Allelopathic effects of apricot (Prunus armeniaca L.) root on some crops and weeds

Allelopathic effect of apricot (Prunus armeniaca L.) root on some crops and weeds was investigated in two independent experiments. First, the effect of concentrations aqueous extract of apricot root (AAR) was assayed on the seed germination of Cicer arietinum L., Phaseolus vulgaris L., Triticum aestivum L., Zea mays L., Amaranthus retroflexus L., Secale cereal L., and Avena ludoviciana Durieu. In the second experiment, two pot trials were carried out to investigate the effect of AAR and apricot root powder (ARP) on the seedlings of P. vulgaris, Z. mays, S. cereal, and A. retroflexus. The results showed that germination was halted in T. aestivum, C. arietinum, A. ludoviciana, and S. cereal under all treatment levels, in A. retroflexus under 75 and 100%, and in P. vulgaris under 100% of AAR. Also, the results showed that effects of AAR and ARP on the biomass, membrane stability index, chlorophylls, carotenoids, proline, and protein content, and antioxidant enzymes activity were not significant, with a few exceptions. It can be concluded that the allelopathic effect of apricot root is mostly exerted by inhibiting the germination of target plants rather than effect on later stage of plant growth and development.