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1.
《Scientia Horticulturae》2005,103(4):461-471
In soilless cultures, fertiliser leaching is particularly large in spring, when fertilisation is applied during rainy periods. Therefore, a better knowledge of the N uptake periods and of the amount of N mobilised from the storage organs could improve fertilisation management during spring growth. Nitrogen allocation was studied for two consecutive years in Ligustrum ovalifolium L. These shrubs were cultivated in containers, fertilised (with or without 15N) in spring and autumn of the first year, and received either fertilisation or only tap water on the subsequent spring growth. Nitrogen assimilated in spring was preferentially allocated to the leaves whereas a large part of N assimilated in autumn was directly stored in the perennial organs, mainly in roots. During the subsequent spring period, N was mobilised from all perennial organs, with a proximity gradient, to sustain bud break and shoot growth. Nitrogen assimilated in autumn was preferentially used to sustain shoot growth, with a rate of 68% of its winter N content against 55% for N assimilated the previous spring. When plants were subjected to spring fertilisation, growth was initially sustained by N mobilisation before N assimilation resumption, but N mobilisation was 15% lower than in unfertilised plants. Overall results are discussed in terms of the improvement of the N-fertilisation efficiency relative to spring growth of ornamental shrubs cultivated in container.  相似文献   

2.
Summary

The comparative effects of partial root-zone irrigation (PRI) and deficit irrigation (DI) on phosphorus (P) uptake in tomato (Lycopersicon esculentum Mill.) plants were investigated in a split-root pot experiment. The results showed that PRI treatment improved water-use efficiency (WUE) compared to the DI treatment. PRI-treated plants accumulated significantly higher amounts of P in their shoots than DI plants under organic maize straw N fertilisation, whereas similar levels of shoot P accumulation were observed under mineral N fertilisation. Thus, the form of N fertiliser, and thereby the different plant N status, affected the accumulation of P in shoots, as reflected by a higher plant N:P ratio following mineral N fertilisation than after organic N fertilisation. Compared to the DI treatment, PRI significantly increased both the physiological and agronomic efficiencies of P-use under mineral N fertilisation, while similar physiological and agronomic P-use efficiencies were found between the two irrigation treatments with organic N fertilisation. PRI-induced drying and wetting processes might have influenced the bio-availability of soil P, as the concentrations of bio-available P in both bulk and rhizosphere soils were increased compared with the DI treatment under both forms of N fertilisation. It is suggested that a relatively high soil water content in the wet zone of the PRI treatment should be maintained in order to facilitate nutrient (i.e., N and P) transport from the bulk soil to the root surface, thereby enhancing nutrient uptake by the roots.  相似文献   

3.
The root extension rate of Betula pendula, transplanted at two phenological stages, was studied in a Nordic climate. Landscape-size trees were transplanted from the field into root-study boxes (rhizotron) in early and late spring of 1999 and 2000. In early spring, 6 trees were transplanted when the leaves had just started to unfold; likewise, in late spring, six trees were transplanted when the leaves were fully unfolded and the shoot extension was in progress. Root growth was recorded during the first post-transplant season and the tree roots were finally excavated. Results indicate that the root extension rate of B. pendula follows seasonal soil temperature. The mean root extension rates at ten days intervals varied from 4 to 11 mm/day with a total average for the growing season of 7 mm/day in 1999 and varied from 4 to 9 mm/day with a total average for the growing season of 4 mm/day for 2000. The average length of new roots was 89 cm and there was no significant difference in length, dry weight or number of new roots between the two transplant times. It appears, therefore, that the phenological stage at transplanting during the period from bud break to fully developed leaves has minor effect on landscape establishment of B. pendula, when an adequate amount of water is provided.  相似文献   

4.
The objective of this PhD project was to investigate the nutrient translocation associated with the mulch from the grass alley to the tree strip. Therefore, a historical, approved 40-year fertiliser trial with apple cv. ‘Gloster’ on M9 rootstock at a spacing of 4 m?×?1.5?m was employed at Klein-Altendorf Research Centre, University of Bonn, Germany, which comprised mineral nutrition (1?t/ha??CaO? $ + $ ?NPK), an organic plot (10?t??FM/ha pig manure) and an unfertilised plot as control. Grass alleys were mowed 5?× in 1995 and 3?× in 1996 as commonly practised in fruit orchards; foil was spread on the tree strips to capture the biomass transferred with the mulching. Overall, ca.??60% of the grass mulch dry matter (mowed at 2?cm height) remained in the grass alleyway, while ca.??40% was translocated to the tree strips, which amounted to 550?kg??DM (Dry Matter) in the unfertilised plot and 800?kg??DM/ha/year in both fertilised plots with the five mulches in the wet year 1995. Grass mulch contained 2–3%??N and 2.2–2.9%??K in the unfertilised control plot or 2.1–3.9%??N and 2.7–4.1%??K on per leaf dry matter in both the inorganic NPK and organically fertilised plot; the nitrogen content of the grass mulch increased during the growing season in the wet year 1995, but remained low and constant at 2.5%??N in the dry year 1996. By contrast, calcium was decreased from 0.5–0.7%??Ca in the unfertilised plot to 0.3–0.6%??Ca in the organic plot. Overall, 25–50% of the grass mulch was translocated from the grass alleys (ca. 4,000 m2) into the tree strips, representing an organic fertilisation of 10–25?kg??N, 2–4?kg??P, 15–25?kg??K, 3–5?kg??Ca and 1–2?kg??Mg per hectare and year. This would theoretically be equivalent to ca 50% supply of??N,??P and??K and??10% of calcium as required nutrients by fruit trees depending on rate of nutrient availability. Its subsequent partial availability reported of 54%??N within??90 days after mulching and large nutrient content are discussed with respect to the low nutrient content in leaves dropped from the fruit trees in the autumn, where the nutrients had been previously translocated into the woody perennial parts of the tree. This nutrient cycling should be integrated in environmental-friendly sustainable fertilisation strategies for fruit orchards.  相似文献   

5.
Summary

Papaya (Carica papaya L.) cv. Coorg Honey Dew is one of the most popular cultivars grown in Southern India, but it requires high doses of inorganic phosphorus (P) fertilisation for growth. Arbuscular mycorrhizal fungi (AMF) are known to improve plant growth and nutrient uptake, especially the uptake of P and micronutrients. As papaya plants respond well to high levels of P, inoculation with AMF was studied to see if AMF could fulfill the requirement for P in plants grown under field conditions. Papaya seedlings (n = 36 per AMF) were colonised separately, in polybags, for 45 d by two species of AMF, Glomus mosseae and G. fasciculatum. Seedlings were then transplanted to the field, with uninoculated seedlings as controls, in a replicated randomised block design. Three levels of P were applied [50, 75, or 100% of the recommended dose (240 g plant–1 year–1) of P fertiliser, as super-phosphate]. Plants were studied for root colonisation by AMF, for growth parameters, and for leaf nutrient contents (especially, P, Zn, and Cu). Acidic and alkaline phosphatase activities in the roots of AMF-colonised plants were recorded as these enzymes are involved in the mobilisation of P. The yields of plants up to 18 months-old, and fruit quality, measured by total soluble solids contents (TSSC) and β-carotene contents, were recorded. AMF-inoculated plants performed better than uninoculated control plants at all levels of P applied. G. mosseae was more effective at improving plant growth, fruit yield, and P and Zn contents than G. fasciculatum at the 75% and 50% P-levels. Cu contents increased at all P-levels in G. fasciculatum-colonised plants. Total soluble solids contents showed marginal improvements at the 75% P level with both fungi. β-carotene contents increased significantly in G. mosseae-colonised plants at the 50% and 75% P-levels, and in G. fasciculatum-colonised plants at the 75% P-level. The feasibility of applying on-farm produced AMF inoculum to improve papaya cultivation and to save 25% of the P applied during papaya cultivation is discussed.  相似文献   

6.
 以盆栽不饱满芽（春梢基部芽）、次饱满芽（秋梢芽）和饱满芽（春梢中部芽）‘嘎啦’苹 果（Malus × domestica‘Gala’）/八棱海棠（Malus micromalus Makino）嫁接幼苗为试材,采用15N、13C 双标记法,研究了其碳、氮营养分配特性。结果表明,新梢开始旺长期叶片13C 分配率不饱满芽幼苗 > 次 饱满芽幼苗 > 饱满芽幼苗,分别为45.81%、42.49%、35.05%;根部13C 分配率饱满芽幼苗 > 次饱满芽 幼苗 > 不饱满芽幼苗,分别为20.04%、15.88%、12.67%。新梢旺长期3 种芽幼苗叶片、根部13C 分配率 趋势与新梢开始旺长期相反。新梢缓长期各芽苗叶片碳同化物分配差异不显著,根部13C 分配率,次饱满 芽幼苗和不饱满芽幼苗显著高于饱满芽幼苗。叶片15N 分配率逐渐升高,始终为饱满芽幼苗 > 次饱满芽 幼苗 > 不饱满芽幼苗,至新梢缓长期分别达到55.67%、52.45%和51.54%。根部15N 分配率随生长发育 而降低,新梢开始旺长期和新梢旺长期不饱满芽幼苗 > 次饱满芽幼苗 > 饱满芽幼苗。新梢缓长期各器 官氮素分配率差异不显著。不同芽幼苗13C 固定量、15N 利用率均逐渐升高并趋于一致,表明芽有同等更 新潜质。  相似文献   

7.
碳酸氢根和铵态氮共同对菜豆生长及养分吸收的影响   总被引：5，自引：1，他引：5  
 以菜豆为材料进行水培试验, 探讨了高浓度NH4+-N与HCO3-共存介质对菜豆生长发育及其营养吸收的影响, 结果表明: ①以HCO3--N 为主要氮源时, 菜豆生长状况最好; 以NH4+-N为主要氮源且无HCO3-存在时, 培养前期菜豆根系就发生受害现象, 叶片出现萎蔫; 但加入HCO3-后, 随着营养液中HCO3- 浓度从0 升高到13. 0 mmol/L , 菜豆长势逐渐改善, 表明HCO3-与NH4+ 以较合适的比例共存于介质中可明显减轻二者非共存对菜豆生长的抑制作用。② 同一处理, 菜豆整株对主要营养元素吸收量的次序为: N > K> P > Ca >Mg > Fe >Mn , 以NH4+2N 为主要氮源时, 随HCO3-浓度升高, 菜豆对N、P、Ca、Mn 的吸收量逐渐增大。③以NO3--N 为主要氮源, P、Fe、Mn 元素在根部出现累积, 而以NH4+-N为主要氮源时, 随HCO3-浓度增加, N、P、Ca、Mn 在根部亦有累积现象。  相似文献   

8.
以番茄(Solanum lycopericum)超表达桃SnRK1(蔗糖非发酵蛋白激酶–1)基因PpSnRK1α的株系及野生型为试材,研究在养分供应不足时SnRK1对植株生长的影响。结果表明,低营养条件下,转基因番茄叶片和根系中的Sn RK1酶活性比野生型高41.55%和39.46%;功能叶片的净光合速率平均比野生型高18.98%;低营养胁迫12 d的叶片SOD、POD、CAT活性比野生型高35.56%、28.85%和14.90%;根系活力比野生型高26.39%;茎和叶中氮磷含量显著高于野生型,钾含量两者差别不大,在根系中氮磷含量差别不大,而钾含量显著高于野生型,且氮素向地上部茎和叶中的分配比率增加。上述结果说明,在营养缺乏条件下,超表达PpSnRK1α可以提高番茄功能叶净光合速率,促进植株对氮素的吸收利用,从而延缓叶片衰老。  相似文献   

9.
We stored plug seedlings of tomato (Solanum lycopersicum L. cv. Momotaro) under limited fertilisation (LF) for 12 weeks, and evaluated growth and development during storage and after planting. Seedlings in the LF treatment were grown in substrate containing starter fertiliser and irrigated with water. Controls (CT) were irrigated with nutrient solution. Stem growth, leaf growth, and biomass accumulation slowed or ceased during storage of LF seedlings, while CT seedlings showed increases in these parameters. At 2 weeks after planting, the stem length of LF seedlings was shorter than that of CT seedlings, but the two seedling types had similar numbers of leaves. At harvest, LF and CT plants had similar numbers of leaves under the fruit trusses, but the trusses formed at lower heights in LF than in CT seedlings. LF and CT plants produced similar numbers of fruits and similar yields from the first to third trusses. These results indicate that tomato plug seedlings can be stored for more than 2 months under LF.  相似文献   

10.
The raspberry moth causes serious damage to cultivated raspberries during certain years, particularly in the Scottish fruit-growing areas where it is a major pest. In the south of England it is less abundant, although in recent years there have been indications that it may become more widespread and plentiful there (Massee, 1939, 1942, 1946).

The female moth lays eggs during June and July in the fleshy tissue at the base of the corolla and androecium. The larva, on hatching from the egg, feeds for a short time on the surface tissue of the developing fruitlet, but within a few days it penetrates into the fruit to feed on the fleshy receptacle. During this period it casts its skin once. From the fruit the second instar larva migrates in search of a place in which to hibernate. Hibernacula appear to be situated mostly in the soil close to the roots of the raspberry plants. Prior to hibernation taking place, the larva moults for the second time, so that it passes the winter as a third instar larva.

With the approach of spring, at the time when the raspberry buds are bursting, the larva leaves its hibernaculum and crawls up a cane until it finds a suitable bud into which it eats a tunnel through the closely packed leaflets. Sometimes a larva, after having consumed the contents of its first bud, leaves it and attacks a second bud which, by this time, may have developed into a young lateral two to three inches long. The larva, which infests a single bud during its spring life, pupates in that bud, but that which infests more than one bud pupates on tie-wires, leaves, canes, supporting posts or similar places. During its spring life the larva passes through another two instars (the fourth and fifth) before pupating.

The full-grown larva prepares for pupation by spinning a white silk cocoon in some suitable place. This takes approximately five days to complete. Within the cocoon the larva pupates and the pupa remains for a period of three weeks.

Adult moths appear in June and are abundant during the second half of the month. Egg- laying then commences and a new generation of the species begins.

The summer larvae, which hatch during July from eggs laid in the flowers by the female moths, do little damage to the fruit because they are very small and their feeding is largely confined to the receptacle tissue.

The most serious damage is perpetrated by the larvae which emerge from hibernation in early spring and bore into the developing buds and laterals. Although their primary buds are killed by the caterpillars these are usually replaced by secondary buds; if these in their turn are largely destroyed by migrating caterpillars the plant’s recovery is prevented because there are no further replacements to overcome the second wave of attack.  相似文献   

11.
 以童期不同的海棠（Malus sp.）植株为试材,使用酶联免疫法（ELISA）测定花芽分化期间 短枝顶芽、幼叶、细根中内源激素含量的变化,以探讨内源激素对花芽分化的影响,为缩短果树童期、 开发利用早实海棠资源奠定基础。结果显示,早实植株与成熟嫁接植株的内源激素含量变化趋势相似。 花芽分化的前期阶段,芽和根中IAA 含量均逐渐减少,到9 月初开始上升,成熟植株含量整体低于未成 熟植株;成熟植株叶中内源IAA 含量高于未成熟植株。芽中GAs 先上升后下降再上升,成熟植株8 月份 达到最低,而未成熟植株9 月份处于最低水平;叶中GAs 含量在成熟植株均保持较低水平;根中GAs 变 化与芽相反。内源ZR 含量在不同器官均有大幅增加,成熟植株均高于未成熟植株,实生早实植株中的变 化幅度最大。成熟植株芽中ABA 含量在160 ~ 170 ng · g-1FW 上下波动,未成熟植株始终低于160 ng · g-1FW;叶和根中的ABA 含量变化趋势一致,即先升高后逐渐下降,9 月之后回升。成熟植株较未成 熟植株在芽与叶中均表现为高比值的ABA/GAs 与ZR/GAs,而根中与此相反。  相似文献   

12.
Fertilizer nitrogen was applied to pot-grown trees during the year of initial scion growth either as “spring N”, “summer N” or “autumn N”, while other trees were left untreated—“minus N”. Tree performance was followed until fruit set the following summer.

At regular intervals whole trees were sampled, divided into as many as seven different parts, which were separately weighed, dried and analysed for total nitrogen. Specimens were also taken for histological examination of flower bud development.

The large amount of fertilizer given as “spring N” resulted in extensive root damage from which the trees did not recover fully; nevertheless they produced large, vigorous scions. After “spring N” and “summer N” at lower dosages the total N content of all parts increased substantially and rapidly. “Autumn N” was absorbed more slowly and remained largely in the roots during the winter, when a considerable amount of root growth took place.

Flowers were initiated in late July or early August on all trees except those given “spring N”, on which flower primordia were not initiated until September. The development of flower buds was accelerated during September on “summer N” trees compared with those left untreated. From the end of November until the end of March no further differentiation took place on “minus N” or “spring N” trees, but it continued on the other treatments, especially following “autumn N”.

“Summer N” and “autumn N” trees were 4–5 days in advance of the others in flowering. “Summer N” trees had large flowers and large green primary leaves, whereas those on “autumn N” trees were smaller and the leaves were initially pale, though turning dark green during blossoming.

When the blossoms were self-pollinated under controlled conditions virtually no fruit was set on “minus N” and “spring N” trees, but “summer N” gave an appreciable set and “autumn N” a heavy set. Only the “summer N” and ”autumn N” flowers had ovules that remained viable six days after anthesis, which was the minimum period found necessary for the pollen tubes to effect fertilization.

It is suggested that fertilizer nitrogen stimulates the synthesis of a kinin-like factor in the roots and that the difference in response to applications at different times of year depends upon the stage of development of the flower buds when this factor reaches them.  相似文献   

13.
The effect of scion on Cl and Na accumulation and the transport properties of rootstocks was investigated using grafted plants. The combinations of Navel orange (C. sinensis (L.) Osb.) and Clementine (C. clementine Hort. ex Tan) scions on Cleopatra mandarin (C. reticulata Blanco) and Troyer citrange (C. sinensis X P. trifoliata) rootstocks, were used in all experiments. Plants were grown under glasshouse conditions for 14 weeks supplied with nutrient solution containing 0-60 mM NaCl. Relative growth and defoliation were studied. The reduction in relative growth caused by salt, treatments was more scion- dependent, whereas defoliation was more rootstock-dependent. Changes in leaf and root ionic contents were measured. Scions on Cleopatra mandarin accumulated less Cl in their leaves and roots than did scions on Troyer citrange. The distribution of Cl in the whole plant showed that Clementine had a reduced ability to transport Cl from roots to leaves. However, sodium content was lower in scions on Troyer citrange than Cleopatra mandarin. The distribution of Na in the whole plant showed that Troyer citrange restricted the transport of Na to the scion. There was little difference in P content in all combinations. Salinity decreased sharply the N content of leaves and roots in plants on Troyer citrange, but there was only a slight effect in plants on Cleopatra mandarin. The pattern of N accumulation was inversely correlated with the pattern of Cl accumulation. Salinity decreased K, Ca and Mg contents in leaves and roots of all combinations.  相似文献   

14.
Summary

One-year-old rhododendron (Rhododendron ‘H-1 P.J.M’) and azalea (Rhododendron ‘Cannon’s Double’) plants grown at different nitrogen (N) fertilisation rates were used to assess the influence of soil N applications during the growing season, and foliar applications of urea in the Autumn, on N uptake and accumulation, and plant growth in the following Spring. N uptake efficiency declined linearly during the first growing season with an increasing rate of N fertilisation. For both cultivars, foliar urea application in the Autumn significantly increased plant N content without affecting plant size, regardless of plant N status. Leaves of rhododendron accumulated more N than other plant structures. Plants sprayed with foliar urea in the Autumn had more new growth the following Spring than plants receiving no urea, regardless of whether the plants received fertiliser in the Spring. For azalea, N uptake in the Spring was, in general, not affected by applications of urea during the previous year. For rhododendron, urea application in the Autumn decreased N uptake the following Spring. For both cultivars, increasing N availability during the growing season increased the ratio of above-ground to below-ground dry weight. Our results suggest that combining optimum N applications during the growing season with foliar application of urea in the Autumn can improve N uptake efficiency, increase N storage, and optimise growth in Rhododendron.  相似文献   

15.
Summary

This study addresses vegetative growth and the uptake of nutrients and their accumulation in the vegetative and reproductive tissues of pepino (Solanum muricatum Ait.). The study was conducted in soilless plastic house conditions, with a planting density equivalent to 25.000 plants ha–1 during two seasons (1997–98 and 1998–99). The plants were sampled, fractionated into leaves, stems, fruits and roots, then dried and weighed and the macronutrient content was analysed every 30.d for 300.d after transplanting. The yield obtained was 2.kg of fruit per plant, which is 30% of the total dry weight. The relative growth rate (RGR) ranged from 0.0028 to 0.0451.d–1. The highest N, K, Ca and Mg concentrations were recorded in the leaves, and the highest P concentration in the roots. The nutrient accumulation of this yield was 10.64, 1.12, 16.06, 10.0 and 1.58.g of N, P, K, Ca and Mg per plant respectively. The highest accumulation of all nutrients was found in the leaves. The nutrient with the highest specificuptake rate was K, which ranged from 0.0037 to 0.0838.g g–1 d–1.  相似文献   

16.
The effect of different fertilisation (i.e. broadcast application and fertigation) and irrigation practices (tank sprinkler and drip irrigation) on yield, yield quality (nitrate content), nitrogen uptake of white cabbage (Brassica oleracea var. capitata L.) and the potential for N losses was assessed on sandy-loam agricultural soil. 15N-labelled fertiliser was used as a tracer. It was found that different practices significantly affected yield, nitrate content in plants, N uptake, as well as fertiliser use efficiency. The highest yield (93 t ha−1), plant N uptake (246 kg ha−1), and fertiliser use efficiency (42%) were obtained under treatment with broadcast fertilisation with farmer's practice of irrigation (tank sprinkler). The N surplus after harvest was −41 kg N ha−1, indicating the lowest potential for N losses. Treatment by fertigation and drip irrigation covering 100% of the crop's water requirements did not result in the highest yield as expected (72 t ha−1), the N surplus after harvest was about +38 kg ha−1. The lowest yield (58 t ha−1), fertiliser use efficiency (30%) and hence the highest potential for N losses (N surplus after harvest +68 kg ha−1) were found in treatment with broadcast fertilisation and drip irrigation covering 50% of the crop's water requirements.  相似文献   

17.
‘沁园樱’是由‘染井吉野樱’（Cerasus yedoensis‘Somei-yoshino’）芽变选育而来的樱花新品种。落叶乔木,在长沙地区11 月落叶。成熟叶长椭圆形,纸质,叶正面有茸毛,叶柄上有白色茸毛,上端常有2 腺体。先花后叶,始花期3 月中下旬,终花期3 月底到4 月初,花瓣为5 片,呈卵圆形。  相似文献   

18.
桃及其近缘种花芽分化特性的比较   总被引：3，自引：0，他引：3  
王珂  李靖  王力荣  黎明  方庆 《果树学报》2006,23(6):809-813
以甘肃桃(甘肃桃1号)(Prunuskansuensis)、新疆桃(喀什2号)(P.ferganensis)、普通桃(青丝)(P.persica)为试材,研究了他们的花芽分化特性。结果表明,甘肃桃、新疆桃和普通桃花芽分化顺序一致,都是按花芽分化始期、萼片原基、花瓣原基、雄蕊原基、雌蕊原基这个顺序分化的,但花芽分化各阶段所持续的时间各不相同。甘肃桃、新疆桃和普通桃花芽分化始期不同。甘肃桃花芽分化始期较早,在6月上、中旬已经开始分化,而新疆桃、普通桃则在6月下旬到7月上旬才开始分化。甘肃桃与新疆桃、普通桃雌配子体发育存在差异,甘肃桃形成胚珠原基后越冬,而新疆桃、普通桃则以子房阶段越冬,春季才形成胚珠原基。  相似文献   

19.
Cuttings from 2 cultivars of Cornus alba propagated in late September produced more and longer roots in long days (LD) than in natural days (ND). The effects of photoperiod on rooting were much less when cuttings were propagated in mid-August. LD during propagation in mid-August delayed the onset of leaf senescence and bud dormancy so that heavier and taller plants were obtained. Bud dormancy did not develop if the plants were grown under LD throughout the winter. Such treatment produced very tall plants and resulted in a greater proportion of their dry matter being distributed to the stems.Short-day (SD) treatment hastened bud dormancy development followed eventually by leaf senescence. Returning the plants to LD after more than 3 months of SD-treatment did not overcome the bud dormancy regardless of whether the plants still had leaves.It is recommended that if material of Cornus alba is propagated in August, the natural photoperiod should be extended during propagation so as to improve plant growth.  相似文献   

20.
Anthropogenic ground-level ozone (O3) pollution can alter the phosphorus (P), carbon (C), and nitrogen (N) of terrestrial plants’ ecological stoichiometry, which in turn affects forest productivity, nutrient utilization, and carbon sink capacity. However, there is still quite a lot of uncertainty regarding the impact of high O3 levels on C-N-P stoichiometry in organs with a rapid turnover (i.e., fine roots and leaves) across varied functional types. This study investigated the effects of O3 on the stoichiometry of C-N-P nutrient allocation of stocks to various plant organs, with a special focus on tree species frequently employed for urban greening. The impact of O3 on C-N-P stoichiometry among different functional tree types was subsequently evaluated by reviewing the published literature. Under a pooling of all species, elevated O3 decreased and leaf C and P concentrations increased, thereby decreasing the leaf C: P ratio. Elevated O3 increased the N concentration in fine roots, thereby decreasing the C: N ratio, although no significant impact was observed in leaves. Elevated O3 significantly reduced the leaf stocks of C (CSleaf) and N (NSleaf), however, there was no observed variation in these stocks in fine roots. The content of P, C, and N in fine roots and leaves in evergreen broadleaf species exceeded those in deciduous species. Elevated O3 significantly reduced CSleaf, NSleaf, and PSleaf in deciduous broadleaf species, whereas there was a significant reduction for the same in evergreen species. The literature analysis further demonstrated a larger O3-induced increment in leaf P concentration in deciduous species as compared to evergreen species. Elevated O3 significantly increased the difference in C and N stocks between fine roots and leaves in deciduous broadleaf species, whereas this difference was observed to decrease in evergreen species. The results of this study can facilitate an improved understanding of ecological stoichiometric responses of urban greening tree species under O3 stress and the resulting nutrient use strategies.  相似文献   

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