Search

Objective: To determine the effect of mycelial disturbance on the formation of sporomes of two edible ectomycorrhizal fungi of great biocultural relevance in Mexico (Laccaria laccata and Hebeloma leucosarx) associated to two Neotropical pines with economic and ecological importance, Pinus greggii and P. montezumae. Design/Methodology/Approach: Spore inoculum was produced using ground pilei of the evaluated ectomycorrhizal fungi; each pine plant was inoculated with 107 to 108 fungal spores. A completely randomized experimental design was used with four treatments and six replicates per treatment for each pine species, having a total of 48 experimental units, each one consisting in an inoculated tree. During two years the sporome production was evaluated in the treatments with and without mycelial disturbance. The duration of the experiment, since seed germination, was 5 years. Results: The mycelial disturbance originated a higher formation of sporomes in both fungal species, regardless of the associated tree species. The highest sporome formation was recorded in plants inoculated with H. leucosarx compared to those inoculated with L. laccata in both pine species. Mycelial disturbance, originated a higher number of sporomes in Pinus greggii compared to P. montezumae. Study Limitations/Implications: The evaluation of factors influencing sporome formation in edible ectomycorrhizal fungi requires long term experiments. Findings/Conclusions: This study shows for the first time that mycelial disturbance increases sporome formation in Neotropical ectomycorrhizal fungi. Additionally, a differential influence of the fungal and tree species on the number of produced sporomes was found. These findings shed some light on potential cultivation methods for edible ectomycorrhizal mushrooms. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Ciencias Agrícolas is the property of Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Terrestrial plant roots exude compounds that promote the proliferation of microorganisms, a phenomenon called the rhizosphere effect. However, little is known about the influence of roots of aquatic plants on microbial populations. We compared cultivable bacteria and protozoa from the rhizoplanes ofAzolla filiculoidesLam.,Lemna gibbaL., andRicciocarpus natansL., collected at the Tecocomulco Lagoon (Hidalgo, Mexico). The functional bacterial groups isolated fromA. filiculoides,L. gibbaandR. natans, were macro- and microscopically characterized, and phylogenetically identified using the 16S rDNA gen. About 96% of isolates corresponded to Gram-negative bacteria, and potential N-fixing free-living bacteria (diazotrophic bacteria) were the most abundant. Molecular analysis detected 15 bacterial genera in the rhizoplane ofR. natans, whereasA. filiculoidesandL. gibbaonly yielded five genera, among whichAeromonaswas predominant. Twenty-five genera of flagellated and 20 genera of ciliated protozoa were identified.Bodowas the more abundant flagellated, whereasHalteriawas the most frequent ciliate. All three aquatic plants showed the rhizospheric effects. The most abundant and diverse community of protozoa was found inA. filiculoides, which also had the most abundant bacterial community, but the highest bacterial diversity was found inR. natans. [ABSTRACT FROM PUBLISHER]