Senna

Synonyms

Senna leaf, Sennae folium, Senai-ki-patti, Tinnevelly senna, Cassia senna.

Biological Source: It consists of dried leaflets of Cassia angustifolia or Cassia senna Vahl

Family: Leguminosae.

Geographical Source

Tinnevelly, Madurai and Ramnathpuram districts of Tamil Nadu.

Cultivation, Collection and Preparation

25000 hectares of land is under cultivation of senna in India, producing about 22500 tonnes of leaves and 7500 tonnesof frljit? per annum. Senna is mainly cultivated in Tinnevelly, Ramnathapuram districts and their adjacent areas in Tamil Nadu State and is exported by ships from Tuticorin port. Senna is a small shrub of 1.5 m, having compound paripinnate leaves and each leaf has got g - 5 - 7 pairs of leaflets For the cultivation, generally red loamy or coarse gravelly soil is selected, but it also grows on alluvial loamy soil. Before sowing, the land is ploughed twice, harrowed and levelled. First sowing is done in February-March, while second sowing is carried out in October to November i.e. after rains. Normally, the sowing is done by broadcasting method. For earlier germination, the seed surface is abrased or triturated with sand. About 15-25 kg of seeds are required per hectare of land and seeds are sown thinly. The plants are grown as a semi-irrigated or light-irrigated crop. Heavy irrigation, water logging etc are avoided. Also, the plant cannot survive at very low temperatures.

The plants are allowed to grow for about five months till the growth of flower stalks occurs. Though, it is a leguminous plant, still the application of nitrogenous fertilizers is beneficial because of lack of root nodules.

after 2 - 3 months of sowing, the harvesting of leaves is done in three stages. The first plucking is done when the leaflets are thick, full-grown and greenish in colour. After one month, second plucking is done and last plucking is carried out after 4 - 6 weeks. Normally, the plants are uprooted after third plucking of leaves) It is observed that the content of sennosides in leaves is. maximum when they are fully grown and goes on decreasing along with maturation of pods. Senna crop which is taken after the rice crop on the same land in same season gives best yields and senna grown on dry land without proper irrigation gives poor results. After collection, the leaflets are dried under shade or indoor by spreading them in thin layers. Drying takes place within 7- 10 days and leaves show yellowish-green colour. The leaves are tossed to separate pods. They are then packed into bales under hydraulic pressure. Pressing the leaves under hydro lye press produces. Transverse line on this leaves. Which are absent in alexendrian senna-leaves.

During storage, the drug should be protected from light. .But, generally if does not lose the potency atleast upto 5 years. About 1,200 kg of leaves and pods are obtained in one hectare of irrigated land and 700 kg of drug from rainfed land.