Iranian Journal of Horticultural Science
Year:2015 | Volume:46 | Issue:2|Papers Count:16

Seedless grapes are widely grown all over the world. Embryo rescue technique proved to be able to overcome the problem of embryo abortion in seedless grape breeding program. Since, the efficiency of this technique is not desirable, so a lot of efforts have been done in different directions in order to improve this technique. This study was conducted in two separate experiments in which chlormequat and putrescine were employed in different experiments. Cultivars of Yaghooti, Flame Seedless and Perlette were used as both female and male parents in both experiments. Clusters sprayed with different concentrations of chlormequat and putrescine 14 days before blooming. Ovules were excised from berries 45 days after pollination and cultured in NN medium supplemented with 3.0% sucrose, 0.2% activated charcoal and 6% agar. Embryos were removed from the ovules after 10 weeks and transferred onto MS medium supplemented with 2.0% sucrose, 0.2% activated charcoal and 6.5% agar. The results showed maternal and paternal genotypes, pre-treatment with chlormequat and putrescine had positive and significant effect on endosperm and embryos development, embryos germination and plant production. The use of cv. Perlette as female parent, cv. Yaghooti as male parent and pre-treatment with chlormequat and putrescine at 100 and 30 mg/L increased the percentage of measured traits.

Thinning operations is essential to produce quality products in peach cultivation. Inefficiencies due to the high cost of hand thinning and mechanical thinning increased tendency to chemical thinning. In order to study the effect of lime sulfur (6%, 8% and 6% twice), ammonium thiosulfate (20, 25, 20 mL/L twice) and Apogee regulator (300, 400 and 300 mg/L twice) as thinning agents on fruit quantitative and qualitative characteristics of peach ʻRed havenʼ, a research was carried out in a commercial orchard on selected uniform Six-year-old trees in Semirom, Isfahan, Iran in 2012-2013. Results showed that all of the treatments, but Apogee (300 and 450 mg/L) significantly thinned the fruits and reduced fruit set up to 65 percent. Treatments increased fruit weight, volume (45- 50 percent), total soluble solids (TSS) and color and also enhanced leaf area index (LAI). However, there was no significant differences among control and the treatments for total fruit acidity. Trees treated with ATS (20 ml/l twice) and lime sulfur (6% twice) showed relatively best of quantitative and qualitative characteristics.

Increasing product marketability and introduction of new cultivars for fresh consumption of apple is the world's most important breeding objectives. In this study, the qualitative and quantitative characteristics of the genotypes from cross between Red Spur and Golab-e-Kohanz apple cultivars were evaluated. A total of 19 traits including fruit attributes (firmness, fruit weight,...) and the tree traits (trunk circumference, flowering time,...) were evaluated for two consecutive years. Results of simple correlation analysis showed positive and negative correlations between some important characteristics such as fruit weight, diameter and length, ratio of sugars to acids, acidity (pH), flowering and maturity time and the time of leaf abscission in the fall. Some attributes such as the time of leaf abscission, fruit color, flowering time, titrable acids, annual growth of shoots, the ratio of sugar to acid and fruit weight showed the highest variation coefficients. While, the attributes including the fruit length to diameter ratio, total soluble solids, fruit diameter, pH of fruit juice and the maturation time had the lowest variation coefficients. In general, most evaluated genotypes in terms of the maturity time were early to midseason. During the study, a number of early genotypes with good quality and quantity of yield were determined.

In order to investigate the effect of cycocel on different growth aspects of two olive cultivars (Mary and Mission), a greenhouse experiment was conducted taking into account three factors of: cycocel at three levels (0, 500 and 1000 mg L-1), drought stress of three levels (irrigated at 5, 10 and 15 days intervals) and two olive cultivars (Mary and Mission) in a factorial experiment based on randomized complete block design of three replicates during four months. The results showed that both cycocel treatments decreased leaf area, increased leaf thickness, chlorophyll content and soluble sugars, but no significant difference in leaf temperature was observed compared with the control. High cycocel treatments (1000 mg L-1) increased proline and relative water content (RWC) compared with the other treatments. Also, results showed that increased periods of drought reduced leaf area, RWC, but increased leaf thickness, leaf temperature, chlorophyll content, proline and soluble sugars in both cultivars. In above-mentioned parameters, 'Mission' showed higher resistance to drought stress than 'Mary'. Results suggested that cycocel treatment can neutralize some negative effects of drought stress in 'Mary' and 'Mission' of olive trees.

In order to investigate the effect of two spermidine concentrations (0.5 and 1 mM) on in vitro gynogenesis of six onion accessions from Khorasan province this research was carried out. Results showed that the highest and lowest percentage of gynogenesis rate was belonged to M2 and M5 media, respectively. The highest (1.41) and lowest (0.33) percentage of gynogenic embryo were belonged to Roshnavand-e- Birjand and Sefid-e- Naishabur accessions, respectively. The highest percentage of plant regeneration was belonged to Roshnavand-e- Birjand accession in M2 medium culture. Ashkhane-e- Bojnourd and Dargaz accessions had the highest and lowest percentage of plant survival rate (81.25 and 49.8, respectively). Therefore, spermidine in two concentrations of 0.5 and 1 µ M, without other plant growth regulators, had no positive effect on onion gynogenesis and should not be used instead of 2,4-D and BA. Combination of spermidine with other plant hormones could induce gynogenesis in onion.

Many factors, particularly the planted cultivar for oil production and climatic conditions, can affect olive oil quality. This research was conducted with 12 olive cultivars in olive research stations with different climatic conditions (Taroum, Roodbar, Gorgan, Kazeron and Sarpolezehab). Fruits with 4-4.5 ripening indices were harvested in each region. Fatty acids composition data were analyzed in a factorial experiment based on complete randomized block design. Results indicated that palmitic acid was significantly higher in warm climates, Kazeron and Sarpolezehab. The cultivar and climate conditins had significant effects on oleic acid content and this fatty acid was higher in Taroum, Roodbar, and Gorgan regions compared with Kazeron and Sarpolezehab. Cv. Amphissis had high Oleic acid content in all conditions. Mean linoleic acid content was observed in warm condition of Sarpolezehab which was higher than mean value in Gorgan, The result indicated that Kronaiki oil exhibited the best fatty acid composition in Taroum, Roodbar and Gorgan regions and Amphissis was the only cultivar suitable for warm climate. 'Shengeh' produced the lowest oil quality with regard to fatty acid composition especially in warm region.

With considering importance of post harvest operation on quality criteria of pot marigold (Calendula offıcinalis L.), the effect of flower nutrient source (organic inputs such as cattle manure (25 t ha-1), municipal waste compost (20 t ha-1), spent mushroom compost (15 t ha-1), vermicompost (15 t ha-1) and control) as well as different drying methods including microwave (300, 600 and 900 W), oven (60, 70 and 80oC) and natural-shade drying in room temperature were investigated on physical and phytochemical characteristics of flowers in a factorial experiment based on completely randomized design with three replications in Research Laboratories ofUniversity College of Agriculture and Natural Resources, University of Tehran and Shahid Beheshti University during 2010 and 2011 growing seasons. Criteria such as drying kinetic, antioxidant activity, total flavonoid content, total phenolic compounds and total carotenoid were evaluated. Results indicated that organic inputs had no significant effects on quality criteria of pot marigold except of total flavonoid content while drying methods significantly affected phytochemical criteria. Application of microwave 300, 600 and 900 W resulted in highest amount of total flavonoid content, total phenolic compounds and antioxidant activity, respectively. However, oven drying caused the lowest amount of phytochemical criteria. Interaction effect of nutrient source and drying method significantly affected antioxidant activity in which the highest amount of antioxidant activity was obtained in combination of vermicompost and microwave 900 W. In addition, application of vermicompost combined with oven drying at 60oC caused the lowest amount of antioxidant activity. Based on results of drying curves trend, drying of flowers by microwave showed a faster drying rate than oven and natural-shade drying in which by increasing microwave power and oven temperature, time of flower drying decreased whereas slope of moisture content reduction curve showed accelerated trend. In general, selection of optimum drying method depends on several factors and also it should be considered based on optimum use of energy and effective cost.

In order to study the effects of CPPU and GA3 on fruit quality and quantity of Sultanina grapes, a factorial experiment in a randomized complete block design was implemented in a commercial vineyard near Bonab city (West Azerbaijan province). The spraying was done at fruit set stage using CPPU and gibberellic acid. According to the results, it was found that these plant growth regulators had a significant effect on the diameter and length of the berry, weight, dry matter and moisture, the red value and shrinkage of the fruit while these treatments did not affect the pH and acidity of the fruit. Also, the interaction between growth regulators showed a significant effect on vitamin C content and berry size. Gibberellic acid reduced the level of brix, dry matter percent and the red color value and Increased berries shrinkage In contrast, treatment with 7.5 mg CPPU Not have adverse effects of gibberellic acid and It seems to be an appropriate treatment to improve fruit quality and quantity of Sultanina grapes in the vineyards of the region and can be suggested for both fresh consumption and raisin production.

Low temperature is one of main factors limiting distribution of woody plants. In order to evaluate the resistance of 4-years old seedlings and adult trees of Maclura pomifera to freezing stress, a factorial experiment was carried out based on completely randomized design with three replications in the faculty of Agriculture, University of Tehran. During 2012-2013 sampling were done from the annual branches and carried out from December to March with 30-days interval. Samples were transferred to the thermogradiant freezer with the six freezing temperature of -5, -10, -15, -20, -25 and -30oC. Then, the resistance to freezing temperatures was measured based on electrolyte leakage, start to growing, relative humidity of branches, contents of proline, protein and soluble carbohydrates. The results showed that with the decrease in freezing temperature, electrolytes leakage was significantly increased in March taken samples in both adult and 4-years old trees; However, they showed high resistance in other months, and there were a significant correlation between electrolyte leakage and viability of samples (r=-0.88**). Maximum and minimum soluble carbohydrates contents were related to December and March, respectively, which have high negative correlation (r=0.98**) with electrolyte leakage during this months. Minimum content of proline in shoots was observed in March, which was correlated to highest electrolyte leakage and minimal re-growth of shoot samples during this month. Since the major freezing damages in Maclura pommifera occur in March, and in temperatures below the -20°C, this species seems to be resistant or relatively resistant to freezing temperatures.

The most important postharvest disorder of cut gerbera is stem bending disorder, which occurs below the capitulum. Stem strength and lignification is one of important phenomenon and causes of gerbera stem bending. Therefore, this experiment was conducted to evaluate the effects of salicylic acid (SA) on phenylalanine ammonia-lyase enzyme activity (PAL), as an important enzyme in phenylpropanoids pathway, consequently lignin formation and stem bending disorder of cut gerberas, with different pulse treatment of SA (0,0.25,0.5,0.75 and 1 mM) on two gerbera cultivars with different stem bending percentages. Based on the results, cultivar, SA and their interaction effects, showed significant effects on ion leakage, stem bending, PAL activity and lignification. The results showed a direct and negative correlation between PAL activity and stem bending. Accordingly, ‘Double dutch’ as a resistant cultivar to stem break showed 2 times higher PAL activity than ‘Ecco’ with high stem bending. SA effect depending on cultivar and concentration, had significant effect on PAL, lignification and stem bending; so that, the highest enzyme activity in ‘Double dutch’ and ‘Ecco’ cultivars was observed at 0.5 and 0.25mM concentrations, respectively. The results showed that, SA in low concentrations with increasing of stem lignification led to decreasing of stem bending disorder in both cultivars.

An experiment was conducted to study the micropropagation of Satureja khuzistanica. The seeds were planted in 1/2MS medium. After germination and growth of plantlets, they were subcultured in fresh medium. Then, they cultured into medium supplemented by different concentrations of BA and Kinetin. Results showed that, the highest proliferation (2.4 shoots) was observed at concentrations of 0.5 mg/l IBA and 3 mg/l BA while the lowest proliferation (1.12 and 1.04 shoots) was produced at concentration of 0.25 mg/l IBA, 1.5 mg/l BA and also 0.5 mg/l Kinetin. The tallest shoots (5.76 cm) were obtained at concentration of 0.5 mg/l IBA and 1.5 mg/l BA whereas the smallest ones (2.44 cm) were observed at concentration of 1 mg/l Kinetin. Lowest percentage of survived plantlets (46.6 %) were observed in the media with IBA at concentration of 0.25 mg/l and BA at concentration of 1.5 mg/l. Quarter salt strength MS basal medium induced rich rooting response (85.2%), when compared with 1/2 salt strength MS (46.66%) and MS (17.6%), media. The highest rooting percentage (64.30%) and number of roots (7.7 and 8. 4) were obtained at 0.25 and 0.50 mg/l IBA, respectively. Overall, media containing 0.25 mg/l IBA plus 3 mg/l BA can be recommended for micropropagation of S. khuzistanica.

In order to study the genetic diversity of grapevine in Mahneshan (Zanjan) an experiment was performed during 2012 and 2013. In different phenological growth stages (bud burst, anthesis and fruit ripening) quantitative and qualitative characteristics of 12 genotypes (Marageh, Shahani, Khalili, Ag-ozom, Germez keshmish, Ag-keshmish, Gara-keshmish, Asghari, Pert-pert, Gezel-ozom and Gandomeh) based on IBPGR descriptor were evaluated. Results showed that all of evaluated genotypes belonged to vinifera (european) group. Among the genotypes, Gezel-ozom and Gandomeh had female flowers (with inverted stamens). This two cultivars are very important in breeding programs. Simple correlation analysis results indicated the existence of significant positive and negative correlations among some characters. Cluster analysis of assessed traits at 10 Euclidean distance separated the genotypes into three groups. Five genotypes (Germez keshmish, Ag-keshmish, Asghari, Pert-pert and Ag-ozom) stood in the first group.In the second and third group (Maragheh, Shahani and Khalili) and (Gezel-ozom, Gandomeh, Gara-keshmish and Sahebi) stood respectively. Also the principal component analysis (PCA) showed that the first two main components explained the 78.32% of total variations.

In order to study the effect of planting density and branch pruning on growth, yield and quality of greenhouse muskmelon, a study has been conducted using a factorial experiment in a completely randomized design with three replications and three factors, including cultivar (Galia-52 and Mirella), branch pruning (1 and 2 branch per plant), and plant density (2, 2.4, 2.8 and 3.6 plants per square meter). Results showed that for both cultivars, the number of fruits per plant were more in two branched plants. Generally Fruits of Galia-52 had better quality than Mirella. Two branched plants had more fruit number per plant (3.15), yield (12.74 Kg/m2), yield per plant (4.79 Kg/P), and internode length. By increasing plant density, yield, plant height and internode length increased, but number of nodes, fruits per plant, single plant yield and single fruit weight decreased. Finally two branch pruning combined with 3.6 P/m2 density was the best treatment for both cultivars by producing high yield (11.6 Kg/m2) and without negative effects on fruit sizeandquality.

Populus euphratica Oliv. is a highly heat, saline and cold tolerant native species, with wide range of ecological habitats and conditions. Seed longevity of P. euphratica is too short to be stored in traditional gene banks. For evaluating preservation of P. euphratica seeds in normal conditions (+22oC) as well as in cryogenic conditions (-196oC), three pre-cryopreservation treatments including PVS2, Desiccation and 30% Glycerol were applied before transferring the seeds into liquid nitrogen (-196oC) for 1 week, 1 month and 1 year. To evaluate the effects of the pre-treatments on seed germination and establishment, a part of the seeds were treated with PVS2, Desiccation and 30%Glycerol and incubated at +22oC, instead of liquid nitrogen (-196oC). The 30%Glycerol and PVS2 pre-treatments dramatically reduced the seed germination from 90% in control seeds to 35.00 and 41.67%. Cryogenic (-196oC) condition reduced seed germination from 90% in control seeds to 26.67% and 28.33. However, Desication showed excellent protection of seeds in cryogenic conditions in seed germination and establishment in lab and greenhouse. Control seed in normal conditions stayed for few months. Germination of cryopreserved seeds for a period of one year did not show significant reduction, compared to those kept for one week or one month at -196oC.

In this research, during three consecutive years (2010-2012), a series of diallel crossing was performed among wild type barberry genotypes and Iranian seedless barberry. Setting of seed and fruit in the crossing have been studied and then seedling survival were evaluated in several cultural systems. Results showed significant effects of pollen sources on setting of fruits, seed and seeded fruits in seedless barberry. Pollens of R2N1 genotypes with 46% fruit set and 2.22% seedset and pollens of R4N1 genotype with 69% fruitset and 20.22% seed set had the lowest and highest rates, respectively. Also, There was significant differences (p<0.01) among genotypes on setting of fruit, seed and seeded fruit when pollinated with seedless barberry pollens. In this study, the efficiency of seedless barberry pollens to set seed in wild type barberries was proved and its male sterility theory was rejected. Evaluation of seedling survival rate showed that planting barberry seeds in spring in Cocopeat mixed with Perlite under mist system could increase dramatically seedling survival rate.

Blackberry diversity is high in Iran due to its wild and natural populations especially in south of Caspian Sea. However it has not been investigated before. The goal of this work was to evaluate some wild populations of black berry in Mazandaran province of Iran. At first, region and then location of blackberries plants identified and the traits of leaf, stem, spin, flower, fruit quantity and quality evaluated based on blackberry descriptor via three replications. Results showed that, there was negative significant correlation between the symptoms of pest and diseases with spin number and direction, cross section of stem and terminal leaflet type. Based on the results, four main factor included spin, fruit quantity, plant growth habit and flowering traits explained more than 95% of observed variance. Spin related traits including spin size and direction, hairiness of shoot, stem cross section and fruit and flower size, explained 50% of total variance. Results of cluster analysis divided genotypes into two groups with 100% difference. The Qaemshahr genotypes distanced from each other and located in separated groups whereas belonged to one region. This indicated the variation in genotypes that is used by blackberry local harvesters. In the second group the genotypes separated from each other based on their geographical origin.