291” “E 6518” “BJ28”
7 8 7
Brown Brown Brown
12 15 12
Dual purpose. Good beverage quality Dual purpose. Good beverage quality Dual purpose
Wide adaptability Wide adaptability Tolerant to stem borers. Attractive to birds Tolerant to stem borers, shoot fly and foliar diseases
Examples of some sorghum varieties grown in Uganda
“Epuripur”:
This is a white seeded variety, resistant to shoot fly and stem borers
but susceptible to bird damage. It yields about 2.5 – 3.0 tons per ha.
Grains are sweet and can be used for food, baking and brewing.
“Sekedo”:
It is a dwarf variety (100 cm) with brown-red seeds. It is tolerant to
stem borers and moderately resistant to shoot fly. It is recommended for
food and feeds. It matures in 100 days with a yield potential of 4 – 5
tons per ha
“Seredo” (variety characteristics as in Kenya).
“Serena” (variety characteristics as in Kenya).
Examples of some sorghum varieties grown in Tanzania for regions Dodoma, Mwanza, Shinyaga, and Singida
“Seredo” (variety characteristics as in Kenya).
“Serena” (variety characteristics as in Kenya).
“Macia” (“SDS 3220”) white grain; early maturing (80 days); yield potential 4t/ha
“Pato” (“SDS 2293-6”) grain colour cream/yellow white mottled; early maturing (80 days); yield potential 4 t/ha.
“Tengemeo” (“2KX17/B/1”) grain colour creamy white; early maturing (80 days); very good drought resistant; attractive to birds; resistant to major diseases and insect pests; good brewing quality; good storage; yield potential 4 t/ha.
“Lugugu” (Landrace; white grain).
“Udo Msonga” (Landrace; brown grain).
“Msumbji” (“IS7173”) (Landrace; high aluminium tolerance).
“PN3” white grain; high grain yield (4 t/ha); good storage; very good brewing quality; insect and disease reaction poor; poor bird resistance.
Husbandry
Sorghum is usually grown as a rainfed crop, sown after the onset of the monsoon season. Seeding rates are often higher than optimum to compensate for poor seed-bed or to allow for unfavourable moisture conditions. All sorghum varieties require a fine seed bed for better seedling establishment.
If tractor or oxen are used to open up a shamba, it is advisable to harrow after the first ploughing. When jembes (hoes) are used for land preparation, farmers are advised to ensure that large clods are reduced by breaking them to provide a smooth seed bed.
The planting field should be prepared well in advance of sowing. Seed rate is 7-10 kg/ ha or 3-4 kg/acre. Dry planting is highly recommended. Thus plant before or at the onset of rains by either drilling in the furrows made by tractor or oxen plough, or hill plant in the holes made by jembe or panga. When dry planted, planting depth should be 5 cm but when planting in a moist soil use planting depth of 2.5-4 cm.
Common row spacing is 75 cm and distance between plants about 20 cm. In semi arid areas where the ox plough yoke is fixed at 90 cm especially in Machakos, Makueni, Kitui and Mwingi districts, the recommended spacing between plants is 15 cm.
Subsistence farmers rarely apply fertiliser, as responses depend on moisture availability, which is usually very uncertain. Under more favourable conditions, farmyard manure is used with advantage, but even so the quantities used are usually below optimum.
Optimally sorghum needs the availability of about 20 kg N/ha and 20 kg P/ha at planting time, which can be supplied by alternate cropping with legumes and application of compost or manure. Also intercropping with legumes is recommended with grain legumes such as beans, cowpeas, pigeon peas and green gram.
Manure and compost improve organic matter content of the soil, soil moisture retention ability and soil structure. Manure can be broad cast in the field or applied in planting furrows and mixed with soil before seeds are planted.
The standard farm wheelbarrow when full holds approximately 25 kg of dry manure/compost. At a low rate, two wheel barrows are enough for a 10 m by 10 m area.
This translates into 200 wheelbarrows or 5 tons/ha. When aiming for high rate apply 400 wheelbarrows or 10 tons per ha.
The crop is usually weeded by a combination of inter-row cultivation with animal-drawn implements and hand weeding within rows.
Thinning is carried out at the same time as hand weeding, or at intervals during the crop cycle, particularly where thinnings are used to feed livestock.
Gapping by transplanting thinnings is encouraged when thinning is done within 2 weeks after emergence and when the soil is moist.
Sorghum ratooning
Ratooning is a practice of getting more than one harvest from a single sowing. Two ratooning systems have been identified. One in the bimodal rainfall zones in semi arid lowlands giving 2 crops and the other in the moist mid altitude coffee zones where the local varieties are the two seasons ratooning type.
A ratoon crop compared to a newly sown crop has an established root system which will utilizs the available water in the root zone for crop growth early in the season, reduce ploughing and planting labour and avoid migratory quelea birds in August by maturing early.
In bimodal rainfall zones of semi-arid lowlands in Eastern province sorghum is planted in short rains (October- November).
When the crop is mature, it is harvested in February and immediately ratooned to take advantage of the long rain season which starts in mid-March.
To achieve good yields, the crop is thinned to 2-3 tillers per hill. Weeding and other management practices are done as for a newly sown crop.
Harvesting
Sorghum is usually harvested by hand when it has reached physiological maturity – which means the grain is hard and does not produce milk when crushed.
Cut the heads with sickles or a sharp knife from plants in the field or cut the whole plant and remove the heads later. Sun dry the harvested panicles to a moisture level of 12-13 % and thresh and store the grain.
