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What is Blight?

Let us first define blight to understand the blight meaning. Blight meaning depicts something similar to a symptom that can affect the crops grown for food and other plants by causing a lot of problems. When the crops are spoilt are damaged, it can be referred to as crop blight. The blight meaning is deeper than just spoiling the crop, which when increased the blight disease can kill the plants as well. The blight plant disease when caused by bacteria is called bacterial blight. Let us further understand the blight plant disease. 

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Blight Plant Disease 

The blight is caused by several microorganisms and the naming is done in accordance with their causative agents. 

Blight Disease

Causative Agent

Plants and Crops Affected


Fire Blight

Bacterium Erwinia amylovora

Pome Fruits, raspberry, pear, apple

Late Blight 

Water mould Phytophthora infestans 

Potatoes And Tomatoes

For future planting, the selection is done concerning the resistant varieties ensure it to be a different location and then destroy the plant. 

Bacterial Blight Of Rice

Bacterium Xanthomonas oryzae 

Rice crops 

Spraying the combination of Fytolanand adriamycin 100. Agrimycin 500 Bristoll and Terramycin 17 can also be used as a spray over rice crops.

Early Blight 

Species of the ubiquitous fungal genus Alternaria

Tomatoes and Potatoes

Remove affected parts of the plants. After the first fruit sets, remove the lower leaves. Ensure to plant the crops elsewhere the following year.

Leaf blight of the grasses 

Ascochyta species and Alternaria triticina

Wheat Crops

Use microbial and biological products, transplant treatment using streptomycin and sprays with plant activator and copper treatment is used. 

Chestnut blight

Fungus Cryphonectria parasitica

Matured American Chestnuts

Mud packs need to be applied to each affected canker in the chestnut trees.


  • Sudden and severe yellowing and rapidly browning, 

  • Spotting often seen as leaf spots

  • Withering

  • The dying of all the plants gradually includes the leaves, stems, flowers and already showing fruits or the entire plant at one go.

Bacterial Blight Disease spreads by a common aforementioned bacterium that persists in soil and water through wind-driven rains. The bacteria over the winter reside on the crop residues, seed, fall-sown cereals, and effects the perennial grasses. Spring infection is the consequence of any of these sources of blight disease by splashing of bacterial ooze by raindrops, from plant to plant which are in contact with the insects.

Bacterial blight first develops on the upper leaves during winter and relatively cooler periods, wet weather and even in the humid climate after the plants have reached the boot stage. Warm and dry weather stops the spread of disease and eliminates any further blight growth in the plant and the newly emerging leaves may be relatively free of bacterial infection.

Prevention of Blight and its Destructive Symptoms

  • Remove diseased leaves immediately as soon as they appear any delay might kill the plants.

  • Improve air circulation for free movement and for the leaves to breathe around plants.

  • Mulch around the plant base to reduce water splashing.

  • Do not use overhead watering instead use the sprinklers.

  • Control weeds regular pruning of unwanted plant growth must be done. 

  • Rotate crops every year and do not plant in the same location where blight was caused.


Even though humans are not the primary sufferers of the blight disease, we must take accountability in helping the farmers whose livelihood depends on the crops grown that are also helpful in feeding the entire nation. The blight that has caused millions of deaths can be unstoppable once it starts to spread, so educating the farmers about the agricultural necessities by an expert will prove to be very helpful.  

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FAQs on Blight

Q.1) Do the Leaves Get Affected by the Blight Plant Disease?

Answer: The leaf exhibits the primary symptoms of blight disease. The initial appearance of lesions on the leaf part of the plant is seen which rapidly engulf the surrounding tissue around and spreads the disease further. However, in advanced stages, the leaf spots may expand to entire areas of leaf tissue and thus kill by exhibiting blight symptoms.

Q.2) How to Treat Blight That Affects the Leaves?

Answer: The leaf starts to show lesions as a sign of blight in the initial stages many steps can be applied In your garden and made to use to prevent further from spreading blight. Often the moisture is collected by the leaf after watering it so it is advisable to water the plants in the early morning so the moisture will evaporate from the leaves. The closely packed foliage used should be thinned. After each session of pruning and cutting the tools must be bleached with a 1:10 bleach solution. Ensure to remove all debris from around your plants each spring before the leaves bud.

Q.3) How to Treat the Tree Blight?

Answer: When the tree is infested with the blight disease the cause being the Erwinia amylovora which is the main reason for fire blight. And in such cases, it is difficult to recover the tree from any kind of treatment. The only way to save the trees in this scenario is via pruning, all the branches off with shear and bleach to avoid spreading. Pruning the branches at least 12 inches below the wilted and discoloured branch that is last and throwing 100ft away from the tree is practically done to avoid spread.

Q.4) Is the Blight Plant Disease Contagious?

Answer.: An entire crop can be ruined due to late blight. Many fungus and bacteria are often touted to be carriers that spread this disease.  In the 1840s, the potato blight which now referred to as the light blight killed millions of people in Ireland. Fire blight is also contagious and causes damage to the entire forest area as well if the trees lie close by. The family members of Rosaceae like the loquat, crabapples, quinces, hawthorn, cotoneaster, Pyracantha, raspberry along apple trees and pears are highly affected by the contagious fire blight disease. And of such disease, the spread can be unpredicted as in extremities an entire orchard can be destroyed because of it. 

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