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Loose Kernel Smut

(Sporisorium sorghi)

Credits: Biovision-Infonet

**Loose kernel smut** *(Sphacelotheca cruenta)* on sorghum
(c) Courtesy EcoPort (http://www.ecoport.org): J. Kranz

It attacks all groups of sorghum including Sudan-grass and Johnson grass. Galls formed by loose kernel smut are long and pointed. The thin membrane covering the galls usually breaks soon after galls reach full size.

The dark-brown spores contained in the galls are wind-blown away leaving a long, dark pointed, curved structure (called columella), in the central part of the gall.

As in covered kernel smut, the spores of the fungus are carried on the seed and germinate soon after the seed is planted and invades the young sorghum plant.

It continues to grow unobserved inside the plant until heading, when the long pointed smut galls appear in the heads in place of normal kernels.

Unlike covered kernel smut, this disease stunts the infected plants and often induces abundant side branches.

What to do:

Certified disease-free seeds.
Plant resistant varieties.
Control weeds.
Rotation with non-cereals.
Practise good field sanitation.

Covered Kernel Smut

(Sporisorium sorghi)

Credits: Biovision-Infonet

The disease destroys all kernels in a head and replaces them with a cone-shaped gall or may affect only portions of a panicle. At harvest time, these galls are broken and spores contaminate the outer surface of other kernels.

What to do:

Use of certified disease-free seed.
Plant resistant hybrids.

Maize Dwarf Mosaic Virus (MDMV)

Credits: Biovision-Infonet

Maize dwarf mosaic is a virus disease that occurs over all the sorghum producing areas. Its ability to cause damage is dependent on the presence of an over-seasoning virus host (mainly Johnson grass), aphid populations to facilitate virus transmission and the susceptibility of the varieties being grown.

Affected plants have mottled (light green blotches) terminal leaves. These alternate light- and darker-green areas in the leaf can be more easily seen when held between the viewer and a light source.

Observers should always look at the newest leaves for the most severe symptoms. Highly susceptible hybrids are stunted with chlorotic symptoms in the upper leaves and suffer significant yield losses.

Some hybrids produce a red leaf symptom when plants are infected and when night temperatures are below 13degC .

What to do:

Use resistant or tolerant hybrids.
Control Johnson grass in and around the field.

Sorghum Anthracnose

(Colletotrichum graminicola)

Credits: Biovision-Infonet

The anthracnose fungus damages foliage and stems of grain sorghum. On susceptible hybrids, the stem holding the head (peduncle) becomes infected and a brown sunken area with distinct margins develops.

When infected stems are cut lengthwise with a knife, one can see that the fungus has penetrated the soft pith tissue and caused brick-red discolourations.

This peduncle infection inhibits the flow of water and nutrients to the grain causing poor grain development.

The fungus also invades individual grains and the small branches of the panicle. Rapid and severe yield loss can result from panicle and peduncle infections.

Leaf lesions are small, elliptical to circular, usually less than 0.9 cm in diameter.

These spots develop small, circular, straw-coloured centres with wide margins that may vary in colour from reddish to tan to blackish purple.

The spots may coalesce to form larger areas of infected tissue.

What to do:

Use resistant hybrids.
Rotate with non-cereals preferably with pulses.
Good management of crop residues.

Quick Search Sorghum Pests

Credits: Biovision-Infonet

Cutworms

**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.

Storage Pests

**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

Birds

**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.

**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

A flock of Red-billed Quelea birds
(c) Alastair Rae, wikipedia

Sorghum Shoot Fly

**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

African Armyworm

African Bollworm

Stemborers: Spotted Stemborer

**Spotted stemborer** *(Chilo partellus)*
(c) Courtesy EcoPort (http://www.ecoport.org): Agricultural Research Council of South Africa.

Other Bugs

**Green stink bug** *(nymphs and adults)*. Adults are about 1.2cm long. (Host: Pearl Millet)
(c) Russ Ottens, University of Georgia, Bugwood.org

The Sorghum Aphid and the Maize Aphid

The **maize aphid** *Rhopalosiphum maidis*. Colony on leaf of maize
(c) www.inra.fr

Sorghum Midge

Stemborers: African Maize Stalkborer

**African maize stalkborer** *(Busseola fusca)* damage on maize. Caterpillars are relatively featureless and noctuid, growing to a length of up to 4 cm. They lack conspicuous hairs or markings and look smooth and shiny. Colour is variable but usually creamy-white
(c) A. M. Varela, icipe

Infectious Coryza Disease

Dr.iCow’s Diary

Date: 13.02.2020

Dear Dr.iCow,

There is a poultry disease with whitish substances in the eyes. What is the cure of this disease?

From Charles,County: Makueni/ Kitui-Kenya.

Discussion:

The chicken have white substances in the eyes and their eyes are closing. This white appearance in the chicken eyes are inflammation of the eyes. On close observation there could be facial swelling and nasal discharge. This infection has similar signs with chronic respiratory disease.

Dear Charles,

The chicken with whitish substances in the eyes and the eyes are closing may be suffering from Infectious coryza which is presenting in a mild form with depression, nasal discharge and slight facial swelling.

Infectious coryza is a bacterial disease and is transmitted through contact, droppings and aerosol. It presents with watery eyes, inflammation of the eyes, facial oedema and anorexia, nasal discharge, swollen infraorbital sinus, laboured breathing and drop in egg production. There is reduced feed and water intake and drop in eggs production in laying birds.

It is a bacterial infection spread from bird to bird by contact, airborne infected dust particles and through drinking water. Early treatment is important and OTC-Plus and an antibiotic eye ointment can be given to subdue clinical infections.

Thank you

From your friend and advisor,

Dr.iCow

Fractures in Poultry

Dr.iCow’s diary

Date: 13.02.2020.

Dear Dr.iCow,

My hen has a broken leg. What should I do to help her recover?

From iCow Smart Farmer

Dear iCow Smart Farmer

The broken leg of the hen can be treated by giving the fractured leg bone the best conditions to heal itself. Bandaging or splinting, rest and physical therapy may help. The fracture should be properly and correctly aligned and the materials used should be firm enough to provide support. You may need to use bandages and splinting materials like wood applicator sticks or some small split wood pieces. Please isolate the bird from the flock, place her in a comfortable, safe, warm location with easy access to drinking water and nutritious feeds. Be gentle when handling chicken.

Fractures are very painful and may be caused by various accidents like strong forces and underlying diseases like osteoporosis due to a lot of egg laying which weaken bones. If attended early they heal in about 2 to 3 weeks.

Thank you

From your friend and advisor

Dr.iCow

Fowl Pox in Poultry

Dr.iCow’s Diary

Date: 13.02.2020.

Dear Dr.iCow,

Ugonjwa wa kupoteza macho kwa kuku na kuaga?

My poultry are losing sight and causing deaths.

From: Miriam,County: Makueni, Kenya.

Discussion:

The problem with the chicken is being unable to see because their eyes are closed. There are some wounds around the eyes and affected chicken are not feeding well. The problem is affecting the adult birds more than the chicks.

Fowl pox is a viral disease of chicken caused by a pox virus which is transmitted by introduction of infected or carrier birds in a susceptible flock. This will cause an outbreak by direct contact and transmission in water and feeds. Signs seen are skin lesions on the featherless skin, and internal lesions of mucous lining of the upper alimentary canal and respiratory tract, refereed to as wet pox. The cutaneous form and the wet pox may both occur with the cutaneous form being more frequent. The disease may come as an outbreak. Prevention is done through vaccination.Separate infected birds from healthy ones.

Treatment of infected chicken is difficult and local lesions can be treated using a disinfectant. Like all viral diseases there is no specific treatment of Fowl pox. Supplement all the chicken those infected and not infected with multivitamins like Amilyte w.s.p. or Cosvita Ws so as to boost the birds’ immunity against the disease and disease stress.

Preventive vaccination is by far the most successful control method and vaccination is done at 3 weeks and 6 weeks of age and is given by a wing jab.

It is ideal to prevent your poultry against Fowl pox and other diseases by vaccinating them.Please follow vaccine regime as advised via iCow SMS. This is the best and only sure way of protecting your chickens.

Successful rearing of healthy, growing and productive chicken from day old chicks to adult birds depend on; nutritious feeds, clean fresh drinking water, observance of strict sanitary and hygienic measures in chicken house, clean feeders and drinkers which should be free of algae and moulds, keep a clean environment, and vaccinating your chicken against epidemic diseases. The following is a basic vaccination program for some epidemic chicken diseases;

i. Gumboro vaccine – @ 10 days and 18 days of age, given in drinking water.

ii. Newcastle Disease -NCD vaccine (may be available combined with Infectious bronchitis -IB vaccine as NCD + IB) – is given @ 21days, 8 weeks, 18 weeks, and every 3 months thereafter. It is given in drinking water or through eye drops.

iii. Fowl pox vaccine given -@ 3 weeks and 6 weeks of age and is given by a wing jab. iv. Fowl typhoid vaccine is given – @ 8 weeks of age and given by intramuscular injection.

Please follow the recommended chicken vaccination schedule for control and prevention against these diseases. It is the most successful method.

Thank you

From your friend and advisor,

Dr.iCow

Termites

(Coptotermes formosanus)

Credits: Biovision-Infonet

Termites, also known as white ants are common pests of upland rice in West Africa where they may cause serious damage during dry periods. They may also occur in lowland areas in light texture soils.

They generally attack plants in their later growth stage by hollowing out their root system and filling it with soil resulting in the lodging of the rice plants. The attacked plants are then predisposed to further damage by ground-dwelling pests such as rodents, ants, and secondary infection by fungi and bacteria.

Damaged plants can easily be pulled up by hand because the roots are severed.

What to do:

Provide good growing conditions for the trees. Termites more often attack sickly or water stressed plants than healthy plants.
Plant early with the rain.

Sorghum Midge

(Stenodiplosis sorghicola)

Credits: Biovision-Infonet

It is reported as one of the most important pests of sorghum in some countries, whilst in others (e.g. Ghana) is considered a sporadic pest. Nearly 30% of sorghum grain was damaged by sorghum midge in 1990 in western Kenya.

In southern Africa, there are reports of 25% of sorghum grain damaged by sorghum midge (CABI, 2000). The adults are small (3 mm long), deep-red midges, with transparent wings.

Eggs are laid in the flowering heads. The small orange larvae feed in the developing seed. Attacked seeds become shrunken and flat resulting in empty or “chaffy heads” as shrivelled grains fail to develop.

The larva pupates inside the spikelet, and before adult emergence, the pupa wriggles its way to the tip of the spikelet. After adult emergence, the pupal case remains attached to the chaffy spikelet.

Thus, damaged panicles have small, transparent midge pupal cases attached to the tip of the damaged spikelets.

What to do:

Synchronised planting. Epidemics of sorghum midge damage are common within an area, when sorghum is not planted at the same time, or different cultivars are planted that do not mature at the same time. Although landrace varieties often flower uniformly, high-yielding, early-flowering cultivars often do not. Sorghum that is planted and flowers later than normal is exposed to sorghum midge for a longer period and can suffer severe damage.
Planting density and thinning. Midge damage is reported to be higher in crops with low plant density (CABI, 2000).
Selective removal of alternative hosts. Wild species of sorghum (for example, S. halepense and S. sudanense) act as alternative hosts for sorghum midge. Midge populations build up early in the season on wild species of sorghum and infest the sorghum crop later in the season. Removing these alternative hosts from the vicinity of the sorghum crop can reduce the rate of multiplication of sorghum midge populations. However, wild hosts also sustain the natural enemies, and thus may help in increasing the role of natural enemies in population suppression.
Field sanitation. Crop residues should be collected and destroyed to reduce the carryover of larvae in the chaffy spikelets from one season to another.
Fallowing and close season. Fallowing reduces the carryover and build-up of midge populations from one season to the next. However, this is not a feasible practice for smallholders due to the shortage of land.
Use tolerant or resistant varieties where available. High levels of host-plant resistance are available for sorghum midge. In India, varieties SPH 837 and Pratap Jowar 1430 are claimed to be tolerant to the midge damage (www.nrcjowar.res.in/aicsip2005/achievements_udaipur.pdf). Also in India, variety “DSV-3” is claimed to resistant to midge damage and is recommended to be planted in midge endemic areas (www.uasd.edu/research.htm).
Crop rotations. Sorghum is generally rotated with cotton, groundnuts, sunflowers or sugarcane. This may reduce the damage caused by the sorghum midge.
Mixed cropping. Damage by the sorghum midge is reduced when sorghum is intercropped with leguminous crops (CABI, 2000)