Potato

Crop Establishment

Seed Selection Sowing Methods Intercultivation

Seeds and Sowing

Selection of the seed stock

  • Potato is vgetatively propagated, hence the disease pathogens are carried from the mother plants and the crop gets spoiled.
  • Therefore, pure and healthy seed is the basic necessity for successful cultivation of the crop.
  • Following points must be taken into account at the time of seed selection:
    1. Seed tuber must be uniform in shape and size.
    2. The tubers showing surface diseases like wart, scab, brown rot and nematode infection must be separated out.
    3. The tubers should not be shriveled.
    4. The tubers should be in their right stage of sprouting.
    5. The sprouts should be about 1 cm long at the time of sowing.
    6. The tuber size should be preferably 3.5 to 5 cm in diameter.
    7. The seed tubers should be purchased from a trusted agency like State Department of Agriculture, etc.

Selection of seed tubers

  • Use of certified and disease free tubers is important.
  • Tubers produced in rainy season should not be used for sowing in winter season.
  • Each tuber should have 2-3 eye buds and large sized tubers should be cut into pieces that weighs around 40 to 50 g.
  • Small sized tubers weighing 25 g can be used without cutting.
  • Knife for cutting should be dipped in alcohol or spirit or formalin 10 per cent solution after every cutting so as to avoid spread of seed borne diseases.
  • The cut tubers are then dipped in 1 litre solution of mancozeb (4 g) or mercuric compound (2.5 g) or kaptafol (2 g) for five minutes, dried in shade and then can be used for sowing.
  • By this we can avoid seed tuber rotting.
  • Tubers should not be used for sowing just after taking out from cold store but they must be spread in cool, shady and ventilated place having diffused light for accelerating the sprouting of tubers as sprouted tubers give higher yield than unsprouted ones.

Sowing time

  • The optimum time of planting potato synchronizes with the period when maximum temperature is about 30°- 32°C and minimum around 18°- 20° C.
  • The planting period is explained as follows:

Sowing time

  • In Karnataka, as a rainfed crop, it is sown during the month of May and June i.e., as soon as first showers of monsoon are received.
  • As a irrigated crop, it is grown in winter season during November-December.

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Seed size, spacing and seed rate

  • The ideal tuber size for planting should be 2.5 to 3 cm in diameter and approximately 50 g in weight.
  • It is an established fact that potato yield increases with increase in seed size and decrease in spacing.

  • However, the seed size and spacing depend upon the variety and the purpose for which the potato is grown.
  • Higher seed rates are used for raising a good crop but lower (preferably cut pieces) for ware potatoes.
  • A correlation of all these factors is given below:

seed Dia Spacing Seed Rate
2.5 cm x 3.0 cm 45 cm x 15 cm 10 qt/ha
4.0 cm x 5.0 cm 50 cm x 20 cm 25 qt/ha
2.5 cm x 4.0 cm 60 cm x 25 cm 20 qt/ha

Method of planting potato

  • Furrows of 40-50 cm should be opened. Apply 50 per cent of recommended dose of nitrogen, full dose of recommended phosphorus and potassic fertilizers 10 cm away from both furrow and tubers.
  • Then place the tubers at an interval of 20 cm.
  • Provide light irrigation immediately after sowing.

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Intercultivation and Earthing

  • Potato tubers are modified under ground stems which use to synthesize anthocyanin and chlorophyll if exposed to sunlight, therefore, it is essential to cover the tubers fully with soil because with chlorophyll formation the tubers stop accumulation of starch and remain smaller and the solanin formation in green tubers results into bitter taste of tubers which is harmful, if consumed.

  • Number of earthling and height of ridges after earthling depends upon method of planting and soil type.


  • In case of flat bed planting two earthings - one at 25-35 days and second 45-50 days after sowing are given.
  • In case of furrow planting method light ridging is done up to the height of 10-15 cm soon after sowing and second earthing is done about 30-35 days after sowing.
  • While earthing it is essential to loosen the soil around the plants, then fertilizer, needed for top dressing, is mixed with the soil after which the ridges are made.
  • Since the roots are disturbed and partly damaged it is required to provide one very light irrigation.

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Karnataka