فهرست مطالب علیرضا شایگانفر

The increase in the production and consumption of grapes in the world has increased the need for research in the field of creating conditions for further preservation of this fruit, and the lack of sensors that can provide accurate information from the production and storage process to control systems for decision-making is obvious and evident. Therefore, this study aimed to determine some characteristics of grape fruit (taste index, pH, firmness, ion leakage, ∆E, number of mold and general acceptance) stored in cold storage in the range of storage time from 0 to 60 days was measured and according to the importance Achieving these characteristics during fruit storage, a model using fuzzy logic was created as an expert system with accuracy (with a correlation coefficient greater than 0.96) and very high speed capable of predicting and determining these product characteristics only by using It was time to save it. This system was able to obtain the value of each of these studied characteristics at any desired storage time in the range of 0 to 60 days with very high accuracy and in a fraction of a second. On the other hand, it was found that with increasing storage time, the amount of taste index, pH, number of molds, ∆E and ionic leakage of the samples increased, but the degree of hardness and overall acceptance decreased.

Nowdays, because of human industrial activities, ozone layer depletion increases the amount of ultraviolet (UV) irradiation that reaches Earth’s surface; creating problems for living organisms. Since plants always need sunlight, the effects of UV radiation on plants are inescapable. The present study was conducted to evaluate the physiological, phytochemical and chlorophyll fluorescence responses and stomatal characteristics of three cornflower cultivars to UV radition in 2018.

The experiment was performed as a split plot in a completely randomized design. Ultraviolet light was considered as the first factor in four levels (control, ultraviolet A, ultraviolet B and ultraviolet A + B) and three cornflower cultivars as the second factor. When seedlings had four real leaves, the UV treatments were started by ultraviolet lamps made by Q-Lab company of the USA. At the end of experiment, physiological and phytochemichal traits including relative water content, electrolyte leakage, lipid peroxidation, chlorophyll a and b, carotenoid content, catalase and peroxidase activity, stomatal gurad cell length and width, stomatal index, stomatal density, chlorophyll fluorescence, phenol and flavonoid contents, anthocyanin, and antioxidant activity of extract were assayed. The analysis of variance was done using Minitab software according to the experimental desing. Mean comparison was performed using LSD test method at 0.05.

The results showed that the amount of malondialdehyde, electrolyte leakage and antioxidant enzymes activity was increased under UV-B radiation. UV-B radiation decreased leaf chlorophyll content, but increased carotenoids. UV A had no significant effect on chlorophyll, while, increased carotenoids. Maximum fluorescence, variable fluorescence and maximum quantum efficiency of photosystem ІІ were reduced under UV treatment. In contrast, UV radiation increased the minimum of fluorescence. UV-B and UV-A+B radiation increased width of stomatal gurad cell, and stomatal index and density, but decreased length of stomatal gurad cell in cornflower. The amount of flavonoids, total phenol, anthocyanin and antioxidant activity of cornflowers increased by UV radiation. Among the cornflower cultivars studied, Kornblume blau cultivar had shown the highest values of total phenol, total flavonoids and anthocyanins as well as antioxidant activity.

In the present study, UV-B radiation and simultaneous UV-A+B radiation led to more extensive physiological and phytochemical responses in cornflower cultivars. Based on the results obtained in this study, it can be concluded that UV-B has more destructive effects than UV-A on cornflower. In the comparison between cultivars, it was found that Kornblume blau cultivar is more suitable for medicinal use due to its higher phytochemical compounds and biological activity.

In this research, due to the lack of a study on the modeling of the storage conditions of grape fruits coated with maltodextrin containing potassium nanocarbonate and pyracantha extract using the fuzzy-neural inference system (ANFIS), different storage times (zero to 60 days), concentration Potassium nanocarbonate (zero to 2%) and concentration of pyracantha extract (zero to 1.5%) used in edible coating as input and the amount of Brix, the percentage of dropping berry, the amount of malondialdehyde, the browning of the grapes cluster, aroma and taste of samples were considered as output. Three Gaussian, triangular and trapezoidal membership functions with 2-2-2 and 3-3-3 membership functions were investigated. The results showed that trapezoidal function with 3-3 membership function and Gaussian function with 3-3 membership function were selected as the best model for Brix output variable and percentage of dropping berry, respectively. finally, triangular model with 3-3 membership function was selected for cluster browning and malondialdehyde variables. On the other hand, the results indicated that with the increase in storage time, the amount of Brix, the percentage of dropping berry, malondialdehyde and cluster browning increased in all samples, but the amount of aroma and tast of the samples decreased. the use of coating containing potassium nanocarbonate and pyracantha extract caused the speed of these changes to decrease. In the end, it can be said that the high correlation coefficients between the laboratory results and the model outputs indicate the acceptable accuracy and usability of these models in controlling the storage conditions of grape fruits coated with maltodextrin containing potassium nanocarbonate and pyracantha extract.

Hymenocrater longiflorus Benth. belongs to the Lamiaceae family, is a medicinal and aromatic plant native to Iran. The antimicrobial, antifungal and antioxidant properties of this plant have been proven and its aerial part is used in the treatment of skin diseases. In this study, the aerial part of this plant was collected from its natural habitat and then the essential oils of different organs (leaf, flower and stem) were extracted by water distillation method using a clevenger apparatus. The essential oils were analyzed using GC/MS and GC/FID. The results indicated that the essential oil content of leaves (0.4%) was much higher than flowers (0.2%) and stems (0.2%). In all three organs, sesquiterpenes formed the major part of the essential oil. The highest amount of monoterpene hydrocarbons (20.11%), oxygenated monoterpenes (17.36%), sesquiterpene hydrocarbons (50.69%) and oxygenated sesquiterpenes (27.89%) were observed in the essential oils of stem, leaf, flower and stem organs, respectively. The dominant components of leaf essential oil were β-elemol, bicyclosesquiphellandrene, α-pinene and 1,8-cineole, respectively. Bicyclosesquiphellandrene, β-elemol, β-calarene and linalool were as the major components of flower essential oil. The main constituents of stem essential oil were β-elemol, bicyclosesquiphellandrene, α-pinene and sabinene, respectively. The observed diversity in the essential oil content and composition of different organs of Hymenocrater longiflorus Benth. can be useful for identify and exploit the desired genotypes in order to domestication, cultivation and breeding of this plant.

Rose-scented geranium (Pelargonium graveolens Lchr('39')Heritier) is an important ornamental plant that is cultivated worldwide due to its valuable medicinal properties. The present research was conducted to evaluate the effect of light intensity and UV radiation on the morphological and physiological characteristics of rose-scented geranium in 2020. The experiment was performed as split plots in a completely randomized design. Light intensity was considered as the first factor at two levels (low light intensity and high light intensity) and ultraviolet radiation at four levels (environmental UV, UV-A, UV-B and UVA+B) as the second factor. The results showed that high light intensity reduced petiole length, leaf length and width and plant height of P. graveolens; in contrast, the number of lateral branches and stem diameter were increased by rising light intensity. UV-B and UVA+B reduced plant height, petiole length and leaf length and width; but, the number of lateral branches and stem diameter were increased by UVB treatments and UVA+B treatments. While, plant produced leaves and branches with elongated shapes when traeted by UVA and environmental UV. In terms of physiological traits, results showed that increasing the light intensity reduced the relative water content of leaf, intercellular CO2 and stomata conductivity. In contrast, chlorophyll a, chlorophyll b, total chlorophyll, transpiration, electrolyte leakage, catalase activity and photosynthesis rate were increased by increasing light intensity. Also, UVB and UVA+B treatments led to reduce chlorophyll a, chlorophyll b, total chlorophyll and photosynthesis rate. Under high light intensity, UVB and UVA+B reduced the stomata conductivity. The amount of electrolyte leakage, malondialdehyde, intercellular CO2 and the activity of catalase and peroxidase enzymes were increased by UVB and UVA+B radiations. Althogh, the rate of increase of these traits by UVB and UVA+B was more severe in low light intensity.

Increase in ultraviolet radiation (UV (, especially UV B, as one of the consequences of climate change, can disrupt the growth of plants. UV light influences plant growth and metabolism. Various studies have shown that increasing in UV B can have detrimental effects on physiological processes and overall growth of some plants. The use of exogenous plant growth regulators has mostly been effective in reducing the effects of environmental stresses in plants. The present study was conducted to investigate the effect of UV-A and UV-B and foliar application of melatonin and ascorbic acid (ASC) on growth, biomass and morphological and stomatal characteristics of fenugreek in 2019.

The experiment was performed as a split plot in a completely randomized design in the research greenhouses of the Faculty of Agriculture and Natural Resources, Lorestan University. Ultraviolet radiation was considered in four levels as the first factor (including: control, UV-A, UV-B and UV-A+UV-B) and application of osmolytes was used in four levels (Control, melatonin, ASC and melatonin+ ASC) as the second factor. Finally, Plant height, plant width, number of leaves, leaflet length and width, petiole length, crown diameter, plant fresh weight, plant dry weight, leaf fresh weight, number of internodes, number of lateral branches, stomatal gurad cell length and width, stomatal index, stomatal density, chlorophyll and carotenoid contents were measured. The data obtained from the experiment was analyzed using Minitab software. Mean comparison was performed using LSD test method at 0.05.

The results showed that UV-A increased fresh leaf weight, crown diameter, leafstalk length, leaflet length and width, plant height and width, plant fresh weight (12.17%), plant dry weight, number of internodes and content of chlorophyll a (7.4%) and chlorophyll b (3.5%), but reduced the number of lateral branches (15.63%). In contrast, UV-B and UVA+UVB treatments reduced most of the studied traits including plant height (8.09%), leaflet length and width, leafstalk length, chlorophyll a, chlorophyll b, total chlorophyll, plant fresh and dry weight and leaf fresh weight. However, carotenoid content, the number of lateral branches (6.58%) and stomatal index (11.4%) were increased by UV-B and UV-A+UV-B. Application of ASC and melatonin reduced the negative effects of UV-B on fenugreek. In control and UV-A treatments, ASC foliar application had shown the best effects on the studied traits and the highest plant height, number of lateral branches, number of leaves, leaf length and width, chlorophyll, carotenoids, and stomatal index and density were observed in this treatment. While, simultantious application of melatonin and ASC led to the best results under UV-B and UVA+B treatments. Therefore, it can be concluded that the synergistic effect of these two compounds in modulating the effects of ultraviolet stress on fenugreek was remarkable.

In the present study, UV-B radiation and simultaneous radiation of UV-A and UV-B reduced the growth and development of fenugreek. In contrast, UV-A treatment improved yield and morphological characteristics of the plant. In addition, foliar application of melatonin and ascorbic acid modulated morphological destruction and growth indices caused by ultraviolet-B treatment.

In the last decades, human activities have had adverse effects on the atmosphere and the stratospheric ozone layer, resulting in an increase in the ultraviolet radiation on the ground, especially in highlands. Among living organisms, plants are the most exposed to ultraviolet rays due to their high and unavoidable need to light for photosynthesis, and are therefore more vulnerable to them. Plants show different responses to ambient UV radiation. The response of plants to ultraviolet light is manifested in two general ways, including tolerating the destructive effects of this radiation or/and avoiding it. The present study was conducted to evaluate the effect of ultraviolet light on growth, morphological and phenological characteristics of three cornflower cultivars under greenhouse conditions in 2018.

The experiment was performed as a split plot in a completely randomized design. Ultraviolet light was considered as the first factor in four levels (including: control, ultraviolet –A radiation, ultraviolet -B radiation and ultraviolet A + B radiations) and three cornflower cultivars (including: ‘Kornblume pink’, ‘Kornblume rot’ and ‘Kornblume blau’) as the second factor. The UV treatment was applied by lamps made by Q-Lab Co, USA. It should be noted that the 40-watt lamps used in this study were broadband and had the highest compliance with ultraviolet B (in the case of UV-B lamps) and ultraviolet A (in the case of UV-A lamps) received from the sun on the ground. So they provided the best possible simulation. During the growth period of plants, phenological traits were recorded and morphological traits and biomass traits were measured at the end of the experiment.

The results showed that UV-B radiation and simultaneous application of UV-A and UV-B radiations resulted in the reduction of the most morphological traits and yield traits including plant height, internode length, leaf width, leaf area, flowering stem length, plant fresh and dry weight, leaf dry weight, flower dry weight and number of flowers. However, flower yield was not affected by ultraviolet radiations. UV-A treatment reduced the flowering stem length and fresh and dry weight of plant in compared to the control treatment, but it had no significant effect on plant height, leaf width, leaf dry weight, flower dry weight and number of flowers. Plants response to ultraviolet radiation is very different. In many species, it has been observed that UV-A does not have a negative effect on plant growth, while, UV-B reduced the growth and yield of plants. It seems that the main reason for the reduction of plant growth and production is prevention of cell division caused by ultraviolet radiation. Degradation of plant pigments (chlorophyll) is also one of the main reason of photosynthesis decrease led to plant growth and yield reduction. The results of the present study showed that the application of UV-A reduced the number of days until the emersion of the first flower bud and the number of days until the opening of the first flower in cornflower cultivars compared to the control. UV-B treatment forced cornflowers to earlier flowering than UV-A. However, the fastest entry into the reproductive and flowering phase of cornflower cultivars was observed with the simultaneous application of UV-A and B radiations. Plants mechanisms against environmental stresses mainly depend on their origin and genetic factors. These mechanisms include three main strategies including “avoidance”, “tolerance” and “escaping”. One of the most important ways to reduce the life cycle is early flowering. It seems that the process of early flowering and completing the growth in cornflower species is a kind of stress escaping under ultraviolet radiation stress.

In this study, ultraviolet radiation reduced the growth and development of all three species of cornflowers. However, UV-A treatment showed the least negative effect on flower yield of plants. On the contrary, UV-B radiation and simultaneous application of UV-A and UV-B radiations reduced the growth and development of cornflowers, but did not have any significant negative effect on the flower yield (as the main useable organ of plant). Therefore, it seems that the ultraviolet radiation can be considered as a positive factor due to its positive effects on the production of secondary metabolites and early flowering and lack of significant negative effects on plant flower yield. Finally, ‘Kornblume pink’ cultivar, with higher flower yield and earlier flowering, is more suitable for cultivation than other cultivars.