Plant protection in organic cultivation of potatoes can be a hard task for an organic potato farmer. Colorado potato beetle, the most important insect pest of potatoes worldwide, can be controlled by using the following techniques: organic soil management, lower fertilizer rates, treatment with spinosad, an insecticide based on chemical compounds found in the bacterial species Saccharopolyspora spinosa, no-till soil management, straw mulching and crop rotation. Colorado potato beetle has the ability to evolve resistance to a wide variety of chemicals. Variety choice has a significant effect on tuber losses caused by wireworms. Protection of potatoes against disease damage involves preventive measures, appropriate regulation strategies and optimum spraying techniques. Planting early in the cropping season and using short vegetation period varieties help to avoid early incidence and high disease severity from potato viruses. Plant growth promoting and biological control bacteria, such as Bacillus spp. and/or Pseudomonas fluorescens, are being used by potato growers as seed coatings and soil application to manage diseases. Organic amendments, such as soil application of composts, green manure, farmyard manure, oilcakes and crop rotation, can be used to suppress soil-borne pathogens. Weed control options include mulching and ridge cultivation. Choice of appropriate varieties can reduce damage; recommended are those with stronger roots to allow greater uptake of nutrients from soils, good physiological characteristics, such as suitability for local conditions, hardiness to stress factors and good storability, a short vegetation period (earlier varieties) with quick initial development of leaves to cover furrows and compete better with weeds, high and constant resistance to diseases, and good quality and quantity of tubers.
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You can find more information in the book:
Olle, M. 2016. Organic cultivation of vegetables and potatoes. USA: CreateSpace Independent Publishing Platform, (in English) 132 pp.
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