Cereal crops are essential crops grown worldwide. Whenever a grower grows cereals, several diseases affect them.
5 common diseases of cereal crops that affect them include powdery mildew, bacterial blight, seedling blight, leaf rust and barley dwarf virus.
These diseases are severe threats to cereal crops, causing damage and reduction in yield.
These diseases are caused by harmful pathogens such as viruses, fungi, and bacteria. Also, unfavorable cultivating conditions like unsuitable soil and climate can cause abnormal fruit, foliage, and root development.
Whatever the cause of cereal crop diseases, be it viral, bacterial, or fungal, it is very severe for plants and growers as this can reduce yield, which leads to economic losses.
This article will examine some common cereal crop diseases, their causes, and their controlling methods.
5 Common Diseases of Cereal Crops
These cereal crop disease attack cereals in different ways, causing plant illness and yield loss.
Powdery Mildew
Powdery mildew is one of the 5 common diseases of cereal crops. Mildew is a fungal disease caused by Blumeria graminis. White powdery spots appear on the leaves and stem of the plant infected by this disease. [1]
This fungal disease in cereal crops flourishes in humid conditions, and temperatures between 20 to 30 are ideal for this disease to grow.
White powder-like spots appear on the infected plant, the disease can infect any part of the plant above the ground, but the leaves are most affected.
Signs and Symptoms of Powdery Mildew
Powdery mildew can infect leaves, fruits, and flowers and the symptoms are:
- White power-like spots appear on the leaves; these spots enlarge and merge and cover the whole leaf
- Leaves can also develop reddish or purple blotches
- Infected leaf edges curl upwards, and fungal growth can be seen clearly
- On the underside of the leaves, tiny, black, round fungal structures can also be seen
- Infected fruit surfaces can crack and harden
- Fungus grows and spreads on the fruit and produces white mycelial, giving the fruit a powdery appearance
Preventions Against Powdery Mildew
- Make plants strong by practicing sound practices like proper watering and fertilization.
- Enhance airflow around the plants by maintaining proper spacing
- Remove any debris around the plants.
- If any plant shows the symptoms of powdery mildew, the plant should be removed immediately and disposed of so that the fungal spores should not be spread to other healthy plants.
- Regularly check the plant for the disease before it spreads.
- Growing powdery mildew-resistant varities such as Jimi 23- a wheat cultivar can help to prevent this disease.
- Chemicals such as Propiconazole and Trichoderma harzianum and compounds like horticulture and neem oil, insecticidal soap, and potassium bicarbonate are available to control this fungal disease.
- Check the label on the chemical for dosage, application, and other safety methods before spraying the chemical.
Bacterial Blight
Bacterial blight is another common and severe disease in cereals such as peas and beans. This disease is caused by a pathogen called Pseudomonas syringae pv. Glycinea.
Bacterial blight first shows appearance on leaves and stems as small, dark green, watery lesions. The lesions can merge and enlarge but always adhere to the veins and form a fan-like shape.
Leaf lesions turn yellow and then brown and thin, and pod lesions are sunken and olive brown. The disease stresses the plants, and even mature plants can die.
Symptoms of Bacterial Blight
- Water-soaked and light green spots on leaves
- Tissues turn brown and die
- Leave edges or interveinal areas can develop lesion spots
- The spots on the leaves become yellowish and then brown and thin.
- Pod spots olive brown, sunken
- Stem near the ground can build lesion spots
Preventions Against Bacterial Blight
- Practice integrated management such as disease-free seeds, crop rotation, etc.
- The sound drainage system in a crop field
- Remove weeds, hay, etc., to keep the crop field clean.
- The fallow field should allow drying; this help suppresses soil disease agents.
- Early sowing can make plants vulnerable to blight disease, so better to avoid early sowing and sowing at that time which is recommended for your area.
Also Read: Zucchini Plant Pest Control
Seedling Blight Disease
Seedling blight disease is caused by a pathogenic fungus- F. culmorum, F. graminearum, F. poae, and F. avenaceum. In cereal crops, this disease cause root, seed, or seedling and head blight to rot and die before germinating. [2]
Enormous damage is caused by seedling blight in germinating seedlings, which reduces plants in the field and leads to yield loss.
If seedlings germinate, their emergence may not occur, or seedlings may emerge; after that, they become brown and die.
Seedling Blight Disease Symptoms
- Seedlings fail to germinate
- Softening, browning, and shrinking of seedlings
- Seedlings become enlarged due to infection
- Infected cells collapse and dies
- Emerged seedlings’ roots and stems get infected near the soil or below.
Preventions Against Seedling Blight
- Select the quality seed for sowing
- Check seeds in a laboratory before sowing them
- Treat seeds before sowing can aid in seed protection and emerging seedlings
- Avoid deep sowing/planting; this helps minimize disease risk and quick emergence of seedlings
- Avoid weak or cracked seeds, as they can be an easy target for diseases
- Make proper drainage arrangement
Leaf Rust Disease
Among 5 common diseases of cereal crops leaf rust is one of them. Leaf rust, a fungal disease, is occurred by the fungus Puccinia Triticuna, and mainly leaves are affected by this disease.
Barley, wheat, and other cereal crops are effected throughout the world by this disease.
Surviving leaf rust disease requires a living host to stay from one season to another. This disease pores can travel long distances via wind and spread quickly to healthy plants under favorable weather conditions.
7 to 12 °C temperature and moisture on leaves are favorable for the infection, and a temperature between 10 to 16 °C is ideal for disease development. [3]
Symptoms of Leaf Rust Include:
- White or yellow spots are formed on the infected leaf’s upper surface
- Orange or reddish blisters known as pustules are formed on leaves’ undersides
- Pores are formed within the pustules
- Often, defoliation, and distortion of the leaf happens
Preventions Against Leaf Rust
- Plant-resistant varieties are the best and most natural way to control leaf rust. Growing resistant varieties can help prevent the disease in the long run.
- The disease can produce new strains that can attack resistant varieties, so growers must be aware of the disease-resistant types.
- For early infection, control of leaf rust seed treatment is available; this is necessary for susceptible varieties.
- Various fungicides are available for controlling the disease in wheat. But these fungicides should not be treated as resistant varieties substitute.
- Fungicides are used as a backup if a new strain of the disease arises and in regions where disease-resistant varieties are unavailable.
Barley Yellow Dwarf Virus (BYDV)
Barley yellow dwarf virus (BYDV) falls in the genus Lureoviruses of the family Tombusviridae. This genus contains 13 species of viruses.
Barley yellow dwarf virus causes diseases in cereal crops and affects many crops such as wheat, oats, barley, maize, and other grass species.
Aphids spread this cereal crop disease. Aphids get this disease when they feed on infected plants and transmit it to healthy plants. Over 20 species of aphids spread this cereal crop disease, such as green bugs, corn leaf aphids, etc.
The crops, sown early or the extended season crops grown in high-rainfall areas, are especially vulnerable to BYDV.
Symptoms of BYDV Include:
- Younger leaves get slightly discolored
- Barley turns golden-yellow,
- Wheat turns pale yellow
- Oats turned purple-red
- Slow plant growth and discoloration develop further
- Plants remain stunted in the late season
- Generally patched infection throughout the crop
- Delayed maturity
- Shriveled grain
How to Manage of BYDE?
- A preferred way to manage Barley yellow dwarf virus is disease-resistant varieties of crops. Many disease verities of wheat, barley, and oats are available to plant.
- Treatment of seed with imidacloprid (an insecticide) can be used if an aphid problem is likely to be happened during the first few weeks after sowing.
- Preventing aphid spread is necessary by using insecticides during the first eight to ten weeks after the crop emerges.
- Before using any insecticide or pesticide, consult an agricultural expert who can guide you to control the disease efficiently.
Conclusion
Cereal crops are essential crops around the world. Millions worldwide depend on these crops for living as they are the source of their income.
Diseases in crops can cause loss to the crops and the economy as the farmers spend millions on growing crops.
Above, we discuss 5 common diseases of cereal crops which pose a threat to these crops. These diseases attack cereal crops and cause crop and yield loss.
Information about these diseases, such as the cause, how they spread, and how to prevent them, is necessary for crop growers to protect themselves from losses due to these diseases.
