Mango Diseases – Common Diseases Affecting Mango Production

Mango farming is impacted by many mango diseases. Here is a list of the common diseases:

Flowers diseases.

Powdery mildew

Powdery mildew is a fungal disease that commonly affects mango trees. It is caused by the fungus Oidium mangiferae.

Symptoms of powdery mildew in mango trees typically appear as a whitish-grayish powdery coating on the leaves stems flowers, and fruit of the tree. The affected areas may develop a dry and dusty texture, hence the name “powdery” mildew.

Figure 1. Powdery mildew white dusty spores on mango flowers.

The symptoms can be noticed on the inflorescence, and stalk of inflorescence. 

Cultural management practices for controlling powdery mildew flower diseases include:

1. Plant selection: Choose resistant mango varieties when planting new trees. Some varieties show less susceptibility to powdery mildew.

2. Proper planting: Select well-drained soil and provide adequate spacing between avocado trees to allow air circulation and reduce humidity.

3. Pruning: Regularly prune and thin mango trees to ensure proper air circulation and sunlight penetration. Remove any infected or diseased plant parts promptly.

4. Irrigation: Avoid overhead irrigation, especially during the evening or night. Water at the base of the trees to keep the foliage dry, as humidity promotes powdery mildew growth.

5. Fertilization: Maintain proper nutrient levels in the soil through regular fertilization. However, avoid excessive nitrogen fertilization, as it can increase susceptibility to powdery mildew.

Chemical management options for controlling powdery mildew flower diseases in avocados include:

1. Fungicides: Apply fungicides specifically labeled for powdery mildew control in avocados. Follow all instructions and guidelines on the product label regarding dosage, timing, and application method. Rotate or alternate between different modes of action to prevent the development of resistance.

2. Systemic treatments: Systemic fungicides, such as those containing active ingredients like triazoles or strobilurins, can be absorbed by the plants and provide protection from powdery mildew for an extended period.

3. Preventive treatments: Apply fungicides before the appearance of powdery mildew symptoms as part of a preventive control strategy. This can be particularly important during periods of high disease pressure or when environmental conditions favor its development.

It is essential to note that the specific management practices and chemical treatments may vary depending on the specific powdery mildew species affecting avocado flowers, local regulations, and individual circumstances.

Anthracnose.

Anthracnose is a fungal disease caused by the pathogen Colletotrichum gloeosporioides that affects mango flowers. In addition, it is one of the most common and destructive diseases of mango trees worldwide.

Description:

Figure 2. Blossom Blight of Mango. 

Anthracnose primarily affects mango flowers, but can also spread to other parts of the tree such as fruits, leaves, and twigs. The disease is characterized by the formation of dark brown to black lesions on flowers, which later spread and cause flower blight. Infected flowers may drop prematurely, resulting in reduced fruit set and yield.

1. Dark spots on flower petals:

Infected mango flowers may develop dark, sunken spots, usually surrounded by a yellowish halo. These spots can vary in size and shape.

2. Premature flower drop: Anthracnose-infected flowers may exhibit premature wilting and drop from the tree before they can fully develop.

3. Flower blight:

The fungus can cause the entire flower to become blighted, turning brown or black in color. This can lead to the death of the flower.

4. Discoloration of floral structures: Anthracnose can cause discoloration and browning of other floral structures, such as the calyx or sepals.

5. Reduced fruit set: If anthracnose affects a large number of flowers, it can significantly impact fruit set, resulting in a lower number of mango fruits developing on the tree.

Cultural Management:

1. Sanitation: Regular removal and disposal of infected plant debris from the orchard are essential to reduce the source of infection. Infected flowers and fallen plant parts should be collected and destroyed.

2. Pruning: Proper pruning practices, such as removing dead or diseased branches, can help improve air circulation and reduce humidity, which can inhibit the growth and spread of the pathogen.

3. Adequate spacing: Planting mango trees with an appropriate spacing between them helps to provide better air circulation, reducing the chances of infection.

4. Fertilization and irrigation: Proper nutrition and irrigation management can improve the overall health and vigor of mango trees, making them more resistant to diseases like anthracnose.

Chemical Management:

Chemical management of anthracnose in mango flowers typically involves the use of fungicides. Before applying any fungicides, it is important to identify the specific fungal pathogen causing the disease through laboratory testing. This will help determine the most effective fungicide and application method.

Fungicide sprays are usually applied during pre-flowering and flowering stages to protect the flowers from infection. Popular fungicides used for anthracnose management in mango flowers include Mancozeb, Chlorothalonil, and Thiophanate-methyl. However, it is important to read and follow the manufacturer’s instructions, as well as any local regulations and restrictions, before using any chemical treatments.

It is also important to note that the regular and excessive use of fungicides can lead to the development of fungicide resistance in the pathogen population. Therefore, it is advisable to rotate between different classes of fungicides and apply them in a strategic manner to maintain their effectiveness.

Mango malformation 

Mango malformation is a physiological disorder that causes abnormal growth and deformation of mango flowers, resulting in reduced fruit production. It is, therefore, caused by various factors, including nutritional deficiencies, hormonal imbalances, fungal infections, or genetic abnormalities.

Description:

Mango malformation is characterized by the distortion and misalignment of inflorescences, resulting in the formation of “witches’ broom-like structures. The affected flowers may have shortened petals, stunted or elongated flower parts, and poor pollen viability. Moreover, severe cases of malformation can lead to complete flower sterility, resulting in no fruit production.

Figure 3. Malformation in mango inflorescence

Cultural Management:

1. Pruning: Regular pruning is essential to remove and destroy malformed inflorescences and any infected plant material. This helps reduce the source of infection and promotes the growth of healthy flowers.

2. Nutrition management: Adequate and balanced nutrition is crucial for normal flower development. Regular soil testing can help identify and correct any nutrient deficiencies or imbalances. Supplementing with appropriate fertilizers can help improve flower health and reduce the risk of malformation.

3. Irrigation management: Proper irrigation practices are important to maintain optimal soil moisture levels. Excessive or inadequate irrigation can lead to stress, which can contribute to malformation. Irrigation should be done based on the specific needs of the mango trees.

Chemical Management:

Chemical management for mango malformation is not well established, as the disorder has multiple causes and is often influenced by physiological factors. However, some fungicides or growth regulators have been used experimentally to manage malformation.

1. Foliar fungicides: Fungicides such as Mancozeb or Copper-based fungicides can be applied as a preventive measure during the flowering stage. They help control any fungal infections that might contribute to malformation.

2. Growth regulators: Certain growth regulators, like Benzyladenine (BAP), have been tested for their ability to reduce malformation in mango flowers. These regulators can be sprayed during flowering to promote normal flower development.

It is important to note that chemical management should be used cautiously and in accordance with local regulations and recommendations. Integrated Pest Management (IPM) practices, which combine cultural, biological, and chemical control methods, are often more effective in managing mango malformation.

Leaf diseases.

Anthracnose

Anthracnose is a fungal disease caused by the pathogen Colletotrichum gloeosporioides that commonly affects mango trees, including the leaves. It can cause significant damage to mango foliage and overall tree health.

Description:

Figure 4. Mango leaves affected by anthracnose

Anthracnose on mango leaves appears as dark, irregularly shaped lesions that start small and grow larger over time. These lesions may have a yellow halo around them. As the disease progresses, the affected leaves may wilt, die, and eventually fall off. Severe anthracnose infection can lead to defoliation, weakening the tree and reducing fruit production.

Cultural Management:

1. Sanitation: Regularly remove fallen leaves and infected plant material from around the tree. This helps reduce the spread of the disease and the source of fungal spores.

2. Pruning: Remove and destroy any infected branches or leaves to prevent the spread of the disease. Prune the canopy to improve air circulation and reduce humidity, which creates an unfavorable environment for fungal growth.

3. Adequate spacing: Proper spacing between mango trees allows for better airflow and reduces the chances of disease transmission.

4. Nutritional management: Ensure that the soil has adequate nutrients, particularly potassium and manganese, which can help enhance the tree’s resistance to anthracnose. Regular soil testing can help determine any nutrient deficiencies and guide appropriate fertilization.

Chemical Management:

Chemical management of anthracnose on mango leaves typically involves the use of fungicides. It is important to identify the specific fungal pathogen causing the disease through laboratory testing to determine the most effective fungicide and application method.

Fungicides should be applied as a preventive measure during periods of high disease pressure. Recommended fungicides for anthracnose control on mango leaves include copper-based fungicides (e.g., copper hydroxide, copper oxychloride) and triazole fungicides (e.g., tebuconazole). Follow the instructions on the product label and comply with local regulations and restrictions when using fungicides.

Regularly alternating between different classes of fungicides can help minimize the risk of developing fungicide resistance. It is advisable to consult with local agricultural extension services or experts in mango cultivation to select the appropriate fungicide and develop an integrated pest management (IPM) strategy tailored to your specific situation.

Scabs.

Description.

Scab is a common fungal disease that affects mango trees and their leaves. The disease is caused by the fungus Elsinoe mangiferae and is characterized by the appearance of raised, scaly or crusty lesions on the surface of the mango leaves. These lesions can range in color from dark brown to black and often have a rough texture.

Figure 5. Leaves showing small spots with haloes and distortion of the margin

Common symptoms are brown spots with haloes, edge lesions, corky lesions on the lower surfaces of leaves, and elongated dark lesions along the main veins under the leaves. In wet weather, numerous small brown lesions or shot holes may form on young leaves leading to their defoliation. Other symptoms seen on leaves include lesions with centre scabs and numerous small lesions about 0.1 mm in diameter along secondary veins. Leaves often appear distorted due to the effects of marginal or edge lesions.

Cultural Practices

Cultural management practices can help in the prevention and control of scab disease in mango trees. Here are some recommended cultural practices:

1. Pruning: Regular pruning promotes good air circulation and sunlight penetration within the canopy, which helps in reducing the humidity levels that favor fungal growth.

2. Sanitation: Proper removal and disposal of fallen leaves and infected plant parts can help prevent the spread of the disease to healthy plants.

3. Irrigation: Avoiding overhead irrigation and using drip irrigation instead can help reduce the humidity levels and prevent the fungal spores from germinating.

4. Nutrient management: Providing balanced nutrition to the mango tree can help in maintaining its overall health and ability to resist diseases. Consult with a local agricultural expert to determine the appropriate nutrient requirements for mango trees in your region.

Chemical

Chemical management is sometimes necessary for effective control of scab disease. Fungicides containing active ingredients such as sulfur or copper-based compounds are commonly used to manage scab in mango trees. It is important to carefully follow the instructions provided on the fungicide label regarding dosage, application timing, and safety precautions.

When applying fungicides, it is advisable to rotate between different chemical groups to prevent the development of resistant fungal strains. It is also crucial to adhere to the recommended spray intervals to ensure effective control.

It is worth noting that chemical management should be used as a last resort, and an integrated pest management approach that incorporates cultural practices and biological control methods should be followed whenever possible. Additionally, consider consulting with a local agricultural extension service or pest management professional for customized recommendations based on your specific location and mango variety.

Bacterial cankers.

Bacterial cankers are another common disease affecting mango trees and their leaves. They are caused by bacterial pathogens, such as Xanthomonas campestris or Pseudomonas syringae. Bacterial cankers on mango leaves appear as dark, sunken lesions surrounded by a yellow halo. These lesions often ooze bacterial exudate, which may dry and form crusty patches.

What are the Symptoms?

1. Cankers on branches and stems: The disease primarily affects branches and stems, causing the formation of sunken, oozing lesions or cankers. These cankers often appear dark brown or black and may have a rough or cracked texture.

Figure 6. Bacterial Canker of Mango

2. Wilting and dieback: Infected branches may exhibit wilting and dieback, where the foliage turns brown, dries up, and eventually dies. This can lead to the progression of the canker from the branch towards the main trunk.

3. Gumming and oozing: Bacterial cankers in mango trees often result in the exudation of gummy substances or a yellowish-brown ooze from the cankered areas.

4. Bark discoloration: The infected bark surrounding the canker may show a dark brown to black discoloration, depending on the severity of the infection.

5. Reduced vigor and growth: Mango trees with bacterial cankers may exhibit overall reduced growth and vigor. The disease can weaken the affected branches and hinder the tree’s ability to produce healthy new growth.

Cultural management practices play a vital role in preventing and managing bacterial cankers in mango trees. 

Here are some recommended practices:

1. Sanitation: Promptly remove and destroy infected plant material, including leaves, branches, and fruits, to prevent the spread of bacterial pathogens.

2. Pruning: Proper pruning helps enhance air circulation and sunlight penetration, which can prevent prolonged moisture on the leaves, reducing the chances of infection.

3. Irrigation: Avoid overhead irrigation that can splash water onto the leaves, creating a favorable environment for bacterial growth. Opt for drip irrigation or other methods that minimize leaf wetness.

4. Nutrient management: Providing balanced nutrition supports tree health and helps it resist diseases like bacterial cankers. Consult with experts to determine appropriate nutrient management practices.

Chemical management of bacterial cankers in mango trees is challenging. Still, in some cases, it may be necessary to control severe infections. Copper-based bactericides such as copper hydroxide or copper oxychloride are commonly used for chemical control. However, it is essential to follow specific instructions on the labels of the chosen bactericide regarding application timing, dosage, and safety precautions.

Applying bactericides as a preventive measure before the rainy season or during periods of high bacterial activity can be effective. Regular monitoring of tree health and early detection of symptoms can help identify the appropriate timing for chemical management if required.

Remember, chemical management should be employed judiciously and as a supplementary approach alongside cultural management practices. Integrated pest management strategies that focus on preventive measures, such as cultural practices, should be the primary approach for managing bacterial cankers in mango trees. 

Alternaria leaf spot.

Description.

Alternaria leaf spot, also known as Alternaria, is a common fungal disease that affects mango trees. The disease manifests as small, circular spots on the leaves, typically dark brown to black in color. These spots can gradually increase in size and coalesce, leading to extensive damage to the foliage.

What are the Symptoms?

Leaf lesions are circular to irregularly shaped, tan to gray, 1 to 5 mm in diameter, and surrounded by a reddish brown border. In most cases, only lower leaves are infected, but a severe infection can defoliate the plant. On ripe fruit, sunken areas near the calyx are covered by a dark green, velvety growth. On stored fruit, a grayish-green mold may appear on the stem scar or calyx end and spread over the entire berry. Infected fruit becomes soft and shriveled.

Cultural management practices can help minimize the occurrence and spread of Alternaria leaf spot in mango trees. These practices include:

1. Sanitation: Regularly remove and destroy fallen leaves and debris from the vicinity of the mango tree to reduce the source of inoculum. This helps to break the disease cycle.

2. Pruning: Prune the tree to improve air circulation and light penetration within the canopy, as this creates an environment less favorable for fungal growth.

3. Water management: Avoid overhead irrigation or excessive watering as these can create a conducive environment for the disease. Instead, use drip irrigation to water the mango tree, ensuring the leaves remain dry.

4. Fertilization: Apply balanced and appropriate fertilizers to maintain the overall health and vigor of the mango tree. A healthy tree is better equipped to resist diseases such as Alternaria leaf spot.

Chemical management can be employed for severe infections or in cases where cultural practices alone are not sufficient. Fungicides can be used to control Alternaria leaf spot. It is important to follow the instructions provided on the fungicide label and apply it at the recommended rates and timings.

Some commonly used fungicides for Alternaria leaf spot management in mango trees include copper-based fungicides (such as copper oxychloride or Bordeaux mixture) and systemic fungicides (such as azoxystrobin or tebuconazole). Application should be done as a protective measure before the disease symptoms appear or during the initial stages of infection. Follow-up applications may be necessary based on the severity of the disease and weather conditions.

Grey blight.

Description

Grey blight, also known as anthracnose, is a fungal disease that affects mango leaves. It is caused by the pathogen Colletotrichum gloeosporioides. The disease typically starts as small, dark spots on the leaves, which gradually enlarge and become covered with a grey or black fungal growth. As the disease progresses, the leaves may become distorted, wilted, and eventually die.

Figure 7. mango leaf showing symtops of grey blight

1. Brown spots develop on the margin and at the tip of the leaf lamina.  They increase in size and become dark brown. Black dots appear on the spots which are acervuli of the fungus.

2. Survive on mango leaves for over a year. Spreads through wind-borne conidia.

3. Heavy infection is noticed during the monsoon when the temperature is 20-25oC.and high humidity.

Cultural Management

Cultural management practices for grey blight in mango leaves involve maintaining good tree health and promoting air circulation. Here are some key practices:

1. Pruning: Regularly prune the mango trees to remove dead or infected branches and promote better air circulation, which reduces the chances of fungal spore germination.

2. Proper irrigation: Avoid overwatering, as wet conditions can promote the growth and spread of the disease. Water the trees early in the morning to allow the foliage to dry quickly.

3. Sanitation: Remove fallen leaves and other plant debris from around the trees, as they can harbor fungal spores. This helps to reduce the inoculum source for future infections.

4. Fertilization: Maintain proper fertilization to ensure healthy tree growth. Healthy trees are less susceptible to grey blight infection.

Chemical

Chemical management practices for grey blight involve the use of fungicides to control the disease. Here are some common fungicides used for grey blight management:

1. Copper-based fungicides: Applying copper-based fungicides as a preventive measure can help control grey blight. These fungicides should be applied as directed on the product label.

2. Systemic fungicides: Some systemic fungicides, such as those containing azoxystrobin or tebuconazole, can be effective in controlling grey blight. These fungicides are absorbed into the plant tissues and provide long-lasting protection.

It is important to note that chemical management should be used judiciously and as a last resort after cultural practices have been implemented. Regular monitoring of the mango trees for early symptoms and prompt action can help minimize the severity of grey blight infections.

Fruits diseases.

Anthracnose 

Anthracnose is a fungal disease caused by Colletotrichum gloeosporioides that affects various parts of mango trees, including the fruit. It is one of the most significant diseases that can lead to economic losses in mango production.

When newly formed fruit are affected the anthracnose shows as large, sunken, black lesions and the fruits so affected drop off. Medium to large green immature fruit affected with pre-harvest anthracnose show large lesions that are glossy, black, and sunken. With this fruit, splits and oozing often occur.

Figure 8. Fruts showing sings of anthracnose 

Cultural management practices

1. Sanitation: Proper sanitation practices are crucial in managing anthracnose. Remove and destroy fallen leaves, twigs, and infected fruit from the orchard. This helps to reduce the inoculum levels and prevent disease spread.

2. Pruning: Thin out the mango canopy to improve air circulation and sunlight penetration. This aids in reducing humidity levels and creating an unfavorable environment for fungal growth.

3. Avoid over-fertilization: Excessive nitrogen fertilization can lead to more succulent growth, which is highly susceptible to anthracnose infection. Ensure balanced fertilization based on soil and leaf analysis to avoid excess nitrogen levels.

4. Irrigation management: Proper irrigation practices, such as applying water early in the day and avoiding overhead irrigation, help in reducing leaf wetness duration and minimizing disease development.

Chemical management:

1. Fungicides: Fungicides are an essential tool in managing anthracnose in mangoes. Several fungicides, including azoxystrobin, tebuconazole, and thiophanate-methyl, have been found effective against Colletotrichum gloeosporioides. Follow the manufacturer’s instructions and apply fungicides at recommended intervals to protect the fruit from infection.

2. Preharvest sprays: Prearrest sprays with recommended fungicides help in protecting the mature fruit from postharvest anthracnose development. These sprays should be applied a few weeks before harvest when the fruit is still green.

3. Postharvest treatments: Using fungicides after harvest is an effective way to control anthracnose during storage and transportation. Dip or spray the harvested fruit with recommended fungicides, such as imazalil or prochloraz, to minimize disease development.

It is important to note that chemical management should be integrated with cultural practices for better control of anthracnose in mango fruits. Regular monitoring of the orchard and prompt action in response to disease outbreaks are vital to minimize the impact of anthracnose on mango production.

Stem end rot.

Stem end rot, also known as blossom end rot or black tip, is a common fungal disease that affects mango fruit. It is caused by various fungal pathogens, including Lasiodiplodia theobromae and Colletotrichum gloeosporioides. Stem end rot typically occurs during the postharvest stage, but can also develop in the field under certain conditions

Symptoms:

Figure 9. Fruit infected with stem end rot disease

1. Initially, small, water-soaked lesions appear on the stem end of the fruit.

2. The lesions gradually enlarge and turn black or brown, becoming sunken and necrotic.

3. The rot can extend into the fruit pulp, causing disintegration and decay.

4. In severe cases, the entire fruit can become completely rotted and unfit for consumption.

Cultural management practices:

1. Proper harvesting: Harvest fruits at the optimum maturity stage to minimize susceptibility to stem end rot. Late-harvested fruits are more prone to this disease.

2. Avoid physical damage: Handle mango fruits with care during harvesting and postharvest handling to prevent any mechanical injury that can provide entry points for fungal infection.

3. Storage conditions: Maintain proper storage conditions, including temperature and humidity levels, to reduce the risk of fungal growth and the development of stem-end rot.

4. Enhanced ventilation: Provide adequate ventilation during storage to improve air circulation around the fruits and reduce humidity, which inhibits fungal growth.

Chemical management:

1. Pre harvest sprays: Apply fungicides, such as thiophanate-methyl or imazalil, during the pre-harvest stage to protect mango fruits from fungal infection. Follow the recommended dosage and application intervals provided by the manufacturer.

2. Postharvest treatments: Dip or spray the harvested fruits with fungicides like hot water treatments, fungicide solutions, or biological agents to prevent disease development during storage and transportation. Again, adhere to the recommended guidelines for the specific fungicide being used.

It is crucial to implement a combination of cultural and chemical management strategies to effectively manage stem end rot in mango fruits. Regular monitoring and prompt action are necessary to prevent the spread of the disease and minimize postharvest losses.

Decline/ malformation disorders.

Dieback

Dieback disorder in mango refers to a plant disease that affects the branches and shoots of the mango tree, leading to their death or decay. The disorder can result from various factors, including fungal or bacterial infections, environmental stress, nutrient deficiencies, or improper cultural practices.

Symptoms of dieback disorder in mangoes include the gradual wilting and drying up of branches and shoots. The affected parts turn brown or black, and their bark may crack or peel off. In severe cases, the affected branches may die completely.

Figure 9. Dieback disease in mango trees

Cultural management practices involve proper care and maintenance of the mango tree to minimize the occurrence of dieback. This includes providing adequate irrigation and drainage to prevent waterlogging, especially during the rainy season. Pruning diseased branches and removing any dead or decaying plant material can help reduce the spread of the disorder. Furthermore, ensuring proper spacing between trees and adequate sunlight can also promote airflow and reduce humidity, minimizing the favorable conditions for disease development

Chemical management helps in severe cases of dieback disorder. Fungicides or bactericides can be applied according to the specific pathogen causing the disease. It is essential to consult with agricultural experts or professionals to determine the most suitable chemical treatments, dosage, and timing based on the specific disease and its severity. It is important to follow the instructions and safety guidelines provided by the manufacturer when using chemical treatments.

Additionally, maintaining good orchard hygiene, practicing crop rotation, and using disease-resistant mango cultivars can help prevent or reduce the occurrence of dieback disorder in mango trees.

It is important to note that cultural and chemical management practices may vary depending on the specific location, climate, mango variety, and severity of the dieback disorder.

Twig blight.

Twig blight is a common disorder that affects mango trees. It is caused by various fungal pathogens, such as Colletotrichum gloeosporioides and Lasiodiplodia the obromae. This disorder can cause significant damage to the mango tree, resulting in reduced yield and an overall decline in tree health.

Symptoms of twig blight in mango trees include the presence of dark, sunken lesions on the twigs and branches. These lesions may initially appear as small, water-soaked spots but gradually enlarge and become darker. Infected twigs may also show dieback, with the leaves turning yellow or brown and eventually falling off. In severe cases, the entire tree can get the disease causing to tree mortality.

Figure 10. Symptoms of mango twig tip dieback on a mango flush

Cultural management practices can help prevent or minimize twig blight in mango trees. It is important to maintain proper tree hygiene by pruning and removing infected twigs and branches. This helps to reduce the spread of fungal spores to healthy parts of the tree. Additionally, maintaining optimal tree health through regular fertilization, watering, and maintaining proper air circulation can also help prevent twig blight.

Chemical management of twig blight in mango trees involves the use of fungicides. Fungicides containing active ingredients like azoxystrobin, thiophanate-methyl, and pyraclostrobin have been found effective against the pathogens causing twig blight. These fungicides should be applied as directed on the product label, usually during the dormant period or at the first signs of disease. It is important to follow proper safety precautions and recommended dosage rates when using fungicides.

Overall, a combination of cultural and chemical management practices can help control and prevent twig blight disorders in mango trees. Regular monitoring, timely pruning of infected parts, and proper fungicide applications can significantly reduce the impact of this disease on mango production.

Gummosis.

Gummosis disorder in mango trees shows the oozing or gummy sap on the bark and branches, similar to other fruit trees. Here is a description of the disorder, its symptoms, and the cultural and chemical management strategies for gummosis in mango trees:

Description:

Gummosis in mango trees is a fungal disease resulting from various pathogens. It usually infects the branches, trunk, and fruit of the tree, leading to the production of gummy sap. The disease can weaken the tree and affect its overall health and productivity.

Symptoms:

Figure 11. Gummosis in stem.

1. Oozing or gummy sap: The most obvious symptom of gummosis in mango trees is the presence of sticky, gummy sap on the bark, branches, and fruit. This sap can be clear or amber in color and may have a foul smell.

2. Canker formation: Gummosis can cause the formation of cankers on the infected tree, which are characterized by sunken, cracked, or discolored areas of the bark.

3. Leaf and fruit drop: The disease can lead to premature leaf and fruit drop, affecting the overall yield of the mango tree.

4. Bark discoloration: Infected areas of the bark may turn dark brown or black, indicating damage caused by gummosis.

Cultural Management:

1. Pruning: Regular pruning of infected branches and removing dead or diseased plant material can help control the spread of gummosis in mango trees.

2. Sanitation: Implementing good sanitation practices, such as removing and disposing of infected plant debris, can help prevent the disease from spreading to healthy trees.

3. Irrigation and drainage: Proper irrigation management, avoiding excessive moisture and ensuring good drainage, can help reduce the risk of gummosis infection.

4. Nutrient management: Applying balanced fertilizers and maintaining optimal nutrient levels can improve the mango tree’s resistance to fungal infections.

Chemical Management:

1. Preventive sprays: Fungicides containing active ingredients like copper or chlorothalonil can act as a preventive measure during the dormant season or before the onset of gummosis infection.

2. Systemic fungicides: In severe cases, systemic fungicides may control gummosis. These fungicides provide long-lasting protection against the pathogens. Consult with local agricultural extension services or experts to select appropriate systemic fungicides.

3. Follow label instructions: When using fungicides, carefully follow the instructions on the label, including recommended application rates, timing, and safety precautions.

It’s important to consult with local agricultural extension services or experts for specific recommendations and guidance on gummosis management in mango trees, as the effectiveness of cultural and chemical management may vary depending on the specific pathogen causing the disease and the local conditions.

Bark splitting.

Bark splitting disorder in mango trees is a physiological disorder that is from environmental factors. Here is a description of the disorder, its symptoms, and the cultural and chemical management strategies for bark splitting in mango trees:

Description:

Bark splitting in mango trees refers to the splitting or cracking of the bark, particularly on the trunk and branches. It can occur due to various reasons, including extreme temperatures, sudden changes in temperature, sunburn, excessive water uptake, or rapid growth. The splitting can weaken the tree and provide an entry point for pathogens.

Symptoms:

Figure 12. Mango tree bark splitting.

1. Bark cracking: The most noticeable symptom of bark splitting is the physical splitting or cracking of the bark. The splits can occur vertically or horizontally and may vary in severity.

2. Exposed inner tissue: The split bark exposes the inner tissue of the tree, which can be vulnerable to infection and damage.

3. Dead tissue: In severe cases, the split bark may lead to the death of the tissue underneath, resulting in the formation of cankers or sunken areas.

Cultural Management:

1. Pruning: Regular pruning can help maintain the tree’s shape and balance, reducing the risk of excessive growth and stress that can contribute to bark splitting.

2. Irrigation management: Proper irrigation practices, including deep and infrequent watering, can help prevent excessive water uptake, which can lead to bark splitting. Avoid wetting the trunk during irrigation.

3. Mulching: Applying a layer of organic mulch around the base of the tree can moderate soil temperatures and moisture levels, reducing stress on the tree and minimizing the risk of bark splitting.

4. Sun protection: Protect the trunk and branches from direct sunlight by using shading materials or paint specially designed to reflect sunlight and prevent sunburn.

Chemical Management:

There are no specific chemical treatments for bark splitting in mango trees since it is primarily a physiological disorder caused by environmental factors. However, applying a protective coating specifically formulated for tree bark, such as a tree paint or whitewash, to the exposed areas can help prevent sunburn and reduce moisture loss.

It is important to note that the best approach for managing bark splitting in mango trees is to focus on cultural practices that promote overall tree health and minimize stress. Healthy trees can handle environmental stressors and are less likely to develop bark splitting. Regular monitoring and prompt action in response to any symptoms or signs of stress can help mitigate the risk of bark splitting in mango trees.

Mango sudden death syndrome.

Mango sudden death syndrome, also known as mango sudden wilt, is a devastating disease that affects mango trees. Here is a description of the syndrome, its symptoms, and the cultural and chemical management strategies for mango sudden death syndrome:

Description:

Mango sudden death syndrome is a fungal disease caused by the pathogen Ceratocystis fimbriata. It primarily affects the vascular system of the mango tree, leading to wilting, decline, and eventually death of the tree. The disease is common in tropical and subtropical regions and can cause significant economic losses.

Symptoms:

1. Sudden wilting: The most striking symptom of mango sudden death syndrome is the rapid wilting of the entire tree or individual branches, often occurring within a few days or weeks.

2. Leaf discoloration: Infected leaves may exhibit a yellowing or browning discoloration, starting from the tips and progressing towards the base of the leaf.

3. Leaf drop: As the disease progresses, the affected tree sheds leaves prematurely, resulting in sparse foliage.

Figure 13.

4. Dark streaking: Dark streaks or lesions may appear on the branches, which can extend along the trunk, indicating the presence of the fungal pathogen.

Cultural Management:

1. Removal of infected trees: Infected trees should be promptly removed and destroyed to prevent the spread of mango sudden death syndrome to healthy trees.

2. Sanitation: Strict sanitation practices, including the removal and proper disposal of diseased plant material, can help minimize the risk of disease transmission.

3. Resistant rootstock: Planting mango trees on rootstocks that have shown resistance to mango sudden death syndrome can reduce the chances of infection.

4. Pruning and canopy management: Regular pruning to improve airflow and light penetration, along with reducing tree stress, can help mitigate the risk of infection and maintain tree health.

Chemical Management:

1. Fungicide application: Although there is no specific fungicide recommended for controlling mango sudden death syndrome, some studies suggest that systemic fungicides containing active ingredients such as propiconazole or thiabendazole can provide limited protection against the disease. It is important to consult with local agricultural extension services or experts for specific fungicide recommendations and application guidelines.

Given the challenges associated with managing mango sudden death syndrome, prevention through the use of disease-resistant varieties, cultural practices, and proper sanitation remains the most effective approach. Planting certified disease-free nursery stock and implementing proactive measures can help reduce the likelihood of infection and limit its impact on mango production. Regular monitoring and contacting local agricultural experts for guidance can aid in managing mango sudden death syndrome effectively.

References.

• https://kisan-app.agrevolution.in/hi/dehaat/post/Dieback-Disease-in-Mango-Trees.
• https://tribune.com.pk/story/2293590/contagious-crop-disease-plagues-sindhs-mango-fields.
• https://industry.nt.gov.au/publications/primary-industry-publications/newsletters/regional-newsletters/rural-review/nt-rural-review-november-2021/mango-common-dieback#:~:text=The%20main%20symptom%20of%20mango,are%20also%20a%20typical%20symptom.
• https://vikaspedia.in/agriculture/crop-production/integrated-pest-managment/ipm-for-fruit-crops/ipm-strategies-for-mango/mango-diseases-and-symptoms#:~:text=Anthracnose,-Disease%20symptoms&text=The%20disease%20causes%20serious%20losses,die%20back%E2%80%9F%20of%20young%20branches.
• https://www.canr.msu.edu/uploads/files/Alternaria%20leaf%20spot%20and%20fruit%20rot.pdf.
• https://leafplanttech.com/why-mango-trees-may-crack/#:~:text=Dry%20weather%20followed%20by%20wet,trunk%20will%20prevent%20sun%20scorch.