Iranian Journal of Horticultural Science
Year:2021 | Volume:52 | Issue:3|Papers Count:20

To study the biochemical parameters of plum cv. Flavor supreme pluot during storage, an experiment was conducted in two separate stages and along with it. The first stage, salicylic acid with concentrations of 0 (Control), 2 and 4 mM, and iron chelate with concentrations of 0 (Control), 0.1 and 1 g.l-1, three times at 30, 60 and 90 days after full bloom on plum cv. flavor supreme pluot was sprayed. The second stage was carried out in a cold storage with two temperatures of 1 and 4 ° C, and then some biochemical traits including antioxidant capacity, ethylene production, weight loss and ion leakage were measured. The results showed that salicylic acid alone had a significant effect on ethylene production and ion leakage at 1 °C at 1% level and at 4 °C only on ion leakage at 1% level. Also, iron spraying had significant effect on ethylene production at 1 °C and on weight loss of both temperatures. The fruits stored at 1 °C showed more storability than 4 °C and after 60 days were marketability.

Chilling injury is the main problem of pomegranate fruit during storage at below 5 °C, which is associated with browning husk, arils pomegranate and loss of its nutritional quality. In this experiment, the effect of intraction between arginine (0, 1 and 2 mM) and methyl jasmonate (0, 0.1 and 0.2 mM) in form of foliar spraying on the tree in three stages of 60, 40 and 20 days before harvest for redducing chilling injury and keeping nutritional quality of pomegranate were evaluated on 0, 30, 60, 90 and 120 days at 4± 0.5 °C during storage. The results showed that combined treatment between arginine (2 mM) and methyl jasmonate (0.1 mM) led to reducing chilling injury (37.74 %), electrolyte leakage (31.42 %) and malondialdehyde accumulation (29.46 %). Also, pomegranate treated with intraction treatment between arginine (2 mM) and methyl jasmonate (0.1 mM) exhibited higher ascorbic acid content, phenylalanine ammonia-lyase, phenols and anthocyanins and lower polyphenol oxidase enzymes activity which ultimately increased the antioxidant capacity of fruits. This treatment increased the enzyme activity of ascorbate peroxidase, catalase and superoxide dismutase by 9.04, 8.18 and 44.21%, respectively, in comparison with the control, leading to reduction the accumulation of hydrogen peroxide in these fruits. Thus, combined treatment between arginine and methyl jasmonate via enhancing antioxidant system, and reducing chilling injury led to enhanced nutritional quality, maintained safe membrane integrity and marketable.

In order to study the effects of spermine in Catharanthus roseus L under salinity stress conditions, a factorial experiment was conducted in a completely randomized design pots containing 4:1 brown peat moss to perlite in greenhouse of Zanjan University. Treatments were four spermine at four levels (0, 5, 10 and 15 ppm) and salinity stresses at three levels (0, 60 and 120 mM) of sodium chloride. Traits which were studied were as fresh and dry weight, plant height, flower diameter, leaf number as morphological traits, relative water content, total chlorophyll, carotenoids as physiological traits, activity of antioxidant enzymes such as peroxidase and proline. Results showed that application of polyamine spermine improves growth and yield of Chatarantus roseus L in stress condition and on fresh and dry weight, plant height, flower number, relative water content, proline, chlorophyll content, carotenoid, peroxidase enzyme and leaf number at 1% and 5% probability levels. The highest proline content (0.37 µmol/g FW) was obtained in 10 ppm and the lowest (0.23 µmol/g FW) in control treatment. The highest peroxidase enzyme (0.099 units. g-1 FW.min-1) was obtained in 15 ppm spermine treatment which showed an increase in spermine compared to the control. Therefore, the use of spermine in this plant for achieving desirable growth indices is recommended and can be beneficial.

Pomegranate (punica granatum L.) is one of the subtropical fruits and sensitive to chilling injury, so preservation of that in cold storage is associated with some limitations. In this study the impacts of Aloe vera gel (0, 40 and 80 %) on chilling injury, nutritional quality and decay of pomegranate fruit, during 90 days at 4 ºC and 85-90 % relative humidity were evaluated. Sampling to determination of intended criteria were done at 30, 60 and 90 days of cold storage. Results showed that Aloe vera gel decreased the chilling injury and decay incidence significantly and the lowest level of chilling injury (11.6 %) and decay incidence (18.66 %) were observed in fruits with 80% of Aloe vera gel treatment after 90 days of storage. Also this treatment controlled well the levels of malondialdehyde (as an indicator of membrane lipids peroxidation), electrolyte leakage, and weight loss. Furthermore, 80% of Aloe vera gel treatment enhanced the antioxidant capacity and the activity of superoxide dismutase, catalase and ascorbate peroxidase and preserved the ascorbic acid content at higher level. High levels of total phenols, flavonoids, and anthocyanins were observed in Aloe vera gel treated pomegranate fruits, as a result of a higher activity of phenylalanine ammonia-lyase and a low activity of polyphenol oxidase. In conclusion, applying of Aloe vera gel in 80 % concentration, as an natural cover, could increase cold stress tolerance and preserve nutritional values of pomegranate fruits during the storage period.

Dill (Anethum graveolens L.) is one of the most important vegetables that has valuable medicinal properties, including anti-flatulence, stomach acid, and difficulty removing. Identification of dill native ecotypes is considered as one of the most important steps in the field of cultivation improvement and breed of this product. In order to evaluate the genetic diversity in different ecotypes of dill based on morphological traits, an experiment was conducted in a randomized complete block design with three replications. Based on the results of analysis of variance, the studied ecotypes were significantly different in most traits. According to the comparison of mean results, the average maximum plant height (80.02 cm), stem length (69.55 cm), stem diameter (2.95 mm), shoot fresh weight (6.36 g) and shoot dry weight (1.78 g) was belonged to Urmia ecotype. The correlation results showed that there was a significant correlation between most of the studied traits. Based on factor analysis, the first factor explained 33.95% of the variance in which most of the vegetative traits included. Based on cluster analysis, 30 ecotypes were divided into four different groups and there were significant differences, especially for the shoot yield between the groups. According to the results of stepwise regression, internode spacing and leaf length were entered into the model. In general, the results of this study showed that dill ecotypes collected from different parts of Iran have a high diversity in most of the studied traits and valuable ecotypes can be found among them.

In the present study, effects of exogenous citrulline (control, 1 mM and 2 mM) and water availability (100% WA, 50% WA and 25% WA) on growth indices, health of photosynthetic system, and essential oils quantity of hyssop were examined in two successive harvests (summer and autumn, 2019). Extraction of essential oils and determination of its content was performed by using clevenger-type apparatus in full blossoming stage. Analysis of variance showed that essential oil content, fresh weight, leaf area, plant height, total chlorophylls, and Fv/Fm indicator were decreased under severe water deficit stress (25% WA). Although citrulline doesn’t have a significant effect on essential oil content, citrulline at 2 mM could increase essential oil content under severe water deficit stress by about 15% and 30% in the first and second harvest, respectively. According to mean comparison, citrulline employment at 2 mM could significantly improve total chlorophyll content, anthocyanines content, relative water content and Fv/Fm indicator under severe water deficit stress. Overall, results of experiment corroborate that citrulline in low concentrations can economically collaborate as a metabolic agent in improving the essential oil content and growth parameters of hyssop.

In order to investigate the effect of superabsorbent and mycorrhizal fungi on reducing water consumption, growth traits and potato yield, an experiment with strip-factorial design was performed. In this study, the amount of irrigation water at three levels (100, 75 and 50% of water requirement based on evapotranspiration) in horizontal plots and the use of Trawat200A super absorbent with two levels (0 and 80 kg / ha) and mycorrhiza on two levels (inoculation and non-inoculation with Glomus etunicatum) were placed in vertical plots. The results of combined analysis of variance showed that effect of irrigation and the use of mycorrhiza and superabsorbent were significant in most vegetative traits as well as yield. Means comparison showed that vegetative traits and total yield decreased by application of low irrigation, but this decrease was significantly less in mycorrhizal inoculation conditions and with the application of superabsorbent polymer. Under moderate and severe stress conditions, the combined use of mycorrhiza and superabsorbent increased the total yield compared to non-consumption (control) by about 9.5% and 10.15%, respectively.

In order to investigate the effect of plant growth promoting rhizo-bacteria (PGPRs) and humic acid on some morphological and physiological characteristics of marshmallow (Altheae officinalis L.) a pot experiment was carried out under greenhouse condition at Faculty of Agriculture, University of Birjand, in 2017. The experiment was conducted using a complete randomized blocks design based on factorial arrangement with three replications. First factor was seed inoculation with strains of Pseudomonas fluorescence bacteria at four levels (non- inoculation, inoculation with strains 51, 79 and 163) and second factor was humic acid at four levels (0, 150, 300 and 450 mg/kg soil). Results showed that Pseudomonas fluorescence strains and humic acid had significant effects on morphological and physiological measured traits. The most effects of inoculation created by strain 163 of Pseudomonas fluorescenss bacteria and it increased leaf dry weight, leaf area, leaf chlorophyll index, carotenoids and protoin leaf compare to control. The result also showed that increasing of humic acid concentration up to 150 mg/kg of soil increased, leaf area, leaf chlorophylls index, chlorophyll fluorescence ­index and protein leaf compare to control. Combination use of Pseudomonas fluorescenss bacteria (strain 163) and humic acid (150 mg/kg soil) had the most effect on increasing of leaf fresh weight, leaf area, chlorophyll a, chlorophyll b, total chlorophyll, carotenoids and phosphor leaf compare to control. Due to these results, application of biological fertilizers containing Pseudomonas fluorescence and humic acid can improve morphological and physiological characteristics of marshmallow.

Drought is one of the most important environmental factors which limit the growth of woody plant. In order to evaluvate the resistance of Caspian locust seedlings to drought stress through inoculation with arbuscular mycorrhiza fungi a factorial experiment was performed in completely randomized design in 2016-2018. The factors were included mycorrhiza at two levels (inoculation and uninoculated with Glomus moseae) and drought stress at two levels (Well-watered and withholding water). Drought stress significantly reduced growth traits such as relative water content, percentage of aerial and root dry biomass, content of total chlorophyll, total carotenoid content and cell membrane stability index and significantly increased proline content. Root inoculation of seedlings with mycorrhizal fungi improved relative water content (14%), total carotenoid content (25%), aerial dry biomass percentage (4.5%), root dry biomass percentage (6.2%), and total antioxidant capacity (54.8%) than to uninoculated seedlings. Also, cell membrane stability index, total chlorophyll content, total phenol content and total flavonoid content in inoculated seedlings were higher than non-inoculated seedlings under both drought and normal irrigation conditions. Overall, the results showed that mycorrhizal fungi improved growth characteristics and reduced adverse effects of drought stress by increasing antioxidant compounds in Caspian locust seedlings.

Salinity stress is one of the most important constraint for yield of medicinal plants. In order to investigation the effects of silicon nanoparticle foliar spraying on growth characteristic, physiological and biochemical parameters of dragonhead (Dracocephalum moldavica L.) under salinity stress condition a factorial experiments based on completely randomized design with three repetitions and each repetition, including two pots in hydroponic conditions was carried out at research greenhouse of Mohaghegh Ardabili University at 2018-2019. Experimental factors consisting salinity stress at four levels (0, 50, 100 and 150 mM of Nacl) and foliar spraying of silicon nanoparticle at three levels (0, 100 and 500 mg/l). Morphological studied traits including plant height, fresh and dry weight of plant, physiological parameters such as chlorophyll, electrolyte leakage, relative water contents and biochemical parameters such as proline and antioxidant enzyme activity were measured. Results indicated that salinity stress significantly decreased morphological traits include plant height, fresh and dry weight of plant and physiological parameters such chlorophyll and relative water content of leaves were reduced, while free proline content of leaves and electrolyte leakage from cell membranes were increased. Foliar spraying of silicon nanoparticle alleviated salinity stress effects on dragonhead plants via increases in growth characteristics and enhancing antioxidant enzyme activity such as ascorbate peroxidase and super oxide desmutase. Five hundreds mg/mL of nanosilicon showed the maximum effect on diminishing negative effects of salt stress on most of the parameters. Therefore, the use of nano-form of silicon element is proposed as alleviator of salt stress in dragonhead.

In order to investigate the effects of water deficit and nitrogen fertilizers on peppermint’s essential oil yield and its compounds, the current experiment was conducted in Research Field of Tarbiat Modares University in 2018, based on split with three replications. The experimental treatments consisted of three irrigation regimes (respectively after depleting 25, 40 and 55% of available water in root growth zone) as the main factor and six fertilizer treatments based on nitrogen requirement as sub-factors. The results showed that the highest essential oil yield was obtained under normal irrigation conditions with urea, while severe water deficit stress caused a reduction of 44% in dry matter and essential oil yield. In this study, 36 compounds were identified in essential oil. The most important components of essential oil were menthol, menthon, menthofuran, piperitone and menthol acetate. Water deficit increased the quality of essential oil (increased menthol and menthon and decreased menthofuran and polygon). In this regard, the use of nitrogen fertilizer increased both the quality and yield of essential oil. In general, it can be concluded that moderate water deficit accompanied with nitrogen fertilizer (urea alone or in combination with vermicompost) might increase the quality of peppermint’s essential oil. Increasing essential oil quality caused by water deficit, reduced quantitative essential oil yield.

In order to investigate amount of deficit irrigation and different levels of water salinity on some morphophysiological traits of parsley, an factorial experiment based on completely block design in three replicates was carried in greenhouse condition. The first factor include irrigation amount at three levels (60, 80 and 100% of field capacity) and the second factor include water salinity at three levels (0.5, 2 and 4 dS/m). Results showed that decreasing irrigation and increasing water salinity cause deacreasing plant height, leaf number per plant, aerial fresh and dry weight, root fresh and dry weight, relative water content and chlorophile content. With increasing salinity to 4 dS/m ion leakage and activity of catalase and ascorbate peroxidase increased and with increasing amount of irrigation these traits reduced significantly.

Orchids are one of the most popular plants in the world. Because of its hard propagation as most important problem, micropropagation technique has been employed recently. In this study, commercial micropropagation of orchid Phalaenopsis cut flower “Detroit” was done by vegetative tissue. First, nodal explants of Phalaenopsis amabilis cv. Detroit flower stalks cultured on Murashige and Skoog (MS) medium supplemented with different concentration of NAA and BAP for direct regeneration and the obtained planlets were cultured on ½ MS medium supplemented with different combination of NAA, IAA and activated charcoal for rooting. The sterile leaves of plantlets were cultured on ½ MS medium containing NAA, BAP and TDZ for evaluation of regeneration and direct production of somatic embryos. Results showed that effective concentration for plantlet regeneration obtained in MS medium containing 1 mg/l NAA and 4 mg/l BAP. The highest number of root produced in 2 mg/l NAA. The highest number of protocorms obtained at 3 mg/l TDZ. The plants survived rates from nodal flower stalk explants was 84.93%. At the end, the highest plantlets acclimatization (90.20 %) was in medium containing cocopeat and activated charcoal (1: 1).

Drought is one of the major factors limiting horticultural products and this is more important in arid and semi-arid regions. Due to the importance of nanotechnology in improving the methods available in horticulture, this experiment was performed on Rosa × damascena Mill as factorial experiment based on the completely randomized design with three replications at Faculty of Agriculture, Ferdowsi University of Mashhad, in the growing season of 2018. The treatments consisted of 2 irrigation regimes (3 days and 6 days) and 5 levels of titanium (0 (control), 15 and 30 ppm titanium dioxide, 15 and 30 ppm nano-titanium dioxide). The results showed that with increasing the irrigation interval, decreased leaf area and flower diameter. Titanium was affected on flower diameter, peduncle diameter and length of peduncle at all levels. Number of flowers increased by 15 and 30 ppm titanium dioxide 40.8 and 54.9%, respectively, and with 15 and 30 ppm nano-titanium dioxide 84 and 69%. In treatment of 30 ppm nano-titanium dioxide and irrigation interval 3 days, the amount of proline was 0.20 and in the same treatment of titanium and irrigation interval 6 days, was equal to 0.50 µmol/g. In general, the use of titanium dioxide and nano titanium dioxide resulted in improved growth traits and flower diameter. Also, among the used levels, 15 ppm nano-titanium dioxide had a greater effect on flower diameter, flower number, relative water content, and spade.

In order to investigate the effect of planting date on local landraces and varieties of Hibiscus sabdariffa L., a factorial experiment was conducted in a randomized complete block design in Dalgan during the 2019. Planting date as the first factor in five levels (March 6, April 4, May 5, June 5 and July 01) and genotypes and cultivars as the second factor in ten levels (Jiroft, Delgan, Bampour, Iranshahr, Nikshahr, South Rudbar, Saravan and Qale Ganj and two commercial varieties HA and HS-24) were considered. The examined traits included stem diameter, fresh and dry boll weight, sepal dry weight, anthocyanin, and etc. Results showed that the effect of planting date on all studied traits was significant at 1% level. The effect of genotype was significant on the number of days to budding, leaf number, days to 50% flowering and sepal dry weight per plant. The interaction of planting date and genotypes on sepal dry weight, anthocyanin content, seed rate and biological yield were significant at 1% level. The highest sepal dry weight per plant was obtained at May 15 planting date. Also, the local landrace of Dalgan and Saravan had the highest and the lowest amount of sepal dry wieght, respectively. Fresh and dry weight of boll, number of leaves, stem diameter, plant seed and anthocyanin content were significantly correlated with sepal dry weight. As a result, May 15 planting date and local landrace of Dalgan showed higher yield.

Present study was done to optimizing the medium culture for rooting the micro cutting of pyrodwarf rootstock under in vitro condition. Propagated shoots of pyrodwarf were used as micro cutting for rooting assay. For rooting, the shoots in 2-3 cm length separately were cultured in MS and ½ MS media cultures with different concentrations of indole butyric acid (IBA: 0, 0.5, 1 and 1.5 mg/l) and putrescine (Put: 0, 25, 50, 75 mg/l). Th mean comparison analaysis showed that in each medium culture the growth regulator IBA and putrescine significantly influenced the rooting and shoot growth. The percent of rooting induction and the length of regenerated roots in ½ MS medium respectively 41.67 and 12.30% were higher than MS medium. The survey effect of IBA and putrescine on rooting of pyrodwarf rootstocks showed that the application of these compounds is necessary for rooting of explants under in vitro condition and the explants in free growth regulators medium did not show any rooting. In both medium (MS and ½ MS) the highest root induction was obtained in 0.5 mg/l IBA and 25 mg/l putrescine. The shoot length of cultured shoots in MS and ½ MS approximately was similar that in combination treatment of IBA and putrescine the longest shoots were observed. According to obtained results, ½ MS medium with 0.5 mg IBA and 25 mg/l putrescine suggested for successful rooting in micro cutting of pyrodwarf rootstock.

Witches’ broom disease of lime (WBDL), caused by ‘Candidatus Phytoplasma aurantifolia’, is major limiting factor for Mexican lime (Citrus aurantifolia Swingle) production in southern Iran. In this investigation, leaf nutrient profiling of the healthy and infected rooted Mexican lime during WBDL progression (90-330 days) as well as to distinguish the infected from the healthy Mexican limes under greenhouse condition. For this aim, the healthy and infected plants were sampled 90, 150, 210, 270 and 330 days after inoculation with phytoplasma and leaf nutrient concentrations including nitrogen, phosphorus, potassium, calcium, magnesium, boron, iron, manganese, zinc and copper were measured during WBDL progression. The results showed phytoplasmal infection mostly caused to a marked decrease in the concentration of nitrogen, calcium, boron, manganese, and significant increase in phosphorus, magnesium, potassium, iron, and zinc in the infected leaves. In Mexican lime leaves, copper concentration did not significantly change after inoculation with phytoplasma with respect to the healthy plants. In addition, the principal components analysis (PCA) based on the concentration of nutrients could not distinction infected and healthy plants in the early stages of sampling (before the appearance of symptoms), but PCA revealed a clear distinction between the leaf nutritional profiles of healthy and infected plants after the appearance of symptoms during the progression of WBDL. In conclusion, this study provides new insights into the lime response to phytoplasma infection during the progression of WBDL and it can be useful in adopting strategies to improve and increase the economic efficiency of trees infected with WBDL.

In order to evaluate the effect of sodium nitroprusside (SNP) as nitric oxide donor (NO) on some morphophysiological and biochemical characteristics of cock's comb plant under cadmium stress, this experiment was designed as a complete randomized factorial design with three replications (pot with sand loamy soil) in greenhouse condition (temperature 25-30 °C, relative humidity 60%, and a 14/10 light–dark cycle) in spring and summer 2017. The first factor included two levels of Cd (30 and 60 mg.kg-1) with noncontaminated soil, and the second factor included three levels of SNPfoliar application (0,100 and 200μM). The results showed that with increasing Cd concentration, the activity of antioxidant enzymes, amount of hydrogen peroxide (H2O2), malondialdehyde (MDA), Cd in roots and shoots  increased, while the content of total chlorophyll, shoot and root dry weight decreased. On the other hand, the pplication of 100 μM SNP at the highest level of cadmium, compared to non-application, dramatically increased root dry weight (2.4 fold), cadmium concentration in the roots (51%), total chlorophyll (50%), proline (74%), and also, decreased H2O2 (28%) and MDA (41%). It seems that the application of this material caused further uptake of cadmium in the roots and prevent its translocation towards the shoots, can improve the adverse effects of cadmium by a reduction in oxidative damage.

The effect of nutrient solutions on the growth, development and flowering of calla lily was studied in a split plot design with completely randomized blocks design in soilless media cultures. The experiment was conducted with 16 treatments including four kinds of changed Quick nutrient solutions and four media cultures containing vermicompost and three replications and every replication included four pots. Results showed significant differences among different treatments regarding stem length, number of leaves, leaf area, number of flowers, spathe length, spathe width, root length, flowering period, pot life, amount of chlorophylls a, b, total and spathe anthocyanins. The highest number of leaves and the most amount of leaf chlorophylls resulted under the influence of nutrient solution 1 and vermicompost 5%. The highest root lenght resulted under the effect of nutrient solution 2 and vermicompost 5%. Treatment with nutrient solution 2 and vermicompost 15% showed the longest flowering period. Pot life of flower was longer than other treatments under the influence of nutrient solution 1 and without vermicompost. The highest number of flowers were seen as a result of nutrient solution 4 with vermicompost 5%. The amount of anthocyanins under the effect of nutrient solution 4 and vermicompost 10% was higher than other treatments. The largest stem diameter was obtained from nutrient solution 2 and vermicompost 15%. Also, it was concluded that nutrient solution 1 was more effective on vegetative characteristics of leaves because of having the most ammonium nitrate compared to other solutions and nutrient solution 2 had a significant effect on producing characteristics because of having the most potassium nitrate compared to other solutions.

MA×MA60 is a sweet cherry semi dwarf rootstock that is easily reproduced through micropropagation and because of the resistance to phytophytora, which is one of the most important factors in the deterioration of stone fruit trees, it is a valuable rootstock. The aim of this study was to investigate the effect of culture media and plant growth regulators on the proliferation and rooting of MA×MA60 rootstock at the Khorasan Razavi Agricultural and Natural Resources Research and Education Center. This experiment was conducted as a factorial in a completely randomized design with 4 replications. At the proliferation stage, the treatments consisted of three culture media (MS, WPM and DKW) and two growth regulators (benzyl amino purine and thiadiazuron) at concentrations of 0, 1 and 2 mgL-1 and at the rooting stage, treatments consisted of three culture media (MS, WPM and DKW) and different concentrations of indole-butyric acid (0, 1, 2 and 3 mgL-1). The results showed that in the proliferation stage, the highest number of shoots (33.6), leaves (20.33) and plantlet quality (3) were recorded in MS medium enriched with 2 mgL-1 of benzyl amino purine, and the shoot length (3.2 cm) in the MS medium enriched with 1 mgL-1 thiadiazuron. The highest rooting percentage (75%) and root number (5.33) were obtained in MS medium enriched with 3 mgL-1 indole buteric acid and DKW enriched with 2 mgL-1 indole buteric acid, respectively. Plantlets successfully adapted to the greenhouse conditions. Survival rate was about 75% in cocopeat and perlite culture.