Comparative photochemical and phenomorphological responses to winter stress of an evergreen (Quercus ilex L.) and a semi-deciduous (Cistus albidus L.) Mediterranean woody species

The impact of winter stress on plants from a Mediterranean area was evaluated through comparison of photosystem II (PS II) efficiencies and phenomorphological characteristics of two Mediterranean woody species – Quercus ilex (evergreen) and Cistus albidus (semi-deciduous). The studies were carried out in NE Spain, at two sites with different mean winter temperatures. The results showed that reductions of the efficiency of PS II may occur in Mediterranean plant communities during winter, and are especially remarkable on colder days. The extent and duration of the decrease in PS II efficiency (photoinhibition) depended not only on the climatic conditions, but also on the site, on the species considered and on the position of leaves in the plant canopy. Increased photoinhibition at the colder site was only clear for C. albidus. Nevertheless, the efficiencies of PS II were always higher in C. albidus than in Q. ilex. Phenological patterns, morphology and leaf inclination may protect C. albidus leaves from potentially photoinhibitory conditions in winter. Morphological and structural photoprotection is apparently not so well developed in Q. ilex, which probably relies more on increased protection at the photochemical level of its long-lived leaves. As has been reported in relation to summer-drought stress, Q. ilex has possibly developed a strategy of tolerance to photoinhibition, whereas C. albidus relies preferentially on avoidance features.     

A comparative study of aboveground biomass of three Mediterranean species in a post-fire succession

The aboveground biomass of three woody species (Cistus albidus, Quercus coccifera and Pinus halepensis) in two early successional stages (3- and 10-year old) of a post-fire Mediterranean ecosystem was investigated. Among these three species, which belong to the successional series of holm oak (Quercus ilex), C. albidus and Q. coccifera are two dominant shrub species in the garrigue ecosystem and P. halepensis is a pioneer tree species widely represented in the Mediterranean area. The results obtained showed that in monospecific stands, C. albidus and Q. coccifera had a high recovery potential. In the 3-year-old stands, the cover of P. halepensis was only 19.8% for a total biomass of 0.75 ± 0.21 t ha^–1, while the plant cover of C. albidus and Q. coccifera was, respectively, 26% and 85.5% and biomass was 4.72 ± 1.09 and 11.5 ± 0.16 t ha^–1. Only 10 years after fire, the plant cover of C. albidus and Q. coccifera was, respectively, 55% and 100% and total biomass 13.2 ± 1.7 and 35.8 ± 4.7 t ha^–1. The greatest increase in biomass was noted for P. halepensis (29.7 t ha^–1). If mean annual biomass increments are considered, it appears that there was a significant decrease with the stand age for the two shrub species although the tree species showed an increase in productivity. These differing patterns in biomass and productivity of shrub and tree species with stand age provide information on biomass accumulation rates of pioneer species in a Mediterranean succession and their importance in the vegetation dynamics.     

Effects of winter cold stress on photosynthesis and photochemical efficiency of PSII of the Mediterranean <Emphasis Type="Italic">Cistus albidus</Emphasis> L. and <Emphasis Type="Italic">Quercus ilex</Emphasis> L.

This study examined the photosynthetic and growth performances of potted plants of Cistus albidus L. and Quercus ilex L. submitted either to natural Mediterranean winter conditions or to mild greenhouse conditions. Plants grown outdoors exhibited lower light and CO₂-saturated CO₂ assimilation rates (A_sat) and apparent quantum yield (_i) than those indoors. Until mid-winter, C. albidus had higher A_sat than Q. ilex, but differences disappeared after a period of severe cold. Maximal photochemical efficiency of PSII (Fv/Fm) measured predawn was higher in C. albidus than in Q. ilex, and decreased throughout the season in outdoor plants. Fv/Fm also decreased at light saturation (A_sat) in both species. Fv/Fm was correlated with photosynthetic capacity and efficiency (quantum yield), but the resulting regression slopes were different between the two species. At the physiological level, C. albidus seemed to cope better with cold stress than Q. ilex. However, winter stress induced reduction of leaf absorptance, increased leaf mass per area, extensive leaf damage and high plant mortality in C. albidus. This suggests that the high performance of C. albidus leaves is not likely to be maintained for long periods of cold stress, and may therefore depend on continuous leaf replacement. Quercus ilex showed a conservative behaviour, with low net assimilation rates but greater leaf and plant survival than C. albidus.     

Potentialités autotoxiques et allélopathiques de Cistus albidus L.

This study focuses on how allelopathic mechanisms may be involved in the floristic composition and dynamics of Cistus albidus shrubbery. Allelopathic potential of essential oils was measured for Lactuca sativa (toxicity for other species) and Cistus albidus (self-toxicity). These oils have little effect on germination but significantly increase, even in low quantities, the number of unviable seedlings and inhibit normal seedling growth. These results explain, at least partially, the existence of monospecific stands over several years and the lack of natural regeneration of the Cistus albidus populations. Bioassays performed using natural aerial leachates of Cistus albidus revealed no significant effects on the above-mentioned parameters. Leaching does not seem to be an important means of allelochemicals release. Nevertheless, essential oils have been quantified in litter and soil, indicating a possible occurrence of allelopathy in such ecosystems.     

Comparative protective strategies of Cistus albidus and Quercus ilex facing photoinhibitory winter conditions

The role of structural photoprotection under photoinhibitory winter conditions was evaluated in two Mediterranean woody species: Cistus albidus (semideciduous) and Quercus ilex (evergreen). Shoots were manipulated in order to modify the light load naturally received by the leaves throughout the cold season, and monitored for changes in maximum photochemical efficiency of PSII, phenology, and leaf morphology. Naturally steep leaves of C. albidus were restrained to a horizontal position, and compared with control leaves (naturally horizontal, or steeply inclined). Fully exposed leaves of Q. ilex were artificially protected through partial shading, and compared with control leaves (not shaded). During the cold season, the most exposed (either naturally or artificially) leaves were always more photoinhibited (had lower maximal photochemical efficiency of PSII) than the photoprotected ones. The differences disappeared at the beginning of spring. Winter photoinhibition was not more pronounced in older than in younger leaves of C. albidus, indicating that inclination rather than age affected their photochemical efficiency. Leaf chlorophyll contents were not significantly affected by the manipulations. Leaf thickness decreased slightly in the least exposed shoots of the evergreen species, but no changes were detected in leaf morphological traits of the semideciduous one. The increased photoinhibitory pressure led only to slight and non-significant changes in phenology and growth.     

A survey method for assessing the richness of epiphytic lichens using growth forms

The species richness of epiphytic lichens is continuously decreasing by degradation and loss of habitat. Considering that taxonomic identification of all species is time and resource consuming, rapid assessment methods to extrapolate the total number of species are needed for practical conservation. This paper describes an alternative method using the correlation between lichens growth forms and species richness. The study was conducted in 406 forest stands located in Central Spain, covering a wide range of mediterranean-climate ecosystem regions, management intensity levels, canopy cover conditions, and tree sizes. The presence/absence of epiphytic lichens was determined in 6090 trees, which were dominated by oak species (Quercus ilex, Q. faginea, and Q. pyrenaica). In all type of forests, the diversity of growth forms was positively correlated with the total epiphytic lichen richness. In all cases, species richness increased in non-managed forest stands with dense canopies. Thus, we propose the use of lichen growth forms as a helpful surrogate of species richness to detect potentially conservation priority areas in the Mediterranean region.     

Germination of Quercus ilex and Q. pubescens in a Q. ilex coppice

Quercus ilex L. (holm oak) coppices, widespread around the Mediterranean basin, are probably the result of 5 000 years of prolonged human disturbance of the original Quercus pubescens Willd. (downy oak) forests. Since disturbance has almost ceased in recent years, a question arises as to the development of these coppices: will the Q. pubescens forests return, or will Q. ilex remain the dominant species? To investigate the phenomenon, we analyzed the first stages, i.e. germination of the two species in holm oak coppices. Our experiments show that both species germinated better in coppices than in clearings or clear-cuts. Moreover, Q. pubescens appears to be slightly favored above Q. ilex and it is suggested auto-allelopathy is involved, at least partially inhibiting the germination of Q. ilex.     

Interspecific variation in functional traits of oak seedlings (<Emphasis Type="Italic">Quercus ilex,Quercus trojana,Quercus virgiliana</Emphasis>) grown under artificial drought and fire conditions

To face summer drought and wildfire in Mediterranean-type ecosystems, plants adopt different strategies that involve considerable rearrangements of biomass allocation and physiological activity. This paper analyses morphological and physiological traits in seedlings of three oak species (Quercus ilex, Quercus trojana and Quercus virgiliana) co-occurring under natural conditions. The aim of this study was to evaluate species-specific characteristics and the response of these oak seedlings to drought stress and fire treatment. Seedlings were kept in a growth chamber that mimicked natural environmental conditions. All three species showed a good degree of tolerance to drought and fire treatments. Differences in specific biomass allocation patterns and physiological traits resulted in phenotypic differences between species. In Q. ilex, drought tolerance depended upon adjustment of the allocation pattern. Q. trojana seedlings undergoing mild to severe drought presented a higher photosystem II (PSII) efficiency than control seedlings. Moreover, Q. trojana showed a very large root system, which corresponded to higher soil area exploitation, and bigger leaf midrib vascular bundles than the other two species. Morphological and physiological performances indicated Q. trojana as the most tolerant to drought and fire. These characteristics contribute to a high recruitment potential of Q. trojana seedlings, which might be the reason for the dominance of this species under natural conditions. Drought increase as a result of climate change is expected to favour Q. trojana, leading to an increase in its spatial distribution.     

Mise en évidence de la dynamique de quelques écosystèmes forestiers et préforestiers provençaux aux étages méditerranéens S.L. à l'aide des taxons indicateurs

Evidence is presented for dynamic successions in the Provence on the basis of a multivariate analysis, of a very large sample. Different phases in the Quercus suber series on silicious substrate are shown. Also the evolution of the vegetation groupings on Ventoux and Sainte-Baume mountains on calcareous substrate and at different levels in the zonation is specified. The succession of the grasslands is as follows: Isoetes and Nasturtium groupings, Serapias, Lotus and Trifolium, then Vulpia and Aira groupings, and finally Helianthemum guttatum grasslands, preceding the shrub groupings: Cistus ladaniferus, then Cistus albidus and Cistus monspeliensis. Then follow either Erica and Calluna maquis or Quercus suber formations. On Mont Ventoux, the stages of degradation of the Quercus pubescens forests are Aphyllantes and Thymus vulgaris grasslands, and Buxus sempervirens and Genista scorpius scrubs. On the oromediterranean level, the transition from Avena setacea and Galium villarsii grasslands, then Ononis caenisia grasslands to Pinus uncinata forests is demonstrated. The development of reforestation is predicted on the basis of the floristic composition of the previous stages. On Sainte-Baume Mountain, the Quercus pubescens supramediterranean series is formed by the following stages: low scrubs of the Lavandulo-Astragaletum, and Prunus mahaleb and Phillyrea media, Acer monspessulanum groves, and forests with prevailing Quercus pubescens. The succession on rocky traverses and crests is slightly different. The first stages are Sesleria grasslands and the later ones are woodland groupings of Tilia platyphyllos, Acer opalus and Ilex aquifolium.     

Field Evidence of Colonisation by Holm Oak,at the Northern Margin of Its Distribution Range,during the Anthropocene Period

A major unknown in the context of current climate change is the extent to which populations of slowly migrating species, such as trees, will track shifting climates. Niche modelling generally predicts substantial northward shifts of suitable habitats. There is therefore an urgent need for field-based forest observations to corroborate these extensive model simulations. We used forest inventory data providing presence/absence information from just over a century (1880–2010) for a Mediterranean species (Quercus ilex) in forests located at the northern edge of its distribution. The main goals of the study were (i) to investigate whether this species has actually spread into new areas during the Anthropocene period and (ii) to provide a direct estimation of tree migration rate. We show that Q. ilex has colonised substantial new areas over the last century. However, the maximum rate of colonisation by this species (22 to 57 m/year) was much slower than predicted by the models and necessary to follow changes in habitat suitability since 1880. Our results suggest that the rates of tree dispersion and establishment may also be too low to track shifts in bioclimatic envelopes in the future. The inclusion of contemporary, rather than historical, migration rates into models should improve our understanding of the response of species to climate change.     

Management of nursery practices for efficient ectomycorrhizal fungi application in the production of Quercus ilex

The application of ectomycorrhizal (ECM) fungi on forest nursery production is regarded as part of good management practice. However, before employing large scale inoculations in a nursery the interaction between ECM symbionts, growth substrate and fertilisation input should be studied to select the most suitable nursery practices for promoting plant growth and ECM colonisation. In this study, seedlings of Quercus ilex were inoculated with Paxillus involutus, Hebeloma mesophaeum or Cenococcum geophilum and grown in three different substrates commonly used in forest nurseries: peat-based compost, forest soil or composted pine bark. The effect of various fertilisation regimes was also studied. The choice of substrate had a significant effect on plant growth and ECM colonisation. The most appropriate combination of substrate and ECM fungus for Q. ilex growth and nutrition was peat and H. mesophaeum. Plants grown on a peat-based compost and inoculated with H. mesophaeum had a significantly greater biomass and leaf phosphorus concentration without fertilisation. Composted pine bark was found not to be suitable for growth or for mycorrhization. If the appropriate growth substrate is selected, it is possible to replace the use of chemical fertilisers by inoculation with selected ECM fungi. This results in a significant increase in plant development, and thus ECM fungi can be recommended as a more environmental friendly biotechnological approach to plant management in the nursery.     

Differential field response of two Mediterranean tree species to inputs of sewage sludge at the seedling stage

Land degradation and desertification is a common feature in Mediterranean landscapes due to extensive and intensive land use and natural or man induced disturbances. The ecosystem may need external inputs to recover its composition and function as soils are often impoverished and vegetal key stone species lost. We evaluated the effects of the application of fresh and air-dried biosolids in the establishment and morphological and physiological performance of seedlings of Pinus halepensis and Quercus ilex under dry Mediterranean field conditions. Seedling survival was not affected by biosolid treatments in any of the studied species both two and ten years after planting. During the first two years, growth was enhanced by the two biosolid treatments in relation to control, although the change in the biomass allocation pattern differed between species. Rooting depth was significantly enhanced by liquid biosolid in Q. ilex and marginally reduced in P. halepensis as well as the exploration of soil. As a consequence, root-to-shoot ratio reduced significantly with dry and liquid sludge due to promoted aboveground growth while maintaining and even reducing belowground fractions. An improvement of the nutritional status, of fertilized seedlings especially of phosphorus, is the explanation for the better field performance. Vector analysis revealed an important phosphorus limitation for both species that was overcome with the application of liquid (both species) and air-dried biosolid (pine). The higher growth of pine seedlings attained in the liquid biosolid treatment was coupled with a significant decrease in foliar δ¹³C, suggesting lower water use efficiency. The significant increase in foliar δ¹⁵N in the biosolid treatments in both species suggested that a large proportion of the total nitrogen uptake came from the applied biosolids. Instead, with regard to the low biosolid application rate used in the study, treatments had an overall positive effect as a restoration tool by improving nutritional status and promoting growth of planted seedlings.     

Herbivory in a Mediterranean forest: browsing impact and plant compensation

The compensatory response of plants to defoliation is likely to have important effects on plant–ungulate equilibria in forested ecosystems. We investigated the responses of six species of Mediterranean bushes to defoliation by wild ungulates, comparing an index of browsing impact with the productivity of plants in both open and exclusion plots. The data revealed a great diversity of plant responses to herbivory: Rubus ulmifolius was able to over-compensate and replace the lost tissues. Phillyrea latifolia exhibited a similar, albeit less evident, pattern, while Cistus salvifolius was severely damaged by browsing. Other species, such as Quercus ilex, Juncus acutus and Erica arborea, were not attacked to a large extent and suffered little or no harm. The results strongly suggest that Mediterranean ecosystems may tolerate large stocking rates of ungulates. However, the reduction of plant biomass due to browsing was very different in the six studied species, suggesting that when herbivory becomes severe the structure of the ecosystem will change with the more tolerant plants becoming more abundant. We can apply these results to improve management and conservation of relict coastal forests in the Mediterranean basin which are usually of small size and where decision-makers have to compromise between the conservation of plants and that of large mammals.     

Effects of forest management on epiphytic lichen diversity in Mediterranean forests

Question: What are the responses of epiphytic lichens to the intensity of management along a large environmental gradient in Mediterranean Quercus forests? Location: Central Spain. Methods: This study was carried out on 4590 trees located in 306 forest stands dominated by Quercus faginea or Quercus ilex ssp. ballota. The effect of forest management and other predictor variables on several species diversity indicators were studied. Variables modelled were total species richness, cyanolichen richness and community composition. A large number of predictor variables were included: forest fragmentation (patch size, stand variability), climate and topographic (altitude, slope, sun radiation, annual rainfall and mean annual temperature) and intensity of management. General linear models and constrained ordination techniques were used to model community traits and species composition, respectively. Results: Total richness and especially cyanolichens richness were significantly and negatively affected by the intensity of management. Lichen composition was influenced by management intensity, climatic and topographic variables and stand variability. Conclusions: In Mediterranean forests, human activities related to forestry, agricultural and livestock use cause impoverishment of lichen communities, including the local disappearance of the most demanding species. The conservation of unmanaged forests with a dense canopy is crucial for lichen diversity.     

Morphological characterization of mycorrhizae formed between three Terfezia species (desert truffles) and several Cistaceae and Aleppo pine

Six Cistaceae species, Helianthemum ledifolium, Helianthemum lippii, Fumana procumbens, Cistus albidus, Cistus incanus, Cistus salvifolius, and Pinus halepensis (Aleppo pine) were inoculated with three mycorrhizal desert truffles, Terfezia leptoderma, Terfezia boudieri, and Terfezia claveryi under greenhouse conditions, on soil originating from desert truffle natural habitat in Algeria. The syntheses have led to the formation of typical endomycorrhizae in annual Cistaceae (H. ledifolium) and perennial ones (H. lippii and F. procumbens) and an ectomycorrhiza with a less developed sheath in Cistus species and Aleppo pine. These results demonstrate the plasticity of Terfezia species to form different mycorrhizal types. The formation of an endomycorrhiza with H. ledifolium and F. procumbens and a sheathing ectomycorrhiza with P. halepensis inoculated by T. leptoderma in in vivo culture conditions was obtained for the first time.     

The efficiency of nitrogen retranslocation from leaf biomass in Quercus ilex ecosystems

Nitrogen retranslocation from senescing leaves represents a crucial adaptation by tree species towards a more efficient use of this nutrient. As a result, this part of the nitrogen cycle has received increasing attention in recent years. However, there remain strong discrepancies with respect to the factors responsible for interspecific differences in the efficiency of this process.In the present work the seasonal pattern of leaf growth and the movement of nitrogen in leaves have been studied in a series of Quercus ilex plots with different levels of rainfall and soil quality in central-western Spain, as well as in 20 other woody species typical of this area. The percentage of nitrogen retranslocated was estimated from the difference between the maximum mass of nitrogen stored in the leaf biomass and the amount of this nutrient returned annually to the soil through leaf fall. Q. ilex appears as one of the least efficient species in the Mediterranean region in the recovery of nitrogen from senescing leaves (29.7% of the maximum pool). Furthermore, the older leaves of Q. ilex do not show the cycles of nitrogen withdrawal during new flushes of shoot growth, such as occurs in Pinus spp. This suggests that older leaves in Q. ilex do not play an important role as nitrogen storage organs.     

Tree growth,mortality, and above-ground biomass accumulation in a holm oak forest under a five-year experimental field drought

A holm oak forest was exposed to an experimental drought during 5 years to elucidate the growth responses of the dominant species Quercus ilex, Arbutus unedo and Phillyrea latifolia. Soil water availability was partially reduced, about 15% as predicted for this area for the next decades by GCM and ecophysiological models, by plastic strips intercepting rainfall and by ditch exclusion of water runoff. The stem diameter increment was highly correlated with annual rainfall in all species, and drought treatment strongly reduced the diameter increment of Q. ilex (41%) and specially of A. unedo (63%), the species showing higher growth rates. Stem mortality rates were highly correlated with previous stem density, but drought treatment increased mortality rates in all species. Q. ilex showed the highest mortality rates (9% and 18% in control and drought plots, respectively), and P. latifolia experienced the lowest mortality rates (1% and 3% in control and drought plots, respectively). Drought strongly reduced the increment of live aboveground biomass during these 5 years (83%). A. unedo and Q. ilex experienced a high reduction in biomass increment by drought, whereas P. latifolia biomass increment was insensitive to drought. The different sensitivity to drought of the dominant species of the holm oak forest may be very important determining their future development and distribution in a drier environment as expected in Mediterranean areas for the next decades. These drier conditions could thus have strong effects on structure (species composition) and functioning (carbon uptake and biomass accumulation) of these Mediterranean forests.     

Root Morphology, Stem Growth and Field Performance of Seedlings of Two Mediterranean Evergreen Oak Species Raised in Different Container Types

Outplanting container-grown oak seedlings with undesirable shoot and root characteristics result in poor establishment and reduced field growth. The objective of this study was to determine the influence of container type on both above-and below-ground nursery growth and field performance of one-year old tap-rooted seedlings Quercus ilex L. and Quercus coccifera L. The experiment was conducted in an open-air nursery and the seedlings were grown in three container types. At the end of the nursery, growth period seedlings’ shoot height, diameter (5 mm above root collar), shoot and root biomass, root surface area, root volume and total root length were assessed. Then the seedlings were planted in the field and their survival and growth were recorded for two growing seasons after outplanting. The results showed a difference between the Quercus species in the effect of container type. Q. ilex seedlings raised in paper-pot had significantly greater height, diameter, shoot and root biomass and root volume than those raised in the other two container types. Similarly, Q. coccifera seedlings raised in paper-pot, had significantly greater above-and below-ground growth than those raised in the other two container types. Both oak species showed relatively low survival in the field; the mortality was mainly observed the first year after outplanting, especially after the summer dry period. However, 2 years after outplanting, the paper-pot seedlings of the two oak species showed better field performance.     

Is Shade Beneficial for Mediterranean Shrubs Experiencing Periods of Extreme Drought and Late-winter Frosts?

Background and Aims

Plants are naturally exposed to multiple, frequently interactive stress factors, most of which are becoming more severe due to global change. Established plants have been reported to facilitate the establishment of juvenile plants, but net effects of plant–plant interactions are difficult to assess due to complex interactions among environmental factors. An investigation was carried out in order to determine how two dominant evergreen shrubs (Quercus ilex and Arctostaphylos uva-ursi) co-occurring in continental, Mediterranean habitats respond to multiple abiotic stresses and whether the shaded understorey conditions ameliorate the negative effects of drought and winter frosts on the physiology of leaves.

Methods

Microclimate and ecophysiology of sun and shade plants were studied at a continental plateau in central Spain during 2004–2005, with 2005 being one of the driest and hottest years on record; several late-winter frosts also occurred in 2005.

Key Results

Daytime air temperature and vapour pressure deficit were lower in the shade than in the sun, but soil moisture was also lower in the shade during the spring and summer of 2005, and night-time temperatures were higher in the shade. Water potential, photochemical efficiency, light-saturated photosynthesis, stomatal conductance and leaf ¹³C composition differed between sun and shade individuals throughout the seasons, but differences were species specific. Shade was beneficial for leaf-level physiology in Q. ilex during winter, detrimental during spring for both species, and of little consequence in summer.

Conclusions

The results suggest that beneficial effects of shade can be eclipsed by reduced soil moisture during dry years, which are expected to be more frequent in the most likely climate change scenarios for the Mediterranean region.Key words: Frost, climate change, shade, drought, plant–plant interactions, Quercus ilex, Arctostaphylos uva-ursi, soil moisture, facilitation     

Synthesis and establishment of <Emphasis Type="Italic">Tuber melanosporum</Emphasis> Vitt. ectomycorrhizae on two <Emphasis Type="Italic">Nothofagus</Emphasis> species in Chile

Axenically germinated seedlings of two species of Southern beech (Nothofagus obliqua, N. glauca) from Chile were inoculated with spores of the Périgord black truffle (Tuber melanosporum). Ectomycorrhizal development was monitored for 6 months in the greenhouse and compared to the performance of the natural host species Quercus ilex and Quercus robur. Seedling survival and mycorrhization showed major differences in both Nothofagus species: T. melanosporum readily formed ectomycorrhizae with seedlings of N. obliqua, although at a lower rate than with Q. ilex but at a proportion very similar to Q. robur; survival and colonization rates were high, and seedling growth was not visibly affected by the high soil pH required by T. melanosporum. In contrast, more than 50% of N. glauca seedlings died after inoculation, and mycorrhiza formation was very sparse. In both species, no colonization by adventive ectomycorrhizal fungi could be observed, whereas both species of Quercus showed minor colonization by another fungus, probably Inocybe or Hebeloma. Our results show that it is possible to infect N. obliqua with the Périgord black truffle under greenhouse conditions, which opens up the possibility of cultivating this truffle as a secondary crop during reforestation with N. obliqua in Chile.