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1.
Masahiro Yamaguchi Makoto Watanabe Mayumi Iwasaki Chikako Tabe Hideyuki Matsumura Yoshihisa Kohno Takeshi Izuta 《Trees - Structure and Function》2007,21(6):707-718
To obtain the basic data for evaluating the critical level of ozone (O3) to protect Japanese deciduous broad-leaved forest tree species, the growth and photosynthetic responses of Fagus crenata seedlings to O3 under different nitrogen (N) loads were investigated. The seedlings were grown in potted andisol supplied with N as NH4NO3 solution at 0, 20 or 50 kg ha−1 year−1 and were exposed to charcoal-filtered air or O3 at 1.0, 1.5 and 2.0 times the ambient concentration for two growing seasons. The interactive effect of O3 and N load on the whole-plant dry mass of the seedlings at the end of the second growing season was significant. The O3-induced reduction in the whole-plant dry mass of the seedlings was greater in the relatively high N treatment than that in
the low N treatment. This interactive effect was mainly due to the difference in the degree of O3-induced reduction in net photosynthesis among the N treatments. The degree of O3-induced reduction in N availability to photosynthesis was greater in the relatively high N treatment than that in the low
N treatment. In conclusion, the sensitivity of growth and photosynthetic parameters of F. crenata seedlings to O3 become high with increasing amounts of N added to the soil. Therefore, N deposition from the atmosphere should be taken into
account to evaluate the critical level of O3 to protect Japanese deciduous broad-leaved forest tree species. 相似文献
2.
We examined the carry-over effects of ozone (O3) and/or water stress on leaf phenological characteristics and bud frost hardiness of Fagus crenata seedlings. Three-year-old seedlings were exposed to charcoal-filtered air or 60 nl l–1 O3, 7 h a day, from May to October 1999 in naturally-lit growth chambers. Half of the seedlings in each gas treatment received 250 ml of water at 3-day intervals (well-watered treatment), while the rest received 175 ml of water at the same intervals (water-stressed treatment). All the seedlings were moved from the growth chambers to an experimental field on October 1999, and grown until April 2000 under field conditions. The exposure to O3 during the growing season induced early leaf fall and reduction in leaf non-structural carbohydrates concentrations in the early autumn, as well as resulting in late bud break and reduction in the number of leaves per bud in the following spring. However, O3 did not affect bud frost hardiness in the following winter. On the contrary, water stress did not affect leaf phenological characteristics, leaf and bud non-structural carbohydrates concentrations and bud frost hardiness. There were no significant synergistic or antagonistic effects of O3 and water stress on leaf phenological characteristics, concentrations of leaf and bud non-structural carbohydrates and bud frost hardiness of the seedlings. These results show that the carry-over effects of O3 can be found on the phenological characteristics and leaf non-structural carbohydrates concentrations, although there are almost no carry-over effects of water stress on phenological characteristics and winter hardiness of the seedlings. 相似文献
3.
Kun-dong Bai De-bao Liao De-bing Jiang Kun-fang Cao 《Trees - Structure and Function》2008,22(4):449-462
Photosynthetic induction times and photoinhibition in relation to simulated sunflecks (sudden increase of irradiance from
20 to 1,500 μmol m−2 s−1) were examined in leaves of co-occurring Fagus lucida (a deciduous tree) and Castanopsis lamontii (an evergreen tree) saplings grown either in a beech forest understory or in an adjacent open site during a late rainy season.
Two hypotheses were tested: (1) understory leaves would display faster photosynthetic induction times and greater photoinhibition
than open-grown leaves; and (2) evergreen species would have slower photosynthetic induction times and lighter photoinhibition
than deciduous species. Times to reach 90% of maximal CO2 assimilation rate (t
90%A
) and stomatal conductance
did not differ between species, but showed faster by 3–5 min in open-grown leaves than understory leaves due to higher initial
stomatal conductance (g
s
initial) and induction state 1 min into simulated sunflecks (IS1min) in the former. Our analysis across the published data on photosynthetic induction of 48 broad-leaved woody species again
revealed the negative correlations between t
90%A
and either g
s initial or IS1min, and the similarity of t
90%A
and between evergreen and deciduous species. Measurements of maximum PSII photochemical efficiency (F
v/F
m) indicated that photoinhibition occurred in saplings in any of the growth habitats during sunfleck-induced photosynthetic
induction. Despite no interspecific differences in the degree of photoinhibition, understory leaves of both species suffered
heavier photoinhibition than open-grown leaves, as indicated by a stronger decrease of F
v/F
m in the former. Dynamic changes in the quantum yields of PSII photochemistry and ΔpH- and xanthophyll-regulated thermal dissipation
and adjustments in the partitioning of electron flow between assimilative and non-assimilative processes were functional to
resist photoinhibition. However, such photoinhibition, together with stomatal and biochemical limitations, would decrease
carbon gain during simulated sunflecks, particularly in understory leaves. 相似文献
4.
Orobanche crenata Forsk is a chlorophyll lacking holoparasite that subsists on the roots of plants and causes significant damage to the culture
of leguminous plants and, in particular, to peas (Pisum sativum L.). Here, we investigated the potential of Rhizobium strains for biological control of Orobanche crenata using a commercial pea cultivar (Douce de province) and different Rhizobium strains. Firstly, benefit of bacterial inoculation on plant growth and efficiency in N-incorporation were demonstrated with
four isolates, P.SOM, P.1001, P.Mat.95 and P.1236. After five Rhizobium strains (three efficient: P.SOM, P.1236, P.Mat.95 and two not efficient: P.OM1.92, P.MleTem.92) were investigated for their
ability to control Orobanche crenata using pot and Petri dish experiments. Inoculation of peas with two (P.SOM and P.1236) of the five strains induced a significant
decrease in O. crenata seed germination and in the number of tubercles on pea roots. Furthermore, other symptoms, including the non-penetration
of the germinated seeds into pea roots followed by radicle browning and death of the parasites, were observed in the presence
of these inoculated pea plants. The hypothesis that roots secrete toxic compounds related to Rhizobium inoculation is discussed. 相似文献
5.
The seasonal occurrence of Mycosphaerella buna in leaves and contiguous organs of Fagus crenata was studied in a Japanese beech forest, Ibaraki, Japan, in 1998 and 1999. Mycosphaerella buna was not isolated from newly developed leaves in May, but it was isolated from asymptomatic leaves after June. The frequency of its occurrence gradually increased until leaffall. In contrast, M. buna was not isolated from overwintered buds, leaf petioles, or contiguous current-year twigs. The spermogonia and pseudothecia were observed in dead leaves after leaffall. The mature pseudothecia were found on dead leaves from May to July. The ascospores produced in the pseudothecia were suggested to infect newly developed leaves.Contribution no. 173, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan 相似文献
6.
Nitraria retusa and Atriplex halimus (xero-halophytes) plants were grown in the range 0–800 mM NaCl while Medicago arborea (glycophyte) in 0–300 mM NaCl. Salt stress caused a marked decrease in osmotic potential and a significant accumulation of
Na+ and Cl− in leaves of both species. Moderate salinity had a stimulating effect on growth rate, net CO2 assimilation, transpiration and stomatal conductance for the xero-halophytic species. At higher salinities, these physiological
parameters decreased significantly, and their percentages of reduction were higher in A. halimus than in N. retusa whereas, in M. arborea they decreased linearly with salinity. Nitraria retusa PSII photochemistry and carotenoid content were unaffected by salinity, but a reduction in chlorophyll content was observed
at 800 mM NaCl. Similar results were found in A. halimus, but with a decrease in the efficiency of PSII (F′v/F′m) occurred at 800 mM. Conversely, in M. arborea plants we observed a significant reduction in pigment concentrations and chlorophyll fluorescence parameters. The marked
toxic effect of Na+ and/or Cl− observed in M. arborea indicates that salt damage effect could be attributed to ions’ toxicity, and that the reduction in photosynthesis is most
probably due to damages in the photosynthetic apparatus rather than factors affecting stomatal closure. For the two halophyte
species, it appears that there is occurrence of co-limitation of photosynthesis by stomatal and non-stomatal factors. Our
results suggest that both N. retusa and A. halimus show high tolerance to both high salinity and photoinhibition while M. arborea was considered as a slightly salt tolerant species. 相似文献
7.
To obtain basic information for evaluating critical loads of acid deposition for protecting Japanese beech forests, growth, net photosynthesis and leaf nutrient status of Fagus crenata seedlings grown for two growing seasons in brown forest soil acidified with H2SO4 or HNO3 solution were investigated. The whole-plant dry mass of the seedlings grown in the soil acidified by the addition of H2SO4 or HNO3 solution was significantly less than that of the seedlings grown in the control soil not supplemented with H+ as H2SO4 or HNO3 solution. However, the degrees of reduction in the whole-plant dry mass and net photosynthetic rate of the seedlings grown in the soil acidified by the addition of H+ as H2SO4 solution at 100 mg l–1 on the basis of air-dried soil volume (S-100 treatment) were greater than those of the seedlings grown in the soil acidified by the addition of H+ as HNO3 solution at 100 mg l–1 (N-100 treatment). The concentrations of Al and Mn in the leaves of the seedlings grown in the S-100 treatment were significantly higher than those in the N-100 treatment. A positive correlation was obtained between the molar ratio of (Ca+Mg+K)/(Al+Mn) in the soil solution and the relative whole-plant dry mass of the seedlings grown in the acidified soils to that of the seedlings grown in the control soil. Based on the results, we concluded that the negative effects of soil acidification due to sulfate deposition are greater than those of soil acidification due to nitrate deposition on growth, net photosynthesis and leaf nutrient status of F. crenata, and that the molar ratio of (Ca+Mg+K)/(Al+Mn) in soil solution is a suitable soil parameter for evaluating critical loads of acid deposition in efforts to protect F. crenata forests in Japan. 相似文献
8.
Abstract Gas exchange and growth of beech seedlings planted in the understory of a recently thinned pinewood were recorded for 2 years. Relative irradiance was assessed by hemispherical photographs taken just after the thinning. Predawn water potential (pd), daily gas exchange and chlorophyll fluorescence were measured several times during the two growing seasons. Maximum values of photosynthesis (A
max) and stomatal conductance to water vapour (g
wvmax) were established from daily data. Maximum quantum efficiency of PS II was recorded at dawn by taking the variable to maximum chlorophyll fluorescence ratio on dark adapted leaves (F
v/F
m). In the middle of each summer, leaf nitrogen content and leaf mass per area were evaluated, and height growth and basal area increment were recorded at the end of the season. The thinning treatment removed half the trees and generated around 10% more available relative irradiance (GLF). This was followed by an increase in net photosynthesis at saturating PPFD (A
sat) and in maximum stomatal conductance to water vapour (g
wvmax). Moreover, specific leaf mass (SLM) and mass based nitrogen content (Nm) showed higher values for seedlings in the thinned stand. In both years, a positive relationship was established between the area based nitrogen content (Na) and maximum net photosynthesis (A
max). In 1998, a year with a dry summer, seedlings suffered a significant drop in daily A
max irrespective of the thinning regime. This was a response to an increase in stomatal limitation to net photosynthesis, g
wvmax reaching the lowest value on dates with the highest drought. A lack of decrease of Fv/Fm confirmed the absence of significant non-stomatal limitation to A as a consequence of photoinhibition after opening the pinewood. A higher maximum quantum efficiency of open PS II centres (Fv/Fm) was registered in seedlings in the thinned stand. The significance of the differences between the treatments was stronger in the second year after thinning. In 1999, a year with frequent summer storms, water availability increased for seedlings growing under the thinned pinewood. Overall, the reduced pine overstory had a positive effect on physiological responses of beech seedlings, which was translated into improved seedling growth. 相似文献
9.
Ardisia crenata, an evergreen shrub native to East Asia, has been a serious invasive plant to the southeastern USA. Here 13 polymorphic microsatellite
loci were isolated and characterized from an enrichment genomic library of A. crenata. The average allele number of these microsatellites was four per locus, ranging from two to seven. The ranges of observed
and expected heterozygosity were 0.000–1.000 and 0.239–0.789, respectively. These microsatellite markers will be useful for
investigating population genetics and reproductive ecology of A. crenata. 相似文献
10.
Salt impact on photosynthesis and leaf ultrastructure of <Emphasis Type="Italic">Aeluropus littoralis</Emphasis> 总被引:1,自引:0,他引:1
The effects of salinity (400 mM NaCl) on growth, biomass partitioning, photosynthesis, and leaf ultrastructure were studied
in hydroponically grown plants of Aeluropus littoralis (Willd) Parl. NaCl produced a significant inhibition of the main growth parameters and a reduction in leaf gas exchange (e.g.
decreased rates of photosynthesis and stomatal conductance). However, NaCl salinity affected neither the composition of photosynthesis
pigments nor leaf water content. The reduction in leaf gas exchange seemed to correlate with a decrease in mesophyll thickness
as well as a severe disorganisation of chloroplast structure, with misshapen chloroplasts and dilated thylakoid membranes.
Conspicuously, mesophyll chloroplasts were more sensitive to salt treatment than those of bundle sheath cells. The effects
of NaCl toxicity on leaf structure and ultrastructure and the associated physiological implications are discussed in relation
to the degree of salt resistance of A. littoralis. 相似文献
11.
We analysed changes in AMP, ADP, and ATP concentrations and adenylate energy charge in Norway maple (Acer platanoides L.) and European beech (Fagus sylvatica L.) seeds during dormancy breaking (at 3 °C) and in the control variant at 15 °C. Values of the studied indicators in stratified
beech seeds were generally higher at 15 °C, at least until germination (+3 °C). By contrast, in maple seeds, the values recorded
during dormancy breaking by cold stratification were much higher than at 15 °C. Three peaks (usually in weeks 3, 6, and 8)
were observed in maple seeds at 3 °C, but not at 15 °C. Among adenine nucleotides, AMP reached the highest levels in both
species in both variants of the experiment. 相似文献
12.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae. 相似文献
13.
Junko Kitagawa Takeshi Nakagawa Masaaki Okuda Masaharu Fukuoka Yoshinori Yasuda 《Economic botany》2008,62(4):594-603
Correcting Misperceptions about the History of
Castanea
Stands in
Satoyama
in Japan. Mistaken ideas about the naturalness of past and present landscapes are widespread in diverse cultures and in the scientific
literature, and many of these ideas are only now being seriously challenged by current research (e.g., Erickson 2006; Fairhead and Leach 1996; Hall 1998; Ramankutty and Foley 1999; Willis et al. 2004). For example, the chestnut, Castanea crenata, has long been an important tree in Japanese culture, which has been cultivated, among other things, for its much loved edible
nut and its valuable timber. Today, the widely-held view in Japan, which also appears in the scholarly and popular literature,
is that in the past Castanea stands covered a large area throughout Japan, and these stands only disappeared because of economic development, especially
in association with railway construction. Otaru, Hokkaido, is one of the places where people believe Castanea stands covered a large area and were deforested only recently. Local people in Otaru believe that the stand in Temiya Park
has existed since the Jomon Period. For a more accurate historical perspective on Japanese forestation, we have performed
pollen analysis to clarify the timing of the introduction of the Castanea tree into Otaru region and to reveal the history of this specific Castanea stand in Temiya Park. The results indicate that Castanea was first found in Otaru region 7100 B.P., but that it was not cultivated extensively until recently. Based on our study,
and on data from this area dating to the late 19th century, we concluded instead that the Castanea stand we studied in Temiya Park, Otaru, was established after the mid-20th century. We believe the results of this study
are applicable to Castanea stands in other parts of Japan as well. 相似文献
14.
A pea rust fungus, Uromyces viciae-fabae, has been classified into two varieties, var. viciae-fabae and var. orobi, based on differences in urediniospore wall thickness and putative host specificity in Japan. In principal component analyses, morphological features of urediniospores and teliospores of 94 rust specimens from Vicia, Lathyrus, and Pisum did not show definite host-specific morphological groups. In molecular analyses, 23 Uromyces specimens from Vicia, Lathyrus, and Pisum formed a single genetic clade based on D1/D2 and ITS regions. Four isolates of U. viciae-fabae from V. cracca and V. unijuga could infect and sporulate on P. sativum. These results suggest that U. viciae-fabae populations on different host plants are not biologically differentiated into groups that can be recognized as varieties.Contribution no. 184, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan 相似文献
15.
Quantitative characteristics of photosynthetic electron transport were evaluated in vivo on the basis of the multi-exponential
analysis of OJIP fluorescence transients induced by saturating actinic light. The OJIP fluorescence curve F(t), measured in Chlamydomonas reinhardtii cells, was transformed into the (1 − F
O/F(t)) × (F
V
/F
M)−1 transient, which is shown to relate to PS 2 closure. We assumed that kinetics of PS 2 closure during OJIP rise reflects time-separated
processes related to the establishment of redox equilibrium at the PS 2 acceptor side (OJ), PQ pool (JI), and beyond Cyt b/f
(IP). Three-exponential fitting was applied to (1 − F
O/F(t)) × (F
V
/F
M)−1 transient to obtain lifetimes and amplitudes of the OJ, JI, and IP components of PS 2 closure, which were used to calculate
overall rates of reduction and re-oxidation of the PS 2 acceptor side, PQ pool, and intermediates beyond Cyt b/f complex.
The results, obtained in the presence of inhibitors, oxidative reagents, and under different stress conditions prove the suggested
model and characterize the introduced parameters as useful indicators of photosynthetic function. 相似文献
16.
Stefanie Kimbacher Ingrid Gerstl Branko Velimirov Sylvia Hagemann 《Molecular genetics and genomics : MGG》2009,282(2):165-172
P transposons belong to the eukaryotic DNA transposons, which are transposed by a cut and paste mechanism using a P-element-coded transposase. They have been detected in Drosophila, and reside as single copies and stable homologous sequences in many vertebrate species. We present the P elements Pcin1, Pcin2 and Pcin3 from Ciona intestinalis, a species of the most primitive chordates, and compare them with those from Ciona savignyi. They showed typical DNA transposon structures, namely terminal inverted repeats and target site duplications. The coding
region of Pcin1 consisted of 13 small exons that could be translated into a P-transposon-homologous protein. C. intestinalis and C. savignyi displayed nearly the same phenotype. However, their P elements were highly divergent and the assumed P transposase from C. intestinalis was more closely related to the transposase from Drosophila melanogaster than to the transposase of C. savignyi. The present study showed that P elements with typical features of transposable DNA elements may be found already at the base of the chordate lineage.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
17.
Notocactus scopa cv. Soonjung was subjected to in planta Agrobacterium tumefaciens-mediated transformation with vacuum infiltration, pin-pricking, and a combination of the two methods. The pin-pricking combined with vacuum infiltration (20-30 cmHg for 15 min) resulted in a transformation efficiency of 67-100%, and the expression of the uidA and nptII genes was detected in transformed cactus. The established in planta transformation technique generated a transgenic cactus with higher transformation efficiency, shortened selection process, and stable gene expression via asexual reproduction. All of the results showed that the in planta transformation method utilized in the current study provided an efficient and time-saving procedure for the delivery of genes into the cactus genome, and that this technique can be applied to other asexually reproducing succulent plant species. 相似文献
18.
We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan. 相似文献
19.
20.
Mycena cupulicola sp. nov. and M. adscendens var. carpophila, new to Japan, are described and illustrated. The former is characterized by having lageniform caulocystidia with a slightly thick-walled broadened base and no cheilocystidia. The latter is characterized by having a white pileus up to 1mm in diameter and narrowly conical caulocystidia. Mycena cryptomeriicola was confirmed to have inamyloid basoidiospores. 相似文献
