Allelopathic effects of Eucalyptus camaldulensis Dehnh. on germination and growth of tomato.

摘要

The study was conducted to determine the allelopathic effect of Eucalyptus camaldulensis on tomato crop. Leaf, root, bark and fruit extracts and soil sample of Eucalyptus camaldulensis were used to run the experiment under laboratory and field condition respectively. The aqueous extracts showed significant (P<0.01) inhibitory effect on germination, root and shoot elongation of tomato plants. The inhibitory effect was proportional to the concentrations of the extracts and the higher concentration (5-10%) had the strongest inhibitory effect. Results also revealed that inhibitory effect was more pronounced in radicle length and germination efficiency rather than plumule length. Soil sample also showed significant(P<0.01) inhibitory effect on shoot length, root length, leaf area index and dry weight. However, there was no significant difference in the survival of the seedlings planted on the different soil samples. From the obtained results, it can be concluded that, eucalyptus seem to be a potential threat to the vegetable industry under small-scale farming condition. The other conclusion is that, tomatoes are incompatible with Eucalypts in agro-forestry systems. Therefore, it could be recommend that different remedial practices (like removal of excess leaf litters, planting after the rains) should be done before planting vegetables, in land previously planted with Eucalyptus in order to reduce the potential risks. Finally, it is important to carry out long-term field based studies to investigate the significance of these results.