Variety Issues in Stevia

[seetharam annadana]

Dear Stevia Enthusiasts, I thought of sending this message around, after receiving several personal phone calls across the country on the issu of varities of Stevia.

Stevia is self incompatible, hence it can only produce seeds when it is crossed with a different species. Such seeds have low germination percentage (6%) and the seedlings will be seggregating. To get such material it takes 3 years. If these seggregating material has to be identified for its potential across the country, we need at last 3 more years. Lastly if this has to be commercilised we need 3 more years to have enough plants developed by TC or vegetative methods.

Varities doing rounds in the market...is it genuine? This is not easy to comment, as i have not see these so called varities, and i also have no agronomic data on their performace in southern/central/western/eastern and northern zones. Based on the time it takes to develop varities, i am sure no work has been done in India.

It is very likely that some plants have been imported from USA, China, Paraguay, Peru, Coloumbia at best, mutplied and are being sold as varities.

With the most widely used material in Southern India, the material with which we started in 1997, We can obtain a yield of easily upto 6-6.5 tons of dried leaf per acre per year, with a density of 50000 plants per acre. For most of the months the stevioside content in the leaf, harvested at the correct time of the day shows between 11.8-12%. 80:20 ratio of Ste-RebA. Agronomically and biochemistry wise this is OK.

If there are indeed plant material with higher yields, or stevioside content or improved Ste-RebA rations, provided we can ascertain them with tests, it may be not be logical to accept materials as a new varieties.

Regards