Esmaeil Fallahi

Effect of Ammonium: Nitrate Ratio on Yield, Calcium Concentration, and Photosynthesis Rate in Strawberry

ABSTRACT The effect of ammonium:nitrate (NH4:NO3) ratio in nutrient solution on growth, photosynthesis (Pn), yield, and fruit quality attributes in hydroponically grown strawberry (Fragaria × ananassa Duch) cvs. ‘Camarosa’ and ‘Selva’ was evaluated. There were four nutrient solutions of differing NH4:NO3 ratios as follows: 0:100, 25:75, 50:50, and 75:25. Plants grown in solution with 75% NH4 had lower leaf fresh and dry weights and leaf area than those with 25% NH4 in both cultivars. High ratios of NH4 and NO3 in the solution always reduced the yield. The yield was increased by 38% and 84% in ‘Camarosa’ and ‘Selva,’ respectively, when the plants were grown in the 25NH4:75NO3 solution compared with plants grown in a higher NH4 ratio solution. The increased yield at the 25 NH4:75NO3 ratio was the result of the increase in fruit size, i.e., length and fresh weight of fruits. Plants grown in the 25NH4:75NO3 solution had the highest rate of Pn, while those grown in 75NH4:25NO3 solution had the lowest Pn rates in both cultivars. Increasing the NH4 ratio in the solution from 0 to 75% significantly reduced the calcium (Ca) concentration and postharvest life of the fruits in both cultivars. Both higher leaf area and Pn rate appeared to be the reason for the increased yield and plant growth in the 25:75 ratios of nitrogen (N). The results indicate the preference of strawberry plant growth toward a greater nitrate N form in a hydroponic solution. Therefore, a combination of two forms of N in an appropriate ratio (25NH4:75NO3) appears to be beneficial to plant growth, yield, and quality of strawberry fruits.

EFFECTS OF THREE ROOTSTOCKS ON PHOTOSYNTHESIS, LEAF MINERAL NUTRITION, AND VEGETATIVE GROWTH OF “BC-2 FUJI” APPLE TREES

Net photosynthesis (Pn), leaf nutrition, and current terminal shoot (CTS) growth of ‘BC-2 Fuji’ apple [Malus sylvestris (L.) Mill var.domestica (Borkh.) Mansf.] trees on three rootstocks, Budagovski (Bud.) 9, Ottawa 3, and M.7 EMLA under field conditions were studied in 1998 and 1999. Rootstock affected the scion leaf Pn, leaf mineral concentrations, and vegetative growth. Leaves of trees on Bud.9 had lower Pn than those on the other rootstocks, and the differences were significant in 1999. Scion leaves on Bud.9 had higher calcium (Ca) and manganese (Mn) but lower potassium (K) concentrations than those on the other rootstocks. Leaves of trees on M.7 EMLA had significantly higher magnesium (Mg), K, and copper (Cu) concentrations than those on the other rootstocks in both years. Trees on Ottawa 3 had significantly lower leaf Cu concentrations than those on the other rootstocks during both 1998 and 1999. Trees on Bud.9 rootstock had shorter limbs and terminal shoots than those on the other rootstocks in 1998 and 1999.

Effects of sodium chloride-induced salinity on mineral nutrients and soluble sugars in three commercial cultivars of pomegranate.

Abstract The effect of sodium chloride (NaCl)-induced salinity on concentration and translocation of ions and soluble sugars in three commercial cultivars, ‘Alak Torsh,’ ‘Malas Torsh,’ ‘Malas Shirin,’ of pomegranate (Punica granatum L.) was studied. After rooting of cuttings, they were planted in the plastic pots contained sand:perlite (1:1) medium and irrigated with complete Hoagland’s solution immediately. After three weeks, plants were treated with different concentration (0, 40, 80, and 120 mM) of NaCl solution. These treatments continued during 80 days with irrigation water. Finally, uptake and transport of ions [Na, potassium (K), calcium (Ca), magnesium (Mg), nitrogen (N), and Cl) and soluble sugars in these three cultivars were measured. With increasing NaCl concentration in irrigation water, the amount of Na, Cl, and K of the tissues increased, but amount of Ca, Mg, and N of the tissues decreased. No cultivar differences were observed in the rate of uptake of tested minerals. Soluble sugars decreased as NaCl concentrations in irrigation water increased.

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

Abstract Field experiments were conducted during 1994–1995 in seven apple (Malus spp.) orchards located in the southwest of Finland (the mainland and the Aland Islands). The cultivars were ‘Transparente Blanche’, ‘Samo’, ‘Melba’, ‘Raike’, ‘Red Atlas’, ‘Akero’, ‘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 wi...

Influence of Foliar and Ground Fertilization on Yield, Fruit Quality, and Soil, Leaf, and Fruit Mineral Nutrients in Apple

ABSTRACT The effectiveness of nitrogen (N)+ zinc (Zn) soil and foliar fertilizer applications on growth, yield, and quality of apple (Malus domestic Borkh ‘Golden Delicious’) fruit was studied in the Zanjan province, Iran. There were eight treatments 1) control (no fertilizer), 2) soil applied N, 3) soil applied Zn, 4) soil applied N+Zn, 5) foliar applied N, 6) foliar applied Zn, 7) foliar applied N+Zn and 8) combined soil and foliar applied N+Zn. The N source was urea [CO(NH2)2, 46% N] applied at 276 N tree− 1 yr−1 and the Zn source was zinc sulfate (ZnSO4,7H20, 23% Zn) applied at 110 g Zn tree− 1 yr− 1. The soil treatments of N and Zn, were applied every two weeks during June through August (total of 6 times/year) in a 1 m radius around the tree trunk (drip line of trees). The foliar solutions of N (10 g l− 1 urea) and Zn [8 g l− 1 zinc sulfate (ZnSO4)] were sprayed at the rate of 10 L tree− 1 every two weeks at the same times as described for soil applications. The highest yield (49 kg tree− 1), and the heaviest fruits (202 g) were obtained in the soil and foliar combination of N+Zn treatment. The lowest yield (35 kg tree− 1), and the smallest fruits (175 g) were recorded in the control. Nitrogen, and to a lesser extent Zn, foliar application resulted in decreasing fruit quality (caused russeting, and lower soluble solid), but increasing N leaf and fruit concentrations (2.4% DW and 563 mg kg− 1, respectively). There were significant differences among yield and leaf mineral nutrient concentration in different treatments. But there was no significant difference between fruit mineral nutrient concentration (except N). Ratio of N/calcium (Ca), potassium (K)/Ca, and [magnesium (Mg)+K]/Ca in fruits were found suitable for fruit quality prediction. Combining the zinc sulfate with urea in the foliar applications increased the concentration of Zn from 0.7 to 1.5 mg per kg of apple tissue. Leaf N concentration varied during growth season. Foliar applied nutrient can be more efficient than soil applied, but a combination of soil and foliar applications is recommended for apple tree nutrient management.

Partitioning of Chlorine, Sodium, and Potassium and Shoot Growth of Three Pomegranate Cultivars Under Different Levels of Salinity

ABSTRACT Salinity is a major problem in a wide pomegranate-growing area of central Iran. Effects of four levels of salinity on leaf and root chlorine (Cl), sodium (Na), and potassium (K) partitioning and shoot growth in three major commercial cultivars of pomegranate (Punica granatum), namely ‘Alak Torsh,’ ‘Malas Torsh,’ and ‘Malas Shirin,’ under climatic conditions of central Iran were investigated. Pomegranate cuttings were rooted and planted in plastic pots containing 1:1 sand:perlite medium and irrigated immediately with complete Hoaglands solution immediately. Four salinity levels of irrigation water (0, 40, 80, and 120 mM NaCl) were used. Final concentrations of NaCl were achieved after three weeks and continued for 80 d. Growth characteristics (i.e., length of the main stem, length and number of internodes, and leaf surface) were measured during the experiment. At harvest, concentrations of Na, K, and Cl in root and apical and basal leaves of the three cultivars were determined separately. In ‘Malas Torsh’ and ‘Alak Torsh’ cultivars, increasing salinity was proportional to NaCl concentration and reduced the length of stem, the length and number of the internodes, and leaf surface. There was an increase in the growth rate of the ‘Malas Shirin’ cultivar with increasing salinity up to 40 mM, but a decline in growth rate occurred at salinity levels higher than 40 mM. With increasing salinity level, the tissue concentration of Na and Cl increased while the K/Na ratio decreased. No significant differences were observed among the three cultivars in Na, Cl, and K concentrations of roots or apical or basal leaves. These results show that ‘Malas Shirin’ grew better under saline conditions compared with the ‘Malas Torsh’ and ‘Alak Torsh’ cultivars.

Nitrogen and calcium nutrition and fruit quality of commercial apple cultivars grown in Finland

Abstract During 1994–1995, field experiments were conducted in six apple orchards located in the southwest of Finland (the mainland and the Aland Islands). The cultivars were ‘Melba’, ‘Raike’, ‘Red Atlas’, ‘Lobo’, ‘Aroma’, and ‘Akero’. Fruit samples were picked at about one week before commercial maturity and stored for three to six months at 2 to 4°C and 85–95% relative humidity. During storage the percentage of physiological disorders was visually recorded. Fruit nitrogen (N) and calcium (Ca), firmness, diameter, juice titratable acidity (TA), and soluble solids concentrations (SSC) were determined at harvest. Nitrogen and Ca in the soil and leaves collected during fruit development were determined. The ranges in fruit N were 296–624 and Ca 27–68 mg kg‐1 fresh weight, and in the leaves N 15–23 and Ca 9–19 g kg‐1 dry matter. The N/Ca ratio was 5 and 16 and 0.9 and 2.3 in fruit and leaves, respectively. There was more variation between years in N and Ca contents of leaves than that of fruit. Other fruit q...

Influence of apple rootstocks and k and n fertilizers on leaf mineral composition and yield in a high density orchard

Abstract Leaf mineral composition of ‘Starkspur Golden Delicious’ apple (Malus domestica Borkh.) on six rootstocks: Seedling, M 1, M 7, M 26, MM 106, and OAR 1 was monitored in a high density orchard. Two levels of K and N fertilizers were applied as soil treatments for the two‐year study. N, P, and K concentrations decreased while Mg and Ca increased in scion leaves on all rootstocks during the 1981 growing season. A higher demand for K and P was observed in fruit tissue as cropping increased in some rootstocks, leading to lower leaf concentrations of these elements. Scion leaves on OAR 1 had significantly lower Ca than on M 7, MM 106 and M 1 and lower Mg than on M 26. Those on MM 106 had the highest levels of Ca in both years. Scion leaves on OAR 1 had higher B than other rootstocks. Scion leaves on M 26 had significantly higher Mg than those on M 1, MM 106 and OAR 1. Leaves on M 7 had at least 8% more Cu than other rootstocks. Soil applications of K significantly decreased Ca and Mg concentrations whil...

Interactive Effects of Potassium and Calcium on K/Ca Ratio and Its Consequences on Apple Fruit Quality in Calcareous Soils of Iran

Abstract This research was carried out during the 2000–2001 growing season in a low-density orchard, on a calcareous soil (Fine loamy, mixed, mesic Typic Calcixerept) in northwest Iran, using 25-year old “Golden Delicious” (Malus domestica Borkh.) apple trees on M.9 rootstock. The interactive effects of potassium (K) and calcium (Ca) on K/Ca ratio and its consequences on apple fruit quality were studied. Treatments included: T 1 = control [nitrogen (N), phosphorus (P), and manure]; T 2 = T 1 + micronutrients (deep placement) based on soil test recommendations; T 3 = T 2 + (KCl)1 based on soil test recommendations; T 4 = T 3 + spray of CaCl2 at four times; T 5 = same as T 4 but sprayed at eight times; T 6 = T 2 + (KCl)2 (50% above soil test); T 7 = T 6 + spray of CaCl2 at four times; T 8 = same as T 7 but sprayed at eight times; T 9 = same as T 8 but with an equal amount of K from K2SO4 source. Leaf samples were collected in early July and fruit samples collected in early October and were analyzed for N, K, and Ca. Thirty fruit samples were randomly selected and stored at 1°C for 45 or 90 days prior to determination of their storage life. There was a range in K and Ca level in the leaves, although both K and Ca concentrations exceeded their critical threshold values. The concentration of K in the fruit was high, but Ca was low. There was a positive correlation between leaf K and fruit K and between fruit K and total soluble solids concentration (SSC); between fruit Ca and apple fruit firmness; but negative correlations existed between K/Ca ratio and apple fruit firmness at harvest. Apple fruit SSC was increased by K-fertilization and storage period. Fruit firmness in harvest samples was the highest in plots which had received Ca sprays. Apple firmness at harvest was generally low for all treatments and reduced by duration of storage and differences among treatments were not large after 90-day storage. Variation of K/Ca ratio in the apple leaves was slight (0.9–1.4), but a wide range was observed for fruit (19–46). The highest ratio (46) occurred for T 6 and the lowest ratio (19) for T 8 and T 9. An inverse relationship between K/Ca ratios and fruit firmness indicated that on calcareous soils, at least 8-foliar applications of CaCl2 solution were necessary for “Golden Delicious” apple. #Contribution no. 2191, PARC-Summerland.

Relationships among mineral nutrition, ethylene and post-harvest physiology in apples on six rootstocks

Abstract The relationships among several mineral elements of August-sampled leaf October-harvested fruit, maturity and post-harvest quality factors of ‘Starkspur Golden Delicious’ apple trees grown on Seedling, Malling (M) 1, Malling Merton (MM) 106, M 7, Oregon Apple Rootstock (OAR 1) or M 26 in a high-density orchard during 1980–1982 were evaluated. Positive correlations were found between leaf N, K and P and fruit N, K and P, respectively, in most rootstocks. Leaf Ca did not correlate with fruit Ca; thus leaf analysis cannot be recommended for estimates of fruit Ca. Both leaf and fruit N positively correlated with fruit green color and negatively with fruit soluble solids in all rootstocks. Fruit Ca and fruit P were both negatively correlated with fruit soluble solids at harvest and after 6 months of 0°C storage for all rootstocks. The ratio of fruit N Ca was positively correlated with internal ethylene in MM 106, M 7 and OAR 1, while fruit K Ca ratio was positively correlated with titratable acidity in all rootstocks. Fruit Ca showed negative correlations with bitterpit, storage rot and field internal ethylene, but positive correlation with firmness. Yield was positively correlated with leaf and fruit N, Ca and Cu but slightly negatively correlated with B of those tissues. Higher yield was associated with lower leaf K concentrations. Fruit green color was negatively correlated with soluble solids and titratable acidity. Fruit dry matter was highly positively correlated with soluble solids and titratable acidity in MM 106, OAR 1 and M 26. Soluble solids at harvest were strongly predicted by pre-harvest dry matter.