SOME RECOMMENDATIONS AND FUTURE DIRECTIONS

Keeping in mind the allelopathic interactions of tree species with crops under agroforestry systems, efforts should be made to minimize their negative effects on the associated crops and to manipulate them for practical use. This could be achieved by suitable combinations of allelopathic trees and crops to get the desirable effects. Even the mulch and residues of allelopathic tree species can be managed to reduce weed populations. One of the recent approaches of using allelopathy as a tool for weed management is by exploiting signaling effects of potential allelochemicals in the rhizosphere (Birkett et al., 2001). Desmodium species (Desmodium unicinatum DC. and Desmodium intorum [Mill.] Urb.) intercropped in maize crop suppressed parasitic weed Striga hermonthica and repelled insect pests, particularly stem borers, and it was attributed to the allelopathy of Desmodium spp.

(Khan et al., 2002). However, further research in this direction is required. Efforts should also be made to understand the role of roots in various underground interactions. Roots could also release allelochemicals through exudates, leachation, or decomposition on death and decay. This aspect is highly neglected in the allelopathic studies, and further efforts are required to understand belowground interactions involving roots.

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50 Ecological Basis of Agroforestry

4 Approaches to

Tree–Environment–Crop