STEVIA

Stevia is also known as ‘honey plant’ because it is sweeter in taste. It is a natural sweetener which is given mainly to diabetic patient to balance insulin in their body. Its leaves are used for preparing various drugs. Drugs prepared from Stevia are used for treatment of diabetes, reduces tooth cavity, tonics, reduces calories from food etc. It is a perennial herb with average height of 60-70cm. Leaves are oppositely arranged and are green in color and flowers are small and white in color.

It is available in three form i.e. Fresh leaves, dried leaves, stevia extract and liquid concentration. Liquid concentration is black syrup and used in flavouring of various dishes.
 
Punjab, Chhattisgarh, Karnataka, Maharashtra, Madhya Pradesh and Andhra Pradesh are major Stevia growing states in India.
 

It is grown in wide variety of soils. It gives best result when sown in sandy loam to loamy soil with good drainage system and high organic content. Avoid cultivation in saline soils as it is harmful for the Stevia. The pH ranging from 6-8 is best for plant growth.

SRB 128: The variety is suitable for growing in both North and south areas. The leaves contain 21% of glucoside content.

SRB 123: Its harvesting is done 4-5 times. The leaves contain 9-12% of glucoside content.

SRB 512: Suitable for sowing in north area. Its harvesting is done 4 times. The leaves contain 9-12% of glucoside content.

R 42: The leaves are large and thick which contains 5-10% stevioside, 4% rebaudioside and 0.5-1% dulcoside P.

Other state varieties:

MDS-13 and MDS-14: Grows well in Indian climatic conditions. It requires high temperature and low or drought rainy season.
 

For Stevia plantation, it requires well prepared field. To bring the soil to fine tilth, plough land 2-3 times. At the time of ploughing mix trichoderma well with soil and at last ploughing FYM is mixed well with soil. Transplantation of Stevia is done on raised beds.

Time of sowing
Optimum time for sowing is from May-June Month.

Spacing
Use plant to plant spacing of 30cm.

Method of Sowing
Stem cuttings are transplanted in field.
 

Seed Rate
When seedlings are transplanted at a distance of 60x30cm in main fields use plant density of 20,000 to 25, 000 per acre.

Seed treatment
For early root initiation, stem cuttings are treated with Paclobutrazol @ 100ppm.

Propagation of stevia is done through stem cuttings or by tissue culture. Select stem cutting of 15cm length from leaf axil of current year plant. February to March is optimum time for stevia propagation. Stem cuttings are ready for transplantation 25 to 30days after rooting.
 

Fertilizer Requirement (kg/acre)

Nutrient Requirement (kg/acre)

At the time of land preparation, apply FYM@104-125qtl/acre, cow dung/urine and vermin compost and mix well with soil. Apply fertilizer dose of N:P:K @18:3:12kg/acre in the form of Urea@40kg, DAP@20kg and Potash@20kg/acre. Apply full dose of DAP as basal dose.

In dry season, irrigation is given at the interval of 15 days. After transplanting, immediate irrigation is required. In winter season, irrigation is required at the interval of 20 days.

In initial 2-3 months weeding is required. After transplanting, weeding should be done at the interval of 25-30 days.

• Pest and their control:
  

Aphids: These are nearly transparent, soft-bodied sucking insects. When present in sufficient numbers, aphids can cause yellowing and premature death of leaves.

For management of Aphid, use chrysoperla predators. 4-6 thousand/acre or use 50 gm/ltr neem concentrate.

• Disease and their control:
  

Septoria steviae: The symptoms are angular grey spot appear on leaves followed by chlorosis.

Sclerotinia sclerotiorum: The symptoms are brown spots appear on the stem of the plant and then withering of whole plant and then it eventually collapses.

Southern blight: it is caused by soil borne fungus Sclerotium rolfsii.
Soil solarization is an effective way to kill Southern blight.

Plant starts yielding in about 3 months after planting. Subsequent harvesting is done at the intervals of 90 days. It should be kept in mind that while harvesting 5-8cm of stem from ground level should left as such for regeneration. Four harvests is mainly done in one year. For processing, leaves are used.
 

After harvesting, drying of leaves is done. The leaves are air dried and then extraction is done. Then the leaves are packed in air tight polybags for transportation purpose and to increase its self-life. From extract leaves various products such as powder, tonics and sugar free tablets are made after processing.