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.     

Effect of soil water management and different sowing dates on maize yield and water use efficiency under drip irrigation system

A 2-year field experiment (2012–2013) was conducted to evaluate the yield and water use efficiency (WUE) response of maize (Zea mays L.) to different soil water managements at different sowing dates. The experiment included three sowing dates (22 June, 6 July and 21 July) and four irrigation regimes based on maximum allowable depletion (MAD) of the total available soil water (TAW). The irrigation treatments were marked by I₁ to I₃ as 40%, 60% and 80% MAD of TAW, respectively, and with no irrigation. The results showed that grain yield reduced when planting was delayed in both years, ranging from 6105 to 4577 kg ha^?1 in 2012 and from 7079 to 5380 kg ha^?1 in 2013. However, WUE increased when planting was delayed from 22 June until 21 July. Also the highest grain yield was observed in the first irrigation treatment (MAD = 40%) in both years, and the highest WUE was obtained in the second irrigation treatment (MAD = 60%) with 1.64 and 1.61 (kg m^?3) in 2012 and 2013, respectively. These findings suggest that delay in planting date and the use of MAD = 60% treatment in Mediterranean-type region such as Golestan, Iran, can be useful in saving water that is highly important in such regions.     

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.     

Influence of humic acid and salicylic acid on yield,fruit quality,and leaf mineral elements of strawberry (Fragaria × Ananassa duch.) cv. Camarosa

A greenhouse experiment was conducted to evaluate the effects of foliarly-applied Humic Acid (HA) and Salicylic Acid (SA) on strawberry (Fragaria × Ananassa cv. Camarosa). On average, HA applications, regardless of concentration, increased overall yield, Soluble Solids Concentrations (SSC), Titratable Acidity (TA), vitamin C, red tone (a*), leaf potassium (K), phosphorus (P), calcium (Ca) and magnesium (Mg) while had no effect on pH and fruit luminosity (L*). In contrast, fruit from the untreated control tended to have higher Total Antioxidant Capacity (TAC) and SSC: TA ratio than HA-treated plants. Application of SA significantly increased yield, vitamin C, SSC, SSC: TA ratio, TAC, a*, leaf P and Ca while had no effect on TA, fruit size, L* and pH. In general, application of either HA at 25 mg L¹ or SA at 2 mM resulted in better strawberry performance than did other rates of these compounds.     

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

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 $\text{N}\text{Ca}$ was positively correlated with internal ethylene in MM 106, M 7 and OAR 1, while fruit $\text{K}\text{Ca}$ 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.     

Relationship of growth parameters and nutrients uptake with canola (Brassica napus L.) yield and yield contribution at different nutrients availability

A field experiment was conducted to evaluate the effect of different nutrients on canola (Brassica napus L.) growth parameters, nutrient uptake and ultimately on seed yield. For this purpose a split plot experimental design, with 10 treatments in 4 replications was carried out in 2004-2005, in silt-clay soil at Baiecola Agricultural Research Station, Mazandaran Iran. Canola seed yield, growth parameters (CGR, LAI, RGR and NAR), dry matter accumulation and HI and nutrient content of the leaf were examined. NPK fertilizers together with S and Zn, singly or in combination were applied. The results showed that at treatments T5 (NP), T8 (NPK), T9 (NPKS) and T10 (NPKZn) the higher seed yield (> 2600 kg ha(-1)) coincided with TDM > 880 g m(-2) the peak CGR > or = 13.9 g m(-2) day(-1) and the maximum LAI > or = 4.1. The higher seed yield at T5, T8, T9 and T10 coincided with higher concentrations of nutrients: N, P, K, S and Zn in leaf at flowering having > or = 3.40%, > or = 0.25%, > or = 1.53%, > or = 110 ppm and > or = 22.7 ppm, indicating substantial levels of translocation of nutrients at various stages of plant growth and higher number of pods per plant (> or = 179). Combined application of NPKZn at T10 resulted in maximum seed yield (3090 kg ha(-1)), coinciding with the maximum number of pods per plant (230), maximum TDM (1043 kg ha(-1)), maximum CGR (20.09 g m(-2) day(-1)) and maximum LAI (4.69).     

Saffron Daughter Corms Formation,Nitrogen and Phosphorous Uptake in Response to Low Planting Density,Sampling Rounds,Vermicompost and Mineral Fertilizers

Higher planting densities increase flower yield of saffron during the initial years; however, increase in population may have a negative effect on daughter corms, through increasing competition for nutrients. Accordingly, lower densities result in more desirable daughter corms for future planting. To investigate the effect of planting density, vermicompost and mineral fertilizers on daughter corms formation, and nitrogen (N) and phosphorus (P) content in the corms during different phenological stages, a three-year field experiment was conducted as factorial-split layout based on randomized complete block design with three replications, at Faculty of Agriculture, Ferdowsi University of Mashhad, Iran. The experiment consisted of 12 main plots [planting density (30, 60, 90 and 120 corms m^?2) × fertilizer sources (vermicompost 10.2 t ha^?1, mineral fertilizer including N 225 kg ha^?1 + P 129.08 kg ha^?1 and control)] and 15 subplots (15 sampling rounds; during the first, second and third growing seasons). During all stages of sampling, N and P content in large-sized daughter corms was significantly higher compared with middle and large-sized daughter corms. Application of vermicompost significantly increased the number, weight, N and P contents of medium and large daughter corms per plant than mineral fertilizer. Increase in plating density caused a significant reduction in number, weight, N and P content in the medium and large sized daughter corms per plant. Overall, the results suggest that lower densities and vermicompost application should be scheduled in mother corms production programs.     

Association between ABCB1-T1236C polymorphism and drug-resistant epilepsy in Iranian female patients

Background: One third of epileptic patients are resistant to several anti-epileptic drugs (AED). P-glycoprotein (P-gp) is an efflux transporter encoded by ATP-binding cassette subfamily B member 1 (ABCB1) gene that excludes drugs from the cells and plays a significant role in AEDs resistance. Over-expression of P-gp could be a result of polymorphisms in ABCB1 gene. We studied the association of T129C and T1236C single-nucleotide polymorphisms (SNP) of ABCB1 gene with drug-resistant epilepsy in Iranian epileptics. Methods: DNA samples were obtained from 200 healthy controls and 332 epileptic patients, of whom 200 were drug responsive and 132 drug resistant. The frequencies of the genotypes of the two SNP were determined by polymerase chain reaction followed by restriction fragment length polymorphism. Results: No significant association was found between T129C and T1236C genotypes and drug-resistant epilepsy neither in adults nor in children. However, the risk of drug resistance was higher in female patients with 1236CC (P = 0.02) or CT (P = 0.008) genotype than in those with TT genotype. The risk of drug resistance was also higher in patients with symptomatic epilepsies with 1236CC (P = 0.02) or CT (P = 0.004) genotype than in those with TT genotype. The risk of drug resistance was lower in patients with idiopathic epilepsies with 129TT genotype (P = 0.001) than in those with CT genotype. Conclusion: Our results indicate that T1236C polymorphism is associated with drug resistance in Iranian female epileptic patients. Replication studies with large sample sizes are needed to confirm our results. Key Words: ATP-binding cassette subfamily B member 1 (ABCB1), Drug-resistant epilepsy, Single nucleotide polymorphism     

Monitoring and modeling temperature variations inside silage stacks using novel wireless sensor networks

By monitoring silage temperature at different locations inside silage stacks, it is possible to detect any significant increases in temperature occurring during silage decomposition. The objectives of this study were: (1) to develop novel noninvasive wireless sensor nodes for measuring the temperature inside silage stacks; (2) to design a suitable sensor protection housing that prevents physical and chemical damage to the sensor; and (3) to mathematically model temperature variations inside a silage stack, using system identification techniques. The designed wireless nodes were used to monitor temperatures in a full-sized silage stack over 53 days. Results showed that the wireless sensor nodes accurately monitored the temperature inside the silage stack at depths of 25 and 50 cm and reliably transmitted the measured data through the network; between 98.9% and 99.4% of the packets disseminated from the sensor nodes were successfully delivered to the gateway. The reliable performance of the network confirmed the correct choice of network characteristics (i.e., frequency range of 433 MHz, a handshaking communication protocol, and 10 mW transmission power). The designed sensor housings were capable of withstanding the high loads that occurred during ensiling, storage, and feed-out. Mathematical models estimating the relations between the silage temperatures (at depths of 25 and 50 cm) and air and soil temperatures were obtained. Black-box modeling using the prediction error method (PEM) was selected as the identification method. Among different black-box models such as ARX, ARMAX, output-error (OE), and Box–Jenkins (BJ), with different model orders, a third-order Box–Jenkins model structure gave the best performance in terms of prediction accuracy. The success rate of the models proposed for silage temperature prediction ranged between 90.0% and 94.3%. Furthermore, there was no significant autocorrelation remaining in the residuals. The results of this study indicate that the designed wireless sensor nodes could potentially be used for detecting silage decomposition processes and improving the efficacy of silage conservation systems.     

Quality and elemental content of citrus fruit from exposed and internal canopy positions 1

Quality and elemental content of fruit from internal tree canopies were compared with those from external canopy positions in 4 citrus varieties: ‘Kinnow’ mandarin; ‘Redblush’ grapefruit; ‘Valencia’ orange; and ‘Lisbon’ lemon. Fruit weight, total juice per fruit, peel fresh and dry weight, and rind thickness of fruit from internal canopies of all 4 varieties were significantly higher compared with external fruit. Mandarin, grapefruit, and orange fruit from external canopies had higher soluble solids and specific gravity. Fruit from internal canopies of all varieties had generally higher peel concentrations (% dry weight) of N, P and K due to a dilution effect, while the opposite condition existed in mandarin when these elements were expressed on a percent fresh weight basis. Peel Mg and S from external fruit were higher in all varieties, expressed as percentages of either dry weight or fresh weight. Nitrogen content of mandarin and orange juice and Ca content of grapefruit and lemon juice from external fruit were significantly higher compared to those from internal canopy fruit. Elimination of fruit quality and mineral variations as a result of canopy positions is recommended by the means of cultural practices.