The Role of Earthworms in Tropics with Emphasis on Indian Ecosystems

The paper highlights the research carried out by different scientists in India on aspects of earthworm population dynamics and species diversity, associated with other soil fauna and microflora. It also deals with the importance of earthworm activity on physicochemical properties of soil with reference to India and other tropical countries. Stress is laid on the earthworm plant association and importance of the secretions of earthworms as plant growth stimulators. Moreover, the earthworm species reported and being utilized for vermicomposting in India are discussed, since vermicomposting is the ultimate technology which renders for the improvement of soil fertility status and plant growth. Earthworms serve as indicators of soil status such as the level of contamination of pollutants: agrochemicals, heavy metals, toxic substances, and industrial effluents; human-induced activities: land-management practices and forest degradation. In all these fields there is lacuna with respect to contributions from India when compared to the available information from other tropical countries. There is lot of scope in the field of research on earthworms to unravel the importance of these major soil macrofauna from holistic ecological studies to the molecular level

Neurohumoral induction and enzyme compensatory changes to cold acclimation in earthworms

Aldolase, lactate dehydrogenase, and succinate dehydrogenase activities were measured in body wall muscle of Lampito mauritii and Perionyx excavatus acclimated to 17° and 10°, resp. Aldolase activity significantly increased and succinate dehydrogenase activity decreased in earthworm muscle during cold acclimation. The relative activities of 4 lactate dehydrogenase isoenzymes significantly changed in cold acclimation. Similar results were found in worms kept at control temps. after a coelomic injection of nerve cord exts. from cold-​acclimated worms. Apparently, neurohumoral factors which regulate metabolic pathways are synthesized by earthworms during cold acclimation

Development of callus and cell suspension culture from the leaf of Adhatoda vasica Nees using economical growth media

195-200Adhatoda vasica Nees, commonly called Vasaka or Arusha has high medicinal value owing to its rich flavonoid and alkaloid contents. The alkaloid content of A. vasica is known to vary with genotype, and hence vegetative method is recommended for its propagation. Effective medium for A. vasica propagation is an area of interest to researchers. Suspension culture techniques have demonstrated that alkaloids can be recovered from the callus and the suspension cell cultures. In this context, we tried to emphasis upon the use of economically viable organic vermicompost and its extracts along with coelomic fluid as plant tissue culture medium without involving expensive chemicals. In the present study, an organic experimental economical medium being standardized using vermicompost, its extracts along with coelomic fluid and friable soft callus was obtained from leaf explants of A. vasica Nees without any chemical supplementation. Direct shoot formation with leaves was documented on MS medium supplemented with 2 mg/L BAP and 3mg/L IBA. Cell suspension medium is standardized using vermicompost extract and the coelomic fluid (3:1 ratio). Suspension cell culture showed cell separation and multiplication of callus. Presence of total phenolics in callus and in vivo plants exhibited no significant variation. Flavonoid content was significantly higher in the callus and suspension cell extracts, Statistically Student’s t-test comparative analysis have shown significance at one per cent level where P ≤0.05 for phenols and flavonoids. Alkaloids were detected on TLC plate, under UV light at 245 and 365 nm, respectively. Rf values of vasicine was found to be 0.4 which corresponds to that of standard vasicine and 0.60 for vasicinone, respectively. HPLC confirmed the presence of vasicine at 5.461 min. This study enables analysis of callus and suspension cell culture for the presence of various secondary metabolites