peyman abbasi

Edible coatings have been used to preserve, improve the quality and increase longevity of fruits and vegetables. The aim of this study was to investigate the effect of two types of edible coatings on based natural gum on qualitative attributes and storage life of grape cv. Hosseini as a factorial experiment and completely randomized design. Fruits were immersed in Arabic gum (0, 5, 10 and 15 concentrations) and Almond gum (0, 3, 3.5 and 4 concentrations) in tree sampling times (at harvvest, 15, 30 and 45 day).  All treated fruits were stored in a cold storage in 1±0.5 °C and 95% RH for 45 days. Every 15 days, the percentage of weight loss, firmness, ripening index (TSS/TA), total phenol, vitamin C, amount of photosynthetic pigments, total carbohydrate and antioxidant activity of the skin and flesh of berries were measured. The results of the present study showed that coated samples had lower weight loss and better firmness than uncoated samples. Also, coated fruits could be able to preserve vitamin C, total phenol, pigments and antioxidant activity of the skin and flesh of berry better and the amount of TSS/TA and total carbohydrates increased lower than control samples. It is concluted that the concentrations of %5 Arabic gum and %3.5 Almond gum had a significant defference in most of the parameters with other concentrations and the qualitative and sensual attributes of berry could be preserved better than other treatments and extended fruit storage life.

Fertilization is one of the most important management tools in horticulture playing an important role in nutrition of fruit trees in order to improve the yield and quality. A factorial randomized complete block design experiment with 3 replications was conducted to investigate the effects of potassium sulphate (0, 50, 100 and 150 g/tree) and iron chelate (0, 10, 20 and 30 ml/tree) during Red Delicious apple tree growth. Some traits including branch length, chlorophyll index, fruit length and width, fruit weight, fruits number, leaf area index and concentration of some nutrients in leaves were measured. The results showed that potassium sulfate and iron chelate improved all growth traits. Potassium sulfate and iron chelate showed a positive and significant increase in yield. With increase in concentration of potassium sulfate, the amount of phosphorus and potassium in leaves was increased, while iron chelate decreased the amount of phosphorus. The highest amount of magnesium was observed in the absence of potassium sulfate treatment and treatment with 30 cc of iron chelate. The highest amount of iron was observed in the case of treatment with 20 and 30 cc of iron chelate with no potassium sulphate application. Also, with the application of potassium sulfate fertilizer, the amount of calcium and copper in the leaves was decreased. Fertilization had no significant effect on the concentration of nitrogen, zinc and manganese in the leaves.

In this research, effects of Na+ ion on Nitrogenous Organic Bases (NOB) in the nucleic acids by using of a new index. This index is according to Electric Field Gradient (EFG) in the middle of bond and evaluated as a reference by corresponding cyclic same compounds. The studied molecules were Adenine, Guanine, Cytosine, Thymine and Uracil that has been investigated. The trend of changes of aromaticity by putting Na+ in the middle of cycle and change of distance according to degree of Angstrom (Å). It has been used Density Functional Theory (DFT) as a method for geometrical optimization Beck 3 Lee Yang Parr (B3LYP) in 6-311++G** and 6-31G standard basis set. These calculations have been done in two steps. In the first step, it has been calculated electric field gradient in the middle of bond in absence of Na+ (EFG0) and in the second step in presence of Na+, it has been calculated in 1Å distance of middle of bond without Na+ (EFG0.5) and with Na+ that compared amount of aromaticity between EFG0 and EFG0.5 in 6 distance (d = 0.5, 1, 1.5, 2, 2.5 and 3 Å).