Total microbial biomass of the organic wastes was significantly (P < 0.05) increased due to vermicomposting (Fig. 1). Periodical analysis indicated an exponential nature of biomass dynamics in organic substrates during vermicomposting. Addition of PM significantly (P <

0. 05) increased microbial biomass in final vermicompost. The highest MBC content was registered within 15-30 days of vermicomposting. MBC of vermicomposts, prepared from T1 and T2 were statistically at par. Vermicompost of T3, however, recorded significantly (P <

0. 05) higher MBC as compared to other treatments.

Periodical analysis revealed the variable pattern of biomass dynamics for total microbial community, fungi and bacteria during vermicomposting of various IS and PM mixtures. Ergosterol content i. e., fungal biomass (FBC) in all the treatments was sharply increased in the first 30 days and thereafter decreased gradually till the end of the vermicomposting process (Fig. 2). However, the final fungal biomass of vermicompost was significantly (P < 0.05) higher than that of initial organic substrates. Addition of PM with IS, significantly (P < 0.05) increased fungal biomass of final vermicompost. Vermicompost prepared from T3 recorded significantly (P < 0.05) higher FBC as compared to other treatments and FBC values of vermicomposts, prepared from T and T2, were statistically at par.

Periodical analysis results revealed that total FAME content in vermicompost followed almost same of ergosterol content (Fig. 3). The highest FAME was recorded in T3 treatment and it was significantly higher than other treatments.

Muramic acid was estimated as an indicator of bacterial biomass. Periodical estimation of muramic acid in the waste mixture revealed a steady increase in the muramic acid content up to 45 days of the process and thereafter it decreased till the end of the process. The final muramic acid contents of vermicomposts, prepared from T2 and T3, were significantly (P < 0.05) higher than that of their initial waste mixtures. In case of T0 and T1 treatments, muramic acid contents of vermicomposts were statistically at par with that of initial wastes. Analysis revealed that muramic acid contents of vermicomposts, prepared from T0 and T1 treatments, did not differ statistically among them.

3.2 Plant growth promotion

Incubation of radish seeds with ethyl acetate extract of vermicomposts for 5 days significantly (P < 0.05) increased root and shoot length of radish as compared to control. Column chromatography of concentrated ethyl acetate extract of vermicomposts yielded 24 fractions. Radish bioassay with all these fractions revealed that 3 fractions (5th, 7th and 8th) out of 24 fractions were able to increase radish root and shoot length as compared to control as well as other fractions (Fig. 5). The root and shoot length of all fractions were presented in Fig. 6. Vigor index, summation of root length and shoot length, is a good indicator for plant — growth promotion and its highest value was recorded in fraction 5.

HPLC analysis of these three fractions confirmed the presence of indole acetic acid (IAA) in 5th fraction (Fig. 7). Incubation of serially diluted vermicomposts extract in tryptophan- amended broth medium revealed pink colouration after 7 days incubation. Colorimetric analysis indicated the presence of 137 ^g IAA L-1 medium after 7 days.