scholarly journals Development and Characterisation of Irap Markers From Expressed Retrotransposon-like sequences in Pinus sylvestris L.

Author(s):  
Angelika Voronova ◽  
Dainis Ruņģis

AbstractConifer genomes are large and stably diploid, in contrast to angiosperms, which are more variable both in genome size and ploidy. Conifer genomes are characterised by multiple gene families and pseudogenes, contain large inter-gene regions and a considerable proportion of repetitive sequences. All members of plant retrotransposon orders have been identified in gymnosperm genomes, however active elements have not been described. Investigation of transposable elements in Scots pine (Pinus sylvestris L.) could offer insights into transposon-mediated reorganisation under stress conditions in complex and ancient plant genomes. Nine Pinus sylvestris specific markers were developed to hypothetical long terminal repeats (LTRs) from differentially expressed retrotransposon-like fragments after heat stress and insect damage. Genetic diversity of 150 trees from a naturally regenerated pine stand was investigated using the IRAP method. The developed markers revealed high levels of genetic diversity and were able to distinguish subpopulations growing in long-term differential environmental conditions. Somaclonal variation was also investigated using these markers and polymorphic fragments were identified between ramets of Scots pine clones growing in two different plantations, possibly indicating evidence of recent transposition events. Sequencing of the polymorphic fragments identified two groups of sequences containing LTR sequences of an unknown retrotransposon with homology to the LTRs of the Copia-17-PAb-I element.

The Holocene ◽  
2021 ◽  
pp. 095968362199465
Author(s):  
Dael Sassoon ◽  
William J Fletcher ◽  
Alastair Hotchkiss ◽  
Fern Owen ◽  
Liting Feng

Around 4000 cal yr BP, Scots pine ( Pinus sylvestris) suffered a widespread demise across the British Isles. This paper presents new information about P. sylvestris populations found in the Welsh Marches (western central Britain), for which the long-term history and origins are poorly known. Two new pollen records were produced from the Lin Can Moss ombrotrophic bog (LM18) and the Breidden Hill pond (BH18). The LM18 peat core is supported by loss-on-ignition, humification analysis and radiocarbon dating. Lead concentrations were used to provide an estimated timeframe for the recent BH18 record. In contrast to many other Holocene pollen records from the British Isles, analysis of LM18 reveals that Scots pine grains were deposited continuously between c. 6900–300 cal yr BP, at frequencies of 0.3–5.4%. It is possible that individual Scots pine trees persisted through the wider demise on thin soils of steep drought-prone crags of hills or the fringes of lowland bogs in the Welsh Marches. At BH18, the record indicates a transition from broadleaved to mixed woodland, including conifer species introduced around AD 1850 including Picea and Pinus. The insights from BH18 suggest that the current populations may largely be the result of planting. Comparison of the LM18 findings with other regional pollen records highlights consistent patterns, including a Mid-Holocene maximum (ca. 7000 cal yr BP), long-term persistence at low pollen percentages and a Late-Holocene minimum (ca. 3000 cal yr BP). These distinctive trends encourage further studies on refugial areas for Scots pine in this region and elsewhere.


Silva Fennica ◽  
2021 ◽  
Vol 55 (5) ◽  
Author(s):  
Markus Melin ◽  
Tiina Ylioja ◽  
Leena Aarnio ◽  
Katri Hamunen ◽  
Seppo Nevalainen ◽  
...  

Bark beetles are amongst the most aggressive pest agents of coniferous forests. Due to this, many boreal countries have designated laws aiming to lower the risk of bark beetle epidemics. Finland’s forest legislation has pre-emptive measures targeted against bark beetles, and for Scots pine ( L.), the law concerns pine shoot beetles ( spp.). This study used data collected around 25 piles of Scots pine roundwood that were harvested in the winter but left in the forest until the following November. Thus, the pine shoot beetles were able to use the piles for breeding. We assessed the number of emerged insects from the piles and the cascading damage they caused in the surrounding forests. All roundwood piles, regardless of their volume, were used by the beetles for breeding. Highest densities of beetle exit holes were found from the parts of the log with thick and intact bark. If the bark of the log was damaged by the harvester head, the number of beetles decreased significantly. Depending on the volume of the roundwood pile, the cascading damage (fallen shoots) was noticeable up to ca. 40–60 m from the roundwood pile. Storing of piles smaller than 50 m did not cause excess damage. The number of fallen shoots per tree was generally below the known thresholds for when growth losses can occur. However, the study was conducted in mature forests, and it can be assumed that the recorded damage levels would severely affect the growth of young pines, raising the question of where to store the roundwood. As with other bark beetles, the role of beetles as damage agents may change in the future, but based on this as well as past studies, the species can be viewed as a notable damage agents only around long-term wood storage sites in the current northern conditions.Pinus sylvestrisTomicus3Tomicus


Author(s):  
Vida Stravinskienė ◽  
Regina Erlickytė-Marčiukaitienė

Investigation of Scots pine annual radial increment was carried out in the surroundings of one of the largest pollution sources in Lithuania – the cement plant “Akmenes cementas”. The main objective of the investigation was to analyse possible impact of climatic and anthropogenic factors on the radial growth of Scots pine (Pinus sylvestris L.) stands growing in the local impact zone of the plant. Investigation has shown that in peat‐bog sites active vegetation period temperature higher than the long‐term average influences the formation of radial increment positively (r = 0.22–0.34; p < 0.05), and July precipitation higher than the long‐term average causes the reduction of radial increment (r = ‐0.25; p < 0.05) of the investigated pines. Analysis of the relation between pine radial increment and plant emissions has shown that the strongest correlations are in the closest vicinity of the plant (r = -0.63; p < 0.05). Weaker, but statistically significant relations were found between radial increment of pines growing at a distance of 5–10 km from the plant and plant emissions (r = -0.49; p < 0.05), and for the most distant pine correlations became insignificant (p > 0.05). Linear regression results have shown that changes of the radial increment of pine stands closest to the plant are the biggest and they decrease with distance from the plant. Santrauka Paprastosios pušies (Pinus sylvestris L.) metinio radialiojo prieaugio pokyčių tyrimai buvo atliekami cemento gamyklos „Akmenės cementas“ aplinkoje. Pagrindinis šio tyrimo tikslas – nustatyti galimą klimato ir antropogeninių veiksnių įtaką paprastosios pušies (Pinus sylvestris L.) medynų radialiajam prieaugiui gamyklos aplinkoje. Nustatyta, kad gamyklos aplinkoje augančiuose raistašilio (Carico–sphagnosa) miško tipo pušynuose teigiamos įtakos pušų radialiojo prieaugio formavimuisi turi aukštesnė nei vidutinė daugiametė aktyviosios vegetacijos oro temperatūra (r = 0,22–0,34; p < 0,05), o didesnis nei vidutinis daugiametis liepos mėnesio kritulių kiekis lemia radialiojo prieaugio mažėjimą (r = –0,25; p < 0,05). Nagrinėjant pušų radialiojo prieaugio sąsają su gamyklos teršalų kiekiu, stipriausias koreliacinis priklausomumas nustatytas artimiausioje gamyklos aplinkoje (iki 5 km) (r = –0,63; p < 0,05). Silpnesnis, tačiau statistiškai patikimas priklausomumas nustatytas tarp vidutiniu atstumu nuo gamyklos (5–10 km) augančių pušų prieaugio ir gamyklos teršalų kiekio. Toliausiai nuo gamyklos (per 10–20 km) augančių pušų radialiojo prieaugio sąsaja su bendruoju ir pavienių teršalų kiekiu yra statistiškai nepatikima (p > 0,05). Iš tiesinės regresinės analizės rezultatų akivaizdu, kad pušynų artimiausioje gamyklos aplinkoje metinio radialiojo prieaugio pokyčiai yra didžiausi, o tolstant nuo gamyklos mažėja. Резюме Исследования годового радиального прироста сосны обыкновенной (Pinus sylvestris L.) были проведены в окрестностях цементного завода „Акмянес цементас“. Главная цель исследования – определить возможное влияние климатических и антропогенных факторов на изменение радиального прироста сосны обыкновенной (Pinus sylvestris L.), произрастающей в окрестностях цементного завода. Исследования показали, что на формирование радиального прироста сосен, растущих в сосновых древостоях леса типа Carico-sphagnosa, позитивное влияние оказывает температура воздуха, превышающая среднюю многолетнюю температуру воздуха активной вегетации (r = 0.22–0.34; p < 0.05), а количество осадков в июле, превышающее среднее многолетнее количество, способствует уменьшению радиального прироста (r = –0.25; p < 0.05). Корреляционный анализ зависимости радиального прироста сосен от эмиссии завода показал сильнейшую связь (r = –0.63; p < 0.05) на расстоянии до 5 км от завода. На расстоянии 5–10 км от завода корреляционная связь уменьшается, а при дальнейшем удалении от завода статистически не доказана. Результаты линейной регрессии показали, что наибольшие изменения радиального прироста сосен происходят на расстоянии до 5 км от завода, а с увеличением расстояния от завода они уменьшаются.


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