فصلنامه پژوهش های تولید گیاهی
سال بیست و هشتم شماره 3 (پاییز 1400)

Oilseed crops have an effective role in nutrition and industry. Flax (Linum usitatissimum) seeds contain approximately 30 to 40 percent of oil rich in unsaturated fatty acids, especially linolenic acid. Previous studies in flax had showed significant positive correlation of seed yield with number of branches per plant, number of capsules per plant and 100 seed weight. It had reported that the number of capsules per plant is the most important selection criteria for genetic improvement of seed yield in flax. The present study was conducted to investigate relationship between seed yield and its related traits in breeding lines derived from KO37× SE65 cross using correlation, regression and path analysis to determine the best indirect selection criteria for genetic improvement of seed yield in flax.

In order to study the relationships between traits, 112 breeding lines along with six genotypes as control (including parental genotypes) were evaluated in augmented experiment design. Genotypes were planted in a randomized complete block design with 3 replications. Morphological, phonological and agronomic traits such as number of days to 50% flowering, end of flowering, period of flowering, number of branches per plant, number of capsule per plant, biological yield, and seed yield per plant were measured and analyzed using SAS software(Version, 9.1).

Number of capsule per plant, number of branches per plant, seed weight per capsule and biological yield per plant were positively correlated with seed yield per plant. Based on the results of stepwise regression analysis, number of capsule per plant could enter to the model in the first step and accounted 78% of the total variation. Seed weight per capsule and the number of branches per plant were entered in the subsequent steps and could explain the 86.87% of total variation. Path analysis results indicated that number of capsule per plant had the most direct effect on seed yield per plant, whereas, number of branches per plant had the most indirect effect through number of capsule per plant. Number of capsule per plant was recognized as the most important component explaining seed yield variation in the studied population. Four factors explained the most of variation of studied traits and could explain more than 68% of the total variation.

According to the results, number of capsule per plant had the most impact on seed yield variation and also there was no significant negative correlation between this trait and other seed yield components. Therefore, number of capsule per plant can be used as an indirect selection criteria for genetic improvement of seed yield in flax.

Khuzestan province is one of the suitable region for off-seasion production. In this region potato was planted crop from mid November to mid January. Analyses of meteorological data showed that the probability of a frost occurrence is 50% from late December to late February. Therefore potato plants of different planting dates are often subjected to frost in various phonological stages, so that, yield loss will vary depending on the planting date. In fact, this experiment was conducted to evaluate the effects of planting date on yield and agronomic characteristics of potato cultivars, but frost occurrence in mid January created exceptions and special opportunity for us to study the influence of frost occurrence in different phonological stages on recovery rates and some growth indices of potato cultivars.

This study was conducted on the research farm of Behbahan Agriculture Research Station from 2015 to 2016. This research was done in a split plot experiment arranged in a randomized complete block design with three replications. Planting date considered as the main plot, from 1 to to 21 December with 10 day intervals and four cultivars as sub plot (Sante, Savalan, Santana and Almera). five plants were sampled from each sub-plot from 15 days after plants emergence to harvest with 15 days interval and separated into haulms and tubers. Plant tissue was oven dried at 75ºC for 72 hours. The growth indices including haulm growth rate, tuber growth rate, crop growth rare and relative growth rate growth calculated. When the diameter of the swollen tip of stolon was twice as long as stolon diameter, considered as tuber initiation . Tubers were harvested in mid May. After harvest analysis of variance were done by MATAT-C statistical software and means were compared using Duncan’s multiple test range.

When frost occurred, the phonological stages of plants in planting dates of 1 and 11 Dec. were vegetative growth and tuberization stages respectively, so that all haulms were killed, while plants in planting date of 21 Dec. didn’t emergence from soil. The yield of 11 Dec. planting date was significantly higher than 1 Dec at 5% probability level. Haulm growth, crop growth rate and relative growth rate of all cultivars were negative during the first sampling period after frost occurrence. The recovery rate of Savalan cultivar was higher as compared with other cultivars. Due to higher tuber and crop growth rate, Savalan cultivar produced the highest yield in 1 and 11 Dec. The maximum relative growth rate in planting dates of 1 and 11 Dec. were recorded for Sante and Savalan cultivars respectively. The yield of 21 Dec. planting date was significantly higher than1 and 11 Dec at 1% probability level.

The findings of this study suggest that to minimize the risk of yield loss by frost, planting of potato should be avoided before late January in Khuzestan province and Savalan cultivar is recommended for this area.

Iran has the world's agricultural industry is a valuable product pistachios (Pistacia vera L) and the products economically one of the most important horticultural crops in Iran. Various stresses particularly drought, pistachio cultivation has always faced a lot of difficulties and obstacles to the extent that in some provinces faced with significant challenges. Breeding processes including control crossings to increase resistance, can be safe and permanent solution for reducing the deleterious effects of drought stress on plants to be considered. Therefore, considering the importance of pistachio product in the country as a strategic product and as well as Iran's location in dry and semi-arid conditions, research in order to develop drought-tolerant hybrid is essential.

In this study, in order to investigate the effect of drought stress on the level of activity of some antioxidant enzymes and some growth characteristics pistachio seedlings and identification of tolerant rootstocks, this experiment was designed. The experiment was conducted as factorial based on a Completely Randomized Design with four replications in the research greenhouse of Gorgan University of Agricultural Sciences and Natural Resources during 2018-2019. The treatments were consisted of five pistachio rootstocks Ahmad Aghaei, Akbari, Sorkheh Hosseini, Garmeh, Fandoghi and five interspecific hybrids (Ahmad Aghaei × Integerrima, Akbari × Integerrima, Sorkheh Hosseini × Integerrima, Garmeh × Integerrima and Fandoghi × Integerrima) and three levels of drought including control (100 % field capacity), mild stress (65% of field capacity) and Severe stress (30% of field capacity) were applied on 3 months old the seedlings for 84 days.

According to the results, the effects of rootstock and drought and as well as their interaction on most of the studied traits were significant (P ≤0.01). However, no significant effect (P≥ 0.05) was observed on stem length in relation to rootstock and drought interaction. The results showed that with increasing levels of drought, the activity of catalase, peroxidase, ascorbate peroxidase, superoxide dismutase, guaiacol peroxidase, hydrogen peroxide in leaves and roots and also, the amount of leaf fall in the studied pistachio seedlings increased and the number of leaves, stem length and diameter decreased.increased in the studied seeds. The highest amount of enzyme activity was observed in severe drought treatment and the lowest amount was observed in control treatment. On the other hand, in relation to leaf number, length and stem diameter, the highest and lowest values were observed at the control level and severe stress, respectively. Based on the results, different physiological responses were observed between the seedlings in their response to water stress. Drought tolerant rootstocks Hydrogen peroxide content and lower leaf fall percentage and higher enzymatic and growth activity than drought-sensitive rootstocks. The highest Fandoghi rootstocks and the hybrid rootstocks of Sorkheh Hosseini × Integerrima, Ahmad Aghaei × Integerrima and Akbari × Integerrima showed the least increase in the amount of Hydrogen peroxide leaves and roots and leaf fall between the rootstocks. In connection with these traits the seedlings rootstocks of Ahmad Aghaei, Sorkheh Hosseini, Garmeh × Integerrima, Akbari, Garmeh and Fandoghi × Integerrima were ranked next in terms of drought tolerance, respectively.

Based on the results of the present study it seams roots stock of Sorkhe Hosseini × Integerrima, Ahmad Aghaei × Integerrima and Akbari × Integerrima could be as potential seedlings in deal with drought tolerant. These hybrids possibly owns as gene pool for breeding high-yielding cultivars in arid regions.

In Iran, One of the important goals of apricot breeding programs is to obtain new compatible cultivars with the suitable characteristics. Therefore, it is necessary to evaluate the compatibility of promising genotypes in different parts of the country before releasing. The aim of this study was to evaluate the adaptability and determine the quantitative and qualitative characteristics of 35 hybrid and genotypes obtained from the breeding programs in Khorasan Razavi Agricultural and Natural Resources Research and Education Center. Matherials and

In this project, 35 selected and promising apricot genotypes obtained at Sahand Horticultural Research Station during the past years through hybridization and selection from native genotypes were evaluated for experiment in 2017-2019. Genotypes were studied in a randomized complete block design with three replications. Measured factors included phenological, morphological and pomological traits. Also, correlations between traits and decomposition into main factors were performed.

The results showed that DM101 genotype was the earliest ripening and Jalil was the late ripening. Genotypes in terms of tree vegetative ability in three groups (strong, medium and weak), branching in three groups (high, medium and low), distribution of buds in trees in three groups (often on spur, often on annual branches, equally on spur and annual branches). Also, The studied genotypes were very different in terms of average fruit weight, so that, Shanli cultivar with 75.50 g and the AC311 with 14.90 g had the highest and lowest average weights, respectively. Genotypes also differed significantly in terms of yield, so that the highest yield (110 kg) was observed in genotype of AD735. The kernel bitterness of most varieties, except for the AD741 and AD546, were sweet. Fruit biochemical characteristics also showed significant changes among genotypes, so that the soluble solids variations ranged from 13.48% in AD650 to 21.95% in AC801 and HS515. Fruit weight had a positive correlation with stone weight (0.73) and kernel weight (0.26) and negative correlation with yield (-0.19) and the number of days from the full bloom to fruit ripening (-0.18). Soluble solids had a negative correlation at 5% level with total acid (-0.21) and a positive correlation with pH (0.40) at 1% level. The results of principal component analysis showed that PC1 factor with 29.44% of total changes expressing pomological characteristics, PC2 factor with 17.00% total changes indicating morphological characteristics, PC3 factor with 9.00% total changes indicating phenological traits and PC4 factor With 8.00% of the total changes, they indicated the chemical properties of the fruit. These four combinations accounted for about 64.94% of the total variation.

In general, Shanli cultivar was superior in fruit size, Jalil in late ripening, good fruit quality and drying ability and Parsi in terms of fruit quality, marketability and excellent colorabitliy are superior to other genotypes.

Increasing fruit yield and improving fruit size along with high dry matter percentage, is the main goal of kiwifruit growers in the worldwide. There are deferent techniques to access exportable fruit size with high dry matter content in kiwifruit including summer pruning, root pruning and flower and fruit thinning. Furthermore, trunk girdling and plant growth regulators such as Forchlorfenuron (CPPU) are widely used in modern kiwifruits orchards to increase fruit yield and quality.

In this study, the effect of vine trunk girdling at different times (spring, summer, autumn), CPPU (10 mg L-1 of active ingredients in water), combined effect of CPPU and summer girdling as compared to control (without girdling and CPPU treatments) on fruits quality of Hayward kiwifruit at harvest and the end of cold storage was evaluated in complete randomized block design in 1398. Fruits were harvested based on soluble solids index and fruit quality was measured immediately after harvest and after three months storage at 1o°C.

The results showed that the summer girdling with CPPU, CPPU alone and spring girdling increased 37.99, 32.19 and 22.11% of kiwifruit weight compared to control respectively. Application CPPU increased fruits weight, length and diameter, but decreased fruits dry matter percentage and the ratio of soluble solids content to titratable acidity (SSC/TA) the compared to control. No significant differences were found between CPPU treated fruits and control for fruit tissue firmness, soluble solids content at harvest time and after three months storage in cold storage. The summer trunk girdling together with CPPU spray increased fruit weight (38% as compared to control). In addition, this treatment showed the highest fruit dry matter percentage, soluble solids and SSC/TA at harvest time and the lowest fruit weight loss (0.66%) with the highest fruits tissue firmness (3.96 kg force) at the end of three months storage time. Summer girdling showed the highest fruit weight loss (2.54%) at the end of storage, while no significant difference was found between autumn and spring girdling treatments compared to the control.

Overall, the results showed that summer vine trunk girdling with CPPU spray not only improved kiwifruit size and yield but also improved fruit quality by increasing fruits dry matter percentage and soluble solids content. Such fruits showed the longer postharvest life as compared to control and other treatments. Therefore, it is recommended for improving fruit size and quality in Hayward kiwifruit, CPPU spray was applied with summer vine trunk girdling.

Quinoa (Chenopodium quinoa) is a like-cereal plant with high nutritional value and tolerant of abiotic stresses. Quinoa has recently been recommended by the Ministry of Agriculture-Jahad for cultivation in saline areas with limited water supply, but there are not many studies on the growth characteristics and nutritional needs of this plant in the country. Nanotechnology has made possiblity to use nutrients and reduces the cost of environmental protection. Salinity stress is one of the most important limitations of crop growth in arid and semiarid regions. Due to the importance of salinity stress, nano- fertilizer and quinoa plant, this experiment was conducted to investigate the effect of spraying different nano-fertilizers on leaf and seed nutrient concentrations and some physiological traits in quinoa under salinity stress.

This experiment was carried out as a factorial experiment based on completely randomized design with three replications in the research farm of Urmia University in the pot during 2017. The first factor was salinity stress (Lake Urmia water was used) at three levels (0, 16 and 32 dS /m) and the second factor was nano-fertilizers at five levels (calcium, silica, zinc, potassium and control (no foliar application). To determine the amount of potassium and sodium, first standard solutions of each of these elements were prepared and the concentration of the elements was read by the flame-photometer (Clinical pfp7 model) by flame diffusion method, first the standards and then the main samples. Measurements of calcium and zinc were also read by atomic absorption spectrometer (model AA-6300). Statistical analysis of data using SAS software Ver. 9.1 and MATATC were performed and the means were compared by LSD test at the level of 5%.

Results showed that salinity stress of 32 and 16 dS/m compared to control traits leaf calcium (56 and 53%), seed calcium (52 and 48), chlorophyll a (32 and 14%) and chlorophyll b (28, 12%) decreased respectively; but the amount of seed zinc content (45 and 36%), carotenoids (30 and 18%), proline (33 and 15%), soluble sugars (24 and 8%), seed sodium (20 and 19%) and leaf sodium (56 and 48%), increased respectively. Foliar application of nanofertilizers in comparison with the control increased the amount of seed calcium, seed zinc, chlorophyll a and b and proline content. The highest amount on leaf zinc (67.66 mg/kg) were obtained from the treatment without salinity and spraying with zinc nanofertilizer. Also, the highest amounts of seed potassium (1.95%) and leaf potassium (3.86%) were obtained under salinity stress of 16 dS/m and foliar application of calcium and potassium, respectively.

The findings of this study indicated that different levels of salinity stress caused negative effects on all traits affecting quinoa growth. The highest reduction in traits was observed in salinity stress of 32 dS/m. Spraying with nano-fertilizer via enhancing chlorophyll and proline content, seed zinc and calcium led to increase total dry weight and seed yield of quinoa. Therefore, to improve the yield of quinoa especially in salinity stress conditions, spraying of nano-fertilizers is suggested.

The majority of the country's oil consumption comes from foreign sources. Therefore, the development of oilseed crops is critical. Safflower has a special status among oilseed grains adapted to the country's conditions, and it is ecologically compatible with many agricultural lands in the country. Research has shown that planting date and plant density significantly affect the yield and yield components of crops. Over the past few years and in different Iran regions, several cultivars have been isolated from safflower, which may vary in response to planting date and plant density. Therefore, this study was conducted to study and determine the most suitable planting date and plant density for the advanced safflower cultivars and their effect on grain yield, forage, oil, and yield components in the Gonbad-e Kavus area.

This study was conducted with two separate factorial experiments (the first experiment on 30th of November and the second on 20th of December) in a randomized complete block design with four replications at the Agricultural and Natural Resources Research Station of Gonbad-e-Kavus in two seasons of 2013-14 and 2014-15. In each experiment, two sowing densities of 20 and 40 plants per square meter (10 and 20 cm plant distance on the row) and four advanced safflower cultivars included: Golmehr, Soffeh, Padideh, and Goldasht, were combined as factorial and formed eight treatments. Seeds of the mentioned cultivars were prepared from the Golestan Agricultural and Natural Resources Research and Education Center. The row spacing was fixed at 25 cm for all treatments. SAS software was used to analyze the data, and the mean comparison of the data with SPSS software was performed as the least significant difference (LSD) test.

The results showed that the effects of planting date on the branch number plant-1, grain yield, oil percentage, forage ash, and the dry matter intake were significant. The influences of sowing density on branch number plant-1, 1000-seed weight, and oil percentage were significant. There were significant differences among the cultivars according to the branch number plant-1, and safflower seed oil percentage. The mean comparison of data showed that the highest branch number plant-1, grain yield, forage ash, and the dry matter intake were observed in the first planting date, and the delayed sowing decreased these traits significantly, while oil percentage showed a significant increase. Increasing the sowing density induced the branch number plant-1, 1000-seed weight, and oil percentage significantly. The forage yield showed a positive significant with grain yield and crude protein.

In terms of safflower planting date, it was observed that the first planting, due to suitable climatic conditions and longer growing period, had better results in the branch number plant-1, boll number plant-1, oil content, forage ash, and dry matter intake traits. With increasing plant density, branch number plant-1, 100-seed weight, and oil percentage decreased significantly, so due to the importance of oil content, 20 plants per square meter is recommended. According to this study's results, the Soffeh cultivar could be used for the earlier sowings, but there was no significant difference in grain yield among the cultivars with delayed sowing. So, four studied cultivars Golmehr, Soffeh, Padideh, and Goldasht, could be cultivated under the delayed planting date conditions, and it is suggested that selection of safflower cultivar should be made according to the purposes of safflower planting (forage, oil, or seed breeding).

Although wood chip substrate has been reported as a suitable substrate for growing shiitake mushroom but easy access as well as the lower cost of other agricultural and industrial lignocellulosic wastes have led to the introduction of a suitable alternatives. Due to the fact that the type of substrate used in the cultivation of Shiitake mushroom has a significant effect on the amount of protein and other chemical and medicinal properties of the fruit bodies, so in this study, we tried to investigate the physical and chemical changes of the substrate during the cultivation period of this fungus. To investigate the relationship between vegetative, reproductive growth, nutritional and medicinal value of Shiitake mushroom with different substrates and to introduce the best substrate for cultivation of this fungus.

This research was conducted in Zabol University from 2019-20. This study was conducted as a two-way factorial based on a completely randomized design with three replicates. Physical and chemical properties of the substrate were measured in two stages before spawn inoculation and after harvest of the fungus (consumed compost). Also, traits related to fruit bodies were evaluated as an average of two folds.

The nutritional value of the substrate is increased by adding organic supplements such as wheat bran, cottonseed meal and soybean meal to the substrates of poplar wood chips and sugarcane bagasse enriched with chemical additives such as potassium nitrate and magnesium sulfate. Therefore, fungal myceliums transfer more nutrients to the fruit body and increase the amount of Ergosterol (479.6), antioxidant capacity (40.1%) and total polysaccharide (10.95) of the fruit bodeis produced on these substrates than other substrates. Substrates containing poplar wood chips, wheat bran and cottonseed meal enriched with chemical additives had the highest yield (294.8). High levels of potassium (398.6) in the fruiting body of the mushrooms were obtained from substrates containing sugarcane bagasse, Date palm sawdust and vine sawdust. Also, high amounts of fruit bodies calcium (14.3) were observed in fungi harvested from substrates containing poplar wood chips, wheat bran and sugarcane bagasse. By measuring the percentage of decomposition changes in different agro-wastes used in this study in the pre-spawn Run stage and after the production of Shiitake fruiting bodies, it was determined that the amounts of Nitrogen, protein, ash and EC of the substrate increased and in contrast the values of pH, carbon and carbon to nitrogen ratio, cellulose, hemicellulose and lignin of the substrate decreased during the cultivation period of shiitake mushroom.

Agro-wastes and wood chips of forest trees have high amounts of lignin and high carbon to nitrogen ratio, and also the lack of complete degradability of these compounds, makes the fungal mycelium not able to fully absorb nutrients in the substrate. Therefore, in order to modulate the carbon to nitrogen ratio and also increase the activity of cellulose, hemicellulose and lignin degrading enzymes and increase the bioconversion efficiency (substrate to basidiocarp conversion), use of mixed substrates and organic and inorganic supplements in culture and production of Shiitake mushroom is recommended.

According to current reports, the main cause of global warming and climate change is the impact of greenhouse gases, especially carbon dioxide. Carbon sequestration in soil and plant biomass is the simplest and most economically viable solution to reduce the concentration of Co2 and atmospheric carbon. Due to interactions between the rate of carbon sequestration with crop management and soil characteristics especially salinity, the study of different management options can play an effective role in increasing carbon sequestration in lands with limitation. The purpose of this research was to evaluate the carbon sequestration of barley crop in the lands of Gomishan county (Golestan province) in two different sites with high EC (>12 dS/m) and low EC (< 12 dS/m).

To conduct this study, in first survey of field performed to determine the two mentioned areas in the fall of 2018. Then, 50 fields were selected as sampling sites that included as 25 samples from barley fields with high EC and 25 samples with low EC. Soil sampling was done before planting and after harvesting in barley fields. The amount of organic carbon accumulation in the soil resulting from the difference between these two sampling steps was considered as carbon sequestration. The combustion method was used to determine the amount of organic carbon in plant organs. Then, data of soil and plant carbon sequestration were entered into ArcMap software and these data were interpolated to the area according to different geostatistical methods and presented as thematic maps.

The results showed that the carbon sequestration potential by barley crop in the agricultural lands of southern of Gomishan county had the highest potential by 2369 kg/ha. Also, the amount of organic carbon in the above ground organs was estimated higher than the below ground organs due to its higher dry weight. The study of soil carbon sequestration in fields with EC >12 dS/m showed that barley crop played an effective role in regulating the decreasing trend of carbon sequestration in saline soils, which indicates the importance of barley crop in reducing soil salinity and resulted the carbon sequestration process changes.

In this study, results showed that carbon sequestration was negative in some barley fields. This result indicated that carbon emission is higher than carbon storage in soil during growing season. Therefore, the appropriate field management can affect on land quality improving, saline reducing and carbon sequestration increasing.

Increasing world population, along with climate change and environmental stresses, has posed a serious challenge to adequate food supply. Salinity is one of the most important stresses affecting the reduction of agricultural products. In recent years, the use of new strategies for sustainable production of food products under salinity stress has been considered, including plant growth promoting rhizosphere bacteria. Due to the strategic importance of wheat in food security, this study was designed and conducted with the aim of increasing the salinity resistance of wheat (Var. Narin) using plant growth promoting rhizosphere bacteria isolated from the rhizosphere of several halophyte plants in Yazd province.

Plant growth promoting traits such as ability to produce auxin, siderophore, hydrogen cyanide, and phosphate solubility and salinity resistance of isolated bacteria from rhizosphere of halophyte plants (Atriplex lentiformis, Seidlitzea rosmarinus, Halostachys belangeriana and tamarix ramossima) in their habitats in Chahafzal in Yazd Province were investigated. Then, wheat seeds were inoculated with the best three bacteria in terms of plant growth-promoting traits and salinity resistance, and then was irrigated with water with salinities of 4, 8 and 16 ds/m. After the growth period, the ion content of sodium, potassium, calcium and phosphorus in the leaves as well as some vegetative growth indices including stem length, stem and root dry weight and total biomass were measured.

The studied bacteria including Bacillus safensis, B. pumilus and Zhihengliuella halotolerans had the ability to produce auxin, siderophore, hydrogen cyanide, 1-aminocyclopropane-1-carboxylic acid deaminase (ACC deaminase) and phosphate solubility. The highest amount of auxin production was measured in B. safensis (29.72 μg/ml) and the highest amount of hydrogen cyanide production and phosphate solubility was in Z. halotolerans. The highest amount of ACC deaminase was measured in B. pumilus (8 μmol of α-ketobutyrate h–1 mg–1 protein). The results of wheat leaf analysis showed that at salinity stress levels, sodium content increased and other measured items decreased compared to the control. The use of bacteria reduced the sodium content by 142 percentage and increased the content of potassium, calcium and phosphorus in wheat leaf under salinity stress by 70, 92 and 295 percentage, respectively, compared to the control. Also, stem length, stem dry weight, root dry weight and total biomass in treatments under salinity stress and inoculated with bacterial isolates increased to 44, 56, 117 and 61 percentage, respectively, compared to the control

Plant growth promoting rhizosphere bacteria in this experiment significantly improved the resistance of wheat to salinity stress. B. safensis, more than the other two bacterial isolates, improved the growth indices of wheat var. Narin under salinity stress. These results also show that the rhizosphere of halophytic rangeland plants can be a good source for the isolation of salinity-resistant bacteria to improve the resistance of wheat plants to salinity.

Intercropping is an valuable cultivation system in all of the world due to the better use of resources and increase the quantitative and qualitative yield of plants. It also can be considered as one of the approaches to improve yield and stability in production. Recently, medicinal plants intercropped by legumes has been noticed. In order to evaluate faba bean and fennel intercropping advantage under row-replacement and additive series, an experiment was conducted in 2019.

This experiment was carried out at the research farm of the Azarbaijan Shahid Madani University, Tabriz, Iran, in a randomized complete block design with three replications. Treatments including 6:0, 4:2, 3:3, 2:4, and 0:6 of faba bean: fennel rows under replacement series and 6:3, 6:2, 2:6, and 3:6 of faba bean: fennel rows under additive series. After reaching a constant weight of fennel fruits, yiel and its components (number of umbels and umbellets and fruits per umbellet, 1000-seed weight, biological yield, seed yield, and harvest index) were measured in fennel plants. The essential oil content in fennel fruits was also measured using a Clevenger apparatus. Faba bean biomass was measured after harvesting plants in the flowering growth stage. Finally, the relative crowding coefficient, land equivalent ratio, actual yield loss or gain and intercropping advantage of faba bean: fennel mixed cultivation were calculated in the row-replacement and additive series.

The results showed that intercropping of faba bean and fennel had a significant effect on all studied traits. The highest number of umbels per plant was obtained from sole cropping (12.10). Also, the highest number of umbellets/umbel was related to intercropping of two rows of faba bean: four rows of fennel and three rows of faba bean: three rows of fennel by 22.05 and 19.62, respectively. The highest 1000-seed weight was obtained from sole cropping of fennel (5.62 g) and replacement intercroppings, especially from two rows of faba bean: four rows of fennel (5.56 g). The highest biological yield (1503.47 kg/ha) and seed yield (617.73 kg/ha) were obtained from the sole cropping of fennel. The maximum harvest index was related to the intercropping of three rows of faba bean: three rows of fennel, which shows that such a mixture ratio leads to the highest seed yield rather than biological yield produced. The highest fennel essential oil content was obtained from additive series. The highest faba bean biomass was found in the sole cropping (1933.02 kg/ha) and the lowest in treatments in which two rows of faba bean has been planted. Two rows of faba bean + six rows of fennel had the highest (3.96) relative crowding coefficient. The land equivalent ratio in all row-replacement and additive series was more than one or close to one, which indicates the usefulness of faba bean and fennel intercropping. The highest actual yield (0.07) and intercropping advantage indexes (0.17) were related to three rows of faba bean + three rows of fennel. Also, the lowest actual yield was related to additive series, especially treatments in which fennel had a higher mixture ratio than faba bean.

Based on the results obtained in this study, environmental resources including light, water, and nutrients have been used optimally in the three faba bean rows + three fennel rows and there was no effective competition to achieve them in this row-replacement series. In other words, ecological niche separation in this intercropping system has been done favorably, and subsequently the actual yield index increased. Therefore, the mixture ratio by 50:50 in the row-replacement series is recommended to achieve the highest benefit in semi-arid conditions where this experiment was conducted.

In recent years, the phenomenon of dusts caused by global warming and dehydration or drying of water resources, agricultural production as well as an environment has confronted a serious challenge. Dusts is one of the most important atmospheric phenomena and natural disasters, which is also considered as part of climate change and in recent years has gone out of its natural course and occurs in the western and southwestern regions of Iran. The destructive effects of dusts include reduced light reaching the plant, reduced yield of agricultural products, soil fertility reduction, disruption of mechanical systems and communications and the occurrence of respiratory problems.

In order to investigate the effects of dust on the physiological and morphological traits of crops, a pot experiment was conducted in the field research of the Faculty of Agriculture, University of Kurdistan, located in Dehgolan. This factorial experiment was performed in a randomized complete block design with 3 replications. Experimental factors included dust at 2 levels (with and without dust) and crop at 3 levels (cucumber, tomato and bean). After crossing of each dust system through the province, the dust was collected using reported methods. Dust spraying was done on the surface of crops (beans, tomatoes and cucumbers) in the middle of the growing period and early flowering stage. Then, 10 days after application of dust, physiological traits including chlorophyll content, protein concentration, proline content and soluble carbohydrates of leaves as well as morphological traits including leaf and stem weight and plant height were measured.

The results of this study showed that the effect of dust on the content of total chlorophyll and chlorophyll a, proline, protein and water-soluble carbohydrate was significant, while the dust had no significant effect on the content of chlorophyll b and soluble carbohydrate in alcohol. The results also showed that dust had a significant effect on leaf and stem weight and height of cucumber, tomato and bean. Also, different plants had significant differences in leaf weight and height. According to the obtained results, in general, tomato plant had more affected by dust than beans and cucumber and most of the measured traits were reduced, which is probably due to having more hairs on the leaf surface. In fact, dust by reducing the content of chlorophyll, soluble protein and soluble carbohydrate in the leaves and increasing the content of proline leads to a significant reduction in leaf and stem dry weight in cucumbers, tomatoes and beans, as well as a significant reduction in height in cucumbers and beans. It has been suggested that these damages may be due to reduced photosynthesis in crops. Cluster analysis of different traits and treatments also showed that the physiological traits of soluble carbohydrates in water were more correlated with each other and were in the same cluster with plant height.

The decline in crop yields in recent years, which is sometimes reported by farmers, may be due to the presence of dust and also the inhibition of the absorption of micronutrients through foliar application. Therefore, it is recommended that when dust systems pass through the area, if possible, sprinkler irrigation would be used to prevent dust damage.