Pantnagar Bioplant Tech - Turmeric Crops

Production Technology of Turmeric

Turmeric (Curcuma longa), the ancient and sacred spice of India is a major rhizomatous spice produced and exported from India. Turmeric is used as condiment, dye, drug and cosmetic in addition to its use in religious ceremonies. India is the leading producer, consumer and exporter of turmeric in the world.

Climate and Soil

Turmeric can be grown in diverse tropical conditions from sea level to 1500m above MSL, at temperature range of 20-30C with a rainfall of 1500 mm or more per annum, or under irrigated conditions. It is grown on different types of soils from light black, ashy loam and red soils clay loam's. However, it thrives the best in a well-drained sandy or clayey loam.

Varieties

A number of varieties are available in the country and are known mostly by name of locality where they are cultivated. Popular varieties are Duggirala, Sugandham, etc., Among the clonal selections Suguna, Sudarshana and Suvama yielding 25-35 tonnes/hectare and IISR prabha with a curcumin content of 6.52 are important.

Preparation of land

The land is prepared with the receipt of early monsoon in May. The soil is brought to a fine filth by giving about four deep ploughings. Weeds, stubbles, roots etc. are removed. Immediately with the receipt of pre-monsoon showers, beds of 1-1.5 m width, 15 cm height and of convenient length are prepared with spacing of 50 cm between beds. Planting is also done by forming ridges and furrows.




Planting

Turmeric can be planted during April-May with the receipt of premonsoon showers.

Seed materials

Whole or split mother rhizomes are used for planting. Well developed healthy and disease free rhizomes are to be selected. Rhizomes are treated with 0.3% Dithane M-45 and 0.5% Malathion for 30 minutes before sowing. Small pits are made with a hand hoe in the beds in rows with a spacing of 25 cm x 30 cm and covered with soil or dry powdered cattle manure. The optimum spacing in furrows and ridges is 45-60 cm between rows and 25 cm between plants. A seed rate of 2,500 Kg of rhizomes is required for planting one hectare.

Manuring

Cattle manure or compost at the rate of 40 tonnes per hectare is applied by broadcasting and ploughing at the time of preparation of land or as basal dressing by spreading over the beds to cover the seed pits after planting. Fertilizers at the rate of 30 Kg N, 30 Kg P205 and 60 Kg K20 per hectare are to be applied in three splits . In areas low in major nutrient status fertilizer rate to be applied is @ 60 kg N, 50 kg P205 and 120 kg K20. The beds are to be earthed up, after each top dressing with the fertilizers.

Mulching

The crop is to be mulched immediately after planting with green leaves at the rate of 12-15 tonnes per hectare. It may be repeated for a second time after 50 days with the same quantity of green leaves after weeding and application of fertilizers.

After Cultivation and growing as intercrop

Weeding may be done thrice at 60, 120 and 150 days after planting depending upon weed intensity. Turmeric can be raised as a mixed crop with chillies, colocasia, onion, brinjal and cereals like maize, ragi etc.

In the case of irrigated crop, depending upon the weather and the soil conditions, about 15 to 20 irrigations, are to be given in clayey soils and 40 irrigations in sandy loams.

Plant Protection

Insect Pests

Shoot borer (Conogethes putictiferalis)

The shoot borer is the most important pest of turmeric. The larvae bore into the pseudostems and feed on the growing shoot resulting in yellowing and drying of the infested shoots. The presence of bore hole on the pseudostem through which the frass is extruded and the withered central shoot are the symptoms of pest infestation. Adults are small moths with orange wings with minute black spots. Fully grown larvae are light brown.

Control : Spraying of malathion 0.l% or monocrotophos 0.05% or Dipel(0.3%) (Bacillus thuringiensis product) during July-October at 21 day intervals is effective against the pest.

Leaf roller (Udaspes folus)

The larvae of the leaf roller cut and fold the leaves and remain within and feed on them. Adults are medium sized butter flies with brownish black wings with large white spots. Fully grown larvae are dark green.

Control : Spraying with carbaryl 0.1% may be undertaken in case the infestation is severe.

Rhizome scale (Aspidiella bartii)

The rhizomes scales infest rhizome in the field and in storage. They feed on the plant sap and in the field in severe cases of infestation, the plants wither and dry. In storage the pest infestation results in shriveling of buds and rhizomes and may also affect the sprouting of rhizomes. The adult female scales are minute, circular and light brown to grey and appear as encrustations on the rhizomes.

Control: The pest can be controlled by discarding severely infested rhizomes and by dipping the seed rhizomes in quinalphos 0.075% twice prior to storage and sowing.

Diseases:

Leaf blotch

The disease is caused by Tapbrina maculans. The disease appears as small, oval, rectangular or irregular brown spots on either side of the leaves, they soon become dirty yellow or dark brown. The leaves also turn yellow. The yield goes down considerably. in severe cases the plants present a scorched up appearance. The disease can be controlled by spraying the plants with 0.2% Dithane M-45.

Leaf spot (Colletotriclium capsici)

The symptoms appear as brown spots of different sizes on the upper surface of the young leaves. The spots are oval, whitish or greyish in centre, Later two or more spots may coalesce and form an irregular patch covering almost the whole leaf. The affected leaves eventually dry up. The rhizomes do not develop well. The disease can be controlled by spraying the plants with 0.3% Zineb or 1% Bordeaux mixture.

Rhizome rot:

The disease is caused by Pythium graminicolum starting from the margins, the leaves get dried up. Collar region of the pseudostems becomes soft and water soaked, and the plant collapses. Dip the rhizomes in 0.3% Dithane M-45 solution for 30 minutes prior to storage and at the time of sowing prevents the disease. When the disease is noticed in the field, the beds should be drenched with 0.3% Dithane M-45 or 0.3% cheshunt compound.

Harvesting:

Depending upon the variety, the crop becomes ready for harvest in seven to nine months, Usually it extends from January-March. Early varieties mature in 7-8 months, medium varieties in 8-9 months and late varieties after 9 months.
Usually the land is ploughed and the rhizomes are gathered by hand picking or the clumps are carefully lifted with a spade. Harvested rhizomes are cleaned of mud and other extraneous matter adhering to them. The average yield per hectare comes to 20-25 tonnes of green turmeric.

Processing:

Curing:

Fingers are separated from mother rhizomes. Mother rhizomes are usually kept as seed material. The fresh turmeric is cured for obtaining dry turmeric. Curing involves boiling of fresh rhizomes in water and drying in the sun.

The traditional method of curing:

The cleaned rhizomes are boiled in copper or galvanized iron or earthen vessels, with water just enough to soak them. Boiling is stopped when froth comes out and white fumes appear jigging out a typical odor. The boiling lasts for 45-60 minutes when the rhizomes are soft. The stage at which boiling is stopped largely influences the colour and and aroma of the final product. Over cooking spoils the colour of the final product while undercooking renders the dried product brittle.

The improved scientific method of curing turmeric :

The cleaned fingers/mother rhizomes are taken in perforated trough made of G1 or MS sheet with extended parallel handle. (A medium type trough of size 0.90 x 0.40 in can hold about 50 kg of raw turmeric). The perforated trough containing the raw turmeric are then immersed in a pan with water which can hold 3-4 toughs at the same time. Boil it till the fingers/mother rhizomes become soft. The cooked turmeric is taken out of the pan by lifting the trough and draining the water into pan itself. The same hot water in the pan can be used for boiling next set of raw turmeric, which are already filled in troughs. The cooking of turmeric is to be done within 2-3 days after harvest.

The rhizomes may also be placed in baskets with perforated bottom and sides, and then dipped in covered tanks when the quantity is large or may be put directly into the vessels when the quantity is small. The mother rhizomes and the fingers are generally cured separately.

Drying :

The cooked fingers are dried in the sun by spreading in 5-7 cm thick layers on bamboo mats or drying floor. A thinner layer is not desirable, as the colour of the dried product may be adversely affected. During night time, the material should be heaped or covered. It may take 1015 days for the rhizomes to become completely dry. Artificial drying, using cross-flow hot air at a maximum temperature of 60'C is also found to give a satisfactory product. In the case of sliced turmeric, artificial drying had clear advantages in giving brighter coloured product than sun drying which tends to suffer surface bleaching. The yield of the dry product varies from 20-30% depending upon the variety and the location where the crop is grown.

Polishing:

Dried turmeric has a poor appearance and rough dull colour outside the surface with scales and root bits. The appearance is improved by smoothening and polishing the outer surface by manual or mechanical rubbing.

Manual polishing consists of rubbing the dried turmeric fingers on a hard surface or trampling them under feet wrapped in gunny bags. The improved method is by using hand operated barrel or drum mounted on a central axis, the sides of which are made of expanded metal mesh. When the drum filled with turmeric is rotated, polishing is effected by abrasion of the surface against the mesh as well as by mutual rubbing against each other as they roll inside the drum. The turmeric is also polished in power-operated drums, The yield of polished turmeric from the raw material varies 12-25 per cent.

Colouring:

The colour of the turmeric always attracts the buyers. In order to impart attractive yellow colour, turmeric suspension in water is added to the polishing drum in the last 10 minutes. When the rhizomes are uniformly coated with suspension, they may be dried in the sun.

Preservation of seed rhizomes:

Rhizomes for seed purpose are generally stored after heaping under shade of tree or in well ventilated shade and covered with turmeric leaves. Some times the heap is plastered with earth mixed cow dung. The seed rhizomes can also be stored in pits with sawdust. The pits can be covered with wooden planks with one or two