INFLUENCE OF PREHARVEST SPRAYS OF A MIXTURE OF CALCIUM FORMATE,CALCIUM ACETATE,CALCIUM CHLORIDE AND CALCIUM NITRATE ON QUALITY AND ‘JONAGOLD’ APPLE STORABILITY

The aim of the study was to examine effect of preharvest sprays of a mixture of calcium (Ca) formate, Ca-acetate, Ca-chloride (CaCl₂) and Ca-nitrate [Ca(NO₃)₂] on quality and apple storability. The experiment was conducted during 2008–2009 at the Experimental Station of the Research Institute of Horticulture in Skierniewice, Poland, on mature ‘Jonagold’ apple trees/M.26, planted at a moderate density on a coarse-textured soil with low status of organic matter and abundant in exchangeable Ca. Apple trees were sprayed with Ca, 7 times per season, at 2-week intervals, starting 3 weeks after blooming. In the spray treatments a mixture of Ca-formate, Ca-acetate, CaCl₂ and Ca(NO₃)₂ (as Insol Wap fertilizer), CaCl₂ or Ca(NO₃)₂ were used at rates of 7.3 kg Ca, 11.8 kg Ca, and 9.9 kg Ca ha^?1 per season, respectively. The trees sprayed with water were treated as the control. The results showed that Ca sprays caused no leaf and fruit injury. Calcium spray measures did not affect yield, mean fruit weight, and soluble solids concentration (SSC), titratable acidity and starch index of fruit at harvest. However, at harvest apples sprayed with Ca contained more this nutrient and were firmer than those of the control plots. After storage apples sprayed with Ca had more acids, and were firmer and less liable to bitter pit than the control fruit. Calcium sprays did not affect SSC of fruit after storage but reduced postharvest decay of fruit caused by Peziculla spp. and Penicillium expansum fungi. Apples sprayed with Insol Wap material were the least affected by the above pathogens. It is concluded that in apple orchards preharvest sprays of a mixture of Ca-formate, Ca-acetate, CaCl₂ and Ca(NO₃)₂, containing 10% Ca (w/w) with ca. 50% in an organic form, can be the alternative to sprays of CaCl₂ or Ca(NO₃)₂.     

RESPONSE OF ‘BURLAT’ SWEET CHERRY TREES TO POSTHARVEST SPRAYS OF NITROGEN,BORON AND ZINC

The aim of the study was to examine effects of postharvest sprays of nitrogen (N), boron (B), and zinc (Zn) on reproductive response of sweet cherry (Prunus avium L.) trees, fruit quality and plant nutrition. The experiment was conducted during 2007–2009 in central Poland on mature ‘Burlat’ sweet cherry trees/F12, grown on a coarse-textured soil with low level of organic matter, and optimal soil reaction. Soil status of phosphorus (P), potassium (K), magnesium (Mg), calcium (Ca), iron (Fe), manganese (Mn), Zn and copper (Cu) was optimal, whereas B – low. Sweet cherry trees were sprayed with boric acid-B, ethylenediaminetetraacetic acid (EDTA)-Zn, and urea-N at 30–40 d prior to initiation of leaf fall according to following schema: i) spray of N at a rate of 23 kg ha^?1; ii) spray of B and Zn at a dose of 1.1 kg ha^?1 and 0.5 kg ha^?1, respectively; and iii) spray of N, B and Zn at the same rates as in the above spray combinations. The trees sprayed with water served as the control. The results showed that fall spray treatments had no influence on cold damage of flower buds, plant N status and soluble solids concentration in fruit. Postharvest spray of N and combined spray of N, B and Zn injured leaves in the fall but did not cause defoliation. Sprays of B and Zn with or without N increased status of Zn and B in fall leaves, and B in flowers and midsummer leaves. Those sprays also improved fruit set and yield. In one out of two years of the study, fall sprays of N with or without B and Zn decreased mean fruit weight. The above results indicate that only leaf-applied B in the fall improved reproductive response of sweet cherry trees. It is concluded that under conditions of B shortage in a soil and/or plant tissues, postharvest B sprays can be recommended in sweet cherry orchards to improve reproductive growth of the trees.     

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.     

FOLIAR APPLICATION OF ZINC INFLUENCES THE LEAF MINERAL STATUS,VEGETATIVE AND REPRODUCTIVE GROWTH,YIELD AND FRUIT QUALITY OF ‘KINNOW’ MANDARIN

Deficiency of zinc (Zn) is widespread in many citrus orchards of Pakistan, consequently hampering fruit yield. Effects of foliar applications of zinc sulfate on tree nutrition, growth, productivity and fruit quality were studied on ‘Kinnow’ mandarin. Leaf nitrogen (N), calcium (Ca), and manganese (Mn) were highest for trees sprayed with 0.2% zinc sulfate, while phosphorus (P) and iron (Fe) were highest with 0.6% zinc sulfate and potassium (K) and Zn were highest with 0.8% Zn sulfate applications. Trees sprayed with 0.6% zinc sulfate exhibited highest increase in height, crown width and stem girth, fruit diameter, fruit weight, ascorbic acid contents, and total phenolics compared to all other treatments. Pre-harvest fruit drop was lowest and total number and weight of fruit per tree was highest at harvest with 0.4% zinc sulfate application. In conclusion, foliar application of zinc sulfate up to 0.6% improved tree mineral nutrients, growth, and productivity with better fruit quality in ‘Kinnow’ mandarin.     

EFFECTS OF BAG-CONTROLLED RELEASE FERTILIZER ON NITROGEN UTILIZATION RATE,GROWTH AND FRUITING OF THE ‘FUJI’ APPLE

Bag-controlled release fertilizer is a new type of controlled-release fertilizer designed to meet the needs of the large individual volume characteristic of fruit trees. The effect of bag-controlled release fertilizer on nitrogen (N) utilization, growth-rate, and fruiting was investigated using ‘Fuji’ apple trees (M. domestica Borkh. cv. ‘Fuji’/M.hupehensis Rhed.). The results showed that the available concentration of nutrients in the soil following bag-controlled release fertilizer treatment (BCRT) was more consistent than when application treatments were broadcasted. The BCRT significantly increased N use efficiency, where this was 2.7 or 1.6 times greater than one or four broadcasted treatments, respectively. Trees treated via BCRT were healthier and had more quality spurs due to more constant nutrient concentration in the soil. With the same application amount, the chlorophyll level and Pn content of BCR-treated trees were steadier and higher than those of broadcasted controls; thus, BCRT significantly increased both yield and fruit quality.     

FOLIAR APPLICATION OF BORON INFLUENCES THE LEAF MINERAL STATUS,VEGETATIVE AND REPRODUCTIVE GROWTH,YIELD AND FRUIT QUALITY OF ‘KINNOW’ MANDARIN (CITRUS RETICULATA BLANCO.)

The effects of foliar application of boron (B) in the form of boric acid on vegetative and reproductive growth, yield and fruit quality of ‘Kinnow’ mandarin (Citrus reticulate Blanco.) were investigated. Kinnow mandarin was sprayed with different concentrations of boric acid viz. (0.1%, 0.2%, 0.3% and 0.4%) at fruit set stage. Leaf nitrogen (N), phosphorus (P), potassium (K), B, and zinc (Zn) along with flush length, tree height, tree spread and tree trunk diameter increased, while leaf length and leaf age showed non-significant results after foliar B application. Yield of the ‘Kinnow’ mandarin was significantly affected by foliar application of B and a significant increase in fruit weight at harvest was also observed. Soluble solid concentration (SSC): titratable acidity (TA) ratio, ascorbic acid, total sugars, total phenolic content (TPC) and total antioxidants significantly affected, while pH of juice, SSC, TA, reducing sugars and non-reducing sugars showed non- significant results.     

EFFECTS OF MIXING RATIO AND PROCESSING METHODS ON RESISTANT STARCH CONTENT OF PRODUCTS OF RICE＇ JIANGTANGDAO 1＇

以高抗性淀粉含量功能性粳稻品系“降糖稻1号”稻米为主要材料,研究其与不同比例稻米混配后经蒸煮、膨化、制作米粉及发酵加工后,对稻米产品直链淀粉含量和抗性淀粉（RS）含量的影响。结果表明,稻米中RS含量随加工温度和加工压力的提高而大大降低,表明“降糖稻1号”不宜高温高压蒸煮、膨化、加工米粉和发酵食品。“降糖稻l号”与“金丰”稻米按不同比例混合蒸煮后,其直链淀粉含量、RS含量及蒸煮品质有明显改善,“降糖稻1号”与“金丰”稻米以2：1混配,不仅明显改善米饭的食味,而且RS含量能保持较高的水平。     

EFFECT OF PREHARVEST SPRAYS OF CALCIUM CHLORIDE AND SUCROSE ON CRACKING AND QUALITY OF ‘BURLAT’ SWEET CHERRY FRUIT

The aim of the study was to examine impact of preharvest sprays of calcium (Ca) and sucrose on splitting and quality of ‘Burlat’ sweet cherry fruit. The study was carried out during 2009–2010 in Poland and Turkey, on mature trees planted at a moderate density on coarse- and medium-textured soils. Sweet cherries were sprayed with calcium chloride (CaCl₂) and/or sucrose at a rate of 5 kg of each material per ha, using ca. 1000 L of water. In Poland, sprays of CaCl₂ and/or sucrose were applied 8–14 h before each rain, starting 21 d before harvest, whereas in Turkey the spray treatments were made schematically: 7, 14 and 21 d before harvest. Sprays of water were treated as the control. The results showed that preharvest sprays of CaCl₂ and/or sucrose did not affect yield, mean fruit weight, and fruit acidity. Sprays of CaCl₂ increased fruit Ca status, and simultaneously reduced fruit cracking in an orchard or laboratory test. In the trial performed in Turkey, part of fruit sprayed with CaCl₂ (<5%) had spray deposit on the peel. Sucrose sprays did not affect fruit cracking. In one year of the study in Turkey, sucrose sprays increased soluble solids concentration of fruit; however, part of fruit treated with sucrose (<2%) had spray deposit on the skin.     

EFFECTS OF SINGLE,DUAL AND TRIPLE INOCULATIONS WITH BACILLUS SUBTILIS,BACILLUS MEGATERIUM AND RHIZOBIUM LEGUMINOSARUM BV. PHASEOLI ON NODULATION,NUTRIENT UPTAKE,YIELD AND YIELD PARAMETERS OF COMMON BEAN (PHASEOLUS VULGARIS L. CV. ‘ELKOCA-05’)

This study was conducted in order to investigate the effects of single, dual, and triple inoculations with Rhizobium, N₂-fixing Bacillus subtilis (OSU-142), and P-solubilizing Bacillus megaterium (M-3) on nodulation, plant growth, nutrient uptake and seed yield of common bean (Phaseolus vulgaris L. cv. ‘Elkoca-05’) in comparison to control and mineral fertilizer application under field conditions in 2006 and 2007 in the cold highland in Erzurum plateau (29° 55′ N and 41° 16′ E with an altitude of 1850 m), Turkey. Bacterial inoculations significantly increased all the parameters investigated compared with the control treatment, equal to or higher than nitrogen (N), phosphorus (P), and NP treatments. The lowest shoot dry weight and chlorophyll content values were recorded in the control treatment and the bacterial inoculations increased shoot dry weight by 19.7–54.3% and chlorophyll content by 34.1–59.3% over control. Nodule dry weight significantly increased in Rhizobium alone treatment. Additionally, nodulation by native soil Rhizobium population was increased in single inoculations of OSU-142 and M-3. Significant increases of the seed yield under different inoculation treatments ranged between by 6.6% (Rhizobium + OSU-142 + M-3) and 12.2% (OSU-142 alone) over the control whereas N, P and NP applications corresponded to increases of 5.6%, 4.0% and 7.4%, respectively. All bacterial inoculations, especially triple inoculation, significantly increased uptake of macronutrients and micronutrients by common bean. In conclusion, seed inoculation with Rhizobium, OSU-142 and M-3, especially OSU-142 alone, may substitute partially costly NP fertilizers in common bean production even in cold highland areas such as in Erzurum.     

EFFECTS OF POTASSIUM NITRATE SPRAYING ON FRUIT CHARACTERISTICS OF ‘MALAS YAZDI’ POMEGRANATE

The present research was carried out to investigate the effects of potassium nitrate on pomegranate fruit quality. Treatments were: 1) control, distilled water was used; 2) potassium nitrate 250 mg L-¹ plus Tween-20 and 3) potassium nitrate 500 mg L-¹ plus Tween-20. All treatments were sprayed on fruits with a diameter of 30 mm. Juice, peel, seed characters, and fruit quality components were evaluated when fruits were harvested. Results indicated that 250 mg L-¹ potassium treatment increased juice volume and weight compared with the control and the 500 mg L-¹ K treatments. As the potassium nitrate level increased, aril length and diameter decreased. Although there was not a significant difference among treatments on titrable acidity and pH contents of fruits, the highest total soluble solids and vitamin C were obtained in the 250 mg L-¹ potassium nitrate treatment when compared with the others. These findings show that applied potassium nitrate significantly influences fruit quality of pomegranate when fruit are in the beginning stages of growth and development.     

NITROGEN–PHOSPHORUS–POTASSIUM EFFECTS ON FORMS OF SULFUR IN LEAVES AND FRUITS OF CUCUMBER

ABSTRACT

The impact that nitrogen (N), phosphorus (P), and potassium (K) application rates on the sulfur (S) fractions in leaves and fruits of greenhouse-grown cucumbers plants (Cucumis sativus L. cv. Brunex) are presented. The treatments were as follows: N (N1=5 g NO₃NH₄/m², N2=10 g NO₃NH₄/m², N3=20 g NO₃NH₄/m², N4=40 g NO₃NH₄/m²), two levels of P (P1=8 g H₃PO₄/m² and P2=16 g H₃PO₄/m²), and two levels of K (K1=20 g K₂SO₄/m² and K2=40 g K₂SO₄/m²). The foliar and fruit contents were determined for total S, organic S and sulfate. The influence of the N treatments on the total S (St: organic S +sulfate) concentration, proved significant, showing a progressive increase in the leaf and fruit concentrations. In the leaves, the P slightly diminished the St concentration but values in the fruits did not appreciably differ from control. The K dosage did not cause the St concentration to differ from that of P, although in the fruit a slightly lower St concentration appeared in the K2 treatment. The response of the organic-S concentration in the leaves resembled that of St, and thus organic S should not be used as a diagnostic method for S status. In the relationship SO₄ ^2-/St, the SO₄ ^2- concentration proved more influential than did the St form, providing a more accurate representation of the potential status of this nutrient in the plant.     

ARE ORGANIC N FERTILIZING STRATEGIES ABLE TO IMPROVE LETTUCE YIELD,USE OF NITROGEN AND N STATUS?

Despite the importance of fertilizing practices in the crop yield improvement, nitrogen (N) utilization, and N status, their management by farmers is still rather empirical, especially when new organic materials are applied. Therefore, the aim of this research was to study the possible bio-products (anaerobic digestates and on-farm compost) applications and to evaluate their effects on lettuce performance, N efficiency and soil properties. The plant and soil N indicators were also investigated to reduce the N supply in lettuce production. To accomplish these objectives a three-year field experiment was carried out comparing the following N fertilization strategies: organic, with anaerobic digestates, based on stabilized wine distillery wastewater (SAD) and not stabilized wine distillery wastewater (NSAD) and on-farm compost, based on olive pomace compost (OPC); mineral (MIN), with ammonium sulfate and ammonium nitrate; mineral-organic, with a slow N release commercial fertilizer (CORG). All treatments received 140 kg N ha^?1 and they were compared with an unfertilized control (CONTR). The organic material application increased the marketable yield of 25.6, 20.3 and 10.1% for SAD, NSAD, and OPC treatments, respectively, in comparison with the CONTR. No significant reduction was found for both anaerobic digestates in respect to conventional fertilizers, while the OPC application significantly decreased the crop yield compared to MIN and CORG treatments. Moreover, the marketable head weight showed no significant difference among MIN, CORG, and SAD treatments, while a significant reduction of the weight was observed for NSAD and OPC. These findings highlighted the importance of organic fertilizer choice to sustain lettuce yield. The anaerobic digestates also enhanced head weight of 18.9 and 11.9% for SAD and NSAD, respectively, compared to CONTR, pointing out that the by-products application could be a valid agricultural practice to provide nutrients. Besides, no significant difference in N utilization parameters was found between SAD, MIN and CORG, indicating the effectiveness of the stabilized wine wastewater. Among the plant and soil N indicators tested, our results suggested that the leaves green index and nitrate contents in the leafstalks not only were the most reliable methods for evaluating N status, but they also offered potential advantages of both an easier sampling and a higher positive correlation with lettuce performance. Finally, since the agro-industrial residues did not significantly increase the soil potentially toxic elements level, the findings of this research pointed out that the organic materials can be usefully applied, at least in the short-term period.     

EFFECTS OF ELEMENTAL SULFUR AND MYCORRHIZAE ON THE YIELD OF WHEAT IN DIFFERENT SOILS

Yield responses of wheat (Triticum aestivum L.) to elemental sulfur (S), mycorrhizae (mycorrhizal fungus, Glomus mosseae), and phosphorus (P) alone and collectively in two different soils were investigated. Plants were grown on calcareous sterilized Karaburun and Menek?e soils (sub-group of Typic Xerorthent). In the all treatments mycorrhizae inoculation alone compared to the control treatment increased shoot and root yields. The yield responses to S alone, P alone, and combined application of S and P in mycorrhizal and non-mycorrhizal treatments in two different soils were interestingly fluctuating. The findings obtained in this study indicated that S tended to increase the efficiency of mycorrhizae in the well aerated Karaburun soil in comparison to a less aerated (heavier textured) Menek?e soil. This potential to increase the efficiency of mycorrhizae on the root growth indicate that yield increase of shoot and grain can occur being an important finding for ecological agriculture.     

CORRELATION BETWEEN YIELD,MUST ATTRIBUTES AND NUTRITIONAL STATUS OF THE GREEK RED WINE GRAPE VARIETY ‘AGIORGITIKO’

The appropriate tissue and sampling time for the Greek wine-grape variety ‘Agiorgitiko’ nutritional diagnosis was to be evaluated by relating leaf tissue nutrient contents with the yield and must potassium (K), pH, total soluble solids (TSS), and titratable acidity (TA). At bloom, véraison and harvest, leaves opposite the basal cluster (LOBC) and youngest mature leaves (YML) were harvested, and soil and berry samples were collected from six vineyards in Nemea, Greece. Petiole K concentration of the LOBC was found to be better correlated with the yield, TSS, TA and must K than the blade or whole leaf K content; the contrary was observed in nitrogen (N), phosphorus (P), calcium (Ca), and magnesium (Mg) concentrations. The LOBC reflected better the nutritional status of the variety compared to the YML. Regarding the sampling time, petiole K presented stronger correlations with yield and must K, TSS, TA at harvest whereas N and P at bloom and véraison.     

BIOREGULATORS INFLUENCE CALCIUM CONCENTRATION AND COLD HARDINESS OF YOUNG ‘DELICIOUS’ (MALUS DOMESTICA,BORKH) APPLE TREES

Calcium concentration and cold hardiness in woody shoots of young ‘Delicious’ apple trees increased during the first half of the dormant season by early-fall whole-tree application of bioregulators and/or plant protectant. Compared with untreated controls, the plant protectant, α-[(1,3-dioxolan-2-ylmethoxy) imino] benzene acetonitcile [Hytech Polymer, (formerly ProTec^TM), Agro-K, Corp., Minneapolis, MN, USA] applied in September at 5 or 10% induced more cold hardiness in late October and November, whereas treating at 0.05% with the bioregulator, 2-chloroethyl-methyl-bis(phenylmethoxy)silane [CGA-15281, Novartis International AG, (formerly Ciba-Geigy Limited) Basel, Switzerland], induced greater cold hardiness and higher woody tissue calcium concentration in November and December. Applied in October, CGA-15281 resulted in woody tissue with the highest cold hardiness rating from November through March. From October 28 through 8 December, tissue from control trees had the lowest calcium concentration and frequently the least amount of cold hardiness. In woody stems of young apple trees, cold hardiness was more closely related to calcium concentration than that of the other eleven measured mineral elements; this was especially apparent from November to March (r = ?0.856).     

VEGETATIVE GROWTH,YIELD, FRUIT QUALITY AND FRUIT AND LEAF COMPOSITION OF STRAWBERRY CV. ‘PAJARO’ AS INFLUENCED BY SALICYLIC ACID AND NICKEL SPRAYS

Salicylic acid (SA) occurs naturally in plants at low concentrations. Previous studies reported a vast range of responses after SA application on plants. Nickel (Ni) as an essential element for plant growth and development has been proven to have positive impact on overall plant life cycle. To evaluate influence of these two compounds on strawberry plants cv. ‘Pajero’ this study was carried out as a 3 × 4 factorial in a completely randomized design in greenhouse conditions. Treatments included SA at 0, 1, 2, and 3 mM and nickel sulfate (NiSO₄) at 0, 150 and 300 mg L^?1 concentration. It seems that treatments had promoting effects on measured parameters as 2 mM of SA increased root and shoot fresh and dry weight, concentration of anthocyanins and poliphenolics of fruits significantly, 3 mM of this phytohormone caused augmentation of vitamin C content of fruits. Nitrogen and nickel concentration within leaves and fruits were affected after SA treatments. 150 mg L^?1 of nickel solution promoted total yield, root dry weight and nitrogen concentration of fruits. Worth mentioning, beneficial effects of such treatments were higher when applied together. Further research is needed before recommendation on other cultivars and commercial use.     

LEAF MINERAL COMPOSITION OF ‘NOVA’, ‘ROBINSON’ AND ‘FREMONT’ MANDARIN CULTIVARS ON DIFFERENT ROOTSTOCKS

Rootstock selection has a critical importance for mineral nutrition of budded cultivars. This study was conducted at the experimental farm of Mustafa Kemal University, Dörtyol, Turkey. The aim of this study was to investigate the effect of sour orange, Troyer and Carrizo citrange rootstocks on the leaf nutrient contents of ‘Nova’, ‘Robinson’, and ‘Fremont’ mandarin cultivars in the 2004 and 2005 growing seasons. Carrizo citrange was examined for nitrogen (N), potassium (K), magnesium (Mg), sodium (Na), and manganese (Mn); Troyer citrange for iron (Fe); and sour orange for calcium (Ca) and zinc (Zn) were superior on the others. Nitrogen, phosphorus (P) and Mg levels of mandarin leaf budded on sour orange were under or just above the deficiency threshold. Potassium, Mn, and Zn content of ‘Robinson’; P, Ca and Fe content of ‘Fremont’; and Cu content of ‘Nova’ were statistically higher. Therefore, it can be concluded that Carrizo rootstock may be suggested for the region and regions with similar ecological conditions.     

EFFECTS OF FOLIAR AND SOIL CALCIUM APPLICATION ON YIELD AND QUALITY OF TABLE GRAPE CV. ‘THOMPSON SEEDLESS’

Table grape quality and firmness are key parameters for Chile's export, given distances from the main markets. As a consequence, calcium (Ca) fertilization has become a standard practice in the country, although its effects have not been fully evaluated. The objectives in this study were to investigate the effects of calcium fertilization on table grape nutrition and quality. A two-year field trial was conducted in central Chile, using grapevines (Vitis vinifera) cv. ‘Thompson seedless’, grown on an overhead trellis system. Calcium (CaCl₂) application treatments included foliar, soil, foliar plus soil, and a control without Ca fertilization. Calcium and other nutrients concentration were determined afterwards in soil, leaves, and berries. Also, yield and some fruit quality parameters were evaluated. Calcium application method did not have an effect on soil, leaf or fruit Ca content, neither on yield and berry sugar concentration, with levels being similar to the control treatment. Additionally, in treatments where CaCl₂ was applied to soil, chlorides concentration in soil, leaves, and berries were higher. Also, berries were larger, more turgent, with lower dry matter and larger cells. In the second season, in these same treatments, berry firmness at harvest was higher, but this effect disappeared after the storage simulation period. These results question the validity that Ca applications might improve table grape postharvest quality for growing conditions similar to the ones in this experiment. The temporal changes in berry quality parameters were attributed to higher Cl soil content and the associated plant osmoregulatory mechanisms.     

INFLUENCE OF ROOTSTOCK ON MINERAL UPTAKE AND SCION GROWTH OF ‘GOLDEN DELICIOUS’ AND ‘ROYAL GALA’ APPLES

Influence of four rootstocks (M.9, MM.106, MM.111, and local seedling) on the scion leaf and fruit mineral concentrations, tree growth, yield and fruit quality attributes of ‘Golden Delicious’ and ‘Royal Gala’ apples during four seasons (2008–2011) were significant. The mechanisms behind the influence of rootstock on scion vigor and yield was that the rootstock brought about its effects upon the scion by influencing the amounts of minerals taken up and translocated to the scion. ‘Royal Gala’ and ‘Golden Delicious’ trees on seedling had the highest efficiency in calcium (Ca) and potassium (K) uptake. Whereas, trees of these cultivars on M.9 were more efficient in nitrogen (N), manganese (Mn) and iron (Fe) uptake. MM.106 had the highest efficiency in phosphorous (P) uptake, and M.9 had the lowest K and Ca uptake. The highest N- fruit concentration and the lowest Ca-fruit concentration were observed in cultivars on M.9.