مجله علوم و فنون باغبانی ایران
سال چهاردهم شماره 4 (زمستان 1392)

Rose plants cvs. „Sweet Water‟ and „Sorbet Avalanch‟ were foliar sprayed twice by salicylic acid and methyl jasmonate in stage of leaf color change. Distilled water was used as control. Flowers were placed in erlens containing 3% sucrose after harvest. The results showed that „Sweet Water‟ had more vase life than „Sorbet Avalanch‟. The response of cultivars to treatments was not similar for some recorded parameters. „Sweet Water‟ treated with 0.2 mM methyl jasmonate had the longest vase life, but in „Sorbet Avalanch‟ this treatment caused the shortest vase life. The highest total stem carbohydrate was observed in „Sorbet Avalanch‟ treated with 0.01 mM salicylic acid and in „Sweet Water‟ treated with 0.2 mM methyl jasmonate. Also, 0.2 mM methyl jasmonate caused the least total stem carbohydrate content in „Sorbet Avalanch‟. The highest soluble protein content in petals was measured in „Sweet Water‟ treated whit 0.2 mM methyl jasmonate and „Sorbet Avalanch‟ treated whit 0.1 mM methyl jasmonate.

This research was conducted to test the effects of pruning systems for hazelnut cultivation and production in north of Iran. The experiment was carried out for three years in Astara Research Station. Three training systems (one trunk, two trunks and four trunks) were used on three cultivars („Ronde-Dopimont‟, „Fertile‟, „Segorbe‟) and a native genotype (Geird). The experiment was conducted factorially using randomized complete block design with three replications. Trees were seven years old and traind in three forms of one, two and four trunk from early growth. Five vegetative traits, including trunk diameter growth, annual growth, canopy height, canopy diameter and canopy volume were measured. The quantitative nut traits; nut weight, kernel weight, kernel percentage, empty nut percentage, yield per tree and total yield were recorded for three years. Results showed that the growth traits of fruits were affected by cultivar and training systems. The training system of one trunk increased the totalfruit yield and the quantitative traits related to nuts, while the four trunks system resulted in more vigorous vegetative characteristics compared with one or two truck.

Narcissus (Narcissus tazetta L.) is one of the cut flowers having short vase-life. A completely randomized design experiment with 3 replications was carried out to assess the effect of antioxidant compounds on some qualitative and quantitative characteristics of this flower. Arginine (Arg), putrescine (Put), proline and sodium nitroprusside (SNP) were used at 1, 5 and 10 μM along with control treatment (distilled water). The highest vase-life was obtained with 1 μM SNP and 5 μM Put which increased vase-life for 3 days compared with control. The lowest electrolyte leakage was obtained with 1 μM SNP and 5 μM Put which reduced electrolyte leakage by 45% and 51%, respectively in comparison with control. The results also, indicated that vase-life was increased with SNP (1 μM), Put (1 and 5 μM) and proline (1 and 5 μM) compared to control. This increase in vase-life was accompanied with significant increase in the activity of antioxidant enzymes and PAL, while polyphenol oxidase (PPO) activity was significantly decreased. Accordingly, it appears that the applied compounds reduced free oxygen radical, preserved cell membrane integrity, increased phenolic compound synthesis and reduced PPO activity which ultimately resulted in higher quality of narcissus cut flowers.

Water deficit is a major limiting factor for turfgrass growth in arid and semi-arid regions. Thus, in this study the drought tolerance of two turfgrass species, creeping bentgrass (Agrostis stolonifera var. „Palustris‟) and tall fescue (Festuca arundinacea schreb var. „Ky 31‟) was investigated by sodium nitroprusside (material that release nitric oxide (NO)). A facrtorial experiment was carried out in completely randomized design with three replications. Three factors including; two turfgrass species, four levels of nitric oxide and four levels of drought stress. The results showed that drought stress and NO treatment had not significant effect on shoot length of both grass species. Drought stress significantly increased electrolyte leakage, but NO treatment reduced electrolyte leakage in drought stress conditions. In both turfgrass species, leaf relative water content decreased with increasing soil suction, but NO treatment maintained the leaf relative water content higher than untreated plants. In tall fescue NO significantly reduced peroxidase activity during drought stress when compared to the untreated plants, but in creeping bentgrass NO significantly increased activity of this enzyme. In both turfgrass species, superoxide dismutase activity of leaves decreased with increasing soil suction, however, different concentrations of NO significant increased the activity of this enzyme when compared to control. Finally, it appears that the nitric oxide by supresing free oxygen radicals and increasing antioxidant enzymes activity decreased electrolyte leakage and increased leaf relative water content, and as a result decreased drought stress damage in the turfgrasses.

In this study, the effects of cultivar, plant growth regulators, various culture media (single and double layer), temperature stresses and carbohydrate sources (sucrose, glucose, maltose and their combinations) on callus/embryo formation from microspors in four rose cultivars i.e. „Elegant‟, „Velvet‟, „Candy‟ and „Exotic‟ were investigated. According to the results two rose cultivars „Exotic‟ and „Velvet‟ and combination of BAP (0.5 and 1 mg l-1) and IAA (4 and 8 mg l-1) significantly induced callus higher than other treatments. Frequency of callus induction in double layer media especially in MS and Nitsch and Nitsch as lower media with upper AT3 (with sucrose and lactalbomin hydrolysate) liquid medium (MS/AT3-SL and NN/AT3-SL) was higher than single layer solid medium. Examination of the effects of temperature shocks on callus induction did not improve callus formation campared to control (25°C). Results also showed that callus formation in sucrose-containing Nitsch and Nitsch media was significantly higher than other carbohydrates. In the present study, for the first time, seven embryos were formed in „Exotic‟ cultivar by shed microspore culture in double layer media which were regenerated successfully and ploidy level analysis confirmed that they were haploids.

Mineral composition in harvested fruits can influenced fruit tissue firmness and postharvest life. In this study fruits were harvested from 70 different commercial kiwifruit orchards on 10 weeks after full bloom and the commercial maturity stage. After harvest, fruit mineral composition such as nitrogen, potassium, phosphorus, calcium, magnesium and dry matter were measured. Tissue firmness was also measured on mature fruits. Thereafter, mature fruits were transferred to storage at 0 ºC and 90-95% relative humidity and after 105 days fruit tissue firmness was evaluated. The regression model showed that, positive correlation existed among fruit tissue firmness at the end of storage with tissue firmness and dry matter of mature fruit at harvest time but a negative correlation with N+K/Ca ratio, phosphor and nitrogen content of mature fruit. Also cluster analysis was divided studied orchards into two main groups. Based on t test fruit tissue firmness at the end of storage in first group orchard was less than second group. In addition, In first group concentration of potassium, phosphorus, nitrogen, N/Ca, N+K/Ca, K/Ca and K+Mg/Ca ratios was higher than the second group, but dry matter in fruitlets and fruits, calcium concentration of mature fruits and fruit tissue firmness at harvest was lower. The discriminate function analysis showed that variables of tissue firmness at the end of storage, ratio of N+K/Ca, K/Ca, N/Ca, K+Mg/Ca had the highest correlation with the discriminant function. In conclusion, mathematical models can be used for prediction of postharvest behavior and storage quality in kiwifruit.

In this research subsurface drip irrigation method with different salinity levels and it‟s effects on quality and yield parameters of tomato and also irrigation management methods including m1 and m2 (m1 is alternative irrigation with fresh water and saline water, m2 is saline water in first half of each irrigation event and fresh water in the second half) have been compared. The experiment was conducted in 320 m2 area including 30 plots. Drippers were placed in 15 cm soil depth and in order to consider the interaction salinity levels and management strategies, split plot design with three replications was used in which management strategies (m1 and m2) were main plots and subplots were different levels of salinity including 0.68, 2, 4, 6, 8 ds m-1 (s0, s1, s2, s3, s4, respectively). Results showed that tomato yield was decreased with increasing irrigation water salinity and the highest and lowest yields were in the m2s0 (52.44 ton ha-1) and m1s4 (23.363 ton ha-1) treatments, respectively. Also average yield in m1 strategy was 17.77% less than m2 strategy. Also in this research the other qualitative parameters such as fruit density, fruit water content, texture strength, sodium, calcium and nitrogen concentrations and L, a and b colorimetric factors were measured. With increasing irrigation salinity, the sodium concentration in tomato fruits was increased, but water content and L factor, were decreased. The variations in nitrogen, calcium, density, fruit number, fruit weight and a and b factors were not significant. In general, from different aspects, the m2 management method was better than m1 management in control of salinity effects.

This study was carried out to evaluate the effect of 2h pulse treatment with silver nanoparticles (0, 4, 25, 75 and 125 mg l-1), then storing cut flowers in sucrose solution (0, 2 and 3%) on some of the postharvest physiological parameters and vase life of cut rose cv. „High and Magic‟. The experiment was done as a factorial in a completely randomized design with 3 replications. Cut flowers were maintained in temperature of 23 ± 2º C, relative humidity 60 ± 5% and a light intensity of 12 μmol m-2 s-1 (cool white fluorescent lamps) with 12 hours duration until the end of vase life. Results showed that 125 mg l-1 silver nanoparticles without sucrose or with 2% sucrose treatment showed the best results in controlling bacteria. Pulse treatments with silver nanoparticles at all concentrations improved solution uptake, and holding relative fresh weight. However, the best results were obtained at 125 mg l-1 silver nanoparticles, and 2% sucrose where, ion leakage of petal cells also reduced. Cut flowers pulsed with distilled water with or without sucrose had least vase life and showed significant difference with ones was pulsed with silver nanoparticles (with or without sucrose). Among different concentrations of nanosilver, the concentrations of 75 and 125 mg l-1 with or without sucrose treatment had more effect in improving vase life period than 25 mg l-1 with the same conditions.

Drought stress is one of the most important factors limiting the development of orchards in Iran. There is a considerable genetic variation for drought tolerance among olive cultivars. Therefore, an experiment was conducted to screen 12 olive cultivars for drought tolerance using a factorial experimental based on completely randomized design with three replications. Drought stress treatments applied was based on “allowed water depletion” at three levels 90, 55 and 35% as control, moderate and severe stress respectively on own rooted one-year-old seedlings for 60 days. Results showed drought stress reduced shoot growth and leaf gas exchange parameters in all cultivars. The „Mission‟ and „Konservolia‟showed lower shoot growth reduction and higher levels of transpiration and stomatal conductance. Ratio of root/shoot dry weight increased in all cultivars under stress conditions and higher ratios were observed in „Mission‟, „Konservolia‟, „Arbequina‟ and „Roughani‟. Leaf proline and soluble carbohydrates contents increased in response to drought stress. There was considerable variation among cultivars for prolineand cvs. „Arbequina‟ and „Fadak‟ showed higher contents. Our finding showed „Mission‟, „Konservolia‟, „Manzanilla‟ and „Arbequina‟were more tolerant to droght than the rest.

An experiment was conducted to survey the effects of fosnotren amino acid, fulvic acid and brassinolide on the yield and fruit quality of rain-fed grapevine (Vitis vinifera L. cv. „Khalili‟) in Bavanat and Shiraz (Akbar-Abad) regions. The lay out was a randomized complete block design (RCBD) in two years with three replications and five vines per each plot. Treatments consisted of control, foliar applications of fulvic acid (3%), fosnotren amino acid (2.5 mg l-1), brassinolide (0.4 mg l-1), fulvic acid (3%) + fosnotren amino acid (2.5 mg l-1) + brassinolide (0.4 mg l-1) in three different times before and after flowering, and in the early stage of berry development, and soil application of brassinolide (0.2 mg l-1, 5 liter vine-1) in before bud break. The results showed that chemicals reduced bloom drops and increased flower intensity, fruit set, fruit size, sugar, total soluble solid and improved fruit quality and fruit color, and includes synchronise ripening of berrys. The highest fruit yield obtained from combination of foliar application of the compounds with 194.3% yield increase in comparison with control. Foliar applications of fosnotren amino acid and fulvic acid increased fruit yield by 66.4 and 44.9 in comparison with control, respectively. However, based on the results, foliar application of the 3 compounds in all stages is recommended.