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Horticultural Science and Technology - Volume:3 Issue: 2, Autumn 2016

International Journal of Horticultural Science and Technology
Volume:3 Issue: 2, Autumn 2016

  • تاریخ انتشار: 1395/09/11
  • تعداد عناوین: 14
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  • Li Tao, Zhang Yu-Qi, Zhang Yi, Cheng Rui-Feng, Yang Qi-Chang* Pages 99-111
    Chinese solar greenhouse (CSG) is universally applied in northern China for producing horticultural products. CSG is characterized by the unbalanced structures with an arched front roof face to the south side and a thick wall as well as back roof in the north side. Such structures affect light distribution in the greenhouse. This study aims to investigate the light distribution properties in CSG from north to south sections, and to investigate tomato plant growth performance in the corresponding locations. Experiments were carried out in a CSG which was divided into three equal sections from north to south side. Tomato was grown in the greenhouse. Results showed that PAR intensity in the south and middle sections of CSG was permanently higher than the north section. This resulted in a distinct plant growth performance in CSG. Specifically, plants grown in the north section of CSG exhibited a shade avoidance response with stem elongation phenotype and leaf expansion. Furthermore, the north-plants showed lower leaf photosynthetic capacity which correlated with a lower total nitrogen and chlorophyll contents in comparison with the plants grown in the middle and south sections. Taken together, plants in the north section of CSG produced less total biomass than the middle and south section plants. We conclude that plant growth is not uniform in CSG due to heterogeneous light distribution which was caused by unbalanced greenhouse structures. This study may provide sound evidence for exploring a proper lighting strategy as well as fine crop management in CSG.
    Keywords: Chinese solar greenhouse, light distribution, plant growth, tomato, Solanum lycopersicum
  • Hamid-Reza Fallahi *, Morteza Ghorbany, Alireza Samadzadeh, Mahsa Aghhavani-Shajari, Amir-Hassan Asadian Pages 113-128
    In this study effect of irrigation managements including irrigation after 100 and 200 mm pan evaporation as normal and deficit irrigation respectively was investigated in Roselle plants. Effects of humic acid (including 0 and 4 kg ha-1) and mycorrhizal inoculants (including Glomus versiforme (GV) and Rhizophagus irregularis (RI)) were also studied on growth, yield and mycorrhizal symbiosis index of Roselle plants. Drought stress reduced the amounts of morphological indices and yield components, while mycorrhizal treatment particularly RI inoculation and to a lower extent humic acid application reduced the negative impacts of water deficit on growth and yield of Roselle plants. Both inoculants of mycorrhizal fungi increased the economical yield of Roselle under drought stress condition, where the amount of calyx yield for RI, GV and control in 200 mm pan-evaporation treatment was 130, 127 and 66 kg ha-1, respectively. In addition, the highest root mycorrhizal frequency was obtained at normal irrigation × humic application × RI (95%) and the lowest value was observed at deficit irrigation × no-humic × no-mycorrhizal inoculation (31.6%) treatment. In conclusion, combined effects of experimental factors showed that seed inoculation of plants by mycorrhiza and to some extent application of humic acid are two reliable strategies for Roselle production under deficit irrigation.
    Keywords: calyx, drought stress, Glomus versiforme, medicinal plants, Rhizophagus irregularis
  • Dennis Maina Gatahi *, Harrison Njuma Wanyika, Agnes Kavoo, Agnes Kihurani, Elijah Miinda Ateka Pages 129-144
    Biological control agents are useful components in the enhancement of plant disease resistance and improvement of soil properties. Effect of biological control agents (BCAs) as a disease control method in plants is hampered by their vulnerability to environmental and edaphic conditions. This study entailed the use of chitosan-silica nanocomposites for delivery of BCAs. Effect of BCAs-nanocomposite complexes (bionanocomposites) on resistance of tomato plants to bacterial wilt, mycorrhizal root colonization and rhizosphere soil properties were investigated. Replacement of mesoporous silica nanoparticles (MSN) in the nanocomposite with nano synthesized clay was also assessed on disease resistance. Tomato seeds and seedlings were pre-treated using bionanocomposites and then inoculated by Ralstonia solanacearum isolated from infected tomato plants in a greenhouse. Bionanocomposites treatment of tomato plants caused a significant increase (P≤0.05) in the level of pathogenesis-related biochemicals such as chitinase and glucanase. Furthermore, beneficial microbial colonization was significantly (P≤0.05) induced in roots treated with the bionanocomposites. Wilting incidence and symptoms were reduced by over 50% when bionanocomposites were used. There was no significant effect (P≤0.05) on induced host plant resistance when mesoporous silica nanoparticles (MSN) were substituted with nanoclay particles. Therefore, due to ease of availability with no significant (P≤0.05) difference in efficacy between the nanoparticles, replacement of MSN with nanoclay in synthesis of the bionanocomposites is recommended. We argue that substitution of nanoclay with MSN makes the process of synthesizing the bionanocomposites sustainable.
    Keywords: AMF colonization, host plant resistance, mycorrhiza-helper micro-organisms, nanoclay, resistance elicitors
  • Majid Rahemi *, Fateme Yazdani, Sahar Sedaghat Pages 145-153
    Selection of frost tolerant cultivars and understanding the mechanisms of frost hardiness could help to improve freezing resistance in olive plants. Olive cultivars may differ in frost hardiness due to differential survival of specific organs. The aim of this study was to screen different olive cultivars based on their stomatal density and metabolic modifications under cold conditions. The ‘Zard’ cultivar had the lowest while ‘Derak’ had the highest stomatal density, respectively. In another experiment, where entire potted olive plants were subjected to freezing stress (0, -6, -12 and -18 ˚C), ‘Zard’ and ‘Dehghan’ were found to be the most tolerant cultivars. They showed the lowest starch content, ionic leakage and wood injury. They also had the highest reducing sugar, phenolic and proline contents among studied cultivars. We concluded that ‘Zard’ and ‘Dehghan’ are the most tolerant cultivars and ‘Derak’, ‘Dakal’ and ‘Shiraz’ are the most sensitive cultivars to freezing injury.
    Keywords: hardiness, ion leakage, proline, wood injury
  • Nafiseh Geshnizjani *, Morteza Khosh-Khui Pages 155-166
    Commercially available amino acids mixtures have several advantages such as enhancing assimilation of fertilizer, facilitating uptake of water and nutrients and improving photosynthesis of plants. To investigate the response of gerbera (Gerbera jamesonni L.) flowers ‘Saltino’ to foliar application of a mixture of 19 essential amino acids (0.25, 0.50 and 0.75 mg L-1) and ammonium nitrate (200 mg L-1) as nitrogen source, a pot experiment was carried out in the research greenhouse of Eram Botanical Garden of Shiraz University. Number of flowers, flower diameter, stems length, chlorophyll, proline, protein and nitrogen contents, photosynthesis rate, stomatal conductance, and vase life of flowers were significantly improved by amino acids treatments. No significant difference was observed between ammonium nitrate and amino acids mixture for flower fresh and dry weights. Results suggested that application of amino acids mixture can induce acetyl CoA, which plays an improvingrole in physiological processes in plants. Application of amino acids mixture as a promising and sustainable approach can be recommended to promote quality and quantity of gerbera flowers.
    Keywords: amino acid, ammonium nitrate, gerbera, morphological, physiological, vase life
  • Mina Farsi *, Mohammad Reza Fatahimoghadam Pages 167-177
    Compared to other techniques of propagation, grafting is the most successful and feasible technique for asexual propagation of walnut plants. There is little information about graft union formation in walnut. Therefore, the objective of this study was to evaluate histological events during graft union formation in Juglans regia L. cv. Chandler scions when minigrafted on the one-year-old seedlings. Cross and longitudinal sections of the graft union were taken for examining different stages of grafting process after 1, 14, 30, 60, 120, 180, 420 and 540 days of minigrafting. One day after grafting, brown necrotic layers were observed at the cut edges. The first callus cells were initiated from cambium layer of rootstock 14 days after grafting but there was weak connection between two parts. New vascular connections between rootstock and scion were observed 30 days after grafting . Vascular connections were increased in central parts of the graft union 60 days after grafting. In mid-summer (180 days after grafting), necrotic layer was almost disappeared in the central longitudinal sections but they were increased especially in the bark, callus and top parts of the graft union due to high temperature and low humidity. In 420 days after grafting, two parts were strongly connected by xylem vessels, but necrotic layer was still remained and observed in some parts. In 540 day after grafting which was coincided with the end of second growing season, two parts were tightly connected to each other and necrotic layer disappeared in most of cross and longitudinal sections.
    Keywords: callus, graft union, rootstock, scion, vascular connection, walnut
  • Negin Akhlaghi Amiri *, Ali Asadi Kangarshahi, Kazem Arzani, Mohsen Barzegar Pages 179-186
    Summer fruit drop (June drop) is one of the main reasons for low yield in some citrus varieties in northern Iran. Recognition of physiological changes in fruit abscission zone (calyx) and application of suitable treatments would reduce or control abscission. Hence, the changes of auxin, cellulose, and polygalacturonase in calyx of Thomson navel fruitlets were measured and their relations with abscission and mineral nutrition of fruitlets as well as the effect of different treatments on them at June drop were evaluated. A randomized complete block design (RCBD) experiment was performed with 8 treatments and 4 replicates. Treatments were as follows: 1. control; 2. urea (1%); 3. urea 2,4-D (15 mg l-1); 4.urea GA3 (15 mg l-1); 5.urea sucrose (1%); 6.urea ZnSO4 (0.5%); 7. urea ZnSO4 2,4-D; and 8. urea ZnSO4 GA3. Results showed that abscission had a significant negative correlation with auxin and a significant positive correlation with cellulase and polygalacturonase of the calyx. The control group had the lowest auxin and the highest cellulase in calyx. Maximum effect (Approximately 24% reduction in abscission) was obtained after foliar application of urea sucrose (treatments 5). The use of urea alone or in combination with 2, 4-D and GA3 had no effect on abscission; however, using it in combination with sucrose was the most efficient treatment in this experiment. Furthermore, the combination of urea and Zn provided an effective treatment. A majority of micronutrients (Mg, Fe, Mn, Zn, Cu and B) had a positive correlation with auxin and a negative correlation with enzymes. Therefore, nutritional management and providing an appropriate condition to maximize photosynthesis can balance physiological metabolism and reduce fruitlets abscission.
    Keywords: Abscission, Auxin, Citrus, Enzyme activity, Nutrition
  • Taher Barzegar *, Pouria Moradi, Jaefar Nikbakht, Zahra Ghahremani Pages 187-197
    To investigate effects of putrescine (Put) and humic acid (HA) on fruit yield and physiological attributes of okra (Abelmoschus esculentus L. 'Kano') under water deficit stress, a field experiment was conducted in split plot based on a randomized complete block design with three replications. Plants were exposed to three different irrigation regimes (33%, 66% and 100% ETc) and were treated with foliar application of Put (0, 0.5, 1 and 1.5 mM) and HA (0, 150 and 300 mg l-1). The results showed that deficit irrigation significantly decreased fruit yield, relative water content (RWC), vitamin C and water use efficiency (WUE), whereas proline content and catalase and peroxidase activities were increased. Foliar application of HA and Put significantly increased fruit yield, RWC, vitamin C and proline contents, catalase and peroxidase activities and WUE. The results suggested that HA at 300 mg l-1 and Put at 1.5 mM can improve growth, yield and quality of okra fruits.
    Keywords: antioxidant enzyme activity, fruit yield, proline, vitamin C, water use efficiency
  • Abdolhossein Aboutalebi Jahromi *, Mehdi Hosseini Farahi Pages 199-209
    Marigold has special importance and application in landscape designing. Nowadays, various species and cultivars of this plant are grown in many climates, where different environmental stresses such as freezing, salinity and drought can lead to vegetative disorders. This study was carried out to investigate the interactions between salinity and ammonium nitrate on seed germination, vegetative growth and sodium and potassium concentrations in French marigold flowers (Tegeta patula). The experiment was conducted as a factorial arrangement based on a completely randomized design with two factors: salinity (0, 2, 4, 6 and 8 mmos cm-1) and ammonium nitrate (0, 15 and 30 g l-1) with four replications. Based on the obtained results, different salinity concentrations were negatively influenced all studied parameters except germination rate. The application of ammonium nitrate recovered the studied parameters to the same level as the control plants. Plant height was decreased by increasing salinity concentrations. The tallest plant was observed in the control treatments. Salinity levels negatively influenced shoot fresh weight. Different levels of ammonium nitrate had significant effects on root dry weight and potassium and sodium contents. Ammonium nitrate led to reductions in root dry weight and potassium content, and an enhancement in sodium content in the shoot. Sodium and potassium levels were increased and root dry weight was decreased by increasing salinity. Enhancement of potassium ions in the marigold following salinity stress can improve its tolerance to salinity stress.
    Keywords: ammonium nitrate, elements, marigold, salinity, vegetative growth
  • Fatemeh Ranjbari, Farid Moradinezhad *, Mehdi Khayyat Pages 211-219
    Pomegranate is a subtropical fruit that is widely consumed as fresh fruit and juice, however, its postharvest life is limited mainly due to storage disorders. The aim of this study was to determine the effect of nitric oxide (NO) on antioxidant activity and quality attributes of pomegranate fruit. The fruits were dipped for two minutes into different NO concentrations (0, 30, 100, 300 or 1000 µM). Then, the fruits were stored in cold room at 5 °C and RH 85%. After 90 days storage, changes in chilling injury, electrolyte leakage, titratable acidity (TA), total soluble solids (TSS), pH, antioxidant activity and total anthocyanin were evaluated. The results showed that 1000 µM NO application resulted in significant decrease in electrolyte leakage and TSS and maintained antioxidant activity and total anthocyanin in pomegranate fruit. However, no significant effect of NO treatment was observed on TA and chilling injury index. In conclusion, postharvest application of NO may be a promising method for maintaining quality of pomegranate fruit during cold storage.
    Keywords: chilling injury, Color, pomegranate, postharvest physiology, sodium nitroprusside
  • Mohammad Aminifard, Hassan Bayat* Pages 221-229
    In this study effect of application of food waste vermicomposts to soil on antioxidant compounds, fruit yield and quality of sweet pepper (Capsicum annum L.) were investigated in field condition. Four vermicompost levels (0, 5, 10 and 15 t/ha) were applied to soil based on a randomized complete block design with three replications. The results showed that the highest (21.87 kg m2)and lowest (14.69 kg m2)fruit yield were achieved in plants treated with 5 t/ha vermicompost and control, respectively.Vermicompost treatments positively influenced fruit antioxidant compounds (antioxidant activity, total phenolic, carbohydrate content and total flavonoid). The highest antioxidant activity (81%) and carbohydrate content were obtained in plants treated with 10 t/ha vermicompost, while their lowest values were recorded in the control plants. Fruit quality indices (pH, titratable acidity, ascorbic acid and fruit firmness) were significantly influenced by vermicompost treatments. However, no significant difference was found for total soluble solids between treatments. There were 40, 61 and 56% increase in the amount of Titratable acidity, ascorbic acid content and fruit firmness following application of vermicompost (15 t/ha) when compared to their values in control, respectively. In conclusion, soil application of vermicompost can positively influence antioxidant compounds, fruit yield and quality of pepper.
    Keywords: ascorbic acid, carbohydrate content, capsicum annum, fruit firmness, vegetable crop
  • Mahmood Izadi *, Ali Reza Shahsavar, Abbas Mirsoleimani Pages 231-242
    The relationships between rooting potential with endogenous phenolic compounds, nitrogen and soluble carbohydrates of cuttings for five olive cultivars (‘Rowghani’, ‘Dusti’, ‘Tokhmekabki’, ‘Konservalia’ and ‘Amigdalolia’) were investigated. Extracts of the leaves and the base of the cuttings were used for analysis of biochemical compounds. Results showed that there were significant differences in rooting potential among olive cultivars. There was no correlation between leaves and stems nitrogen contents and rooting ability of the cuttings. Moreover, leaf and stem soluble sugars, leaf total phenolics, stem caffeic acid, narengin and chlorogenic acid contents of the leaf and stem, did not affect the rooting potential of the cuttings. However, leaf catechin, stem total phenolics and vanillic acid had positive effects on rooting potential of the cuttings. There was a negative correlation between rooting percentage of the cuttings and leaf gallic acid and narengine contents.
    Keywords: biochemical components, leafy cuttings, olive, rooting potential
  • Somaye Amini *, Majid Azizi, Mohammad Reza Joharchi, Farid Moradinezhad Pages 243-253
    This experiment was conducted in Ferdowsi University of Mashhad, in 2011 to investigate the allelopathic potential of 68 medicinal and wild plant species belong to 19 plant families grown in Iran. Results showed that among examined plants, stigma and style of Crocus sativus,leaves of Artemisia kopetdaghensis, Mentha piperita, Zhumeria majdae, Frulago subvelutina, flowers bud of Eugenia caryophyllata, flower of Perovskia abrotanoides, fruits of Melia azedarach and Ruta graveolenhad the strongest inhibitory effects on lettuce seedling growth. Interestingly by using of very low amount of plant samples (10 mg)growth inhibitory effects of these plants were observed by more than 70%. Additionally, the leaf of Atriplex canescens and the flower of Achillea millefolium had the strongest inhibitory effect on radicle growth (more than 75%) compare to the growth of hypocotyl (less than 20%). Here we can suggest that plants with inhibitory effects on growth and development of other plants have the potential to be applied as biological herbicides; this finding can be highlighted as new sustainable herbicides for biological control of weeds.
    Keywords: allelochemicals, biological herbicide, secondary metabolites, weeds
  • Abdolhossein Abootalebi Jahromi *, Hamed Hassanzadeh Khankahdani Pages 255-264
    Effects of humic acid on some vegetative characteristics and mineral concentrations of Mexican lime were investigated under different salinity concentrations. Four doses of humic acid (0, 1500, 3000 and 4000 mg/kg soil) and four salinity levels (1500, 2500, 3500 and 4500 µmos) were applied on Mexican lime seedlings. Experiment was conducted as a factorial arrangement based on a completely randomized design. The results showed that humic acid had a positive influence on plant height under salinity stress. Shoot number was significantly increased by application of humic acid under salinity stress conditions. In 4500 µmos salinity, application of 4500 mg/kg humic acid caused an increase in shoot fresh and dry weights, root dry weight and shoot potassium concentration. Percentage of sodium was decreased by application of 3000 mg/kg humic acid in the shoot of plants that were exposed to 4500 µmos salinity level. humic acid at 1500 mg/kg caused a reduction in shoot sodium percentage under 3500 µmos salinity level. When compared to the non-treated plants, application of humic acid led to a decline in chloride percentage in Mexican lime seedlings. In conclusion, 3000 and 4000 mg/kg humic acid can be used to reduce the toxic effects of salinity and also to decrease the uptake of toxic elements such as sodium and chloride in Mexican lime seedlings.
    Keywords: chloride, potassium, sodium, vegetative traits