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.     

EFFECT OF AUTUMN CALCIUM SPRAY AT A HIGH RATE ON ‘GRANNY SMITH’ APPLE QUALITY AND STORABILITY

The aim of the study was to examine effect of autumn calcium (Ca) spray at a high rate on apple quality and storability. The investigation was carried out during 2005–2006 in Isparta district, Turkey, under semi-arid conditions, on mature ‘Granny Smith’ apple trees/M.9 EMLA, planted at a spacing of 3.5 × 1.5 m on fine-textured soil rich in Ca. The trees were sprayed with Ca in summer and/or in autumn, using organically complexed Ca to avoid possible leaf and fruit injuries. In autumn (10 days before harvest), the trees were sprayed with Ca at a rate of 8 kg ha^?1. In summer, the another trees were sprayed with Ca six times at a rate of 1.5 kg ha^?1 in each measure; the first spray treatment was performed 6 weeks after full bloom, and the others at 7–9 day intervals. The third part of the trees was sprayed with Ca in summer as well as in autumn, at the same terms and rates as given above. Trees unsprayed with Ca served as the control. It was found that Ca sprays in autumn or in summer plus in autumn damaged leaves; however those treatments did not caused defoliation. Calcium sprays had no effect on apple yield, mean fruit weight, fruit skin russeting, and firmness, soluble solids concentration and titratable acidity of fruit at harvest. Fruit flesh Ca concentrations of the control trees were high. However, the highest fruit Ca concentration was recorded on the trees sprayed with Ca in summer plus in autumn. Calcium sprays in summer or in autumn increased fruit Ca concentrations but their effects were weaker than summer plus autumn Ca applications. After 100 days of refrigerated air storage, soluble solids concentration of fruit did not differ between the studied combinations. Only apples sprayed with Ca in summer plus in autumn were firmer and contained more organic acids than the control fruit. During storage, there were neither pathogenic diseases nor physiological disorders. Based on the obtained results we conclude that Ca sprays in summer plus in autumn at high rate can prolong ‘Granny Smith’ apple storage even thought initial fruit Ca concentration is as high as 502–504 mg Ca kg^?1 DW or 84.1–84.8 mg Ca kg^?1 FW.     

Nitrogen Application Rate and the Concentration of Other Macronutrients in the Fruit and Leaves of Gold Kiwifruit

ABSTRACT

Gold kiwifruit (Actinidia chinensis Planch. var. chinensis ‘HORT16A’, marketed as ZESPRI?' ‘HORT16A’) is an important export crop for New Zealand. Nutrient management, including the application of nitrogen (N), for ‘HORT16A’ kiwifruit has mimicked strategies for the green (A. deliciosa ‘Hayward’) cultivar, however, physiological differences between Actinidia species necessitate the development of specific nutrient regimes for ‘HORT16A’ vines. In this trial, all nutrients, except N, were applied at levels comparable to commercial practice. The Control treatment received approximately 145 kg N ha/y, and was based on estimates of total N removed each year in the harvested fruit. The Zero-N treatment vines received all nutrients except N, and the High-N treatment received double the Control, approximately 295 kg N ha/y, for two consecutive seasons. The High-N treatment represents the upper limit of N application practices in commercial ‘HORT16A’ kiwifruit production. Zero-N fruit had higher calcium (Ca) and lower N concentration than High-N fruit in both seasons. Fruit potassium (K) and magnesium (Mg) concentrations were equivalent between these treatments in both seasons. Fruit phosphorus (P) concentration throughout the season was increased in the High-N treatment in both years. Fruit sizes were not different between treatments at final harvest in Year 1, being 130.5 ± 4.13 g, 125 ± 1.49 g, and 125 ± 3.29 g for the High, Control, and Zero-N vines, respectively. Larger fruit were harvested from the High-N vines (125 ± 4.69 g) in Year 2, than from either Control (113 ± 2.03 g) or Zero-N (118 ± 1.03 g) vines. Percent fruit dry matter (DM) content was higher in the Zero-N fruit (17.2 ± 0.06, 17.2 ± 0.06, and 16.8 ± 0.14 for Zero, Control, and High-N vines) at final harvest in Year 1. But values of fruit DM for all treatments were similar in Year 2 in spite of fruit size differences between treatments. Fruit DM for all treatments was slightly higher in Year 2 than in Year 1. Differences in fruit mineral concentration and fruit maturity at harvest may have contributed to increased incidence of low temperature breakdown (LTB) in the High-N fruit in Year 1. In Year 2, when fruit DM was higher in all treatments, yellow coloration was more developed. Total fruit N concentration was lower in Year 2 for all treatments than in Year 1, and LTB was minimal and not different between treatments.

Leaves from Zero-N vines had reduced N in both years compared with Control and High-N vines. In contrast, leaf Ca and Mg concentrations were reduced in High N-vines, compared with values recorded in Zero-N vines in both seasons. Leaf K concentrations were comparable between treatments in both seasons. Leaf sulfur (S) concentration was reduced under the High-N treatment, and leaf P levels were increased under the High-N treatment in both years.

These data demonstrate that N application influences the uptake and accumulation of other mineral elements in ‘HORT16A’ kiwifruit. In order to encourage desirable nutrient concentrations in both the fruit and leaves of ‘HORT16A’ kiwifruit, a reduction in N applied is suggested, and this would have little or no detrimental effect on vine performance over two seasons. Reduced N application will also reduce nitrate leaching which is estimated at 39 kg N ha/y under the Control treatment.     

Calcium Nutrition of Peanut Grown in Solution Culture. I. Genetic Variation in Ca Requirements for Vegetative Growth

ABSTRACT

Calcium (Ca) deficiency is an important problem in peanut (Arachis hypogaea L.) production, with lines from the sub-species A. hypogaea hypogaea (Virginia type) being considered more susceptible to Ca deficiency than those of A. hypogaea fastigata (Spanish and Valencia types). Fifteen peanut lines comprising five Virginia bunch, one Virginia runner, six Spanish, two Valencia types, and one Valencia × Spanish cross were grown for 30 d in continuously flowing solution culture at constant external Ca concentrations ranging from 9 to 2500 μM. Two lines required <9 μM Ca for near-maximum growth, whereas 5 lines required 15–20 μM, six lines required 25–50 μM, and two lines required >75 μM Ca for maximum growth. The Ca concentration in the youngest fully expanded leaves required for maximum growth also differed considerably among the lines, ranging from <5.7 g kg^?1 in ‘SH-2’ to 17.3 g kg^?1 in ‘Red Spanish’). The differences in solution and tissue Ca requirement for growth did not coincide with the broad botanical groupings despite that Virginia type peanut lines had consistently lower Ca concentrations in youngest fully expanded leaves than Spanish or Valencia lines at all solution Ca concentrations. Leaf magnesium (Mg), potassium (K), phosphorus (P), iron (Fe), and manganese (Mn) concentrations in the leaves decreased as the solution Ca concentration increased and it seemed probable that growth reductions observed at above-optimum Ca concentrations were due to induced deficiencies of P, Mg, or possibly Fe.     

The effect of calcium spray on leaf and bract distortion,bound:unbound calcium ratio,and calcium distribution in two poinsettia cultivars

To determine if direct Ca sprays could affect the distribution and binding of Ca in the leaves and the severity of leaf/bract distortion in two varieties of poinsettia (Euphorbia pulcherimma Willd.), we applied either 100 mg.l^‐1 or 400 mg.1^‐1 of Ca either one time or weekly to leaves of distortion‐ susceptible ('V‐14 Glory') and nonsusceptible ('Annette Hegg Dark Red,’ AHDR) cultivars. Only weekly spraying with 400 mg.l^‐1 Ca reduced distortion in V‐14 plants, compared to controls or AHDR plants. Both bound and unbound Ca concentrations were higher in AHDR leaves than in V‐14 leaves, but these differences were not correlated with distortion severity. EDX analysis demonstrated that distorted regions of V‐14 leaves and bracts had lower Ca concentrations than did undistorted regions or AHDR leaves; weekly spraying with 400 mg.l^‐1 Ca produced relatively uniform leaf Ca distribution in V‐14 leaves. Localized Ca deficiencies appear to produce the bract/leaf distortion in ‘V‐14 Glory’ plants, and these deficiencies can be partially overcome by weekly Ca spray applications.     

Seasonal Changes of Mineral Nutrients in Fruit and Leaves of ‘Newhall’ and ‘Skagg's Bonanza’ Navel Oranges

In southern Jiangxi province of China, ‘Newhall’(Citrus sinensis Osbeck) navel orange presented a conspicuous symptom of boron (B) deficiency in mature leaves, whereas B deficiency symptoms were not manifested on ‘Skagg's Bonanza’(C. sinensis Osbeck) navel orange. In this study, changes in concentrations of B, calcium (Ca), potassium (K), magnesium (Mg), manganese (Mn), and zinc (Zn) were comparatively investigated in the structural parts of the fruit (rind and pulp) and leaves (old leaves from last season and spring-flush leaves from current year) of ‘Newhall’ and ‘Skagg's Bonanza’ navel orange during the growing season. Two peaks of B concentrations were observed in the rind of the two cultivars during fruitlet growth and fruit enlargement, respectively. Boron concentrations were relatively high in the rind during fruitlet growth, and then decreased in both rind and pulp, whereas, during middle and late fruit enlargement significant increases were found for B in both rind and pulp of the two cultivars. Boron concentrations in old leaves of ‘Newhall’ decreased progressively and remained relatively low, whereas that of ‘Skagg's Bonanza’ was relatively high and changed slightly as the season progresses. Both Ca and K concentrations were above the critical threshold values, while their dynamics were reverse to that of B in fruit and leaves during certain times. Old leaf Mg concentrations of samples at 140 days after full bloom from the two cultivars and spring-flush leaves from ‘Newhall’ were below the threshold limit for sufficiency. In addition, Mg in old leaves was much lower from ‘Newhall’ than from ‘Skagg's Bonanza’. Spring-flush leaf concentrations of Mn and Zn and Mn concentrations in old leaves from ‘Newhall’ were relatively lacking during middle and late season, which accelerated the occurrence of B deficiency symptoms on mature leaves of ‘Newhall.’     

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.     

Effect of Preharvest Sprays of Calcium on Cracking and ‘Schattenmorelle’ Sour Cherry Fruit Quality Harvested Mechanically

The aim of the study was to examine effect of preharvest sprays of calcium (Ca) in the form of Ca-chloride (CaCl₂), Ca-nitrate [Ca(NO₃)₂], or a mixture of Ca-formate, Ca-acetate, CaCl₂, and Ca(NO₃)₂ on cracking and quality of ‘Schattenmorelle’ sour cherry fruit harvested mechanically. The experiment was conducted in 2008–2009 at a commercial orchard in central Poland. Mature trees grew on a coarse-textured soil poor in organic matter, at a spacing of 4.0 × 1.5 m. The spray treatments of Ca were performed at 7-day intervals, starting 28 days before harvest, at the rates of 5.0–5.6 kg Ca ha^?1 per season. The trees sprayed with water were treated as the control. Fruit were harvested mechanically when peduncle-fruit detachment force dropped below 3 N. The results showed that preharvest Ca sprays caused no leaf damage. This measure did not affect yield, mean fruit weight, soluble solids concentration and titratable acidity of fruit, and weight loss of fruit during 24 h after harvest. Fruit sprayed with Ca had improved status of this nutrient, and were less liable to juicy leakage from the stem scar, rain-induced cracking, and preharvest decay caused by Glomerella cingulata. The above effects of Ca sprays did not depend on the tested material. It was concluded that preharvest sprays of Ca as CaCl₂ and/or Ca(NO₃)₂ should be recommended in ‘Schattenmorelle’ sour cherry orchards to reduce fruit losses resulting from rain-induced cracking, leakage of juice, and the incidence of cherry bitter rot.     

The effect of calcium spray on leaf and bract distortion,bound:Unbound calcium ratio,and calcium distribution in two poinsettia cultivars

To deteimine if direct Ca sprays could affect the distribution and binding of Ca in the leaves and the severity of leaf/bract distortion in two varieties of poinsettia (Euphorbia pulcherimma Willd.), we applied either 100 mg.l^‐1 or 400 mg.l^‐1 of Ca either one time or weekly to leaves of distortion‐ susceptible ('V‐14 Glory') and nonsusceptible ('Annette Hegg Dark Red,’ AHDR) cultivars. Only weekly spraying with 400 mg.l^‐1 Ca reduced distortion in V‐14 plants, compared to controls or AHDR plants. Both bound and unbound Ca concentrations were higher in AHDR leaves than in V‐14 leaves, but these differences were not correlated with distortion severity. EDX analysis demonstrated that distorted regions of V‐14 leaves and bracts had lower Ca concentrations than did undistorted regions or AHDR leaves; weekly spraying with 400 mg.r¹ Ca produced relatively uniform leaf Ca distribution in V‐14 leaves. Localized Ca deficiencies appear to produce the bract/leaf distortion in ‘V‐14 Glory plants, and these deficiencies can be partially overcome by weekly Ca spray applications.     

Lime,molybdenum, and cultivar effects on molybdenum deficiency of poinsettia

Poinsettia (Euphorbia pulcherrima Willd. ex Klotz) cultivars ‘Annette Hegg Brilliant Diamond’ (AH), ‘Gutbier V‐14 Glory’ (GG), and ‘Eckespoint C‐1 Red’ (ER) were grown in a peat‐perlite potting medium to study lime and Mo effects on the occurrence of Mo deficiency. Two rates of dolomitic limestone, 0 and 3 kg/m³of growing medium, and weekly applications of micronutrient solutions containing 0.0 or 1.0 ppm Mo were made in factorial combination. Lime, Mo, or both prevented Mo deficiency symptoms in all cultivars. Without both lime and Mo, Mo deficiency symptoms appeared on AH and GG, but not on ER. Lime and/or Mo reduced NO₃‐N content, increased Mo content and increased nitrate reductase enzyme activity (NRA) in the upper recently matured leaves of all cultivars. Lime and Mo interacted to affect these parameters in all cultivars. Comparing the three cultivars without both lime and Mo, NO‐‐N content was lowest and NRA highest in ER. However, the Mo content of ER leaves was equal to or less than that of AG and GG which showed Mo deficiency symptoms.     

Dry Matter and Nutrient Partitioning of Selected Pineapple Cultivars Grown on Mineral and Tropical Peat Soils

The pineapple cultivars ‘Moris’ (Queen cultivar), ‘N‐36’ (‘Sarawak’ × ‘Gandul’ hybrid), ‘Gandul’ (Singapore Spanish cultivars), and ‘Josapine’ (‘Singapore Spanish’ × ‘Smooth Cayenne’ hybrid) are mostly grown on peat soils in Malaysia, whereas ‘Sarawak’ (‘Smooth Cayenne’ cultivar) is more commonly grown on mineral soils. To obtain good yields of fruit of high quality, it is important to understand the differences in nutrient requirements for these cultivars in the different soils in which they are grown. Therefore, the objectives of the study were to determine the biomass and nutrient partitioning of the different pineapple cultivars and to determine the plant variables affecting fruit yield and quality. Plants of each of the pineapple cultivars were randomly sampled from different locations of the major pineapple‐growing areas in Malaysia. Only plants having A‐grade fruit of marketable quality at harvest were selected. The cultivars and respective field sites were as follows: ‘Sarawak,’ Bukit Tandak farm, Kelantan (5° 55.274′ N, 102° 00.608′ E); ‘Moris,’ ‘N‐36,’ and ‘Gandul,’ Peninsula Pineapple Plantations, Simpang Renggam, Johor (1° 49.909′ N, 103° 14.053′ E); and ‘Josapine,’ Goh Swee Eng Pineapple Farm, Simpang Renggam, Johor (1° 48.441′ N, 103° 11.935′ E). Plants were partitioned into roots, stem, leaves, peduncle, fruit, and crown, and fresh and dry weights were recorded. Total biomasses for the different cultivars were 733.46 ± 22.83 g for ‘Gandul,’ 842.34 ± 43.26 g for ‘N‐36,’ 927.38 ± 53.10 g for ‘Moris,’ 434.77 ± 16.82 g for ‘Josapine,’ and 2446.94 ± 156.00 g for ‘Sarawak.’ Leaves accounted for the greatest proportion of dry matter (48.5%), followed by fruit (22.9%) and stem (21.6%), and a smaller proportion (1.2–2.5%) was roots, peduncle, and crown. The proportions of the dry‐matter accumulation in leaves and stem for the cultivars were 53.5 ± 0.7 and 16.7 ± 0.9% for ‘Gandul’; 45.1 ± 0.5 and 17.7 ± 0.7% for ‘N‐36’; 51.9 ± 1.6 and 16.8 ± 0.6% for ‘Moris’; 56.5 ± 1.0 and 12.0 ± 0.9% for ‘Josapine’; and 54.2 ± 5.1 and 27.7 ± 4.4% for ‘Sarawak.’ The proportion of the macro‐ and micronutrients in pineapple parts differed widely between cultivars. Potassium (K) showed the greatest proportion (7.96 ± 0.6 to 29.73 ± 1.17%) in leaves and (4.46 ± 0.70 to 9.35 ± 0.28%) in fruit followed by nitrogen (N) and phosphorus (P) with lower proportions. Most pineapple cultivars grown showed variation in nutrient‐use efficiency (NUE) with respect to the elements measured with values of <1.0 g dry matter g^?1 nutrient. The NUE values of >1.0 g dry matter g^?1 nutrient were observed for magnesium (Mg) in ‘Gandul’ and ‘N‐36’ and for calcium (Ca) and copper (Cu) in ‘N‐36.’ Total nutrient accumulation in the plant components differed approximately according to their cultivar origins (‘Smooth Cayenne,’ ‘Queen,’ ‘Singapore Spanish’). It is interesting that the results for the ‘Singapore Spanish’ × ‘Smooth Cayenne’ hybrid Josapine were more similar to the ‘Singapore Spanish’ cultivars than being between the parents. Partitioning of biomass and nutrients in pineapple provides a means to categorize them and makes it possible to use a cultivar‐based fertilization program.     

Physiological disorders,bitter rot and other fungal decay of ‘Aroma’ apple fruit stored in controlled atmosphere

Effects of controlled atmosphere (CA) conditions on physiological disorders and fungal fruit decay on apple ‘Aroma’ were investigated. Fruit from three growing seasons were stored at 1% or 2% O₂ (both at 2% CO₂) at either 1°C or 3°C in small research units; controls were kept in the same ventilated rooms at the two temperatures (ambient air). The fruit were removed from storage after four or six months and assessed for fruit decay immediately afterwards and after two weeks at 20°C. Fruit quality parameters were recorded at the end of storage. On a three-year average, fruit stored in CA was less ripe at the end of storage. After both four and six months storage, CA reduced total decay (physiological disorders and fungal decay) by on average 70% and 45%, respectively, compared to storage in ambient air. Senescent breakdown was lower after CA storage for four months, but not after six months and not after simulated shelf life. Soft scald was lower when stored in CA both after cold storage at 1°C and simulated shelf life. After storage at 3°C there was lower incidence of soft scald when stored in CA after four months, but not after six months. For fungal fruit decay in general, there was no effect of low oxygen, however, 2% O₂ gave slightly less bitter rot (Colletotrichum acutatum) than 1% O₂ and significantly less than ambient air after simulated shelf life. Averaged over all oxygen levels, 1°C gave significantly less bitter rot than 3°C. It may be concluded that use of CA for storage of ‘Aroma’ is a good way of reducing development of physiological disorders. However, development of bitter rot seemed to be more influenced by temperature and storage time than by low O₂.     

Effect of rate and source of nitrogen fertilizers on mineral composition of d'Anjou pears

Abstract

Thirteen‐year‐old ‘d'Anjou’ pear trees, Pyrus communis L., were fertilized with 3 rates of ammonium nitrate or 2 rates of calcium nitrate in late autumn from 1978 to 1980. In 1981, mid‐terminal and fruiting‐spur leaves and fruit peel and flesh were sampled for mineral analysis of N, P, K, Ca, Mg, B, Cu, Fe, Mn, and Zn. The level of N increased in the above tissues as rate of N fertilizer was increased. In most cases, the levels of N, P, K, Mg, Cu, and Mn in the fruiting spur leaves and fruit were greater in the ammonium nitrate‐treated trees than with calcium nitrate fertilizer. Calcium was higher in the fruit peel and flesh of trees treated with the low rate of calcium nitrate than with the highest rate of ammonium nitrate fertilizer while Ca in the fruiting spur leaves was lower in the calcium nitrate‐fertilized trees.     

Influence of root restriction on two cultivars of summer squash (Cucurbita pepo L.)

Variable root restricting conditions were imposed on summer squash (Cucurbita pepo L.) cultivars ‘Senator’ and Dixie’ using container sizes of 0.35, 2.00, and 7.60 liters. Nondestructive and destructive plant sampling were conducted to evaluate leaf area production, dry weight accumulation and partitioning, crop growth rate and net assimilation rate, and flower and fruit development. Within 10 days after transplanting (DAT), ‘Senator’ exhibited declining leaf area production under increased root restriction, and within 17 DAT leaf area was diminished for both cultivars under increased root restricting conditions. Dry weight accumulation in leaves, stems, roots, and fruit was reduced for both cultivars over time and level of root restriction severity. There was a tendency for greater vegetative growth reductions with ‘Senator’ than with ‘Dixie’ at comparable levels of root restriction. Root‐to‐shoot ratio, timing and duration of flowering, and sex of flowers were not significantly impacted by root restriction level or cultivar. Fruit dry weight was greatest for Dixie’ early on, but by 28 DAT, total fruit dry weight produced did not differ for the cultivars except under the most severe root restricting conditions. Fruit dry weight production was limited for both cultivars as container volume became smaller.     

The influence of phosphate fertilizer application levels and cultivars on cadmium uptake by Komatsuna (Brassica rapa L. var. perviridis)

Cadmium (Cd) is a common impurity in phosphate fertilizers and application of phosphate fertilizer may contribute to soil Cd accumulation. Changes in Cd burdens to agricultural soils and the potential for plant Cd accumulation resulting from fertilizer input were investigated in this study. A field experiment was conducted on Haplaquept to investigate the influence of calcium superphosphate on extractable and total soil Cd and on growth and Cd uptake of different Komatsuna (Brassica rapa L. var. perviridis) cultivars. Four cultivars of Komatsuna were grown on the soil and harvested after 60 days. The superphosphate application increased total soil Cd from 2.51 to 2.75?mg?kg^?1, 0.1?mol?L^?1 hydrochloric acid (HCl) extractable Cd from 1.48 to 1.55?mg?kg^?1, 0.01?mol?L^?1 HCl extractable Cd from 0.043 to 0.046?mg?kg^?1 and water extractable Cd from 0.0057 to 0.0077?mg?kg^?1. Cd input reached 5.68?g?ha^–1 at a rate of 240?kg?ha^–1 superphosphate fertilizer application. Superphosphate affected dry-matter yield of leaves to different degrees in each cultivar. ‘Nakamachi’ produced the highest yield in 2008 and ‘Hamami No. 2’ in 2009. Compared with the control (no phosphate fertilizer), application of superphosphate at a rate of 240?kg?ha^–1 increased the Cd concentration in dry leaves by 0.14?mg?kg^?1 in ‘Maruha’, 1.03?mg?kg^?1 in ‘Nakamachi’, 0.63?mg?kg^?1 in ‘SC8-007’ in 2008, and by 0.19?mg?kg^?1 in Maruha’, 0.17?mg?kg^?1 in ‘Hamami No. 2’, while it decreased by 0.27?mg?kg^?1 in ‘Nakamachi’ in 2009. Field experiments in two years demonstrated that applications of different levels of calcium superphosphate did not influence Cd concentration in soil and Komatsuna significantly. However, there was a significant difference in Cd concentration of fresh and dry Komatsuna leaves among four cultivars in 2008 and 2009. The highest Cd concentration was found in the ‘Nakamachi’ cultivar (2.14?mg?kg^?1 in 2008 and 1.91?mg?kg^?1 in 2009). The lowest Cd concentration was observed in the ‘Maruha’ cultivar (1.51?mg?kg^?1?dry weight (DW)) in 2008 and in the ‘Hamami No. 2’ cultivar (1.56?mg?kg^?1?DW) in 2009. A decreasing trend in Cd concentration was found in ‘Nakamachi’, followed by ‘SC8-007’, ‘Hamami No. 2’ and ‘Maruha’ successively. It is necessary to consider a low-uptake cultivar for growing in a Cd polluted soil. In these two years’ results, ‘Maruha’ cultivar was the lowest Cd uptake cultivar compared to the others.     

BORON NUTRITION OF PEANUT GROWN IN BORON-DEFICIENT CALCAREOUS SOILS: GENOTYPIC VARIATION AND PROPOSED DIAGNOSTIC CRITERIA

Field studies were conducted to assess boron (B) requirement, critical concentrations in diagnostic parts based on yield response curves and genotypic variation by growing three peanut (Arachis hypogaea L.) cultivars (‘Golden’, ‘BARD-479’, ‘BARI-2000’) on two B-deficient calcareous soils. Boron application significantly increased pod yield of all the cultivars over control. Maximum pod yield increases were: ‘Golden’, 16?23%; ‘BARD-479’, 21?27%; and ‘BARI-2000’, 25?31%. The cultivars varied in B efficiency and cv. ‘Golden’ was the most B efficient (81?86%) while cv. ‘BARI-2000’ was the least efficient (76?80%). Boron requirements for near-maximum (95%) dry pod yield were 0.65 kg ha^?1 for ‘Golden’, 0.75 kg ha^?1 for BARD-479 and 0.80 kg ha^?1 for BARI-2000. Critical B concentrations in shoots and seeds were: ‘Golden’, 33 mg kg^?1 and 26 mg kg^?1; ‘BARD-479’, 38 mg kg^?1 and 31 mg kg^?1; and ‘BARI-2000’, 42 mg kg^?1 and 33 mg kg^?1.     

Zinc Nutrition of Onion: Proposed Diagnostic Criteria

ABSTRACT

Zinc (Zn) deficiency is a global nutritional problem in crops grown in calcareous soils. However, plant analysis criteria, a good tool for interpreting crop Zn requirement, is scarcely reported in literature for onion (Allium cepa L.). In a greenhouse experiment, Zn requirement, critical concentrations in diagnostic parts and genotypic variation were assessed using four onion cultivars (‘Swat-1’, ‘Phulkara,’ ‘Sariab Red,’ and ‘Chilton-89’) grown in a Zn-deficient (AB-DTPA extractable, 0.44 Zn mg kg^?1), calcareous soil of Gujranwala series (Typic Hapludalf). Five rates of Zn, ranging from 0 to 16 mg Zn kg^?1 soil, were applied as zinc sulphate (ZnSO₄·7H₂O) along with adequate basal fertilization of nitrogen (N), phosphorus (P), potassium (K), and boron (B). Four onion seedlings were transplanted in each pot. Whole shoots of two plants and recently matured leaves of other two plants were sampled. Zinc application significantly increased dry bulb yield and maximum yield was produced with 8 mg Zn kg^?1. Application of higher rates did not improve yield further. The cultivars differed significantly in Zn efficiency and cv. ‘Swat-1’ was most Zn-efficient. Fertilizer requirement for near-maximum dry bulb yield was 2.5 mg Zn kg^?1. Plant tissue critical Zn concentrations were 30 mg kg^?1 in young whole shoots, 25 mg kg^?1 in matured leaves, 16 mg kg^?1 in tops and 14 mg Zn kg^?1 in bulb. Zinc content in mature bulb also appeared to be a good indicator of soil Zn availability status.     

Nutrient Dynamics: Effect on Cropping Behavior,Nutrient Profile and Quality Attributes of Pomegranate (Punica Granatum L.) Under Rainfed Agroclimatic Conditions

The study was carried out between 2008 and 2010 on 8-year-old pomegranate (Punica granatum L.) trees cultivar ‘Kandhari Kabuli.’ The potential efficiency of bio-organics used along with chemical fertilizers on cropping behavior, quality attributes, nutrient availability, physico-chemical, and biological properties of soil were investigated. Bioorganic nutrient sources, namely, vermicompost (VC), biofertilizers (BF), farm yard manure (FYM), and green manure (GM), along with chemical fertilizers was evaluated in 13 different treatment combinations. Conjoint treatment application of VC at 20 kg tree^?1, BF at 80 g tree^?1, FYM at 20 kg tree^?1, GM as sun hemp (Crotalaria juncea L.) along with 75% of the recommended dose of nitrogen–phosphorus–potassium (N–P–K) chemical fertilizers significantly resulted in maximum fruit set (52.03%) and fruit yield (34.02 kg tree^?1). All of the fruit quality characteristics were also improved significantly when compared to nitrogen–phosphorus–potassium (N–P–K) chemical fertilizers. This superior combination also enhanced physical-chemical and biological properties of the rhizosphere soil. Microbial biomass of in terms of Pseudomonas, total culturable soil fungi, Azotobacter chroococcum, actinobacteria, and arbuscular mycorrhizal (AM) fungi improved 385.57, 60.26, 134.19, 168.02, and 39.87%, respectively, over control. This combination also resulted in considerable greater concentration of leaf macro-and micronutrients: N (2.63%), P (0.25%), K (1.57%), iron (Fe; 197.87 mg kg^?1), copper (Cu; 14.65 mg kg^?1), zinc (Zn; 59.36 mg kg^?1), and manganese (Mn; 200.45 mg kg^?1).     

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.     

Effect of constant versus adjusted commercial fertilizer concentrations on poinsettia 1

Five poinsettia (Euphorbia pulcherrima Willd.), ‘Freedom Red’, ‘Angelika Red’, ‘Nutcracker Red’, ‘Maren’, and ‘Red Splendor’ received the following treatments of a commercial fertilizer based on nitrogen (N) concentrations of: 75 mg L^‐1 to anthesis; 75 mg L^‐1 first 4 weeks then 125 mg L^‐1 to anthesis; 125 mg L^‐1 first 4 weeks then 200 mg L^‐1 to anthesis; and 200 mg L^‐1 to anthesis. Plants were fertigated to appearance of leachate from the bottom of the pot. Treatment concentrations greater than 125/200 and 200 mg.L^‐1 significantly increased plant width of ‘Red Splendor’, height of ‘Nutcracker Red’ and dry weight of ‘Angelika Red’, ‘Nutcracker Red’, and ‘Maren’. Tissue concentrations of N, phosphorus (P), magnesium (Mg), and sulfur (S) increased as fertilizer treatment concentration increased for some cultivars. Significant differences between elemental concentrations of poinsettia cultivars occurred, specifically ‘Nutcracker Red’. Although tissue nutrient concentrations were at or below the critical level, general observations of each cultivar indicated that all plants were of commercial quality and almost indistinguishable between treatments. Poinsettia stem strength was not significantly affected by any fertilizer treatment used in this study.