Potato

Climate and Soil : The crop is raised when maximum day temperature is below 300C and night temperature is not above 200C. Good crop growth is observed when days are sunny and nights are cool. Potato thrives well in cool climate. The highest tuberization is obtained when day and night temperature is 200C and 140C, respectively. Potato can be grown on different types of soils. Well drained, loose, friable, non-saline and non-alkaline loamy sand to sandy loam soils are suitable for this crop. Soil pH should be in the range of 5.5 – 8.0.

Improved Varieties :
Kufri Pukhraj (1998) : Plants are tall, vigorous and erect. It is an early bulking variety which gives economic yield quite comparable with Kufri Chandramukhi in 70 days. It is susceptible to late blight but escapes due to earliness. Its tubers are large uniform, oval, white with fleet eyes. It has dry matter content of 17-18 per cent. It yields 130 q/acre in 70-90 days.

Seed Rate : For autumn sowing 12-18 q/acre seed tubers of 40-50 g weight should be used for planting. Good quality and disease free seed should be used. The seed should be produced by using the seed plot technique. If the seed raised from autumn crop is to be used for spring planting, its dormancy should be broken by dipping cut tubers in a solution of 1% Thiourea and 1 ppm (one ml per 100 litres of water) Gibberellic Acid for an hour followed by air drying the treated tuber pieces for 24 hours in thin layers in shade.

Seed Potato Treatment and its Preparation : To control black scurf and common scab, treat the tubers with Tafasan or Emisan @ 2.5 g per litre of water for 10 minutes after taking out of the cold storage. The seed potatoes obtained from the cold store, cannot be planted immediately. It should first be dried with the help of blowers. Keep the treated tubers in a cool place/shade exposed in diffused sunlight for 8-10 days which initiates sprouting and helps the sprouts to become strong.

Time of Sowing : The best time for sowing is last week of September to mid-October for the autumn crop and the second fortnight of January for the spring crop. However, the date of sowing in September would much depend upon the temperature prevailing at that time.

Method of Planting : After the field has been prepared well, mark rows with a row marker. A ridger should be used for planting the crop manually. Semi-automatic or automatic planters are recommended where tractor power is available. The spacing between the rows should be 60 cm and between the tubers 20 cm. In south western districts, potato should be planted in two rows on 50-55 cm wide beds to get higher tuber yield and saving of water.

Manures and Fertilizers : Twenty tonnes of farmyard manure or green manuring alongwith 75 kg of N (165 kg of Urea), 25 kg of P2O5 (155kg of Single Superphosphate) and 25 kg of K2O (40 kg of Muriate of Potash) per acre should be used. Drill all P2O5 and K2O and half N at sowing and the remaining N at the time of earthing-up. Higher doses of these nutrients can be applied if the soil test shows low to very low status of these nutrients. Note: Application of N fertilizer more than recommended is no substitute for farm yard manure or green manure. Earthing-up : A double mould board plough or a ridger should be used for earthing up after 25-30 days of sowing.

Seed Plot Technique : This technique aims at raising a healthy seed crop of potato in Punjab during the period of low aphid incidence. This pest is responsible for transmitting the viral diseases, like leafroll, PVX, PVY and PVA. For the seed crop, healthy seed potato, free from viral infection should be obtained and planted in autumn i.e. in the first week of October. Sowing at a spacing of 50 x 15 cm would ensure the development of a large percentage of seed size tubers. An acre of the seed crop will produce enough seed for planting of 8 to 10 acres of the crop. Normal plant protection measures should be adopted to control aphids and other insect pests. Rogue out otherwise unhealthy plants noticed during the growing season to ensure the production for better quality seed. Towards mid-December, irrigation may be restricted and later withheld completely so that the haulms wilt and fall down. As soon as there are 20 aphids per 100 leaves, cut the haulms. Allow the tubers to mature in soil for about 15 days. The harvested crop may be graded and transferred to cold storage for planting in the following autumn season.