نشریه پژوهش های میوه کاری
سال یکم شماره 1 (بهار و تابستان 1395)

In order to evaluate the effects of BA on thinning, qualitative characteristics and antioxidant capacity in plum cv "Golden Drop", this research was conducted in Research Station of Agriculture, Tabriz University. A randomized complete block design (RCBD) with 5 treatments of BA (0, 50, 75, 100 and 125 mg / l) and 4 replications was arranged. Treatments were applied 14 days after full bloom on the selected branches. The thinning percentage and fruit quality parameters including total soluble solids (TSS), vitamin C, fruit diameter, length, volume, total flavonoids, total phenolic compounds and antioxidant capacity were measured. Results showed that BA significantly increased the amount of fruit thinning fruit, length, diameter, volume, soluble solids, vitamin C, titratable acidity and antioxidant capacity. Fruit firmness, total flavonoids and, total phenolic compounds were not affected by BA treatments. The highest fruit thinning belonged to 125 mg/L BA. In conclusion, BA caused significant thinning intensity and improved fruit quality of plum cv. "Golden Drop".

In order to study the effect of foliar application of salicylic acid on Bidaneh Sefid grape cultivar under boron toxicity, a randomized complete block design experiment with three replications. Was conducted two year saplings of grape (Bidaneh Sefid cultivar) were treated for three months with different concentrations of boric acid (application with nutrient solution) (at 0.2 (control), 15, 30 mg/L) and Salicylic acid (foliar application) (at 0, 1.5 mM). The results of this experiment showed that contents of malondialdehyde (MDA), proline, electrolyte leakage and total protein content were increased in saplings treated with boron. The electrolyte leakage was increased to 63.16% at a concentration of 30 mg/l of boron. With increase in boron toxicity, guaiacol peroxidase enzyme activity was reduced. Saplings spraying, saplings with salicylic acid increased the antioxidative enzyme activity. The findings of this study suggest that boron toxicity can increase oxidative damage and foliar application with salicylic acid may reduce oxidative damage caused by the boron stress in Bidaneh sefid grape cultivar

In order to study the effected plant density and substrate medium on growth, yield and qualitative characterssticsof strawberrycv. Selva, an experiment was conducted in greenhouse of West Azerbaijan Agricultural and Natural Resources Research Center, Iran. This stuay was conducted in a factorial experiment based on completely randomized design with 4 replications. Studied factors in this research were included plant density (10 and 20 plants per m2) and substrate medium contains: coco coir, perlite, coco coir + perlite (1:1), coco coir + perlite (3:1) coco coir + perlite (1:3). Results indicated that the number of leaves, crowns, flowers and fruits per plant, leaf area, TSS and pH of fruit juice, dry weight of root and yield per plant in 10 plants per m2 were higher than 20 plants per m2 and the number of days to flowering showed a significant decrease. The two plant densities did not have significant difference in yield per m2. Substrate medium had a significant effect on leaf area, numbers of roots per plant, dry weight of shoot and root, TSS and TA and yield per m2. The most and least yield per m2 with 1.87 and 1.17 kg were recorded in coco coir and perlite respectively.

Mineral nutrition of walnut trees (Juglans regia L.) via foliar application is one of the most important techniques to improve the fruit quality and quantity. Therefore, foliar application of urea and boric acid on growth characteristics, fruitset and yield of "Poost Kaghazi" walnut trees. Was studied the experiment was carried out in bud swell stage as a randomized complete block design with seven treatments and four replications. Treatments were, urea (at 0, 0.5 and 1 %), boric acid (at 0, 2000 and 4000 ppm) and combined treatments of urea and boric acid. Results showed that urea at 1% and boric acid at 4000 ppm improved the growth characteristics, fruit set and yield, therefore, the yield was increased to 174 g dry-wieght per shoot. Also, the combined treatment of urea and boric acid increased the amount of photosynthetic pigments, reduced sugars and total protein. The results of leaf analysis showed that the combined treatment of urea 1% and boric acid 4000 ppm increased the leaf nitrogen concentration to 1.9 % and boron concentration to 65.6 ppm compared to control trees (1.1% nitrogen and 26.2 ppm boron). It was also found that the combined treatment of urea 1% and boric acid 4000 ppm was the most effective in improving the quality and quantity of walnut crop. According to the results, we can suggest that combined treatments of urea and boric acid may improve the yield and growth characteristics of "Poost Kaghazi" walnut trees.

In order to study the effect of potassium phosphite and boric acid on fruit set of different grape (Vitis vinifera L.)cultivars,two separate experiments were arranged in a factorial design based on a completely randomized design with 3 replications on orchard conditions. The first experiment was involved foliar application of potassium phosphate (0, 1500 and 3000 mg/L) on Askari, Sefidali and Razeghi cultivars and in second trail spraying of boric acid (0, 1500 and 3000 mg/L) after 50% anthesis on inflorescence were done on same cultivars. The total number of flowers, number of opened and closed flowers, number of fallen flowers, and the number of flowers after abscission and fruit set in all three cultivars were measured. The results showed that there was a significant difference at P≤0.01 for all or some of traits between Askari, Sefidali, Razeghi cultivars and between three concentrations of potassium phosphate and boric acid. The lowest number of flower abscission (44.69 and 51.85) and highest fruit set (74.58 and 77.60%) were obtained from potassium phosphate and boric acid treatments with 3000 mg/L, respectively. According to the results of this study and also regarding to other important traits and experiment conditions, potassium phosphate and boric acid fertilizers at 3000 mg/L after 50% anthesis are suggested due to the positive effects on increases fruit set and crop yield as.

Drought is one of the most important factors limiting plant growth. Due to climate changes, the orchards are at risk of drought stress in our country. In this study, we investigated the response of Sour cherry cv. "Mykrez" to different levels of water stress. A randomized complete block design experiment with three water stress treatments (control, -5 and -10 bar based on soil water tension) was performed. Growth traits, including growth rate of branches, number of leaves and leaf area and physiological parameters including leaf relative water content, proline and total carbohydrates, total soluble carbohydrates, membrane stability index and leaf chlorophyll content (a, b and total) were measured. The results showed that the growth of branches, number of leaves and leaf area were significantly decreased with increase in water stress level and there was a significant difference between the three treatments. Proline and total soluble carbohydrates were increased in – 5 bar and -10 bar drought stresses compared with the control. Total carbohydrates were significantly reduced in – 5 bar and -10 bar compared to control. RWC and chlorophyll (a, b and total) were decreased in water stress treatments. Based on the findings of this study, it seems that "Mykrez" Sour cherry cultivar increases leaf proline and total soluble carbohydrates content in order to overcome the adverse effects of water stress.