First record of in vitro formation of ectomycorrhizae in Psidium cattleianum Sabine, a native Myrtaceae of the Brazilian Atlantic Forest

Abstract

Like many other species of trees native to the Brazilian Mata Atlântica (Atlantic Forest), the Myrtaceae, such as the Red Araza (Psidium cattleianum Sabine), are widely cited as arbuscular mycorrhizal formers. Nevertheless, recent studies show evidence that Myrtaceae from different tropical, subtropical and neotropical ecosystems can also prompt the formation of ectomycorrhizae, indicating that this species' ectomycorrhizal status should be further explored. Because of this, this research effort studied the in vitro interaction between the Red Araza and two ectomycorrhizal fungi isolates, belonging to the Pisolithus microcarpus (D17) and Scleroderma citrinum (UFSC-Sc133) species. An analysis was performed to determine the formation of ectomycorrhizal structures, or lack thereof, and the developmental differences between the in vitro mycorrhized and non-mycorrhized plants. The analysis proved that indeed an ectomycorrhizal association was developed between the Red Araza, and the D17 and UFSC-Sc133 isolates, a fact never before registered in the existing literature. After an in vitro period of 110 days, it was confirmed that the D17 and UFSC-Sc133 isolates formed mycorrhizal colonization of 91.6% and 15.7%, respectively. Furthermore, both isolates also promoted root thickening, and the formation of a fungal mantle and a Hartig net. However, when compared to the Control plants, the fungal isolates did not contribute to an increase in the development of the subject plants, possibly due to the specific experimental conditions used, such as a high humidity environment and high availability of nutrients in the symbiotic substrate.

Misdiagnosis of mycorrhizas and inappropriate recycling of data can lead to false conclusions

“…A recent study found that altogether 17% of the tested saprophytic fungi colonized the surface of roots, but only one formed a Hartig net‐like structure (Smith et al ., ). Another recent study found that Psidium cattleianum formed EcM‐like associations when inoculated in sterile culture but not in situ (Freire et al ., ). In both these studies the illustrations of Hartig net provided appear abnormal, so these associations are probably examples of SRH.…”

Comprehensive Analysis of Rhodomyrtus tomentosa Chloroplast Genome

“…The family Myrtaceae has over 3000 species distributed predominantly in tropical and subtropical regions of Australia and America [1]. Within this family, Rhodomyrtus tomentosa , an evergreen shrub of genera Rhodomyrtus, is commonly found in east and southeast Asia, including southern China, Japan, and Thailand [2].…”

Endophytic bacteria associated with tissue culture and leaves of Plinia peruviana

“…Other species of Myrtaceae, such as Campomanesia xanthocarpa O. Berg and Psidium cattleianum Sabine, have already been successfully micropropagated. However, as in most reports on the in vitro tissue culture of woody species, bacterial growth was observed in the explants (Freire et al, 2018;Machado et al, 2020).…”