“A full guide to the scientific approach of cultivation of stevia rebaudiana “
In India, where the farmers are being disillusioned with the traditional farming in the present time, they have left the domestic farming and started thinking about commercial farming but due to lack of accurate information, it is breaking their morale. Keeping this in mind farmer can earn by the cultivation of “stevia” One acre of stevia equals ten acres of sugarcane.
Stevia rebaudiana (Bert.) Bertoni is one of the 154 members of the genus Stevia of the sunflower family. It is a small seasonal plant which grows to a height of 1–2 feet. It has elongated leaves that grow along the stems and are lined up against each other It is popularly known as the sweet herb of Paraguay /Candy leaf/ Sweet Herb. Farmers can earn good profits by cultivating it, stevia is the most useful and economical plant for the progressive farmers of India, Stevia most commonly found on the banks of rivers, ponds it has been reached to Japan also due to its sweetness. , Slowly spreading from there, it has developed commercially in Korea, Taiwan and other South Asian regions. Now it has been cultivated in India.
It is a small seasonal plant which grows to a height of 1–2 feet. It has elongated leaves that grow along the stems and are lined up against each other its leaf just looks like basil in appearance and it will not be an exaggeration that it is a “sanjeevani booti ” for the people suffering from diabetes, hypertension and obesity. The usefulness of stevia is due to the sweetness and medicinal properties found in it and due to these properties, its economy is also very important in term of its commercial value. Stevia plant leaves have more than 30% sweetness in comparison to common sugar and it is 300 times sweeter than normal sugar. Being a herbal product, stevia is a completely safe herb. Stechia’s role in controlling blood pressure and blood sugar.
Medicinal Value of Stevia Plant ;
- Stevia is consumed as a non-nutritive sweetener and herbal supplement.
- A non-nutritive sweetener is one that contains little to no calories.
- It is consumed as a healthful alternative to added sugar in a lot of meals and beverages.
- Stevia contains eight glycosides. These are the sweet components which are isolated and purified from the leaves of stevia plants.
- stevia showed minimal to no effects on blood glucose, insulin levels, blood pressure, and body weight. Hence it is helpful in controlling diabetes.
- It posses no sugar and very few if any, calories. Stevia can be part of our well-balanced diet to help us to reduce energy intake without any sacrificing taste. So, we can say it controls obesity.
- Many studies revealed that kaempferol can reduce the risk of pancreatic cancer by 23 percent.
- Glycosides present in the extract of stevia have been found very useful to dilate blood vessels. Glycosides can also increase sodium excretion and urine output.
- Steviol glycosides present in the stevia are non-reactive and are not metabolized to reactive compounds, therefore, it is unlikely that the steviol glycosides under evaluation should cause by themselves allergic reactions when consumed in foods.”
Required Soil and Climatic Condition for Stevia Cultivation ;
Stevia is a subtropical crop which requires a warm climate with a minimum frost prevailing conditions. Stevia can be grown in the area where the annual average temperature lies between 30 to 35-degree Celsius with an average annual rainfall of 14o cms. The day temperature should not be exceeded over 48-degree Celsius and night temperature should not befall below 4 degrees celsius.
Stevia grows very well in sandy loam soil having a pH range of 6.75 to 7.5 ( Acidic to Neutral soils ).
Propagation of Stevia Plant ;
Stevia is propagated through the stem cuttings of approximately 15 to 20 cms.in length which should be taken from the leaf axil of the current year plant.
Time of propagation; it can be planted in the month of July or in February- March. ( irrigated conditions ) 25 to 30 days old cutting after rooting is ready to transplant in the main field.
Planting of Stevia ;
Planting should be done with a plant to plant distance of 45 cms. apart and there should be 30,000 plant density must be maintained in a field of one hectare.
Manuring in Stevia ;
The recommended dose of NPK fertilizer is 35: 115;115 kg / Ha.
Method of making the field suitable for Stevia Farming ;
For build up the organic matter within the soil, which successively helps in the sustained nitrogen nutrition of the crop also as improved availability of other nutrients, a pre-plantation manure crop is extremely helpful. Leguminous plants like Sesbania aculeata, Sesbania rostrata, Crotolaria juncea, Clover, Vetch, Soybean, Alfalfa or Cow-pea are good choices as manure crop. The crop is grown on the farmland, either with irrigation or in season. The plants are allowed to grow for 3 to 4 weeks then they’re incorporated into the soil by tilling. Then they’re allowed to decompose within the soil for an adequate period before transplantation of Stevia.
Weed control ;
Avoid the use of medicine for weeding, broad-leaved weeds etc. Hand weeding should be regularly incorporated in every 45 – 55 days of a gap. it helps in airflow in and around the field which is beneficial for the vegetative growth of the stevia plants.
Harvesting can be done when plants attain a height of 45 -60 cms. The shorter days induce the flowering in stevia for getting optimum biomass ( yields ) the harvesting must be done before blooming the flowers.
The estimated dry green leaves yield is about 3.5 to 5 tonnes / Ha after 4 to 6 cutting per year. Harvesting can be done up to 5 years of the stevia planting.
Post Harvesting ;
Always dry dried leaves in partial sunlight.it generally takes 36 to 48 hours at the temperature range between 45 to 50-degree celsius. Immediate after the drying of leaves separates the leaves from the stem by using specialized thrasher.