In India, Herbal formulations are preferred due to lesser side effects and low cost. Medicinal plant wealth faces pressure due to shrinking habitats and overuse. Ttherefore in order to cultivate medicinal plants on a large scale new symbiotic fungus Piriformospora indica has been exploited. The neglected but pharmacologically very important crop Trigonella foenum graecum (Fenugreek) has been investigated to find the influence of P. indica on its growth. An investigation to find increase in the secondary metabolites like diosgenin content, bioactivity of glycosides isolated from the leaves of Fenugreek has been done. A novel approach has also been carried out by making a comparison of glycosides isolated from control and P. indica treated plants to find for any change in functional moeity or mass of the compounds. Therefore the book embodies the work based on investigating the interaction between Fenugreek and mycorrhizal fungus and its further phytochemical analysis.