Citrus Tree Diseases

Citrus trees, like lemon, orange and grapefruit are included in the most popularly planted landscaping trees. With their adorable shape, glossy leaves, richly fragrant blooms and edible fruits, these plants are worth growing in your yard. Nevertheless, planting citrus trees is considered challenging by most hobbyists. In addition to the stringent care level and extended time required for fruit bearing, the incidences of citrus tree diseases and pests are high, especially when it is grown in cold climatic conditions.

Diseases of Citrus Trees

The general citrus tree care involves providing optimal sunlight, maintaining warm temperature, watering when the top soil dries, occasional fertilization and pruning once in a while. Nothing can be more disappointing than seeing your fully grown citrus fruit tree affected by diseases. So, before you come across such a situation, be thorough with the most common citrus tree diseases and pests reported in your area. That way, you can take preventive measures to reduce the chances of disease attacks, and at the same time, increase fruit yield. Listed below are common diseases afflicting citrus trees.

Citrus Canker
Of all the diseases of citrus trees, citrus canker is the most serious one that causes devastating damages. It is caused by bacteria, and results in formation of scabs (similar to halo lesions) in the leaves, branches and fruits. When detected in the early stages, this contagious disease is treated by applying antibiotic formulation. But, if the disease sets in, the affected citrus fruit tree is killed to reduce further spreading.

Citrus Sooty Mold
This is a fungal disease, characterized by black coloration of the affected citrus tree leaves. The black color is nothing but the spores of sooty mold. It is triggered by whitely, aphid and alike pest attacks, which leave a sticky, honeydew like substance on the dorsal side of foliage. Hence, treatment for this disease involves controlling insects with correct insecticide sprays, couple with copper fungicide application.

Citrus Greasy Spot
One of the destructive citrus tree diseases caused by fungus is greasy spot. After infection takes place, the fungal spores germinate within the leaf tissues, causing the lower leaf portion to develop slightly raised blisters. They appear greasy with time, hence the name citrus greasy spot disease is coined. Other symptoms of this citrus fruit tree disease are leaf yellowing and leaf dropping. Spraying copper fungicide two times in summer help in controlling this fungal disease.

Yellow Vein Chlorosis
Yellow vein chlorosis is named with reference to the yellowish coloration of the main vein and lateral veins. This may be caused due to several factors, of which some are phytophthora foot rot, overwatering, extreme low temperature, physical damage and other stressful growth conditions. While this citrus tree disease is concentrated on the leaves, the barks of diseased twigs may also be affected.

Citrus Melanose
If you notice scabs forming in citrus fruits, particularly in young stages, then it may be melanose disease. Amongst the citrus fruits list, it mostly affects older grapefruit trees. The fruit quality and the yield remain unaffected, but affected fruits have a lesser market value due to unsightly appearance. Along with fungicide application, pruning citrus trees is also an easy way to reduce this fungal disease.

Citrus Root Rot Disease
As the name goes, this type of citrus tree disease affects the root system. Hence, steps for containing the disease should be followed as soon as possible, before severe damage is exhibited to the upper parts too. Notable signs include developing brown patches in bark, oozing of plant sap, leaf turning yellow, premature leaf fall and browning of citrus fruits. Trim down all the affected twigs and spray appropriate fungicide in correct dose.

Scaly Bark Disease
Scaly bark disease, is caused by viral infection, and exclusively affects the bark portion. Also known as psorosis, it causes scale formation in the bark of sweet orange and tangerine. Under severe infection, the yield is reduced considerably. Two other commonly reported citrus tree bark diseases are citrus phytophthora gummosis (caused by fungi) and exocortis (caused by virus).

Besides the above mentioned citrus tree diseases, mild to severe pest infestation is also not unusual for this fruit bearing plant. Some citrus tree pests are aphids, citrus bud mite, orangedog caterpillars, whitefly, thrips, brown soft scale, snail and citrus red mite amongst others. Instead of adopting ways for treating citrus tree problems, it is always better to prevent them at the first instant. Once affected, the diseases and pests may spread to remaining trees, leading to significant decrease in the fruit yield.