Since potato is neither an indigenous crop – it was introduced from Europe – nor ideally suited for cultivation under Indian conditions, the production of its good quality seeds has been posing formidable problems. Till around the 1960s, potato seeds (small, disease-free tubers for planting fresh crop) were either imported or grown in hills. However, the exotic seeds, produced in areas having cold climate and long days, could not perform to their potential in India, where the days are relatively shorter during the potato-growing season. The supply of seeds from the hills, on the other hand, was too meagre to allow any appreciable extension of area planted under this crop. These constraints made it imperative for the potato scientists to evolve innovative and indigenous methods to produce good quality mini potato tubers in the plains for use as seeds.
The first significant breakthrough in this regard came in the mid-1960s with the development of the “seed plot technique” by the Jalandhar station of the Central Potato Research Institute (CPRI), Shimla. This technique involved raising seed crop during a period when the population of aphids (carriers of various diseases) was low and taking up regular pest-control measures. Besides, unwanted and diseased plants were uprooted manually to stave off seed-borne infections. This method helped in increasing the potato seed supply considerably. The other notable technical advances in potato seed production included the development of technology for producing “true potato seeds” – the botanical seed that the potato plant occasionally bears after flowering – and in-vitro production of disease-free plantlets in test tubes through tissue culture.
The latest instance in the unceasing endeavour to improvise seed production systems is the standardisation of indigenous mechanism for producing mini seed tubers through the aeroponics technique. Since such methods developed and commercialised abroad are mostly patent-protected, CPRI had to evolve its own mechanism for this purpose. Its efforts have, of course, been supported by the Lima (Peru)-based International Potato Centre (Centro Internacional de La Papa).
According to CPRI scientists, the new system yields several times more seed tubers than most of the available techniques. It also requires 90 per cent less water and 50 per cent less nutrients compared to traditional seed production methods. Being efficient and cost-effective, this technology is expected to help meet the requirement of potato seeds to meet the growing consumption demand.
A prototype of the aeroponics unit devised at CPRI consists of an electric unit, two dark growth chambers, a nutrient solution chamber, a high pressure pump and spray nozzles. The potato plantlets are hung in the growth chambers where the nutrient-enriched water is sprayed on them in the form of a fine mist at fixed intervals. The root system starts developing in about a week and harvesting of seed tubers can begin from about 60 to 65 days. On an average, about 30 to 35 mini tubers can be obtained from a single plant in this system, as against just eight to 10 in the case of conventional methods.
To facilitate its rapid spread, CPRI has licensed this technology to five commercial enterprises. Two of these will be engaged in fabricating and installing the equipment, while the other three will produce the seed tubers for sale to potato growers. Several other entrepreneurs are also said to be in touch with CPRI to seek licences for commercialising this technology.
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