Infant Responding to Joint Attention, Executive Processes, and Self-Regulation in Preschool Children

Infant joint attention is related to behavioral and social outcomes, as well as language in childhood. Recent research and theory suggests that the relations between joint attention and social–behavioral outcomes may reflect the role of executive self-regulatory processes in the development of joint attention. To test this hypothesis two studies were conducted. The first, cross-sectional study examined the development of responding to joint attention (RJA) skill in terms of increasing executive efficiency of responding between 9 and 18 months of age. The results indicated that development of RJA was characterized by a decreased latency to shift attention in following another person\u27s gaze and head turn, as well as an increase in the proportion of correct RJA responses exhibited by older infants. The second study examined the longitudinal relations between 12-month measures of responding to joint attention and 36-month attention regulation in a delay of gratification task. The results indicated that responding to joint attention at 12-months was significantly related to children\u27s use of three types of self-regulation behaviors while waiting for a snack reward at 36 months of age. These observations are discussed in light of a developmental theory of attention regulation and joint attention in infancy

Quercirhiza quadratum: a revision of the characters and identity of the ad type ectomycorrhiza

The well-known AD type, described first by Giraud in 1988, is considered as a competitor in black truffle (Tuber melanosporum Vittad.) plantations. It has been mainly observed in T. melanosporum and T. magnatum Pico plantations in France and Italy. This ectomycorrhiza has always been observed on roots of oak (Quercus ilex L. and Q. faginea Lam.) and hazelnut (Corylus avellana L.) plantations with “burnt” areas around the trees, even in those that do not produce black truffle sporocarps, so it can create false expectations in young plantations. The AD type has also been described in nurseries, as a competitive ectomycorrhiza on seedlings inoculated with black truffle. In Spain, AD type has been detected in black truffle plantations and natural holm oak stands in Navarra, Soria, Huesca, Zaragoza, Teruel, Castellón and Valencia. In 2005, De Román & De Miguel, suggested that AD type could be a telephoroid type due to its anatomical and morphological characters. In 2006, Baciarelli-Falini et al. using molecular techniques identified this type as an Ascomycotina belonging to Pezizales. The detailed anatomical, morphological and molecular study of the AD type led to a description as Quercirhiza quadratum (Águeda et al. 2008). Based on the anatomical and morphological characters, the AD type belongs to the Ascomycotina. The presence of Woronin bodies on hyphal septa, and the sometimes slightly dissolved septa, are two typical characters of this group. The DNA sequences obtained from the AD types studied showed close similarities with members of Pyronemataceae and Sarcosomataceae (Pezizales). Both taxonomic groups correspond to the same AD type as found by Baciarelli Falini et al., (2006). One of the studied sequences showed a close identity (100% maximum identity, 84% coverage) with Trichophaea woolhopeia (Cooke & W. Phillips) Arnould, although records of this fungal species are scarce in the Iberian Peninsula

Characterization and identification of field ectomycorrhizae of Boletus edulis and Cistus ladanifer

Field ectomycorrhizae sampled under Boletus edulis and Cistus ladanifer have been characterized and described in detail based on standard morphological and anatomical characters. The described ectomycorrhiza has traits typical of Boletales: whitish with three differentiated plectenchymatous layers in the mantle in plan view forming ring-like structures and rhizomorphs with highly differentiated hyphae. The inflated, smooth cystidia-like clavate end cells on the surface of the rhizomorphs and their slightly twisted external hyphae are additional characterizing features. The Hartig net occupies 1 1/2 rows of cortical cells, partly reaching the endodermis. Not all hyphae have clamps. The identification of the fungal symbiont as B. edulis was confirmed by ITS rDNA sequence comparison between mycorrhizas and sporocarps. The singularity of this symbiotic association, as well as its ecological and practical implications, are discussed

Síntesis de ectomicorrizas entre Cistus sp. y las especies del complejo Boletus edulis

En los jarales resultantes de la reiteración de incendios forestales en el oeste de Castilla y León (León, Salamanca y Zamora) es habitual la presencia de fructificaciones de Boletus edulis Bull. La recolección de estos hongos micorrícicos comestibles en los jarales dominados exclusivamente por Cistus ladanifer, supone una oportunidad económica alternativa a los usos tradicionales para zonas con bajos ingresos procedentes del monte. El objetivo de éste trabajo es la obtención de ectomicorrizas de las especies del complejo B. edulis con Cistus sp. bajo condiciones controladas, y las descripciones anatómicas detalladas de las mismas. La identificación de los aislados fúngicos de Boletus aereus Bull., B. edulis, B. reticulatus Schaeff. y B. pinophilus Pilát & Dermek fue confirmada por métodos moleculares. Se han obtenido ectomicorrizas de Boletus aereus, B. edulis y B. reticulatus con Cistus albidus L. y C. ladanifer en condiciones de síntesis en cultivo puro, en un substrato de turbavermiculita estéril y solución nutritiva. Las ectomicorrizas formadas se describieron siguiendo los caracteres anatómicos y morfológicos habituales. Las tres ectomicorrizas son muy similares, de color blanco, con ramificación monopodial-pinnada, manto formado por tres capas plectenquimatosas y con rizomorfos de tipo boletoide

Receptiveness of forest soils to ectomycorrhizal association: I. concept and method as applied to the symbiosis between Laccaria bicolor (maire)orton and Pinus pinaster art or Pseudotsuga menziesii (Mirb) franco

International audienc

Réceptivité des sols forestiers à l'association ectomycorhizienne. Application à la définition de la compétence écologique de souches sélectionnées

National audienc

Receptivite des sols forestiers a l'association ectomycorhizienne. Application a la definition de la competence ecologique de souches selectionnees

National audienc

Quercirhiza quadratum: a revision of the characters and identity of the ad type ectomycorrhiza

The well-known AD type, described first by Giraud in 1988, is considered as a competitor in black truffle (Tuber melanosporum Vittad.) plantations. It has been mainly observed in T. melanosporum and T. magnatum Pico plantations in France and Italy. This ectomycorrhiza has always been observed on roots of oak (Quercus ilex L. and Q. faginea Lam.) and hazelnut (Corylus avellana L.) plantations with “burnt” areas around the trees, even in those that do not produce black truffle sporocarps, so it can create false expectations in young plantations. The AD type has also been described in nurseries, as a competitive ectomycorrhiza on seedlings inoculated with black truffle. In Spain, AD type has been detected in black truffle plantations and natural holm oak stands in Navarra, Soria, Huesca, Zaragoza, Teruel, Castellón and Valencia. In 2005, De Román & De Miguel, suggested that AD type could be a telephoroid type due to its anatomical and morphological characters. In 2006, Baciarelli-Falini et al. using molecular techniques identified this type as an Ascomycotina belonging to Pezizales. The detailed anatomical, morphological and molecular study of the AD type led to a description as Quercirhiza quadratum (Águeda et al. 2008). Based on the anatomical and morphological characters, the AD type belongs to the Ascomycotina. The presence of Woronin bodies on hyphal septa, and the sometimes slightly dissolved septa, are two typical characters of this group. The DNA sequences obtained from the AD types studied showed close similarities with members of Pyronemataceae and Sarcosomataceae (Pezizales). Both taxonomic groups correspond to the same AD type as found by Baciarelli Falini et al., (2006). One of the studied sequences showed a close identity (100% maximum identity, 84% coverage) with Trichophaea woolhopeia (Cooke & W. Phillips) Arnould, although records of this fungal species are scarce in the Iberian Peninsula

The ability of a host plant to associate with different symbiotic partners affects ectomycorrhizal functioning

Some plants that associate with ectomycorrhizal (ECM) fungi are also able to simultaneously establish symbiosis with other types of partners. The presence of alternative partners that may provide similar benefits may affect ECM functioning. Here we compared potential leucine-aminopeptidase (LA) and acid phosphatase (AP) enzyme activity (involved in N and P cycling, respectively) in ECM fungi of three hosts planted under the same conditions but differing in the type of partners: Pinus (ECM fungi only), Eucalyptus (ECM and arbuscular mycorrhizal -AM- fungi) and Acacia (ECM, AM fungi and rhizobial bacteria). We found that the ECM community on Acacia and Eucalyptus had higher potential AP activity than the Pinus community. The ECM community in Acacia also showed increased potential LA activity compared to Pinus. Morphotypes present in more than one host showed higher potential AP and LA activity when colonizing Acacia than when colonizing another host. Our results suggest that competition with AM fungi and rhizobial bacteria could promote increased ECM activity in Eucalyptus and Acacia. Alternatively, other host-related differences such as ECM community composition could also play a role. We found evidence for ECM physiological plasticity when colonizing different hosts, which might be key for adaptation to future climate scenarios