Evaluation of changes in quantities and types of substrates containing organic wastes on the growth and reproduction of the earthworm 'Eisenia fetida'

The feasibility of converting organic wastes into vermicompost and the effect of adding such wastes onto the substrate on the growth and reproduction of the earthworm 'Eisenia fetida' were investigated in the present study through a factorial experiment with completely randomized design in triplicate, consisting of two factors.

The first factor with nine different treatment combinations included control, potato (P), carrot pulp (C), vegetables (V), sawdust (S), potato, vegetables, carrot pulp (PVC), sawdust, potato, carrot pulp (SPC), vegetables, sawdust, potato (VSP), and carrot pulp, vegetables, potato, sawdust (CVPS), and the second factor was related to two different substrate concentrations of 100 and 150 g. This research was carried out using a basket method in Tonekabon County in 2021. The base substrate of earthworms was animal manure positioned in boxes and washed with urban tap water to reach a pH value of 6.5-7. After ripening the vermicompost, the boxes were emptied and the number of worms was counted individually.

The results of analysis of variance showed a significant difference in the number of cocoon between the studied treatments (P<0.1), but no in the number of worms between the groups. The maximum number of cocoon (mean= 605) corresponded to the sawdust treatment combination (S) and the minimum number of cocoon (mean= 185) was found in the vegetable treatment combination (V).

Overall, the results of this study demonstrated that the treatment of manure bed with sawdust wastes provided the optimal conditions for the growth and reproduction of earthworm 'Eisenia fetida.