पठार क्षेत्रों और दक्षिणी पहाड़ियों के लिए आलू की उत्पादन तकनीक

Potato is a cool season crop. Its wider adaptability makes it possible to grow this crop in almost all the states of the country but by adopting suitable production technology.

The plateau area and southern hills, which represent a sizeable area under potato cultivation differ from other parts of the country with respect to climatic and soil conditions, in which major potato growing area lies. Hence, for exploiting the potential benefits, the farmers of this region need to adopt suitable technology for cultivating potato, which are discussed in detail in this paper.

In India major potato area is concentrated in Northern plains (80 – 85%). The hilly areas of northern India accounts for 6-7 per cent and plateau areas of the country represents about 8 to 9 per cent area. The remaining area is present in problematic areas like Nilgiri and Palani hills of Tamil Nadu and Sikkim and North Bengal hills. In these different parts of the subcontinent potato is grown under different climatic and soil conditions which define the technology to produce good harvests of potatoes. Hence, adoption of appropriate technology suitable for the conditions makes it possible to realize the fullest benefits from the crop. 

Potato in Plateau Region:

The plateau region in our country covers the areas of central and peninsular India and it is situated between 600 and 1000m altitude. The states of Gujarat, Madhya Pradesh, Maharashtra, Chotanagpur, Karnataka, Andhra Pradesh and Orissa comprise the plateau region. Here potato is grown under different situation as compared to that of other major potato growing areas of the country.

In this area two crops of potato are grown viz., kharif and rabi. High minimum temperature and erratic rainfall are the major problems in kharif season. Conversely rabi crop is grown during winter i..e, from November to February under irrigated conditions. Short growing season, high temperatures after January and potato tuber moth are the important problems in this season.

The soils of this zone are red sandy or fine textured black. The average temperatures are higher than those in the North Indian plains.

Southern hills:

The Nilgiri and Palani hills of Tamil Nadu contribute to potato cultivation under Southern hills and the crop is grown in an area of about 3000 ha in these hills. The climatic condition of these hills is such that three crops of potato can be taken up easily per year by growing summer (60-65% area) and autumn (25 – 30% area) season crops under rainfed conditions and spring crop (5-10% area) under irrigated conditions.

Crop growth conditions differ from season to season which will have direct correlation with the technology to be adopted during different seasons. During summer season the crop is grown under long day conditions which prolong the length of growing period and accordingly the schedule of various cultural practices are to be planned. Ill distribution of rainfall, late blight and potato cyst nematodes are the major problems of this region.

Cultural practices for potato in plateau region and Southern hills:

Plateau region covers about 8-9 percent of potato area and 6-7 percent of potato production in the country. Karnataka occupies maximum area with lowest productivity in this zone and the highest potato productivity is observed in Gujarat state.

Triennial averages (2002-03 to 2004-05) for potato area, production and productivity in plateau region

(*The values in parentheses represent the percentage to All India values)

The Southern hills which consists of Nilgiri and Palani hills account for a meager area of 3000 ha but with an average yield of 16.6 t/ha.

Land preparation:

Potato grows well in slightly acidic soils with friable structure. The land is to be prepared well with 2-3 ploughings and then harrowing. Farm Yard Manure has to be applied @ 15 to 20 tonnes per hectare depending upon the fertility status and it has to be thoroughly mixed up with the soil.

Selection of seed material:

Seed tubers are to be procured from a reliable source which are well sprouted and are about 40 to 60 g in size. The seeds can be treated with mancozeb (0.3%) or boric acid (3%) to avoid tuber borne and soil borne diseases.

Planting time of Potato:

Potato is grown as winter crop in central plains of Gujarat, Madhya Pradesh and Orissa. Here the optimum time of planting is Ocotber/ November.

In Deccan plateau, i.e., Maharashtra, Andhra Pradesh and Karnataka, two crops of potato can be grown, i.e., Kharif crop can be planted from mid June to middle of July and the  Rabi crop can be planted during October/ November.

In Southern hills it can be grown through out the year under three different seasons viz., summer (April/May), autumn (August/September) and spring (January).

Varieties:

The suitable varieties for different regions are given below.

Spacing:

Spacing differs from season to season. During kharif season 60 x 20 cm under rainfed condition and during rabi 45 x 20 cm under irrigated conditions is found to be optimum. In Southern hills, summer crop can be planted at a spacing of 60 x 20 cm and autumn and spring can be planted at a spacing of 50 x 20 cm.

Manures and fertilizers:

Potato crop giving 40 tonnes of tubers per hectare removes 175 kg N, 80 kg P₂O₅ and 310 kg of K₂O. The recommended doses of fertilizers are given in the following table.

Source of fertilizers:

Among the sources of nitrogenous fertilizers, combination of ammonical and nitrate forms like Calcium Ammonium Nitrate (CAN) is more suitable and it is followed by ammonical forms.

Urea is less efficient when compared with other forms. Similarly phosphorus in the form of Single super phosphate alone or in combination with rock phosphate in 1:1 ratio suits well for potato. With respect to potassium, sulphate form is more suitable than chloride form as it has great influence on quality of potato tubers.

Method and time of application of fertilizers:

In plateau area, entire dose of phosphorus and potassium along with 50% of recommended nitrogen can be applied as basal dose and the remaining nitrogen can be applied at the time of earthing up.

The fertilizers are to be mixed as per the recommendation and the mixture is to be applied in the furrows just below the seed tubers either manually or mechanically with the help of tractor mounted fertilizer drill. In southern hills entire dose of fertilizers can be applied in furrows at the time of planting as basal application.

Interculture:

Interculture is done for destroying the weeds and to keep the soil loose and to cover the tubers well with soil in potato fields.

Hoeing:

A light hoeing is to be done 10 to 15 days after germination to make the soil loose by breaking the crust and to kill the weeds.

Weed control in Potato crop:

For controlling the weeds in potato field, preplanting application of Fluchloralin @ 0.7 to 1.0 kg/ha is very effective. Depending upon the intensity of weed growth a pre-emergence application of alachlor @ 1.0 to 1.5 kg/ha also is recommended. For post emergence control of weeds paraquat @ 2.0 to 2.5 l/ha at 3-5 % emergence of potato crop can completely keep the potato weeds under control.

Earthing Up:

The potato haulms are to be earthed up to cover the growing stolons and developing tubers. Generally one earthing up is enough when the crop is 15 – 20 cm tall and just starts stolon formation. Depending upon the variety and duration of the crop, a second earthing up can also be done for properly covering the tubers.

Earthing up is done with the help of spade or ridge plough and this operation should be completed timely as it will have direct bearing on the final tuber yield. In southern hills earthing up is to be done at 45 days after germination using Kothu, a fork like tool.

Irrigation:

Kharif crop grown in Deccan plateau area does not require any irrigation as it is grown during Southwest monsoon season. Rabi and winter crops are to be irrigated as the rainfall received is not enough during this season.

On an average potato crop requires 70 cm irrigation water. Stolon formation and elongation are the critical stages (20-40 days) in potato. First irrigation should be light and given 4-7 days after planting.

The subsequent irrigation should be given at an interval of 5-7 days in September-October, at 7-10 days interval in November, 10-15 days interval in December and at 5-7 days interval in January to March and onwards. Irrigation is to be given in furrows which may be filled to about three fourth of depth. In southern hills, summer and autumn crops do not require any irrigation. Spring crop is to be irrigated at an interval of 6-7 days.

Drinage:

The potato field should have a provision for good surface drainage of water as the crop is very sensitive to untimely rains and excess water.

Plant protection:

In Plateau region:

Early blight, late blight, brown rot or bacterial wilt, common scab, black scurf, viruses, aphids and tuber moth are the major plant protection problems in plateau region.

For the control of white grubs, jassids, leaf hopper and other sucking pests, phorate 10G can be applied @ 10 kg/ha at the time of planting and the same should be repeated at the time of earthing up to control the aphids.

For the control of cutworms and Spodoptera litura, spray chloropyriphos @ 0.25% by covering all the plant parts fully with the spray solution. 

For the control of early and late blight, spraying contact fungicide like mancozeb @ 2kg per 800 litres of water per hectare at 40 days and repeating it at an interval of 10-15 days is effective. In case of persistence of the disease, spraying of systemic fungicide containing either metalaxyl (Ridomil @ 2.0 kg/ha) or cyamoxinil (Curzate @ 1.5 kg/ha) alternating with mancozeb is resorted to.

Bacterial wilt which is a major problem especially in Hassan, Bangalore and Kolar areas of Karnataka can be kept under control by following :

• Crop rotation with non solanaceous crops like fingermillet, maize etc.
• Fallow ploughing
• Applying bleaching powder @ 6-8 kg/ha
• Use of disease free seeds

Black scurf can be controlled by soil treatment with PCNB (Penta Chloro Nitrobenzene) dust @ 50 kg/ha. Treating the seed tubers with 3% boric acid solution for 30 minutes is beneficial to control most of the soil and tuber borne diseases.

In Southern hills:

Here, cyst nematodes and late blight are the major plant protection problems.

To keep the nematode population under control, a basal dose of Furadan 3G @ 65 kg/ha is to be applied in the furrows. Crop rotation with non-solanaceous crops like cabbage, radish and carrot has to be followed.

For the control of late blight, spraying systemic fungicide containing either metalaxyl (Ridomil @ 2.0 kg/ha) or cyamoxinil (Curzate @ 1.5 kg /ha) compound is to be adopted when the weather condition (high RH and less sunshine hours) becomes favourable for the disease development. This has to be followed by spraying of contact fungicide like mancozeb @ 2kg per 800 litres of water per hectare is to be adopted at an interval of 7-8 days. After that depending upon the weather condition, spraying of contact fungicide is to be continued at an interval of 7-10 days and if disease symptoms are observed, an intermittent application of systemic fungicide after every two sprays of contact fungicide is recommended.

Crop rotation:

Potato crop should not be grown continuously in the same field. Rotating it with non-solanaceous crops is recommended. In plateau region, crops like pearl millet, jowar, pulses, onion, sunflower, sugarcane, vegetables like French beans, cluster beans can be grown in rotation with potato either in kharif or rabi season depending upon the season in which potato is grown. In southern hills potato can be rotated with cole crops like cabbage, carrot, radish and French beans.

Harvesting:

In plateau region, potatoes are harvested either at their full maturity or little earlier depending upon the market price, manually using Khurpi, a hand hoe or using potato digger i.e., animal drawn or tractor mounted. Then the tubers are to be kept in heaps for 10-15 days for curing and after that they can be graded and sent to the market. In southern hills potatoes can be harvested at their full maturity with the help of kothu, and they can be graded and sent to the market.

Storage of Potato:

In plateau region, under indigenous methods, potatoes can be stored either in room storage or pit or heap method of storage. The seed as well as table potatoes can also be stored in cold stores at controlled temperatures. In southern hills farmers usually do not store their produce as they tend to sell entire quantity of potatoes because of prevailing market rates at the time of harvest. However, they can be stored in wooden racks under diffused light conditions.

Authors:

K.Manorama*, G.Ravichandran and S.S.Lal