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Top Varieties: Best Blight Resistant Seed Potatoes
6 January 2025
Blight can wipe out your crop. Choosing the right blight resistant seed potatoes is crucial for a healthy harvest. Read on to find out the top varieties of blight resistant seed potatoes that will save your yield.
Blight, caused by the pathogen Phytophthora infestans, is a big threat to crops, black patches and rot in leaves and tubers, you need to detect early to manage.
Blight resistant seed potatoes like Sarpo Mira and Setanta are better as they need less chemical treatment, more yield and more sustainable farming.
Knowing the environmental conditions that favour potato blight, warm temperatures and high humidity, is key to growers to take preventive measures and reduce the risk of infection.
What is Potato Blight
Potato blight, also known as late blight, is a deadly disease that attacks potato crops. It’s caused by the pathogen Phytophthora infestans, if not controlled it will cause big damage. Conventional farming has delayed the breeding of genetically resistant potatoes, so crop yield and resilience are impacted. Growers need to know potato blight to protect their crop and get a healthy harvest.
Potato blight spreads fast under favourable conditions so it’s a continuous threat. Leaves develop dark brown patches, stems rot and tubers develop dark sunken areas, eventually a soft foul smelling rot under the skin. Early detection of these symptoms will help in management and prevention.
What is Potato Blight?
Potato blight is caused by the pathogen Phytophthora infestans. As the disease progresses it shows round dark brown patches on the leaves which quickly spread and shrivel and blacken the whole leaf. Stems blacken and rot and cause big damage.
Infected tubers develop dark sunken areas on the surface and soft foul smelling rot under the skin. This disease can wipe out a crop if not managed immediately.
How Blight Spreads
Potato blight spreads through spores that travel by wind and land on wet leaves. Heavy rain can wash these spores into the soil and they come into contact with tubers. The disease loves wet conditions so you need to monitor the weather and take good care of your plants to reduce the risk of infection.
Knowing how blight spreads will help you take preventive measures.
When Should I Look for potato blight in the UK?
In the UK potato blight thrives under certain conditions. It’s most common during periods that meet certain criteria so growers need to know these conditions to reduce the risk. The following sections will go into detail on these conditions.
Blight loves warm temperatures, high humidity, wet leaves, rapid weather changes and seasonal timing. Overwintered inoculum from the previous season can also trigger new infections. These conditions will help you anticipate and prevent blight.
1. Warm Temperatures
Blight develops when temperatures are between 10°C and 25°C, optimal is 15°C to 20°C. These conditions are common during the growing season in the UK so you need to monitor temperature fluctuations closely.
2. High Humidity
Long periods of high humidity above 90% are critical for blight. This is after heavy rain, foggy mornings or poorly ventilated crop canopy. High humidity creates an environment where blight can spread fast.
3. Wet Foliage
Potato blight needs wet leaves to infect the plants. Conditions that keep the foliage wet for 6 hours or more like overnight dew, rain or irrigation are ideal for the spread of the disease.
Keeping the foliage dry will reduce the risk of infection.
4. Rapid Weather Changes
Wet and warm weather alternating is a risk for blight. Rain followed by mild and humid conditions is particularly risky.
Rapid weather changes creates an environment where blight can spread fast and wide.
5. Seasonal Timing
Blight is most common from late spring to early summer (May-June) and mid to late summer (July-August). These periods coincide with rising temperatures and dense crop canopy which is perfect for blight to develop.
6. Overwintered Inoculum
Volunteer potato tubers or infected tubers left in the ground from the previous season can be a source of infection when conditions are right. Removing these potential sources of contamination will prevent new infections.
Blight
In the UK the Hutton Criteria is used to predict blight risk. It shows when the conditions are right for blight to develop so growers can take preventive measures.
Being informed with blight alerts will help you protect your crop better.
Why Choose Blight Resistant Seed Potatoes?
Blight resistant seed potatoes have many advantages over non resistant varieties. These potatoes are bred with multiple resistance genes so you don’t need to use chemicals. The following sections will go into the benefits and challenges of blight resistant and non resistant varieties.
Blight resistant varieties produce higher yields and are bred for good agronomic qualities, those with low blight resistance need frequent fungicide applications and still can lose significant crop due to rapid blight spread.
Benefits of Blight Resistance
Blight resistant potatoes like Setanta don’t need weekly fungicide applications as they are naturally resistant. This means less chemicals and a healthier environment and higher yields.
Cara is also good for various culinary uses so more appealing.
Non Resistant Varieties Challenges
Non resistant potato varieties require big investment in blight prevention, farmers make 15-20 fungicide applications per season. The late blight life cycle is just 5 days, it’s a continuous threat to these crops. So non resistant varieties have higher risk and cost.
Best Blight Resistant Seed Potato Varieties
Choosing the right blight resistant seed potato varieties is key to a successful and robust harvest. This section will show you some of the best varieties for blight resistance and agronomic qualities.
Sarpo Mira:
Sarpo Mira is famous for its unbeatable late blight resistance so a great choice for organic and low input farming. It produces a heavy crop of large uniform tubers and does well in dry conditions so good for areas with inconsistent rainfall.
Setanta:
Setanta has great resistance to both foliage and tuber late blight. High dry matter so good for roasting, baking and frying.
Setanta also produces a big yield of large uniform tubers so a profitable harvest.
Carolus:
Carolus has dual resistance to both foliage and tuber late blight so less chemical use. High dry matter so slightly floury when cooked so good for various uses.
Sally:
Sally has great late blight resistance so less chemical fungicides. High yield of uniform tubers and versatile for culinary uses, good for boiling, baking and mashing.
Orla:
Orla is a versatile potato with tuber blight resistance. Can be harvested early as a first early or left in the ground to mature as a maincrop so more flexibility in harvest periods.
Orla is popular among organic growers because of its blight resistance and low chemical inputs.
Growing Blight Resistant Potatoes
Proper soil preparation and consistent care during the growing season is key to get the best yield from blight resistant potatoes. Positioning potato plants in a well ventilated area can help reduce blight spread. Wider row spacing can delay the closing of the plant canopy and reduce humidity and blight risk.
More space between plants will improve airflow and reduce blight. These will maximize the benefits of blight resistant varieties and a healthy and productive crop.
More Tips to Prevent Potato Blight
Preventing potato blight is multi faceted. Proper storage will prevent blighted tubers from rotting and maintain crop integrity. Inspect stored potatoes regularly to prevent spread of rot.
Below are more tips, growing early varieties, crop rotation and good sanitation to reduce blight risks.
Growing Early Varieties
Growing early potato varieties reduces blight exposure by harvesting before peak infection period. Growing first early varieties allows farmers to harvest before blight outbreaks and avoid crop loss while growing potatoes.
Crop Rotation
Crop rotation breaks the disease cycle in the soil. A crop rotation schedule will prevent planting potatoes in the same area for at least 5 years so it will disrupt the disease cycle and reduce blight risk.
Good Sanitation
Good sanitation will prevent potato blight. Destroy infected plants as soon as symptoms appear to prevent the disease from spreading to healthy plants. This will maintain the overall health of the crop.
Conclusion
In summary choosing blight resistant seed potatoes offers many benefits, from less chemical use to higher yields. Knowing the conditions that favour blight, choosing the right varieties and taking preventive measures are key to growing potatoes. Do these and you’ll be on your way to a bountiful and healthy harvest.
FAQs
What is potato blight and how does it affect crops?
- Potato blight caused by the pathogen Phytophthora infestans shows as dark brown patches on the leaves, stem rot and tuber decay and can severely damage potato crops and lead to yield loss. Management is key to mitigate its impact on agriculture.
Why blight resistant seed potatoes?
- Blight resistant seed potatoes will reduce chemical treatments and give higher yields and robust disease protection. This will make your crop more resilient and support sustainable gardening.
How do I prevent potato blight in my garden?
- To prevent potato blight in your garden grow early varieties, crop rotation, more space between plants and good sanitation. This will reduce the risk of infection.
Which blight resistant potatoes?
- Sarpo Mira, Setanta, Carolus, Sally and Orla are top blight resistant potatoes which are known for their high resistance and good agronomic traits.
When does potato blight occur in the UK?
- Potato blight occurs in the UK in late spring to early summer (May-June) and mid to late summer (July-August) when the conditions are favourable.
