Search results for "Pinus"
showing 10 items of 159 documents
Retrotranspozonu struktūra parastās priedes (Pinus sylvestris L.) genomā un to ekspresija
2014
ANOTĀCIJA Promocijas darbs izstrādāts Latvijas Valsts mežzinātnes institūtā „Silava”. Pētījuma mērķis bija identificēt aktīvos retrotranspozonus parastās priedes (Pinus sylvestris L.) genomā un raksturot to transkripcijas līmeni dažādu stresa veidu ietekmē kontrolētos apstākļos. Pētījumā izmantoti nespecifiskie retrotranspozonu marķieri balstīti uz augsti konservatīvām tRNS piesaistes vietām. Viena klona priežu rametus pakļāva dabā izplatītam karstuma stresam, kukaiņu invāzijai (priežu hermess (Pineus pini L.), kā arī mākslīgi izraisītai augu hormonu (abscīzskābes un salicilskābes) ietekmei. Darba rezultātā identificēti pārsvarā I klases mobīlo elementu pārstāvji, kā arī tos saturošie himēr…
Nest modifications by the acorn ant Temnothorax crassispinus (Hymenoptera: Formicidae)
2019
Many ant species construct nests and during the process considerably influence the environment such as by changing soil structure and creating new habitat for other species. However, other ant species dwell in ready-for-use cavities. Ants of the genus Temnothorax inhabit small cavities such as acorns and under rocks, but under natural conditions, good nest sites are limited resources. During field and laboratory experiments, I studied how the acorn ant Temnothorax crassispinus (Karawajew, 1926) modifies nesting sites. Temnothorax crassispinus is a forest species, which typically lives in cavities in fallen twigs and acorns; colonies usually number from a few dozen to about 200 workers. Alth…
Changes in the free amino acids and the biogenic amine contents during lactic acid fermentation of different lupin species
2016
Summary The aim of the work was to evaluate the profile of free amino acids (FAA) as the possible precursors of biogenic amines (BAs) in different varieties and hybrid lines of Lupinus luteus and Lupinus angustifolius and its changes during fermentation. Lupins have high amounts of FAA, and therefore, significant contents of BAs by the action of bacterial amino acid decarboxylases can be formed. In view of this, the effect of three Pediococcus pentosaceus strains KTU05-8, KTU05-9 and KTU05-10 on BA formation during lupin fermentation was studied. The formation of BAs was monitored during 48-h fermentation at solid-state conditions and compared with that in samples after submerged fermentati…
Produzione e utilizzazione delle biomasse dei rimboschimenti in Sicilia
2007
Per recepire l’orientamento di fondo dei principi di Kyoto e le seguenti azioni, e necessario verificare le fonti energetiche alternative, e tra queste ha rilevanza la biomassa forestale. L’utilizzo di questa e legato tuttavia alla disponibilita sul territorio e alla sua dispersione. Il lavoro presentato analizza le principali fonti di biomasse presenti sull’isola, la loro dispersione e entita di prelievo sostenibile, ipotizza la possibilita di recupero a fini energetici del materiale di scarsa qualita prodotto in impianti di arboricoltura da legno. Infine viene analizzato il contributo possibile degli impianti di eucalitto diffusamente presenti su parte del territorio siciliano, anche nell…
Adaptive radiation along a thermal gradient: preliminary results of habitat use and respiration rate divergence among whitefish morphs.
2014
Adaptive radiation is considered an important mechanism for the development of new species, but very little is known about the role of thermal adaptation during this process. Such adaptation should be especially important in poikilothermic animals that are often subjected to pronounced seasonal temperature variation that directly affects metabolic function. We conducted a preliminary study of individual lifetime thermal habitat use and respiration rates of four whitefish (Coregonus lavaretus (L.)) morphs (two pelagic, one littoral and one profundal) using stable carbon and oxygen isotope values of otolith carbonate. These morphs, two of which utilized pelagic habitats, one littoral and one …
Effect of lactic acid fermentation of lupine wholemeal on acrylamide content and quality characteristics of wheat-lupine bread
2013
The effect of supplementing wheat flour at a level of 15% with lupine (Lupinus angustifolius L.) wholemeal fermented by different lactic acid bacteria on acrylamide content in bread crumb as well as on bread texture and sensory characteristics was analysed. The use of fermented lupine resulted in a lower specific volume and crumb porosity of bread on an average by 14.1% and 10.5%, respectively, while untreated lupine lowered the latter parameters at a higher level (30.8% and 20.7%, respectively). The addition of lupine resulted in a higher by 43.3% acrylamide content compared to wheat bread (19.4 µg/kg dry weight (d.w.)). Results showed that acrylamide was significantly reduced using proteo…
Lake size and fish diversity determine resource use and trophic position of a top predator in high-latitude lakes
2015
Prey preference of top predators and energy flow across habitat boundaries are of fundamental importance for structure and function of aquatic and terrestrial ecosystems, as they may have strong effects on production, species diversity, and food-web stability. In lakes, littoral and pelagic food-web compartments are typically coupled and controlled by generalist fish top predators. However, the extent and determinants of such coupling remains a topical area of ecological research and is largely unknown in oligotrophic high-latitude lakes. We analyzed food-web structure and resource use by a generalist top predator, the Arctic charr Salvelinus alpinus (L.), in 17 oligotrophic subarctic lakes…
Nutrient Assimilation by First-Feeding African Catfish, Clarias gariepinus , Assessed Using Stable Isotope Analysis
2013
Knowledge of ingredients assimilation and biomass contribution to recipient fish is important in feed formulation. The stable isotopes of 13C and 15N were used to investigate the assimilation and biomass contribution of bambaranut, Voandzeia subterranea, meal (BNM), corn, Zea mays, meal (CM) and fish meal (FM), in FM substituted diets of first feeding African catfish, Clarias gariepinus, during a 30-d experiment. The catfish larvae were stocked at 40 fish/15 L three replicate glass aquaria. Larvae were fed with experimental diets varying FM, BNM, and CM. Proportions of FM : BNM : CM in the experimental diets were: feed 1 (F1) 60:20:20; feed 2 (F2) 40:40:20; feed 3 (F3) 20:60:20; and feed 4 …
Induction of radiata pine somatic embryogenesis at high temperatures provokes a long-term decrease in dna methylation/hydroxymethylation and differen…
2020
Based on the hypothesis that embryo development is a crucial stage for the formation of stable epigenetic marks that could modulate the behaviour of the resulting plants, in this study, radiata pine somatic embryogenesis was induced at high temperatures (23 °
Introduction of Mysis relicta (Mysida) reduces niche segregation between deep-water Arctic charr morphs
2019
This is a post-peer-review, pre-copyedit version of an article published in Hydrobiologia. The final authenticated version is available online at https://doi.org/10.1007/s10750-019-3953-4. Niche diversification of polymorphic Arctic charr can be altered by multiple anthropogenic stressors. The opossum-shrimp (Mysis relicta) was introduced to compensate for reduced food resources for fish following hydropower operations in Lake Limingen, central Norway. Based on habitat use, stomach contents, stable isotopes (δ13C, δ15N) and trophically transmitted parasites, the zooplanktivorous upper water-column dwelling ‘normal’ morph was clearly trophically separated from two sympatric deep-water morphs…