Medicinal Plants
Mehrab Yadegari
Abstract
IntroductionAgave americana cv. marginata from Agavaceae family is one of the important plants have many uses in various medicinal and food industrial. Among environmental stresses, water deficit stress plays an important role in the biosynthesis of secondary metabolites in medicinal plants in arid and ...
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IntroductionAgave americana cv. marginata from Agavaceae family is one of the important plants have many uses in various medicinal and food industrial. Among environmental stresses, water deficit stress plays an important role in the biosynthesis of secondary metabolites in medicinal plants in arid and semi-arid regions like Iran. Drought stress has detrimental effects on growth and yield and can upset the balance between the antioxidant defense system and free radicals by stimulating a series of biochemical reactions, where free radicals cause cell damage. In sustainable production systems of medicinal and aromatic plants, stable quantitative and qualitative functions can be achieved under conditions of environmental stress and it is possible to improve the production of secondary metabolites in these plants under adverse environmental conditions. Therefore, this study was done to evaluate some of important macro-micro nutrients on the morpho-physiological and phytochemical properties of Agave americana cv. marginata to determine and introduce the best combinations of fertilizers with use of superabsorbent nano-polymer under water stress conditions. Materials and MethodsThis research was performed in randomized complete block design (RCBD) in a split-split plot layout with three replications. Irrigation regimes (D1-D3: Field Capacity, 50% and 75% evaporation from basin class A) in main plots, superabsorbent nano-polymer application (S1-S2: use and not use) in sub plots and treatments of fertilizers [F1-F15: grow-more 1 (F1), grow-more 2 (F2), grow-more 3 (F3), iron chelate (F4), zinc chelate (F5), grow-more 1+iron chelate (F6), grow-more 1+zinc chelate (F7), grow-more 2+iron chelate (F8), grow-more 2+zinc chelate (F9), grow-more 3+iron chelate (F10), grow-more 3+zinc chelate (F11), grow-more 1+iron chelate+zinc chelate (F12), grow-more 2+iron chelate+zinc chelate (F13), grow-more 3+iron chelate+zinc chelate (F14) and control (F15)] in sub-sub plots were done. This research was performed in greenhouse condition of Islamic Azad University Branch of Shahrekord (latitude. 32°20′ N, longitude. 50°51′ E, altitude. 2061 m) in 2023-2024. In each year, fertilizer treatments were applied in foliar application after stage of V8 (plants had 8 leaf) in 6 stage by 14 days interval and harvesting was done after one month after the final application of fertilizers. The fertilizers of grow-more (NPK), iron and zinc in 4 gr.l-1 concentration by production company certification were used in V8 stage in plants and the effects were compared by control plants. Weed control was done manually during the entire experiment. During the experiment no systemic pesticide and herbicide were used. The harvested shoots transferred to the laboratory for measure of characters. Morphological characters such as leaf length, leaf diameter and dry/fresh root/leaf weight; physiological characters such as chlorophyll a, b, total chlorophyll and zinc, iron and nitrogen content in root/leaf and phytochemical characters such as contents of hecogenin, saponin, protein of leaf and root were measured. For assessment of the total chlorophyll content of A.americana, the leaves were extracted with 80% acetone. The absorbance of the extraction was read at 470, 648, and 664 nm, and the content of total chlorophyll was calculated as mg per g leaf fresh weight. For measure of hecogenin, saponin, total protein in leaf and root and nitrogen content in leaf and root use the protocols of Hackman et al., 2006, Sidana et al., 2016, Bradford, 1976 and Álvarez-Chávez et al., 2021; respectively. Results and DiscussionIn two sequential years, the obtained results showed that the use of treatments increased the characters and made the significant effectiveness. The most of means of leaf dry weight (30.11 g.plant-1), leaf fresh weight (207.33 g.plant-1), root dry weight (3.82 g.plant-1), root fresh weight (18.79 g.plant-1), length of leaf (64.55 cm), leaf diameter (0.41 centimeter), chlorophyll a (2.27 mg.g-1 fresh weight), chlorophyll b (0.53 mg.g-1 fresh weight), total chlorophyll (2.81 mg.g-1 fresh weight), hecogenin (35.48 mg.kg-1 fresh weight), saponin (66164.8 mg.kg-1 fresh weight), nitrogen of leaf (1.39 mg.g-1 dry weight), nitrogen of root (1.23 mg.g-1 dry weight), protein of leaf (25.34 mg.g-1 dry weight), protein of root (16.99 mg.g-1 dry weight), zinc of leaf (68.99 microg-1 dry weight), zinc of root (44.84 microg-1 dry weight), iron of leaf (81.01 microg-1 dry weight) and iron of root (49.84 microg-1 dry weight) made in grow-more fertilizers specially grow-more 1 (20-20-20) in combination with Fe/Zn Libfer. However the superabsorbent nano-polymer application had the aggressive effectiveness on amounts of characters especially in hardness of water stress. The least morpho-physiological and phytochemical characters such as leaf dry weight (12.81 g.plant-1), leaf fresh weight (89.54 g.plant-1), root dry weight (1.62 g.plant-1), root fresh weight (8.18 g.plant-1), length of leaf (41.12 cm), leaf diameter (0.24 centimeter), chlorophyll a (1.69 mg.g-1 fresh weight), chlorophyll b (0.26 mg.g-1 fresh weight), total chlorophyll (1.95 mg.g-1 fresh weight), hecogenin (21.88 mg.kg-1 fresh weight), saponin (22134.3 mg.kg-1 fresh weight), nitrogen of leaf (0.29 mg.g-1 dry weight), nitrogen of root (0.77 mg.g-1 dry weight), protein of leaf (10.11 mg.g-1 dry weight), protein of root (6.47 mg.g-1 dry weight), zinc of leaf (34.34 microg-1 dry weight), zinc of root (20.36 microg-1 dry weight), iron of leaf (43.77 microg-1 dry weight) and iron of root (27.73 microg-1 dry weight) made in control plants. In most of measured characters the treatments of D1S1F12, D3S1F14 and D2S1F14 were the best and control plants had the least of characters.ConclusionGenerally the application of grow-more fertilizer 1 (20-20-20) with consumption of zinc and iron fertilizers can be a good strategy to improve the morpho-physiological and phytochemical characters of Agave americana cv. marginata specially the hecogenin and saponin amounts in the water stress conditions. However the use of superabsorbent nano-polymer in strenuous drought stress (75 %) is more effectivnes than other water stress levels.
Medicinal Plants
M. Yadegari
Abstract
Introduction
Satureja bachtiarica is one of the important endemic species and is used in medicinal and food industries. This plant is rich in essential oil, flavonoids, monoterpene glycosides and trypanocidal terpenoids. The main compounds of the essential oil from S.bachtiarica L. collected from natural ...
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Introduction
Satureja bachtiarica is one of the important endemic species and is used in medicinal and food industries. This plant is rich in essential oil, flavonoids, monoterpene glycosides and trypanocidal terpenoids. The main compounds of the essential oil from S.bachtiarica L. collected from natural habitats are alpha-pinene, p-cymene, carvacrol and gamma-terpinene. The environmental factors cause changes in the growth, quantity, and quality of active substances (such as alkaloids, glycosides, steroids and volatile oils) in medicinal and aromatic plants. Among environmental stresses, water deficit plays an important role in the biosynthesis of secondary metabolites in medicinal and aromatic plants in arid and semi-arid regions like Iran. Drought stress has detrimental effects on growth and yield and can upset the balance between the antioxidant defense system and free radicals by stimulating a series of biochemical reactions, where free radicals cause cell damage. In sustainable production systems of medicinal and aromatic plants, stable quantitative and qualitative functions can be achieved under conditions of environmental stress and it is possible to improve the production of secondary metabolites in these plants under adverse environmental conditions. Therefore, this study was done to evaluate the amino acids on the physiological and phytochemical properties of S. bachtiarica to determine and introduce the best amino acids under water stress.
Materials and Methods
This investigation was done from spring (May) 2022 to fall (September) 2023 at the Research Farm of Islamic Azad University, Branch of Shahrekord (latitude. 32°20′ N, longitude. 50°51′ E, altitude. 2061 m). Based on the Köppen climate classification, the climate of the study area is classified as cold and semiarid. This study was conducted in a randomized complete block design (RCBD) as a split plot layout with three replications. Irrigation regimes (3-day, 6-day, and 9-day intervals) were assigned as the main plots, while the foliar application of amino acids (methionine, lysine, phenylalanine, and proline) was designated as the subplots. In each year, treatments were applied at 3 stages (3 months after sowing, end of vegetation, before flowering, beginning of flowering and early flowering) and harvesting was done in the complete flowering stage. Weed control was applied manually during the entire experiment. During the experiment, no fertilizer and no systemic pesticide and herbicide were used. The harvested shoots were transferred to the laboratory for extracting and analysis of the leaves and stems of treated plants. For assessment of the total chlorophyll content of S. bachtiarica, the leaves were extracted with 80% acetone. The absorbance of the extraction was read at 470, 648, and 664 nm, and the content of total chlorophyll was calculated as mg per g leaf dry weight. Total phenol content was measured by the Folin-Ciocalteu reagent as reported by Singleton and Rossi. The total phenol content was expressed as mg of gallic acid equivalent per g leaf dry weight according to standard curves of gallic acid. The essential oils were extracted by hydro-distillation and analyzed using GC/MS.
Results and Discussion
Applied amino acids significantly influenced the morpho-physiological and phytochemical characters of Satureja bachtiarica. In two years, the highest chlorophyll content (1.41-1.54 mg.g-1 FW) and total phenol content (2.45-2.72 mg.g-1 FW) were obtained in methionine (2.5 g.l-1) and phenylalanine (100 µM) treatments by irrigation regimes 3-day interval. The highest essential oil contents (1.09-1.61 %) were obtained from the plants treated by methionine (2.5 g.l-1) and phenylalanine (100 µM) treatments by irrigation regime 3 days interval. The main chemical compounds of essential oil were P-cymene (17.12-19.45 %), gamma-terpinene (18.14-16.87 %) and Carvacrol (45.12-51.24 %) belonging to cyclic monoterpenes. The treatments had significant effectiveness on cyclic monoterpens such as alpha-terpinene, gamma-terpinene, germacren-d, carvacrol, thymol and p-cymene. Increasing of essential oil content/composition by use of amino acids was seen. The main components of essential oil in plants treated by proline were lesser than other treated plants. In two years of this research amino acids of methionine and phenylalanine mad the most amounts of carvacrol and essential oil content. The monoterpene alcohols in volatile oils of the treated plants with amino acids elicitors considerably were higher than the sesquiterpenes. According to the ratio of monoterpenes alcohol to sesquiterpenes in volatile oils of the treated S. bachtiarica with different elicitors, the foliar application of amino acids can improve the odor quality of S. bachtiarica volatile oil.
Conclusions
Foliar application of methionine (2.5 g.l-1) and phenylalanine (100 µM) treatments better than other treatments increased the morpho-physiological and essential oil attributes. Environmental conditions such as drought play a key role in plant growth and biosynthesis of different metabolic compounds. The observed variation in shoot yield and phytochemical content of S. bachtiarica during the studied years may related to differences in photoperiod, temperature, solar radiation, precipitation and occurrence of biotic and abiotic stresses at different growing seasons. Also amino acids had very important effectiveness on content/composition of essential oil of S. bachtiarica. Generally, treats of methionine and phenylalanine can be a good strategy to improve morpho-physiological characteristics and essential oil quantity and quality of S. bachtiarica in the same climate.
Medicinal Plants
Mehrab Yadegari
Abstract
Introduction
Hyssopus officinalis L. belongs to the family Lamiaceae, and is one of the endangered endemic species in Iran. This plant is rich in essential oil, flavonoids, monoterpene glycosides, trypanocidal terpenoids, rosmarinic acid, and linolenic acid6. The main compounds of the essential oil ...
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Introduction
Hyssopus officinalis L. belongs to the family Lamiaceae, and is one of the endangered endemic species in Iran. This plant is rich in essential oil, flavonoids, monoterpene glycosides, trypanocidal terpenoids, rosmarinic acid, and linolenic acid6. The main compounds of the essential oil from H. officinalis L. collected from natural habitats are α-pinene, Sabinene, 3-Carene, Beta-Pinene, Cis- Pinocamphone, Myrtenol, Pinocamphone and Camphor. The environmental factors cause changes in the growth, quantity, and quality of active substances (such as alkaloids, glycosides, steroids and volatile oils) in the medicinal and aromatic plants. Among environmental stresses, water deficit stress plays an important role in the biosynthesis of secondary metabolites in medicinal and aromatic plants in arid and semi-arid regions like Iran. Drought stress has detrimental effects on growth and yield and can upset the balance between the antioxidant defense system and free radicals by stimulating a series of biochemical reactions, where free radicals cause cell damage. In sustainable production systems of medicinal and aromatic plants, stable quantitative and qualitative functions can be achieved under conditions of environmental stress and it is possible to improve the production of secondary metabolites in these plants under adverse environmental conditions. Therefore, this study was done to evaluate the organic elicitors on the physiological and phytochemical properties of H.officinalis to determine and introduce the best elicitor under water stress.
Materials and Methods
This investigation was done from spring (May) 2022 to fall (September) 2023 at the Research Farm (latitude. 32°20′ N, longitude. 50°51′ E, altitude. 2061 m). Based on the Köppen climate classification, the climate of the area of study is classified as cold and semiarid. The present study was conducted in a randomized complete block design (RCBD) with three replications to investigate the effect of foliar application of different organic elicitors (chitosan, salicylic acid and phenylalanine) with control level (without any spraying) on the physiological and phytochemical characters of H. officinalis L. In each year, treatments were performed in 3 stages (end of vegetative, beginning of flowering and 50% of flowering) and in full flowering, harvesting was done. 3 irrigation regimes (4, 6, 8 day interval) in main plots and foliar application of elicitors in sub plots were done. The essential oils were extracted by hydro-distillation and analyzed using GC/MS.
Results and Discussion
According to obtained results, applied organic elicitors significantly influenced the physiological and phytochemical characters of H. officinalis L. However the assayed traits showed slightly variation during the studied years. In two years, the highest chlorophyll content (17.12-17.31 mg.Kg-1 FW) and total phenol content (1.77-1.81 mg.g-1 DW) were obtained in chitosan (0.5 mg.l-1) and phenyl alanine (1000 mg.l-1) treatments respectively. In most of measured characters, plants treated with chitosan (0.5 mg.l-1) and phenyl alanine (1000 mg.l-1) were in the same group. Amounts of some characters in plants treated with phenyl alanine (2000 mg.l-1) and salicylic acid (3 mM) lesser than control plants. The main constituents of essential oil were Sabinene, 3-Carene, Beta-Pinene, Cis- Pinocamphone, Myrtenol, Pinocamphone and Camphor (cyclic monoterpenes) that made the most components of essential oil plants. Among of elicitors, the chitosan effect on increasing of physiological and phytochemical characters such as the chlorophyll content was higher than other elicitors. Applied elicitors showed significant effects on essential oil content and composition of H. officinalis L. The highest essential oil content (0.89-0.91 %) was obtained from the treated plants by chitosan (0.5 mg.l-1). According to the biennial results of the chemical analysis of the essential oils from plants treated with treatments by GC/MS, the most important chemical compounds that determine the quality of H. officinalis L. essential oil including Beta-Pinene (17.93-18.53 %), Pinocamphone (24.97-25.12 %) and Cis-Pinocamphone (42.87-45.12 %) were identified. Cis-Pinocamphone belonging to bicyclic monoterpene was the predominant constituent of essential oil of H. officinalis L.
Conclusion
According to the results of this study, water deficit stress caused significant phytochemical changes in the H. officinalis L. essential oil. The main constituents of the volatile oils of H. officinalis L. were Sabinene, 3-Carene, Beta-Pinene, Cis- Pinocamphone, Myrtenol, Pinocamphone and Camphor were identified in the H. officinalis essential oil. Generally, Foliar application of chitosan and phenyl alanine significantly increased the monoterpenes compounds in essential oils of Hyssopus officinalis L., so that the content of these compounds and essential oil content in treated plants by organic elicitors 63% was more than the control plants. Finally, the application of chitosan at 0.5 mg.l-1 can be a good strategy to improve physiological and essential oil quantity and quality of H. officinalis L. in cold and semi-arid climates.
Pomology
Esmaeil Safavi; Mehrab Yadegari; Seyyed Asghar Mousavi; Bijan Haghighati
Abstract
Introduction
Water shortage is very frequent in many countries, and, together with the rising demand for industry, growth of human population, climate change and specifically the trend towards irrigated agriculture, has led to widespread problems of water scarcity, especially in Middle East countries. ...
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Introduction
Water shortage is very frequent in many countries, and, together with the rising demand for industry, growth of human population, climate change and specifically the trend towards irrigated agriculture, has led to widespread problems of water scarcity, especially in Middle East countries. This situation imposes the need to optimize water use in all human activities. Among the different productive uses of water, agriculture is by far the main water user in most water scarce regions and, consequently, any potential improvement in the use of the available water resources may play a significant role toward achieving a more sustainable use of water. Plant responses to water deprivation are usually monitored through selected morphological and physiological parameters which have been proven to be good indicators of drought in different studies. Some of the most important standards for evaluating plant genotypes under drought stress are measurements of morphological parameters such as height, leaf characters and root growth.
Materials and Methods
To compare the growth response of different almond cultivars to different levels of water stress, an experiment was conducted as a split plot in the base of randomized complete block design with three replications in the Agricultural and Natural Resources Research Center of Chaharmahal and Bakhtiari Province in two growing season 2019-2020 and 2020-2021. Different irrigation periods based on the percentage of usable soil moisture between filed capacity to wilting point, including 70% filed capacity (control or no stress), 50% filed capacity (mild stress), 30% filed capacity (medium stress) and 10% of field capacity (severe stress) were considered as the main factor of the experiment. The sub-factor included 14 commercial cultivars of almonds (Mamaei, Rabi, Saba, Araz, Eskandar, Aidin, Shahrood 6, 7, 8, 10, 12, 13 and 21 and GN vegetative rootstock), all of which were grafted on GN rootstock. In this study, uniformly grafted seedlings in terms of age, stem diameter and height were selected and planted. In the second year after planting the seedlings, in order to apply drought stress, tubes for hygrometer (TDR) were installed in each experimental plot and based on soil moisture content, irrigation cycle was determined for different treatments.
Results and Discussion
In both years, three months after applied water stress growth traits and nutrient concentrations in the leaves of treated seedlings were measured. Based on the results of analysis of variance, the morphological traits of almond seedlings were significantly affected by cultivar type and drought stress level. In all almond cultivars, the highest height was belonged to seedlings that were grown in non-stress conditions and with increasing the drought stress intensity, the height of almond seedlings was decreased. Under severe drought stress, GN and Mamaei cultivars had the highest (183.93 cm) and the lowest (94.60 cm) height, respectively. Seedling height in GN, Shahrood 12, Saba and Shahrood 10 cultivars showed the lowest decrement under severe drought stress. In all cultivars, drought stress caused a significant reduction in the length and width of the seedlings crown, and the greatest decreasing was recorded in severe drought stress (10% FC). Under severe drought stress, cultivar GN had the largest crown and cultivars Rabi, Shahrood 7 and Eskandar had the smallest crown. Increasing the drought stress intensity significantly reduced the branches growth of seeding in terms of number and length of sub-branches. As the intensity of drought stress increased, the length of sub-branches decreased however the number of intermediates in sub-branches increased. In non-stressed condition, the cultivar GN had the longest branch (55.95 cm), which was significantly higher than the other studied almond cultivars. The shortest branches were also observed in Saba (29.94 cm) and Eskandar (29.47 cm) cultivars. Increasing drought stress caused a significant reduction of leaf area in all studied cultivars and the highest decreasing was observed under severe drought stress. The GN (37.76 cm²) and Shahrood 10 (31.81 cm²) had the highest leaf area in non-stress and drought stress conditions. Under severe drought stress (10% FC) cultivar Shahrood 6 showed the lowest leaf area. The results of this study showed that increasing the intensity of dehydration significantly reduced the amount of nitrogen, phosphorus, manganese and zinc in the leaves of the studied cultivars of almonds, however, the amount of potassium and iron in stressed plants increased under drought stress. Based on the results of the present study, under severe drought stress the GN, Shahrood 8 and Shahrood 12 cultivars in terms of growth indices including seedling height, stem diameter, canopy growth, branch growth and concentration of macro and micro elements was superior compared with the other studied cultivars.
Conclusion
Based on the results of this study, drought stress significantly reduced growth indices and nutrient concentrations, although the reaction of almond cultivars to different levels of drought stress was different. In this study, among the studied almond cultivars GN, Shahrood 8 and Shahrood 12 cultivars in terms of growth characters including seedling height, stem diameter, canopy growth, branch growth and concentration of macro and micro elements showed higher tolerance to different level of drought stress. These cultivars less affected by the high intensities of dehydration. Therefore, GN, Shahrood 8 and Shahrood 12 cultivars can be used in future studies to evaluate the possibility of cultivating these cultivars in areas with water deficit.
Pomology
Mostafa Alizadeh; Mehrab Yadegari; Gholamhossein Davarynejad; Seyyed Hossein Nemati
Abstract
Introduction Pear (Pyrus communis L.) is one of the major fruit trees in the world which grown in temperate zones. In pear breeding program the bigger fruit size with better quality as well as market acceptability are usually in interest. In fruit trees, the size and yield of fruit are closely depended ...
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Introduction Pear (Pyrus communis L.) is one of the major fruit trees in the world which grown in temperate zones. In pear breeding program the bigger fruit size with better quality as well as market acceptability are usually in interest. In fruit trees, the size and yield of fruit are closely depended on cultivar and rootstocks. The variations of nutrient uptake, water use efficiency, photosynthesis performance, and resistance to biotic and abiotic stresses have been reported among different combinations of cultivars and rootstocks. Therefore there is a close relation between cultivar and rootstock with yield and quality of produced fruits. In recent years the semi dwarf clonal rootstocks of pear including OH×F, Pyro and FOX series have received more attention. However the performance of these rootstocks varies depending on scion cultivar, climatic condition, soil type, and planting system. Materials and Methods This experiment was conducted to assay the growth characters and fruit yield of Dargazi and Louise Bonne (Beyrouti) grafted onto PyroDwarf and OH×F69 rootstocks at the Orchard of Astan Quds Razavi, Mashhad, Iran (36°17' N, 59°36' E; altitude. 985 m) during 2018-2019 and 2019-2020. The experiment in both consecutive years was done as a factorial in the base of randomized complete blocks with four replications. The studied cultivars were grafted onto PyroDwarf and OH×F69 rootstocks in late spring 2016. The used water was pit water with 695 µSiemens/cm EC and pH 7.17. Evaluation of plant growth was carried out at the end of the season. The studied traits were included tree height, internode length, vertical and horizontal growth of shoots in the current season, trunk diameter above, below and in the grafting line, leaf area, shoots angel and the number of sucker per tree. These characters were assayed in three trees per each replication. The trunk diameter at the below and above the grafting line was calculated according to trunk circumference that was measured at 10 cm above and below the grafting point. Leaf area in each tree was assayed with area measuring device. Flowering characteristics (start blooming and end of bloom) were determined. Fruit ripening season was also recorded. Yield of trees was assayed by weighting of produced fruits in each tree with a digital scale. The combined analysis of obtain data was conducted by SPSS and differences among means of data were determined by Duncan's multiple ranges test at P≤0.05. The reported data was the mean of two studied years.Results and Discussion The obtained results showed the variation in growth and bearing properties of different combinations of Beyrouti and Dargazi cultivars with PyroDwarf and OH×F69 rootstocks throughout the studied years. The analysis variance showed the significant effect of year, cultivar and rootstock on growth characteristics of pear tree. Also the interaction effects of cultivar and rootstock were significant on tree growth response with exception of internode length. The most studied parameters showed a significant increasing during the two consecutive years. During the studied years the height and width of pear trees were increased up to 10.44 and 14.54%, respectively and the trunk diameter was increased by 10%. According to obtained results the growth of Dargazi cultivar was higher than the Beyrouti cultivar. The effect of OH×F69 rootstock on growth increasing of studied cultivars was prominent than PyroDwarf regards to tree height, shoot length and internode length. However the highest trunk diameter and leaf area density of both cultivars was found in PyroDwarf rootstock. Although the time of blooming and fruit ripening of each cultivar was not influenced by the rootstock but the bearing characters were varied between the Dargazi and Beyrouti cultivars. The highest yield of pear fruit was obtained in Dargazi cultivar and grafting onto PyroDwarf rootstock significantly enhanced the fruit yield in both cultivars.Conclusion The rootstocks have a key role on growth and yield of pear trees as well as their responses to abiotic stress. Rootstocks through influencing the physiological characteristics of grafted scions regulate the quantity and quality of produced fruits. The results of present study showed the variation in growth and bearing properties of different combinations of Beyrouti and Dargazi cultivars with PyroDwarf and OH×F69 rootstocks throughout the studied years. The PyroDwarf rootstock greatly reduced the tree growth and enhanced fruit yield of both Dargazi and Beyrouti cultivars. According to the obtained results the PyroDwarf rootstock is recommended for Dargazi cultivar to reach the highest pear fruit yield under similar environmental condition of present study.
