Search results for "Forestry"
showing 10 items of 1998 documents
Estimating the genetic diversity and structure ofQuercus trojanaWebb populations in Italy by SSRs: implications for management and conservation
2017
Studying the genetic diversity and structure of the current forest populations is essential for evaluating the ability to survive to future biotic and abiotic changes and planning conservation strategies. Quercus trojana is an eastern Mediterranean tree species with a fragmented distribution range, and its westernmost outposts are located in southern Italy. The demand for timber and cropland over the centuries has severely reduced it s occurrence in this part of the range. We assessed the genetic diversity and structure of the extant Italian populations of Q. trojana and derived conservation guidelines. A total of 322 samples were genotyped with six polymorphic nuclear microsatellite marker…
Polyamine Oxidase 5 loss-of-function mutations in Arabidopsis thaliana trigger metabolic and transcriptional reprogramming and promote salt stress to…
2017
The family of polyamine oxidases (PAO) in Arabidopsis (AtPAO1-5) mediates polyamine (PA) back-conversion, which reverses the PA biosynthetic pathway from spermine, and its structural isomer thermospermine (tSpm), into spermidine and then putrescine. Here, we have studied the involvement of PA back-conversion in Arabidopsis salinity tolerance. AtPAO5 is the Arabidopsis PAO gene member most transcriptionally induced by salt stress. Two independent loss-of-function mutants (atpao5-2 and atpao5-3) were found to exhibit constitutively higher tSpm levels, with associated increased salt tolerance. Using global transcriptional and metabolomic analyses, the underlying mechanisms were studied. Stimul…
Geometric analysis of intrusive growth of wood fibres in Robinia pseudoacacia
2018
ABSTRACT All cell types of the secondary xylem arise from the meristematic cells (initials) of the vascular cambium and grow under mechanical constraints emerging from the circular-symmetrical geometry that characterises many tree trunks. The course of intrusive growth of cambial initials has been elucidated, but is yet to be described in the case of xylem fibres. This study explains the geometry of intrusive growth of the secondary xylem fibres in the trunk of Robinia pseudoacacia. Long series of serial semi-thin sections of the vascular cambium and the differentiating secondary xylem were analysed. Since fibres grow in close vicinity to expanding cells of the derivatives of the vascular c…
A phytosociological analysis of the Olea europaea L. var. sylvestris (Mill.) Lehr. forests in Sicily
2019
This paper presents a phytosociological study on the forest vegetation of Olea europaea var. sylvestris of Sicily and of the smaller minor islands. In Sicily, Oleaster formations show considerable climacic potentiality in the bioclimactic belts between the infra- and the thermomediterranean with single edapho-climacic penetrations that are also in the mesomediterranean; however, these were largely destroyed by man in order to make room for crops. Furthermore, the residual expressions of the Oleaster forests are limited, and often exist as regenerated woodland made possible by the abandonment of agricultural land; they are often small forest nuclei–high maquis, woods and micro-woods–with a m…
Morphological and molecular variability within the fig cultivar 'Dottato' in the Italian protected designation origin area "fichi di Cosenza"
2017
The morphological and molecular diversity among fig accessions of 'Dottato', found in the PDO "Fichi di Cosenza" area was studied by evaluating 24 morphological traits and by genotyping with 18 microsatellite markers. The microsatellite allelic profiles among the putative clones of 'Dottato' indicated a moderate genetic variability, discriminating unambiguously most of the accessions. Only two groups of identity were found. The average expected and observed heterozygosity were 0.43 and 0.62, respectively. The mean polymorphic information content (PIC) was 0.4, varying from 0.08 (LMFC26) to 0.067 (FCUP 38-6). The morphological clustering allowed the distinction of all genotypes. Some genotyp…
Long-term effects of no tillage treatment on soil N availability, N uptake, and 15N-fertilizer recovery of durum wheat differ in relation to crop seq…
2016
Abstract No tillage (NT) soil management has largely been promoted because of its potential to generate both economic and environmental benefits. However, it often leads to reductions in crop yield and quality, which in many cases have been attributed to the effects this technique has on the nitrogen (N) dynamics in the soil–plant system. This 2-year study, performed within a long-term experiment in which NT was continuously applied for over 15 years, aimed to verify whether and to what extent the use of NT affects soil N availability, recovery of 15 N-labeled fertilizer, and N use efficiency (NUE) and its components (N uptake efficiency, NUpE; N utilization efficiency, NUtE). Durum wheat w…
Effects of species and soil-nitrogen availability on root system architecture traits - study on a set of weed and crop species
2017
Better managing crop : weed competition in cropping systems while reducing both nitrogen and herbicide inputs is a real challenge that requires a better understanding of crop and weed root architecture in relation to soil-nitrogen availability. An original approach was used which considered the parameters of a simulation model of root architecture as traits to analyse (a) the interspecific diversity of root system architecture, and (b) its response to soil-nitrogen availability. Two greenhouse experiments were conducted using three crop and nine weed species grown at two contrasted concentrations of soil-nitrogen availability. Plant traits were measured to characterise both overall plant gr…
Blackgrass (Alopecurus myosuroides Huds.) seed dispersal from a single plant and its consequences on weed infestation
2001
Blackgrass (Alopecurus myosuroides Huds.) seed dispersal from single mother-plants was studied in two experiments. For the first experiment, eight blackgrass plants of different heights and number of ears were produced in a greenhouse with the help of different in sowing densities and nitrogen nutrition levels. At the beginning of seed shedding, the plants were placed outside, and seeds were gathered daily. Daily seed dispersal was analysed by fitting a Weibull equation to the number of seeds as a function of distance to the mother-plant. The second experiment was carried out in a field comprising winter barley and spring barley plots as well as bare soil. In each of these three parts, two …
History of land-use intensity can modify the relationship between functional complexity of the soil fauna and soil ecosystem services - A microcosm s…
2012
Abstract Agricultural intensification generally results in the loss of soil organic matter, a decline in soil biodiversity, and the reduced ability of soils to retain nutrients. Intensified land-use can bring about legacy effects in soil ecosystem services that may last for hundreds of years after the cessation of agricultural practises. We studied, in a laboratory pot experiment, whether legacy effects due to intensive land/soil management (intensively managed wheat field) can be alleviated by restoring the disturbed soil with soil fauna typical of less managed soils (grassland soil). We also compared the effects of functional complexity of the soil fauna (microfauna, microfauna + mesofaun…
Variable impacts of enchytraeid worms and ectomycorrhizal fungi on plant growth in raw humus soil treated with wood ash
2007
Abstract An increasing amount of evidence shows the context dependent nature of various biotic interactions across terrestrial and aquatic ecosystems. We established a laboratory experiment to study whether the effects of Cognettia sphagnetorum (Enchytraeidae) and ectomycorrhizal fungi on Scots pine (Pinus sylvestris) seedling growth are influenced by wood ash application. Acidic coniferous forest soil was treated with wood ash at 5000 kg ha−1 or left as ash-free control and inoculated with soil saprotrophic microbes and nematodes. The microcosms were destructively sampled 26 and 51 weeks after initiation of the experiment. We measured enchytraeid and pine seedling biomass, abundance of nem…