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NADPH: protochlorophyllide oxidoreductases in white pine (Pinus strobus) and loblolly pine (P. taeda). Evidence for light and developmental regulation of expression and conservation in gene organization and protein structure between angiosperms and gymnosperms.

NADPH: protochlorophyllide oxidoreductase (pchlide reductase, EC 1.6.99.1) catalyzes the light-dependent reduction of protochlorophyllide in higher plants. Cloned cDNAs encoding two distinct pchlide reductases were isolated from a lambda gt11 library constructed from poly(A)+ RNA prepared from the cotyledons of dark-grown white pine (Pinus strobus) seedlings and a nuclear gene (lpcr) analogous to one of these cDNAs has been characterized from loblolly pine (P. taeda). The pine gene encodes an approximately 43 kDa precursor polypeptide consisting of a 334-amino acid mature protein and a 66-amino acid transit peptide. The deduced primary structures for the pine proteins are highly homologous to those reported from monocots and dicots. The coding portion of the pine lpcr gene is interrupted by four introns. The placement of these introns within the pine lpcr gene is identical to that observed in pea (Pisum sativum), suggesting conservation in gene organization between dicot and gymnosperm species. Western blot analysis using polyclonal antiserum against oat pchlide reductase detected in extracts of dark-grown pine cotyledons a single immunoreactive protein, which declined in abundance during a 48 h period of illumination with white light. Cotyledons of dark-grown seedlings were also found to accumulate high levels of pchlide reductase mRNA; however, little or no change in the steady-state levels of mRNA encoding pchlide reductase was observed in these tissues following illumination. Stem tissue of dark-grown seedlings did not contain significant levels of pchlide reductase mRNA, whereas stems of light-grown plants of the same age accumulated substantial amounts of the message. These results suggest that light and the developmental age of the tissue affect regulation of lpcr expression in pine.

Amino Acid Sequence↗

[Isolation and structure identification of lignans from pine needles of pinus massoniana Lamb].

AIM: To study the chemical constituents from the water-extracts of pine needles of Pinus massoniana Lamb. METHODS: Chromatographic techniques were used to separate and purify compounds. Their physico-chemical properties and spectral data (UV, IR, MS, 1H-1H, 13C-1H NMR, DEPT, HMBC etc.) were used to elucidate the structures. RESULTS: Three lignans were isolated from the n-BuOH fraction of water-extracts. Their structures were identified as (7S,8R)-3',4,9'-tridihydroxy-4-methoxy- 9-O-shikimoyl-7,8-dihydrobenzofuran-1'-propylneolignan (massonianoid A, I), (7S,8R)-4,9-dihydroxy-3,3'-dimethoxy-7,8- dihydrobenzofuran-1'-propylneolignan (II) and 4,4',8-trihydroxy-4,4'-dimethoxy-9-lignanolide (III). CONCLUSION: Compound I is a new compound. While II and III were isolated from this plant for the first time.

Furans↗

[Comparative study of allozyme polymorphism in groups of pine trees (Pinus sylvestris L.) with different seed productivity].

Genotypes of 196 Pinus sylvestris L. plants from 10 natural populations of five Ukrainian regions have been determined using 19 polymorphic isozyme loci. Variability of quantity of full-grained, empty-grained and underdeveloped seeds in the cones of these plants has been studied. The basic indexes of genetic polymorphism were determined for 6 samples presented by 18-19 trees with high and low productivity of the full-grained, empty-grained and underdeveloped seeds. The maximum amount of rare alleles and genotypes as well as the highest heterozygosity (Ho = 0.285) were typical for the sample of plants with the maximum quantity of empty-grained seeds in the cones.

Alleles↗

[Isolation and structure identification of the chemical constituents from pine needles of Pinus massoniana Lamb].

AIM: To study the chemical constituents of the water-extracts of the pine needles of Pinus massoniana Lamb.. METHODS: Pine needles were collected in Xixia country and extracted with boiling water for two times and the water-extracts were concentrated. The crude extract of pine needles was fractionated into four fractions by Et2O, EtOAc and n-BuOH. Various column chromatography with D-101 macroreticular resin, Toyopearl HW-40 and silica gel were employed for the isolation and purification of compounds from the n-BuOH fraction of pine needles. The structures of the compounds were identified by physiochemical properties and spectral analysis (UV, IR, MS, 1HNMR, 13CNMR, DEPT, HMQC, HMBC, etc.). RESULTS: Four compounds were isolated from the n-BuOH fraction of water-extracts, and their structures were identified as 3-methoxyl-9'-O-alpha-L-rhamnopyranosyl-4':7,5':8-diepoxyneoligan-4,9-diol (massonianoside E, I), 4,4',8,8',9-pentahydroxyl-3,3'-dimethoxyl-7,9'-monoepoxylignan (II), umbelliferon (III), 4-(4'-hydroxyl-3'-methoxylbenzyl)-2-butanone (IV). CONCLUSION: Compound I is a new compound, and compounds II, III and IV were isolated from this plant for the first time.

Lignans↗

Diurnal and seasonal variability in the radial distribution of sap flow: predicting total stem flow in Pinus taeda trees.

We monitored the radial distribution of sap flux density (v; g H2O m(-2) s(-1)) in the sapwood of six plantation-grown Pinus taeda L. trees during wet and dry soil periods. Mean basal diameter of the 32-year-old trees was 33.3 cm. For all trees, the radial distribution of sap flow in the base of the stem (i.e., radial profile) was Gaussian in shape. Sap flow occurred maximally in the outer 4 cm of sapwood, comprising 50-60% of total stem flow (F), and decreased toward the center, with the innermost 4 cm of sapwood (11-15 cm) comprising less than 10% of F. The percent of flow occurring in the outer 4 cm of sapwood was stable with time (average CV < 10%); however, the percentage of flow occurring in the remaining sapwood was more variable over time (average CV > 40%). Diurnally, the radial profile changed predictably with time and with total stem flow. Seasonally, the radial profile became less steep as the soil water content (theta) declined from 0.38 to 0.21. Throughout the season, daytime sap flow also decreased as theta decreased; however, nighttime sap flow (an estimate of stored water use) remained relatively constant. As a result, the percentage of stored water use increased as theta declined. Time series analysis of 15-min values of F, theta, photosynthetically active radiation (PAR) and vapor pressure deficit (D) showed that F lagged behind D by 0-15 min and behind PAR by 15-30 min. Diurnally, the relationship between F and D was much stronger than the relationship between F and PAR, whereas no relationship was found between F and theta. An autoregressive moving average (ARIMA) model estimated that 97% of the variability in F could be predicted by D alone. Although total sap flow in all trees responded similarly to D, we show that the radial distribution of sap flow comprising total flow could change temporally, both on daily and seasonal scales.

Circadian Rhythm↗

Influences of excessive Cu on photosynthesis and growth in ectomycorrhizal Pinus sylvestris seedlings.

Growth and photosynthesis responses were measured for Scots pine (Pinus sylvestris L. cv.) inoculated with ectomycorrhizal fungi (Suillus bovinus) under 6.5 and 25 mg/L Cu treatments to evaluate ectomycorrhizal seedlings' tolerance to heavy metal stress. Results showed that excessive Cu can significantly impair the growth and photosynthesis of pine seedlings, but such impairment is much smaller to the ectomycorrhizal seedlings. Under 25 mg/L Cu treatment, the dry weight of ectomycorrhizal seedlings is 25% lower than the control in contrary to 53% of the non-mycorrhizal seedlings, and the fresh weight of ectomycorrhizal roots was significantly higher than those of non-mycorrhizal roots, about 25% and 42% higher at 6.5 and 25 mg/L Cu treatments respectively. Furthermore, ectomycorrhizal fungi induced remarkable difference in the growth rate and pigment content of seedlings under excessive Cu stress. At 25 mg/L Cu, the contents of total chlorophyll, chlorophyll-a and chlorophyll-b were 30% higher in ectomycorrhizal plants than those in non-mycorrhizal plants. O2 evolution and electron transport of PSI and PSII were restrained by elevated Cu stress. However, no significant improvement was observed in reducing the physiological restraining in ectomycorrhizal seedlings over the non-mycorrhizal ones.

Chlorophyll↗

Fungicidal properties of Pinus sylvestris L. for improvement of air quality.

Sick building syndrome is a term commonly used to describe the consequences of poor indoor air quality. It is well documented that first of all air quality depends on the chemical composition, and until now negligible attention has been paid to air pollution by microorganisms. Some species of fungi (Aspergillus flavus, A. fumigatus, A. niger, A. parasiticus, A. oryzea and other) and their toxins cause difficulty in breathing, allergic rhinitis, watery eyes, headaches, and flu-like symptoms. Over recent years considerable interest has been developed for plant extracts that would be of great use for the improvement of air quality. The biological activity of Pinus sylvestris L. has been investigated in order to find out its fungicidal activity against airborne microorganisms. It was determined, that fungi from Aspergillus and Penicillium genera dominated indoors. Antimicrobial activity of pine oil was evaluated by technique of oil diffusion to Czapek agar (for fungi), malt extract agar (for yeast and yeast-like fungi) and nutrient agar (for bacteria). Minimum inhibitory concentrations of pine oil to 13 species (8 fungi, 2 yeast-like fungi, yeast and 2 bacteria,) were determined: 1.0-2.5, 1.0-1.2, 0.5-0.75, and 0.75-1.2% (v/v), respectively. According to resistance to pine oil action, microorganisms grouped themselves as following: fungi, spore bacteria, yeast-like fungi, yeast, and bacteria (fungi being the most resistive and bacteria being the least resistive). The most active concentration of pine oil against all tested microorganisms was 2.5%, and the most sensitive fungus to volatiles was Ulocladium oudemansii.

Air Microbiology↗

[Study of some characteristics of morphogenesis and germination of Pinus pallasiana D. Don. pollen].

Investigation of Pinus pallasiana D. Don. pollen morphogenesis in natural forest plantations of the southern slope of the Main ridge of Crimean mountains has been carried out. Some abnormalities of pollen grain and pollen tube formation in the course of pollen germination in vitro are described. The dynamics of developmental abnormalities of P. allasiana male gametophyte is characterized.

Germination↗

Reciprocal controlled crosses between Pinus sylvestris and P. mugo verified by a species-specific cpDNA marker.

A species-specific marker of cpDNA (paternally inherited in pines) was used to verify the hybrid origin of seedlings from controlled reciprocal crosses between Pinus sylvestris and P. mugo. A very low degree of compatibility between those two species has been revealed. In the three consecutive years of experiments, no filled seeds were obtained in the combination with P. mugo as the seed parent. From P. sylvestris as the seed parent and P. mugo as the pollen donor, we succeeded to obtain four filled seeds (about 1 %), but only in one year. The seedling obtained from the seeds had cpDNA haplotypes specific to P. mugo, which proves their hybrid origin. This method enables verification of the result of controlled crosses. The importance of the results has been discussed in the aspect of postulated natural hybridisation in sympatric populations of the two species.

DNA, Plant↗

[Population-genetic variation in Scots pine Pinus sylvestris L. from the main forest regions of Ukraine].

Using electrophoretic analysis of 22 isozyme loci controlling ten enzyme systems, we studied intrapopulation and interpopulation variation of Scots pine Pinus sylvestris L. in the main forest regions of Ukraine. In 15 of the populations examined, 76.5% of genes were polymorphic, and an average plant was shown to be heterozygous at 23.4% of the genes. The lowest and highest values of major polymorphism parameters were characteristic of respectively the relic populations of Ukrainian Carpathians and the populations from the steppe and forest-steppe zones. Nei's genetic distances between the populations varied from 0.006 to 0.031 (on average 0.016). Cluster analysis failed to show clear trends in the population distribution relative to their geographical position.

Alleles↗

[Stem respiration of Pinus koraiensis in Changbai Mountains].

In this paper, soil respiration chamber, a simple and precise method, was used to measure the stem respiration of trees. LI-6400-09 respiration chamber serving as a system is usually used in soil respiration, but we made polyvinyl chloride (PVC) collar and fixed it on the stem surface to measure the stem respiration. From May to October 2003, the stem respiration of Pinus koraiensis, the dominant tree species in Changbai Mountain, was measured in different time and different places using this technique. Meanwhile, the temperatures in the stems and in the forests were measured. The results showed that the stem respiration rate had a remarkably seasonal tendency with a single peak, the maximum was in August and the minimum was in February. The stem respiration rate had an exponential relationship with stem temperature, and the curve exponential regressions for stem respiration rate and temperature factor of trees with big DBH were better than those with small DBH. The stem respiration in different DBH trees was higher in the south stem face than that in the north stem face, and the variance of respiration rate between south and north decreased with a decrease of DBH trees. During the growing season from May to October, the average maintenance respiration accounted for 63.63% in different DBH trees, and the maintenance respiration contribution to total respiratory consumption increased with increasing DBH, which was 66.76, 73.29% and 50.84%, respectively. The stem respiration Q10 values ranged from 2.56-3.32 in different DBH of trees, and the seasonal tendency for stem R, and Rm in different DBH of trees was obtained by using respiration Q10. Therefore, the differences between different parts of stem and different DBH of trees should be considered in estimating the respiration model in ecosystem.

Air↗

[Root biomass of different stand-age Pinus yunnanensis forests and its distribution pattern in different soil depths].

With average-tree-specific sampling method, the authors measured the root biomass of Pinus yunnanensis forests with different stand ages in Yongren County, Yunnan Province. The results indicated that total root biomass increased from 8.50 t x hm(-2) in young stand (15-17 yr) to 11.70 t x hm(-2) in middle-aged stand (30-32 yr), and to 18.91 t x hm(-2) in mature stand (60-130 yr). Among different stand age classes, the biomass of coarse roots (>10 mm) varied greatly (1.5-12.3 t x hm(-2)), whereas those of medium (5-10 mm) and fine (<5 mm) roots showed less variation (medium roots 1.4-1.6 t x hm(-2), fine roots 5.3-6.2 t x hm(-2)). The root biomass of mature stand decreased with soil depth, approximately 93% of total underground biomass being distributed in surface layer (0-30 cm), and only 7% in deeper layer (30-115 cm).

China↗

[Effects of artificial tending on Pinus tabulaeformis forest growth and its structural characteristics].

The investigation on the growth status, community composition, and structural characteristics of Pinus tabulaeformis forest artificially tended for six years showed that there were significant differences in the average DBH, height, and crown size of the forest among the treatments DA (trimming without intermediate cutting), FA (trimming and intermediate cutting) and CK (without trending). Treatment FA had the highest values of average DBH (7.8 +/- 0.29 cm), height (5.5 +/- 0.09 m) and crown size (249 +/- 7.24 cm), while the CK had the lowest ones. The average biomass of new leaf (1-year-old), old leaf (2 or more-year-old), and branch per tree increased significantly (P<0.01) with enhancing tending treatments. The aboveground biomass of treatment FA was the biggest (44.0 t x hm(-2)), and that of CK was the smallest (14.9 t x hm(-2)). The leaf length and SLA at the early and terminal stages of development (May, June and September) had significant difference among the treatments, and the amount of community composition and the cover degree of undergrowth plants increased evidently under artificial tending treatments.

Biomass↗

[Studies on chemical constituents from pine cone of Pinus armandii].

OBJECTIVE: To study chemical constituents from pine cone of Pinus annandii. METHOD: The constituents were isolated by chromatographic method and the structures were identified on the basis of spectral analysis. RESULT: Seven compounds were identified as sandaracopimaric acid (I), isodextropimaric acid (II), 12-hydroxyabietic acid (III), dehydroabietic acid (IV), 15-hydroxydehydroabietic acid (V), beta-sitosterol (VI) and daucosterol (VII). CONCLUSION: Compounds I-IV were isolated from this plant for the first time.

Abietanes↗

[Variability of the cytological parameters of Pinus sylvestris L. seeds from the unique Hrenovskoy pine forest].

Hrenovskoy pine forest is a unique island stand at the boundary of the species range of Scots pine Pinus sylvestris L. This object is of exceptional economic value, because it serves as a forest-seed base for the Voronezh oblast and some other regions of Russia; therefore, the stand and seed qualities have to be monitored constantly. The results of the first cytogenetic study of the seed progeny of P. sylvestris from the Morozov Grove, a high-quality stand in a reserved site within the Hrenovskoy pine forest, are reported. The studies have been performed in order to obtain a more correct assessment of seed quality based not only on their germination and energy of germination (traditionally used by forest breeders), but also on their genomic stability. The latter may be estimated by the stability of chromosome number in the somatic cells of seedlings and the regularity of mitotic divisions, because they also characterize the state of the generative system of parental forms and may serve as an integrated estimate of the stand development homeostasis. Therefore, the chromosome number, mitotic and nucleolar activities, and the number and spectrum of pathological mitoses (PMs) have been determined. Seedlings have been obtained from 240 seeds (collected from 12 trees) that resulted from free pollination. The cytological analysis of the rootlets of these seedlings has not detected any deviations from the chromosome number typical of the species P. sylvestris L. (2n = 24). However, considerable variation has been found in each family with respect to the mitotic index (MI) (from 4.2 +/- 0.36 to 8.1 +/- 0.39%) and the number of PMs (from 0.5 to 2.1%); micronuclei have also been found in each family (from 0.01 to 0.05%). In general, the phenotypic characteristics and the variation pattern of cytological parameters of the progeny of the trees studied in the Hrenovskoy pine forest, together with the high germination rate of seeds (90-98%), indicate that the current state of pines in the Hrenovskoy pine forest can be considered to be satisfactory. However, the presence of micronuclei in all variants and the decrease in MI in some individual plants (which was, on average, 6.1 +/- 0.03% in the sample studied, i.e., significantly lower than that of P. sylvestris from the Usmanskii pine forest (7.3 +/- 1.2%), where the conditions are optimal for this species) may serve as the bioindicators of the deterioration of both the state of trees themselves and the ecological conditions in the Hrenovskoy pine forest. Therefore, the population structure of this valuable autochtonic stand should be reproduced urgently.

Genomic Instability↗

[Effects of polyethylene glycol (PEG)-simulated drought stress on Pinus sylvestris var. mongolica seed germination on sandy land].

With introduced sandy land Mongolian pine (Pinus sylvestris var. mongolica) seeds as test material, this paper studied the effects of polyethylene glycol (PEG)-simulated drought stress on their germination. The results showed that PEG could retard the germination of stressed seeds, and the germination rate, germination index, and germination potential were all decreased with increasing PEG concentration. The seeds treated with 30% PEG (about -1.20 MPa water potential) could not germinate at all throughout the experiment period, suggesting that 30% PEG or -1.20 MPa water potential was the threshold for the germination of Mongolian pine seeds. Under 10% PEG stress (about -0.20 MPa water potential), the lengths of radicle and hypocotyl were shorter, illustrating their growth be more sensitive to PEG-simulated drought stress, while the radicle/hypocotyl ratio was increased with increasing PEG concentration, indicating that Mongolian pine seeds had a stronger resistance to drought stress after germination. Drought stress might be a possible cause that inhibited the natural regeneration of Mongolian pine on sandy land.

Desert Climate↗

[Dynamic characters of sulphur and heavy metals concentrations in Pinus taiwanensis growth rings].

Based on the concentration analyses of S, Mn, Fe, Zn, Cu and Pb in the growth ring set of Pinus taiwanensis at the summit (1,400-1,600 m alt.) of Huangshan Mountains during past 80 years, this paper studied the dynamic characters of element concentrations in the ring set, and their relationships with atmospheric environment. The results showed that there were three levels of S concentration in the growth ring set, i.e., low concentration (less than 2 mg.kg(-1)), accounted for 58.5% of the ring set; medium (3.65-6.0 mg.kg(-1)), accounted for 24.4%; and high ( > 11.0 mg.kg(-1)), accounted for 17.1%. The dynamic change of S accumulation in the ring set displayed an obvious fluctuation, which could be divided into 3 major types, i.e., fluctuation during 1917-1960, relatively stable during 1961-1980, and gradual increase after 1981. In the growth ring set of 1935-1938, 1959-1960, and recent 10 years, the S accumulation concentrations were all higher than 11 mg.kg(-1), suggesting the relatively high atmospheric S concentration in those periods. There was a significant correlation between the increase of tourist amount in Huangshan scenic spot and the S concentration in growth ring set. The fuel fume centralized in some places might result in the atmospheric pollution at local scale, which in turn, might influence the S accumulation in growth ring set. The Pb accumulation concentration in the ring set was less than the background value in soil. The accumulation concentrations of Mn, Fe, Zn and Cu showed fluctuation characteristics, with independence of each other. The accumulation of Zn and Cu in growth rings had no correlation with tree age, while that of Mn and Fe was in adverse. The Mn concentration in the growth ring set decreased with tree age but increased in recent growth rings, while the Fe concentration was on the contrary, which needed further study.

Metals, Heavy↗

[Analysis of genetic heterogenicity of seed embryos in trees characterized by different seed productivity in Crimean population of Pinus pallasiana D. Don].

A comparative analysis of allozyme variability has been conducted for 10 polymorphic loci of samples of seeds and maternal plants characterized by significant differencies in productivity of empty and full-grained seeds in Pinus pallasiana D. Don population in Crimea. It has been determined that allele diversity is fully reproduced in seed progeny of plants of distinguished samples. However, their genetic structure is deviated because of heterozygote deficiency.

Alleles↗