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We previously traced 10B-enriched boric acid from shoots to roots to demonstrate the translocation of boron (B) in Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seedlings. To gain a more detailed understanding of B translocation, we sought: (1) to demonstrate B retranslocation directly, by showing that foliar-applied 10B is located in the new growth after dormancy; and (2) to assess whether shoot-applied B affects growth in the long term. We applied 10B-enriched boric acid to needles of Scots pine and Norway spruce seedlings. After a dormancy period and 9 weeks of growth, small but significant increases in the 10B isotope were found in the new stem and needles of both species. In Scots pine, the total B concentration of the new stem was also increased. Both species contained polyols, particularly pinitol and inositol. Boron-polyol complexes may provide a mechanism for mobilizing B in these species. To determine the long-term effects of applied B, seedlings were grown for two growing seasons after the application of 10B to shoots. In Norway spruce, the proportion of 10B in the root systems and current needles of the harvest year was slightly higher than in the controls, and in Scots pine root systems, marginally so. The B treatment had no effect on growth of Norway spruce seedlings. In Scots pine seedlings, the B treatment caused a 33% increase in total dry mass and significantly increased the number of side branches. 相似文献
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Lavola A 《Tree physiology》1998,18(1):53-58
A growth chamber experiment was conducted to examine the effects of UV-B exposure (4.9 kJ m(-2) day(-1) of biologically effective UV-B, 280-320 nm) on shoot growth and secondary metabolite production in Betula pendula (Roth) and B. resinifera (Britt.) seedlings originating from environments in Finland, Germany and Alaska differing in solar UV-B radiation and climate. Neither shoot growth nor the composition of secondary metabolites was affected by UV-B irradiance, but the treatment induced significant changes in the amounts of individual secondary metabolites in leaves. Leaves of seedlings exposed to UV-B radiation contained higher concentrations of several flavonoids, condensed tannins and some hydroxycinnamic acids than leaves of control seedlings that received no UV-B radiation. At the population level, there was considerable variation in secondary metabolite responses to UV-B radiation: among populations, the induced response was most prominent in Alaskan populations, which were adapted to the lowest ambient UV-B radiation environment. I conclude that solar UV-B radiation plays an important role in the formation of secondary chemical characteristics in birch trees. 相似文献
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Seedlings of closely related birch species Betula pendula and B. resinifera, which have moderate similarity in their phytochemical composition, were exposed to a SO2 concentration of 200 μg m-3 for 24 days to detect their sensitivity and possible induced changes in the amount of primary and secondary phytochemicals. The species deviated from each other in the production of biomass and phytochemicals. The SO2 pollution induced no changes in growth nor in the soluble sugar concentrations in the species. However, the chromatographic analyses showed the moderate reduction in the amount of antioxidative and defensive phenolics, i.e. myricitrin, (+)-catechin, 3,4'-dihydroxypropiophenone and proanthocyanidins in both birch species. These results indicate more pronounced sensitivity of secondary metabolism to SO2 pollution compared with primary metabolism, and the reduced tolerance of birches to other oxidative air pollutants as well as to herbivores in polluted environments. 相似文献
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Lavola A Karjalainen R Julkunen-Tiitto R 《Journal of agricultural and food chemistry》2012,60(4):1020-1027
The Saskatoon berry is currently cultivated in many parts of the world for its suitability for various food products and due to its high content of nutrients and polyphenols. To determine the phytochemical profile of a Saskatoon plant, polyphenols from leaves, stems, and berries were screened from four cultivars grown in Finland using HPLC-DAD and HPLC-ESI/MS. The phenolic composition and concentrations varied among plant parts and cultivars. The main berry components were cyanidin-based anthocyanins (63% of the phenols), quercetin-derived flavonol glycosides, and hydroxycinnamic acids. The total anthocyanin content varied between 258.7 and 517.9 mg/100 fresh weight among cultivars. Protocatechuic acid was found for the first time in Saskatoon berries. The leaves consisted of quercetin- and kaempferol-derived glycosides (41% of the phenols), hydroxycinnamic acids (36%), catechins, and some neolignans. Quercetin 3-galactoside and 3-glucoside, (-)-epicatechin, and chlorogenic acid were the main phenolics in the leaves of all cultivars. The stem components were flavanone and flavonol glycosides (55% of the phenols), catechins (38%), and hydroxybenzoic acids. Concentrations of the main compound, eriodictyol 7-glucoside, varied among cultivars from 3.3 to 6.5 mg/g of stem dry weight. Very high proanthocyanidin contents were found in stems and leaves (10-14% of dry biomass), whereas berries contained a low amount of proanthocyanidins (3% of dry biomass). The findings reveal that leaves and stems of Saskatoon cultivars possess high amounts of various phenolic compounds that may offer new functional raw materials for a wide range of food and health products. 相似文献
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The effect of a moderate increase in atmospheric sulphur dioxide on the production of phenolic secondary chemicals, soluble sugars and phytomass distribution within plants was investigated in six willow (Salix myrsinifolia Salisb.) clones. The plants were cultivated for 3 weeks under 0.11 ppm of SO2 (300 μg m?3). The production of salicin and chlorogenic acid was significantly reduced under increased SO2. However, salicortin, 2′-O-acetylsalicortin, (+)-catechin and two unknown phenolics did not show any clear trend. The increase in SO2 did not affect the glucose, fructose and sucrose contents. The final weight of the SO2-treatment plants was significantly greater than that of the control plants: the leaf, stem and root phytomass was from 14 to 48% greater under increased SO2. All the clones showed the same trend, although there was a significant variation in phytomass production. Our results indicate, although not consistently that even a short-term exposure of enhanced atmospheric SO2 may change moderately the accumulation pattern of willow phenolics. 相似文献
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