Arbuscular mycorrhizal fungi species associated with rhizosphere of Phoenix dactylifera L. in Morocco

A survey of arbuscular mycorrhizal fungi (AMF) diversity and date palm (Phoenix dactylifera L.) tree root colonization in arid areas was undertaken in ten palm groves located along the Ziz valley (Tafilalet, south-west Morocco). The frequency and the mean intensity of root colonization reached 72 and 43% respectively and the spore population varied from 238 to 1840 spores/10g of soil. The AMF colonization levels of field date palm roots were found to be negatively correlated with soil phosphorus content (r2 =-0,64). A total of ten AMF species were trapped from the 10 studied sites with a population of 4 to 7 species per sites. The isolated species included: Glomus mosseae, G. fasciculatum, G. constrictum, G. aggregatum, G. macrocarpum, 3 undescribed species of Acaulospora and two of Scutellospora genera. The latter two species were trapped only at the second trapping cycle.Keywords: AMF, diversity, Morocco, palm grove, Phoenix dactylifer,

Mycorrhizal fungi as natural bio-fertilizers: How to produce and use

This technical handbook provides an easy to follow guide describing the process on how to produce home-made mycorrhizal inoculants using different types of propagation units and how inoculants can be applied as bio-fertilizers in the nursery and during field transplantation for improving the growth and stress tolerance of crop plants

Unique arbuscular mycorrhizal fungal communities uncovered in date palm plantations and surrounding desert habitats of Southern Arabia

The main objective of this study was to shed light on the previously unknown arbuscular mycorrhizal fungal (AMF) communities in Southern Arabia. We explored AMF communities in two date palm (Phoenix dactylifera) plantations and the natural vegetation of their surrounding arid habitats. The plantations were managed traditionally in an oasis and according to conventional guidelines at an experimental station. Based on spore morphotyping, the AMF communities under the date palms appeared to be quite diverse at both plantations and more similar to each other than to the communities under the ruderal plant, Polygala erioptera, growing at the experimental station on the dry strip between the palm trees, and to the communities uncovered under the native vegetation (Zygophyllum hamiense, Salvadora persica, Prosopis cineraria, inter-plant area) of adjacent undisturbed arid habitat. AMF spore abundance and species richness were higher under date palms than under the ruderal and native plants. Sampling in a remote sand dune area under Heliotropium kotschyi yielded only two AMF morphospecies and only after trap culturing. Overall, 25 AMF morphospecies were detected encompassing all study habitats. Eighteen belonged to the genus Glomus including four undescribed species. Glomus sinuosum, a species typically found in undisturbed habitats, was the most frequently occurring morphospecies under the date palms. Using molecular tools, it was also found as a phylogenetic taxon associated with date palm roots. These roots were associated with nine phylogenetic taxa, among them eight from Glomus group A, but the majority could not be assigned to known morphospecies or to environmental sequences in public databases. Some phylogenetic taxa seemed to be site specific. Despite the use of group-specific primers and efficient trapping systems with a bait plant consortium, surprisingly, two of the globally most frequently found species, Glomus intraradices and Glomus mosseae, were not detected neither as phylogenetic taxa in the date palm roots nor as spores under the date palms, the intermediate ruderal plant, or the surrounding natural vegetation. The results highlight the uniqueness of AMF communities inhabiting these diverse habitats exposed to the harsh climatic conditions of Southern Arabia

Full Length Research Paper - Arbuscular mycorrhizal fungi species associated with rhizosphere of Phoenix dactylifera L. in Morocco

A survey of arbuscular mycorrhizal fungi (AMF) diversity and date palm (Phoenix dactylifera L.) tree root colonization in arid areas was undertaken in ten palm groves located along the Ziz valley (Tafilalet, south-west Morocco). The frequency and the mean intensity of root colonization reached 72 and 43% respectively and the spore population varied from 238 to 1840 spores/10g of soil. The AMF colonization levels of field date palm roots were found to be negatively correlated with soil phosphorus content (r2 = -0,64). A total of ten AMF species were trapped from the 10 studied sites with a population of 4 to 7 species per sites. The isolated species included: Glomus mosseae, G. fasciculatum, G. constrictum, G. aggregatum, G. macrocarpum, 3 undescribed species of Acaulospora and two of Scutellospora genera . The latter two species were trapped only at the second trapping cycle

In vitro colonization of date palm plants by Rhizophagus irregularis during the rooting stage

The use of in vitro culture of date palm plants Phoenix dactylifera, associated with arbuscular mycorrhizal (AM) fungi is a novel approach for the production of bio-fortified plants that are free of pathogens. Here, we report, for the first time, the in vitro mycorrhization of in vitro date palm plants using the AM fungus Rhizophagus irregularis MUCL 41833. Date Plants were used in an in vitro cultured system that consisted of a root compartment (RC) containing germinated seeds of Barrel Clover, Medicago truncatula, and spores of Rhizophagus irregularis as a mycorrhizal donor, and a hyphal compartment (HC) with a barrier separating the RC from the HC. In vitro cultured date palm plants, at the two-leaf stage, were placed in the HC section of the culture plate that after 6 weeks contained an active growing extraradical mycelium network of the fungus. Roots of the date palm became colonized after 10 weeks and hyphae, vesicles, spores and arbuscules, were detected. No differences were noticed in above-ground parameters between mycorrhized and non-mycorrhized plants, in which there was no fungus in the HC. However, the total root length was significantly higher and secondary and tertiary roots were significantly more numerous, in the mycorrhized plants. It is hypothesized that these differences are related to stimulating molecules released by the profuse extraradical mycelium of the fungus growing in close contact with the palm root system. Root colonization percentages were of the same order as those reported in pots cultures of the date palm plants. This work opens the door for the large-scale in vitro mycorrhization of date palm plants, potentially better adapted to acclimatization phase and possibly to the field