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African violet (Saintpaulia ionantha Wendl.) belonging to the family Gesneriaseae is a very popular indoor plant. The aim of this study was to investigate the effect of red, blue, red and blue light (one part blue and three parts red) and white fluorescent on the vegetative and reproductive growth of African violet plants. The experiment was conducted in a completely randomized design with 4 treatments and 16 replications in the first phase and 16 treatments with 4 replications in the second phase. The tallest plants in the first and second phases were those treated with red light with an average of 8.2 and 12.5 cm, respectively. Plants treated with mixed blue and red light produced the highest leaves/plant in the first phase of the experiment. However, these plants reduced their number of leaves in the second phase when treated with the blue light. In the first phase, the fluorescent and red light alone developed the greatest canopy area (about 350 cm2), while in the second phase, the canopy area in fluorescent light reached its maximum rate (500 cm2). Similar results were observed for the leaf area. Blue light produced the highest flowers/plant in the first phase, although in the second phase, plants transferred from fluorescent light to the mixed blue and red light indicated increases in flowers/plant. The overall results of the experiment indicate that the blue light plays an important role in early flowering and the red light has an important effect on the rate of canopy extension.

IntroductionVarious methods of stress directly affected the growth and production yield of numerous plants. For example, environmental stress reduces the tomato manufacturing by the disrupting its natural metabolism, or, salinity stresses affect the it is growth and development from the germination stage to the fruit ripening stage. Salinity in tomatoes by stimulating the biosynthesis of growth regulators such as ethylene and abscisic acid leads to the acceleration of the aging of the leaves. Therefore, development of different methods to induce salinity stress tolerance in plants is necessary. Some approaches were studied to develop the salinity tolerant plants such as genetic breeding, environmental improvements and usage of phytohormones and signal molecules. Salicylic acid or orthohydroxybenzoic acid plays an important role in regulating the physiological and biochemical responses of plants to stress conditions, which improves the plant's resistance to adverse environmental conditions. For instance, salicylic acid is a facile and effective way to increase plant productivity under salt stress conditions. Considering the positive effects of salicylic acid in modulating the effects of salinity, this study was conducted with the aim of investigating the effects of salicylic acid’s usage in modulating the harmful effects of salinity on some vegetative, physiological, quantitative and qualitative characteristics of two tomato cultivars of Baneh local mass and Semi Dwarf line.Materials and MethodsTo investigate the effect of salicylic acid in modulating the effects of salinity stress in tomato, a factorial experiment was conducted in the form of a randomized complete block design, with 12 treatments, in 3 replications and with a total of 36 experimental units in the hydroponic greenhouse of the Department of Horticulture, Faculty of Agriculture, and university of Tabriz. The treatments included two levels of salicylic acid (0 and 1 mM) and salinity levels (0, 35 and 70 mM NaCl) on two tomato cultivars of Baneh and Semi Dwarf.Results and DiscussionThe results showed that in Baneh and Semi Dwarf cultivars, the increase in salinity levels caused a decrease in vegetative indices, meanwhile the treatment of salicylic acid along with salt stress increased same indices. Also, salt stress caused yield reduction in both Baneh and Semi Dwarf cultivars. By examining the qualitative indicators, it was observed that titratable acidity and vitamin C increased with salt stress and salicylic acid treatment in both cultivars. In terms of physiological indicators, the amount of proline increased at different salinity levels with salicylic acid treatment, but the amount of leaf chlorophyll index decreased with the increase of same condition.ConclusionThe results of testing the effect of salicylic acid and the effects of salinity stress on vegetative, quantitative, qualitative and physiological indicators in Baneh and Semi Dwarf tomatoes showed a remarkable difference in terms of significance. In terms of vegetative traits; Plant height, leaf area index, shoot wet in Baneh and Semi Dwarf cultivars decreased with increasing salinity levels of vegetative indices, but salicylic acid treatment along with salinity stress increased same indices. Indicators such as yield, fresh weight of fruit, and percentage of dry matter of fruit showed different responses to different levels of salinity and salicylic acid treatment. The fresh weight of fruit increased with the application of salicylic acid. Also, salt stress caused an increase in the percentage of dry matter of the fruit. But salt stress caused yield reduction in both Baneh and Semi Dwarf cultivars. In terms of quality indicators; the amount of titratable acidity and vitamin C increased with salt stress and salicylic acid treatment in both cultivars. In terms of physiological indicators, the level of proline increased across various salinity levels with salicylic acid treatment. However, the leaf chlorophyll index decreased with rising salinity levels, even in the presence of salicylic acid treatment. Overall, salinity stress caused a decrease in most analyzed traits in the Baneh and Semi Dwarf cultivars. Nevertheless, it led to improvements in certain quality traits. Additionally, salicylic acid treatment enhanced the mentioned indices in most of the examined traits in both cultivars. Therefore, considering the positive effects of salicylic acid treatment on Baneh and Semi Dwarf cultivars under salinity stress conditions, its use is recommended.

Introduction Medicinal plants have long had a special role in the traditional ‎agricultural system of Iran and the use of these plants as medicine to prevent and treat diseases has been considered by ‎traditional medicine experts since ancient times. Medicinal plants with rich sources of secondary metabolites provide the ‎basic active ingredients of many medicines. Although the biosynthesis of secondary metabolites is genetically controlled, ‎but their construction is strongly influenced by environmental factors. One of the important climatic factors that affect the ‎distribution of plants around the world and can cause morphological, physiological and biochemical changes in the plant is ‎the lack of available water. Basil seems to show little resistance to water stress. For this reason, there is a need for protective mechanisms for the ‎basil plant against stress due to water shortage. Plants are able to reduce or eliminate the effects of water shortage ‎stress by coexisting with a number of soil microorganisms. Inoculation of the plants with Arbuscular mycorrhizal fungi (AMF) has been exploited as an applicable strategy for reducing detrimental effects of water deficit stress. Present study was performed to evaluate the effects of three AMF on some physiological responses of Ocimum basilicum under water deficit stress. Materials and Methods The pot experiments were conducted as factorial based on completely randomized design blocks with three replications. The experimental factors were three AMF namely Glomus etunicatum, Glomus mosseae and Glomus intraradices and various soil moisture including severe stress, moderate stress, mild stress. Water stress was applied from the beginning to the end of flowering stage. After flowering stage, plants ‎were harvested and traits such as total phenols and flavonoids, antioxidant ‎capacity (DPPH), malondialdehyde (MDA), catalase and peroxidase enzymes were measured. To analyze the data, first the test of data normality and uniformity of variance within the treatment was performed and confirmed. The mean of treatments was compared by Duncan test at the level of 5% probability. SAS software (Ver. 9.3) was used to analyze the data and Excel software was used to draw the graphs. Results and Discussion The results of analysis of variance of the effect of mycorrhiza fungus and soil moisture on the studied parameters show that the effect of different levels of soil moisture on all traits was significant. The results of analysis of variance also showed that the effect of mycorrhiza on phenol and total flavonoids, antioxidant activity, catalase and peroxidase and malondialdehyde was significant at the level of one percent probability. According to the results of analysis of variance, the interaction effect of mycorrhiza on soil moisture on antioxidant activity was significant at 5% probability level and on total phenols and flavonoids, malondialdehyde, catalase and peroxidase at 1% probability level. Results showed that AMFs improve activity of catalase and peroxidase, antioxidant capacity and total phenols which led to decrease malondialdehyde content. Antioxidants as physiologically active compounds play an important role in plant resistance to stress. Increased oxygen species due to dehydration stress are a warning sign for plants and increase the activity of antioxidant enzymes. The plant's defense system increases the production of antioxidant enzymes to neutralize toxic oxygen forms, and fungi improve the intensity of this increase, which may be due to the chemical structure of the metal isoenzymes copper, zinc, and manganese. Factors sent to make antioxidant enzymes also contain the elements zinc and calcium. Mycorrhizal fungi increase the absorption of nutrients by sending more hormonal factors and increasing the activity of enzymes, all of which can be effective in increasing the activity of antioxidant enzymes. Conclusion When plants are exposed to dehydration stress, reactive oxygen species in them increase. The expression of antioxidant genes and the activity of antioxidants to eliminate reactive oxygen species are increased and the antioxidant defense system is improved and the tolerance to dehydration stress in the plant is increased. Scientists believe that peroxidase is involved in metabolic processes such as hormone catabolism, defense against pathogens, phenol oxidation, binding to cell structural proteins and cell wall polysaccharides. Present study revealed that application of AMFs can be good strategy for reducing harmful effects of water deficit stress in plants. Research has also shown that impregnating seeds with mycorrhiza increases antioxidants and reduces the amount of reactive oxygen species, a characteristic of resistance induction that occurs by this antagonist. ‎ ‎

The small date moth Batrachedra amydraula Meyrick (Lepidoptera: Batrachedridae) and other date palm moths are among the most important date fruit pests, causing the date fruits to dry and fall. This study aimed to investigate the relationship between the density of B. amydraula population and the extent of its injury level as well as between the rate of damage and reduction of date yield indices on six commercial date palm cultivars in five provinces of Iran including Khuzestan, Bushehr, Hormozgan, Kerman and Saystan & Baluchestan durying 2018 and 2019. Production management costs in both chemical and biological control approaches were considered. Also, crop prices in each region were calculated based on a six-month average prediction. Sampling were done at 15-days intervals from May to early September. To this end, four clusters were selected from four different geographical directions of each tree and in each cluster, 25 fruits were checked to determine the number of healthy and infested fruits. Finally, the Norton model was used to calculate EIL under biological and chemical control conditions. Based on the results, the cost of biological control was lower than that of chemical control. The highest cost in both methods was the cost of purchasing the controlling materials. The highest rate of injury (symptoms of nutrition) to the crop was observed in Mazafati cultivar and the lowest one was in Kabkab. Also, the highest crop damage (nutrition losses) caused by pest damage unit was observed in Rabi cultivar and the lowest one was in Kabkab cultivar. In all studied cultivars, the economic injury level in 2018 was lower than 2019 in both chemical and biological control methods. On the other hand, in biological control method in both years and on all cultivars, costs were lower than chemical control method. The highest value of economic injury level in 2019 was estimated for cultivar Sayer in biological control method (1546.1 larva-day) and the lowest one was estimated for cultivar Rabi in chemical control method (13.81 larva-day).

In order to evaluate the forage quantity and quality of Sorghum in intercropping with soybean, a field experiment was carried out as a factorial based on a randomized complete block design (RCBD) with three replications at the Faculty of Agriculture, University of Maragheh, during the 2016 growing season. The first factor included different planting patterns with eight levels (soybean monocultures with densities of 40 and 50 plants m-2, sorghum monocultures with densities of 10 and 15 plants m-2, and intercropping of the two plant species with the mentioned densities); the second factor consisted of two levels of inoculation with nitroxin (Azotobacter chroococcum and Azospirillum brasilense) Bio-fertilizers and Phosphate solubilizing bacteria (Pseudomonas flurescence) and non-inoculation. The results showed that the highest (25.59 tons ha-1) and lowest total dry forage yield was obtained in intercropping soybean (with densities of 40 and 50 plants m-2) + sorghum (15 plants m-2) with inoculation and soybean monocultures (with densities of 40 and 50 plants m-2) without inoculation, respectively. Also, the highest and lowest values of forage ash, digestible dry matter (DDM) and net energy of lactation (NEL) were obtained in intercropping soybean (50 plants m-2) + sorghum (10 plants m-2) and monoculture of sorghum (15 plants m-2), respectively. The highest content of the acid detergent fiber (ADF) and neutral detergent fiber (NDF) was obtained in the monoculture of sorghum (15 plants m-2) without inoculation. In addition, application of bio-fertilizer increased the content of crude protein (CP), DDM, dry matter intake (DMI) and NEL by 6.29, 1.71, 3.29 and 2.72%, respectively, as compared to the control. Also, the highest land equivalent ratio and monetary advantage intercropping (MAI) were achieved in the intercropping of soybean (50 plants m-2) + sorghum (15 plants m-2). Generally, intercropping of soybean (50 plants m-2) + sorghum (15 plants m-2) and soybean (50 plants m-2) + sorghum (10 plants m-2) could be introduced as the best treatment in terms of forage quantity and quality, respectively.

Aeolian erosion is a serious environmental threat that damages soils. Dust storms are one example of the consequences of aeolian erosion in dry and semi-arid areas across the world. In this regard, soil surface roughness is an important parameter for monitoring climate changes on the Earth and modelling aeolian erosion. Synthetic Aperture Radar (SAR) systems are valuable resources for estimating soil surface roughness. In arid soils, SAR backscatter is sensitive to the soil surface roughness at higher frequencies and higher incident angles. Based on these facts and lack of studies in the field of dust and erosion using remote sensing methods, an Artificial Neural Network (ANN) along with Sentinel-1 images in two polarizations (VV and VH) were initially applied to estimate surface roughness for the first time in Bandar-e Emam-Omidiye, Khuzestan, Iran. Subsequently, the results were used to investigate potential dust sources. The parameters used to train the ANN included the radar backscatter coefficient, incident angle, and in-situ roughness. The training accuracy of the proposed ANN was relatively high with an RMSE of 0.8821 and RMSE = 0.8804 for VH and VV polarizations respectively. These data were subsequently used to identify areas prone to dust. The results obtained from the investigation of 25 stations located in areas with five different land covers indicated accurately that locals on clay flats (RMSE = 1.08) are the most prone to aeolian erosion in the form of dust.

Land cover classification is important for various environmental assessments. The opportunity of imaging the Earth’s surface makes remote sensing techniques efficient approaches for land cover classification. The only country-wide land cover map of Iran was produced by the Iranian Space Agency (ISA) using low spatial resolution Moderate Resolution Imaging Spectroradiometer (MODIS) imagery and a basic classification method. Thus, it is necessary to produce a more accurate map using advanced remote sensing and machine learning techniques. In this study, multi-temporal Landsat-8 data (1,321 images) were inserted into a Random Forest (RF) algorithm to classify the land cover of the entire country into 13 categories. To this end, all steps, including pre-processing, classification, and accuracy assessment were implemented in the Google Earth Engine (GEE) platform. The overall classification accuracy and Kappa Coefficient obtained from the Iran-wide map were 74% and 0.71, respectively, indicating the high potential of the proposed method for large-scale land cover mapping.

In order to evaluate the effect of biofertilizers (nitroxin and phosphate barvar2), vermicompost and chemical fertilizers on the quantity and quality traits of sugar beet (Beta vulgaris L.), an experiment was conducted in randomized complete block design (RCBD) with 13 treatments and three replications at Agricultural and Natural Resources Research Station of Miandoab, Iran in 2015. The treatments were 100% chemical fertilizer (350, 100 and 50 kg ha-1 urea, superphosphate triple and potassium solphate) as control (T1), 10 t ha-1 vermicompost (T2), 20 t ha-1 vermicompost (T3), 10 t ha-1 vermicompost + 50% chemical fertilizer (T4), 20 t ha-1 vermicompost + 50% chemical fertilizer (T5), nitroxin + phosphate barvar 2 (T6), 10 t ha-1 vermicompost + nitroxin + phosphate barvar2 (T7), 20 t ha-1 vermicompost + nitroxin + phosphate barvar2 (T8), nitroxin + phosphate barvar2+ 50% chemical fertilizer (T9), 10 t ha-1 vermicompost + chemical fertilizer (196 and 85 kg ha-1 urea and superphosphate triple) (T10), 20 t ha-1 vermicompost + chemical fertilizer (40 and 70 kg ha-1 urea and superphosphate triple) (T11), nitroxin + phosphate barvar 2 + 10 t ha-1 vermicompost + 50% chemical fertilizer (T12) and nitroxin + phosphate barvar2 + 20 t ha-1 vermicompost + 50% chemical fertilizer (T13). The highest (47.8) and lowest (39.2) chlorophyll indices were obtained in T13 and T2 treatments, respectively. Also, the highest root yield (66366 kg ha-1) was achieved in T13 treatment that was not significantly different from T12 and T11. Due to a combination of organic and biological amendments with chemical fertilizers, sugar yield was increased significantly in T13 treatment due to increases in root yield and sugar content. The sugar yield and white sugar yield in T13 treatment increased 16.7% and 23.5%, respectively compared with T1. Generally, based on root yield, white sugar yield and extraction coefficient of sugar, integrated application of nitroxin + phosphate barvar2 + 20 t ha-1 vermicompost + 50% chemical fertilizer can be recommended for sugar beet production in the Miandoab area.

Mites are the best representative of soil arthropods because they are the most diverse in terms of ecological niche and behavior. In this study, abundance and biodiversity of laelapid soil mites were evaluated in eight sites in Saman and Shahrekord, with each site including an orchard and a farmland. There was a significant difference in the Shannon-Wiener diversity index of laelapid mites among different land uses. The maximum value of this index was (0.44) in soil of elm trees in Shahrekord. The Margalef species richness index was highest (0.64) in an almond orchard in Saman. The maximum amount of the Simpson index was (0.39) in the almond orchard of Saman. The regression line equations and coefficient of determination between the soil organic matter and biodiversity indices were calculated. The results showed that the coefficient of determination (r2= 0.73) for soil organic matter and the Simpson index was higher than that of other indices. Therefore, it could be concluded that the response of laelapid soil mites conforms to the management practices of farmlands, changes in abundance of species, and biodiversity indices.

We experimentally studied intense femtosecond pulse filamentation and propagation in water for Bessel-Gaussian beams with different numbers of radial modal lobes. The transverse modes of the incident Bessel-Gaussian beam were created from a Gaussian beam of a Ti:sapphire laser system by using computer generated hologram techniques. We found that filament propagation length increased with increasing number of lobes under the conditions of the same peak intensity, pulse duration, and the size of the central peak of the incident beam, suggesting that the radial modal lobes may serve as an energy reservoir for the filaments formed by the central intensity peak.

To evaluate the effects of different irrigation levels and foliar application of nutrients, on dry matter yield and essential oil content and composition of peppermint (Mentha piperita L.), a field experiment was conducted as a split plot based on a randomized complete block design, with 12 treatments and three replications, at the faculty of Agriculture, University of Maragheh, Iran in 2021. The factors included irrigation as the main factor at three levels (irrigation after 20 (control), 40 (moderate stress), and 60% (severe stress) of the maximum allowable moisture depletion) and fertilizer source as the sub-factor at four levels (non-application of fertilizer (control), and foliar application of Macromix gold, Ecoquel micromix, and Vitalem forte). The results demonstrated that the highest (280.5 g.m-2) and lowest (113.7 g.m-2) total dry weight were obtained under normal irrigation conditions (control) with the application of Macromix gold and severe stress without fertilizer application, respectively. Total dry weight decreased by 22.7 and 40.3% under moderate and severe drought stress conditions, respectively compared to normal irrigation. Macromix gold, Vitalem forte, and Ecoquel micromix application enhanced the amount of total dry weight by 37.7, 23.8, and 17.1% compared to no fertilizer application, respectively. The highest content (2.1%) and essential oil yield (4.5 g.m-2) and also the highest amount of menthol (40.9%), menthone (28.1%), and cineole (6.2%) in the essential oil were observerd under moderate water stress conditions fertilized with Macromix gold. Based on the obtained results, the foliar application of Macromix gold could be recommended as an effective solution to enhance the quantity and quality of the peppermint essential oil under drought stress conditions. [ABSTRACT FROM AUTHOR]

This study describes the use of duck bone gelatin in a taro starch mixture to produce biodegradable films. Films were produced using duck bone gelatin in various percentages (0%, 5%, 15%, 25%, and 35% of the total solid weight) and added with glycerol as a plasticizer and the solution casting method. Parameters observed were tensile strength, percent elongation, thickness, moisture content, and surface morphology of the product was observed by scanning electron microscopy (SEM) analysis. Adding duck bone gelatin to biodegradable films based on taro starch had a significant effect (p0.05) on thickness. The biodegradable film with a 5% duck bone gelatin concentration produced the highest tensile strength of 11.333 MPa and the highest percent elongation of 17.100%. Thickness values for all additions of duck bone gelatin concentration ranged from 0.191 to 0.194 mm, and the highest moisture content produced at 35% duck bone gelatin concentration was 4.079%. The surface morphology of the biodegradable film with a 5% duck bone gelatin concentration with the highest tensile strength value shows a flat, solid but slightly rough cross-section which may be caused by the flexibility of the gelatin film.