Greenhouse experiment with soil shows that eucalyptus does not interfere allelopathically on grasses, maize and soybean aiming an integrated crop-livestock-forest system

Integrated, livestock, and forest systems represent sustainable agricultural models. A critical aspect of these systems is the strategic combination of plant species that do not inhibit one another's growth through allelopathy. This study assessed the effects of leaf extracts from various eucalyptus ( Corymbia henryi , Eucalyptus camaldulensis , E. dunnii , E. exserta , E. globulus , E. grandis , E. pellita , E. resinifera , E. saligna , and E. urophylla ) on the seed germination and growth of Urochloa brizantha cv. Marandú, Urochloa ruziziensis , Panicum maximum cv. Mombasa, Zea mays , and Glycine max . These species are commonly used in integrated crop-livestock-forest systems. The impact of eucalyptus leaf extracts on the target species was initially evaluated in the laboratory by measuring primary root protrusion and total seedling length. A subsequent greenhouse experiment assessed the influence of these extracts on the growth of the target species through biometric and biochemical analyses. Results showed that eucalyptus extracts had a more significant effect on seed germination (when applied to germination paper) than when incorporated into the soil. Moreover, the extracts exhibited minimal interference with the growth of the target species, suggesting their compatibility for use in integrated agricultural systems. Notably, E. globulus extract enhanced soil enzyme activity, indicating increased microbial activity.