Cultivation of Sweet Potato ( Sakharkanda) ; A complete Information Guide

February 27, 2021 Agrovista

Cultivation of Sweet Potato ( Sakharkanda) ; A Complete Information Guide

Sweet Potato (Ipomoea batatas Lam) belongs to the family Convolvulaceae, popularly known as “sakharkanda” in India. Sweet Potato is an important tuber crop in tropical and sub-tropical countries like Africa, China, the U.S.A., and India. In India, sweet potato is mainly cultivated in Bihar, Uttar Pradesh, West Bengal, Tamil Nadu, Maharashtra, and Punjab.

Table of Contents

It is mainly used for human consumption and the preparation of starch and alcohol. It is used as a popular vegetable in some parts of India. The vines of sweet potato are excellent fodder for cattle. It is a subsidiary food crop and an efficient caloric supplier.

Sweet potato is native to the tropics of America. It was probably introduced by the Portuguese in India.

Flowering Field of Sweet Potato

Nutritive Value of Sweet Potato;

The nutritive value of sweet potato in 100 gms of the edible portion is given below ;

Nutrient	Value	Nutrient	Value
Moisture	68.5 g	Manisum	12 mg
Protein	1.8 g	Chlorine	85 mg
Fat	0.7 g	Vitamin A	7700 IU
Fibre	1.0 g	Vitamin B group	0.46
Carbohydrate	27.8 g	Vitamin C	22 mg
Calcium	30 g	Vitamin E	40 mg
Phosphorus	49 g	Pantothenic	0.93 mg
Iron	0.7 g	Nicotinic acid	0.46 mg
Sulphur	15 g	Vitamin C	22 mg
Potassium	530g

Its food and vitamin value can be compared with that of rice. Sweet potato is good for stepping food production and it contains starch which varies from 19-32 %

Climatic Conditions Required for Sweet Potato Cultivation;

Sweet potato is a tropical and subtropical crop and requires a long warm growing season. Plenty of sunshine and moderate rainfall (75-150 cms.) with Warm nights and days for four months are best suited for it. It is a drought-resistant vegetable. But it does not stand frost.

Soil and its preparation for Sweet Potato Cultivation;

Sweet potatoes can be grown on a wide range of soils. But light soils are invariably regarded as suitable for sweet potatoes. Sweet potato prefers moderately acid Soil. The optimum PH range is 5.8 to 6.7.
The land should be well prepared and of good tilth for sowing sweet potato, 4-5 ploughings should be given to prepare a good tilth. After ploughing, planking is essential to make soil pulverized and leveled. Heptaf-5-D @ 810 kg per acre or Aldrin or Chlorodane 5 %t @ 10-15 kg per acre should be applied with the last preparatory tillage to check the Soil pests.

Important Varieties of Sweet Potato

Sweet potato varieties are divided into two groups according to tuber color, viz. (i) Red skin and (ii) White skin. The following are the important ;

Variety	Characteristics
Punjab Sweet Potato-21	The vines of this variety are medium-long in length.. It has deep red color tubers with white flesh It is 20cm long and 4cm wide. The variety matures within 145 days. The average weight of the tuber is 75g. The tuber contains 35% dry matter and 81mg/g of starch. It gives an average yield of 75 qtl/acre.
Varsha	It is recommended to grow in Maharashtra. It is suitable for growing in the rainy season. It gives an average yield of 62.5 q/acre.
Konkan Ashwini	This variety was developed for cultivation in Maharashtra. It is a short-duration crop and gives a high yield.
Sree Arun	It is an early maturing variety with pink color skin and cream color flesh. Developed by the Central Tuber Crop Research Institute (CTCRI), Sreekariyam. It gives an average yield of 83-116 qtl/acre.
Sree Kanaka	The variety is developed by Central Tuber Crop Research Institute (CTCRI), Sreekariyam. It has a cream-colored skin tuber, with dark orange color inner flesh. It gives an average yield of 41-62.5 qtl/acre.
Sree Varun	The variety is developed by Central Tuber Crop Research Institute (CTCRI), Sreekariyam. It contains a cream-colored skin of the tuber. It is an early maturing variety Days to Maturity 90-100 days. It gives an average yield of 80-110 qtl/acre.

H- 268, Pusa Safed, Pusa red, Pusa sunahari, NO- 4004, S- 30, Klamath and recent one Skarkand – 5. Days to maturity of all the major varieties ranges between 90- 140 days. In general, it is ready for harvesting in 120 days.

Planting time of the Sweet Potato Crop;

The Planting time varies considerably in different parts of the country. viz.
North India – March or June-July

South India – September, October

Central India – October-November

Eastern India – May-July and September

Method of Planting of Sweet Potato Planting ;
Vine cuttings or tuber slips can be used to propagate sweet potatoes. Propagation by vine cuttings is a common practice. The cuttings are grown in the nursery from the old vines or slips produced on the tubers planted in the nursery bed. The vine cuttings are planted on ridges for monsoon crops or in flatbeds in low-rainfall areas.

Terminal cuttings from full-grown plants are reported to give better growth and yield than basal or middle cuttings. Each cutting should have at least four nodes.

The vine cuttings are planted about 60 cm from row to row and 30 cm within the row. Keeping the endbud free. Roots are formed in the central part of vines that are put inside the soil.

Seed Rate of Sweet Potato ;

About 10-20 thousand cuttings are required for planting an acre of land. 160-200 kg of tubers give enough slips to plant an acre. For one acre of planting, a nursery of 1/10th acre is required for producing slips.

Manuring in Sweet Potato Crop ;

Sweet potato responds well to manuring. A sweet potato crop yielding 15 tonnes per hectare removed from the soil about 70 kg of N, 20 kg of Phosphoric acid, and 110 kg of potassium per hectare

A mixture of 40 kg Nitrogen, 40 kg Phosphoric acid, and 40 kg potassium per acre gives a good response. Full quantity of phosphoric acid, potassium, and half of nitrogen should be applied at the time of planting. Apply the remaining half of the nitrogen as a top dressing during earthing up.

Intercultural operation in the Sweet Potato Crop ;

Hoeing and weeding are done to control the weeds and to make the soil loose and friable. This operation should continue till the vines spread and cover the field. The application of amiben (Chloromben) @ 3 kg a.i. per hectare after transplanting and Eptam (EPTC) @ 1.5 and 3.0 kg a.i. per hectare incorporated before transplanting gave fair to good weed control and caused little or no injury to sweet potato crops
The crop planted on ridges is earthed up when the crop is about two and a half months old.

Irrigation Requirement in Sweet Potato Crop ;

The water requirement of this crop is about 30 acres. Sweet potato is generally cultivated as a rainfed crop in Eastern India. In the absence of rainfall, the crop should be irrigated frequently to get a good crop.

Insect and Pest Management in Sweet Potato

a) Insects Manement in Sweet Potao ;
1. Sweet Potato Weevil
Sweet Potato Weevil is the most serious pest of this crop. A red and blue ant-like weevil that makes holes in the stem and tubers. The pale yellow grub of this pest, having no feet, bores into the vines.
Control Measures
1) Cultural practices such as the destruction of alternate hosts, removal of infested vines and tubers, deep ploughing of the land after harvest, and earthing up to prevent the entry of Weevils into tubers have been found effective for controlling this pest.
2) This post can be controlled by dipping planting material in a solution of an insecticide (such as carbofuran or diazinon) for 10-15 minutes before planting can control sweet potato weevils for the first few months of the growing season. Dipping longer than necessary can burn and kill the planting materials
2. Sweet Potato Sphinx
It is a serious leaf-eating caterpillar of sweet potato. A stout long non-caterpillar that completely defoliates the plants.
Control Measures
1) Hand-picking and destroying the caterpillar is the best my infestation is less.
(ii) This post can effectively be controlled by spraying lead arsenate
b)Diseases Management in Sweet Potato

1. Leaf Spot;
Large brown spots appear on the leaves.

Control Measures: This disease can be controlled by spraying with Zineb (Dithane Z-78) or Mancozeb (Dithane M-45) @ 2.5 gm per liter of water at an interval of 15 days.

2. Black Rot
It is primarily a storage rot of tubers but may also occur in the field. Infected foliage become yellow and sickly in appearance. Black canker is seen on the underground portions and grey black circular spots occur on fleshy roots.
Control Measures;

1) Careful sorting of tubers before storage and rotation of crops help reduce the incidence of the disease.
(ii) The seed tubers should be treated with mercuric chloride solution (1 in 1000) or 2.5 percent borax solution.

3. Soft rot
Storage rot of tubers and their tissue become soft and stringy.

Control Measures
1) Avoiding bruising and injuring the tubers at harvesting is the best method of controlling this disease.
2) The walls and floors of the storage room should be disinfected before storing the tubers.

Harvesting of Sweet Potato Crop;

Sweet potato becomes ready for harvesting from 105 to 150 days after planting. Sweet potato is harvested when the leaves turn pale and later turn slightly yellow and the culm surface dries up quickly and does not turn black as that of immature tubers. The vines are removed by cutting, and then harvesting of tubers is done with the help of a spade. The green vines may be fed to the cattle.

The yield of the Sweet Potato ;
The average yield of sweet potatoes is about 80-100 quintals per acre. The yield varies with the variety, method of cultivation, and region.
Storage of Sweet Potato;
Sweet potatoes should be stored in well-ventilated godowns after curing properly. The quality of cured tubers was markedly superior to that of uncured tubers. It is recommended to cure the tubers for one week at 29°C and to store them at 13°C to 15°C with 85-90 percent relative humidity at all times

Explore Further;

Cultivation of Potato in India