Relationships between leaf and fruit minerals and fruit quality attributes of apples grown under northern conditions

Field experiments were conducted during 1994–1995 in seven apple (Malus spp.) orchards located in the southwest of Finland (the mainland and the Åland Islands). The cultivars were ‘Transparente Blanche’, ‘Samo’, ‘Melba’, ‘Raike’, ‘Red Atlas’, ‘Åkerö’, ‘Aroma’, and ‘Lobo’. Leaf samples from branches bearing fruits (BF) and not‐bearing fruits (BNF) were collected two times during the growing seasons. Fruit samples were picked about one week before commercial maturity. Macronutrient concentrations in fruits and leaves, fruit diameter and juice pH, titratable acidity (TA) and soluble solids concentrations (SSC) were determined. Leaf nitrogen (N), phosphorus (P), and potassium (K) were higher, but calcium (Ca) and magnesium (Mg) were lower in BNF. Branch types (BF and BNF) were closely related in leaf N, P, and Ca, but not in leaf K and Mg at the first sampling time. Fruit N, P, K, and Mg were closely related to each other but not to fruit Ca. Mean fruit N and Ca and leaf P and Mg were low compared with the recommended levels. Relationships between fruit and leaf nutrient concentrations were found only in P and Mg. Fruit diameter increased and juice SSC decreased with increasing leaf N concentration. Fruit P declined with increasing fruit diameter and juice TA increased and SSC/TA decreased with increasing leaf P and Ca concentrations.     

Einfluß exogener und endogener Faktoren auf den Calciumgehalt von Paprika- und Bohnenfrüchten

Effect of external and internal factors on the calcium content of paprika and bean fruits In water culture experiments with paprika and bean plants the effect of Ca supply, transpiration and growth rate on the Ca content of the fruits has been studied. A 10-fold increase in Ca supply only slightly increased the Ca content. The Ca content of the paprika fruits was increased considerably at high transpiration rates of either the whole shoot or the single fruit. High transpiration also increased the Mg content but had no effect on the K content. In bean high transpiration rates only increased the Ca content in the early stages of fruit development. The ratio of Ca translocation versus water loss by transpiration sharply declined during fruit growth in both species. In paprika the highest ratio (μg Ca/ml) in the fruits corresponded with the ratio in the leaves. In bean fruits, however, this ratio distinctly exceeded that of fully developed leaves. At high transpiration rates of the shoot 20% of the Ca (⁴⁵Ca) injected into the fruit were translocated out of the fruit. At low transpiration rates of the shoot the corresponding value was below 1%. Most of all the growth rate of the fruits affected the Ca content. With increasing growth rate the Ca transport into the fruits was hardly altered which in turn led to a sharp decrease of the Ca content per unit dry weight. The results support the idea of the Ca transport into the fruit via the xylem. This Ca transport — i.e. also the Ca content of the fruit — is regulated and is also to be influenced by direct or indirect alterations of the water transport in the xylem.     

Effects of Antitranspirant Spray and Potassium: Calcium: Magnesium Ratio on Photosynthesis,Nutrient and Water Uptake,Growth, and Yield of Sweet Pepper

Sweet pepper plants (Capsicum annuum L.) were cultivated hydroponically under different nutrient cation ratios at both high potassium (K)/calcium (Ca) (12:2) or magnesium (Mg)/Ca (4:2) ratios, compared with half strength Hoagland's solution (K:Ca:Mg; 3.5:2:0.5). Additionally, antitranspirant (Pinolene) was sprayed every fortnight to the aerial part of the plant at 1% (v/v). The antitranspirant (AT) did not affect dry weight accumulation in the leaves, stems, roots, total plant leaf area, or leaf dry weight percentage. Net carbon dioxide (CO₂) assimilation was not impaired by the AT but the water uptake was reduced significantly independent of the nutrient solution used. The AT did not affect the cation uptake but high Mg significantly reduced Ca concentration in leaves, stems, and fruits, whilst high K had an effect only in old leaves and fruits. The AT reduced fructose and glucose concentration in the leaves but no effect was found in the fruits. Fruit yield was not affected by AT, but it was increased when plants were grown with high Mg/Ca. The percentage of blossom-end rot was reduced with the AT, whilst it was increased with the solutions having high K/Ca or high Mg/Ca. The AT significantly reduced fruit firmness in high Mg/Ca and control solution but no effect was found for fruit color, shape index, total soluble solids, or pericarp thickness.     

柑桔皱皮果与果皮及其细胞壁矿质元素关系的研究

对红 1 7甜橙、红江橙及红江橙正常果与皱皮果、红江橙阴面果与阳面果的果皮及其细胞壁N、P、K、Ca、Mg的含量进行了分析 ,探讨这些矿质元素与柑桔成熟期皱皮果形成的关系。结果发现红 1-7甜橙皱皮果发生率较低 ,仅为 7.34% ,而红江橙皱皮果发生率高达 28.06% ;皱皮现象 86%以上出现在果实的阴面果皮。果皮N、P含量与柑桔皱皮果的形成没有相关性 ,K在皱皮果中的含量比正常果高 ,而在阳面果皮比阴面果皮高 ;Mg在皱皮果和阴面果皮及其细胞壁的含量都比在正常果和阳面果皮稍低 ,但Mg的含量与皱皮果率的相关性不显著 ;Ca在正常果和阳面果皮及其细胞壁的含量都明显高于皱皮果和阴面果皮 ,皱皮果率与Ca的含量呈显著的负相关     

A NEW STRATEGY TO ENRICH CALCIUM NUTRITION OF FRUIT: SYNERGISTIC EFFECTS OF POSTHARVEST FOLIAR CALCIUM AND BORON SPRAYS

The objective of the study is to investigate the role of calcium (Ca) and boron (B) synergy in higher maintenance of Ca in fruit buds during senescence. To study the hypothesis, an experiment was conducted for two years in two ‘Starking Delicious’ apple (Malus domastica Borkh.) orchards established on seedling rootstocks in Banaz, Usak, Turkey. Treatments composed of postharvest foliar sprays of Ca at rate of 15.13 kg h^?1, B at rate of 2.47 kg h^?1 and their combination (Ca+B) compared with control trees sprayed with water. Fruiting spurs, flower ovaries, young and mature fruits were sampled and analyzed for their Ca, B, potassium (K) and magnesium (Mg) contents. Fruit were stored for six months and quality attributes were studied. Results put forth that Ca+B treatments significantly increase fruit Ca and B concentrations and firmness. The results displayed that postharvest B spray improves Ca nutrition of fruits through synergism of Ca+B on Ca translocation.     

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。     

Fruit nutrient accumulation of four orange varieties during fruit development 1

Evaluation of nutrient accumulation trends in fruit during fruit development and nutrient status in the leaves are important components defining nutrient requirements. Such nutrient demand should be met by nutrient supply in order to develop optimal rate and timing of fertilizer application. In a 3‐year study the citrus (orange) varieties, ‘Valencia’, ‘Parson Brown’, ‘Hamlin’, and ‘Sunburst’ were fertilized with either 168, 224, or 280 kg N ha^‐1 yr^‐1 as a broadcast application of N:P:K dry soluble granular fertilizer. These rates did not significantly affect the fruit nutrient status, juice quality, or nutrients concentrations in the spring flush. The concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) in the fruit decreased with their enlargement during June through November. However, micronutrient concentrations in the fruits increased from June through August or September and then decreased. Fruit dry weight was greatest in ‘Valencia’ followed by ‘Hamlin’, ‘Parson Brown’, and ‘Sunburst’ varieties. Soluble solids concentration (SSC) were higher in ‘Valencia’ and ‘Sunburst’ fruit than in the other two varieties. Other juice quality parameters were not significantly different among the varieties. This study indicated non‐significant influence of fertilizer rates on concentrations of various mineral elements in 6‐month‐old spring flush with most of those concentrations within the optimal ranges.     

Greenback disease and mineral content of tomato fruit

The hypothesis that a relatively high Ca content in the fruit associated with relatively low K/Ca, K/Ca and K + Mg/Ca ratios are indicators of a slow ripening and a delayed senescence has been confirmed by analysing the sound and greenback fruits of two tomato varieties. The elemental changes characterizing a retardation of ripening are associated with the greenback disorder not only in the diseased calyx end of the fruit but also in the apex end where the fruit seems to ripen and colour uniformly.     

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。     

Potassium inhibition of calcium and magnesium accumulation in roots of intact maize seedlings

The effects of solution potassium (K) on the accumulation of magnesium (Mg) and calcium (Ca) in roots was assessed with 7‐day‐old corn (Zea mays L.) seedlings. Root accumulation of Ca and Mg was studied in replacement type experiments, i.e. the ratio of Ca to Mg was altered but the concentration of Ca plus Mg was kept constant at 2 mM. Concentrations of Ca in the tissue after 12 h exceeded that of Mg, except when Mg comprised over 85% of the divalent cations in the uptake solution. The addition of 0.1 mM K to the Uptake solutions significantly altered the accumulation of Ca and Mg. The concentration of Mg was affected more than that of Ca. The relative effects of solution K on Mg and Ca accumulation in roots could be explained by comparing the relative acid‐base characteristics of the metals.     

Possibilities and limitations of utilizing 28Mg for studying Mg‐specific problems in higher plants

The possibility of utilizing artifical radionuclides in agricultural biological research enabled studies to be implemented in which the detection sensitivity of the nutrients to be investigated was one to two powers of ten higher than with physicochemical methods. Although usable radionuclides are available for numerous plant nutrients, their radiochemical properties partly restrict their utilization. For example, the relatively short half‐life of ²⁸Mg of 21.3 hours only permits short‐term studies. This is all the more disadvantageous the lower the specific activity of ²⁸Mg is. The ²⁸Mg produced from a lithium target in the experimental reactor Merlin at the KFA Jülich achieves a maximum specific activity of 1 mCi/g Mg. In contrast, specific activities of over 1 Ci/g Mg are achieved in the isochronous cyclotron where ²⁸Mg is generated from an aluminium target. This more or less carrier‐free ²⁸Mg is especially suitable for short‐term studies (minutes or hours) or for problem areas in which the ²⁸Mg uptake rates are very low. It was able to be demonstrated on the basis of autoradiographs that Mg is a relatively mobile nutrient in higher plants and is transported both in the xylem and also in the phloem. Its uptake and transport rate does not only depend on the presence and concentration of competing cations but is also considerably influenced by the type of plant and its nutritional status, especially by its K content. In studies on strawberry plants and grapevines it was demonstrated that the transport rate of Mg in the fruits was in part considerably greater than that of Ca. However, this relative preference for Mg in comparison to Ca largely depends in the case of grapevines on the uptake conditions and the type of application (dipping or trough application). In comparative studies of the leaf uptake of ²⁸Mg it was established that considerably more ²⁸Mg was taken up from ²⁸MgCl₂ than from a complete nutrient solution or leaf dressing solution.     

Effect of sodium arsenite and sodium chloride on bean plant nutrition (macronutrients)

The effects of different levels of arsenic (As) and salinity on bean plant (Phaseolus vulgaris L., cv. Buenos Aires) nutrition were investigated. We studied the processes of absorption and accumulation of macronutrient elements: nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg). The experiment was performed in soilless culture at two levels of As: 2 and 5 mg AsL^‐1 (added as sodium arsenite, NaAsO₂), and three saline levels [only sodium chloride (NaCl) was added]: 1, 2, and 4 dS‐m^‐1. Sodium arsenite and NaCl significantly affected macronutrients allocation within bean plant at concentration levels used in this study. Arsenite depressed K, Na, and Mg concentrations in root, whereas root N, and Ca levels were increased. Nitrogen, P, K, and Na concentrations were significantly higher in As‐stressed plants compared with controls. The addition of NaCl increased Ca concentration in roots and decreased that of K. Salinity tended to increase leaf concentrations of K, Na, Ca, and Mg; whereas leaf N and P levels decreased with increasing salinity.     

Peanut seed size and nutritional calcium requirement

A differential response of peanut (Arachis hypogaea L.) cultivars with varying seed sizes to Ca nutrition has been observed for many years. No satisfactory explanation of why different seed sizes respond differently to Ca nutrition was found. Fruit with a wide range of seed sizes were investigated. Fruit characteristics relating to seed size and Ca content expressed as a concentration and as the total amount in a fruit were compared. Ca content expressed as a concentration showed no relationship to seed size. Utilizing total Ca content in a peanut fruit and its volume, it was shown that large‐seeded fruit needed to transport Ca through a longer soil distance to satisfy the fruit's nutritional need than small‐seeded fruit did. This result does not address any Ca nutritional characteristics internal to a peanut fruit nor does it address any genetic nutritional variables.     

Ammonium reduces growth,fruit yield and fruit quality of watermelon

Watermelon (Citrullus lunatus Thunb.) plants cv ‘Sugar Baby’ were grown hydroponically in a greenhouse under NO₃:NH₄ ratios of 3:1, 1:1, and 1:3. Plants receiving the high ammonium treatment expressed symptoms of NH4‐toxicity and declined rapidly after bloom. Reducing NO₃:NH₄ from 3:1 to 1:1 significantly reduced growth, water use, fruit yield, flesh soluble solids and uptake of NO₃, NH₄, K, Ca and Mg.     

Fruit growth and mineral element accumulation in pacific rose™ apple in relation to orchard management factors and calyx‐end splitting

Abstract

The effect of irrigation and crop load of apple (Malus domestica Borkh cv. Pacific Rose) on the fruit growth and mineral element accumulation was investigated. Fruit growth and changes in the concentration and contents of nitrogen (N), phosphorus (P), calcium (Ca), magnesium (Mg), and potassium (K) in the flesh of Pacific Rose? apple fruit were recorded over a growing season at the Massey University Fruit Crops Units orchard in the 1998–99 crop season. Fresh mass showed a linear growth while fruit diameter followed a curvilinear growth pattern during the growing season. Low crop load significantly increased fruit size, particularly during the final expansion phase, whereas irrigation had little effect on this attribute. Both low crop load and frequent irrigation treatments increased fruit growth rate, but the effect of the irrigation treatments fluctuated considerably during the season. The incidence of frait splitting was detected at about 20 WAFB when the fruit attained an asymmetrical growth in shape (L/D). The concentrations of N, P, Ca, Mg, and K declined throughout the sampling period. There was however, an increase in concentrations of P and K at the last harvest. The quantity of individual nutrient elements accumulated by the fruit showed an increasing trend during the season. Nitrogen accumulation however, reached maximum at 16 WAFB after which it declined until the last harvest. Fruit mineral element analysis of sound and split fruit revealed that split fruit had higher concentrations and contents of Mg and K and lower contents of Ca and P. As a result, the ratios of Ca: Mg and Ca: K were lower in split fruit as compared with sound fruit.     

不同施钙措施对番茄果实钙含量和钙形态的影响

在营养液中加钙及在花期、幼果期分别向花、叶、幼果喷施20mg.L萘乙酸(NAA)+0.5%CaCl2混合液能够显著增加果实钙含量,其中营养液高钙和喷叶处理增钙效果最好,喷幼果和喷花处理也有较明显的效果,3周大果喷钙对果实增钙效果不明显。增钙的同时,不同措施不同程度影响了果实K、Mg、P及某些微量元素的含量。果实增钙主要是增加了果胶酸钙含量,以营养液高钙、喷叶和喷幼果处理增加程度最高;各种施钙措施显著增加了果实Vc含量,降低了可滴定酸度,改善了果实品质。还探讨了不同施钙措施对植株各部位钙含量和果实钙含量的影响机理。     

Phosphorus nutrition of white rose potato in relation to growth and minerals of leaf and root tissues

Abstract

White Rose potato plants (Solanum tuberosum, L.) were grown outdoors, without tuber formation, in a modified Hoagland's nutrient solution with 9 treatments of KH₂PO₄ ranging from 0 to 4.0 mmoles per liter. Deficiency symptoms ranged from very severe to none at harvest after 27 days of growth. Growth of the potato plants increased with increased P supply and was associated with an increased P content of the plant tissues. The critical H₂PO₄‐P concentration at a 10% reduction of top growth, based on a second leaf analysis, was about 1,000 ppm for the petiole and terminal bladelet and about 1,200 ppm for the lateral bladelet, dry weight basis.

Phosphorus nutrition had only a slight effect on the K, Na, Mg and NO₃‐N concentrations of the root tissues but Ca increased as phosphate increased which suggests a calcium phosphate precipitation. Phosphorus stress lowered the K, Na, Ca, Mg and NO₃‐N concentrations of the petiole tissues of the recently matured leaf which suggests that P increases salt accumulation. Phosphorus nutrition had only a slight effect on the concentrations of K, Na, Mg and Ca of the blade tissues of the recently matured leaf but NO₃‐N increased greatly with P supply.     

Effect of preharvest application of calcium on the postharvest physiology of apricot fruit

The effect of preharvest calcium (Ca) foliar application on ethylene (C₂H₄) production, respiratory rate, soluble polyuronides, and fruit firmness of ‘Bebekou’ apricot fruits was determined. The study was carried out in two experimental years, 1991 and 1992. Calcium was applied 21, 17, and 13 days before harvest for 1991 at the concentration of 0.5% calcium chloride (CaCl₂) each time and 16 and 12 days before harvest for 1992 at the concentrations of 0.8 and 0.7% CaCl₂, respectively. Calcium treatment resulted in a 30–76% increase in the Ca content of fruit flesh. Treated fruits had significantly lower C₂H₄ production rates than control during (i) four (1991) or five days (1992) at 21°C out of the 7‐day period examined immediately after harvest, and (ii) one (1991) or two days (1992) at 21°C out of the seven‐day period examined immediately after a 3rd‐ (1991) or 4th‐week (1992) storage period at 0°C. After harvest, Ca‐treated fruits displayed one day delay to reach the peak rate of C₂H₄ production. Respiratory rate was significantly suppressed over a five‐day period at 21°C out of the seven‐day period examined immediately after harvesting. However, after four weeks of storage at 0°C, there was not any significant effect of Ca on the respiratory rate. The respiratory peak rate occurred earlier in the control fruits compared to that of the Ca‐treated fruits at harvest time. Calcium‐treated fruits were about 70% firmer than the untreated ones at harvest time. Furthermore, this difference persisted after four weeks of storage at 0°C. Foliar‐applied Ca produced a 29% decrease in the soluble polyuronide content of the fruits at harvest time, but not after four weeks of storage. Fruit firmness was positively correlated to the Ca content of fruits while the soluble polyuronide content of the fruit was negatively correlated to fruit Ca.     

Ethylene evolution and ammonium accumulation by nutrient‐stressed tomato plants

Environmentally stressed plants frequently have elevated rates of ethylene evolution and high accumulation of free ammonium by their foliage. The objective of this study was to investigate ethylene evolution and ammonium accumulation by nutrient‐deficient and ammonium‐stressed tomato plants (Lycopersicon esculentum Mill. ‘Heinz 1350’ and neglecta‐1) grown in a greenhouse. In soil culture, ‘Heinz 1350’ was more sensitive to ammonium toxicity and had higher ethylene evolution than neglecta‐1. High ethylene evolution corresponded with appearance of ammonium toxicity symptoms in both lines. In sand culture, ‘Heinz 1350’ and neglecta‐1 grown with K, Ca, or Mg deficiency in NO₃ ^‐‐based nutrient solutions had higher ammonium accumulation and higher ethylene evolution than plants grown with complete nutrition. P‐deficient plants had elevated ammonium accumulation but low ethylene evolution. Plants grown on NH₄ ⁺‐based nutrition with pH buffering by CaCO₃ had lower ethylene evolution and lower ammonium accumulation than plants grown in unbuffered solutions but had higher values than plants grown with NO₃ ^‐‐based nutrition. Adequate K nutrition suppressed ethylene evolution and ammonium accumulation for all plants regardless of nitrogen regimes. Ammonium accumulation and ethylene biosynthesis in plants appear to be related processes. They appear to be indicators of stress and may have roles in development of symptoms of nutritional stresses.