Spurges Euphorbia spp

One of the features of allelopathy, as pointed out by Rice (18). is that it is specific. Certain species, but not others, are affected by the allelochemics produced by a plant. This suggests that allelopathy by a weed must be positively demonstrated for each crop. References to specific reports of demonstrated allelopathy by a weed on a crop are given in Table 1. In some cases [crabgrass (Digitaria sanguinalis (L.) Scop.), spurge (Euphorbia spp.), etc.], no crop is listed in the allelopathy column. 

You can also prepare your own plant extract, as in the reference below. Use a plant species that herbivores avoid snch as spurges Euphorbia spp.) or false hellebore Veratrum viride). Separate plant parts such as leaves, stems, and roots. Grind plant parts separately with ethyl acetate in a blender. (In onr work, we extracted 60 g of roots of Euphorbia lathyris with 2(X)-ml ethyl acetate. For about 300 g plant tops we used 400-nil ethyl acetate.) Filter the extract, discard the plant tissue. 

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