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The cork oak (Quercus suber L.) forests are ecosystems of high environmental and socioeconomic value in the Mediterranean basin. However, in Algeria, the cork oak forests are highly threatened by repeated fires, overgrazing and the anthropogenic pressure that weaken the ecosystem of cork oak and affect its natural regeneration. This degradation results in an alteration of many ecological components of the cork oak, such as fungal communities in the soil. Thus, the aim of this work is to study the effects of cork oak stand degradation on the diversity of mycorrhizal communities associated with Quercus suber and some of its understory shrubs (Cistus monspeliensis, Lavandula stoechas and Thymus vulgaris) in the forest of Brabtia (northeastern Algeria).For this purpose, two sites were chosen: one degraded by the anthropogenic factors and the other non-degraded one. Moreover, it is suggested that some plants of the understory shrub vegetation of cork oak, such as the cistus, lavender and thyme, prove to be favourable to the juvenile growth of this tree. The results obtained showed that the ectomycorrhizal (EcM) root colonization of cistus was higher compared to that of cork oak in both stations. The estimation of arbuscular mycorrhizal (AM) colonization showed significantly higher levels in the roots of cork oak, cistus, lavender and thyme in the degraded station compared with the non-degraded stations. In contrast, the rhizosphere soils of cork oak and cistus had low number of AM propagules and fungal spores, while under the roots of lavender and thyme, these two parameters were greatly improved with the abundance of the genera Glomus and Gigaspora. These results underline the need to take into account the plant–fungus interactions in the development of restoration strategies of the degraded soils and forest ecosystems.

Eight new species presented are Calostoma areolatum collected in Wuyishan National Park (China), Crinipellis bidens from Hubei Province (China), Lactifluus sainii from Himalayan India, Inocybe elata from Yunnan (China), Inocybe himalayensis from Pakistan. Specimens previously identified as Massalongia carnosa represent a new species, namely M. patagonica restricted to southern South America. Saprolegnia maragheica is a new oomycete species of fresh water in Maraghe (Iran). Uncispora wuzhishanensis is a new aquatic hyphomycete species. A type specimen of Raddetes turkestanicus was studied and based on this the new combination Conocybe turkestanica, is proposed. Argyranthemum frutescens is a new host for Alternaria alternata and Syzygium cumini for Phyllosticta capitalensis in India. Crepidotus ehrendorferi is confirmed for Hungary and Pluteus leucoborealis for Central Europe, and for the phytogeographical region of Carpaticum. Pseudopithomyces palmicola is shown to occur on grapevine and it is validated by adding a unique identifier. Terfezia fanfani is reported first from Algeria.

In Algeria, often, serious imbalances of the forest ecosystems caused by the badly led exploitations, the repeated fires, the overgrazing involve the disappearance of the timbered state on vast territories. Within the framework of the plantation and restoration programs of these degraded forests, we plan to contribute to it by tests of controlled mycorrhization of forest tees in nursery. But to realize these tests, it is necessary to know beforehand the natural symbiotic status of the studied species. We present there, the first stage of our work which consisted in establishing the mycorrhizal status of main spontaneous or introduced forest species into Algerian North-east. The study was carried out in El Tarf province and related to all the species of pine, oaks and other leafy trees existing in this area. The results show that all the species observed have either ectomycorrhizas (ECM) or arbuscular endomycorrhizas (AM) or both at the same time. In addition, the introduced species of the Acacia or Casuarina genus carry AM and also nitrogen fixing nodules. It should be noted the remarkable diversity of ectomycorrhizal morphotypes associated to the pines and to the oaks and also that of the endomycorhizals fungi spores occur in the rhizosphere of other species. Lastly, it is significant to note the omnipresence of Cenococcum geophilum mycorrhiza in all the stations and the majority of the ectomycorrhizal trees