Rooting and vitality of poinsettia cuttings was increased by arbuscular mycorrhiza in the donor plants.
In this paper, we provide evidence that the rooting performance of cuttings can be improved by the arbuscular mycorrhizal (AM) symbiosis of donor plants. Poinsettia stock plants were inoculated with the Glomus intraradices isolate H510 and grown in three different cultivation systems (two organic, one conventional). AM colonization was not related to P availability in the substrate. Decay of the excised cuttings in response to unfavourable post-harvest storage conditions was significantly reduced by AM colonization of the stock plants. In most cases, AM significantly promoted the formation of adventitious roots in the stored cuttings. The strongest effect of AM was found when donor plants were grown in a modified organic substrate; then AM-conditioned cuttings showed higher leaf sugar levels and a changed kinetic of carbohydrates during storage. Analyses of N, P, and K in cuttings did not indicate a nutritional effect. The results support the idea that an altered carbohydrate metabolism but also plant hormones can contribute to improved rooting performance of cuttings excised from mycorrhizal donor plants.
Druege, U.; Xylaender, M.; Zerche, S.; von Alten, H. 2006. Rooting and vitality of poinsettia cuttings was increased by arbuscular mycorrhiza in the donor plants. Mycorrhiza, 17 (1), 67-72.