Assessment of the Effects of Neem (Azadirachta indica) Extract on Reproductive Performance of the Earthworm, Eisenia foetida.

The present study demonstrated that Neem extract produced a comparatively mild inhibitory effect on the reproductive performance of Eisenia foetida. Juvenile emergence remained relatively high across all concentrations tested, although a general decline was observed with increasing concentration. Mean juvenile production decreased from 59.00 ± 1.00 in the control group to 54.00 ± 1.00 at 600 mg/kg, while reproductive inhibition increased from 1.69% at 100 mg/kg to 8.47% at 600 mg/kg. The statistically significant ANOVA result (p = 0.029) indicates that Neem extract concentration significantly influenced juvenile emergence. Furthermore, the strong negative correlation between Neem concentration and juvenile production indicates that increasing exposure was generally associated with reduced reproductive output. However, the magnitude of inhibition remained relatively low, and the slight variation observed at 500 mg/kg indicates that the response was not strictly concentration-dependent at every exposure level. Overall, the results indicate that Neem extract did not cause severe reproductive impairment in E. foetida under the conditions of the present experiment. Even at the highest concentration tested, reproductive inhibition was limited to 8.47%, suggesting that the reproductive capacity of the earthworms was largely maintained. Therefore, Neem extract appears to have relatively low reproductive toxicity toward E. foetida within the tested concentration range and may represent a comparatively earthworm-compatible botanical pesticide. Nevertheless, further long-term studies examining cocoon viability, hatching success, juvenile growth, repeated exposure, and field-level application conditions are recommended to establish its ecological safety more comprehensively.

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