Sara Khorasaninejad; Hassan Soltanloo; Javad Hadian; Sadegh Atashi
Abstract
Introduction: Plants are usually exposed to different environmental stresses which limit their growth and productivity as well as cause considerable loss of worldwide agricultural production. One of the most important factors affecting plant and production of secondary metabolites is the salt stress. ...
Read More
Introduction: Plants are usually exposed to different environmental stresses which limit their growth and productivity as well as cause considerable loss of worldwide agricultural production. One of the most important factors affecting plant and production of secondary metabolites is the salt stress. Salinity of soil or water is one of major stress, obstacles to increase production in plant growing areas throughout the world and especially in arid and semi-arid regions it can severely limit plant production. Iran is among the world's arid and semi-arid land, and faces water resources shortage and saline lands. According to the concept of sustainable development and role of Agriculture, using saline water and soil resources seems mandatory. Recently, medicinal and aromatic plants have received much attention in several fields such as agroalimentary, perfumes, pharmaceutical industries and natural cosmetic products. Although, secondary metabolites in the medicinal and aromatic plants were fundamentally produced by genetic processing, but, their biosynthesis are strongly influenced by environmental factors. It means that biotic and abiotic environmental factors affect growth parameter, essential oil yield and constituents. Abiotic environmental stresses, especially salinity and drought have the most effect on medicinal plant. Medicinal plants cultivation is one of ways to exploit these resources. Essential oils help to easier adapt to the environmental stress conditions. Also, essential oils are not constantly in the quantitative and qualitative terms. They are changing continuously, due to the requirements of the environment, and to individual survival. The different results were dedicated from the effect of salinity stress on the quantitative and qualitative parameters. Lavender (Lavandula angustifulia Miller) is a perennial woody medicinal plant that cultivated for its an essential oil in leafs and flowers. Major parts of Lavender produces essential oil are flowers and leaves.
Materials and Methods: This experiment was carried out using a randomized complete block design with three replications to study the effect of salinity stress on growth parameters, essential oil constituents and yield of Lavender (Lavandula angustifulia) at the Horticultural Sciences Department, Plant Product faculty, Gorgan Agricultural Sciences and Natural Resources University. Lavender plants were obtained from seed plantation. The seeds in this investigation were obtained from the Institution of Forests and Range researches in Tehran. After three weeks stratification (4ºC) and germination, five plants were transplanted into similarized pots that were filled with perlite and cocopeat (2:1). Irrigation treatments with hydroponic solution were completed during germination until stage of 6-8 leaf. Then, five levels of salt stress, including 0, 25, 50, 75 and 100 mM NaCl levels were investigated during four months, applied in hydroponic. Length, shoot wet weight, root wet weight and root dry weight were measured at full flowering stage (after five months). The same time in order to evaluate percentage and composition essential oil, each plant were harvested and dried under room condition. After two weeks, Clevenger method was used to extract the essential oil from the plant foliage. The obtained essential oil were measured for calculating of essential oils percentage and then, analyzed by using GC/MS (Gas choromatography-mass spectrometry) for identification and quantification of the components. Statistical analysis of data was used with SAS software and charts preparing was done with Excel software. Mean comparison with LSD’s test in 5 percent probability was used.
Results and Discussion: Results indicated that salinity stress motivated a significant influence in all of the growth parameters and essential oil yield and percent in P < 0.05. Increasing salt of the soil led to reduce in stem length, shoot wet weight, root wet weight and root dry weight and increase length of root and leaf essential oil percent at first, and then led to reduce these two parameters.
The highest values of the essential oil percent were obtained from second level of salinity. Also, it was reported that salt stress had a significant effect on yield and percent of essential oil that was similar to our finding. This was reported that percent of essential oil in each plant and composition of essential oil changed. According to the results of this research, salinity treatment significantly increased essential oil percentage in Lavandula angustifulia.
Conclusion: The most important of leaf essential oil component is Borneol that was increased. So, the medium level of salinity stress caused to increase in percent and quality of lavender essential oil.
Kambiz Mashayekhi; Hossein Sadeghi; Vahid Akbarpour; Sadegh Atashi; Yousef Ghasemi; Seyyed Javad Mousavizadeh
Abstract
Carbohydrate flow between vegetative and reproductive parts of trees is one of the determining factors of yield and fruit quality. Therefore, it varies during different times of growth season. The aim of this study was to investigate the carbohydrate content variation during growth season between leaf ...
Read More
Carbohydrate flow between vegetative and reproductive parts of trees is one of the determining factors of yield and fruit quality. Therefore, it varies during different times of growth season. The aim of this study was to investigate the carbohydrate content variation during growth season between leaf and fruit of nectarine. So, eight nectarine trees cv. Red Gold selected randomly in the orchard and after labeling two of them combined and four replications achieved for laboratory tests. Results indicated that the highest fresh (9.3 g) and dry (3.3 g) weight of the leaves recorded at the last harvesting stage. Fresh to dry weight ratio showed a descending trend than can be indicated this fact that leaf biomass is low at primary harvesting stages and increased gradually. Chlorophyll a, b and ab reached to the highest content at the last harvesting stage. Total sugar content showed an ascending trend at second and third harvesting stages and decreased at final harvesting stage. Fruit chlorophyll content also decreased by maturation and fruit ripening; while, anthocyanin content showed an ascending trend. Fruit total sugar content decreased by third stage, two weeks after pit hardening, but increased at the final harvesting stage. Sucrose content variations show a higher value at primary stages of fruit growth in comparison with next stages and decreased by final stages. Total sugar increased at the fourth stage to third harvesting stage.
Kambiz Mashayekhi; Hossein Sadeghi; Vahid Akbarpour; Sadegh Atashi; Seyyed Javad Mousavizadeh; Malihe Abshaei; Zohre Nazari
Abstract
Citrus fruits contain numerous nutrients and secondary metabolites including sugars, vitamin C, flavonoids and phenols which have high antioxidant activity and nutritional value. Factors such as cultivar, type of stock and fruit position affect the amount of these compounds. Hence in this study the amount ...
Read More
Citrus fruits contain numerous nutrients and secondary metabolites including sugars, vitamin C, flavonoids and phenols which have high antioxidant activity and nutritional value. Factors such as cultivar, type of stock and fruit position affect the amount of these compounds. Hence in this study the amount of sucrose, glucose, total sugar, vitamin C, flavonoids and phenols in pulp, mesocarp and flavedo of Parson Brown and Mars oranges grafted on Citrange, Cleopatra and Rough Lemon stocks were measured. According to the results, maximum of vitamin C was in Parson Brown cultivar on the Citrange and Cleopatra grafting stocks. The highest total sugar was recorded in Parson Brown and Mars cultivars on the Rough Lemon stock (P