Seeds Of Pinus Pinea Research Articles

Occurrence of fungi, with emphasis on Diplodia pinea, in pine seeds from forest nurseries of Turkey

Diplodia sapinea severely damages conifers and significantly reduces seed production and germination when cones are infected with the pathogen. In this study we aimed to determine the presence of D. sapinea and other fungi on seed of pines. A selective medium was used to isolate D. sapinea from Pinus brutia, Pinus nigra and Pinus pinea seeds obtained from forest nurseries in Antalya, Balıkesir, Denizli, Eskişehir and Isparta. Morphological and molecular analysis showed that D. sapinea was isolated from 4% to 1% of Pinus pinea and P. brutia seeds. Fungal colonies other than D. sapinea isolated from seeds on the selective medium were also identified morphologically. The most common species found were Sydowia polyspora, Alternaria alternata, Aspergillus niger, Fusarium spp., Fusarium oxysporum and Rhizoctonia solani, which are harmful to seeds, were also isolated. Other fungi isolated from the seeds were Trichoderma harzianum, Aureobasidium pullulans, Trimmatostroma salicis, Rhizoctonia solani, Chaetomium globosum, and Stephylium spp.

Glyoxylate cycle activity in Pinus pinea seeds during germination in altered gravity conditions

This work inserts in the research field regarding the effects of altered gravity conditions on biological plant processes. Pinus pinea seeds germination was studied in simulated microgravity (2x10−3g) and hypergravity (20g) conditions.The effects of simulated gravity were evaluated monitoring the levels of the key enzymes, involved in the main metabolic pathway during germination process of lipid–rich seeds (oilseeds): isocitrate lyase and malate synthase for glyoxylate cycle, 3-hydroxyacyl-CoA dehydrogenase for beta-oxidation, isocitrate dehydrogenase for Krebs cycle, pyruvate kinase for glycolysis and glucose 6 phosphate dehydrogenase for pentose phosphate shunt. The simulated micro and hypergravity conditions were obtained by a Random Position Machine and a Hyperfuge, respectively.Results show that the levels of some tested enzymes, at different lag times of the germination process, have the same trend of controls (g = 1), but with significant differences from quantitative point of view. They are higher in microgravity conditions and lower in hypergravity ones, suggesting that, from a biochemical point of view, the germination process results accelerated in microgravity conditions and delayed in hypergravity ones. These biochemical results show a good correlation with morphological ones, obtained with the measurement of the length of the seeds sprouting radicle.These results give promising indications regarding the possibility to grow plant with lipid-rich seeds in spatial environment, to obtain food sources for astronauts during long term space missions and to reconstitute new atmosphere.

Is Leptoglossus occidentalis entirely responsible for the high damage observed on cones and seeds of Pinus pinea? Results from a fertirrigation trial in Portugal

The uncertainty surrounding the part played by an invasive North American seed bug, Leptoglossus occidentalis, in the observed decrease in seed production of the Mediterranean pine, Pinus pinea, is a limiting factor for its management. Furthermore, the possibility of increasing cone production through irrigation and fertilization regimes is gaining interest among landowners, but its effects on insect pests are still unknown.Using bagged branches in the field, we aimed at evaluating the impact of L. occidentalis on young and mature cones of stone pine trees submitted to fertirrigation (FR) compared to trees with no treatment (C). For two consecutive years (2015 and 2016), we carried out both an insect-exclusion trial and an insect-bagged trial. In the first one, polyester-covered branches, excluding insects, were compared to branches exposed to natural insect infestation. In the second trial, bags included either two adult bugs or 3–4 third-instar nymphs, placed there for one month during mid-summer, or were kept without insects. Branch protection resulted in a significant decrease in the mortality of second-year conelets which dropped to 6% compared to 30% in exposed branches. Seed damage also decreased from 60% on exposed branches to 10% on protected ones. The presence of nymphs in the bags resulted in a mortality of second-year conelets 63% higher than in exclusion bags, whereas adults had no effect. In contrast, bags with adults presented the highest seed damage. The partial damage of the kernel can be a signature of L. occidentalis feeding since such damage was not observed in exclusion bags. Additionally, another type of seed damage, showing a wholly shrunken and dry embryo without remaining endosperm, and a reduction in the number of extractable seeds may also be attributed to this seed bug. Overall, seed damage per mature cone reached up to 12% in bags with two adult bugs enclosed for a month, i.e., twice the seed damage in protected cones. Overall, FR trees were more susceptible to both conelet mortality and seed damage. In the particular case of L. occidentalis, FR regime influenced the consumption positively by the nymphs but not by adults.

Long-term storage of eggs of Leptoglossus occidentalis for the mass-rearing of its parasitoid Gryon pennsylvanicum

Leptoglossus occidentalis Heidemann (Heteroptera, Coreidae) is a harmful insect to cones and seeds of several conifers in North America, and was accidentally introduced into Europe where it rapidly spread to many countries. In Central Italy, the pest damaged cones and seeds of Pinus pinea L., leading to a severe reduction of pine nut production. Gryon pennsylvanicum (Ashmead) (Hymenoptera, Platygastridae) is the most common egg-parasitoid of L. occidentalis in British Columbia. This natural enemy has been successfully reared under laboratory conditions. However, the possibility to arrange a sufficient large number of specimens is crucial for the success in biological control. In the present work, stored L. occidentalis eggs at fridge and freezing temperatures of +4, −20 °C, and ultra-low temperatures of −80 and −140 °C for different times up to one year, were tested for parasitization success. Results showed that G. pensylvanicum can exploit successfully host eggs stored for long time when stored at ultra-low temperatures and that storage did not affect fitness of the first and second generation. For shorter periods of time, the use of +4 °C for store eggs did not vary significantly from eggs stored at ultra-low temperatures.

The Effects of Feeding Pinus Pinea Seeds on Some Blood Values in Male New Zealand White Rabbits

The Effects of Feeding Pinus Pinea Seeds on Some Blood Values in Male New Zealand White Rabbits

Drought, salinity and heat differently affect seed germination of Pinus pinea

Drought, salinity and forest fires are adverse abiotic factors responsible for the failure of plant regeneration in the Mediterranean regions. The objective of this study was to evaluate Pinus pinea seed germination in response to heat, osmotic and salinity stress. Separate experiments were conducted, using polyethylene glycol (PEG) as an osmotic agent to reproduce drought stress, and sodium chloride (NaCl) and diluted seawater as salinizing agents to simulate salinity stress. Different temperatures were used to reproduce the effects of different fire regimes. Seed germination and the activities of the main enzymes involved in Pinus seed reserve utilization (glyoxylate cycle enzymes) decreased with increasing PEG, NaCl and seawater concentrations. Seawater appears to be the least toxic salinizing agent on Pinus pinea seed germination. The present study indicates that the germination of Pinus pinea seeds is influenced by the concentrations and even more by the nature and interactions of the ions present in the solutions. As regard heat treatments, the maximum germination percentage (80%) was obtained at 80°C and short exposure time (3 min). Increasing exposure time and temperature led to the germination percentage progressively decreasing.

Anaphylaxis to pine nut: cross-reactivity to Artemisia vulgaris?

The use of pine nuts, the seeds of Pinus pinea, is on the increasing in the modern Mediterranean diet. Little more than 20 cases of allergy to this tree nut have been published, and cross-reactivity with pine pollen, peanut and almond has already been reported. We describe the case of a young boy with several episodes of anaphylaxis after pine nut ingestion. Specific IgE to pine nut and Artemisia vulgaris was demonstrated by skin prick tests and in vitro determination of specific IgE, although no IgE to pine pollen or other nuts was detected. Immunoblotting of Artemisia vulgaris and pine nut revealed two matching diffuse bands, just below 14 kDa and 30 kDa. The ImmunoCAP inhibition assays showed complete inhibition of pine nut specific IgE after serum incubation with Artemisia vulgaris extract. As far as we know, this is the first reported case of documented cross-reactivity between pine nut and Artemisia vulgaris.

Changes in germination and glyoxylate and respiratory enzymes of Pinus pinea seeds under various abiotic stresses

This study examined Pinus pinea seeds for their tolerance to osmotic potentials of −0.30MPa (10% polyethylene glycol [PEG]), −0.58MPa (18% PEG), −0.80MPa (21% PEG), −1.05MPa (24% PEG), pH values of 4, 5, 6, 7, 8, 9, 10, and different calcareous solutions (5, 10, 20 and 40% CaCO3). The main enzymes of glyoxylate cycle and respiratory pathway were tested. Pinus pinea seeds under no stressful condition (Control) and 5% CaCO3 reached 100% of germination. Higher concentrations of CaCO3 (20, 40%) and lower pH (4–5) adversely affected seed germination percentage, glyoxylic and respiratory enzyme activities. PEG caused the most detrimental effects on Pinus seeds; increasing the osmotic potential the germination was completely inhibited. These results suggest that Pinus pinea is able to germinate in calcareous and alkaline soils rather than in soils with lower water availability and acidic conditions.

Fatty acids from seeds of Pinus pinea L.: Composition and population profiling

Pinus pinea L. is widely disseminated all over the Mediterranean Basin. Qualitatively, P. pinea fatty acid seed composition is identical and typical of the genus Pinus. This composition is made of unsaturated oil with several unusual polymethylene-interrupted unsaturated fatty acids. Linoleic acid is the major fatty acid followed by oleic, palmitic and stearic acids. Quantitatively, for all Mediterranean populations, total amounts of fatty acids seem to be fairly constant and independent from their origin. When applying principal component analysis, it seems that there is not a distinct geographical variability. Tunisian populations appear to be integral part of the Mediterranean populations without any particular structuring. Taking into account this research and the data reported in the literature, we can confirm that P. pinea expresses no significant variability. This low genetic diversity revealed by fatty acid composition can be explained by anthropogenetic diffusion of genetically homogeneous reproductive material as early as the first explorations.

Gravitational stress on germinating Pinus pinea seeds

In the germination of lipid-rich seeds, the glyoxylate cycle plays a control role in that, bypassing the two decarboxylative steps of the Krebs cycle; it allows the net synthesis of carbohydrates from lipids. The activity of isocitrate lyase, the key enzyme of the glyoxylate cycle, is an indicator of the state of seed germination: stage of germination, growth of embryo, activation and progress of protein synthesis, depletion of lipidic supplies. In order to investigate the effects of gravity on seed germination, we carried out a study on the time pattern of germination of Pinus pinea seeds that were subjected to a hypergravitational stress (1000 g for 64 h at 4 °C), either in a dry or in a wet environment, before to be placed in germination plates. During the whole time of germination, we monitored the state of embryo growth and the most representative enzymes of the main metabolic pathways. In treated wet seeds, we observed an average germination of only 20% with a slowdown of the enzyme activities assayed and a noticeable degradation of lipidic reserves with respect to the controls. These differences in germination are not found for dry seeds. To cite this article: F. Ranaldi et al., C. R. Biologies 326 (2003).

Chlorophyll accumulation in cotyledons, hypocotyls and primary needles of Pinus pinea seedlings in light and dark

Seeds of Pinus pinea L. were germinated and grown in darkness or under natural photoperiodic (day/night) conditions for 8 weeks. Samples were taken for analysis at frequent intervals and chlorophyll (Chl) and protochlorophyllide (Pchlide) contents of cotyledons, hypocotyls and primary needles determined spectrophotometrically alter separating the esterified from unesterified pigments by partitioning between ammoniacal acetone and petroleum ether. Chlorophyll accumulated in cotyledons, hypocotyls and primary needles of dark as Well as light grown seedlings. The maximum Chl concentrations achieved in darkness in these organs were approximately 60, 20 and 10% respectively, of concentrations achieved in light. The tinsel of rapid Chl accumulation by cotyledons in darkness coincided with the emergence of the radicle from the seed. Light had no effect on the timing of this process or on the duration of the lag period. However, it extended the exponential growth phase of cotyledons by at least a week and. once the seedlings were about 2 weeks old, enabled Chl to accumulate at a faster rate. Time courses of Chi and Pchlide accumulation by cotyledons in darkness were similar. Pchlide did not accumulate prior to the onset of Chi accumulation and Chl slopped accumulating once the Pchlide pool reached maximum size. The implications of these findings are discussed and a hypothesis to account for the inability of primary needles of smaller seeded pines to accumulate Chl in darkness is proposed.

Evidence for separate intermediates in the biosynthesis of 24α- and 24β-alkylsterols in tracheophytes

When mevalonate-[2- 14C] was incubated with seeds of Pinus pinea, 23% of the label in sterols was found in trans-24-ethylidenecholesterol, 12% in a mixture of 24α- and 24β-methylcholesterol, and 65% in 24α-ethylcholesterol. However, when the radioactive substrate was lanosterol-[24- 3H], label appeared only in the 24-ethylidene- (85%) and the epimeric 24-methylsterols (15%). From the ratios of labels in the ethylidene- and methyl-sterols it was possible to show that the tritium in the 24-C 1 -mixture was incorporated only into the 24β-methyl epimer. The labelling patterns are consistent with a pathway to 24β-alkylsterols via Δ 25(27)-sterols bypassing 24-ethylidenesterols and to 24α-alkylsterols via Δ 24(28)-sterols which are isomerized to Δ 24(25)-sterols prior to reduction.

Evidence of glyoxysomes in germinating pine seeds

By means of differential centrifugation, assay of enzyme activity and electron microscopy, the occurrence of glyoxysomes was demonstrated in germinating Pinus pinea seeds. All the enzyme activities of the glyoxylate cycle were found in the glyoxysome fraction. The specific activity of isocitrate lyase, located in this organelle, increased during germination of the seed. Electron microscopy of three different zones of the endosperm showed a gradual disappearance of lipid bodies and aleurone grains while glyoxysomes, mitochondria and membrane systems increased during germination. The most abundant organelles in vacuolated cells were the glyoxysomes, which seemed to be closely associated with the rough endoplasmic reticulum.

The Effects of Octanoate and Oleate on Isocitrate Lyase Activity during the Germination of Pinus pinea Seeds

The changes of isocitrate lyase levels with respect to the catabolism of triglycerides have been studied during the germination of Pinus pinea seeds. We studied the effects of octanoate, oleate, and inhibitors of protein synthesis on isocitrate lyase during germination. Pyruvate kinase, glucose-6-P-dehydrogenase, malate dehydrogenase, and isocitrate dehydrogenase were also assayed. Octanoate and oleate inhibited the isocitrate lyase activity, similarly to cycloheximide, chloramphenicol, and actinomycin, inhibitors of protein biosynthesis. This inhibitory effect is not specific but is strikingly evident with isocitrate lyase. This inhibition was not proportional to the concentration but was proportional to the chain length of oleate and octanoate.

The Conversion of Mevalonate to 24-Methylenecycloartanol by a Cell-free Enzyme Preparation from Nonphotosynthetic Tissue

Abstract A cell-free enzyme preparation has been obtained from the endosperm of germinating seeds of Pinus pinea which is capable of converting mevalonate to 24-methylenecycloartanol. The intermediates, squalene and cycloartenol, were also identified, but lanosterol, its 24-methylene analog, 4-monomethyl, and 4-desmethyl sterols were not formed. Since the enzymatic apparatus for opening the 9, 19-cyclo grouping and for demethylation at C-4 were absent, an experimental block following cyclization and introduction of the methylene group was provided. The absence of Δ8 compounds thus implies that the endosperm does not contain a squalene oxide to lanosterol cyclase. From this information we tentatively conclude that endosperm tissue, which is not functionally photosynthetic, biosynthesizes sterols through cycloartenol rather than lanosterol. This suggests in turn that the entirety of a photosynthetic organism, rather than just photosynthetic tissue, operates the steroid pathway through the cycloartenol route.

Biochemical and cytological studies on developing cotyledons of Pinus pinea following X-irradiation of dry seeds

The cotyledons in dry seeds of Pinus pinea which were selected for this study consisted exclusively of G1 cells. During germination of seeds, cells resume mitotic activity which stops before full cotyledon development. The quantity of DNA, RNA and protein in cotyledons and the incorporation of isotopically labelled precursors into these fractions have been measured at various developmental stages during germination of control and irradiated seeds (15 kR, 250 kVp X-ray). Concurrently, cytological investigations were carried out on mitotic activity, labelling index and chromosome aberrations. In irradiated cotyledons, the onset of DNA synthesis and mitotic activity were delayed by approximately 2 days; reduced synthesis of DNA, RNA and protein was also detected in irradiated cotyledons. Whereas accumulation of DNA was reduced 25 per cent by the end of the maturation period, cotyledon length was reduced by about 40 per cent. This radiation effect on cell elongation was found to be associated with a pronounced depression of RNA and protein synthesis in irradiated cotyledons during the elongation phase of development. Both RNA and protein synthesis were initiated in control and irradiated cotyledons by the 3rd day of germination, but were not inhibited in irradiated cotyledons until the 7th to 9th day; only lysine incorporation into protein was reduced on the 5th day. In the discussion an attempt has been made to correlate cytological and morphological effects of radiation with the synthesis of DNA, RNA and protein at various stages of cotyledon development.

The H-migration in the alkylation of sterols at C-24

1. 1. 24-Tritiolanosterol was prepared from lanosterol. 2. 2. Incubation in vivo of 24-tritiolanosterol with seeds of Pinus pinea yielded labeled 24-ethylidenecholesterol which was identified by ozonolysis to labeled 24-ketocholesterol. 3. 3. The position of the label in 24-ketocholesterol was shown to be C-25 by reduction to the labeled 24-hydroxy derivative followed by dehydration to desmosterol with loss of label. 4. 4. The results are in agreement with the predicted 1,2-H-migration 3 during alkylation of the Δ 24-bond.

The DNA Content of Nuclei in the Embryo of Dry Seeds ofPinus PineaandLactuca Sativa

SUMMARYThe DNA content of nuclei in the embryo of dry seeds of Pinus pinea and Lactuca sativa was determined by means of a Deeley type cytophotometer. It was found that in the root apex, shoot apex and cotyledon in Pinus and in the root apex and cotyledon in Lactuca all nuclei measured were 2C. Only in the root apex of one embryo (probably an immature seed) of Lactuca were both 2C and 4C nuclei found.The exclusive occurrence of 2C nuclei (G1 stage of the nuclear cycle for cells of meristematic type) in the embryo of Pinus pinea and Lactuca sativa is discussed. It is suggested that the situation found in the resting embryos of the two species reflects a strict control of the sequence of DNA synthesis and mitosis, probably bound to the genetic make-up of the species.

Modificazioni Anatomiche ed Istologiche in Apici Radicali di Plantule diPinus PineaL. Germinate in Vitro al Buio da Semi Immaturi

Abstract Histological and anatomical modifications in the root apex of PINUS PINEA L. seedlings grown in vitro from immature seeds, in the dark. — The seeds of Pinus pinea L. take three years to develop reaching maturity during the spring of the forth year. Immature seeds were collected at successive stages and cultivated in vitro in Heller's medium. The seedlings showed atrophy of the root togheter with histological and anatomical modifications of the root apex and formation of a small tuber. The extent of these modifications depends on the age of the seed and on how long the seedling is cultivated in vitro. Seedlings derived from seeds planted on August 31st and kept in vitro for about a month had an atrophic root through lack of meristematic capacity; in it the secretory and conducting apparatuses had developed but with mixed radical and hypocotilar characters. Seedlings from unripe seeds planted on September 30th and kept in culture for about one month showed an atrophic root owing to a rapid process of differentiation accompanied by the formation of isolated tracheid-like elements and of discontinuos vascular strands very near to the apex. Lateral proliferations gave rise to masses of various size of unorganised parenchyma which could separate the cortical and cap parenchyma from the central cylinder. In some cases the root cortex, clearly recognisable owing to an advanced process of differentiation, cut off from the central cylinder the root cap cells which degenerated. Seedlings obtained from seeds planted on October 11th and kept in culture for about one month showed a radical tubercle deriving from fasciation of the main axis which had ceased growing and had formed various abnormal lateral root primordia.