Relationship between Balanced Fertilization and Healthy Agricultural Products (A Review)

Based on World Health Organization (WHO) report, our society’s health ranks 123 among 192 countries. Unfortunately, this ranking position is very low and its main reason is malnutrition due to imbalanced fertilization. Although more than 85% of Iranian people are not hungry, about 90% of them are suffering from cell hunger, because agricultural authorities and hence producers do not pay attention to food security. According to the latest information, about 86.5% of applied fertilizers in our country appertain to urea and triple super phosphate. In fact, this is an alarming issue in respect to the production of healthy agricultural products and it remains a threat to food security. At present, a total subsidy of more than 7,000 billion rials is paid for nitrogen (N) and phosphate (P) fertilizers. Whereas, it should be considered that, firstly, the efficiency of these fertilizers, due to different reasons such as mismanagement and existing subsidy level, is low and, secondly, the overuse of these fertilizers causes the accumulation of nitrate (NO3) and cadmium (Cd) in agricultural products. Furthermore, according to the law of minimum, the overdosed fertilizers do not have any special positive effect on sustainable production and society’s health. Paying for such high-cost subsidy just for N and P-fertilizers has caused farmers to overuse and waste these fertilizers in the country and moreover not having any tendency to apply biologic, organic and micronutrient fertilizers. Whereas, the application of these fertilizers, beside their adaptability with the environment, has a very positive effect on the human health. Therefore, at this time scientific management of production and application of all kinds of fertilizers is inevitable. In this case, by improving the quality of all types of fertilizers, and following the principle of balanced fertilization, besides achieving the desired yield increase, the quality of agricultural products will be enhanced and the level of society’s health will be promoted automatically. Furthermore, there is a close and positive relationship between balanced fertilization and production of healthy agricultural products. The authorities of  the Ministry of Jehad-e- Agriculture are supposed to consider this important principle for a) supplying suitable kinds and amounts of fertilizers during  application seasons in producing agricultural products; b) banning  the act of burning the plants' residues; c) considering the rules of balanced fertilization; d) enrichment of agricultural products on the farm; e) scientific management of production and application of all kinds of fertilizers; f) implementing the criteria set for Article 61 of the Fourth Development Plan; g) avoiding the import of P-fertilizers which contain Cd in excess of 25 mg/kg and h) removing the subsidy on N and P-fertilizers in order to increase the yield and quality of agricultural products and enhance society's health

The interaction of boron with goethite: Experiments and CD-MUSIC modeling

Boron (B) is an essential element for plants and animals growth that interacts with mineral surfaces regulating its bioavailability and mobility in soils, sediments, and natural ecosystems. The interaction with mineral surfaces is quite important because of a narrow range between boron deficiency and toxicity limits. In this study, the interaction of boric acid with goethite (a-FeOOH) was measured in NaNO3 background solution as a function of pH, ionic strength, goethite and boron concentration representing as adsorption edges and isotherms. Boron adsorption edges showed a bell-shaped pattern with maximum adsorption around pH 8.50, whereas adsorption isotherms were rather linear. The adsorption data were successfully described with the CD-MUSIC model in combination with the Extended Stern (ES) model. The charge distribution (CD) of inner-sphere boron surface complexes was calculated from the geometry optimized with molecular orbital calculations applying density functional theory (MO/DFT). The CD modeling suggested dominant binding of boric acid as a trigonal inner-sphere complex with minor contributions of a tetrahedral inner-sphere complex (at high pH) and a trigonal outer-sphere complex (at low pH). The interpretation with the CD model is consistent with the spectroscopic observations. © 2010 Elsevier Ltd

The Effect of Bio-fertilizer and Chemical Fertilizers (Phosphate and Zinc) on Yield and Yield Components of Two Cultivars of Bean (Phaseolus vulgaris L.)

Introduction: Use of unbalanced chemical fertilizers especially P, having low absorption efficiency and low solubility compounds with soil components, has resulted in the production and use of bio-fertilizers (17, 23 and 29). Bio-fertilizer is a preservative material consisting of one or several specific beneficial micro-organisms or their metabolic products used to supply plant nutrients and development of root systems (29). There are a lot of micro-organisms in soil capabling help to plant nutrition and uptake of nutrient elements in different ways that can be mentioned by the dual symbiotic relation between micro-organism and plant. Mycorrhizal fungus and plant growth promoting rhizobacteria (PGPR) such as Azotobacter and Pseudomonas are able to increase uptake of nutrient elements particularly when they are applied with others and hence they increase the yield of different crops (12, 14; 24 and 30). P solubilizing fungus and bacteria facilitate uptake of slowly diffusing nutrient ions such as P, Zn and Cu and increase their availabilities usually by increasing volume of soil exploited by plants, spreading external mycelium, secreting organic acids, production of dehydrogenase and phosphates enzymes and reducing rhizosphere acidity (9, 15, 19, 23 and 26). The main beneficial use of micro-organism is increasing of host plant growth. It can be done with increase of nutrient elements uptake. The main objective of this study was to evaluate the effect of P and Zn bio-fertilizers on yield, yield components and shoot nutrient elements in two cultivars of bean for the first time in the Chaharmahal-va- Bakhtiari province. Material and Methods: This field experiment was carried out as a factorial in a randomized complete block design (RCBD) with three replications. The treatments of this research consisted of two cultivars of Chiti bean (Talash and Sadri), four levels of P (P0: Control, P1: Chemical fertilizer on the basis of soil test, P2: 50 percent of recommended P + bio-fertilizer (P), and P3: bio-fertilizer (P)), three levels of Zn (Zn0: Control, Zn1: 50 kg ha-1 Zinc sulphate, and Zn3: bio-fertilizer (Zn)). Bio-fertilizer (P) treatment consisted of mycorrhizal and five strains of Azotobacter chroococcum. Bio-fertilizer (Zn) treatment consisted of Pseudomonas aeruginosa strain MPFM and Pseudomonas fluorescent strain 187. Grain inoculation (5%) was done in shadow and after drying, inoculated grains were immediately cultivated. Two g of mycorrhizal fungus was applied at the base of the grain hole just prior to sowing. Chemical fertilizers were applied from TSP at a rate of 100 and 50 kg ha-1 in P1 and P2 respectively, 50 kg ha-1 ZnSO4.7H2O in Zn1 and 50 kg ha-1 urea as a starter before planting. The size of each plot was 3 × 4 meters. Statistical analysis was done with SAS) statistical software. Duncan’s multiple range test was used to separate means. Results and Discussion: The results revealed that there were significant differences between the two cultivars on seed yield, number of seeds per pod, 100 seed weight and concentrations of nitrogen (N), potassium (K), and Zn, but there was no significant difference between the other parameters. P treatment showed a significant effect on the examined parameters except the number of seeds per pod. The highest content of yield (3446 kg ha-1) was observed in P2 treatment (18.5% seed yield increase). Zinc treatment also had a significant effect on the parameters being studied except the number of seed per pod and manganese (Mn) concentration. The maximum seed yield (3339 kg ha-1) was monitored in Zn1 and Zn2 treatments. The effect of interactions between P and Zn was significant on the number of pods per shrub, 100 seed weight and K concentration, but it was not significant on the other parameters. However the highest content of seed yield (3520 kg ha-1) was obtained from P2Zn1 (32.5% seed yield increase) treatment. Our results were similar to findings of other researchers (1, 3, 12, 15, 17, 26 and 30). They reported that dual inoculation increases plant productivity. In this study, phosphate and Zn bio-fertilizers caused an increase in yield, yield component and shoot nutrient by increasing nutrient uptake, photosynthesis, growth hormones and creating favorable growth conditions. Also results showed that the consume of P fertilizers were decreased (50 percent) with proper integration of chemical and bio-fertilizers. These results correspond with the results of other researchers (17, 22, 23, 24 and 27). Conclusion: In this research proper integration of bio- and chemical fertilizers was shown to increase yield and yield components with increasing and improving P and other nutrients’ uptake in both bean cultivars. The result also indicated that combining bio and chemical phosphate fertilizers increased the efficiency of phosphate fertilizers by 50 percent. Sadri cultivar is a suitable cultivar for Chaharmahal-va- Bakhtiari province and regions with a similar climate. Keywords: Phosphorus, Zinc, Mycorrhizal fungi, Bean (Phaseolus vulgaris L.), Insoluble phosphorus and zinc solubilizer

Diffusion of neutral and ionic species in charged membranes: Boric acid, arsenite, and water

Dynamic ion speciation using DMT (Donnan membrane technique) requires insight into the physicochemical characteristics of diffusion in charged membranes (tortuosity, local diffusion coefficients) as well as ion accumulation. The latter can be precluded by studying the diffusion of neutral species, such as boric acid, B(OH)30(aq), arsenite, As(OH)30(aq), or water. In this study, the diffusion rate of B(OH)30 has been evaluated as a function of the concentration, pH, and ionic strength. The rate is linearly dependent on the concentration of solely the neutral species, without a significant contribution of negatively charged species such as B(OH)4-, present at high pH. A striking finding is the very strong effect (factor of 10) of the type of cation (K+, Na+, Ca2+, Mg2+, Al3+, and H+) on the diffusion coefficient of B(OH)30 and also As(OH)30. The decrease of the diffusion coefficient can be rationalized as an enhancement of the mean viscosity of the confined solution in the membrane. The diffusion coefficients can be described by a semiempirical relationship, linking the mean viscosity of the confined solute of the membrane to the viscosity of the free solution. In proton-saturated membranes, as used in fuel cells, viscosity is relatively more enhanced; i.e., a stronger water network is formed. Extraordinarily, our B(OH)3-calibrated model (in HNO3) correctly predicts the reported diffusion coefficient of water (DH2O), measured with 1H NMR and quasi-elastic neutron scattering in H+-Nafion membranes. Upon drying these membranes, the local hydronium, H(H2O)n+, concentration and corresponding viscosity increase, resulting in a severe reduction of the diffusion coefficient (DH2O ˜ 5-50 times), in agreement with the model. The present study has a second goal, i.e., development of the methodology for measuring the free concentration of neutral species in solution. Our data suggest that the free concentration can be measured with DMT in natural systems if one accounts for the variation in the cation composition of the membrane and corresponding viscosity/diffusion coefficient