A case study of <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> fingerprinting for breeding

• Introduction  

Tree genetic improvement programs usually lack, in general, pedigree information. Since molecular markers can be used to estimate the level of genetic similarity between individuals, we genotyped a sample of a Portuguese Eucalyptus globulus breeding population—a reference population of 125 individuals—with 16 microsatellites (SSR).     

Relating genetic variation of ecologically important tree traits to associated organisms in full-sib aspen families

Knowledge on phenological, morphometric, and phytochemical variation of local progenies of European aspen (Populus tremula, L.) is limited. The goal of this study was to characterize variation in growth and ecologically important leaf properties in aspen full-sib families in relation to interacting organisms (mycorrhiza, endophytes, and insects) and to determine whether these interactions were affected by soil application of a systemic fungicide. In local progenies, within-family variation of neutral molecular genetic markers (nuclear microsatellites) was higher than between families. Significant variation in growth, production of phenolic defensive compounds and other phytochemical leaf traits was found between families. Phenolic compounds showed clear negative correlation with generalist herbivores, but did not result in negative trade-off with biomass production. Differences in mycorrhizal colonization were not found among full-sib families and application of a systemic fungicide suppressed neither mycorrhizal colonization nor infestation with insects. However, a strong suppression of endophytes occurred, whose long-term consequences may require attention when fungicides are used in agroforestry plantations.     

Development of an air-injection press for preventing blowout of particleboard II: improvement of board properties using small-diameter holes for air injection

An air-injection press, which has holes punched in the heating plates, injects high-pressure air through the holes of one plate into boards during press heating. The air-injection press can manufacture boards from high-moisture-content particles by controlling blowouts of the boards. In this study, boards were manufactured from particles that had a moisture content of 25% by using the air-injection press, which reduced the required pressing time. Boards manufactured by injecting air through holes of 5 mm in diameter were of poor quality with a low internal bond strength of only 0.31 MPa. When the hole diameter was reduced to 1 mm, the internal bond strength increased to 0.44 MPa. A high air-injection pressure of 0.55 MPa also resulted in improved board properties over those for boards manufactured at lower pressures. This was probably because a large amount of binder was released from boards through the 5-mm holes, together with water vapor, during air injection; the small-diameter holes reduced the release of binder, resulting in better board properties.     

Grouping of <Emphasis Type="Italic">Tectona grandis</Emphasis> (L.f.) clones using wood color and stiffness

Commercial Tectona grandis plantations using clones have attracted considerable interest for lumber production in tropical regions where small areas are frequent. However, studies on wood properties are limited. Therefore, the purpose of this study is to group clones with similar wood color characteristics using the CIELab system, and mechanical resistance by dynamic stiffness (Ed) in order to obtain different types of clones for different climate and edaphic conditions. It was found that lightness (L*), yellowness (b*), redness (a*), and Ed are similar to those found for other plantation trees. These wood characteristics are significantly influenced by clone and site. Variance due to clone and site went from 31 to 53% and from 2.95 to 24.22%, respectively. Another source of variance was distance from pith, with the exception of parameter b*, which was not affected. Finally, clones were grouped (using multivariate analysis) according to color and mechanical resistance. This analysis established 4 groups by color and 5 groups by Ed. Clone clustering will allow us to choose or use clones with similar wood properties according to site and environmental conditions increasing area production and wood quality uniformity.     

A landscape and policy perspective on forest conversion: Long-tailed tit (<Emphasis Type="Italic">Aegithalos caudatus</Emphasis>) and the allocation of deciduous forests in southern Sweden

As resources allocated specifically for conservation are limited, there is a need to ensure conservation policy initiatives lead to effective conservation outcomes. In this study, we investigated the potential conservation benefits from alternative spatial allocations of old deciduous stands to a landscape dominated by coniferous production forests owned primarily by non-industrial private forest owners. As a target species, we used the long-tailed tit (Aegithalos caudatus), a species associated with deciduous forests and known to be sensitive to isolation. We used a previously published model based on empirical data on the occurrence of this species, to assess the probability of occurrence of the bird in a 4,000 km² area in southern Sweden for which we possess detailed spatial GIS data (kNN data) of tree species composition and age. We assessed alternative scenarios where old deciduous forest was allocated with or without respect to distance from existing old deciduous forests. Due to the long-tailed tit’s habitat requirement increasing the amount of old deciduous forests close to existing habitats was the most effective strategy. However, the potential advantages of this strategy may in fact be overturned in favor of the other scenarios if ownership structures and probable uptake rates of policy initiatives are also considered. If a policy initiative is targeted toward owners with properties in close proximity to existing suitable habitat, when compared to if all forest owners are targeted, a higher proportion of owners is needed to participate in order to achieve the same degree of habitat creation for the species. Here, we discuss the potential benefits for effective conservation policy formulation from integrating spatially explicit datasets and detailed ecological knowledge with land-ownership structures and policy uptake scenarios.     

Canopy structure analysis for estimating forest regeneration dynamics and growth in <Emphasis Type="Italic">Nothofagus pumilio</Emphasis> forests

•Introduction   

Silviculture systems applied in Nothofagus pumilio forests are based on opening the canopy to stimulate natural regeneration by modifying light and soil moisture. The objective is to evaluate regeneration dynamics of N. pumilio along different forest canopy and solar radiation gradients.     

Effects of chlorantraniliprole on development and reproduction of beet armyworm, <Emphasis Type="Italic">Spodoptera exigua</Emphasis> (Hübner)

The lethal and sublethal effects of chlorantraniliprole against Spodoptera exigua (Hübner) were evaluated under laboratory conditions by oral exposure of neonate larvae to the compound. The 72 h LC₅₀ value of this insecticide to S. exigua was found to be 12.747 μg l⁻¹. A progressive larval mortality of 24.32% for LC₃₀ treatment and 42.61% for LC₅₀ treatment was observed from 4th to 6th day after exposure, which resulted in the reduced pupation rates in exposure groups. The sublethal effects of this chemical were indicated by prolongation of larval period, the increase of pupal weight and decrease in hatch rate of egg. Chlorantraniliprole at LC₃₀ and LC₅₀ rate significantly delayed larval development; the developmental duration of surviving larvae was extended for 22.5 and 28.6%, respectively, compared with that of control group. LC₃₀ treatment increased the mean weight of pupa and induced to the production of heavier pupa (>150 mg). In LC₅₀ treatment, heavier pupa also showed up but the mean weight of pupa was not influenced. The egg hatch rate in LC₅₀ group was significant lower than that in control and LC₃₀ groups. No significant differences in pupal duration, emergence rate, sex ratio, egg number per female, and longevity of adults were observed among treatments. Chlorantraniliprole had exceptional activity against S. exigua according to concentration–response bioassay in laboratory, and the toxicities were primarily resulted from immediate lethality.     

Ectomycorrhizal communities in a Mediterranean forest ecosystem dominated by <Emphasis Type="Italic">Quercus ilex</Emphasis>: seasonal dynamics and response to drought in the surface organic horizon

• Introduction   

Millions of hectares of Quercus ilex forests dominate disturbed landscapes in the western part of the Mediterranean basin. Although these forests are very widespread, little is known about the composition and structure of their associated ectomycorrhizal fungal communities.     

The toxicity of selected acaricides against five stored product mites under laboratory assay

In laboratory tests, the toxicity of acaricides targeted against house dust mites was tested on five species of stored product mites (Acarus siro, Aleuroglyphus ovatus, Carpoglyphus lactis, Lepidoglyphus destructor, and Tyroborus lini). The formulations of benzyl-benzoate, benzyl-benzoate/permethrin/pyriproxyfen, and neem were diluted in water and applied to filter paper in an unventilated chamber. The mortality of mites was observed after 24 h of exposure to acaricide-impregnated filter paper. All of the tested acaricides were toxic to all of the mite species. There were significant differences in mortality among the species and the acaricides. Benzyl-benzoate/permethrin/pyriproxyfen was the most effective, followed by benzyl-benzoate and neem. L. destructor (LD₅₀ 0.01–0.11 μg) was the most sensitive mite species, followed by A. siro (LD₅₀ 0.04–0.12 μg), T. lini (LD₅₀ 2–21 μg), A. ovatus (LD₅₀ 3–18 μg), and C. lactis (LD₅₀ 4–64 μg). Based on the highly toxic effects of the tested acaricides against the stored product mites, the acaricides should be considered as a potential tool in the control of stored product mites, although next screening is necessary.     

Allocation of varietal testing efforts for implementing conifer multi-varietal forestry using white spruce as a model species

• Introduction   

Multi-varietal forestry (MVF) is the deployment of tested tree varieties in plantation forestry. Computer simulation using POPSIM Simulator identified optimal combination of numbers of families, varieties per family and ramets per variety (nf, nc and nr, respectively) yielding the largest genetic gain for a specific status number (NS) in a varietal test (VT) intended for MVF of conifers.