氮磷钾氯平衡施肥对菜心产量及品质的影响

在大棚无土栽培条件下,采用"416-B"最优混合设计研究N、P2O5、K2O、Cl配比对菜心产量和硝酸盐积累的效应及其最佳配比进行研究.结果表明:N、P2O5、K2O、Cl合理配施能提高菜心产量,降低菜心硝酸盐含量.其中N、P2O5、K2O与产量呈正效应,Cl与产量呈负效应,N与菜心硝酸盐含量呈正效应,P2O5、K2O、Cl与菜心硝酸盐含量呈负效应.综合考虑,确定高产优质菜心的最佳营养配方:N、P2O5、K2O、Cl的编码值(真实值,g/0.9 m2)分别为0.49(18.58),1.49(8.95),1.16(22.11),0.23(33.31),对应的产量707.12 g/0.9 m2,硝酸盐含量612.01 mg/kg,Vc含量170.42 mg/kg.     

荔枝年生长周期内N、P、K营养动态规律与施肥管理体系

通过3年大田试验探索荔枝年生长周期内N、P、K营养规律,验证由高氮、高磷钾、高钾复合肥组成的荔枝平衡施肥管理措施的适用性。结果表明,荔枝年生长周期内,收获期N、P、K营养水平降至最低,随后因施肥而迅速恢复,在秋梢老熟到花芽分化期达年周期内最大值,此后随着开花结果N、P、K营养水平逐渐下降,至新的收获期又降至最低水平。秋梢和果枝的N、P、K水平因生长期的不同而明显变化,然而肥料用量(3～5kg/树)和N∶P∶K比例对树体N、P、K水平的影响较小。每个生育期结果母枝的N、P、K含量依次为N>K>P。收获期到开花前是树体营养恢复阶段,开花到果实生长发育期是消耗体内贮藏态N、P、K的过程。在荔枝年生长周期内,分别在收获期、秋梢老熟期和坐果期施用高氮复合肥、高磷钾复合肥和高钾复合肥能保障年周期内荔枝树体N、P、K营养水平处于最佳状态。     

施肥水平对生姜光合特性及NPK吸收的影响

研究了Ｎ、Ｐ、Ｋ施用水平对生姜光合特性和ＮＰＫ吸收的影响。结果表明：中水平处理（每６６７ｍ２施Ｎ４０ｋｇ、Ｐ２Ｏ５７．５ｋｇ，Ｋ２Ｏ４０ｋｇ）叶片叶绿素含量高，光合和蒸腾强，对ＮＰＫ吸收多；低水平（Ｎ３Ｐ７．５Ｋ４０，Ｎ４０Ｐ０Ｋ４０，Ｎ４０Ｐ７．５Ｋ０）和高水平（Ｎ８０Ｐ７．５Ｋ４０，Ｎ４０Ｐ１５Ｋ４０，Ｎ４０Ｐ７．５Ｋ８０）施肥处理，上述指标均有不同程度的降低。     

Some responses of cucumber,grown in beds of peat,to N,K and Mg

Two levels of N and four levels of K, applied to beds of sphagnum peat before planting (Experiment A), were tested in factorial combination with three concentrations of N (50, 175 and 300 mg 1^-1) and two of K (50 and 250 mg T1) in the liquid feed. In three cucumber crops grown, Mg was supplied or omitted before planting as a split plot factor (96 subplots). In two further crops (Experiment B), grown in fresh peat, six concentrations of N (20-320 mg 1^-1) were tested in the liquid feed, all other nutrient levels being constant. In Experiment A, the early yield was reduced by low and high levels of N. The main effect of N on the final yield was not significant, but maximum yield was achieved with 175-300 mg 1^-1 N in the liquid feed where the peat received a small amount of ureaformaldehyde (15 g m“2) and Mg fertilizer. The N x Mg interaction became increasingly marked with successive crops; the loss in yield due to Mg deficiency (<31%) increased with the amount of N applied. K deficiency reduced the yield by up to 66%, and very high levels of K also tended to decrease the yield. The K x Mg interaction became more marked with time and the loss in yield due to Mg deficiency (<23%) increased with the amount of K applied. Leaves from N, K and Mg deficient plants contained <2.5% N, <1.0% K and <0.28% Mg respectively. In Experiment B, where N was supplied only in the liquid feed, the highest yield was obtained at 220 mg 1^-1. The relation between yield and the total amount of N supplied in the feed was defined by a quadratic regression.     

Effects of N–P–K deficiency and temperature regime on the growth and development of Lilium longiflorum ‘Nellie White’ during bulb production under phytotron conditions

One-year-old scale bulblets of Lilium longiflorum Thunb. ‘Nellie White’ (Easter lily) were grown under a combination of six constant day/night temperature regimes and five N–P–K nutrient treatments under short days for 107 d (growing period 1 or GP-1) to compare the effects on growth and development and bulb production. Results during GP-1 were as follows: failure of bulblets to produce a shoot (“no-shows”) was found at high temperatures (30/26 and 26/22 °C) and not influenced by the nutrient treatments. Flower bud abortion was observed in the minus-N, minus-P, and minus-N–P–K treatments at high temperatures (30/26 or 26/22 °C), but not observed at any temperatures in the complete and minus-K treatments. The loss of bulb fresh weight in minus-N treated bulblets was less than in the other treatments resulting in less root and shoot growth in the minus-N treatment. At the intermediate temperatures where growth was highest, omission of N, P, K, or all three resulted in losses in stem bulb fresh weight, stem plus leaf fresh weight, number of flowers, and stem root fresh weight. Omission of N, P, or all three nutrients resulted in lowest basal root fresh weight. Bulb N and K concentrations were lowest in plants grown with complete nutrient solution at the two coldest temperature regimes (14/10 and 10/6 °C). Bulb P concentration was lowest at the three coldest (18/14, 14/10 and 10/6 °C) and the warmest (30/26 °C) temperature regimes. Stem length was shorter when P was omitted. Omission of any of the three nutrients resulted in lower concentrations of the other nutrients. The one exception was where low K did not affect N concentration. In the second phase of the experiment, plants grown at 18/14 °C and irrigated with the complete nutrient solution for 107 d (GP-1) were continued at this day/night temperature regime and five N–P–K nutrient treatments for another 89 d under long days (growing period 2 or GP-2). Results during GP-2 were as follows. Basal bulb yield was not impacted by omission of N, P, or K, or all three. Of all growth measurements, only stem plus leaf fresh weight was lower and only when all three nutrients (minus-N–P–K) were omitted. At the end of GP-2, basal bulb concentrations of N and P did not differ from the concentrations in bulbs at the beginning of GP-1; however, K concentration was lower at the end of GP-2. Omission of N or P further resulted in lower bulb K concentration, suggesting that a moderate supply of N, P, and K be applied during GP-2 since an additional year of bulb production is needed to produce forcing-sized bulbs.     

Interaction of short day and timing of nitrogen fertilization on growth and flowering of ‘Korona’ strawberry (Fragaria × ananassa Duch.)

The effects of timing of nitrogen (N) fertilization relative to the beginning of a 4-week floral-inducing short-day (SD) period have been studied in ‘Korona’ strawberry plants under controlled environment conditions. Groups of low fertility plants were fertilized with 100 ml of calcium nitrate solution for 3 days a week for a period of 3 weeks starting at various times before and at the beginning of the SD period, as well as at different times during the SD period. All plants, including SD and long day (LD) control plants, received a weekly fertilization with a low concentration complete fertilizer solution throughout the experiment. Leaf area, fresh and dry matter increments of leaves, crowns and roots, as well as leaf chlorophyll concentration (SPAD values) were monitored during the experimental period. A general enhancement of growth took place at all times of N fertilization. This was paralleled by an increase in leaf chlorophyll concentration, indicating that the control plants were in a mild state of N deficiency. When N fertilization was started 2 weeks before beginning of the SD period, flowering was delayed by 7 days, and this was gradually changed to an advancement of 8 days when the same treatment was started 3 weeks after the first SD. The amount of flowering was generally increased by N fertilization although the effect varied greatly with the time of N application. The greatest flowering enhancement occurred when N fertilization started 1 week after the first SD when the number of flowering crowns and the number of inflorescences per plant were more than doubled compared with the SD control, while fertilization 2 weeks before SD had no significant effect on these parameters. Importantly, the total number of crowns per plant was not affected by N fertilization at any time, indicating that enhancement of flowering was not due to an increase in potential inflorescence sites. No flowering took place in the control plants in LD. Possible physiological mechanisms involved and practical applications of the findings are discussed.     

Vegetative growth, flowering and leaf nutrient concentration of boronia as affected by nitrogen level and form

Boronia (Boronia megastigma Nees, family Rutaceae) is an Australian woody shrub, producing strongly scented flowers at nodes. Increasing N levels from 0 to 25 mM in the nutrient solution increased the production of nodes, lateral shoots from these nodes and further nodes on these lateral shoots. With the same level of N, the order of number of node and lateral shoot production by N form was: combined NH₄⁺plus NO₃⁻ > NH₄⁺alone > NO₃⁻ alone. This increase in the number of nodes subsequently translated into increased number of axils initiating flower buds and then into fully developed flowers. However, increasing N levels decreased the percentage of flower buds developing to anthesis and individual flower weight. These decreases were attributed to continued vegetative growth during flower development. Increasing N levels increased the leaf N concentration with the concentration in the order NH₄⁺ + NO₃⁻ > NH₄⁺ > NO₃⁻. Nitrogen form did not affect the leaf tissue concentration of P, K⁺, Ca²⁺ and Mg²⁺. At lower N levels, the concentrations of these nutrients in the leaf tissue were higher and may have reached toxic levels, causing toxicity symptoms on leaves. At higher N levels, the concentrations of these nutrients were diluted due to increased growth and no toxicity symptoms were produced.     

长期施用氮磷钾肥对黄土高原地区苹果产量及土壤养分累积与分布的影响

对连续8 a施用氮磷钾肥的黄土高原地区‘红富士’苹果园的产量及土壤养分变化进行了研究,以探明长期施用氮磷钾化肥对苹果产量与土壤养分累积与分布的影响。结果表明,施用氮磷钾化肥(NPK处理)显著增加了苹果产量,增产率为12.8%～128.3%,增产率随施肥年限增加有增加趋势。NPK处理增加了果园土壤的有效氮、磷、钾含量,其累积量在不同土层中的分布差异较大。与对照(CK)相比较,NPK处理使0～20 cm、20～40 cm和40～60 cm土层中的速效氮含量平均分别增加了24.9 mg·L-1、36.9 mg·L-1和49.7 mg·L-1,速效磷增加了20.1 mg·L-1,12.6 mg·L-1和4.3 mg·L-1,速效钾增加了50.9 mg·L-1、61.8 mg·L-1和31.2 mg·L-1。这表明长期施肥下,果园土壤中速效氮的累积量随着土层深度增加,速效磷的累积量随土层深度减少,速效钾累积主要分布在0～40 cm土层。相关性分析表明,20～40cm土层的速效氮和速效磷含量与当年的苹果产量呈显著正相关关系,土壤速效养分含量与上一年度苹果产量的相关性较差。     

Putting back what we take out,but how much?: Phosphorus and nitrogen additions to farmed Leucadendron ‘Safari Sunset’ and Leucospermum ‘Succession’ (Proteaceae)

Proteaceae are adapted to low-nutrient soils in the various regions where they occur. However, harvesting of flowering stems for the cut-flower industry must eventually cause soil nutrient depletion sufficient to reduce yields. Different N forms, and N and P concentrations were supplied to two Proteaceae cultivars (Leucadendron ‘Safari Sunset’ and Leucospermum ‘Succession’) in a controlled fertigation experiment, and appropriate concentrations for maximum growth with minimum nutrient accumulation or loss were determined. Small additions of N (0.025–0.1 mM) significantly improved growth of both cultivars growing on Strandveld sandy soil. Larger additions of N (up to 2 mM N) resulted in poor growth (both cultivars) and N accumulation in the soil (Safari Sunset). Small additions of P (<10 μM) significantly improved growth of both cultivars and resulted in no accumulation or loss of P in the soil. Larger additions of P (up to 500 μM) resulted in poor growth, P toxicity symptoms and P leaching from the upper soil layers. Best N forms in descending order of both plant visual appearance and vegetative yield were: urea ≥ ammonium nitrate > ammonium sulphate > calcium nitrate. Phosphorus toxicity symptoms were associated with increased concentrations of leaf P, Ca and Fe. Under conditions of maximum growth (10 μM P and 0.1 mM N) Safari Sunset removed 18 ± 0.6 g N, 1.5 ± 0.1 g P, 5.3 ± 0.6 g K and Succession removed 5.5 ± 0.2 g N, 0.3 ± 0.02 g P, 3.1 ± 0.5 g K over 6 months. At maximum growth, plants acquired more N and P amounts than were supplied, but supplying higher N and P concentrations adversely affected growth. Thus, a more complex or slow-release form of N and P than urea and soluble phosphate, respectively, may provide enough N and P to replace losses from the farm soil at the low concentrations required for proteas.     

不同氮处理下增施CO2对番茄叶片养分含量的影响

为探究不同氮处理对番茄植株叶片养分的影响及增施CO2的效果。以番茄"鸿途"为试验材料,在2个自然光照人工气候室内,采用苗钵基质栽培,设置5个氮素处理的营养液(50、150、250、350、450 mg·L^-1,分别设为N1~N5)、2个CO2浓度(300、600μL·L^-1,分别设为C1、C2),分别测定植株开花期、坐果期、果实膨大期生物量及叶片硝态氮和矿质元素含量。结果表明:中氮处理(N 250~350 mg·L^-1)下,植株干质量、叶片硝态氮含量以及矿质元素N、P、K、Ca、Mg含量均较高。增施CO2处理后,番茄植株干质量较C1处理增加了10.2%,叶片N、K、Mg含量都增加了20%左右,P含量没有变化,Ca含量降低了25.67%;低氮处理(N 50 mg·L^-1)下,番茄植株干质量、叶片硝态氮含量以及矿质元素N、P、K、Mg、Ca含量均较对照N3处理低。增施CO2处理后,植株的总干质量没有显著增加,其叶片硝态氮含量以及N、P、K含量也没有显著变化,而Ca含量在开花期和坐果期较C1处理分别增加了37.72%、15.45%,Mg含量在开花期较C1处理增加了43.86%;高氮处理(N 450 mg·L^-1)下,植株干质量较N3处理降低了18.03%,叶片硝态氮含量较N3处理增加了111.44%,叶片N、Ca、Mg含量与N3处理接近均较高,P、K含量较N3处理均降低了10%。增施CO2处理后,植株干质量较C1处理增加了35.92%,叶片硝态氮含量增加不显著,叶片N、K、Mg含量较C1处理分别增加了19.06%、27.82%、24.87%,而叶片P含量变化不显著,叶片钙含量在番茄开花期、坐果期和果实膨大期都较低,较C1处理分别降低了21.37%、17.16%、7.75%。综合番茄生长各项指标及经济效益,在营养液N浓度为250~350 mg·L^-1时,增施CO2浓度到600μL·L^-1(C2)最能促进开花期番茄植株叶片养分含量的增加。     

The effect of fruiting status on nutrient composition of litchi (Litchi chinensis Sonn.) during the flowering and fruiting season

Summary

The pattern of leaf composition was investigated in three litchi orchards (cvs Bengal and Tai So) in subtropical Australia (Lat 27°S). Leaves were sampled from fruiting and non-fruiting branches from flowering to fruit harvest. The response to fruiting varied with the nutrient and the orchard. The major effect of fruiting was to reduce leaf K in two of the orchards. Leaf N, P, Zn and Na were lower in fruiting branches in a third of the orchards, while leaf Ca, Mg, Mn and B levels were higher. The levels of these nutrients in the other two orchards, and those of Cu and Fe, were not significantly affected by fruiting status. Strong seasonal effects from flowering to harvest on the leaf contents of most nutrients followed the typical pattern as leaves aged. Most nutrients were more stable during flowering to just after fruit set. The levels of most nutrients were similar in both leaf and fruit. The major exceptions were K which was about twice as high in the fruit and B which was five times higher in the leaves. The uptake of all nutrients continued throughout fruit growth in proportion to the accumulation of fruit dry weight and reached a maximum rate during the final period of aril (flesh) development. The relative order for final content in the fruit was: K>N>P>Mg>Ca>Na>Fe>Zn>Cu>Mn>B. The choice of branch type and time of sampling would influence the diagnosis for N, K, Ca, Mg and Fe at these sites. It is recommended that leaves for diagnostic purposes in litchi be collected from fruiting branches two to six weeks after fruit set.     

生长调节剂对麻疯树成花及营养物质的影响

运用正交实验设计,用不同水平的6-苄氨基嘌呤（6-BA）+赤霉素（GA₃）+肥种处理麻疯树茎尖,研究外源物质对麻疯树花芽分化及树体内营养物质的影响。结果表明:各处理对麻疯树成花数量有显著影响,6-BA（2 mg/L）+GA₃（50 mg/L）+肥种（氮）为最优促花组合,正交实验设计中以6-BA（0.5 mg/L）+GA₃（50 mg/L）+肥种（氮）的促花效果较好;GA₃是影响麻疯树成花的主要因子。处理促进营养生长和生殖生长,二者交错进行。处理株叶片内氮、可溶性糖、淀粉、C/N比、钾的含量和变化趋势均呈增加-降低-再增加的S型模式。磷的含量在早期达到最大,之后便持续下降。叶片内钾在最高含量是最低含量的4.8倍,变幅最大,磷和钾呈极显著正相关。枝条生长与叶片内可溶性糖含量显著负相关。     

干旱胁迫对砂糖橘树体营养的影响及其与成花的关系

 为了探讨干旱胁迫对砂糖橘（Citrus reticulata‘Shatangju’）树体营养的影响及营养与成花的关系,设置了不同干旱胁迫时间（0、2、4、6、8周）和不同氮素水平（每次每盆单独施N︰P₂O₅︰K₂O为15︰15︰15的复合肥5 g和另外加尿素6 g两水平）两因素进行盆栽试验研究。结果表明,干旱胁迫4周后树体氮素和钾素增加,而非结构性碳水化合物糖和淀粉呈下降趋势,磷素无明显变化,树体中C/N,P/N与对照相比降低。各养分含量及相互比率在干旱胁迫4周左右存在一个明显拐点,且与砂糖橘的成花时间表现高度一致。每枝成花数量和氮素及钾素有显著正相关关系,和C/N呈负相关关系,而和树体磷含量无显著相关关系。在正常供水情况下不同营养状况砂糖橘均未成花,但在干旱胁迫情况下氮素、钾素以及C/N和成花特性间有很好的相关关系。     

Effects of nitrogen and phosphorus on root and shoot growth of Cotoneaster divaricata Rehd. & Wils.

Root and shoot growth rates of Cotoneaster divaricata were determined using a growing system of polyvinyl chloride pipe cylinders in which longitudinal sections could be removed for periodic root observations. Plants were fertilized with nitrogen (N), phosphorus (P), and potassium (K). N, as NH₄NO₃, was applied weekly at levels of 0, 250 or 500 mg/l and P, as H₃PO₄, was incorporated in the medium at levels of 0, 5 or 50 mg/l. K, as KCl, was maintained in the medium at a 150 mg/l level by soil tests conducted weekly. Shoot growth was increased after N application. However, no difference was observed between N levels. P increased shoot growth only at the highest N level applied. Although root growth was not increased by either N or P, high N levels inhibited root growth, whereas P stimulated root growth. No correlation (r = 0.19) was observed between shoot and root growth.     

Hormone effects on in vitro proliferation and rooting of Grevillea explants

Explants of Grevillea rosmarinifolia A. Cunn. and Grevillea×semperflorens F.E. Brigs ex Mullig., obtained from vegetative stem segments, were grown on a modified MS medium, which was supplemented with different contents of cytokinins (BA or K) to evaluate optimal conditions for bud proliferation. Auxins (NAA or IBA) were tested to evaluate rooting.

The multiplication rate was often higher in G. rosmarinifolia than in G.×semperflorens. Explant activity varied significantly depending on the cytokinin type and its concentration. The addition of cytokinins to the culture medium often promoted an increase in the number of shoots produced by each propagule, but at the highest BA concentration, shoot differentiation was inhibited in Grevillea×semperflorens. Only the higher concentrations studied (5–10 mg/l) produced better results with K, whereas BA was more effective at 1–2 mg/l. Rooting efficiency of the young shoots was lower in G. rosmarinifolia than in G.×semperflorens. IBA promoted root development in both species and was more effective at the highest concentration (1 mg/l). NAA gave better results at low concentrations (0.2 mg/l) in G. rosmarinifolia, while it had slight or negative effect on rooting of G.×semperflorens.     

不同铵硝配比对辣椒产量、养分积累和氮肥利用率的影响

通过设施大棚辣椒盆栽试验,设置不施氮肥(CK)、铵态氮与硝态氮的氮质量比分别为0:100(A0N100)、25:75(A25N75)、50:50(A50N50)、100:0(A100N0)5个处理,研究不同铵硝态氮配比对辣椒产量、养分积累和氮肥利用率的影响.结果表明,与CK相比,不同铵硝配比处理增加了辣椒的果实数、鲜果...     

套袋、喷钙对酥梨果实矿质营养和品质的影响

酥梨果实套袋后,对叶鲜、干重,叶绿素和N、P、K含量,未发现有明显不良影响。而成熟果实中K、Ca、Mg含量值则分别下降10.6%、58%、9.3%,总糖下降0.9%,维生素C下降7.4mg/100g。平均单果变小,减产约13.4%。若采取喷钙后套袋,同单纯套袋相比,上述各项指标含量,均有明显提高,甚至接近或略超过CK处理的含量。对不套袋的梨果喷施(3种)钙肥,与CK相比,上述各项指标含量均有明显提高,增产2.9%～7.4%。3种钙肥喷施的综合效果,腐殖酸钙和高能钙稍好于补钙王。     

Nutrition of five species of container-grown acacia,boronia, choisya and eucalyptus

Plants were grown in peat/perlite (1:1, vv) in factorial experiments designed to compare various levels of Osmocote (26% N), superphosphate and sulphate of potash.Foliage growth of acacia and boronia was strongly promoted by high N fertilisation, with boronia being less tolerant of low levels. Compared with low additions, high % added P depressed growth, particularly when coupled with high N, and more than doubled foliar P levels in both plants similar to the excessive luxury consumption in P-intolerant Proteaceae. Choisya and 2 eucalypt species responded strongly to added N and foliage growth was poor at very low levels. Choisya was not damaged by very high P additions and there were no indications of luxury uptake. Foliage growth of the 2 eucalypts was not promoted by high added P, but foliar P was strongly increased.     

福建柑桔园营养施肥状况及其施肥改进建议

以福建省永春等10县（市）70片（≥3．5hm2）柑桔示范园为代表,通过土壤、叶片分析及施肥状况的综合诊断得出的结果表明：84％的示范园土壤显著酸化（pH＜5．5）,主要是施用N、P、K化肥造成的;营养失调也普遍存在于示范围中,其中主要元素缺Ca、P吸收障碍及微量元素B、Cu的过量尤为普遍;施肥中有机肥不足,P、N肥滥用,Ca、Mg、K肥欠缺;叶片K、Mg并不简单受其土壤有效成分的影响,叶片K与土壤"全N／有效K"、"水解N／有效K",叶片Mg与土壤"代换Mg／代换Ca"呈极显著相关（P＜0．01,r=-0．36、-0．39、0．49）。据此,对以红壤为主要土壤类型的福建柑桔产区的施肥提出了改进建议。     

Relationship between light,fruit and leaf mineral content with albinism incidence in strawberry (Fragaria x ananassa Duch.)

A study was conducted in strawberry to establish a relationship between shading, mineral nutrient of leaves and fruits with albinism incidence. Plants grown under shade produced albino fruits in higher proportion than those grown in open fields. Similarly, plants under shade produced smaller sized fruits and have lower fruit yield. Among cultivars, Etna had highest incidence of albinism (49.6%) and Sweet Charlie the lowest (14.4%). Dry matter content (%), concentration of five major nutrients, viz. N, P, K, Ca, Mg, S and N:Ca and K:Ca nutrient ratios did not differ significantly in the leaves of plants producing normal or albino fruits. However, in contrast, the concentration of K was notably higher (1.97 mg g⁻¹ fresh tissue weight) and that of Ca was lower (0.098 mg g⁻¹ fresh tissue weight) in albino fruits than normal ones. Consequently, the ratios of N:Ca (11.34) and K:Ca (20.08) were higher in albino fruits than normal ones. Cultivars also differed widely in respect to dry matter (%), mineral content and nutrient ratios. Thus, it appears that lower light intensity favours the development of albinism in strawberry, and it seems that calcium is not the basic cause of albinism, but increased vigour associated with overuse of N and K might be positively associated with it.