Changes in Cutting Composition during Early Stages of Adventitious Rooting of Miniature Rose Altered by Inoculation with Arbuscular Mycorrhizal Fungi

Abstract

<jats:p>Many changes in metabolism are known to occur during adventitious root formation, including changes in amino acids, proteins, and carbohydrates. The influence of arbuscular mycorrhizal fungi (AMF) on adventitious rooting of rose was tested by inoculating four cultivars with <jats:italic>Glomus intraradices</jats:italic> Schenck &amp; Smith. Changes in cutting composition were measured during the initial stages of adventitious root formation. Although there were cultivar-specific differences in response, AMF inoculation generally increased the biomass and number of adventitious roots on cuttings before root colonization was detected. Application of rooting hormone increased this effect. Inoculation with AMF washings also increased the root biomass and number, but only when cuttings were treated with hormone. Changes in cutting composition in response to AMF were detected at 7 to 14 days. Differences in protein concentrations in response to AMF or hormone application were similar, while differences in amino acid and reducing sugar concentrations were not. Concentrations of proteins and amino acids in cuttings at the beginning of the experiment were positively correlated with adventitious rooting, while concentrations of reducing sugars and nonreducing sugars were not correlated with rooting. These results suggests that nitrogen-containing compounds play an important role in adventitious rooting, and that changes in amino acids associated with AMF inoculation were potentially different than those that occurred when cuttings were treated with rooting hormone alone. Carbohydrate concentrations in cuttings were not strongly related to initiation of adventitious roots, but reducing sugar may play a role in regulating part of the response of cuttings to AMF. The response of rose cuttings prior to colonization by <jats:italic>G. intraradices</jats:italic> suggests that AMF-plant signaling events occurred prior to rooting.</jats:p>

Adventitious rooting in apple rootstock MM.106: Effects of arbuscular mycorrhizal fungi (AMF) and plant growth regulators

“…These results agree with those obtained by Scagel et al (2004), Piedra et al (2005), Zai et al (2007), Druege et al (2007), and Santelices and Palfner (2010) in rose, olive, beach plum, poinsettia, and hazelnut cuttings, respectively. Compared with untreated control cuttings, the effects of G. fasciculatum were best for most of the parameters measured, while S. dussi plus CA frequently gave values close to those in the untreated controls.…”

“…However, in order to realise the maximum benefit from AMF inoculation, it is necessary that colonisation occurs during the early stages of plant growth (Krishna et al, 2010). Therefore, to obtain these benefits in horticultural production systems, the AMF inoculum should be present during emergence of the radicle or during adventitious root formation in cutting propagation (Scagel, 2004). This study showed the beneficial effects of inoculation with each of three AMF, which resulted in enhanced rooting and improved growth of apple rootstock (MM.106) cuttings.…”

“…There is evidence that plant growth regulators (PGRs) are directly related to plant-AMF interactions. Genotype-specific responses to adding an AMF inoculum to the rooting medium suggests that combinations of AMF and PGR applications should be evaluated before an AMF inoculum is used for the mass propagation of a specific genotype (Scagel, 2004). Therefore, understanding the interaction between PGRs and AMF could be beneficial, especially for improved plant quality (Dutra et al, 1996).…”

Effects of arbuscular mycorrhizal fungi on the rooting and growth of beach plum (Prunus maritima) cuttings

“…Many studies support the idea that AM fungi can modify root morphology through their effects on phytohormone levels (Scagel, 2004;Niemi et al, 2002). Kaldorf and Ludwig-Müller (2000) inoculated maize plants with G. intraradices, and showed that the levels of both free and bound indole-3-butyric acid (IBA) were increased at different stages of colonisation, accompanied by increased percentages of fine lateral roots.…”

Evaluating a Novel Method to Introduce a Mycorrhizal-like Fungus, Piriformospora indica, via an Inoculated Rooting Substrate to Improve Adventitious Root Formation

“…Mutualistic fungi, such as AM fungi and P. indica, added to propagation media have been shown to increase root weight and root initiation in a range of plant species, including dwarf umbrella tree (Schefflera arboricola), anglojap yew (Taxus ·media), rose (Rosa 'Scarlet Cupido'), bearberry (Arctostaphylos uva-ursi), geranium (Pelargonium sp. ), malabar nut (Adhatoda vasica), and poinsettia (Druege et al, 2007;Fatemeh and Zaynab, 2014;Rai and Varma, 2005;Scagel, 2004aScagel, , 2004bScagel et al, 2003). These studies suggest that P. indica may be an alternative to chemical auxin application while also imparting additional benefits such as disease suppression or nutrient uptake.…”