مجله علوم و فنون باغبانی ایران
سال بیست و چهارم شماره 2 (تابستان 1402)

Greek marjoram (Origanum vulgare L. spp. hirtum) is a well-known aromatic plant belongs to the Lamiaceae family which is widely used in pharmaceutical, food, and cosmetic industries. Due to the economic importance of the plant, in the present study, morphological, phytochemical and antioxidant capacity of the plant were evaluated through the introducing of the plant to the climate of northern Tehran. According to the results, the mean plant height, leaf length, leaf width and pedicle length were 55, 2.5, 1.75 and 0.3 cm, respectively. Also, the average measured traits for plant fresh weight were 350 g, plant dry weight was 138.33 g and the ratio of plant fresh weight to dry weight was 2.53%. The yield of the plant in second year was 2899.8 kg/ha. The essential oil content of the plant at full flowering stage was 1.5%. Carvacrol (71.0 %), γ-terpinene (12.7 %) and ρ-cymene (6.9%) were the major compounds of the plant oil. The content of total phenol, total flavonoids and rosmarinic acid at full flowering stage were 29.34 mg GAE/g DW, 21.42 mg QE/g DW and 13.37 mg /g DW, respectively. The antioxidant activity of Greek marjoram extract showed the IC50 index of 99.11 μg/ml.

Pollination is very important to achieve an economic date product. This study has been conducted in the form of randomized complete block design (RCBD) on 15 trees of 12-year-old Medjool cultivar in three replications at the research garden of Jahrom Agricultural Research Station for two years. In this study, the effect of pollen grains 7001 as a control, 7004, 7013, 7030 and Boyer 11 tissue culture has been examined on the fruit quality traits. Based on the results of this experiment, the highest fruit pH (6.81), titrable acidity (TA) (0.19%), dry matter (80.73%) and fruit ash (2.61%) were observed using pollen grains7013. Pollinator genotypes had no significant effect on total soluble solids content. After pollen grain 7013, pollinator genotype 7030 showed the most positive effect on fruit quality traits, such as titrable acidity (0.18%), dry matter (80.60%) and fruit ash (2.58%). Among pollinator genotypes, 7013 and 7030 showed the most overlap with female flowers of Medjool cultivar.

Micrografting is an important technique supporting the micropropagation of a range of plant species, particularly woody plant species. In the past decade, in vivo and in vitro micrografting has become a strategy to facilitate shoot recovery and acclimatization of horticultural species. This experiment was conducted to study pistachio (P. vera L.) micrografting under in vivo condition and interaction of growth regulator and arbescular mycorrhizal fungi on micrografting success and stablishment. The scions were prepared from shoot tips of 6-7 years- old mature trees of " Ahmad Aghaie" cultivar and were micrografted on 14-deys- old "Qazvini" under controlled conditions. In order to examine the effect of mycorrhizal symbiosis on micrografting success and stablishment, inoculation of rootstooks with mycorrhizae (Funneliformis mosseae) was performed at the time of seed sowing. After floating the scions in ascorbic acid (0 and 400 mg L-1) for 60 min, they were treated with IBA (0, 50 and 100 mg L-1) and BA (0, 40 and 80 mg L-1). The results showed that, mycorrhizal inoculation had a positive influence on graft success percentage, survival percentage, scion growth, scion dry weight and leaf number. With the use of growth regulator, the success rate of micrografting increased so that the level of 100 mg L-1 of indolebutyric acid and 40 mg L-1 of benzyl adenine was observed to be more effective than other levels. In this study, ascorbic acid treatment had different effects, but in most cases it did not have a significant effect on micrografting, even in combination with growth regulators, the treatment had a negative effect. According to the results obtained from this study, it seems that the use of growth regulatorse and AM fungi had a positive effect on the survival rate of micrografted plants and these plants had a longer survival.

The cherry tomato is one of the most important cultivars of greenhouse tomato (Solanum lycopersicom) that has been welcomed and paid much attention in recent years. Like other cultivars, cherry tomatoes are sensitive to low light intensity, because of this; in the northern regions of Iran where natural sunlight is limited during autumn and winter, light conditions are not appropriate for indoor tomato cultivation. To alleviate this problem, an experiment was designed to evaluate the effect of two factors consisting of silicon (at two levels: 0 and 1 millimolar) and carbohydrate nutrition (at five levels: control, sucrose 2%, sucrose + potassium nitrate 5 g L-1, sucrose + magnesium nitrate 5 g L-1, sucrose + boric acid 0.5 g L-1) on the quantitative and qualitative traits of cherry tomatoes in greenhouse conditions. The results showed that the lowest flower fall was obtained in the treatment of silicon with sucrose + potassium, but it was not significantly different with the treatment of sucrose + boron. The sucrose + boron treatment which produced a high number of flowers, also increased fruit set, and the highest number of fruit per plant belonged to this treatment. The highest leaf silicon concentration was observed in plants treated by silicon treatment combined with sucrose + boron. In this experiment, sucrose + boron exhibited the lowest leaf sugar content, which was not significantly different from sucrose + potassium and silicon treatments. Since sucrose + potassium treatment had the highest amount of stem and root sugar, it is obvious that leaf carbohydrate depletion in this treatment was done toward the stem and root. The highest percentage of soluble carbohydrates was recorded in the sucrose + boron treatment, which clearly showed that in this treatment, soluble carbohydrates moved from the leaf source to the fruits. Overall, the results showed that silicon treatment in the absence of sucrose foliar application caused the depletion of sugars from the leaves and the movement of carbohydrates to fruits, but reduced the export of carbohydrates to the roots. It seems that the transfer of carbohydrates to the fruit occurred after the foliar application of silicon; because of this, silicon could reduce flowering fall and increase plant yield.

This study aimed to investigate the effect of cultivation methods and different organic matters (vermicompost, Licorice root waste and manure) on glycyrrhizic acide contant and morphophysiological characteristics of Licorice (Glycyrrhiza glabra L.). Treatments comprised of two cultivation methods (transplanting and direct seeding) in combination with three types of organic matter (vermicompost, Licorice root waste and manure) at four levels of 0, 10, 20 and 40 tons per hectare. Results showed that the highest root fresh and dry weight was achived in transplanting method in 40 tons per ha of each manure. The highest starch content was attained from transplanting method in addition vermicompost at 20 and 40 tons per ha with no significant differences. The amount of root sodium in transplanting cultivation method and application of vermicompost and manure was significantly higher than the application of Licorice waste root together with seedling cultivation method.The highest amount of root potassium was obtained in the application of 40 ton per ha of Licorice waste root and manure.The maximum glycyrrhizic acid percent was recived in the application of 20 ton per ha of licorice waste root and the highest glycyrrhizic acid yield per ha was obtained from transplanting method plus application of manure at 20 and 40 tons per ha and Licorice root waste at 20 ton per hectare with no significant differences. In general, transplanting method as well as application of 20 to 40 tons per hectare manure or 20 tons per hectar of Licorice root waste is recommended.

Supplementary irrigation in the fig orchards of the shores of Bakhtegan Lake in Estahban is done with saline water. This research was carried out to investigate the effect of saline water on vegetative and reproductive characteristics of fig trees. The randomized complete block design was performed with irrigation water salinity treatments (2, 4, 6 and 8 dS.m-1) in two irrigation intervals (once every 15 and 30 days) with a non-irrigation treatment (control) on Sabz cultivar in three replications at Khanehkat village in the years 2018 to 2021. The results showed that irrigation with 8 dS.m-1 salinity had adverse effects and it was an unsuccessful treatment compared to the other treatments with lower salinity irrigation. The highest abnormality symptoms in vegetative and reproductive factors were observed in the control treatment. Also, this treatment has the lowest relative water content (58.6%), diameter (26.6mm) and weight (4.3g) of fruit, the least yield (4935g) and the percentage of first-class commercial fruits (Open ostiole, white and large fruits) and the highest leaf ionic leakage (27.1%), which was significantly different from most of the treatments. There was a great similarity in the characteristics of trees treated with 8 dS.m-1 saline water and without irrigation. Therefore, supplementary irrigation with this salinity is not recommended. In conclusion, supplementary irrigation with saline water less than 6 dS.m-1 had suitable quantity and quality of fruit and the least abnormality signs. So, Sabz cultivar can tolerate until this amount of salinity.

Flooding stress causes a lack of oxygen and impaired root activity, part of which is related to the possible effects of aquaporins.The factorial experiment was performed in a CRD design with treatments including the flooded plants with active aquaporin and the flooded plant with active aquaporin at two or 10 days after stress. With the loss of aquaporin activity, the fresh and dry weight of the shoots and roots decreased and the duration of the stress did not affect it. The potential of leaf and root water in aquaporin’s-free flood stress was more negative than in flood and control, and the potential of root water under long-term flood stress was more negative than the short-term stress. The content of abscisic acid in flood stress increased so that in the presence of aquaporin for a long time it increased the abscisic acid and in the absence of aquaporin increased in a short time. Expression of the root and leaf aquaporin gene increased in flooding stress and the absence of aquaporin in the long term decreased in the short term. In general, the antioxidant index was more affected by the duration of stress. The amount of potassium and abscisic acid in the plant increased in the absence of aquaporin to maintain the water content of the plant by closing the stomata. On the other hand, carotenoids as a precursor to the production of abscisic acid increased. In general, the presence of root aquapurins seems to play an important role in maintaining water balance in pepper in flooded conditions.

Phalaenopsis amabilis with facultative CAM photosynthetic mechanism is one of the most valuable ornamental plants in the world. This plant's most common method of propagation is through its in vitro culture. In tissue culture plants, photosynthesis is strongly affected by many factors. The role of photosynthesis of in vitro plantlets in their performance and acclimation is still unknown. In the present study, photosynthetic performance was investigated based on gas exchange and fluorometry in Phalaenopsis under in vitro conditions for two periods, including short-term (2 weeks) and long-term (8 weeks), and four times of recording during the day. The aim was to investigate the stomatal and photosynthetic behavior of Phalaenopsis plantlets under these conditions. According to the obtained results based on the gas exchanges and chlorophyll fluorometry, the rate of photosynthesis and the quantum yield of plantlets in vitro significantly affected the ability of plantlets to regenerate and create relative adaptation in plant cells under high humidity conditions. Photosynthetic and quantum performances in the long-term culture period were better than their performance in the short-term, while non-photochemical quenching (NPQ) and heat loss were decreased in the plantlets grown in the long-term culture period. The total chlorophyll and carotenoid content were also higher in the long-term than in the short-term. The performance of the stomata was disturbed due to high humidity for a long-term period. So, the effect of the stomata on photosynthesis in the plantlets was almost ineffective under in vitro conditions. Therefore, the finding showed flexibility, better photosynthetic and physiological performance for Phalaenopsis plantlets under in vitro conditions, and better adaptation to stress.

This study was carried out to optimize in vitro micropropagation of fig tree cultivar Sabz. Initially, a completely randomized design (CRD) experiment consisting of different concentrations of cefotaxime was performed to identify the best antibiotic treatment to control internal bacterial infections. In the establishment stage, a CRD-factorial experiment included two culture media (MS and WPM), and different concentrations of BA (0, 0.5, 1, and 1.5 mg L-1) were performed to select the best establishment treatment. After four weeks, survival rate percentage, leaf number, and stem length indices were evaluated. In the shoot proliferation stage, MS salt medium enriched with different concentrations of BAP (0, 1, 2, and 3 mg L-1) in combination with IBA (0, and 0.1 mg L-1) were used. The results revealed that internal bacterial infections were successfully eliminated using 100 mg L-1 cefotaxime. In addition, the highest established explant rate (100%) was observed in the MS medium containing 0.5 mg L-1 BAP, which was significantly higher than the WPM medium (76.49%). Also, the results showed that the most significant number of proliferated shoots and leaf numbers were observed in treatments of 2 mg L-1 BAP + 0.1 mg L-1 IBA and 2 mg L-1 BAP (2.90 and 2.41 shoots, and 7.77 and 6.78 leaves, respectively). In addition, the highest shoot length was seen in treatments of 1 mg L-1 BAP + 0.1 mg L-1 IBA, control and 1 mg L-1 BAP (1.96, 1.48, and 1.51, respectively).

Climate change has affected the rates of chilling and heat accumulation, which are vital for flowering and production in temperate fruit trees. In this study, the chilling requirement of kiwifruit was analyzed by using the dynamic (CP) and chilling hours (CH) model, and the heat requirement was analyzed by using the growing degree Hours (GDH) model. The results shown that high temperatures at bud swell or woolly bud phase led to the acceleration of the different stages of bud phenology. Also, reduction of chilling requirement delays the events of bud phenology. In addition, a linear and significant relation was observed between chilling requirement and heat accumulation. So, the flowering time of kiwifruit cultivar “Hayward” was significantly affected by the timing and interaction of received chilling and heat accumulation. In the cuttings that received 954 and 1194 chilling hours, the heat requirement for breaking vegetative buds was 10543 GDH and 8251 GDH respectively. With cold-continuing, the heat requirement for breaking buds decreased, and flowering was done in shorter periods. The obtained results showed that the amount of chill recieved is effective in the percentage of bud break, and the number of flower buds formed. Also, the chilling requirements for maximum bud breaking were about 725 CH, and the chilling requirements for maximum flowering were above 954 CH in Hayward cultivar.