scholarly journals Alnus glutinosa Threatened by Alder Phytophthora: A Histological Study of Roots

Pathogens ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 977
Author(s):  
Corina Nave ◽  
Juliette Schwan ◽  
Sabine Werres ◽  
Janett Riebesehl
Keyword(s):  
Species Complex ◽  
Parental Species ◽  
Histological Study ◽  
Alnus Glutinosa ◽  
Phytophthora Species ◽  
Artificial Infection ◽  
Histological Studies ◽  
Black Alder ◽  
The Subject ◽  
Different Parts

Alder dieback remains a major problem in European alder stands and its spread continues to threaten their existence. The causal agent of this disease is the so-called alder Phytophthora species complex, which includes the hybrid Phytophthora ×alni and its parental species P. uniformis and P. ×multiformis. Little is known about the survival of these Phytophthora species in alder. The aim of our investigations was to find out whether, and if so where, the pathogen survives. The subject of these studies was alder roots. Therefore, artificial infection studies and histological studies with P. ×alni and P. uniformis were carried out on seedlings of black alder (Alnus glutinosa). These histological studies revealed oogonia and oospores of P. ×alni and P. uniformis in different parts of the root tissue.

The Mystery of Freedom

2020 ◽  
pp. 192-206
Author(s):  
Pilar López de Santa María
Keyword(s):  
The State ◽  
Theory Of Knowledge ◽  
The Will ◽  
The Subject ◽  
Different Parts

Freedom is the focus of the first of the writings included in The Two Fundamental Problems of Ethics. The attention that Schopenhauer devotes to the subject does not stop here, however, since freedom appears recurrently in different parts of his system. It is linked to his theory of knowledge, metaphysics, aesthetics, and the denial of the will. This chapter follows that track and examines the presence in different contexts of Schopenhauerian thought of a freedom that is so undeniable as unexplainable. In this way will be shown Schopenhauer’s transition from the freedom of the voluntas to the freedom of noluntas [non-willing] and the state of great liberation that occurs because the will frees itself from itself. It is a transition that begins and ends at the same point: mystery

scholarly journals Glossiness Evaluation of Coated Wood Surfaces as Function of Varnish Type and Exposure to Different Conditions

Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 558
Author(s):  
Emilia-Adela Salca ◽  
Tomasz Krystofiak ◽  
Barbara Lis ◽  
Salim Hiziroglu
Keyword(s):  
Artificial Aging ◽  
Chemical Resistance ◽  
Heat Exposure ◽  
Value Added ◽  
Alnus Glutinosa ◽  
Practical Applications ◽  
Black Alder ◽  
Structural Differences ◽  
Wood Surfaces ◽  
Water Borne

The objective of this study was to evaluate the glossiness of black alder wood (Alnus glutinosa L.) samples coated with two varnish types as a function of exposure to dry heat and artificial aging. The chemical resistance of the coated samples to cold liquids was also evaluated. Based on the findings in this work, it appears that the varnish types and their structural differences influenced the overall glossiness of the coated samples. The UV varnish exhibited higher gloss values than those coated with the water-borne product within the range of silky gloss and silky matte grades. The heat exposure influenced the surface glossiness of the UV-coated samples more than the samples coated with water-borne varnish. The overall gloss values of the samples decreased with the exposure time to artificial aging, resulting in no layer cracks. The cold household liquids left less visible traces on the surfaces and alcohol was found to be the strongest agent. This study could have practical applications in the furniture industry to produce value-added furniture units according to their specific conditions of indoor use.

scholarly journals Response of black alder (Alnus glutinosa (L.) Gaertn.) to selective thinning of various intensities

2020 ◽  
Vol 144 (7-8) ◽  
pp. 378-378
Author(s):  
Simon Lendvai ◽  
Jurij Diaci ◽  
Dušan Roženbergar
Keyword(s):  
Alnus Glutinosa ◽  
Black Alder

Područje poplavnih šuma crne johe (Alnus glutinosa (L.) Gaertn.) u Sloveniji čini samo 0,4 % (približno 4708 ha) ukupne površine šumskog zemljišta (Čater i sur., 2001.). Veći kompleks takvih sastojina u Sloveniji su Črni i Polanski Log, a istraživanje je provedeno na području potonjeg (slika 1). Kako čiste sastojine johe odlikuju brojne specifičnosti, potrebno im je prilagoditi šumskouzgojne postupke. Da bi se utvrdio odgovarajući intenzitet prorjede takvih sastojina, 1967. godine u Polanskom Logu postavljene su pokusne plohe. Od tada do 2018. godine na plohama je izvršeno pet do sedam mjerenja. Sva stabla na plohama su bila obrojčana. Izvršeno je mjerenje prsnih promjera i procjena sljedećih elemenata na stablima: pripadnost etaži, vitalnost, uzgojna perspektiva, uzgojna uloga, duljina krošnje i kvaliteta (tablica 3). Svaka ploha bila je podijeljena u tri polja (40 x 50 m) s različitim metodama rada: bez intervencije, umjereno i intenzivno prorjeđivanje. Uzgojni postupci koji su poduzeti tijekom praćenja pokusa prikazani su u tablici 2. Danas su te sastojine u zreloj fazi razvoja, stoga smo u ovom radu analizirali reakcije crne johe na različite intenzitete prorjeđivanja i dobivene rezultate usporedili s preporukama autora tradicionalnih uzgojnih modela i modela koji se temelje na situacijskoj njezi šuma. Ustanovili smo da se na plohama s intenzivnim prorjeđivanjem gustoća sastojine koja je u dobi između 50 i 70 godina i na kraju je ophodnje kreće od 295 do 690 kom/ha (slika 3), dok se na plohama bez intervencije ova vrijednost kreće u rasponu od 370 do 790 kom/ha. Drvne zalihe u istom su se razdoblju kretale u rasponu od 277 do 458 m<sup>3</sup>/ha na plohama s intenzivnim prorjeđivanjem, dok su na plohama bez intervencije bile veće, u rasponu od 309 do 516 m<sup>3</sup>/ha (slika 4). U to su se doba temeljnice nalazile u rasponu između 23 i 41 m<sup>2</sup>/ha na plohama s intenzivnim prorjeđivanjem, a na plohama bez intervencije u rasponu od 26 do čak 51 m<sup>2</sup>/ha (slika 5). Tijekom cijelog razdoblja praćenja ploha, stabla su, bez obzira na metodu rada, narasla za tri do četiri debljinska stupnja (slika 2). Na plohama s umjerenim prorjeđivanjem i onima bez intervencije, debljinski prirast stabala bio je skoro jednak (0,33 cm godišnje) (slika 6). Statistički je značajan veći debljinski prirast stabala na plohama s jako intenzivnim prorjeđivanjem (0,37 cm godišnje). Debljinski prirast dominantnih stabala bio je nešto veći, od 0,46 cm godišnje na plohama bez intervencije do 0,50 cm godišnje na plohama s jako intenzivnim prorjeđivanjem, ali statistički značajne razlike između metoda rada nisu utvrđene (slika 6). Međutim, otkrili smo da kod dominantnih stabala ne postoje statistički značajne razlike s obzirom na njihovu slojevitost, vitalnost, tendenciju, dužinu krošnje i kvalitete s obzirom na korištenu metodu rada. U usporedbi s uzgojnim modelima koji su se koristili za manji broj odabranih stabla, gustoća i temeljnica ispitivanih sastojina je znatno veća, a debljinski prirast manji. Autori tradicionalnih i modela s manjim brojem odabranih stabala zagovaraju rano prorjeđivanje takvih sastojina (tablica 1). Veće razlike nastaju u konačnom broju stabala po hektaru i u intenzitetu intervencije. Razlog malog debljinskog prirasta i razlike između metoda rada na našim plohama pripisali smo nedovoljnom intenzitetu i djelomično nedosljednoj provedbi postupka prorjeđivanja. Ipak, ukazala se potreba za intenzivnim prorjeđivanjem i pospješivanjem rasta stabala najvećeg prsnog promjera, vitalnosti i tendencije, lijepo oblikovane i duge krošnje (slika 7, slika 8).

scholarly journals Effects of botanical antifeedants on Melolontha melolontha grub feeding on Scots pine roots

2014 ◽  
Vol 56 (3) ◽  
pp. 135-140 ◽  
Author(s):  
Iwona Skrzecz ◽  
Alicja Sowińska ◽  
Wojciech Janiszewski
Keyword(s):  
Pinus Sylvestris ◽  
Scots Pine ◽  
Pure Water ◽  
Alnus Glutinosa ◽  
Open Area ◽  
Antifeedant Activity ◽  
Tree Roots ◽  
Black Alder ◽  
Melolontha Melolontha ◽  
Extent Of Damage

Abstract The aim of the study was to evaluate the possibility of using botanic antifeedants to reduce the damage caused by Melolontha spp. grubs. To achieve the objective, the experiments were established in semi-field conditions to estimate the antifeedant activity of rutin, quercetin (flavonoids from buckwheat Fagopyrum esculentum) and an extract from black alder Alnus glutinosa leaves against Melolontha melolontha grubs. The grubs were placed individually in the pots with a soil in which 2 year old Pinus sylvestris trees were planted. The pots were put in garden pavilions placed in the open area. Then the soil in the pots were watered with the emulsions of rutin, quercetin, an extract from A. glutinosa leaves, and with pure water-comparative variant. After 4 months, the weight and mortality of grubs were compared, as well as the weight of tree roots in all pots. There was no effect of the antifeedants on the development and extent of damage caused by M. melolontha grubs. The results do not indicate the use of botanic antifeedants in the protection of forests against the cockchafer grubs

scholarly journals Indigenous views on the future of public archaeology in Australia

2021 ◽  
Vol 10 ◽  
pp. 31
Author(s):  
Kellie Pollard ◽  
Claire Smith ◽  
Jasmine Willika ◽  
Vince Copley sr ◽  
Vincent Copley jr ◽  
...  
Keyword(s):  
Real Life ◽  
Public Archaeology ◽  
Free Form ◽  
Online Journal ◽  
High Profile ◽  
The Future ◽  
The Subject ◽  
Final Text ◽  
Different Parts ◽  
School Curricula

This paper was written in response to a request by the editors of the AP: Online Journal of Public Archaeology, Jaime Almansa Sánchez and Elena Papagiannopoulou, for Claire Smith to write on the future of public archaeology in Australia. In Australia, public archaeology focusses on high profile colonial sites such as The Rocks in Sydney (Karskens 1999) and Port Arthur in Tasmania (Steele et al. 2007; Frew 2012), tourism (e.g. Cole and Wallis 2019) or enhancing school curricula (Nichols et al. 2005; Owens and Steele 2005). However, given her decades-long relationships with Jawoyn and Ngadjuri people (Smith 1999; Smith et al. 2016; Smith et al. 2020), Claire Smith decided that a useful way of approaching this topic would be to obtain Indigenous views on the subject. Accordingly, she contacted the Aboriginal co-authors of this article and invited them to co-author the paper. The possibility to write in free form was a boon. The ‘conversation’ format we settled on was designed to facilitate the voices of individuals, to present a range of Indigenous views, to allow people to express their views frankly, and to deal with the constraints of people being located in different parts of Australia as well as occasional lock-downs due to COVID-19. We decided on five topics/questions that would be the basis of the conversation. Each Aboriginal author gave their views either by email or by phone. These views were interwoven into a ‘conversation’. The language has been edited lightly for clarity and to simulate a real-life conversation. The final text was approved by all authors.

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