Often, potatoes grow have rough, brown skin with patches on them. This is a common yet serious disease that the potatoes and some other root crops suffer from known as the common scabs. This disease occurs generally during summer, and though light attacks are superficial, the stronger ones might ruin your crop.
However there are some easy steps, following which you can prevent the potatoes from being affected by bacteria like organism, Streptomyces Scabies which cause the common scab.
This is a cosmetic disease rather than a productive disease, but it is detrimental for selling the commercial crops. Therefore you need to keep in mind these preventive measures:
Taking Care of the Soil
Remember that the germs of the disease can be retained by the soil for a very long time. Therefore it is better not to plant other crops just before or after potato cultivation. However, if you have a smaller garden, this might not be a practical advice. Also keep in mind that commons scab worsens in alkaline soil, therefore, lime the soil properly.
Avoiding the Affected Seeds
choose the seeds carefully and do not plant the affected seeds or you are most certain to produce scab infected potatoes.
Watering the Soil
Probably the most affective prevention is not letting the soil dry up during the tuber development. Further, raise the organic matter level in the soil, so as to increase the water retention power of the soil. However, be careful not to over water the soil too much.
Controlling Soil pH
If you have sown mildly scab infected seeds, it is important to control the soil pH. Make sure that this level does not go above the 5.8 mark. It is better if it is lower than this. There are simple and affordable soil test kits available in the markets, which help you to detect the amount of pH in the soil.
Selecting Resistant Cultivars
Always choose more resistant cultivars in order to produce scabs free potatoes. Preferably, select from seeds likeAccent, Arran Pilot, Juliette, Golden Wonder etc. in order to get rid of common scabs. The russet skinned variety is more immune from the attack of the scabies than the other varieties.
Other than these measures, you can also rotate the root crop in order to prevent the scabies from spreading. Tilling a closed crop before tilling potatoes might also be a good idea