板栗叶片及土壤养分含量对产量影响

为了解迁西板栗“燕山早丰”叶片及土壤养分含量对产量的影响,通过路径分析和相关性分析对迁西县17个代表性“燕山早丰”板栗园土壤和叶片养分状况与产量进行分析,得出叶片不同养分元素以及土壤养分含量对板栗产量影响的直接作用和间接作用。结果显示,路径分析中残差值均小于0.4,即板栗叶片或土壤的养分元素含量对产量的影响权重均超过60%;高产果园中,提高板栗叶片N、P、Ca、Mn、Fe、Mg含量,提高土壤N、Fe、Mn含量均有利于提高板栗产量;低产果园中,提高板栗叶片N、Ca、Mg含量,提高土壤N含量均有利于提高板栗产量。因此,在高产果园中,向土壤中增施N、P、Fe、Mn等肥料,向叶面喷施Ca、Mg等叶面肥料均有利于提高板栗产量;低产果园中,向土壤中增施N肥和向叶面喷施Ca、Mg、Fe、Cu等元素叶面肥料是提高产量的有效措施。     

不同早实核桃品种叶片矿质元素含量变化及其与产量的关系

试验于2010~2011年连续2年以济源市4个早实核桃品种香玲、鲁光、中林1号、薄丰为试材进行了对比试验,研究了不同采样时期叶片中N、 P、 K、 Ca、 Mg、 Fe、 Cu、 Mn、 Zn 9种矿质营养元素的含量变化及其与产量的关系。结果表明,早实核桃叶片中9种元素的含量在年周期内呈规律性变化,含量高低依次为 Ca＞N＞Mg＞P＞K,Fe＞Mn＞Zn＞Cu。不同品种各元素的含量变幅最大为127.69~169.53 mg/kg（Mn）,最小为2.1~92.26 g/kg（K）。不同早实核桃品种叶片内矿质元素含量的年变化趋势表现为N、 P、 K总体上呈下降趋势,最高含量为展叶期（4月20日）分别为36.79、 5.54、 2.93 g/kg,最低在落叶前期（9月28日）,分别为17.45、 2.66、 1.86 g/kg;Ca、 Mg、 Fe、 Mn 4元素含量的变化总体上表现为前期低后期高;Cu、Zn含量的变化有差异但差异不明显。总的来看, 5~7月份,即新梢速长期（5月20日）至硬核期（7月20日）是核桃树养分稳定的时期, 叶片中N、 P、 K含量之间呈极显著的正相关, N、 P与Ca、 Mg、 Mn、 Cu间呈极显著的负相关,可以认为N、 P、 K之间存在增效作用,Ca、 Mg、 Mn、 Cu 对N、 P 和 K 均存在一定的拮抗作用。元素含量与产量的相关分析表明,N、 P、 K在新梢速长期均与产量达（极）显著正相关,相关系数分别为0.819、 0.843和0.895。因此, 利用叶片进行营养诊断最佳,采样时间以新梢速长期（5月20日前后）为宜。     

豫西地区红富士苹果叶片营养诊断

通过22个有代表性果园苹果叶片矿质营养分析,采用诊断施肥综合法（DRIS）对豫西红富士苹果进行了叶片营养诊断。结果表明,豫西红富士苹果叶片N、P、K、Fe、Mn、Cu、Zn的适宜含量分别为:22.54±3.00 g/kg、2.42±0.28 g/kg、9.31±1.40 g/kg、104.47±15.03 mg/kg、33.89±5.77 mg/kg、3.38±0.39 mg/kg、29.71±4.91 mg/kg,N:P:K的适宜比例为1:0.08～0.14:0.31～0.55。DRIS诊断参数确定为N/P、K/N、K/P、Cu/N、P/Mn、Cu/P、P/Zn、K/Fe、K/Cu、Zn/N和K/Zn,这11种比例关系的变异程度均表现出低产园（变异系数范围为20.44％～40.82％）明显高于高产园（变异系数范围为8.69％～23.95％）;高产园和低产园的营养不平衡指数（NII）分别为39和88。对Fe、Mn和Zn元素需求强度较大的果园分别占供试果园的86％、82％和50％。相对于高产园,低产园元素间关系较不平衡;总体而言,豫西红富士苹果园需求强度较大的元素是Fe、Mn或Zn,其次是N或P。     

粉蕉矿质元素吸收积累与分配特征

为探明粉蕉矿质营养元素的累积分配特征,以主栽品种广粉1号为试材,采用彻底刨根、分解取样的方法,研究了干物质的构成特点、各器官矿质元素含量和累积分配特性。结果表明:粉蕉植株总干质量为17.6 kg/plant,其中叶片占16.4%,假茎占32.8%,球茎占9.6%,果实占37.3%,果轴占1.1%,根占2.8%。平均每株累积吸收N 167.0g、P 19.3g、K 521.7g、Ca 118.3g、Mg 54.7g、S 16.6g、Fe 6650.5mg、Mn 16142.9mg、Cu 152.3mg、Zn 607.7mg、B 212.2mg、Mo 4.2mg,养分比例N:P:K:Ca:Mg:S为1:0.12:3.12:0.71:0.33:0.10。其中N、P、Ca和S主要向叶片、假茎和果实分配,K和Mg主要向假茎分配,Fe主要向叶片、根和球茎分配,Cu主要向假茎和果实分配,Zn和Mo主要向叶片、假茎和球茎分配,B和Mn主要向假茎和叶片分配。为获得60t/hm2的高产,粉蕉需要吸收N 385.6kg、P 44.6kg、K 1205.1kg、Ca 273.3kg、Mg 126.6kg、S 38.3kg、Fe 15.4kg、Mn 37.3kg、Cu 352.0g、Zn 1403.8g、B 490.1g、Mo 9.6g。     

香蕉营养诊断的DRIS标准的初步研究

运用诊断与推荐综合系统(DRIS)标准建立的常规方法,通过比较香蕉低产组和高产组叶片N、P、K、Ca、Mg和S养分含量以及两元素间的养分比和养分积,初步筛选出P/N、N.K、N.Ca、N/Mg、N/S、P.K、P/Ca、P/Mg、P.S、Ca/K、K/Mg、K.S、Ca/Mg、Ca/S和S/Mg作为DRIS参项,并初步提出香蕉DRIS诊断标准。     

渭北旱塬红富士苹果不同时期叶片营养诊断

为推动渭北旱塬苹果合理施肥,通过测定红富士苹果不同时期叶片养分含量,并运用Beaufils、Jones和Elwali&Gascho提出的3种DRIS指数计算法对红富士苹果营养状况进行诊断。结果表明,从6月到8月红富士苹果叶片各养分元素含量变化存在差异,高产果树(单株产量>25 kg)叶片N含量呈先降低后升高趋势,P含量逐渐降低;低产果树(单株产量≤25 kg)叶片N含量一直降低,P含量变化则与高产叶片N相同。其他元素在两种果树中的变化趋势一致,K和Zn含量降低,Ca和Mg含量升高,Cu、Fe和Mn呈先升高后降低趋势。不同时期根据DRIS标准程序确定的重要诊断参数不同;与Elwali&Gascho提出的DRIS诊断指数计算法相比,采用Beaufils和Jones的方法得出的各元素诊断指数不但与其含量相关性高,且需肥顺序差异不大,Beau-fils方法得出高产果树6月到8月最缺乏的元素为K、Fe、Ca+Mg,Jones方法为K、Ca、Ca+Mg,低产果树均为K、Fe、N。综上,本研究建议针对不同时期进行红富士苹果叶片营养状况评价。     

象山“红美人”柑橘营养诊断研究

通过对 “红美人”优势产区浙江象山柑橘园进行土壤和叶片矿质元素含量的测定及营养状况诊断,为“红美人”柑橘高产优质施肥提供科学依据。以“红美人”优势产区31个代表性柑橘园为研究对象,根据土壤有效养分分级标准及叶片诊断综合施肥法(DRIS)、修正诊断综合施肥法(M-DRIS)和标准适宜含量偏差百分数法(DOP),对柑橘园土壤和叶片营养状况进行诊断。结果表明:(1)研究的31个果园中90.30%的柑橘园土壤pH处于适宜水平,土壤碱解N、有效B处于缺乏和低量水平的柑橘园分别占35.70%、32.26%,其它指标处于适宜兼丰富水平;(2)除土壤交换性Ca外,高产园和低产园养分指标差异不显著,而且土壤单一养分指标与产量基本无相关性;(3)土壤交换性Ca、交换性Mg、有效Mn和有效B的含量与叶片中相应元素存在显著或极显著正相关;(4)高产园和低产园除叶片Mn元素外,其它矿质养分含量差异不显著,叶片单一矿质养分与产量基本无相关性;(5)根据DRIS、M-DRIS和DOP法对31个“红美人”柑橘园进行叶片营养诊断。DRIS、M-DRIS和DOP的平均营养不平衡指数值与产量呈显著负相关。不同方法诊断的产量限制元素排序基本一致,DRIS和M-DRIS法建立的排序均为:Mn>K>Fe;DOP法建立的排序为:Mn>Zn>Fe。常年大量施肥导致土壤养分累积,土壤养分已经不是产量限制因素。而树体内各矿质养分间的比例平衡关系对产量影响更为显著,应采用叶片营养平衡诊断为主、土壤营养诊断为辅的诊断方法,从而制定更准确的施肥方案。     

鹰嘴蜜桃养分累积分布特性与流胶病的关系

在广东省鹰嘴蜜桃产区挖取成熟期中高产鹰嘴桃3株,研究鹰嘴蜜桃的养分累积及分布特性与流胶病发生的关系,并开展鹰嘴蜜桃平衡施肥示范。结果表明,在鹰嘴蜜桃各器官中营养元素含量 N、 Ca、 Mg、 S、 Mn、 Cu、 Zn、 B,以叶片含量最高;Fe、 Mo、 Si含量以根最高;K含量以果肉最高;P含量在叶片、 根和果肉中相差不大。每生产50 kg果实,鹰嘴蜜桃树体（除根系外）需要累积N 2.137 kg、 P 0.184 kg、 K 1.261 kg、 Ca 2.119 kg、 Mg 0.205 kg、 S 0.094 kg、 Si 0.053 kg、 Cu 582 mg、 Zn 10912 mg、 Fe 17847 mg、 Mn 8689 mg、 B 2152 mg、 Mo 20.9 mg。每收获50 kg果实,其带走的养分量为N 0.620 kg、 P 0.077 kg、 K 0.678 kg、 Ca 0.263 kg、 Mg 0.035 kg、 S 0.021 kg、 Si 0.003 kg、 Cu 226 mg、 Zn 1651 mg、 Fe 3601 mg、 Mn 436 mg、 B 958 mg、 Mo 8.8 mg。初步推断出鹰嘴蜜桃流胶病的发生是与其树体K/N低和N/B高有关。通过平衡施肥示范可有效减轻流胶病的发生,明显提高鹰嘴蜜桃果实品质和风味。     

配方施肥对设施‘87-1’葡萄植株矿质元素含量及果实品质的影响

为制定基于品质指数的最佳理论施肥方案及营养诊断标准,研究了不同施肥配比和植株矿质元素变化动态与品质形成的关系。以设施‘87-1’葡萄为试材,连续多年进行5416配方施肥试验,测定植株矿质元素含量及果实品质,并对其进行Topsis综合评价,计算品质指数。研究矿质元素含量与品质指数的相关性,确定营养诊断因子。应用非完全正交方差分析法和组分营养诊断法分别制定最佳综合品质的施肥方案及营养诊断标准。研究结果表明,单粒重在各处理条件下的分布范围是4.3～5.0 g。T10处理的可溶性固形物含量最高,为18.5%。T3处理的果实硬度最高,为471.9 g。T3处理的品质指数最高,为0.6071;除T6、T8、T14、T16处理外,其他处理品质指数均高于T1处理,增幅为1.8%～33.4%。成熟期果实N、成熟期叶柄P、成熟期叶柄K、成熟期叶片Ca、转色期叶柄Mg被选作为营养诊断因子。高优园矿质元素含量适宜范围为N 1.0～2.4 mg/g、P 1.0～3.0 mg/g、K 4.0～10.4 mg/g、Ca 2.9~9.6 mg/g、Mg 0.6～9.7 mg/g,低优园的需肥顺序为K>Ca>N>Mg>P,其中K和Ca元素含量表现偏低,其他元素含量充足。当单粒重、可溶性固形物、硬度和品质指数达到最佳时,每公顷的建议施肥总量分别为736.5、1332.0、788.3和1430.3 kg。在本试验条件下,品质指数达到最佳时的元素N∶P∶K∶Ca∶Mg理论配比为3∶3∶4∶3∶2,其N、P2O5、K2O、CaO、MgO施肥量分别为375.0、141.0、506.3、337.5、70.5 kg/hm²。     

新疆南部石榴矿质营养DRIS诊断初步研究

采用大田调查、田间定位试验与室内化学分析相结合的方法,运用诊断与推荐施肥综合系统(DRIS),对高、低产组石榴叶片N、P、K、Ca养分分析数据进行不同表示式计算,初步筛选出N/P、N/K、N.Ca、K/P、Ca/P和Ca/K为DRIS诊断参数,并初步提出石榴DRIS诊断标准。通过对田间定位试验结果的营养诊断表明,DRIS适合新疆南部石榴的施肥诊断。     

施肥深度和用量对华南果园土壤氮磷流失的影响

Fertilizers are heavily applied in orchards of the hilly and mountainous topography of South China and may increase nutrient loadings to receiving waters. A simple runoff collecting system was used to measure the effects of different fertilization treatments on total N and P concentrations of surface runoff in a Chinese chestnut （Castanea mollissima Blume） orchard in Dongyuan County, Guangdong Province, China. In such orchards, fertilizer was typically applied in two short furrows or pits on either side of each tree. Treatments included three application depths （surface, 10 cm and 20 cm）, and three application rates （low, median and high）. Results showed that 90.5% of the runoff water samples had a total N concentration higher than 0.35 mg·L^-1 and 54.2% had a total P concentration higher than 0.1 mg·L^-1. Fertilizer application at all depths and at all but the lowest rate significantly increased total N and P concentrations in runoff water. Fertilization with chemical compound fertilizer at a soil depth of 20 cm produced significantly lower （P 〈 0.05） total N concentration in runoff than both surface and 10-cm depth fertilization, and significantly lower （P 〈 0.05） total P concentration in runoff than surface fertilization. Total N and P concentrations in runoff significantly increased with the application rate of organic fertilizers. With the exception of total P concentrations, which were not significantly different between the control and fertilization at a rate of 119 kg P ha-1 in organic form, all the other fertilization treatments produced significantly higher total N and total P concentrations in runoff than the control. A fertilization depth ≥ 20 cm and an application rate ≤ 72 kg N ha-1 or 119 kg P ha^-1 for compound organic fertilizer was suggested to substantially reduce N and P runoff losses from hillslope orchards and to protect receiving waters in South China.     

Diagnosis and Recommendation Integrated System Norms,Sufficiency Range,and Nutritional Evaluation of Arabian Coffee in Two Sampling Periods

ABSTRACT

The objective of this work was to establish and compare Diagnosis and Recommendation Integrated System (DRIS) norms with the sufficiency range approach, and apply these methods on nutritional diagnosis of Arabian coffee, in field samples collected in summer and winter in Southern Brazil. DRIS norms and sufficiency range were established in groves with average biennial yield equal or above 3000 kg ha^{? 1}. The “t” test was used to verify the differences between the sufficiency range and the DRIS norms. The foliar concentrations of nitrogen (N), phosphorus (P), and sulfur (S) were higher in summer, and iron (Fe), and manganese (Mn) in winter. The reference values should be specific for the period of the year. There were differences in the foliar nutritional diagnosis, between the DRIS method and the sufficiency range approach. In samples during the summer analyzed with DRIS, copper (Cu), S, potassium (K), and zinc (Zn) were considered more limited nutrients and Mn, S, K, and calcium (Ca) when the sufficiency range was used.     

广西柑橘叶片微量营养元素含量状况研究

【目的】研究广西柑橘主产区树体微量营养元素含量状况,为柑橘平衡施肥提供依据。【方法】2017年在广西壮族自治区15个柑橘主产县 (区) 选择207个代表性果园采集叶片样品,对5种必需微量营养元素进行定量分析。【结果】柑橘叶片的Fe、Mn、Zn、Cu和B含量分别为37.9～278.5 mg/kg (均值99.6 mg/kg)、13.5～588.6 mg/kg (均值79.4 mg/kg)、5.4～68.2 mg/kg (均值20.1 mg/kg)、1.2～196.1 mg/kg (均值18.8 mg/kg) 和32.9～281.1 mg/kg (均值111.3 mg/kg)。叶片 Fe、Mn、Zn、Cu和B不足 (缺乏或低量) 的比例分别占11.6%、5.3%、84.1%、33.3%和0.5%,处于适量水平的比例分别占67.6%、72.5%、15.9%、34.8%和41.5%,处于超标 (高量或过量) 水平的比例分别占20.8%、22.2%、0.0%、31.9%和58.0%。叶片Fe含量大部分果园处于适量水平,全州县、德保县、阳朔县和兴安县Fe含量不足的程度较严重,而永福县、来宾市、西乡塘区、隆安县、马山县Fe含量超标的比例较高。叶片Mn含量大部分果园为适量水平,仅荔浦县、灵川县、德保县、隆安县和马山县存在Mn含量不足的果园;除兴安县和上林县外,其他县 (区) 都存在Mn含量超标的果园,其中永福县、阳朔县、富川县、钟山县、灵川县、来宾市、隆安县和马山县Mn超标程度较为严重,均超过25%。Zn不足的果园多且普遍,每个采样县 (区) 的柑橘叶片Zn含量不足的比例均很高,全州县、富川县、兴安县、灵川县、德保县、隆安县、马山县和上林县的叶片Zn含量处于不足的比例均达到100%。叶片Cu含量波动大,不足、适量、超标的样本数约各占1/3,全州县、荔浦县、灵川县和德保县叶片Cu含量主要处于不足水平;永福县、阳朔县、兴安县、钟山县和马山县叶片Cu含量主要处于适量水平;富川县、武鸣县、来宾市、西乡塘区、隆安县和上林县叶片Cu含量主要处于超标水平,超标果园种植的主要是溃疡病敏感品种,与长期使用含铜杀菌剂有关。叶片B含量超标的果园比例最大,达到58.0%;全州县、阳朔县、钟山县、德保县和上林县果园叶片B含量主要处于适量水平,永福县、荔浦县、兴安县、武鸣县、来宾市、西乡塘区、隆安县和马山县果园叶片B含量主要处于超标水平。【结论】广西柑橘主产区大部分柑橘园存在一种或多种微量元素不足或过量的问题。总体上Fe、Mn、Cu养分状况良好,但同时存在不足和超标问题;Zn不足问题突出,B超标比例较高。生产上特别需要重视补充Zn肥,控制B肥施用。     

BORON APPLICATION ON A CHESTNUT ORCHARD: EFFECT ON YIELD AND QUALITY OF NUTS

Although boron (B) deficiency in chestnuts (Castanea sativa Mill.) has been identified in Portugal and B fertilization was carried out in some orchards, the post-treatment evaluations have not been made to date. So the objective of this trial was to confirm the B deficiency and to quantify the effect of B applications to the soil on nut yield and quality. In October 2006, a fertilizer trial was established in a 15 year-old orchard in a very acid soil derived from siliceous schists. Soil liming and a basal fertilization were carried out in 16 trees and two levels of sodium tetraborate (Granubor, 14.6% B) were applied to eight trees: control (B0) and 100 g of Granubor per tree (B1). In the beginning of September chestnut leaves were collected from five trees and analyzed for macro- and micronutrients. Nut productivity was measured per tree and some nut quality parameters were evaluated, including the chemical composition of the kernel (soluble sugars, starch, total fiber, crude protein, and crude fat) in 2007, and dry matter, nut caliber, and fruit damage in 2007 and 2008. Boron fertilization of chestnuts significantly increased nut production: 75% in the first year (8 kg and 14 kg per tree, respectively, in the B0 and B1) and, in the second year, was over four times higher (4 kg and 17 kg per tree, respectively, in the B0 and B1). No significant differences were found in dry matter, nut caliber, nut damage and chemical composition of the kernel in the first year, but in the second year lower fruit damage by chestnut tortrix (P<0.0089) was observed. Foliar analyses exhibit relatively low B concentrations in the control trees (average value of 8 mg kg^?1) in both years, while in the fertilized trees the foliar B concentration were in average 61 mg kg^?1 in the first year, and 34 mg kg^?1 in the second year. The large drop in the foliar B concentration in the second year suggests the need to monitoring the nutrient status of chestnut orchards or more frequent of B application than usual practice.     

Observations on Manganese Deficiency and Toxicity in Some Australian Native Plants

Analysis and research on the nutrition of some Australian native plants as well as diagnostic analysis of failed native plant gardens reinforces the view that manganese (Mn) availability is a major factor in the edaphology and cultivation of Australian native species. Yellow Kandosol soils on sandstone show a unique endemic floral assemblage. These soils show low total soil Mn levels of only 20–30 mg/kg. Despite this, endemic species such as Eucalyptus haemastoma and Acacia suaveolens show greater foliar Mn levels (around 291 and 389 mg/kg, respectively) than iron (Fe) levels, with Fe/Mn ratios as low as 0.14 and 0.27. During pot trial work on artificial soils created from crushed sandstone and green waste compost that were designed to research phosphorus (P) and calcium (Ca) nutrition, some interesting data on Mn uptake were collected. Levels of foliar Mn as high as 1250 and 389 mg/kg, respectively, accumulated in E. haemastoma and A. suaveolens when soils were artificially acidified to pH 4.7 (CaCl₂) using ferrous sulfate. These Mn levels were associated with visible toxicity symptoms in foliage of E. haemastoma but not in A. suaveolens. Foliar Mn in both species showed a strong inverse correlation (R² > 0.93) with soil pH. Previous research has shown that eucalypts from this floral assemblage are prone to Mn toxicity when grown in conditions of high soil Mn availability. Diagnostic analysis of soils and foliage for a client with horticultural problems in a native plant landscape showed severe chlorosis in a wide range of native species due to Mn deficiency induced by neutral soil pH (around 7.0 in CaCl₂). Such soil pHs are considerably greater than those of the plant’s natural distribution. Despite apparently elevated soil P and the appearance of what looked like P toxicity, foliar P levels were not sufficiently elevated to conclude acute P toxicity but rather simple and severe Mn deficiency. The work suggests that induced Mn deficiency and toxicity may be underdiagnosed problems in the cultivation of many Australian native plants.     

Monitoring Nutrient Status of Ber (Zizyphus mauritiana) Fruit Trees in Semi-arid and Arid Regions of Northwest India through Diagnostic Recommendation and Integrated System Approach

The Diagnostic Recommendation and Integrated System (DRIS) was employed to interpret nutrient analyses of leaf tissues from ber fruit tree orchards grown in semi-arid and arid areas of Punjab in northwest India. The DRIS norms were established for various nutrient ratios obtained from the high-yield population and were used to compute DRIS indices, which assessed nutrient balance and their orders of limitation to yield. Nutrient sufficiency ranges derived from DRIS norms were 0.688–1.648%, 0.184–0.339%, 1.178–1.855%, 1.064–1.768%, 0.234–0.391%, and 0.124–0.180% for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S) and were 55–205, 26–80, 17–33, and 5–11 mg kg^?1 for iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu), respectively. According to these DRIS-derived sufficiency ranges, 79%, 76%, 76%, 75%, 84%, and 72% of samples were sufficient, whereas 13%, 15%, 21%, 14%, 7%, and 18% of total samples were low in N, P, K, Ca, Mg, and S, respectively. For micronutrients, 84%, 85%, 77%, and 86% of samples were sufficient, whereas 6%, 3%, 8%, and 2% of samples were low in Fe, Mn, Zn, and Cu, respectively.     

Identifying nutrient imbalances in pomegranate (Cv. Bhagwa) at different phonological stages by the diagnosis and recommendation integrated system

The diagnosis and recommendation integrated system (DRIS) approach was used to interpret nutrient analyses of leaf tissues from pomegranate cv. Bhagwa orchards grown in southwestern Maharashtra, India. The DRIS norms were established for three growth stages,viz. 50% flowering, fruit development and first harvesting of pomegranate. Various nutrient ratios were obtained from high-yielding population and were used to compute DRIS indices for diagnosing nutrient imbalances and their order of limitation to yield. Nutrient sufficiency ranges at 50% flowering derived from DRIS norms were 1.32–2.15% nitrogen (N), 0.18–0.24% phosphorus (P), 1.29–1.99% potassium (K), 0.64–1.20% calcium (Ca), 0.23–0.45% magnesium (Mg), 0.16–0.26% sulfur (S), 103.04–149.12 mg kg^?1 iron (Fe), 39.60–72.85 mg kg^?1 manganese (Mn), 15.99–26.10 mg kg^?1 zinc (Zn), 6.16–9.32 mg kg^?1 copper (Cu), 23.38–39.88 mg kg^?1 boron (B) and 0.29–0.47 mg kg^?1 molybdenum (Mo). Similarly, the sufficiency range at fruit development and first harvesting was developed for computing DRIS indices. The requirement of Fe, Mg, S, Zn and N by the pomegranate plant was higher at 50% flowering and fruit development stages. According to these DRIS-derived indices, 87.85, 73.83, 70.09, 69.16 and 65.42% orchards were deficient in Fe, S, Mg, Zn, and N, respectively, at 50% flowering, while 70.03, 66.36, 63.55, 61.68, and 68.22% orchards were found to be deficient in respective nutrients during the fruit development stage.     

DRIS and Sufficient Range Approaches in Nutritional Diagnosis of “Valencia” Sweet Orange on Three Rootstocks

Abstract

Among several methods of diagnosis for nutritional status, two are more important: the Sufficiency range approach (SRA) and the diagnosis and recommendation integrated system (DRIS). This research compared DRIS with SRA, the diagnostic method currently used by the citrus industry in São Paulo State, Brazil. The study was conducted in irrigated, commercial groves of “Valencia” sweet orange more than six years old and with yield above 40 t ha^{? 1} in Mogi Guaçú, São Paulo State. Data pertaining to yield, tree spacing, rootstock, and foliar concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), and boron (B) in non-fruiting terminals for each plot were processed for the years 1994 through 1998. DRIS indices were calculated by the Jones method of the intermediate functions. Index of nutritional balance (INB) was calculated by the average of the sum (disregarding the sign) of all nutritional index values and the dry matter index. Results indicated that, for the conditions of this experiment: (1) DRIS, when compared with the SRA, complements nutritional diagnosis because it establishes an order of deficiency or excess for each nutrient and detects deficiencies or excesses not considered by SRA; (2) There was agreement between the two methods for nutritional diagnosis of K; (3) Cu, Mn, and Fe concentrations were determined as deficient by DRIS, but were classified as adequate or excessive by SRA.     

板栗细根碳、氮、磷化学计量时间变异特征

【目的】 探讨生长季内板栗 (Castanea mollissima) 细根碳 (C)、氮 (N)、磷 (P) 化学计量特征,为有针对性地培育板栗,提高有效经济产量提供理论依据。 【方法】 以河北省迁西县北京林业大学经济林 (板栗) 育种与栽培实践基地6年生板栗树为研究对象,在生长季内 (4—10月份) 采用连续根钻法 (内径为8 cm),分别在距树干50 cm和100 cm的不同土层 (0—20 cm、20—40 cm和40—60 cm) 处取样,分析计算了不同空间分布上板栗细根C、N、P的化学计量特征。 【结果】 板栗细根C、N、P含量的均值分别为382.01 g/kg、7.99 g/kg和1.06 g/kg,C/N、C/P和N/P均值分别为50.48、377.35和7.62。在生长季中,板栗细根C、C/N、C/P在6—9月份基本维持在较高水平且6月份最大,而N和P在6月份含量相对较少,在4月份达到最大值,N/P则在生长季末达到最大值。板栗细根C、N、P含量在空间上也表现出差异。C含量在20—40 cm最多。这一土层中,距树干50 cm和100 cm处,C含量的最大值分别出现在7月份和6月份,生长季C含量分别增加了26.82 g/kg和11.84 g/kg。N和P含量在0—20 cm最多。这一土层中,距树干50 cm处,N含量在4月份最高,P含量7月份最高,生长季N含量和P含量分别减少了1.39 g/kg和0.60 g/kg。距树干100 cm处,N含量在4月份最高,P含量8月份最高,生长季N含量和P含量分别减少了2.91 g/kg和0.56 g/kg。整体变异分析表明,板栗细根N、C/N、C/P、N/P受不同月份的影响最大,C、P受不同土层深度的影响最大,距树干距离因素的影响是最小的。通过对N、P含量和N/P比值的分析可知,该地区板栗生长受到N、P共同限制,且更易受到N限制。 【结论】 板栗细根C、N、P及其化学计量比在时间和空间上差异显著,其受到的影响因素不同。在进行水肥管理时,应根据不同时间和空间上板栗细根的特征进行合理的管理,并充分考虑N、P含量尤其是N含量的限制。