Contrasted Genetic Diversity, Relevance of Climate and Host Plants, and Comments on the Taxonomic Problems of the Genus Picoa (Pyronemataceae, Pezizales)

Abstract

The species concept within the genus Picoa Vittad. is here revisited in light of new molecular and ecological data obtained from samples collected throughout the Mediterranean basin. Two highly diverse widespread clades and four additional minor lineages were significantly supported by three genes dataset (ITS, 28s LSU and RPB2) inferences for 70 specimens. The two widespread clades occur in very different geographical and ecological areas associated with exclusive host plants in the genus Helianthemum. SEM study of spore surface morphology in these lineages revealed the existence of smooth ascospores in the majority of these clades. However the most frequent lineage in Europe and coastal North Africa displayed either smooth or verrucose spores. Hence this morphological criterion cannot be reliably used to discriminate between the different clades. In addition, SEM observations made on ascospores from several original collections of P. juniperi and P. lefebvrei supported the hypothesis that ornamentation depends on the degree of maturity in some of these lineages. Geographical and ecological, rather than morphological data are here suggested as the most useful characters to separate the different lineages in Picoa. Further studies focusing on these features are needed before the names P. juniperi and P. lefebvrei can be unambiguously linked with the genetic lineages observed.

Ecology and distribution of desert Truffles in Algeria.

“…Surveys were carried out at various sites from January to March during thirty growing season of desert tru es to collect ascomata samples and to note some ecological factors of these hypogeous fungi. The location of studied sites was based on our investigations (Fortas 1990;Fortas and Chevalier 1992;Cha and Fortas 1999;Cha et al 2004;Dib-Bellahouel and Fortas 2011;Zitouni et al 2014Zitouni et al , 2015Zitouni et al , 2018 with the effective help of the nomadic population, local inhabitants and seasonal collectors of these mushrooms, especially in the wide steppic and Saharan regions. Literature devoted to Algerian desert tru es (Chatin 1891 a, b;Maire 1907) also guided us to localize some producing sites in High steppe Plains and Saharan areas although some of them have undergone various anthropogenic factors (overgrazing, land clearing, reforestation, urbanization,...etc.)…”

“…The third macro-micromorphological and phylogenetic study was conducted on thirty-four Picoa taxa from this Algerian collection and several taxa from different countries located around the Mediterranean basin. These analyses improve our understanding of the biogeographical and phylogenetic relationships between different lineages of Picoa (Zitouni-Haouar et al 2015). Macromorphological characteristics were recorded from fresh ascocarps (size, colour, gleba, peridium thickness).…”

“…Two lineages of Picoa (Zitouni-Haouar et al 2015), the Lineage II of Picoa (= P. juniperi Vittad.) with verrucose spores is harvested near H. lippii in the same habitats as T. claveryi and rarely in Saharan area.…”

“…In Algeria, three genera Terfezia, Tirmania and Picoa were collected in different bioclimatic regions near annual or perennial Helianthemum spp. (Chatin 1891 a, b;Maire, 1907;Duggar and Pinoy 1907;Fortas 1990;Fortas and Chevalier 1992;Cha et al 2004;Bradai et al 2014;Zitouni et al 2014Zitouni et al , 2015Zitouni et al , 2018. However, their development is irregular and their abundance depends on the distribution and intensity of rainfall, physicochemical composition of soil and host plants..This study focuses maintly on geographical distribution of desert tru es in Algeria, their diversity and their ecological requirements during growing seasons according to eld surveys carried out during thirty years in several bioclimatic zones.…”

Genetic diversity of the genus Terfezia (Pezizaceae, Pezizales): New species and new record from North Africa

“…The large ribosomal subunit (28S rDNA) was amplified using the primers pair LR0R-LR5 (Vilgalys & Hester 1990, Cubeta et al 1991. PCR amplifications were performed as described by Zitouni-Haouar et al (2015). Amplification products were loaded in 1% agarose gels stained with GelRed Nucleic Acid Gel Stain (Biotium, Hayward, CA, USA) and visualized with a UV transilluminator.…”