INTRODUCTION

The Potato belongs to the family Solanaceae. Potatoes are an important staple food crop. Annual world production of potatoes surpasses that of all other vegetables and ranks with wheat and rice. Introduced into Europe from Bolivia and Andes foothills in the 16th century by Spanish explorers, it is cultivated throughout the world including the Indo-Pakistan subcontinent. The potato is rich in starch and contains protein, minerals, & a fair amount of vitamins, particularly Vitamin - C.

Climate:

It is a cool season crop and is moderately frost - tolerant Temperature during the growing season has long been recognized as one of the most important factors influencing yield. Young plants grow best at a temperature of 240C; later growth is favored at 180C. Tuber production reaches a maximum at 200C, decreases with rise in temperature, and at about 300C tuber production stops entirely. Short days are beneficial for tuber production.

Soil& land preparation:

The potato develops best on deep, fertile, sandy lo clay loams with good water retention capacity. Because the potato has a relatively weak, shallow root system, impermeable layers in the soil limit rooting depth, which restricts water availability to the plant in dry. periods. Thus soil compaction can greatly reduce potato yields. Aeration of the soil has a great effect on the set and development of tubers.

Potato requires fine tilled light soil for proper growth of tubers. To obtain fine tilth for potato we should undertake one deep ploughing with soil turning plough followed by two cross harrowings or five to six ploughing with local plough. Planking should be done to make the field smooth and clod-free. If the soil did not have sufficient moisture during land preparation then fields are prepared after giving a pre-irrigation.

Manures and Fertilizers:

Potato has a high nutrient requirement; a yield of 25 tones of tubers/ha depletes the soil of 119 kg of N, 50 kg of P and 225 kg of K. In light soils and places where organic manures are not easily available, green manure is beneficial. Well rotted FYM at 30 t/ha should be incorporated into the soil three to four weeks before planting. Research on fertilizer requirements conducted in the Punjab and Sindh suggests that 100 kg N, 80-100 kg of P2O5, and 50 kg K2O per hectare are sufficient- to obtain good yields.

Spacing:

In hilly areas, potatoes are spaced at 60 x 30 cm and the tubers are planted in furrows. In the plains, however, they are planted on ridges spaced 30 cm apart; the distance between ridges is kept at 45-60 cm.

Seed Rate & Seed treatment

Potatoes are propagated by tubers, planted either whole or cut into pieces. . Whole potatoes with 3-5 cm diameter and at least 2-3 eyes, a weight of 20 grams or the same weight of cut potatoes to be used as seed To obtain maximum yields, healthy, disease-free tubers, free from mixture of other varieties, should he use. Seed rate depends on tuber size. The cut pieces should be cured at 10-150C and 85-95% relative humidity for 4-6 days. Before sowing seed should be properly treated with 1% thiourea (to break dormancy), light treatment (for sprouting of tubers) and suitable fungicide treatment.

Irrigation:

Irrigation is required within 7 days of planting. Then irrigation should be given at intervals of 3-4 days until first earthing up. After that irrigation should be given at intervals of 7-10 days until second earthing up. After second earthing up irrigation should be given in same way at intervals of 7-10 days. It should be very careful that irrigation water at any time should not more than 3/4th of the ridges. Irrigation should never heavy. In medium to heavy soil 3-4 irrigations shall be sufficient. In the other hand sandy soil having low water table, even 8-12 irrigations may be necessary. Time and number of irrigation may vary with the soil moisture status. Irrigation must be stopped 10-15 days before harvesting.

Weeding

Critical crop weed competition period is 25-50 DAS. The field should be free from weeds during this period. Manual, mechanical or different cultural weed control practices should be adopted. 2-3 hand hoeing help to suppress the weeds as well as loose the soil, increase soil aeration and enhance the growth of potatoes. Different botanical or myco-herbicides can also be used instead of synthetic chemical herbicides.

Important Diseases of Potato in West Bengal(ppt)
Harvesting

Crop becomes ready for harvesting when 50-70 % potato stems and leaves turn yellow colour. Potatoes should be harvested when the vines will be die. At least 15 days before harvesting green haulms of potato at the top of ground should be cut to allow the thickening of tuber skin, to increase the potato weight and to completely mature the tubers. Then mature tubers are harvested with the help of spade or country plough.

Post Harvest Management

After harvesting cut, rotted, diseased tubers should be discarded before sending it to the warehouse or cold storage. Clean and selected potato tubers should be stored in warehouse or cold storage for future use.