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International audience; AbstractKey messageThe pine shoot beetle, Tomicus piniperda, is a potential vector of the pitch canker disease pathogen. The insect could transmit the pathogenic fungus during its maturation or regeneration feeding on the shoots of healthy pine crowns.ContextFusarium circinatum, the causal agent of pitch canker disease, currently affects Pinus radiata in northern Spain, causing pitch-soaked cankers and tree death. Although several species of the family Scolytinae have been reported as vectors of this pathogen, the role of the pine shoot beetle T. piniperda remains unclear.AimsThe general objective of this study was to determine whether T. piniperda is a vector for the pitch canker pathogen F. circinatum. For this purpose, Leach’s postulates (1) an association between T. piniperda and trees affected by pitch canker disease; (2) regular visits by T. piniperda to healthy P. radiata trees; (3) presence of the pathogen on the insect in nature; and (4) transmission of the pathogen to disease-free host material under controlled conditions.MethodsFresh green shoots with feeding galleries were collected from the ground, breeding galleries were collected from diseased trunks and insects were collected during their dispersion flights. A laboratory experiment was conducted in which specimens of T. piniperda were inoculated with the pathogen prior to feeding on shoots.ResultsIn the field, T. piniperda was found to be associated with both diseased and healthy P. radiata trees, and F. circinatum was found to be present, at low rates, on the exoskeleton of T. piniperda. In the laboratory experiment, evidence of the ability of T. piniperda to transfer the pathogen to healthy shoots was found.ConclusionsThe study findings indicate T. piniperda as a plausible vector of this pathogen. We postulate for the first time a potential relationship between the life cycles of T. piniperda and F. circinatum.

La necesidad de la conservacion fuera de areas protegidas ha llevado a la modificacion de las practicas productivas para permitir el mantenimiento de la biota silvestre en paisajes productivos tales como los asociados a la produccion de madera. Las plantaciones forestales podrian cooperar en la conservacion de la biodiversidad fuera de areas protegidas si tienen un sotobosque desarrollado. Sin embargo, el exito de los cambios en la produccion depende del apoyo social que estos reciben. Asi, evaluamos la preferencia por cinco paisajes con diferentes tipos de manejo forestal. Ademas, se evaluo la percepcion acerca de la relacion entre las plantaciones de pino y la fauna nativa a traves de encuestas realizadas en Chillan, Santiago y seis localidades rurales de la VII y VIII Region. Pese a no haber una opinion publica unanime respecto a considerar las plantaciones de pino como una amenaza a la biodiversidad, las personas en general prefieren las plantaciones de pino que sirven de habitat para la fauna en peligro de extincion. De hecho, estan de acuerdo en pagar mas por productos forestales que contribuyan a la conservacion en plantaciones forestales, prefiriendo especialmente plantaciones forestales con un sotobosque desarrollado. Estos resultados sugieren que las medidas destinadas a la conservacion en las plantaciones forestales podrian ser apoyadas por la sociedad chilena.

O trabalho teve como objetivo avaliar o potencial de clones de Eucalyptus urophylla para produção de painéis aglomerados homogêneos de baixa densidade. Foram avaliados seis clones de Eucalyptus urophylla com 94 meses de idade, plantados no municipio de Paracatu-MG, sendo utilizada como parâmetro de comparação a madeira de Pinus oocarpa. Para cada clone de Eucalyptus urophylla e também para o Pinus oocarpa foram produzidos seis painéis com o adesivo uréia-formaldeido no teor de 6%, densidade nominal de 0,60 g/cm³, pressão especifica de 40kgf/cm², temperatura de 160ºC e tempo de 8 minutos. Os clones de Eucalyptus urophylla apresentaram potencial para produção de painéis aglomerados convencionais de baixa densidade. Os clones 62 e 28 obtiveram os melhores resultados em todas as propriedades fisico-mecânicas avaliadas, apresentando propriedades iguais ou superiores as obtidas para os painéis produzidos com a madeira de Pinus oocarpa. Com relação à norma de comercialização CS 236/1966 apenas o clone 28 atendeu a todos os requisitos. Nenhum dos clones avaliados atendeu a norma EN 312/2003.

Investigations of local representations about the environment allow for the elucidation of historical landscape transformation and the elaboration of strategies for environmental conservation. Thus, this study aimed to answer the following questions. How does the local population represent the possible changes in riparian vegetation over time? What historical events were responsible for these possible changes? How does the local population represent concerns related to the use and maintenance of riparian vegetation? This study was carried out with 87 informants from three communities: two rural ex-settlement communities and one quilombo in Northeastern Brazil. According to the informants, there were changes in the riparian vegetation. The main causes of these changes include the type of agriculture practiced in the region and the building of a large dam to provide water to the city of Sobradinho in the state of Bahia. However, there was no significant difference between the number of informants who said that the changes were for the worse and those who said that they were for the better. In addition, the respondents reported an increase in the abundance of exotic species and a decrease in the abundance of native species. Thus, the importance of including this group of people in the process of the forest restoration that will occur in the region is emphasized because they possess information about the past vegetation changes and their causes. They can also indicate which species should be prioritized for replanting according to their usage needs and they understand the importance of conserving riparian vegetation.

In multifactor field experiments a close correlation is found between yield losses of two barley varieties (two-row Acha and six-row Sobolek) and air-dry biomass of weeds per unit area and proportion of their participation in total phytomass of the plant community in the crop tillering stage. The economic threshold of harmfulness 5% of the weed assemblage is calculated for both varieties. The possibility of weed control at a safe level by sowing the crop early is shown.

Analysing the effect water temperature has on Daphnia magna is essential in anticipating the impact climate change will have on this freshwater zooplanktonic keystone species. While many authors have followed this line of research, few have covered an extensive temperature range or complex temperature change scenarios. Global warming is mostly associated with increased extreme temperature events, such as heat waves, as well as earlier and more intense thermal stratification. Both of these events may directly influence D. magna fitness, especially in those populations performing diel vertical migration (DVM). We analysed the effect water temperatures, ranging from 11 to 29°C, have on the filtration capacity (FC) of D. magna, to anticipate the effects of acclimation, temperature change rate (TCR) and potential reversibility of responses to such conditions. Results show that sudden temperature changes have an immediate negative impact on the FC of D. magna and is more severe at higher temperatures and higher TCRs. However, D. magna individuals have shown themselves to be capable of quasi-acclimating to temperatures ranging from 11 to 25°C in around a week and achieving much higher FCs; albeit never reaching the optimal FC achieved at 20°C. That said, 29°C is lethal for D. magna individuals within approximately five days. Finally, non-optimal temperature acclimated individuals can recover maximal FC within 2–4 days of the optimal long-term acclimation temperature (20°C) being re-established, thus proving temperature responses to be reversible This work was supported by the University of Girona funding MPCUdG2016 and by the INNOQUA project from the European Union’s Horizon 2020 research and innovation program (Ares2016-1770486) to MFM, TS, and JC

Abstract The cod resources in the Barents Sea constitute the most important fisheries in Norway. In order to reduce resource allocation conflicts among different gear and vessel groups and to ensure profit for all participants throughout the value chain, the sector is thoroughly organized. The institutions established to ensure long-term sustainability, have been developed within the framework of a joint Norwegian–Russian fisheries management regime. However, due to a very high fishing mortality, the cod stock is now under severe pressure. In addition, a major part of the cod fisheries is highly seasonal and unable to be a stable supplier to neither the land-based industry nor demanding international markets. In parallel, cod farming is expected to become a new emerging industry, with potential to copy the success of farmed Atlantic salmon. Many actors within the cod fisheries fear the future competition from the growing cod farming sector. With reference to important attributes that characterize the cod fisheries and cod farming, this paper discusses how a future farming industry may affect the traditional cod fisheries. Moreover, we discuss how the fisheries may be forced to organize in the future to encounter the expected competition from cod farming.

Teak (Tectona grandis) has been widely planted in 70 tropical countries because of the utility and value of its wood. This species was introduced to Indonesia more than 100 years ago, and large plantations—covering 1.2 million ha—can be found on Java Island. However, little information currently exists about the genetic diversity and origin of these trees. We collected plant materials from three regions across Java Island (east, central, and west) and sampled trees spanning three age classes in each region, to clarify the genetic diversity and structure of teak plantations on Java Island. We investigated teak plantation and clonal experiment populations using multiplexed ISSR genotyping by sequencing (MIG-seq) and compared the genetic diversity and structure with the provenance test populations derived from natural teak forest in India, Myanmar, Thailand, and Laos. Analyses using 459 single-nucleotide polymorphism (SNP) loci revealed that native provenances had higher genetic diversity than the Indonesian teak plantations. Moreover, old teak plantations demonstrated lower genetic diversity than young plantations. Further analyses showed that most Indonesian teak plantations are genetically related to Laos, Thailand, and Myanmar provenances. We conclude that there is a weak genetic structure on teak plantations among the regions, which indicates that most plantations were established using plant materials from a specific part of the natural teak distribution. Information regarding the genetic diversity and structure of plantation forests should be taken into account when making future plantation programs.