نشریه تولیدات گیاهی
سال چهل و پنجم شماره 3 (پاییز 1401)

Introduction:

Iran, as the largest producer and exporter of pistachio (Pistacia vera L.), is among the major pistachio producing countries in the world including USA, Turkey, Italy and Greece. Due to the altered nature of the pistachio, the high yield of the pistachio is due to the fact that the environment is quite suitable and fertility of the female flowers is high. As the edible and consumable part of this fruit is its brain, it is essential for brain formation, pollination and intercourse. Therefore, it is more important for fruit formation, pollination and blending than many fruits. Therefore, the aim of this study was to investigate the effects of artificial parent pollination of integerrima species on seed properties obtained by crossing with Ahmad aghaei and also to compare the effects of integerrima pollen with domestic pistachio pollen on the quantity and quality of pistachio fruit and seed. 

Materials and Methods:

The experiment was conducted as factorial based on a completely block design with three replications in one of  the Astan Qods Razavi pistachio orchards in Bardsaskan-Anabed city, 297 km from Mashhad during 2016-2017. Experimental treatments included two pollinator methods (spray and brush) and five flour-pollen combinations (Table 1). Each replicate had one tree and five branches were selected from each tree with at least three to four flower buds. Four of them were controlled for pollination and one branch was considered for negative control. The branches were insulated by two-layer bags. The fruits were harvested in late summer and some quantitative and qualitative traits were measured. 

Results and Discussion:

The results of statistical analysis showed that the use of vera free pollen had a significant positive effect on most of the traits compared to other integerrima pollen treatments. On the other hand, integerrima pollen showed better results in IF4 treatment (0.50 g of integerrima pollen + 0.25 g flour) than control and other treatments. Also, the highest reduction of traits was observed in IF1 treatment (2 g of integerrima pollen + 0.25 g of flour) compared to other treatments in most of the traits. On the other hand, spraying method showed more favorable effects on most of the traits than brush pollinator method. Based on the results of this study, it seems that using spray pollinator and pollen of integerrima can reduce some traits such as Indehiscent nut in pistachio orchards. 

Conclusion:

In general, the results showed that supplemental pollination using spray-spraying method in flour-pollen mixtures can be commercially available to increase fruit formation, and reduce osteoporosis to some extent. However, little research is needed on the role of different pollen grains on the quantitative and qualitative traits of the resulting fruits.

Introduction:

The genotype × environment interaction is one of the most important factors in limiting breeding programs. The compatibility of a given genotype determines its ability and genetic capacity to produce high production and yield stability in different environments. Therefore, it is necessary to study the genotype × environment interaction in order to introduce stable genotypes in different environments. The current research was carried out to determine the compatibility and stability of yield for 10 tobacco genotypes and estimate the most stable genotype for tobacco growing areas in Iran (i.e. Guilan, Mazandaran and Golestan provinces). 

Materials and Methods:

In this study, 10 male sterile flue cured tobacco genotypes, which they completely tested in terms of quality and taste, including 7 internal modified hybrids named RVH5, RVH6, RVH8, RVH27, RVH30, RVH48, RVH70 along with 3 imported genotype DVH2101, PVH19 and NC100 in 6 tobacco growing regions of Guilan, Mazandaran and Golestan in two years of experiment (2018-2019). In total, 12 environments were studied in a randomized complete block design with 3 replications. Combined analysis was performed by considering the environments as a random factor and genotypes as a fixed factor. Then the stability analysis of genotypes was done by 10 stability statistics and the first 3 components of AMMI (Additive Main effects and Multiplication Interaction) analysis including IPCA1, IPCA2 and IPCA3. Analysis of variance was done using SAS.9 software, AMMI analysis and related graphs were performed using IRRISTAT software. 

Results and Discussion:

The results of combined analysis of variance showed that the effect of location and year × location interaction, the effect of genotype and genotype × year × location interaction were significant at the 1% probability level for yield. Genotype × environment interaction analysis using the first three main components of the AMMI analysis justified 69.47% of the total variance. The lowest coefficient of variation was related to DVH2101 and RVH27 genotypes. RVH30, RVH27 and RVH8 genotypes were selected as the most stable genotypes. According to Rick equivalence and Shoklaʹs stability variance parameters. The least squares deviation from the regression line were related to RVH27, RVH30 and RVH8 genotypes. In terms of regression coefficient, RVH27, RVH30 and DVH2101 genotypes had a line slope close to 1. Based on the coefficient of determination and Jenkins and Perkins statistics, RVH27, RVH30 and RVH8 genotypes were in the same rank in terms of stability. RVH27 and RVH30 were the most stable genotypes with superiority index. RVH27, RVH30 and DVH2101 genotypes were selected as the most stable hybrids based on the AMMI first model due to their proximity to the plot center, low interaction and high yield. Based on the second model of AMMI analysis, RVH27 and DVH2101 genotypes were selected as stable genotypes. In the third AMMI model, the RVH27 genotype was selected as the stable genotype due to its closeness to the biplot center and high yield. 

Conclusion:

Considering most of the stability statistics and AMMI analysis, the most stable genotype was RVH27 hybrid. RVH30 and DVH2101 hybrids were placed in the next categories of stability. In addition, genotypes RVH6 and NC100 showed high private compatibility to Tirtash tobacco growing area and genotype RVH27 to Rasht region.

Introduction:

Narcissus (Narcissus tazetta L.) belongs to the family of Amaryllidaceae is one of the most important ornamental and aromatic plants which its secondary metabolites are being used in cosmetic, sanitary and perfume industries. Behbahan district belongs to Khuzestan province is one of the well-known narcissus production centers in Iran. Narcissus plants not only have ornamental value, but also have medicinal compounds such as alkaloids that have antiviral and anti-tumor properties. Numerous experiments have been identified the components of Narcissus essential oil and the most significant of aroma constituents have been reported as trans-β-Ocimene, Benzyl acetate, 1, 8-cineole, linalool and phenyl ethyl acetate. However, there is little information about Narcissus extract and the current study was performed to investigate the compounds of ethanol and hexan extracts in different varieties of narcissus. 

Materials and Methods:

This research was conducted in randomized complete design to evaluate components of hexane and ethanol extracts of five narcissus varieties (Shahla, Meskinack, Porpar, Panjegorbai and Gol sefied) which are grown in Behbahan district. The fresh flowers of narcissus were extracted using tow solvents; hexane and ethanol. In the hexane extraction method, 10 g of the fresh flowers were weighed from each variety and poured into Erlenmeyer, and then 100 ml of hexane was added to each one and left at room temperature for 10 days. After extraction, the solvent was filtered and the extract was concentrated by vacuum rotary and absolute was obtained. Then 10 times of ethanol was added to the absolute of each variety and kept at -4 °C to precipitate the wax. After precipitation, the supernatant was separated and concentrated again by rotary and then the components were detected by GC/MS. In the ethanol extraction method, also 10 g of the fresh flowers were also weighed from each variety and poured into Erlenmeyer, and then 100 ml of ethanol was added to each one and left at room temperature for 10 days. After extraction, the solvent was filtered and the extract was concentrated by vacuum rotary and absolute was obtained. The rest of the steps are similar to the hexane method which is described above. 

Results and Discussion:

According to the results, the maximum amount of hexane extract (1.3%) and the minimum amount (0.9%) were observed in variety of Shahla and in Porpar, respectively. According to the results obtained from the analysis of the extract by GC/MS, approximately 7 to 12 compounds have been identified in narcissus varieties. Benzyl acetate, Linalool, Benzyl alcohol, trans -β-Ocimene, Hydrocinnamyl alcohol, Phenyl ethyl alcohol, 1, 3 Dimethyl ethyl benzene were the most important components. In ethanol extract, the maximum amount of ethanol extract (6.2%) and the minimum amount (4.8%) were recorded in variety of Shahla and in Porpar, respectively. Interestingly, more compounds were identified in ethanol than hexane extract. The most important compounds were 2-butoxy ethanol, 1, 8-Cineol, Benzyl alcohol, trans-β-Ocimene, Linalool, Phenyl ethyl alcohol, Benzyl acetate, Benzene ethanol and Benzene which were recorded in all varieties of narcissus. 

Conclusion:

In general, the results showed that there is a significant difference in terms of yield, number and percentage of chemical compounds of hexane and ethanol extracts of different varieties of narcissus. According to the results, the maximum amount of hexane and ethanol extract was obtained in Shahla while the minimum amount was observed in Porpar. Benzyl acetate, Linalool, Benzyl alcohol, trans-β-Ocimene, Phenyl ethyl alcohol, 1, 3 Dimethyl ethyl benzene are the most important components of both extracts. In order to isolate extract components and report exclusive compounds, further experiments are recommended. Keywords: Benzyl acetate, Extract, Gas chromatography, Linalool, Narcissus, Organic Solvents

Introduction:

Genetic diversity is one of the major goals of plant breeding. Mutation induction is a method to increase genetic variety that is used in plant breeding along with selection, recombination or a combination of the both. Rosa persica Michx can serve as a valuable genetic resource for breeding programs, especially due to the market demand for variety in rose cultivars as well as its drought resistance.  In two independent experiments, this study examined the effect of ethyl methane sulfonate (EMS) as a chemical mutagen on seed germination and seedling characteristics of Rosa persica. 

Materials and Methods:

 The seeds of Rosa persica Mich.seeds were collected from an adult shrub on the Arak University campus, Karbala St., Sardasht (34° N, 49.6° E) and an altitude of 1872 m above sea level during mid-summer. The seeds were separated from the hips by a sharp scalpel and the damaged and abnormal seeds were removed. Before applying the cold stratification, the seeds were washed for several hours and then placed in layers of wet sand at 4 ° C for 60 days.First, the effects of 0, 0.2, and 0.3% EMS at 4, 8 and 12 hours on seed germination characteristics were examined. Second, 0, 0.2, and 0.3 concentrations of EMS at 4 and 8 hours were studied on reproductive buds. Seed germination characteristics such as final germination percentage, germination rate index, coefficient velocity germination, germination rate, mean daily germination, daily germination speed, mean germination rate, germination index, seed vigor, seed dormancy and seedling vegetative traits such as stem lengths, root lengths, and leaf number are evaluated at first experiment. In second experiment, flower diameter, flower opening rate, number of necrotic buds and the number of seeds in each hip were measured. 

Results and Discussion:

The results showed that increasing the concentration of EMS and the time of seed treatment caused a further decrease in germination indices. In 0.3% EMS treatment for 8 hours on seeds, traits such as germination percentage, germination rate index and daily germination were reduced to zero. According to the results of the second experiment, leaf and seedling lengths were longer at 0.2 and 0.3% EMS concentrations and at 4 h incubation. There was a decline in the number of seeds per hip and an increase in necrotic buds with increasing concentration and time of EMS application. In order to succeed in a breeding program using mutagenic methods, the appropriate concentration and time must first be optimized. To determine the best concentration of mutagens, there are two important factors to consider: first, that the concentration should not be so high as to destroy plants, and second, that the applied concentration should be selected moderately. Although, that the frequency of mutations occurs sufficiently. 

Conclusion:

In order to induce a positive mutation and diversity in Iranian roses for the purpose of introducing a new cultivar, seed treatment with a concentration of 0.3% EMS and an incubation time of 4 h is recommended. It is also recommended to apply a concentration of 0.2% EMS on the reproductive buds for 4 h to induce mutations. Keywords: Seed, breeding, germination, mutation, ornamental plant

Introduction:

From an agricultural point of view, seeds are the starting point of all activities that lead to crop production. Today, agricultural machinery is one of the most important sources of environmental pollutants in mechanized farms and pollution caused by them can disrupt the germination process and plant growth. Therefore, in addition to a variety of environmental challenges, such as salinity and drought stress, contamination from agricultural machinery can also be added to germination and seedling growth as a threat. 

Materials and Methods:

Based on the gray correlation coefficient between the comparison series and the standard series, a relative series can be created. If γ (x_0, x_i) ≥γ (x_0, x_j), which indicates the degree of correlation between x_i and x_0, is greater than x_j and x_0; In this case, the relationship between potential causes and the optimal amounts of decision factors is shown. In the sense that a larger degree of connection has a smaller effect. Therefore, increasing the degree of prioritization of risk indicates the potential reasons that need to be improved. To analyze the risk of gaseous pollutants leaving the tractor exhaust, the treatment with the lowest gray correlation coefficient should show the highest risk priority. So that the highest degree of gray connection determines the best state of seed treatment. The aim of this study was to investigate the effect of pollutants from tractor exhaust in three different initial life, useful life and burn on canola seed germination. This factorial experiment was performed based on a completely randomized design with three replications. Experimental treatments include three different tractor life periods including initial life, useful life and wear as the first factor, and treatment for the duration of seeds exposed to tractor exhaust pollution including zero, 30, 60, 90, and 120 minutes as the factor. The second was considered. 

Results and Discussion:

The results showed that the highest values of root and stem length, germination rate coefficient, germination index, germination rate index and canola seed vigor were obtained from the absence of exhaust pollution; while the lowest amount of these traits was related to the treatment of exposure to contamination for 120 minutes and worn tractor. Conversely, the amount of seed protein and the activity of antioxidant enzymes catalase and peroxidase increased with increasing tractor wear and duration of contamination. Calculations based on gray theory showed that the treatment with a lower rank is the preferred treatment and has a lower risk according to all growth indices considered for rapeseed. In this study, zero time for different tractor lives without treatment, the risk was identified. Therefore, it is likely that increasing the exposure time to the tractor exhaust contaminant will gradually reduce the seed tolerance and poisoning threshold. 

Conclusion:

Gray's theory has shown that the duration of exposure is more important than the amount of contamination. The severity of exposure also varied depending on the degree of infection. Rapeseed seeds were more sensitive to contaminants from worn-out tractors than new tractors. The sensitivity of these seeds doubles the need to replace worn-out machines, service and repair tractors in a timely manner, use clean fuel, and use new or serviceable tractors.

Introduction:

Stevia rebaudiana Bertoni is a herbaceous plant from the family Asteraceae and used as a valuable sweetener in food industry and as anti-inflammatory, antioxidant, antipyretic, anti-fungal, and antibacterial agent in medicine and pharmacology. Piriformospora indica is an endophytic fungus, which is mainly used to improve plant growth and the amount of secondary metabolites. Selenium (Se) as an micronutrient increases the antioxidant properties and plant growth and its nano form (SeNPs) is considered as a synthetic antioxidant. To evaluate the effect of Piriformospora indica inoculation and selenium nanoparticles foliar application at two concentrations of 5 and 10 mg/l on biological activities of the methanolic extract of the regenerated S. rebaudiana plants, an experiment was conducted in 2020 in Plant Physiology Research Laboratory of the Bu-Ali Sina University of Hamadan in a factorial arrangement based on completely randomized design with three replications. 

Materials and Methods:

To investigate the effects of endophytic fungus P. indica and SeNPs application, in vitro regenerated Stevia plantlets were inoculated with P. indica and foliar sprayed with SeNPs at two concentrations of 5 and 10 mg/l. Plant samples were harvested at vegetative and initial flowering stages and used for further analyses. After measuring the growth parameters, total phenol content and antioxidant activity were evaluated by Folin-Ciocalteu and DPPH radical scavenging assays, respectively. In addition, antibacterial activity of the plant methanolic extracts was studied by disc diffusion method. 

Results and Discussion:

Inoculation of P. indica and application of SeNPs together resulted in plant growth improvement and also increase in total phenol content and antioxidant activity of the Stevia plants especially at vegetative stage. In addition, the studied extracts represented good antibacterial activity against two gram-positive bacteria, Bacillus thuringiensis and Staphylococcus aureus, and one gram-negative bacterium, Escherichia coli. The highest antioxidant and antibacterial activities were observed in the Stevia plants inoculated with P. indica and also treated with SeNPs. 

Conclusion:

Regarded to the results of the present study, P. indica inoculation and SeNPs application could result to the benefits in Stevia plants. Hence, it can be concluded that the biotic and non-biotic elicitors of P. indica and SeNPs can improve the antioxidant and antimicrobial activities of the Stevia plants by increasing the amount of total phenolic compounds.

Introduction:

Agriculture practices involve the extensive utilization of chemical fertilizers that lead to several impacts, namely groundwater pollution, eutrophication, and production of greenhouse gases. These ultimately lead to environmental pollution and pose several health risks. With this respect, plant growth promoting rhizobacteria (PGPR) consist of a diverse collection of rhizobacteria that occur in the rhizospheric zone and interact with plant roots. Moreover plant growth promoting rhizobacteria (PGPR) are a heterogeneous group of bacteria found in the rhizosphere, associated with roots and root surfaces or living freely in the soil and influencing plant growth directly or indirectly. A large number of bacteria is reported to contribute to plant growth, including species of Pseudomonas, Azospirillum, Azotobacter, Klebsiella, Enterobacter, Acinetobacter, Alcaligenes, Arthrobacter, Burkholderia, Bacillus, and Serratia. Additionally, several reports indicate the application of ACC-deaminase-producing PGPR in facilitating plant growth and inducing tolerance in various abiotic stresses, namely (1) salt stress, (2) drought stress, (3) heat stress, (4) chilling stress, etc. The present study was performed to screen PGPR strains with different PGP traits in calcareous soils under salinity condition and to use such PGPR strains as biological inoculation.  

Materials and Methods:

In this study, 45 rhizospheric soil samples were collected from different crops in agricultural farms and placed in plastic bags, and transported to a laboratory, where it was refrigerated at 4 ° C until further use. To obtain a solution of 10-4 to 10-6 dilutions, one milliliter of suspension was serially diluted and 100 microliters of this suspension solution were spread onto the sterile nutrient agar medium. plates were incubated at 28±2°C for 48 hours in a BOD incubator. Rhizobacterial isolates with a different morphological appearance and fast growth on agar plates were randomly selected and purified by repetitive streaking on the fresh medium. After purification, these PGPR isolates were screened for PGP traits. Isolates with phosphate solubilization, siderophore production, IAA production and ACC-deaminase production were screened and finally three isolates were selected for molecular identification and pot experiments. 

Results and DiscussionIn:

 this research, a total of 45 rhizospheric soil samples were collected from the rhizosphere of different plants. 181 isolates were purified and isolated. In the initial screening, some of them were characterized by phosphate solubilization, siderophore production and indole acetic acid (IAA) production. In the secondary screening, superior isolates were selected in these three growth-promoting traits, and in the ACC-deaminase production test, all three isolates were able to produce this enzyme. Molecular identification of the isolates was performed by 16S rRNA gene sequencing technique and the isolates belonged to Bacillus Cereus, Pseudomonas Syringae and Pseudomonas Alcaliphila which were registered in the NCBI database. In greenhouse experiments, inoculation of Pseudomonas Alcaliphila showed the best performance shoot length, shoot dry weight, chlorophyll production, crude protein production of alfalfa (medicago sativa L.) and lowest proline production under salinity stress, while inoculation of Pseudomonas Syringae had better yield at root length and root dry weight. 

Conclusion:

Extremely cost-effective methods such as applications of microorganisms with PGPR activities can enhance plant growth, speed up seed germination, improve seedling emergence, and protect plants. In conclusion, the applied plant-growth-promoting rhizobacteria (PGPR) bacterial SF1050 strain (Pseudomonas Alcaliphila) proved to be a potential candidate for improving alfalfa crops in salinity conditions. Nevertheless, it is suggested to validate the current results by conducting field trials.

Introduction:

Reducing the genetic diversity of crops as a result of the use of breeding processes leads to the loss of a large number of useful genes and thus reduces the diversity of genetic resources, which is one of the undeniable tools of breeding programs. Therefore, researches aimed at studying the genetic diversity of crops can be an effective aid in preserving genetic resources and identifying superior genotypes. Electrophoresis of seed storage proteins is a useful tool to study the characteristics of wheat genotypes in terms of storage proteins diversity. 

Materials and Methods:

In the present study, the diversity of seed storage proteins of 25 durum wheat genotypes obtained from different regions of Iran, including some landraces and commercial cultivars, was investigated using SDS-PAGE electrophoresis. Storage proteins of the studied genotypes were scored and analyzed after extraction and electrophoresis. Grain protein content and total gluten were measured by NIR and glutomatic gluten washer machines, respectively.  

Results and Discussion:

Electrophoresis identified 14 polymorphic bands. Molecular analysis of variance between landraces and commercial cultivars showed 100% intragroup diversity. Cluster analysis using Jaccard coefficients by UPGMA method divided the studied genotypes into 4 groups. Genotypes No. 9 (Land race of Mashhad), 18 (Land race of Ahar) and 24 (Landrace of Islamabad Gharb) were placed each in a separate group and the rest of the genotypes formed another group. The two-dimensional graph resulting from principal component analysis also confirmed these four groups. Based on Jaccard similarity matrix, the lowest similarity and highest genetic distance were determined between genotypes No. 24 (Land race of Islamabad Gharb) with genotypes No. 21 (Dehdasht cultivar), 22 (Land race of Khorramabad), 23 (Dena cultivar) and 25 (Land race of Khorramabad) with a similarity coefficient of 0.41 was obtained. On the other hand, comparing the mean of genotypes for qualitative traits of grain protein content and total gluten, the highest amount of these two traits for genotypes No. 3 (Landrace of Kermanshah), 4 (Landrace of unknown-Iran), 1 (Landrace of Khoram Abad) and 2 (Landrace of Khoramabad) and the lowest values of both traits were obtained for genotype No. 24 (Landrace of Islamabad-West). Genotype No. 18 (Landrace of Ahar) is also one of the genotypes with high amounts of gluten. 

Conclusion:

The electrophoretic pattern of seed storage proteins can determine genetic diversity based on the presence or absence of protein bands. Therefore it can be a useful tool to identify the genetic diversity of different plants. It is also possible for genotypes that have the greatest genetic distance and at the same time have good quantitative and qualitative traits to participate in breeding programs as parents. In the present study, according to the study of genotypes by analyzing the variance of qualitative traits of grain protein content and total gluten and comparing the mean and grouping them using the information obtained by electrophoresis, a cross can be found between genotypes genotypes No. 3 (Landrace of Kermanshah), 4 (Landrace of unknown-Iran), 1 (Landrace of Khoram Abad) and 2 (Landrace of Khoramabad) Due to their high content of gluten and protein with genotype No. 18 (Landrace of Ahar) due to its high content of gluten and acceptable genetic distance with the mentioned genotypes

Introduction:

Wheat (Triticum aestivum L.) is one of the most important and strategic crops worldwide. Drought stress is one of the important and abiotic stresses that reduces the growth and yield of plants.in arid and semi-arid regions. Today, the economic damage and destructive effects of the environment due to the excessive use of chemical fertilizers in agriculture are known worldwide, and it is obvious that a suitable alternative must be found for these fertilizers. Currently, biofertilizers are used as an alternative to chemical fertilizers based on the principles of sustainable agriculture and stress tolerance of plants. Salicylic acid is a natural phenolic compound that is involved in reducing the harmful effects of abiotic environmental stresses and regulating vital physiological processes in plants. 

Materials and Methods:

This study was carried out to assess the effect of fertilizer nutrition and foliar application of salicylic acid on wheat tolerance of Chamran 2 cultivar to drought stress experiment as a factorial split plot in the form of a randomized complete block design in the 2019-2020 crop year in the research farm of the Faculty of Agriculture of Lorestan University in three replications was performed The experimental site was located at a latitude 33°26′ N, a longitude 45°17′ E, and an altitude of 1210 m with a semi-arid climate, mean annual precipitation of 462.8 mm, mean annual evaporation of 1842.52 mm, and mean annual temperature of 16.6 °C .Main plot includes irrigation levels in two levels of without stress (100% of field capacity) and drought stress (50% of field capacity) and sub-plots including fertilizer in five levels including no use of biofertilizer + 50% chemical fertilizer, application of 100% chemical fertilizer, seed inoculation of nitroxin biofertilizer + 50% chemical fertilizer, seed inoculation of mycorrhizal + 50% chemical fertilizer, (simultaneous use of biofertilizers (nitroxin + mycorrhiza) + 50% chemical fertilizer, and foliar application treatment at two levels (foliar application with water and foliar application with a concentration of 1 mM salicylic acid). 

Results and Discussion:

The results showed that drought stress increased grain protein and malondialdehyde and decreased other evaluated traits. Fertilizer nutrition and salicylic acid foliar application treatment alone increased the evaluated traits and decreased malondialdehyde content compared to the no use of biofertilizer + 50% chemical fertilizer and no foliar application of salicylic acid. Combined treatment of fertilizer (nitroxin + mycorrhiza) + 50% chemical fertilizer and salicylic acid could reduce the effect of drought stress on the traits evaluated in this study on wheat of Chamran 2 cultivar. As a result can this treatment suggested to the farmer in order to reduce the consumption of chemical fertilizers in the cultivation of this wheat variety under drought stress conditions. 

Conclusion:

In general, it can be concluded that the application of biofertilizers (nitroxin + mycorrhiza) + 50% chemical fertilizer and salicylic acid foliar application can be used as an effective and alternative fertilizer to reduce the use of chemical fertilizers and water shortage in Khorramabad for sustainable agriculture. As a result, this treatment can be recommended to the farmer to reduce the use of chemical fertilizers in the cultivation of this wheat cultivar under drought stress conditions.

Soil salinity is one of the largest global challenges especially in the arid and semi-arid regions. It adversely and severely affected agricultural production and consequently food security. The new cereal, tritipyrum, is an artificial hexaploeid wheat (2n=6x=42, AABBEbEb) derived from crossing between Triticum durum (2n=4x=28, AABB) and Thinopyrum bessarabicum (2n=2x=14, EbEb) species that has good potential to be used as a seed or forage plant. The aim of present research was evaluating saline tolerance of new primary different tritipyrum lines through assessing some agronomical traits and ion distribution in plant under mild and severe salinity stress conditions.  

Materials and Methods:

A split-plot hydroponic experiment based on completely randomized block design with two factors and three replications was carried out at Shahrekord University in 2020. The NaCl salinity stress was considered as the main factor with 3 levels (0, 100, 200 Mm) and the genotypes were considered as sub plots with 8 levels. Genotypes included three primary tritipyrum lines (Ka/b, La/b, St/b), three combined tritipyrum lines (i.e. F4, F5 and F6 generations of a combined (Ka/b) (Cr/b) lines), as well as one durum wheat (cv. Creso) and a promising triticale line (Ma45). Different salinity stress levels were imposed from three leaf stage till maturity via irrigating the plants by appropriate saline water. The leaf surface area, fertile florets per spike, 1000-grain weight, grain yield, biological yield as well as concentration of Na+ and K+ and Ca++ ions in both root and aerial parts of genotypes were measured. 

Results and Discussion:

There were significant differences between genotypes in the case of all measured traits. Regardless of salinity levels, tritipyrum line (ka/b) (cr/b) (F6) had the highest amount of biological yield, grain yield, concentration of K+ and Ca++ and K+/Na+ ratio in shoot and the least amount of Na+ in shoot. With increase in salinity level from 0 to 200 mM, flag leaf area, number of fertile florets, 1000 grain weight, biological yield, grain yield and amount of K+ and Ca++ in both root and shoot were significantly reduced in almost all genotypes and concentration of Na+ was increased. At 200 mM salinity, all of the three combined tritipyrum lines had significantly higher amount of biological yield and K+ concentration in shoot and less amount of Na+ in shoot than durum wheat and triticale. Shoot Na+ concentration had negative significant correlation with flag leaf area and 1000 grain weight. In the other hand, positive correlation was observed between shoot K+ concentration and flag leaf area, number of fertile florets, 1000 grain weight and grain yield. At 200 mM salinity, the highest and lowest shoot K+/Na+ ratio were observed in tritipyrum line F5 and durum wheat, respectively. On average, root sodium concentration in tritipyrum lines was higher than that of wheat and triticale while shoot sodium concentration in tritipyrum lines was less than that of the two other genotypes. 

Conclusion:

Results of our experiment suggest that hindrance in the transfer of Na+ from root to the aerial parts is probably one of the mechanisms that used by tritipyrum lines to cope with the high NaCl concentrations.

Backgrounds and Objectives:

Direct seeding is being developed in many Asian countries as a new technology that farmers are tending to use this technology in current years considering that it has appropriate economic efficiency, faster and easier cultivation, less labor force, more mechanization and shorter growth period than transplanting cultivation and due to discontinuous irrigation, less methane emission. But what makes it mainly obstacle are weeds.The use of seed priming can be one of methods that it can compensate the paucities of direct seeding and get promote seed quality. Seed priming also can active the initial germination mechanisms before planting and many benefits were mentioned for this treatment that the most significant of them is increasing the percentage and rate of germination. Indeed these plants expand their root system in shorter period of time compared untreated seeds. They are also reached to autotroph stage earlier by absorbing more water, nutrients and producing photosynthetic part. 

Materials and Methods:

The field experiment was conducted in Neka in 2018. The experiment was performed as a factorial in randomized complete block design in three replications. Experimental treatments include  seed priming in four levels 1- no priming, 2- hydropriming (priming with water), 3- priming with humic substances (10 g per 1.5 liters of water) 4- priming with auxin hormone (1.5 cc in 1.5 liters of water) and also, weed management at five levels 1- no weeding, 2- council active herbicide (15 g per 20 liters of water), 3- twice weeding (one month after planting + before the earing stage), 4- council active herbicide (15 g per 20 liters of water applied about one month after planting) + weeding (1.5 months after planting) and 5- complete weeding (weeding of all weeds during the growing season). 

Results:

Based on the results, by applying seed priming with humic acid, the maximum plant height, ear length and number of plants m-2 were obtained and complete weeding caused the maximum plant height, fertile tiller, total tiller and ear length. Also, seed priming with humic acid along with complete weeding caused the highest filled grain number (79.67 number) and total grain number (90 number), 1000-grain weight (23.47 g), grain yield (2327 kg ha-1), biological yield (11220 kg ha-1). Based on total weed density and biomass, in all three stages of sampling, the lowest amount of weed biomass and density was obtained with application of humic acid priming along with council active herbicide + weeding, which was not significantly different from application of humic acid priming and twice weeding and application of auxin with council active herbicide + weeding and twice weeding. Overall, the findings of this study indicate the effect of priming of rice seeds especially with humic acid and auxin along with council active herbicide + weeding and twice weeding, on reducing the weeds density and biomass as well as increasing the yield and yield components of rice in direct cultivation. 

Discussion:

According to results which were obtained this research and evaluation of yield and yield components are identified that application of herbicide cannot control the weed solitary. This research was showed that application of council active herbicide + weeding and twice weeding cause to reduce the weeds density and biomass as well as increasing the yield and yield components of rice in direct cultivation and also own to elimination of competing species, they improve the crop growth. Therefore, mechanical weeding, which is a non-chemical method of weed management, should be considered as a necessary part of sustainable agriculture.

Introduction:

Improving crop yields can meet the projected demand in developed and developing countries as a key and promising solution. To increase dryland wheat production in arid and semi-arid regions such as Iran, researchers and crop breeders need to understand the drought pattern (in terms of time and intensity) occurring in wheat agro-systems because depending on the time and intensity of drought stress, drought stress impacts on different processes and genes of crops. To accurately study the drought pattern of dryland wheat and different cultivars adapted to these conditions, researchers need to design multi-environmental field experiments, which are time-consuming and costly. Under these circumstances, some essential information is limited in the field experiments, especially when done for only a few years, and basically does not indicate fluctuations in the target environments. In contrast, the modeling and simulation approach is a useful method for comprehensive environmental impact assessment. 

Materials and Methods:

This study was conducted to identify and study different drought patterns in 8 locations including Ardebil, Khalkhal, Maragheh, Marand, Meshginshahr, Sarab, Tabriz, and Urmia in the northwest of Iran. APSIM model was used to simulate the growth and development of dryland wheat in the study locations. The long-term climatic included minimum and maximum temperatures, rainfall, and radiation (1980 to 2016) collected from the Meteorological Organization of Iran. These data were used as input to the crop growth simulation model. Water supply and demand index was used to determine different drought patterns. This index is obtained by dividing soil water content to plant water demand (WSDR). After calculating the water supply and demand index for each year and region, the CLARA clustering method was used to classify and group the index. The number of groups obtained by CLARA method was equal to the type of drought patterns of dryland wheat. 

Results and Discussion:

The results showed 4 different drought patterns during the dryland wheat growing season in the study locations.  Drought pattern 1 showed no drought stress or mild drought stress throughout the growing season of dryland wheat. Under drought pattern 2, drought stress started before flowering and ended during seed filling. For drought pattern 3, water stress started from the time of germination but removed during the vegetative growth period. Drought pattern 4 started in the early stages of growth and continued until the end of the dryland wheat growing season. The frequency of occurrence of 1, 2, 3, and 4 drought patterns was 27.8%, 26%, 8% and 38.2%, respectively. On average across locations, transpiration was 160, 137.1, 31, and 86.7 mm for 1, 2, 3, and 4 drought patterns during the wheat growing season. Also, a significant difference was observed among different drought patterns in terms of biomass that biomass under drought patterns 1, 2, 3, and 4 was equal to 13411, 10076, 2097 and, 6435 kg ha-1, respectively. Grain yield under drought pattern types 1, 2, 3 and 4 were 3738.7, 2949.7, 694.6, and 1456.2 kg ha-1, respectively. The highest percentage of light and mild drought patterns (1 and 2) was related to Marand region with 100% and Sarab region experienced more severe drought patterns (3 and 4) than other regions (88.2%). Under different locations and drought patterns, on average across years, the highest grain yield was simulated for Marand under drought pattern 1 (4759 kg ha-1) and the lowest was recorded for Urmia under drought pattern 3 (208.8 kg ha-1). 

Conclusion:

In general, the simulation results showed that 4 different types of drought patterns were observed during the dryland wheat growing period in the study locations. The frequency of occurrence of 4 drought patterns was various in the study locations and the grain yield varied under the drought patterns. However, the highest occurrence was related to drought pattern 4, under which drought stress begun in the early stages of growth and lasted until the end of the dryland wheat growing season. Accordingly, it is suggested to consider various strategies such as using cultivars with short maturity period to avoid drought stress at the end of the season and using cultivars with high resistance to drought stress (especially in the flowering period).