Iranian Journal of Horticultural Science
Year:2017 | Volume:48 | Issue:3 |Papers Count:25

In this study, 21 pomegranate genotypes were collected from Lorestan province, and evaluated using morphological and biochemical characteristics. Results of variance analysis showed statistic significant differences between genotypes, except for percent of skin, pH, and soluble solids traits. The amount of variation in total genotypes, showed the highest coefficient of variation was 50.11, 46.06 and 32.22% for vitamin C, weight of fruit and amount of acid, respectively. Principal components analysis showed that four main factors could have denoted 98.91% of the total variation. Distribution of genotypes using Principal components analysis was performed and plot distribution of genotypes showed that A7 (‘Souze shine Shah Taj Kutah’) genotype had the highest fruit weight, the two main components of the first and second highest coefficient was positive. Traits such as single berry weight, the total weight of the skin, weight of 10 seeds, leaf length to width ratio, the percentage of skin in the first component (PC1) and crown length, acidity, leaf and fruit in the second component (PC2), was grouped respectively. Cluster analysis of genotypes was performed by Ward method and 21 genotypes in Euclidian distance 5 were classified into six clusters that genotypes collected from a region were located in different clusters. In this study, important factors in genotype grouping were weight and figure of fruit. These result obtained due to differences between genotypes in each region and no relation betwen genetic distance with geographical distance was found.

This study aimed to assess the water demand and growth traits of ornamental Gaillardia (Gaillardia grandiflora) and Marguerite (Leucanthemum × superbum) in peat-based substrates with different volume based ratios of field soil (Clay loam) and peat moss (100% peat, 80% peat+20% soil, 60% peat+40% soil, 20% peat+80% soil and 100% soil) in a randomized complete block design with three replications in a greenhouse at the horticulture Department, University of Tehran. Irrigation applied based on plant demand (by weight) up to the end of the experiment, but the evaluation of the harvest took place between two specified intervals. The amount of water consumed, growth characteristics, shoot and root dry weight and root development traits were evaluated. Overall study results showed the root system of Gaillardia was more developed than Marguerite, so it was also more efficient in water uptake. Combining 40-60% (v/v) of peat with field soil resulted in progress of the root system and significantly increased the efficiency of water absorption. Therefore, the combination of at least 20% of peat with field soil is recommended with in the production and cultivation of garden plants (Gaillardia and Marguerite).

Gladiolus is one of the bulbous cut flower with a variation in color, shape and size. Spike length, number of florets per spike, plant height and flowering time are the parameters that determine the quality of this flower. This study was carried out to evaluate the effect of gibberellic acid (0, 50, 100 and 150 ppm) and humic acid (0, 250 and 500 ppm) on quantitative and qualitative characteristics ofGladiolus grandiflorus L. cv. White prosperty. The experiment was laid out in a factorial arrangement based on randomized complete block design with two factors; gibberellic acid and humic acid, with 3 replications. Results showed that application of gibberellic acid at all used concentrations significantly increased plant height, inflorescence length and number of florets per inflorescence, compared to the control as well as reduced the time of flowering. Also, gibberellic acid at 50 ppm increased the number of cormlet per plant, and at 100 and 150 ppm enhanced the number of leaves, corm weight and chlorophyll index. Humic acid had no significant effect on flowering time, while significantly increased plant height, inflorescence length, number of cormlet per plant and cormlet weight at both used concentrations and number of leaves, number of florets per inflorescence and leaf chlorophyll index at 500 ppm compared to control. Finally, application of 100 ppm gibberellic acid and 500 ppm humic acid are suggested to improve growth and inflorescence quality in Gladiolus cv. White prosperty, respectively.

The effect of seasonal changes pattern of internal carbohydrates of trees on flowering, fruit set, and fruit development is an important subject for orchard management and physiology of fruit production. With the aim of alternate bearing control, a research was performed based on RCBD design under dry farming condition at Ramsar on 24 years old of Satsuma mandarin trees. Main purposes of this research were to investigate the partitioning of soluble and insoluble carbohydrates of trees duringon and off years, evaluating the relation between carbohydrate reserves, flowering and fruit set, effect of 2, 4-D foliar application on carbohydrate partitioning, abscission enzymes activity, control of alternate bearing and crop quantity and fruit quality. Results showed that bearing level had a meaningful effect on carbohydrate partitioning and its seasonal fluctuations. Activity of abscission enzymes were affected by crop load as well as exogenous 2, 4-D application. Results also showed that 2, 4-D could regulate alternate bearing of Satsuma mandarin trees and improve fruit weight. Based on obtained information, the leaf starch content at the end of June-drop is a reliable biochemical index for predicting of final individual fruit weight at the same year as well as the flower density in the next year.

The aim of this study was to investige the effect of different media cultures and humic Acid (HA) on some vegetative properties and absorption of Phosphorus (P) and Potassium (K) contents in leaf of orange seedling (Citrus sinensis) cv. Valencia grafted on sour orange (C. aurantium) rootstock. A factorial experiment was carried out based on randomized complete block design with three replications. The first factor was HA concenterations of 0, 2.5, 5 and 7.5 gl-1 and second factor was formed by seven different combinations of media culture including 1- soil, 2- zeolite, 3- leaf mold, 4- soil+ zeolite, 5- soil+ vermicompost 6- Soil+ leaf mold 7- soil+ vermicompost+ zeolite. Results showed that effect of HA, media culture and their interaction on all of the investigated traits of Valencia orange were significant (P<0.01). The highest and the lowest seedling hight (81 and 50 cm) obtained in plants cultured in soil+vermicompost+zeolite and 5 gl-1 HA and in soil and without HA, respectively. The highest number of leaves (97), fresh and dry weight of leaf and root, P and K contents obtained in plants cultured in soil+ vermicompost+ zeolite mixture and 5 gl-1 HA. Therefore, application of 5 to 7.5 gl-1 HA and use of soil+ zeolite+ vermicompost mixture is recommended as media culture in order to improvement of quality and quantity of seedling of Valencia orange.

In addition to storage conditions, pre-harvest factors including nutrition is essential to increase the shelf life. In this experiment the effects of three different levels of iron foliar applications (0, 50 and 100 ppm) and nitrogen (20, 40 and 60 ppm) application in the soil were investigated in apple (Malus domestica cv. Delbar stival). Traits such as quality factors during storage period were measured. The factorial experiment was carried out based on randomized completely block design (RCBD) with three replications. According to the results of this study, iron application increased TSS, dry weight and total phenolic contents. Also, with increasing nitrogen concentration, the antioxidant level was increased. Effect of storage on some para meters such as firmness, dry matter, total phenolic content, vitamin C and total antioxidants was significant, leading to a decline in the quality of the fruits. It can be concluded that, iron application at 100 mg/l per tree was suitable for improving the quality indexes for this cultivar.

In the present study, the effects of different concentrations of benzylamino purine (0, 1, 1.5 and 2 mg l-1) and naphthalene acetic acid (0, 0.25, 0.5 and 1 mg l1-) on direct and indirect bulblet rejected set by user of basal plate explants of four ecotypes of Psersian shallot (Lorestan, Zanjan, Sanandaj and Arak) on MS medium were investigated. The results showed that different hormonal treatments and ecotypes affected the time and percent of bulblet regeneration as well as the number, length and weight of regenerated bulblets. Moreover, direct and indirect regeneration of bulblet were different among the treatments. Application of BAP and NAA accelerated the bulblet regeneration of Persian shallot explants and the highest bulblet regeneration (82.26%) and maximum bulbllets number (14.13) were obtained by 1.5 mg g-1 BAP with 0.5 mg l-1 NAA. The explants of Arak ecotype showed the highest percent of bulblet regeneration (64.61%) and bulblets number (10.33) per each explant. The callus induction was only observed in 2 mg l-1 BAP+1 mg l-1 NAA (75.05%) and 1 mg l-1 BAP+0.5 mg l-1 NAA (23.67%) treatments. The rooting of bulblet in all the studied ecotypes was obtained in hormone-free medium in the shortest time (25 after culture) in comparison with other treatments that was also accompanied with the highest percent of rooting (79.917%). According to the results the culture of Arak ecotype bulbs in medium with 1.5 mg g-1 BAP and 0.5 mg l-1 NAA is advisable for invitro bulblets production of Persian shallot.

Economic importance of Chrysanthemum among the other ornamental species has resulted in performing various investigations in tissue culture optimization of this plant, worldwide. In the current experiment, leaf, petiole, petal and stem TCL explants, fromChrysanthenum morifolium cv. Reagan Elite Salmon were cultured in MS medium supplemented with different combinations and concentrations of NAA, BAP and TDZ. Regeneration percentage, number of regenerated shoots per explants and regeneration type were investigated in each treatment. Results indicated significant superiority of shoot regeneration percentage from petiole explants (80.5 percent), while minimum regeneration was achieved from the petal explants (37.2 percent). Shoot regeneration type from different explants in the treatments containing only BAP, was direct and in the treatments containing TDZ and NAA was indirect. Reactions of the explants to the PGR treatments, considering shoot regeneration percentage and average number of regenerated shoots per explants, were so different. As among the treatments consisting combinations of NAA plus each of the cytokinins, in T12 (4.5 mg/l BAP+1 mg/l NAA), petioles and petals represented maximum shoot regeneration percentage and number, while stem TCLs showed minimum rates of regeneration.

This study was arranged in a completely randomized block design to investigate effects of four levels of calcium nitrate on the nutrition responses and growth characteristics of tomato plants. Treatments included T0: control; T1: recommendations of calcium nitrate by Yara International (Soil application), 50 kg/ha for 8 weeks since the first week of fruit set and a total of 400 kg/ha; T2: calcium nitrate consumption based on soil test results and the requirements of tomatoes: 40 kg/ha in the first week of fruit set and a total of 320 kg/ha; and T3: the same as the previous treatment plus foliar application of calcium nitrate at 0.5%. Results showed that there were significant differences between tomato fruits regarding uptakes of nitrogen, phosphorus, calcium, magnesium, dry matter, vitamin C, nitrate, potassium, and fruit firmness (P<0.05). The maximum values for uptakes of calcium, nitrogen and yield were obtained following T1 treatment (65, 85, and 45% higher than the control value, respectively). Regarding total nitrogen, potassium, and magnesium uptakes, and pH, there were no significant differences between T1, T2, and T3. Accordingly, 400 kg/ha (T1) calcium nitrate is recommended to obtain the best fruit yield and quality.

In order to study the effect of ascorbic acid (AsA) on quantitative and qualitative characteristics of Pelargonium graveolens under iron (Fe) deficiency stress, a pot experiment was carried out. Three levels of Fe (0, 20 and 40 mM) and three levels of AsA (0, 1 and 2 mM) were combined factorially based on a completely randomized design with six replications. Uniform rooted cutting were planted in sand and grown hydroponically. After plant establishment, Fe and AsA treatments were applied through half-Hoagland nutrient solution. Results showed that as Fe in nutrient solution decreased, growth characters i.e. plant height, stem diameter, number and length of axillary shoots and leaf area decreased. Moreover, as Fe in nutrient solution decreased, leaf fresh and dry weight, stem fresh and dry weight, decreased, while, oil content increased. Growth responses to AsA was different in plants grown in nutrient solution with 0 mM Fe compared with those in plants grown in nutrient solution containing 20 mM Fe. Daily application of AsA (especially with 1 mM concentration in nutrient solution) increased biomass and oil content. Oil yield, Chlorophylls and carotenoids contents decreased with decreasing Fe, while, AsA increased them under Fe deficiency. Overall, AsA could improve growth and yield of geranium under 20 mM Fe nutrition, however, it was less effective at 0 mM Fe.

In order to study the effect of organic and chemical fertilizers, a field experiment was carried out by using of split plot based on randomized complete block design with seven treatment and three replications on geranium (Pelargonium graveolens), in Fahlian, Nourabad, Fars province territory. Treatments concluded control (no fertilizer and vermicompost), pure nitrogen (200 kgh-1), vermicompost 4 th-1 with 160 kgh-1 nitrogen, vermicompost 8 th-1 with 120 kgh-1 nitrogen, vermicompost 12 th-1 with 80 kgh-1 nitrogen, vermicompost 16 th-1 with 40 kgh-1 nitrogen and pure vermicompost (20 tonh-1). Traits assessed include: plant height, number of lateral branches, biologic yield, branches yield, essential oil percentage, essential oil yield and harvest time. Results indicated significant effect of fertilizer treatments and harvesting time on all traits except harvest time. The intraction of harvesting time and fertilizer was only significant on biological yield and essential oil yield. The mean comparision showed that all traits were higher in the secend harvest compared to the first one. In two harvests organic fertilizer leading to increase studied traits compared to the control treatment. Application of 20 th-1 vermicompst and after that, treatment of 16 th-1 vermicompost with 40 kgh-1 nitrogen had the highest effect in increasing studied traits.

Incomplete apple fruit skin pigmentation could be one of the main causes of decreasing marketability in red cultivars. In this study, the correlation between total anthocyanin and fruit skin color parameters with mineral nutrient content and ratios in 20 commercial apple orchards growing cv. red delicious was investigated. At each orchard, fruits were harvested at commercial maturity stage and categorized into three groups with 20 fruits, according to dark red, medium and light red color. Fruit peel colors parameters such as hue (°h), lightness (L*), chroma (C), green-red (a*), blue-yellow (b*) and total anthocyanin, and nitrogen, phosphorous, potassium, calcium and magnesium contents and mineral nutrient ratios were measured. Results showed that there were a negative correlation between anthocyanin with L*, h°, b* and C* and a positive correlation with a*. Furthermore, a negative significant correlation was found between fruit nitrogen content with anthocyanin and a* and a positive significant correlation with L* and h°. A negative correlation was observed between fruit calcium content with L* and magnesium content with anthocyanin. Furthermore, a positive significant correlation was found between N+K/Ca with L*, h° and b*, but a negative correlation between Mg/Ca with total anthocyanin and a* and a positive significant correlation with L*, h° and b* value. There was a negative significant correlation between N/Ca with anthocyanin and a* and a positive correlation was observed with L*, h° and b* value. Overall, results showed besides climate condition, optimum tree fertilization especially nitrogen and calcium can be important on apple fruit cv. Red Delicious pigmentation.

Today, the use of chitosan as one of plant hormones to increase plant resistance to stresses such as drought has been increased. In order to evaluate the effect of different levels of chitosan on antioxidant enzyme activities in Ajwain under drought stress, the experiment was conducted as split plot based on randomized complete block design with Three replications in research farm of Zabol University in 2014. Drought as the main factor in three levels A1) 50 mm evaporation (control), A2) 100 mm evaporation (medium stress) and A3) 150 mm evaporation (severe stress) of pan evaporation class A and different levels of chitosan spray (control, 0.1, 0.5, 1, 2 g/L) were considered as Sub factor. In this study, by increasing period between two irrigations, the activities of Catalase, Peroxidase, Ascorbate Peroxidase, Gayacolperoxidase, and polyphenoixidase enzymes were increased. There was no significant difference between control and moderate stress for most parameters but maximum activities of Antioxidant Enzymes were observed in severe stress. Using different levels of chitosan caused to improve the activity of antioxidant enzymes, so that, the interaction effect of 0.5 g/l chitosan and drought stress had increased most parameters significantly than that for control.

Increasing of visual quality and nutraceutical properties of fruits plays an important role in fruit marketability and economic incomes of gardeners. Silicon and calcium can play an important role in fruits quality improvement. This study was conducted to evaluate the effect of foliar application with calcium silicate (0, 50, 100 and 200 mg/L) on some fruit quantitative and qualitative characteristics, total antioxidant and calcium content of two strawberry cultivars (‘Camarosa’ and ‘Selva’). The experiment was performed in a factorial based on randomized complete block design with 5 replications. Results showed that fruit length, fruit length to width ratio, fruit fresh and dry weight, vitamin C content in ‘Camarosa’ fruits were more than ‘Selva’ fruits, whereas fruit firmness, TA, TSS, total phenolic, antioxidant content, amount of calcium and catalase enzyme activity of ‘Selva’ fruits were significantly more than the ‘Camarosa’. With application of calcium silicate, fruit length, fruit fresh and dry weight, fruit firmness, the amount of vitamin C, TA, TSS, total phenolic, antioxidant, calcium content and catalase enzyme activity were increased. According to the results, foliar application of calcium silicate at 200 mg/L had the highest effect on improvement of quantitative and qualitative traits of strawberry fruits.

In this study, we evaluated the effects of five levels of potassium phosphite (KH2PO3) on Induced Systemic Resistance (ISR), and also defense related enzymes and metabolites activities during different days in cucumber plants inoculated with Fusarium oxysporum. The experiment was designed as a split-plot in time based on a completely randomized design with three replications. The activity of defense-related enzymes including, catalase (CAT), guaiacol peroxidase (GPX), superoxide dismutase (SOD) and also the accumulation of secondary metabolites such as lipid peroxidation (MDA) and hydrogen peroxide (H2O2), were evaluated in a period of 11 days after pathogen inoculation. Results revealed that defense enzymes activities and metabolites accumulations were significantly increased in plants treated with potassium phosphite in comparison to control. The highest concentration of CAT enzyme (18.7 U mg-1 protein) was measured in plants treated with 4 gr l-1 potassium phosphite (KPhi4) and 5 days after inoculation, that showed 2.81 fold increase in comparison with control (no inoculate with the pathogen). Also the highest concentration of enzymes GPX (233 U mg-1 protein) and SOD (10.8 U mg-1 protein) were recorded at 3 days after inoculation in plants treated with KPhi4 in comparison with control plants. Results showed that accumulation of H2O2 in plant tissues and it's time was in accordance with increasing of defense enzymes CAT, GPX and SOD and it would indicate that the H2O2 production is the prerequisite for production of defense-related enzymes. It was also revealed that MDA accumulation in KPhi4 treatment was less than other treatments, indicating reduced tissue damage and alleviated disease symptoms.

Ziziphora persicaor Iranian kakooti is an annual aromatic plant from Labiatea family that grows wild in Iran and has strong antimicrobial effects. In this research, the aerial parts of this plant were collected at full flowering stage from six habitats. After confirmation of scientific names of the plants by Herbarium of Research Institute of Forests and Rangelands (TARI), the plant materials were dried at shade. The essential oils were obtained by hydro-distillation, the yields were calculated based on dry weight and the oils were analyzed by GC and GC/MS. Results showed that oil yields varied from 0.11% (Meshkin Shahr, Nodooz) to 0.39% (Alamoot, Ghazvine) for different samples. Seventeen to twenty-six components were identified in the essential oils. The main compound in the essential oil of Alamout and Gharetape samples were spathulenol (25.7% and 24.1%, respectively). The major compound in the oil of Urmieh sample was beta-bisabolene (28.8%). The main compound in others oils was epi-alpha-muurolol that its percentage in the oil of Meshkinshahr sample (20.8%) was higher than Gharechaman (17.1%) and Miyaneh (14.4%). Of course the three above components were found in all oils, but their percentages were completely different. Results of this research showed the oil of Ziziphora persica in Iran is completely different with other species of Ziziphora that contain pulegone as main compound in their oils.

Onion is one of the vegetables greatly consumed in the food chain of people and researchers are always trying to improve itsnutritional quality. This study was conducted to investigate the effect of different levels of sulfur (32, 64 and 128 mg L-1 sulfate) and selenium (0, 1 and 2 mg L-1 selenate) on the growth and antioxidant properties of red onion cv. Azarshahr. The study was performed under hydroponic conditions. Results showed that the concentrations of sulfate and selenate and the interaction of them had a significant effect on the most of growth characteristics of onion plants. The highest fresh weight and diameter of bulb (35.70 g and 38.24 mm) was observed in 128 mg L-1 sulfur in combination with 2 mg L-1 selenate. There was a positive correlation between selenate and sulfate with the bulb fresh weight and diameter of onion. The highest percentage of bulb dry matter content (16%) was obtained in 64 mg L-1 sulfate combined with 1 mg L-1 selenate. At all concentrations of sulfate, the plant height was reduced by increasing of selenate. In addition, selenium accumulation was increased in the onion by increasing selenate concentrations in all levels of sulfate. By increasing selenium, antioxidant activity and phenol and flavonoid contents of bulb tissue was increased.

In recent years, demand for organic products because of their high nutritional value and healthier is rapidly increasing. In this research, the effects of organic, integrated and conventional garden management systems investigated on storage life and postharvest quality of pomegranate fruit cv. Rabbab -e-Shiraz at 5oC for 90 days. Characteristics such as weight loss, quality and biochemical parameters were analyzed at harvest, 45 and 90 days after storage. Results showed that the weight loss in organic fruits were significantly lower than conventional and integrated management system during storage. Total soluble solids (TSS) and titratable acidity (TA) content in fruits of conventional management system was higher and ratio of TSS/TA was lower than organic fruits. The highest TSS/TA ratio of pomegranate fruits was obtained from integrated management system. While, total phenolics and flavonoids content of organic fruits were higher at harvest and during storage, they were decreased in all fruits during storage time. Also, total anthocyanin content and antioxidant activity was higher in organic fruits, but contrary to phenolic compounds, anthocyanins content increased during storage. Overall, organic fruits showed higher nutritional value and more storage life.

Olive mill solid waste is enriched from organic matter and mineral nutrient elements, which can be used after compostation for inproving soil fertility and solve its disposal problem. For this purpose, a factorial experiment was carried out during 2013 to 2015 in Manjil region. The treaments were different levels of composted olive mill solid (12, 24 and 36 kg per tree and followed by 15 kg per tree rotted sheep manure as a control) which used on two oilve cvs Zard and Roughany. The results showed that there was no significant difference for oil percent between control and different level of compost after first year, but on the second year, olive tree treated with 36 kg compost showed significantly 5.71 oil percent more than other treatments. There was no significant difference between different leveles of compost and control for oil free fatty acids and absorption in the ultraviolet wavelengths (K232 and K270) over two years. In the second year, the trees that had been treated by 24 and 36 kg of compost, had a better oil quality form which peroxide value was less as compered to other treatmentes. On the second year, oil quality from which flavonoid content in olive tree treated with compost was significantly better than control. However, on this year, oil chlorophyll and carotenoid content of coltrol was higher than compost treated tree, but no significant differenec was found between compost treated trees and control for the ratio of oil chlorophyll to carotenoids content. There was a significant difference between two olive cultivars, Roughani and Zard for oil free fatty acid, peroxide value, K232 and K270, phenols, flavonoids, chlorophyll carotenoids. Overall, the oil quality of both olive cultivars which treated with manure and compost was in the range of extra virgin olive oil, based on standards of the International Council of Olive Oil at two years.

For precise evaluation of the sensitivity of some apple rootstocks to iron stress, an study with a factoreal approach was established based on a complete randomized design with 18 treatments and three replications. Experimental treatments included rootstocks in 6 levels (M9, M26, M7, M25, MM106, MM111) and iron was chosen in three levels (Half strength Hoagland solution as control, Half strength Hoagland without iron, Half strength Hoagland with Bicarbonate). Apple rootstocks were planted in 20 liter pots containing Perlite. Before beginning the experiment, the pots were supplied with half strength Hoagland solution for 2.5 months. After this period, the abovementioned treatments were applied on the rootstocks. Drainage pH was measured 5 times during the experiment. Root ferric chelate reductase activity (FCR) in separated roots and in the intact plant with connected roots was calculated. Then, plants were separated into shoots and roots in the laboratory. Ferric chelate reductase activity, shoot growth, dry and fresh weight of leaf and root, swelling of root tip, leaf chlorophyll (Chl) concentration and iron concentration of leaf and root were also measured. According to the achieved results, M9, M7 and M25 rootstocks in comparison with M26, MM106 and MM111, showed lower leaf chlorosis. Root Ferric chelate reductase activity for M9, M7 and M25 rootstocks treated with 2mM Fe was higher than other rootstocks. The rootstock M9 in this treatment increased 4.3 times in comparison to the control and the MM106 rootstock in 10 mM sodium bicarbonate treatment had the lowest FCR activity compared to the control. In addition to the FCR increase in M9, M7 and M25 rootstocks, they had more effect in the rhizosphere pH decrease than other rootstocks. Biomass indicator (root/shoot dry weight) in rootstocks of M9, M7 and M25 showed larger values. According to the result of this experiment, due to meaningful correlation between the measurement method of FCR with excised roots and chlorophyll index, this method is a suitable approach for screening of apple rootstocks with iron chlorosis in comparison with FCR measurement with intact plant.

Low temperatures lead to numerous physiological disturbances in the cells of chilling-sensitive plants, resulted in chilling injuries and death of tropical and subtropical plants such as tomatoes. In this study, the possibility of cold stress tolerance enhancement of tomato seedlings by imposing drought stress with 10 or 20 percent of polyethylene glycol (PEG) for 10 days was investigated in the greenhouse of agricultural faculty of Bu-Ali Sina University, Hamedan, Iran. The layout was factorial experiment in CRD design with four replications. After drought pretreatment, the seedlings were subjected to chilling 6 h/day at 3°C for 6 days. Drought pretreatment improved growth rate of tomato seedlings subjected to chilling stress as well as RWC, phenol, chlorophyll content and chlorophyll fluorescence ratio (Fv/Fm) when compared with the controls un-chilled seedlings. Interaction effects showed that highest value of root (2.25 g) and shoot fresh (4.4 g) weight, RWC (88.31 %), Fv/Fm (0.834) and total chlorophyll (1.62 mg/g F.W) were obtained in 0 % PEG under the chilling control. In contrast, the highest amounts of MDA (1.46 mm/g F.W) and phenol (10.86 mg/g F.W) content were obtained from 20% PEG and non-chilling stress. In general, results indicated that drought pretreatment could be used effectively to protect tomato seedlings from damaging effects of low temperatures stress at the early stages of growth.

One of the effects of climate change and global warming, on leafy vegetables production, is bolting. The four parental lines derived from Iranian lettuce landrace of Shirazi, Zeareei and Siah with difference in flowering time crosses between each pair and F1, F2, BC1p1 and BC1p2 generations were obtained. Transplants were planted in two separate experiments in a randomized complete block design with three replications and flowering time, head weight, number of leaves and leaf length of biggest outer leaf were recorded. Generation mean analysis showed that in all traits additive dominant model was inadequate and other factors such as epistasis is effective in controlling interested traits. The effect of additive is significant but the effect of dominance is much greater than it. The additive × additive effects and dominance× dominance effects on traits have been effective. To determine the number of effect factors at the flowering time of the F2 segregation and two genes involved in controlling flowering time were confirmed. Results showed that late flowering lines of the Siah and Zeareei landrace produced better quality and quantity head than early flowering lines of Shirazi landrace. Thus flowering time, leaf number and head weight had positive correlation. It is expected that selected genotypes with late flowering time had good potential for this important traits and should be used in breeding programs.

This study was performed for evaluation and comparison of 20 hawthorn genotypes from four different species, to introduce superior genotypes in terms of pomology in West Azerbaijan Province. The different treats such as weight, length and width of fruit, peduncle length, length and width of leaf, petiole length, weight, length and width of seed, fruit firmness and fruit color parameters were measured. The largest fruit was observed in Crataegus azarolus species whereas, the smallest fruit was observed in C. monogyna and C. aplosangouainea species. Leaf length and Leaf width had significant correlation with fruit weight, fruit size, seed length and seed width. The five main factors based on factor analysis were explained approximately 89.11 percent of the total variance. According to cluster analysis based on Ward's method, genotypes were divided into three main groups. Genotypes related to C. azarolus var azarolus and several genotypes related to C. aplosangouainea located in group A which had the highest fruit firmness and seed number. In the second group, the genotypes belonging to C. azarolus were located and these genotypes had the highest fruit length, fruit width and fruit weight. In the third group, the genotypes belonging to C. monogyna and several genotypes related to C. aplosangouainea were located and the fruit density, leaf length and a* color index had a significant role in the separation of this group. Results showed that grouping followed species distribution pattern of genotypes. Results obtained might be helpful for breeding programs and introducing of cultivar in hawthorn.

Grape production with high quality, firm texture and suitable shelf life of the fruit is very important. The purpose of this study, the effect of foliar application of different concentrations (0, 1000 and 2000 mg/liter) of potassium sulfate, potassium nano chelated fertilizer and humic acid on the pigments and antioxidant activity in grape variety ' Bidaneh Sefid' were studied in order to improve the quality of grapes in a completely randomized design in a commercial orchard during 2013-2015. Foliar applications were employed three times, including one before flowering, at fruit set, two weeks after fruit set and one month after the second stage was carried out. Based on the results, potassium sulfate at a concentration of 2000 mg /liter increased the potassium concentrations of leaves, potassium nano chelated fertilizer at a concentration of 1000 mg/liter increased chlorophyll in leaves, anthocyanins in leaf and humic acid with a concentration of 1000 mg /liter increased the phenol concentration, and flavonoid in leaf compared to control. potassium nano chelated fertilizer at a concentration of 1000 mg/liter increased anthocyanins in fruit and superoxide dismutase and also, treatment of potassium nano chelated fertilizer at a concentration of 2000 mg/liter increased the potassium and activity of the enzyme ascorbate, potassium sulfate. Concentration of 1000 mg /liter potassium nano increased the phenol concentrations in fruit, protein and catalase activity. Humic acid at concentration of 1000 mg /liter increased the phenol concentration in leaf, flavonoids in fruit and peroxidase activity compared to control. Results of this study, confirmed a significant effect of treatments, especially potassium nano chelated fertilizer and potassium sulfate at a concentration of 1000 mg/liter on increased enzyme activity. As a result, it strengthens membranes and tissues and thus increased the quality of the fruit.

Carnation is one of the most important cut flowers in the world. The flower is to reduce the economic value due to its short vase life. Some materials can be used to help increase the vase life of cut flowers. According to this, using salicylic acid hormone and plant extracts treatment increased the shelf life of cut flowers. Factorial experiment based on a completely randomized design was conducted with 10 treatments (Different concentrations of salicylic acid, Savory and hemp extracts) and four replications with two varieties of miniature carnation. Factors such as vase life, antioxidant enzymes catalase and the relative gene expression ACC oxidase (ACO) were evaluated. Results showed that the interaction of treatments and cultivars was effective in vase life. Spectro cultivar vase life was more than a pretty tessino cultivar. Salicylic acid at 150ppm increased vase life and catalase activity. In addition, this treatment decreased relative ACO gene expression more than the other treatments and control. Savory and hemp extract treatments at high concentrations increased vase life as well as catalase activity, but ACO expression decreased. So it seems that the use of these treatments can be complementary or good alternative to other chemical treatments.