Project description:A high-throughput quantitative Nuclear Magnetic Resonance 1H-NMR method was developed and applied to screen the quantity of the diterpenic resin acids in the heartwood of black pine, due to the renewed scientific interest in their medicinal properties and use in various diseases treatment. The 260 samples were taken from Pinus nigra clones, selected from four provenances of the Peloponnese (Greece), participating in a 35-year-old clonal seed orchard. Total resin acids per dry heartwood weight (dhw) varied greatly, ranging from 30.05 to 424.70 mg/gdhw (average 219.98 mg/gdhw). Abietic was the predominant acid (76.77 mg/gdhw), followed by palustric acid (47.94 mg/gdhw), neoabietic acid (39.34 mg/gdhw), and pimaric acid (22.54 mg/gdhw). Dehydroabietic acid was at moderate levels (11.69 mg/gdhw), while levopimaric, isopimaric, and sandaracopimaric acids were in lower concentrations. The resin acid fraction accounted for 72.33% of the total acetone extractives. Stilbenes were presented in significant quantities (19.70%). The resin acid content was composed mainly of the abietane type resin acids (83.56%). Peloponnesian Pinus nigra heartwood was found to be the richest source of resin acids identified to date and is considered the best natural source for the production of such bioactive extracts. The results indicate a high potential for effective selection and advanced breeding of pharmaceutical and high economic value bioactive substances from Pinus nigra clones.
Project description:The <i>Pinus nigra</i> distribution in Portugal is restricted to six allochthonous populations with unknown origin and infraspecific taxonomy. This work intends to evaluate their genetic diversity, structure and relationships, and to infer about their infraspecific taxonomy by comparing molecular patterns produced by inter-simple sequence repeat and Start Codon Targeted markers among Portuguese and foreign samples with known taxonomy and provenance. 127 Portuguese <i>P. nigra</i> individuals were clustered per population. The genetic differentiation was higher within rather than among populations. The pooled molecular data indicated high genetic proximity among the Portuguese and foreign samples of subspecies <i>laricio</i>. However, the separate analysis per marker system demonstrated that two varieties of subspecies <i>laricio</i> (<i>corsicana</i> and <i>calabrica</i>) may have been used in the plantations of the Portuguese <i>P. nigra</i> stands performed in the last century. The genetic characterization and extrapolation of the intraspecific taxonomy of these populations provide useful information for forest management, afforestation and germplasm use.
Project description:This article contains tree rings data related to the research article entitled "An intra-stand approach to identify intra-annual growth responses to climate in Pinus nigra subsp. laricio Poiret trees from southern Italy" (Mazza et al., 2018). Most dendroclimatological studies on black pine have been conducted on the P. nigra subsp. nigra, while only few results on climate-growth relationships are available for other taxa such as P. nigra subsp. laricio, which has the narrowest distribution range of the collective species P. nigra. This data article provides tree rings data for the subsp. laricio at an intra-annual growth level, distinguishing early-wood (EW) and late-wood (LW), from an even aged forest stand from the Sila mountain area within the subspecies mesic to xeric distribution range.
Project description:There are several issues complicating somatic embryogenesis in conifers, for instance the low initiation frequency, the weak maturation capacity, and the loss of an embryogenic potential after a prolonged cultivation. The aim of our study was to clarify molecular details of the this process in the tree Pinus nigra Arn. We performed comparative proteomic analysis based on the two-dimensional gel electrophoresis in 2 genotypes coded 362 and 366 of: 1) proliferating embryogenic tissues (E) initiated from immature zygotic embryos, 2) non-embryogenic calli (NEC) started from cotyledons of somatic seedlings, 3) embryogenic tissues that lost the maturation capacity (E-L). Pine tissues showed distinct morphologic features: a) E362 and E366 were characterized by the presence of early bipolar structures capable of maturation and plantlet regeneration; b) NEC362 and NEC366 were composed of round shaped cells without any organisation; c) for E-L362 and E-L366 the long-term culture of initially embryogenic tissues resulted in the disorganisation of early bipolar structures. We found 24 differentially accumulated protein spots common for both genotypes after comparison of E versus NEC.
Project description:1. The degradation of (+)-alpha-pinene biosynthesized from 3RS-[2-(14)C]mevalonate by Pinus radiata or Pinus nigra revealed an asymmetrical labelling pattern whereby the moiety derived from isopentenyl pyrophosphate contained at least 90% of the incorporated tracer. This pattern differed both in asymmetry and position of labelling from previous results obtained with P. nigra, but is consistent with the generally accepted hypothetical mechanism for the biosynthesis of the pinane skeleton. 2. (+)-alpha-Pinene biosynthesized in Pinus attenuata and in the previously named two species from 3RS-[2-(14)C,(4R)-4-(3)H(1)]mevalonate and its (4S)-isomer retained all the 4R hydrogen atoms (within the experimental error) but lost all the 4S hydrogen atoms of the precursor. This stereospecificity of hydrogen loss is the same as that previously found for the formation of geraniol and nerol in other plant species, and the result may be reasonably inferred to be general for monoterpenes.
Project description:Ongoing climate change is apparently increasing tree mortality rates, and understanding mechanisms of drought-induced tree decline can improve mortality projections. Differential drought impact on conspecific individuals within a population has been reported, but no clear mechanistic explanation for this pattern has emerged. Following a severe drought (summer 2012), we monitored over a 3-year period healthy (H) and declining (D) Pinus nigra trees co-occurring in a karstic woodland to highlight eventual individual-specific physiological differences underlying differential canopy dieback. We investigated differences in water and carbon metabolism, and xylem anatomy as a function of crown health status, as well as eventual genotypic basis of contrasting drought responses. H and D trees exploited the same water pools and relied on similar hydraulic strategies to cope with drought stress. Genetic analyses did not highlight differences between groups in terms of geographical provenance. Hydraulic and anatomical analyses showed conflicting results. The hydraulic tracheid diameter and theoretical hydraulic conductivity were similar, but D trees were characterized by lower water transport efficiency, greater vulnerability to xylem conduit implosion and reduced carbohydrate stores. Our results suggest that extreme drought events can have different impacts on conspecific individuals, with differential vulnerability to xylem embolism likely playing a major role in setting the fate of trees under climate change.
Project description:Stable isotope abundances convey valuable information about plant physiological processes and underlying environmental controls. Central gaps in our mechanistic understanding of hydrogen isotope abundances impede their widespread application within the plant and biogeosciences. To address these gaps, we analysed intramolecular deuterium abundances in glucose of Pinus nigra extracted from an annually resolved tree-ring series (1961-1995). We found fractionation signals (i.e. temporal variability in deuterium abundance) at glucose H<sup>1</sup> and H<sup>2</sup> introduced by closely related metabolic processes. Regression analysis indicates that these signals (and thus metabolism) respond to drought and atmospheric CO<sub>2</sub> concentration beyond a response change point. They explain ≈ 60% of the whole-molecule deuterium variability. Altered metabolism is associated with below-average yet not exceptionally low growth. We propose the signals are introduced at the leaf level by changes in sucrose-to-starch carbon partitioning and anaplerotic carbon flux into the Calvin-Benson cycle. In conclusion, metabolism can be the main driver of hydrogen isotope variation in plant glucose.
Project description:Increasing heavy metal pollution in the environment and the fact that pine needles are good bio-monitors for air pollutants was the reason to investigate their accumulation in pine needles in Vienna (Austria). <i>Pinus nigra</i> is widespread over the city, thus allowing the study of different parameters influencing metal accumulation. The sampling sites were chosen based on traffic volume (low, medium, high). Fresh shoots were collected alongside one-year-old needles once per week from May to August 2015. The needle samples were washed and dried prior to acidic microwave-assisted digestion followed by quantitative determination using spectrometric methods. The investigation was focused on the following elements: Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Se, Sr, U, V, and Zn. The one-year-old needles mainly contained higher contents of elements than fresh shoots; in many cases, the values differed statistically significantly. By correlating needle elemental contents with the sampling site, statistically significant differences were registered for the majority of the investigated elements. These differences originate from the local traffic situation, soil elemental levels, translocation processes, and not traffic-related sources. No general trend of metal accumulation from spring to summer was registered.