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891.
Maria Isabel Cuestas Maria Angela Martin Hani Kassim Aldebis Juan Diego Mena Luis Miguel Martin Enrique Vargas-Osuna 《Entomologia Experimentalis et Applicata》2020,168(3):259-265
Fruit production of Castanea sativa Miller (Fagaceae) in southern Spain is carried out in traditional orchards using a large number of local varieties. The main areas of production are located in the Natural Park of Sierra de Aracena y Picos de Aroche (Huelva) and the Genal river Valley (Malaga). These agroforestry systems have shown a high genetic diversity and represent an example of in situ conservation. In this region, chestnut mainly suffers from attacks by Cydia splendana (Hübner) (Lepidoptera: Tortricidae), whose larvae feed on the fruits, thereby reducing their quality and economic value. The aim of this study was to evaluate the differential response between the chestnut local varieties to the attack of C. splendana. For that purpose, trees from the most representative varieties were evaluated on various farms. In cases where it was necessary, the trees were identified with a set of eight microsatellite markers. The infestation rate of C. splendana (percentage of infested fruits of the total fruits sampled per tree) differed among varieties, indicating a high genetic component in this effect. The results obtained in this study open the possibility of using this differential response in the control of C. splendana. 相似文献
892.
893.
Cecilia Smith-Ramírez Iván Díaz Patricio Pliscoff Claudio Valdovinos Marco A. Méndez Juan Larraín Horacio Samaniego 《Biodiversity and Conservation》2007,16(9):2627-2648
Knowledge of species richness centers is necessary for the design of conservation areas. In this study, we present a GIS analysis
of two years of field data on animal and plant diversity distributions in evergreen, coastal rain forests of southern Chile
(39°30′–41°25′ S). Despite their high endemism, these forests have remained largely unprotected. Field records were complemented
with data from museum collections and scientific literature. We used selected environmental variables (evapotranspiration,
altitude) and, in some cases, forest types as predictors of species distributions. Our study focused on the distribution of
forest bryophytes, vascular plants, soil invertebrates, amphibians and birds. We generated distributional maps for each taxa
based on their field records in the study area, complemented by natural history information, except in the case of bryophytes
and soil invertebrates. In general, species richness was lower at 600 m elevation or above for all the taxa studied. Species
richness tends to increase in the northern sector of the study area. We observed a greater richness of vascular plants near
rivers and streams, and noted important floristic differences between west and east-facing slopes of the Coastal Range, with
more species in the oriental side. Because species in high altitude forests are not a subset of those found at lower elevations,
we propose that conservation strategies should prioritize the protection of the entire altitudinal gradient of the southern
Coastal Range, especially in the more diverse oriental and northern sectors. 相似文献
894.
We detected that Galaxias maculatus exhibits a pattern where metabolic activity increases after sunrise and peaks between noon and sunset, but this species feeds in the afternoon, until several hours after sunset. Moreover, we showed that G. maculatus is observed in the littoral zone during the day, disappears completely from this zone after sunset and returns at sunrise. Littoral prey species are common in the diet of G. maculatus, but this study showed that pelagic prey is also present during twilight and night hours in smaller individuals (<50 mm), which is related to habitat use. These behavioural rhythms are especially important for G. maculatus, which runs a high predation risk when consuming prey that is widely available outside the littoral zone. This risk is ameliorated under the protection of low light intensity. Thus, G. maculatus is a key species linking lower trophic levels, such as the plankton community, to higher levels of native and exotic piscivores. These displacements of G. maculatus generate an active flow of energy and matter between habitats, with a potentially profound effect on the entire food network and energy dynamics of the lake. 相似文献
895.
896.
B. Fontaine Sophie Nicole Haluk Topaloglu C. Ben Hamida Peter Beighton Frank Spaans Jose M. A. Cantu Salim Bakouri Norma Romero K. Ricker Patricio Barros-Nunez Gérard Ponsot M. Ben Hamida Jean Weissenbach F. Hentati Frank Lehmann-Horn 《Human genetics》1996,98(3):380-385
Schwartz-Jampel syndrome (SJS), or chondrodystrophic myotonia, is a rare autosomal recessive disorder characterized by generalized
myotonia resulting in a particular, recognizable facies and osteoarticular abnormalities. Some of us have recently shown genetic
linkage of SJS to a locus on 1p34–p36.1 in five families. Here, we show by homozygosity mapping and segregation analysis that
eight new families are most likely linked to the SJS locus on chromosome 1, confirming the localization of SJS to chromosome
1p and suggesting genetic homogeneity. Recombination events reduced the SJS locus from a genetic interval of 8 to 3 cM, which
should facilitate the identification of the SJS gene. Low clinical variability was observed between the studied families,
except for osteoarticular abnormalities. Since the severity and the location of osteoarticular abnormalities varied from one
individual to another, even in the same families, other factors than the SJS gene itself, genetic or epigenetic, might contribute
to the phenotype.
Received: 11 February 1996 / Revised: 6 April 1996 相似文献