Pest & Disease Early blight

Early blight

Alternaria solani

What is Early blight (Alternaria solani)?

Early blight (Alternaria solani) is a fungal disease that affects tomatoes and potato plants. It is distributed worldwide and occurs wherever these crops are grown. Symptoms include small black or brown leaf lesions, which enlarge and develop a yellow halo. Larger lesions have concentric rings, giving them a "bullseye" appearance. Infected fruit and tubers show sunken lesions with concentric rings. Warm and humid environmental conditions favor infection. Early blight can cause defoliation, reduced fruit size, and yield loss, making it economically significant for growers.

How does Early blight (Alternaria solani) occur?

Early blight reproduces primarily through asexual spores called conidia, produced by the fungus Alternaria solani. The conidia are dispersed through wind and splashing rain or irrigation. The fungus overwinters on infected crop debris and can survive in the soil for several years. Under favorable environmental conditions, such as warm temperatures and moisture, the conidia germinate and infect plant tissues through direct penetration or stomata. The disease cycle repeats with new infections, leading to the spread and progression of early blight in crops.

Symptoms

1 - Plant Health

• Alternaria solani, a fungal pathogen, negatively impacts plants. Infected crops yield smaller and lower-quality fruits, causing economic losses. • Collar rot weakens or kills seedlings, while potato tubers develop lesions, reducing quality. Defoliation decreases photosynthesis, leading to reduced yields.

2 - Soil Effects

Alternaria solani has significant impacts on soil. The fungus survives in soil through infected debris, increasing the risk of disease. Severe infections deplete soil organic matter and nutrients, negatively affecting fertility.

Solutions

1 - Cultural Practices

• Remove infected plant debris and practice field sanitation to minimize the presence of fungal spores. • Control weeds and volunteers, as they can serve as reservoirs for the disease. • Use disease-free seeds or transplants to prevent the introduction of the pathogen. • Rotate crops with non-susceptible hosts to disrupt the disease cycle and reduce the build-up of fungal populations. • Optimize tuber maturity and handle them carefully during harvest to minimize the risk of infection and lesion development. • Maintain good soil fertility levels, as healthy plants are more resistant to diseases, including Alternaria solani.

2 - Resistant cultivars

• Resistant cultivars for early blight. • Consult with local agricultural extension services or nurseries for more information on resistant cultivars suitable for your specific area.

3 - Biological control

• Biological control options for early blight include beneficial bacteria like Bacillus subtilis, fungi such as Trichoderma spp., and biofungicides like Serenade (Bacillus subtilis strain QST 713). • It is essential to follow product instructions and consult with local experts.

4 - Chemical Control

• Available fungicides for early blight include protectant fungicides like mancozeb and chlorothalonil, as well as quinone outside inhibitors (QoIs) such as azoxystrobin and pyraclostrobin. • Succinate dehydrogenase inhibitors (SDHIs) like fluxapyroxad and fluopyram are also effective against early blight.

FAQ

Do shade growing plants need any Sunlight?

Shade growing plants do need sunlight, although they require less than other plants. They need some direct sunlight each morning to help them photosynthesize and grow properly. Also, indirect sunlight throughout the day helps them stay healthy. Shade growing plants will benefit from the sunshine, but if they get too much or too little, then they can suffer the consequences. It's important to pay attention to the needs of your plants so that you can provide them with the proper light for optimal growth.

How often should you water indoor plants?

Indoor plants should be watered when the soil feels dry to a depth of about two inches, usually about once a week. A helpful technique to determine your plants' watering needs is to feel the soil before and after watering to get a sense of how long it takes to dry out. An important note to remember is that some plants require less water than others, and it's best to research the specific needs of your individual plants. Likewise, if your home is very dry, you might need to water more often as the lack of moisture can stress the plants and lead to problems like brown leaves and wilted stems.

Can my monstera plant get root rot?

Yes, a plant can get root rot. Root rot is a fungal disease that can be caused by over-watering, poor soil drainage, or high humidity levels in the air. Signs of root rot include yellowing leaves, wilting and stunted growth, and damaged or browning root systems. Sometimes it is difficult to detect root rot until the plant is removed from the soil, as the problems are mainly below the soil surface. Treating root rot usually involves removing the affected parts of the plant and replanting the unaffected ones.

Can I put my Monstera outside in summer?

No, you should not put your Monstera outside in summer. Monstera plants need warm, humid air to thrive, and direct sunlight can scorch their leaves. Instead, put your Monstera in a bright, sunny spot with indirect light, making sure the sun never directly hits the leaves. During the summer, keep your Monstera's soil damp and mist it occasionally to keep the leaves hydrated. At nighttime, keep the temperature around 16 - 21°C (60 - 70°F). You can definitely take your Monstera outdoors for short periods of time, just make sure to bring it back in if it starts to get too hot.

What happens if my monstera plant gets too cold?

If your monstera plant gets too cold, it will become vulnerable to pests, disease, or other damage. Cold temperatures can damage the leaves of the plant, causing them to become spotted or limp. The roots of monstera plants may also suffer in cold temperatures, leading to root rot or other diseases. Belonging to the tropical family, monsteras are used to warm environments and do not do well in cold temperatures, so it is important to ensure your plant is kept in conditions that suit their needs.

Is it possible to grow a vegetable garden in a small space?

Yes, it is possible to grow a vegetable garden in a small space. Gardening in a small space can be as simple as growing a few containerized plants in pots and raised beds, or as elaborate as vertically stacking planters, hanging pouches, and hanging baskets on a wall, railing, or fence. Regardless of the size of the space you are working with, some simple techniques such as companion planting, organic fertilizers, and water conservation can help you get the most out of your small vegetable garden.

Is peppermint herb green good for digestion?

Peppermint herb is indeed beneficial for digestion. The flavonoids in the herb support digestion by reducing inflammation in the digestive track, aiding in digestion and relieving indigestion, heartburn, and even the symptoms of irritable bowel syndrome. Additionally, peppermint is naturally rich in menthol, which helps to relax the muscles of the stomach, aiding in the digestion of food. Peppermint herb can be consumed in a variety of forms, such as teas, tinctures and capsules, as well as by adding the herb to food or directly to water or tea.

Should peppermint herb green be consumed daily?

No, peppermint herb green should not be consumed daily. This is because it contains high levels of menthol, which can be toxic if taken in large doses. Additionally, consuming large amounts of peppermint herb green could interfere with the absorption of essential minerals and vitamins, potentially causing vitamin deficiencies. For these reasons, it is best to consult with a doctor before incorporating peppermint herb green into your daily diet.