Nutrition of fig (Ficus carica L.) under hydroponics and greenhouse conditions

In this investigation the extraction curve of macronutrients (N, P, K, Ca, Mg) and micronutrients (Fe, Cu, Zn and Mn) were determined in the cultivation of fig. A system of intensive production of fig in greenhouse and hydroponics was established with 1.25 plants m^?2. The determination of the nitrogen content was done by the micro-Kjeldahl method. The P was by the yellow molybdovanadate method throughon a spectrophotometer. The K was determined by flamometry and the Ca, Mg, Fe, Cu, Zn and Mn were determined by atomic absorption spectrophotometry. Of the organs analyzed, the stem was the that accumulated more dry matter, then, the leaves and finally the fruits. The nutrient extraction dynamics presented similar upward behavior in all nutrients. The demand for macronutrients in decreasing order was N?>?K?>?P?>?Ca?>?Mg and for the micronutrients Cu?>?Fe?>?Mn?>?Zn.     

Rootstock Effect on Nutrient Concentration of Sweet Cherry Leaves

The present investigation aimed to study the leaf mineral composition of sweet cherry trees on different rootstocks, since the literature data on uptake efficiency of different rootstocks is inconsistent. Results confirmed the different uptake efficiency of rootstocks. The efficiency of ‘GiSelA 6’ root is emphasized in uptake and supply of leaves with nitrogen (N), phosphorus (P), potassium (K), zinc (Zn), boron (B), and manganese (Mn), but trees on this rootstock tend to develop calcium (Ca), magnesium (Mg), and copper (Cu) deficiencies. The Prunus mahaleb rootstocks on calcareous sandy soil are efficient supplier of N, P, K, Ca, Mg, Fe, and Cu, but this root tends to develop Zn, B, and Mn deficiencies. Prunus avium seedling as rootstock proved to be less efficient in supply of leaves by N, P, K, Ca, and Cu. Prunus fruticosa ‘Prob’ root showed tendency in developing several leaf nutrient deficiencies. The applied fertilizer program led to low nutrient levels or even deficiency symptoms in leaves.     

Critical nutrient concentrations and antagonistic and synergistic relationships among the nutrients of NFT‐grown young tomato plants

Critical concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), and manganese (Mn) with respect to dry matter yield end antagonistic and synergistic relationships among these nutrients were studied in which tomato (Lycopersicon esculentum L.) was grown in recirculating nutrient solution (NFT). Increments of nutrient elements in the nutrient solution increased the proportional rate of the corresponding nutrient elements. Increasing levels of N negatively correlated with plant P and positively correlated with Ca, Fe, and Zn. Iron and Mn contents of the plants were increased and N, K, Ca, and Mg were decreased as a function of P applied. Increases in K in the nutrient solution caused increases in the concentrations of K, N, P, and Zn, and decreases in the concentration of Ca and Fe. Applied Ca increased the concentrations of Ca and N, and decreased the concentrations of P, Mg, Fe, Zn, and Mn. Potassium, Ca, and Fe contents of the plants were decreased and Zn increased, while N, P, and Mn were not affected by the increasing levels of external Mg. Iron suppressed the plant Mg, Zn, and Mn contents. Synergism between Zn and Fe was seen, while P, K, Ca, Mg, and Mn contents were not affected by Zn levels. Potassium, Ca, Mg, and Fe were not responsive to applied Mn, however, N and P contents of the plants were decreased at the highest levels of Mn.     

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.     

李营养累积、分布及叶片养分动态研究

基于保障生态和果品安全以及合理实施果园养分管理的前提,对大石早生李树体各部位营养元素积累、分布以及各营养元素的周年变化规律进行了分析.结果表明:①营养元素在各个器官的相对含量,除K、Zn在果实中含量最高外,N、P、Ca、Mg均以叶片中含量为最高,以叶片做营养诊断是适宜的.②大石早生李树体营养元素N、P、K、Ca、Mg、Fe、Zn的元素比值为10.00:1.26:6.42:12.57:2.46:1.87:0.14.⑧100 kg鲜果的养分吸收量分别为:N 772.47g,P74.25 g,K 730.33g,Ca874.16 g,Mg 169.82 g,Fe 66.05 g,Zn 7.53 g,N:P:K的比例为1.00:0.10:0.95.④N、P、K、Ca、Mg、Fe、Zn、Mn、Cu的含量随物侯期呈规律性变化.生长季初期,N、P、K、Zn、Cu的含量迅速下降,Fe、Mn、Ca、Mg呈逐渐上升的趋势;中期这9种元素总体变化幅度较小;后期Fe,Cu.N、P、K的含量呈下降趋势,Mn、Zn、Ca,Mg依然上升.本结果既丰富了国内李营养理论,同时又为制定合理的施肥措施及建立绿色优质果品科技示范基地提供了理论依据.     

Aerial accumulation and partitioning of nutrients by hard red spring wheat

Abstract

Periods of maximum hard red spring (HRS) wheat (Jriticum aestivum L.) nutrient demand need to be determined in order to develop best nutrient management practices, and to provide data for nutrient uptake modeling. Aerial (aboveground biomass) whole plant samples of irrigated HRS wheat were collected from the field at 16 growth stages and separated into leaves, stems, heads, and grain for dry matter determinations and analyzed for N, P, K, Ca, Mg, S, Cl, Zn, Mn, Fe, and Cu concentrations. Accumulation curves were computed for each plant part for the growing season from compound cubic polynomial models based on accumulated growing degree units (GDUs). Total aerial accumulations of dry matter, N, P, K, Ca, Mg, S, Cl, Zn, Mn, Fe, and Cu were 14400, 116, 30.8, 103, 9.2, 9.3, 15.2, 32.3, 0.18, 0.58, 2.05, and 0.045 kg/ha, respectively. Grain at maturity accumulated greater than 78% of the total aerial N, P, and Zn, while it contained less than 20% of the aerial accumulated K, Ca, Cl, and Fe. Nitrogen and Fe were rapidly accumulated near 200 GDU, while P, K, Ca, Mg, S, Cl, Zn, Mn, and Cu were most rapidly accumulated near 600 GDU. Accumulation rates were 183, 2.9, 0.90, 0.72, 0.008, 1.41, 0.29, and 0.12 kg/ha/d for dry matter, N, P, K, Ca, Mg, S, and Cl, respectively, and 136, 1.7, 0.48, 0.13, 0.004, 0.78, 0.20, and 0.02 g/ha/d, respectively, during grainfill. This plant information suggests the timing of in‐season nutrient applications, and when integrated with other agronomic practices could improve overall nutrient management for HRS wheat in the northern Great Plains.     

Inoculation of ‘Golden Delicious’ Apple Trees on M9 Rootstock with Azotobacter Improves Nutrient Uptake and Growth Indices

ABSTRACT

Roots of young ‘Golden Delicious’ apple on M9 rootstock were inoculated with four strains of Azotobacter chroococcum, which were isolated from various soils. Effects of these strains in combination with different levels of nitrogen (N) fertilizer and compost on plant growth and nutrient uptake were studied over two seasons. Therefore, a factorial arrangement included four strains of A. chroococcum, two levels of N-fertilizer (0 and 35 mg N kg^?1soil of ammonium nitrate) and two levels of compost (0 and 12 g kg^?1 soil of air-dried vermicompost). Among the four strains, AFA₁₄₆ was the most beneficial strain, as it increased leaf area, leaf potassium (K), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and boron (B) uptake and root N, phosphorus (P), potassium (K), Mn, and Zn. The combination of AFA₁₄₆ strain, compost and N fertilizer increased leaf uptake of Ca, Mg, Fe, Mn, Zn, and B, and root uptake of P, K, Ca, Mg, Mn, and copper (Cu), and root dry weight.     

Seasonal dynamics of mineral nutrients and carbohydrates by walnut tree leaves

The dry weight accumulation per leaf 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 leaves (Juglans regia L.) during a complete life cycle. Additionally, the dynamics of plant nutrient concentration in leaf petiole sap and carbohydrate accumulation in leaves were studied in relation to the main life cycle events of the walnut tree. Total N, P, K, Cu, and Zn concentrations decreased, whereas that of Ca, Mg, and Mn increased during the season. Iron concentration fluctuated around a mean value. Total N, P, K, Mg, and Cu concentrations detected in younger mature leaves were at the sufficient level, whereas Ca, Fe, Mn, and Zn concentrations were at higher levels as compared to those previously reported. All the detected nutrient accumulations increased abruptly during leaf ontogeny and leaf maturation until a maximum level was attained in the younger mature leaves. Similarly, sucrose, glucose, and fructose accumulation were observed at the same period. The rates of total N, P, Cu, and Zn accumulation were lower than the rates of the observed dry matter accumulation and nutrient concentration dilution. Potassium and Mn accumulation rates were almost equal, whereas those for Ca and Mg were higher as compared to the dry matter accumulation rate. The fast embryo growing phase resulted in a considerable decrease in dry weight, total N, P, K, Cu, Zn, and carbohydrate accumulation, and to a lesser degree in Ca, Mg, and Mn accumulation. Nutrient accumulation reduction in leaves by the influence of the growing fruits were estimated to be: total N 52%, K 48%, P 29.5%, Mg 16.3%, Ca 15%, Fe 51.2%, Cu 55.2%, Zn 37.3%, and Mn 5.4% of the maximum nutrient value of the younger mature leaves. Old leaves preserved nutrients before leaf fall as follows: total N 25.4%, P 45%, K 31%, Ca 74.8%, Mg 76.5%, Mn 89.2%, Fe and Zn 50%, and Cu 37%. Nutrient remobilization from the senescing old leaves before leaf fall were: total N 22.6%, P 25.5%, K 21%, Ca 10.2%, Mg 7%, Fe 3.2%, Mn 5.4%, Cu 8%, and Zn 13.3% of the maximum value in the younger mature leaves. In early spring, the absorption rates of N, P, and Ca were low while those of Mg, Fe, Mn, Cu, and Zn were high. During the fast growing pollen phase, the N, P, Fe, Mn, Cu, and Zn concentrations were reduced. Calcium concentration is supposed to be more affected by the rate of transpiration rather than during the growing of embryo. Calcium and Mg concentrations in the sap were negatively correlated. The detected K concentration level in the sap was as high as 33 to 50 times that of soluble N, 12 to 21 times to that of P, 5 times to that of Ca, and 10 to 20 times to that of Mg. The first maximum of starch accumulation in mature leaves was observed during the slow growing embryo phase and a second one after fruit ripening. Old senescing leaves showed an extensive carbohydrate depletion before leaf fall.     

脐橙幼苗新老叶片养分含量对大、中量元素短期缺乏的差异性响应

  【目的】  对比大、中量养分短期缺乏下脐橙新、老叶片中11种必需元素含量及变化,并分析缺素导致的营养元素间的相互影响。  【方法】  以一年生枳砧纽荷尔脐橙幼苗为试材进行了砂培试验。以完全营养液为对照 (CK),设置缺氮 (?N)、缺磷 (?P)、缺钾 (?K)、缺钙 (?Ca)和缺镁 (?Mg)处理,测定不同处理脐橙叶片（老叶和新叶）生长指标及矿质元素含量。  【结果】  所有缺素处理均导致叶片叶绿素含量降低,生物量减少,以缺氮处理最为显著。缺氮降低了叶片N、Ca、Cu、Mo含量;缺磷降低了叶片P、K、Mo含量;缺钾降低了叶片K含量;缺钙降低了叶片N、Cu、Zn、Mo含量但增加了P含量;缺镁降低了叶片Ca、Mg、Zn、Mo含量但增加了K含量。以必需矿质元素为变量分别对各处理老叶和新叶进行主成分分析,老叶中第一主成分 (PC1)明显将缺钾处理与其他处理区分开,与对照相比,缺钾老叶离子组成变化为N (?3%)、P (+1%)、K (?71%)、Ca (+11%)、Mg (+39%)、B (+16%)、Mn (+11%)、Fe (+32%)、Cu (?7%)、Zn (+14%)、Mo (?63%);新叶中PC1明显将缺氮处理与其他处理区分开,缺氮新叶离子组成变化为N (?53%)、P (+8%)、K (+7%)、Ca (?14%)、Mg (+11%)、B (+55%)、Mn (+51%)、Fe (?14%)、Cu (?57%)、Zn (+4%)、Mo (?25%)。老叶和新叶中元素含量呈正相关的元素是N-Cu、N-Ca、Mg-Mn和Cu-Mo,呈负相关的是K-Zn。  【结论】  脐橙幼苗老叶对钾的短期缺乏反应最敏感,缺钾会显著降低老叶中K和Mo含量并增加Mg和Fe含量,而新叶对氮素的短期缺乏最敏感,缺氮显著降低新叶中N、Ca、Cu和Mo含量。短期缺少P、Ca和Mg对脐橙幼苗叶片中的养分含量影响较小。     

Aerial accumulation and partitioning of nutrients by hard red spring wheat

Abstract

Periods of maximum hard red spring (HRS) wheat (Triticum aestivum L.) nutrient demand need to be determined in order to develop best nutrient management practices, and to provide data for nutrient uptake modeling. Aerial (aboveground biomass) whole plant samples of irrigated HRS wheat were collected from the field at 16 growth stages and separated into leaves, stems, heads, and grain for dry matter determinations and analyzed for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), chloride (Cl), zinc (Zn), manganese (Mn), iron (Fe), and copper (Cu) concentrations. Accumulation curves were computed for each plant part for the growing season from compound cubic polynomial models based on accumulated growing degree units (GDUs). Total aerial accumulations of dry matter, N, P, K, Ca, Mg, S, Cl, Zn, Mn, Fe, and Cu were 14400, 116, 30.8, 103, 9.2, 9.3, 15.2, 32.3, 0.18, 0.58, 2.05, and 0.045 kg/ha, respectively. Grain at maturity accumulated greater than 78% of the total aerial N, P, and Zn, while it contained less than 20% of the aerial accumulated K, Ca, Cl, and Fe. Nitrogen and Fe were rapidly accumulated near 200 GDU, while P, K, Ca, Mg, S, Cl, Zn, Mn, and Cu were most rapidly accumulated near 600 GDU. Accumulation rates were 183, 2.9, 0.90, 0.72, 0.008, 1.41, 0.29, and 0.12 kg/ha/d for dry matter, N, P, K, Ca, Mg, S, and Cl, respectively, and 136, 1.7, 0.48, 0.13, 0.004, 0.78, 0.20, and 0.02 g/ha/d, respectively, during grainfill. This plant information suggests the timing of in‐season nutrient applications and, when integrated with other agronomic practices, could improve overall nutrient management for HRS wheat in the northern Great Plains.     

Accounting Spatial Variability of Soil Properties and Mapping Fertilizer Types Using Geostatistics in Southern Ethiopia

This study assesses soil spatial variability and maps fertilizer types using geostatistics. A total of 789 soil samples were collected from Wolaita area, Southern Ethiopia. Ordinary kriging was employed. The result considering coefficient of variation exhibited diverse soil variability (10% to 236%). Exponential semivariogram model described spatial structure of organic carbon (OC), total nitrogen (N), phosphorus (P), magnesium (Mg), boron (B), iron (Fe), zinc (Zn), cation exchange capacity (CEC) and potassium(K)/Mg. Semivariogram model was spherical for pH, calcium (Ca), manganese (Mn), and Gaussian for sulfur (S) and K. Spatial dependence was strong (Cu, Fe and Zn), moderate (pH, OC, N, S, Ca, Mg, B, Mn and CEC), and weak (P and K). Autocorrelation was between 276 and 15,118 meters. Overall, 46% of nutrients (N, P, K, S, B, and Cu) obtained from soil were deficient. Thus, for site-specific nutrient interventions, three fertilizer types (NPKSBCu, NPSBCu, and NPKSB) are suggested.     

河北省主栽山药品种矿质养分累积及矿质营养品质差异

  【目的】  比较河北省主栽山药品种的矿质养分累积特性及营养品质的差异,以期为山药生产提质增效制定科学的养分管理措施。  【方法】  田间试验在河北省蠡县进行,供试山药(Dioscorea oppositifolia L.)品种包括棒药、大和白玉、紫药和小白嘴,山药4个品种的施肥量和施肥方法均一致。在成熟期,取样测定了山药地上部、根茎生物量,以及9种矿质元素(氮、磷、钾、钙、镁、铁、锰、铜和锌)含量和累积量。  【结果】  4个主栽山药品种根茎的鲜生物量表现为大和白玉>棒药>紫药>小白嘴,而干生物量表现为紫药>大和白玉>小白嘴>棒药。大和白玉根茎的氮、钙、镁、锰、铜、锌累积量最高,且钾、钙、镁、锰、铜、锌分配系数最高,紫药根茎的磷、钾累积量最高,且氮分配系数较高,磷分配系数最高,棒药根茎的铁累积量及分配系数均为最高。4个山药品种形成1000 kg产量对大量营养元素的需求量均表现为钾>氮>磷,对中量营养元素的需求量均表现为镁>钙,对微量营养元素的需求量均表现为铁>锌>锰>铜。以《中国食物成分表》(标准版)中山药的9种矿质营养品质指标作为参比,对4个供试山药品种的9个矿质营养品质指标进行主成分分析,提取出特征值大于1的主成分3个,累计贡献率为96.77%。其中,第1主成分贡献率为56.45%,主要受钾、锌的影响;第2主成分的贡献率为29.09%,主要受镁、锰的影响;第3主成分的贡献率仅为11.22%,主要受铁的影响。矿质营养品质综合评价结果为大和白玉最优,其次是棒药,小白嘴和紫药分列第3和第4位,但4个品种矿质营养品质均优于《中国食物成分表》(标准版)中的山药品质。  【结论】  大和白玉为矿质营养品质最优品种,且为高锌品种,棒药为高钙、铁品种,土壤中钾、镁、铁、锰和锌含量是影响山药根茎矿质营养品质差异的主要元素。山药生产中,矿质肥料的施用要考虑土壤中矿质元素含量与不同品种的矿质元素需求,进行科学的养分管理,以进一步提升山药矿质营养品质。     

Comparison of major and trace element concentrations in Danish greenhouse tomatoes (Lycopersicon esculentum Cv. Aromata F1) cultivated in different substrates

The concentration of major and trace elements was determined for tomato (Lycopersicon esculentumcv. Aromata F1) fruits grown in three different substrate systems. The systems were soil and rockwool irrigated with a normal nutrient solution and rockwool irrigated with a nutrient solution with elevated electrical conductivity (EC). At three harvest times, tomato fruits were analyzed for Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Sr, and Zn by ICP-AES and for Cd, Cr, Mo, Ni, Pb, Sn, and V by HR-ICPMS. The concentrations of Ca, Cd, Fe, Mn, Mo, Na, Ni, Sr, and Zn were significantly different (p < 0.05) for tomato fruits grown on the different substrates. Between the harvest times different levels (p < 0.05) were shown for Ca, Cd, Fe, Mn Na, Ni, Sr, Zn Cu, K, Mg, P, Sn, and V. The concentration of Cd was >15 times higher and the concentration of Ca was 50-115% higher in soil-grown fruits than in rockwool-grown fruits. Principal component analysis applied on each harvest split the data into two groups. One group includes soil-grown fruits, and the other group includes rockwool-grown fruits with the two different nutrient solutions.     

EFFECT OF CITRUS ROOTSTOCKS ON LEAF MINERAL COMPOSITION OF ‘OKITSU’, ‘CLAUSELLINA’, AND ‘SILVERHILL’ MANDARIN CULTIVARS

Citrus performance is strongly related with rootstock. This study was conducted to investigate leaf nutrient contents of ‘Okitsu’, ‘Clausellina’ and ‘Silverhill’ mandarin cultivars budded onto sour orange, ‘Carrizo’ and ‘Troyer’ citrange rootstocks in Dörtyol, Turkey in 2004 and 2005. The maximum nitrogen (N), potassium (K), and copper (Cu) contents were determined for ‘Clausellina’; phosphorus (P) for ‘Okitsu’; and sodium (Na) for ‘Silverhill’. Calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), and zinc (Zn) uptake were similar for the mandarin cultivars. ‘Carrizo’ citrange at N, K, Mg, Mn, and Cu uptake; ‘Troyer’ citrange at N, P, K, and Fe uptake; and common sour orange at Ca, Zn, and Na uptake was superior on the other rootstocks. It was observed that ‘Carrizo’ and ‘Troyer’ citrange rootstocks had advantages over sour orange in nutrient uptake. Thus, growth performance, yield, and quality parameters considered, ‘Carrizo’ and/or ‘Troyer’ citranges could be suggested as rootstocks for the studied mandarin cultivars under similar ecological conditions.     

The Effect of Bat Guano Applied to the Soil in Different Forms and Doses on Some Plant Nutrient Contents

This research was conducted for the purpose of determining the effects of bat guano on plant nutrient contents in the soil and in lettuce (Lactuca sativa L.) during the spring of both 2014 and 2015 with three replications according to randomized blocks experiment design. Bat guano was applied to the soil in two different forms; According to the results organic matter, P, Cu and Mn amounts in the soil were found to be statistically significant and increased compared to the control. Likewise, in the application of bat guano dust, organic matter, P and Mn amounts in the soil were found to be statistically significant and increased compared to the control. In lettuce, N, K, Mg, Fe, Cu, Zn and Mn amounts in the application of bat guano powder and K, Ca, Mg, Fe, Zn and Mn amounts in the application of bat guano dust were found to be statistically significant.     

中文参考篇名: 发育于第四纪红壤的某新垦红壤旱地的肥力特征与肥料需求

A series of field experiments from 1990 to 1994 in Yingtan, Jiangxi Province, were conducted on an upland red soil derived from Quaternary red clay which had been reclaimed three years before the experiments, in order to study the fertility characteristics and fertilizer requirements of the newly reclaimed soil. The field experiments included that on nutrient characteristics and fertilizer effect, that on K-supplying potential and K-Mg relationship, that on fertilization rates of K and N, etc. The newly reclaimed upland soil was low in both N and P, and its responses to nitrogen and phosphate application were very significant. The K-supplying potential was also low, so the soil was highly responsive to K fertilizer. The effect of Ca and Mg fertilizers was not so great for the reason that certain amounts of Ca and Mg were incorporated into the soil through application of calcium magnesium phosphate during land leveling before the experiments. Among the four micronutrients, B, Mo, Zn and Cu, B had the greatest effect on the soil. The fertilizer requirements of the soil were in an order of P and N > K > lime and B > Mg > Mo, Zn and Cu. Eight crops tested had different fertilizer-requiring characteristics. Rapeseed was very sensitive to P and B fertilizers. Barely was especially sensitive to P and lime and it also responded to B, Mo, Zn and Cu. And sweet potato was especially sensitive to K.     

Diagnosis of Nutrient Constraints in Citrus Orchards of Humid Tropical India

ABSTRACT

Citrus growing in humid, tropical India is concentrated in east to northeast India. The region is well known for large-scale commercial cultivation of Citrus reticulata Blanco, cultivar ‘Khasi,’ mandarin. Extensive surveys were conducted covering as many as 108 orchards from 52 locations representing eight states, namely West Bengal, Sikkim, Assam, Meghalaya, Tripura, Mizoram, Arunachal Pradesh, and Manipur. Expressed in milligrams per kilogram, the optimum values for available nutrients in soil were determined to be as: nitrogen (N) (220.8–240.6), phosphorus (P) (21.2–45.6), potassium (K) (252.2–300.8), calcium (Ca) (278.1–318.6), magnesium (Mg) (67.2–92.5), iron (Fe) (82.2–114.6), manganese (Mn) (21.4–32.8), copper (Cu) (0.82–2.62), and zinc (Zn) (2.18–4.22) using multivariate quadratic regression analysis. The corresponding leaf-nutrient values, expressed in percent, were: N (2.23–2.49), P (0.10–0.11), K (1.86–2.12), Ca (2.12–2.32), and Mg (0.28–0.38), and in ppm were Fe (148.2–179.8), Mn (72.2–84.8), Cu (10.4–18.6), and Zn (24.2–38.8). These reference values of soil and leaf analysis were later observed to be well within the range of values obtained for high-performance orchards (45–62 kg tree^?1), confirming the hypothesis that soil fertility and leaf nutrient levels maintained under high yielding orchards could be used provisionally as nutrient diagnostics. Nutrient constraints in the form of N, P, Ca, Mg, Cu, and Zn were identified using these diagnostics, which deserve a place in a fertilizer program of mandarin orchards of the region to obtain sustainable optimum fruit yield.     

Pecan leaf analysis: I. Varietal,fertilizer, and seasonal effects

Abstract

Differences in elemental content of pecan [Carya illinoensis (Wang.) K. Koch] leaves among cultivars were found for N, P, K, Ca, Mg, Mn and Zn. Of the 7 elements studied, only leaf K indicated a date by cultivar interaction. Differences in leaf K among cultivars became greater as the season progressed. Increasing rate of application of N‐P‐K fertilizer increased leaf N, Ca, Mn, and Al, but had very little or erratic effect on leaf P, K, Fe, B, Cu, Zn, and Sr. There were very few consistent significant fertilizer rate by date interactions for the 13 elements tested. Seasonal trends for element leaf contents from mid‐May through October were generally downward for N, upward for Ca, Mn, Fe, B, Cu, Al, and Ba and changed very little for Mg, Zn, and Sr. Leaf P and K responses to sampling date varied with year. Large year to year variations in leaf trends over dates suggests difficulty in selecting a period for leaf sampling where little change in leaf levels consistently occurs.     

巨桉人工林叶片养分交互效应

在四川巨桉栽培区设立了60个标准地,采用相关分析和矢量诊断法进行分析,以了解巨桉人工林养分的相互作用关系。结果表明,巨桉人工林叶片的养分交互作用较为复杂。N可促进P、K、Ca、Mn等的吸收,但易受到Fe、Zn、高Ca、高Mg的拮抗,而且高N抑制了Mn的吸收;P可促进K、Mg、Mn等的吸收,但易受Zn、Fe、高Mn、高K、高Ca、高Mg的拮抗,而高浓度的P将抑制K、Zn、Fe等的吸收;K对其他养分元素均没有明显的促进作用,但高浓度K限制P的吸收;Ca、Mg之间可相互促进吸收。同时,低浓度的Ca和Mg有利于Fe、Zn的吸收,高浓度的Ca和Mg将对N、P、Fe、Mn、S、B等养分产生拮抗,限制吸收;S可促进Zn的吸收,但易受高Ca、高Mg拮抗;Cu、Zn、Fe、Mn之间主要以拮抗为主。B相互作用较少,对其他养分几乎没有明显的促进作用。     

Seasonal dynamics of mineral nutrients by walnut tree fruits

Walnut (Juglans regia L.) tree fruit showed after the endocarp lignification a fast growing stage during which fresh and dry weights increased abruptly. From the beginning of fruit ripening and during the fast sperm growing stage, fresh weight started to decrease while dry weight continued to increase with a reduced growth rate. Dry weights increased in sperm and decreased in exocarp‐mesocarp tissues during the fast sperm growing stage. The material exit from pericarp tissues was completed in the ripe fruit. By contrast, fresh weight continued to decrease in the tissue. Patterns of nutrient accumulation per fruit increased continuously during the fruit growth period. The observed reductions of nutrient accumulations for total nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) in the fruit individuals during the very late fruit stage after fruit ripening, and in conjunction with the pericarp tissues senescence, are supposed to represent mineral nutrient returns from the ripe fruit. Patterns of total N, P, Mg, Fe, and Zn accumulations increased in the exocarp‐mesocarp tissue during the slow sperm growing stage and decreased during the fast sperm growing stage. Potassium accumulation in the tissue increased continuously up to the fruit ripening time. Calcium, Mn, and Cu increased continuously. Patterns of all nutrients in endocarp tissue increased during the slow sperm growing stage and decreased at the fast sperm growing stage. In the sperm tissues, total N, P, Mg, and Ca accumulations increased during the sperm development and slightly decreased in a late stage. The increasing trend of Ca accumulation was temporarily interrupted during the fast sperm growing stage. Iron, Mn, Cu, and Zn accumulations showed no reductions at all. Potassium accumulation was drastically restricted in the tissue with the approach of fruit ripening. Sperm tissues are extraordinary rich in mineral nutrients. Sperm total N, P, Mg, Mn, Zn, Cu, and Fe accumulations represented the 98.1%, 88.2%, 59.2%, 81.5%, 72.3%, 65.6%, and 52.5% of the total nutrients accumulation in the fruit, respectively. Sperm K and Ca accumulations represented only the 13% and 11.6%, respectively. Exocarp‐mesocarp K, Ca, and Mg accumulations represented the 76%, 72% and 37.1% of the total nutrients accumulation in the fruit individual, respectively. Total N and P accumulation in the tissue were detected in very low levels 1.3% and 7%, respectively. Iron, Cu, Zn, and Mn accumulations were detected in the same tissue in ratio values of 27.5%, 22%, 5.4%, and 11%, respectively. Macro‐ and micro‐nutrient accumulations of the endocarp tissues were detected in the lower levels as compared to the other fruit tissues. The estimated values of mineral nutrient returns from the mature fruit individuals were 2.8% for total N, 13% for P, 16.5% for K, 23% for Ca, 12% for Mg, 28.5% for Fe, and 21% for Zn. Manganese and Cu showed no returns at all. The estimated nutrient returns from the sperm tissues were 60% for total N, 67% for P, 22% for K, and 50% for Mg of the total returned nutrient from the fruit individual. The estimated nutrient returns from exocarp‐mesocarp were 100% for Zn, Fe, and Ca, 50% for Mg, 78% for K, 33% for P, and 40% for total N. Calcium, Fe, Mn, Cu, and Zn in the sperm and Mn and Cu accumulations in pericarp tissues showed no returns at all. A restricted nutrient diffusion from exocarp‐mesocarp and sperm tissues to the endocarp tissues is supposed to be possible. These results suggested a pericarp tissue behaviour similar to the old senescing leaves.