B. Niroula / Our Nature (2003) 1: 10-14
However, other ef luents/ sewage had no signi icant effect on rice seedling.
Ef luent of Himalaya Soap and Chemicals had lethal toxic effect on both the test crops. On germination rice remained more sensitive and susceptible to the toxic effect of industrial ef luents while blackgram proved to be more tolerant. Leather Industry ef luent had signi icant inhibitory effect on germination and seedling growth of rice but it remained negligible on blackgram for both the parameters. For blackgram seedling, Diesel Power House and Shah Udyog ef luents had signi icant inhibitory effect while they had little or no impact on germination and seedling growths on rice.
Plants show different degree of responses with effluents at different stages of development and also the magnitude of
1995, Niroula 1996, Shrestha 2000).
Ghimire and Bajracharya (1996) reported significant differences in the sensitivity of four types of vegetable seeds (Brassica juncea, B. oleracea, B.rapa and Raphanus sativus) of a single family Brassicaceae) to the effluent of carpet dyeing, tannery and steel industries.
Gupta and Chapagain (1999) observed significantly different effect of polluted water of Dhobikhola on Pisum sativum and
seedling growth of all tested vegetables were highly sensitive to the effluents but the nature
of the sensitivity varied effluents and seed types.
various sewage increase
industrial effluents and municipal on germination and dry weight on rice and blackgram. In this study
sensitively to the tested effluents / germination and seedling growth.
Reduction in germination and seedling growth in the test crops by the industrial effluents in the present study may be due to osmotic inhibition of water absorption and / or heavy metal toxicity inhibiting the functions of essential enzymes (Jerome and Ferguson 1972, Mayer and Poijakoff Mayber 1982). To understand the exact nature and causes of different industrial effluents / sewage on the tested plants it still awaits detail physico-chemical analysis and further research in different growth parameters.
Acknowledgements Author is grateful to Department of Botany, Post Graduate Campus Biratnagar, and T.U. for providing laboratory facilities.
Diesel power House
Hetaunda Iron & Steel
Himalaya Soap &
Table 1. General features of the industrial effluents, Sub metropolitan sewage and tap water
6 7 8 7
Dissolved oxygen (mg/l)
Dissolved solutes (g/l)