Allelopathic Effects of Nech Bahirzaf (<i>Eucalyptus globulus</i> Labill.) on Germination and Seedling Growth of Crops

Objectives The objective of this study was to test the alleopathic effects of E. globulus leaves and litter fall aqueous extracts on germination and growth of Winter Wheat (Triticale hexaploide), Barley ( Hordeum vulgare), and Maize ( Zea mays) crops. Methods Allelopathic potential of Eucalyptus globulus on germination and seedling growth of Maize ( Zea mays), Winter Wheat ( Triticale hexaploide), and Barley ( Hordeum vulgare) was studied under laboratory conditions. Aqueous extracts of young tree leaves, old tree leaves, and litter fall of E. globulus were prepared. Filtered extracts were used to treat germinating seeds of test crops. Open and undercanopy soils collected from different depths were also tested for allelopathic effects. ANOVA was used to analyze data in SAS software. Means were compared using Tukey's HSD test at the 5% level of significance. Results The result indicated that the extracts of E. globulus had a significant inhibitory effect on germination and seedling growth of the test crops. The highest effect of extracts was observed from old tree leaves, followed by young tree leaves, and the least from litter fall. Among the three crops, Z. mays found to be more sensitive than others. However, the undercanopy soils did not show any allelopathic effect on test crops. Conclusion We concluded that E. globulus allelochemicals do not accumulate in soils and the crops can develop adaptation through time. Thus, use of E. globulus for agro-forestry with removal of fallen leaves before cultivation is recommended.