Tag:

Fungal Disease

Blackberry Anthracnose: A Common Fungal Disease and How to Control It

by Gregory July 6, 2022

written by Gregory 5 minutes read

Blackberry Anthracnose: A Common Fungal Disease

Blackberry anthracnose is a common fungal disease that affects blackberries and other brambles, such as dewberries, loganberries, and raspberries. It can cause poor fruit quality and production, and in severe infections, it can weaken or even kill canes.

Symptoms of Blackberry Anthracnose

The first signs of blackberry anthracnose are small purple spots on the shoots of new canes in the spring. These spots will increase in size, become oval-shaped, and eventually turn a gray or buff color. You may also find small spots with light gray centers and purple margins on the leaves. In heavy infections, the spots on the canes and stems can merge together, forming large cankers with cracks.

Causes of Blackberry Anthracnose

Blackberry anthracnose is caused by the fungus Elsinoe veneta. The fungus overwinters in diseased canes and releases spores during rainy periods in the spring and summer. The greatest risk of infection is between bud break and pre-harvest, as the fungus targets mainly new growth.

Treatment for Blackberry Anthracnose

The best way to control blackberry anthracnose is to use a combination of cultural practices and fungicides.

Cultural Practices:

Plant resistant varieties of blackberries.
Space plants properly and prune to improve air circulation.
Remove any wild brambles in the area, which can harbor the disease.
Remove weeds and prune back blackberry bushes to promote good air circulation and light penetration.
After harvesting blackberries, remove and destroy any canes that have been infected.

Fungicides:

Apply a delayed dormant spray before growth starts and while temperatures are still cold.
Use a lime, sulfur, copper hydroxide, or foliar fungicide.
The recommended type of fungicide may vary depending on your area, so check with your county extension office for the latest information.

Prevention of Blackberry Anthracnose

The best way to prevent blackberry anthracnose is to start with healthy plants and to follow good cultural practices.

Buy disease-free plants from a reputable nursery.
Plant blackberries in well-drained soil.
Water blackberries deeply and regularly, especially during hot, dry weather.
Fertilize blackberries according to the soil test recommendations.
Mulch around blackberry plants to help retain moisture and suppress weeds.
Avoid overhead watering, which can spread the fungus.
Inspect blackberry plants regularly for signs of disease.

Additional Information

Life Cycle of the Anthracnose Fungus:

The anthracnose fungus overwinters in diseased canes. In the spring, the fungus produces spores that are spread by wind and rain. The spores infect new canes through wounds or natural openings. The fungus then grows inside the cane, causing the characteristic symptoms of anthracnose.

How to Identify Blackberry Anthracnose:

Blackberry anthracnose can be identified by the following symptoms:

Small purple spots on new canes in the spring
Oval-shaped, gray or buff spots on canes and stems
Small spots with light gray centers and purple margins on leaves
Cankers with cracks on canes and stems

Home Remedies for Blackberry Anthracnose:

There are a few home remedies that may help to control blackberry anthracnose, but they are not as effective as fungicides.

Baking soda: Mix 1 tablespoon of baking soda in 1 gallon of water and spray on blackberry plants.
Apple cider vinegar: Mix 1 cup of apple cider vinegar in 1 gallon of water and spray on blackberry plants.
Garlic: Crush garlic cloves and mix them with water. Spray the mixture on blackberry plants.

Organic Treatment for Blackberry Anthracnose:

There are a few organic fungicides that can be used to control blackberry anthracnose.

Serenade: Serenade is a biofungicide that contains the bacterium Bacillus subtilis.
Actinovate: Actinovate is a biofungicide that contains the bacterium Streptomyces lydicus.
Mycostop: Mycostop is a biofungicide that contains the fungus Trichoderma harzianum.

When to Use a Delayed Dormant Spray:

A delayed dormant spray is applied before growth starts and while temperatures are still cold. This is the best time to apply a fungicide to control blackberry anthracnose because the fungus is most vulnerable at this stage.

Plant Health and Disease

Photinia Bush Diseases: Identification, Prevention, and Effective Treatment

by Gregory April 7, 2022

written by Gregory 3 minutes read

Photinia Bush Diseases: Identification, Prevention, and Treatment

Introduction

Photinia shrubs are popular for their attractive red-tipped new growth, but they can be susceptible to a common disease known as photinia leaf spot. This fungal disease can cause serious damage to photinia shrubs, leading to defoliation and even death if left untreated.

Identifying Photinia Leaf Spot

The main culprit behind photinia leaf spot is a fungus called Entomosporium mespili. This fungus thrives in cool, moist environments, and it attacks the vulnerable new growth of photinia shrubs. The first signs of photinia leaf spot are small, round, red spots on the surface of the leaves. As the disease progresses, these spots enlarge and turn into dark, purplish circles surrounding gray, dying tissue. The fungus can spread from new growth to older leaves, eventually covering the entire shrub with unsightly “sores.”

Life Cycle of Photinia Bush Diseases

The red-tipped photinia disease follows a definite pattern or cycle. The fungal spores spend the winter in fallen, infected leaves or in late-emerging new growth. These spores are released into the air in late winter or early spring, where they can land on nearby photinia shrubs. The spores spread through water splashing from one leaf to another, infecting the entire shrub.

Preventing Photinia Bush Diseases

Prevention is key when it comes to controlling photinia bush diseases. Here are some effective prevention measures:

Rake up fallen leaves: Remove fallen leaves, which can harbor fungal spores.
Remove infected leaves and branches: If your shrub is already infected, prune away all affected leaves and branches.
Cover the ground around shrubs: Apply a layer of mulch around the base of your photinia shrubs to prevent spores from reaching the leaves.
Avoid excessive pruning: Over-pruning can stimulate new growth, which is more susceptible to disease.
Plant resistant varieties: Consider planting photinia varieties that are less susceptible to leaf spot.

Treating Photinia Bush Diseases

If your photinia shrub does become infected with leaf spot, there are several treatment options available:

Chemical treatments: Fungicides containing chlorothalonil, propiconazole, or myclobutanil can be effective in treating photinia leaf spot.
Cultural practices: Improving air circulation and sunlight exposure around your photinia shrubs can help reduce the risk of disease.

Additional Tips for Managing Photinia Bush Diseases

Stagger new plantings: Avoid planting photinia shrubs too close together. This will increase airflow and reduce the spread of spores.
Maintain good garden hygiene: Keep your garden clean of fallen leaves and other debris to reduce the risk of disease.
Monitor your shrubs regularly: Inspect your photinia shrubs regularly for signs of disease, and take prompt action if necessary.

With proper care and maintenance, you can prevent and control photinia bush diseases and keep your shrubs healthy and vibrant.

Plant Diseases

Damping Off in Watermelon Seedlings: Prevention and Treatment

by Gregory February 16, 2021

written by Gregory 3 minutes read

Damping Off: A Threat to Watermelon Seedlings

Introduction

Damping off is a common problem that can affect many different types of plants, including watermelon seedlings. It is caused by a fungus called Pythium, which thrives in cold, moist environments. Damping off can cause the stems of seedlings to become weak and withered, eventually leading to the death of the plant.

Symptoms of Damping Off

The symptoms of damping off in watermelon seedlings are:

Wilting and falling over
Waterlogged and girdled stem near the soil line
Discolored and stunted roots

Causes of Damping Off

Damping off is caused by the Pythium fungus, which is found in the soil. The fungus thrives in cold, moist environments, which is why damping off is more common in the spring and fall.

Prevention of Damping Off

There are several things you can do to prevent damping off in watermelon seedlings:

Start seeds in pots: Starting seeds in pots allows you to control the temperature and moisture levels, which can help to prevent damping off.
Keep seedlings warm and dry: Pythium fungus thrives in cold, moist environments, so it is important to keep seedlings warm and dry.
Avoid overwatering: Overwatering can create a moist environment that is ideal for the growth of Pythium fungus.
Use a well-draining potting mix: A well-draining potting mix will help to prevent the soil from becoming waterlogged.
Space seedlings properly: Spacing seedlings properly allows for good air circulation, which can help to prevent the spread of damping off.

Treatment of Damping Off

If your watermelon seedlings show signs of damping off, you can try to treat them with a fungicide containing mefenoxam or azoxystrobin. Be sure to read the instructions carefully before applying the fungicide.

Additional Tips for Preventing Damping Off

Use clean pots and soil: Using clean pots and soil will help to reduce the risk of introducing Pythium fungus to your seedlings.
Sterilize your tools: Sterilizing your tools before using them on your seedlings will help to prevent the spread of damping off.
Avoid working in the garden when the soil is wet: Working in the garden when the soil is wet can create a moist environment that is ideal for the growth of Pythium fungus.
Remove infected plants immediately: If you see any seedlings that are showing signs of damping off, remove them from the garden immediately to prevent the spread of the disease.

Conclusion

Damping off is a common problem that can affect watermelon seedlings, but it can be prevented and treated with proper care. By following the tips in this article, you can help to ensure that your watermelon seedlings grow into healthy and productive plants.

Fruit Tree Growing

Cherry Brown Rot: Prevention and Treatment for Healthy Cherry Trees

by Gregory February 10, 2021

written by Gregory 3 minutes read

Cherry Brown Rot: A Damaging Disease for Cherry Trees

Cherry brown rot is a common and destructive fungal disease that affects cherry trees, as well as other stone fruits like peaches, plums, apricots, and almonds. Caused by the fungus Monilinia fructicola, brown rot can spread rapidly during warm, wet weather conditions, leading to significant crop losses.

How Does Cherry Brown Rot Spread?

The fungus that causes brown rot overwinters in fallen or mummified fruit, as well as in other infected plant material. In the spring, when temperatures rise and moisture is abundant, the fungus becomes active and produces spores that are carried by wind and rain to developing flowers and young fruit.

The longer the period of wet conditions, the shorter the incubation time for brown rot, and symptoms can develop rapidly. Spores are first produced on early-maturing cherries and then spread to late-maturing trees, affecting both edible and ornamental varieties.

Symptoms of Cherry Brown Rot

The initial symptoms of cherry brown rot are browning and death of blossoms. Infected blossoms may remain attached to the branch with a sticky residue, while those killed by frost typically fall to the ground.

On fruit, the disease manifests as small, firm, brown lesions that rapidly expand until the entire fruit is covered. Over time, the fruit dries and shrivels but remains attached to the tree.

Other symptoms of brown rot include:

Twig blight, which can weaken trees and make them more vulnerable to other infections and winter injury
Cankers, which are discolored and sticky lesions that can girdle branches and cause leaves to wilt and brown
Powdery gray spores on infected plant parts, especially in damp conditions

How to Prevent Cherry Brown Rot

The best way to prevent cherry brown rot is to use resistant cultivars. If you already have a cherry tree, there are several steps you can take to reduce the risk of infection:

Remove mummies and fallen fruit: Regularly remove any mummified or fallen fruit from around the tree to eliminate potential sources of infection.
Prune infected plant material: Prune off any branches or twigs that show signs of brown rot, including cankers and dead or dying tissue.
Create an open canopy: Prune the tree to create an open canopy that allows for good air circulation, which helps to dry out the leaves and reduce the risk of fungal infections.
Water from under the leaves: Avoid watering the tree from above, as this can splash spores onto the leaves and fruit, increasing the risk of infection.
Keep the area clean: Remove any debris, such as fallen leaves and weeds, from around the tree to reduce the number of potential hiding places for the fungus.

Treating Cherry Brown Rot

If sanitation and pruning measures have not been effective in controlling brown rot, fungicides may be used. Copper fungicides can provide some benefit, but they may not be sufficient in all cases.

Organic control methods include products containing pyrethrins and sulfur.

Always read and follow the manufacturer’s instructions carefully when using any fungicides.

Conclusion

Cherry brown rot is a serious disease that can significantly impact cherry production. By understanding the disease cycle, symptoms, and prevention and treatment methods, you can help protect your cherry trees and ensure a healthy harvest.

Roses

Rose Rust: A Common Fungal Disease and How to Treat It

by Gregory December 14, 2020

written by Gregory 4 minutes read

Rose Rust: A Common Fungal Disease

Rose rust is a common fungal disease that affects roses, caused by a fungus called Phragmidium. There are actually nine species of the rose rust fungus, which can be frustrating for rose gardeners because this disease can ruin the appearance of roses and even kill the plant if left untreated.

Symptoms of Rose Rust Disease

Rose rust typically appears in spring and fall, but can also occur in the summer months. It first appears as small, orange or rust-colored spots on the leaves, which will grow larger as the infection progresses. The spots on the canes of the rose bush may also be orange or rust-colored, but will turn black in the fall and winter. Severely infected rose leaves will eventually fall off the bush, and the plant may defoliate completely. Rose rust can also cause the leaves on a rose bush to wilt.

How to Treat Rose Rust

Like powdery mildew and black spot fungi, rose rust disease is caused by high humidity levels and temperatures. Keeping good airflow through and around the rose bushes will help prevent this disease from developing. Additionally, disposing of old rose leaves will help prevent the fungus from overwintering and re-infecting your roses the following year.

If your rose bushes do become infected with rose rust, you can treat them with a fungicide according to the manufacturer’s instructions. Be sure to also dispose of any infected leaves, as they can spread the fungus to other rose bushes.

Preventing Rose Rust

There are a few things you can do to help prevent rose rust from infecting your roses:

Choose resistant varieties: Some varieties of roses are more resistant to rose rust than others. When choosing new roses for your garden, look for varieties that are known to be resistant to this disease.
Provide good air circulation: Rose rust thrives in humid environments with poor air circulation. Make sure your rose bushes are planted in an area with good air flow, and avoid overcrowding them.
Water your roses correctly: Avoid overwatering your roses, as this can create a humid environment that is conducive to the growth of rose rust fungus. Water your roses at the base of the plant, and avoid getting the leaves wet.
Clean up fallen leaves: Dispose of any fallen rose leaves promptly, as they can harbor the rose rust fungus.
Prune infected canes: If you notice any canes that are infected with rose rust, prune them off and dispose of them immediately.

Rust on Roses Home Remedies

In addition to using a fungicide, there are a few home remedies that you can try to treat rose rust:

Baking soda: Mix 1 tablespoon of baking soda with 1 gallon of water and spray it on your rose bushes.
Neem oil: Neem oil is a natural fungicide that can help to control rose rust. Mix 1 teaspoon of neem oil with 1 gallon of water and spray it on your rose bushes.
Potassium bicarbonate: Potassium bicarbonate is another natural fungicide that can be used to treat rose rust. Mix 1 tablespoon of potassium bicarbonate with 1 gallon of water and spray it on your rose bushes.

How to Grow Roses Without Rust

Growing roses without rust is possible, but it requires some effort. By following the tips above, you can help to prevent rose rust from infecting your roses and keep your plants healthy and beautiful.

Newer Posts

Older Posts