冬枣果实发育期结果枝叶与营养枝叶矿质元素动态变化的比较

对比研究冬枣果实发育期内结果枝叶和营养枝叶片矿质元素动态变化的差异性,可为制定冬枣不同类型叶片的营养诊断标准提供理论依据。以沾化冬枣为试验材料,比较研究了沾化冬枣不同果实发育阶段（始花期、盛花期、末花期、硬核期、完熟期）结果枝叶和营养枝叶中矿质元素N、P、K、Ca、Mg、Na的含量动态变化及其差异性。结果表明,冬枣果实发育过程中,自始花期至完熟期叶片N、P含量呈下降趋势,K含量呈逐渐增高趋势,而Ca及Mg含量则呈先增高后降低的变化趋势,叶片Na含量在果实发育过程中变化较小,只有在完熟期呈现突然增高现象。在上述各生长发育阶段内,结果枝叶K含量多大于营养枝叶,而N、P、Ca、Mg、Na含量则呈相反的变化规律。方差分析表明,在盛花期至末花期内,两种类型叶片Ca、Mg含量的差异均达到显著水平（P<0.05）,N含量只有在盛花期存在显著差异,而两种类型叶片K和Na含量在各果实发育阶段内均无显著差异。叶片元素含量比值分析表明,冬枣叶片N/P在盛花期至完熟期逐渐增高,其值均大于16,可知该阶段冬枣叶片生长主要受P元素限制;K/Na、Ca/Na、Mg/Na在果实发育期内的变化规律与K、Ca、Mg元素变化规律基本类似,在完熟期这3个比值均较前期明显降低。相关分析结果表明,冬枣叶片中N/P主要由P含量决定,Ca/Na、Mg/Na分别由Ca与Na、Mg与Na共同决定,而在营养枝叶中K/Na主要由Na含量决定。综上,盛花期至末花期（6—7月）是冬枣矿质元素相对稳定时期,可作为冬枣结果枝叶和营养枝叶营养诊断的适宜时期,同时冬枣结果枝叶该时期可适当施加适量Ca、Mg肥料,从而保证冬枣的果实品质和产量。     

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。     

文心兰矿质营养特性的初步研究

为了探明文心兰的矿质营养特性,以文心兰(Oncidium Gower Ramsey‘Gold 3’)为试材,通过2009～2011年定期对各生育阶段兰株进行跟踪取样调查,初步研究了植株不同器官干物质积累及其对矿质元素吸收、分配特性。结果表明,兰株总干物质量为苗期2.42 g/株,初花期15.04 g/株,盛花期50.57 g/株,叶片所占比例最大。其中,兰株对钾的需求量较大,各时期叶片K的分配率最高,N、Ca主要分配在叶片,P、Mg和S主要分配在叶片与假鳞茎。苗期N、P、K比例为:1∶0.41∶1.57,初花期N、P、K比例为:1∶0.27∶1.45,盛花期N、P、K比例为:1∶0.31∶1.62。生产一枝花平均需要干物质4.18 g,养分N 89.76、P 10.91、K 70.44、Ca 8.33、Mg 7.43、S 7.31 mg。     

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。     

氮磷钾肥料对天鹰椒养分吸收量及干物质产量的影响

天鹰椒施用氮肥 ,增加了干物质中N ,Mg的百分含量 ,但减少了P和K的百分含量 ;施N情况下 ,N ,P ,Ca,Mg的吸收总量增加。施用磷肥 ,增加了干物质中P的百分含量 ,减少了Ca ,Mg的百分含量 ;N ,P ,K ,Ca的吸收总量增加 ,Mg的吸收总量减少。施用钾肥 ,增加了干物质中K的百分含量 ,减少了Ca ,Mg的百分含量 ,K ,P的吸收总量增加 ,N ,Ca ,Mg的吸收总量减少     

氮磷钾肥料对天鹰椒养分吸收量及干物质产量的影响

天鹰椒施用氮肥，增加了干物质中N，Mg的百分含量，但减少了P和K的百分含量；施N情况下，N，P，Ca,Mg的吸收总量增加。施用磷肥，增加了干物质中P的百分含量，减少了Ca，Mg的百分含量；N，P，K，Ca的吸收总量增加，Mg的吸收总量减少。施用钾肥，增加了干物质中K的百分含量，减少了Ca,Mg的百分含量，K，P的吸收总量增加，N，Ca,Mg的吸收总量减少。     

芋对氮磷钾吸收分配规律的研究

芋幼苗期对氮磷钾的吸收较少,发棵期和球茎膨大期吸收速率迅速增加,球茎膨大后期吸收积累速率又有所下降。总的来说,芋植株对钾的吸收最多,氮次之,磷最少,全生育期对氮磷钾的总吸收比例为1∶0.28∶1.1。幼苗期和发棵前期氮磷钾主要分布在叶片和叶柄中;其中,氮以叶片中居多,而磷和钾则以叶柄中居多。发棵后期和球茎膨大期主要分配在芋球茎中,其中氮磷的分配率为子芋大于孙芋,而钾则是孙芋中分配多于子芋。     

不同施肥方式烤烟叶片矿质元素含量变化及其与干物质积累的关系

为了研究不同施肥方式下烤烟叶片中N、P、K、Ca、Mg、B、Cu、Fe、Mn、Zn 10种矿质元素的含量变化及其与干物质积累间的相关性,于2015~2016年连续2年以南阳市烤烟品种云烟87为试材,设置3种不同的施肥方式(T1:沟灌常规施肥,T2:水肥一体化,T3:水肥一体化+黄腐酸钾)在田间进行对比试验。结果显示,烟叶中10种矿质元素含量高低表现为NCaKPMgMnFeZnBCu;水肥一体化处理矿质元素含量显著高于常规处理。不同施肥方式下叶片内矿质元素含量的变化趋势表现为N、Ca、Mn、Zn,呈先上升后下降的趋势,60~80 d达到峰值;K、Cu、Fe含量在生育期内呈逐渐下降趋势,Mg元素含量表现为先下降后上升;B、P含量在生育期内变化差异不明显;叶片内N、P、K含量之间均呈极显著正相关,表明这3种元素彼此间存在增效作用;Fe与N、Ca、Mg、Mn 4种元素含量变化呈极显著负相关,表明Fe与这4种元素间均存在拮抗作用。元素含量与干物质积累间的相关性分析表明,N、P、K在40~70 d内均与干物质积累呈显著正相关。因此与常规处理相比,水肥一体化能提高烟株对矿质元素的吸收和积累,促进后期落黄成熟,提高干物质积累量。     

肉桂人工林叶片营养元素季节累积特点及其相互关系

研究了不同林龄（3a和6a）肉桂人工林叶片5种营养元素（N，P，K，Ca和Mg）含量、季节变化动态及营养元素之间的相互作用关系。结果表明．不同林龄肉桂林叶片营养元素含量均为N〉K〉Ca〉Mg〉P，不同季节间营养元素的变异系数以Ca为最大．其次是Mg和K．然后是N，最小是P；不同林龄肉桂林叶片营养元素的季节变化规律相似，N以生长初期（3月中旬）最高，生长末期（12月中旬）最低；P和K以生长初期最低或较低．第一个生长高峰期（6月中旬）或第二个生长高峰期（9月中旬）最高或较高；Ca以第一个生长高峰期最低．生长末期最高或较高；Mg以生长初期最低．生长末期最高。肉桂植株P和K代谢之间呈正相关关系，P与Ca之间则存在显著的颉颃作用。     

荔枝叶片养分含量动态及不同比例钾、氮肥施用效应

【目的】探索荔枝叶片养分含量的周年变化规律及钾、氮肥不同施用比例对荔枝产量及其种植效益的影响,为荔枝生产中的施肥管理、营养调控与增产增效提供理论依据和实践指导。【方法】在大田栽培条件下,以1995年嫁接苗种植的国内主栽品种妃子笑为试材,设置钾、氮肥不同施用比例（K2O/N分别为0.6、0.8、1.0、1.2和1.4）5个处理,随机区组排列,于2009~2012年3个生长季在广东省惠州市荔枝主产区进行试验。在荔枝不同生育期定期采集荔枝叶片测定矿质元素含量,荔枝成熟时于田间按小区实收称重测产。【结果】荔枝叶片不同生育期的养分含量存在明显差异;在整个生育期,叶片养分含量的大小均表现为N﹥K﹥Ca﹥Mg﹥P﹥S﹥B﹥Zn﹥Mo;叶片K与Ca、Mg含量有极显著的负相关关系,K与Zn含量呈显著负相关,而Ca、Mg、Zn含量两两间呈显著正相关;叶片N与S、B含量呈显著负相关,而S与B呈极显著正相关;叶片P与Ca、Si含量呈显著负相关,而Ca与Si呈显著正相关。等氮基础上随着K2O/N比的提高,荔枝产量和种植效益均出现先升高后降低的规律;以K2O/N比例为1.0~1.2时荔枝产量最高、效益最好。【结论】在我国荔枝主产区以保持钾、氮肥养分施用比例（K2O∶N）为1.0~1.2为宜。     

施用氮、磷、钾对密植梨枣生长与叶片养分季节动态的影响

以山地梨枣(Zizyphus jujuba Mill. cv. Lizao)为试验材料,采用野外试验与室内分析,研究了黄土丘陵区山地滴灌下施用氮磷钾对矮化密植梨枣叶片8种营养元素（N、P、K、Ca、Mg、Fe、Mn、Zn）季节动态变化规律以及施肥对梨枣生长,产量及品质的影响。结果表明:不同生育期梨枣叶片养分含量变化具有一定的规律性。开花坐果期（5月上旬至7月上旬）,叶片N、P、K含量处较高水平,Mg、Fe、Mn、Zn含量处于较低水平。果实膨大期（7月中下旬到8月下旬）,叶片N、P有一个相对稳定的含量,K快速下降,而Fe、Mn、Zn含量上升。果实成熟期（9月初到10月初）,叶片N、P、K含量下降,Mg、Fe、Mn、Zn则是缓慢上升并趋于稳定。叶片N、P、K、Mn含量之间呈正相关,Ca、Mg、Fe、Zn含量之间也呈正相关关系,叶片N、P、K之间达极显著正相关关系,而N、P、K与Ca、Mg、Fe、Zn含量之间呈负相关关系。施氮肥可促进前期枣树新枝生长和枣果膨大;施磷肥可提高产量,达到33210 kg/hm2;施钾肥可明显提高枣果品质。     

Effect of magnesium on early taro growth

Abstract

Little research has been conducted on magnesium (Mg) nutrition of taro [Colocasia esculenta (L.) Schott cv. ‘Bun Long']. In this study, we evaluated the effects of varying levels of Mg (0.0, 0.05, 0.1, 0.2, 0.4, and 0.8 mM) on taro plants grown hydroponically for 33 days. Magnesium treatment effects were evaluated for dry matter biomass, leaf area, and N, P, K, Ca, Mg, Na, Mn, Fe, Cu, Zn, and B concentrations of old and young leaves. Dry matter of leaves (young, old, and total), roots, corms, petioles, and total biomass were significantly higher in all plus‐Mg treatments than in the zero‐Mg treatment. These same biomass parameters were not different among treatments with Mg (0.05 to 0.8 mM). Leaf area (young, old, and total) did not differ significantly with varying levels of Mg. A quadratic model described the relationship between Mg levels in leaves and solution Mg (r² = 0.99). Young and old leaf Mg concentrations did not differ. Total leaf Mg concentration ranged from 0.07% to 0.42% for the lowest and highest Mg levels in solution, respectively. Leaf Mg effects on total leaf DM was best fit using segmented regression (r² = 0.95), with a corresponding critical leaf Mg concentration (95% of maximum predicted leaf DM) of 0.14%. No significant interactions were observed between Mg and other mineral nutrients. Critical leaf Mg concentration is based on the vegetative growth stage of taro and could be a key index for taro producers who emphasize vegetable leaf, rather than corm production.     

Growth,yield and nutrient uptake of taro grown under upland conditions

There is a scarcity of basic information on dry matter accumulation by various plant organs, nutrient uptake, and yield of taro [Colocasia esculenta (L.) Schott] grown under upland conditions. These data are essential for the development of technological packages, growth simulation models, and decision support systems designed to promote agrotechnology transfer of the crop in the tropics. Two taro cultivars were planted and harvested for biomass about every six weeks during the growing season. At each harvest, plants were separated into various plant parts and their dry matter and nutrient content were determined. There were no significant differences (P<0.05) in total and edible dry matter content between cultivars. However, cultivar ‘Lila’ absorbed significantly smaller amounts of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and zinc (Zn) than cultivar ‘Blanca’, suggesting that it had a higher nutrient‐use efficiency. Fresh corm yields were not significantly different and averaged 20,221 kg/ha for both cultivars.     

Patterns of mineral nutrient fluctuations in soybean leaves in relation to their position

Dry weight accumulation in blades for the trifoliolate leaf as well as the concentration per gram of dry weight and accumulation of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) were determined during the vegetative and reproductive phases at different leaf positions of soybean [Glycine max (L) Merrill, var. Halle] grown in the field without fertilization. The leaf blades at each position were sampled three times at seven day intervals. Mature (middle) leaves showed a higher rate of dry weight accumulation particularly during the vegetative stage in comparison to the older (lower) and younger (upper) leaves. These differences increased with the progress of plant growth. The minimization to zero of the rate of dry weight accumulation in blades after the development of pods is differentiated in leaves of different age. The N, P, and K concentration in leaf blades increase and those of Ca and Mg decrease from older (lower) to mature (middle) and younger (upper) leaves. Rates of N and P accumulation at the vegetative stage are greater than the rate of dry weight accumulation. During the reproductive stage, P mobilization and transport to reproductive sinks was observed. Older and mature leaves sustain significant levels of N and P up to the end of the plant life cycle. In the upper leaves, the decline of N and P concentration during the same period is ascribed to dilution and change of the carbon/nitrogen (C/N) ratio due to the late increase of dry weight. Potassium in blades of mature and upper leaves seems to be mobilized to reproductive sinks. This did not seem likely for the lower leaves. High Ca concentration in the blades was attributed to the high level of available Ca in the soil, combined with the prevalence of dry growth conditions during the summer. The rate of Ca accumulation is smaller than the rate of dry weight accumulation during the vegetative stage and greater during the reproductive one. The Mg fluctuations indicate a small influence of reproductive sinks on Mg concentration in the blades. The older leaves have the greatest Ca and Mg concentrations compared to the mature and upper leaves. In lower leaves, indications of faster Mg redistribution are found. Iron, Cu, and Zn concentrations in the blades are higher before flowering, then afterwards in a contrary manner than that for Mn. A decline of Fe, Cu, Zn, and Mn concentration in blades from the lower to the mature and upper leaves was determined. Iron shows the greatest change with the highest concentration being during the early vegetative stage and a rapid decline shortly afterwards. Older leaves were found to be significant Fe reserves during the vegetative stage, while after pod development, they present an impressive accumulation of Zn and Mn.     

Effect of salt stress on Growth and Ion accumulation of alfalfa (Medicago sativa L.) cultivars

Alfalfa (Medicago sativa L.) yield and nutrient contents may be affected under salinity condition. Thus, this experiment was conducted to determine the effect of three salinity levels (60, 120, and 180 mM NaCl) on shoot and root dry weights, and mineral contents of three alfalfa cultivars. With the increasing salinity levels sodium (Na) and magnesium (Mg) contents increased; but potassium (K), nitrogen (N), phosphorous (P), calcium (Ca), zinc (Zn), and copper (Cu) contents and root and leaf weights decreased; however, changes in these traits depended on cultivar and salinity level. However, Rehnani, a tolerant cultivar, had the lowest Na and Mg contents and the highest K, N, P, Ca, Zn, and Cu contents and dry weights under all of the salinity levels. Moreover, leaf dry weight and leaf P content had the highest correlation with salt tolerance suggesting that these traits may be used as a marker for selecting salts that are tolerant among genotypes in alfalfa.     

不同氮钾施用水平对番茄营养吸收和土壤养分变化的影响

以“辽园多丽”番茄为试材,在日光温室内桶栽条件下,研究不同氮钾水平对番茄养分吸收和土壤养分变化的影响。结果表明:在一定范围内,随着土壤中施氮量和施钾量的增多,番茄叶片和果实中含氮量、含钾量越高。说明氮、钾两种元素可互相促进彼此的吸收,但是,超过一定范围,会降低果实中氮素和钾素的比例。不同氮钾处理对植株磷素的吸收影响不大。土壤中增施钾肥在一定程度上抑制了番茄植株对钙素和镁素的吸收,土壤中氮素含量的高低对叶片中钙的吸收影响不大,土壤中适当氮水平可促进番茄叶片和果实中镁素的吸收和积累,施氮量过高则降低了果实中钙素、镁素的积累。随着土壤中氮肥和钾肥施入量的增多,土壤中碱解氮和速效钾的含量呈升高趋势,不同施钾水平条件下,中等钾素处理土壤中碱解氮含量较高。     

Seasonal dynamics of mineral nutrients by walnut tree reproductive organs

The dry weight accumulation per male and female flower as well as the concentration per gram of dry weight and the accumulation of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) were determined in walnut tree (Juglans regia L.) catkins and female flowers at the stage of flower bud and during the flower development. Catkin emergence was accompanied by a very fast hydration of the tissues. After the catkin matured, the fresh and dry weights were reduced. The female flower development period was accompanied by the dry and fresh weight increase. Total N, P, K, Fe, Mn, Cu and Zn concentrations in catkin buds were detected at lower levels, Mg in equal levels, and Ca at higher levels as compared to the nutrient concentrations in young growing leaves. The estimated values of the ratio NCmfb/NCygl were: total N = 0.54, P = 0.83, K = 0.56, Ca = 1.5, Mg = 1.0, Fe = 0.46, Mn = 0.71, Cu = 0.85, and Zn = 0.60. Nutrient concentration in female flower buds was detected in almost equal levels with the exception of total N and Fe. The estimated values of the ratio: NCffb/NCygl were: total N = 0.57, P = 1.1, K = 1.17, Ca = 1.06, Mg = 0.9, Fe = 0.47, Mn = 1.0, Cu = 0.92, and Zn = 0.85. Total N, P, Mn, Cu, and Zn accumulations in the catkin were increased during the fast growing phase and decreased after catkin maturing. Potassium, Mg, and Fe accumulation continued to increase in the mature catkin. Calcium accumulation decreased at a very late mature catkin phase. Total N, P, and K accumulation rates during the catkin fast growing phase were higher than the dry weight accumulation rate. Calcium, Mg, Fe, Mn, Cu, and Zn accumulation rates at the same period were lower or equal to dry weight accumulation rates. In mature catkins, the total N, P, Mn, Cu, and Zn depletion rates were higher than the dry weight depletion rate. The continual increase of K, Ca, Mg, and Fe accumulation in mature catkin resulted in the increase of nutrients concentration also. Total N and P showed the highest remobilization values from mature catkin of 51.4% and 45%, respectively. Calcium, K, Mg, Cu, Mn, and Zn remobilization values estimated to be 22.1%, 7.5%, 3.2%, 45.3%, 33.4%, and 31.8%, respectively. Iron showed no remobilization at all. Nutrients remobilization from catkins as compared to the leaves had almost similar values for total N, Zn, and Cu, higher for P, Ca, and Mn, and lower for Mg, Fe, and K. Accumulation of all nutrients in female flowers increased after fertilization. The dry weight accumulation rate was higher than the nutrient accumulation rates.     

Seasonality of nutrients vis-à-vis fruit quality of pomegranate cv. Bhagwa on vertisol

The temporal changes of nutrient concentration in leaves and their accumulation in fruit are good indicators of plant nutrient demand for each developmental stage. Seasonality of nutrients in leaves and fruits of pomegranate and their relation with fruit quality was evaluated in commercial orchards using cv. “Bhagwa.” The concentration of nitrogen (N), phosphorus (P), potassium (K), sulfur (S), iron (Fe), zinc (Zn) and boron (B) in leaves decreased while calcium (Ca), magnesium (Mg), manganese (Mn) and copper (Cu) concentration increased during fruit growth and development. Total nutrient accumulation increased gradually in fruit and translated into growth of arils, and increase in juice content and total soluble solids, however as the biomass accumulation in fruit was much faster than nutrient accumulation, concentration of majority nutrients except Mg decreased rapidly, followed by slow and continuous decrease till maturity. During fruit enlargement, demand for N, P, K, Fe, Cu and Zn was high while requirement for Ca, Mg and S was high during fruit development.