مجله تولید گیاهان زراعی
سال چهاردهم شماره 2 (تابستان 1400)

Environmental stresses are always one of the most important factors in reducing the crops yield and production. When plants encountered with flooding stress, the concentration of active oxygen species increases. Increasing these compounds can damage to several cellular metabolic responses, such as Membrane integrity, photosynthesis and photosystem II efficacy. Following these events, early leaf aging and leaf area reduction may result in the loss of carbon fixation in the plant. Plants, in order to Confront with activated oxygen species, produce antioxidants, which reduces the effects of stress. Accordingly, this research was carried out to investigate the effects of flooding stress during tillering and stem elongation in two Koohdasht and Morvarid wheat cultivars on the content of antioxidant enzymes, photosynthetic pigments and their relationship with grain yield.

To conduct this research, a factorial experiment was conducted in a completely randomized design at Gorgan University of Agricultural Sciences and Natural Resources in two years, 1394 and 1395. The experimental treatments consisted of the length of the stress period at five levels (0, 7, 14, 21 and 28 days) as the first factor, the time of flooding based on the development stage of wheat (tillering and stem elongation) as the second factor and cultivar (Koohdasht and Morvarid) were considered as the third factor. In order to apply flood stress, the pots for each treatment were somehow placed in a water-filled pond that plants stem at a height of 2 cm was below the water. After applying stress treatments, traits such as content of catalase and superoxide dismutase enzymes, ascorbic acid, chlorophyll a, chlorophyll b, cartenoied and grain yield were measured. Also, linear models were used to describe the relationships between measured traits and flooding duration.

The results of this study showed that the damages of flooding stress in wheat depend on the time of plant placement under stress, the developing stage that stress associated with it, and the type of cultivar. In general, in this study, with increasing flooding duration, traits such as content of catalase and superoxide dismutase enzymes as well as ascorbic acid content increased significantly (linearly), but the amount of photosynthetic pigments (linearly) decreased significantly. On the other hand, the rate of increase of catalase and superoxide dismutase enzymes in Koohdasht was more than Morvarid. Also, the reduction of chlorophyll a and chlorophyll b in Morvarid was higher than in Koohdasht, but the reduction of cartenoied in Koohdasht was higher than in Morvarid cultivars. Finally, with increasing the duration of flooding period, the grain yield of Koohdasht and Morvarid cultivars decreased by 3.67 and 3.20 percent per day, respectively. In both cultivars, flood stress during stem elongation stage decreased seed yield significantly more than the tillering stage.

Flooding stress has a very important role in reducing wheat grain yield. In this regard, the duration of the stress period was the most important factor affecting the yield, and then the developmental stage where the stress occurred during it and the cultivar were ranked second and third, respectively. Increased content of catalase and superoxide dismutase enzymes was associated with reducing the grain yield, as the production of these enzymes occured in response to increased active oxygen species (oxidative stress) during the flooding. Reduce the content of photosynthetic pigments also means a reduction in plant photosynthetic capacity during flooding stress. The total of these changes led to a linear decrease in grain yield in both cultivars and both developmental stages. The more severe reduction in grain yield, when flooding occurred at the stem elongation stage, indicates the greater sensitivity of this developmental stage to stress.

Quinoa is a plant of Amaranthus family, a genus of Chenopodium. Having a wide variety of genetic variations and flexibility allows the plant to adapt to different environments. One of the factors that should be considered when planting a plant in the pattern of cultivation in each region is the planting date of the plant. This factor can affect grain yield and quality by affecting vegetative and reproductive growth period in Quinoa. Sowing date is one of the most effective factors in completing different stages of plant growth. Since observing proper sowing dates will result in higher economic performance without any additional expense and will allow the plant to show its full potential.

In order to study the effect of planting date on phenological, morphological, yield and yield components of Quinoa, a study was conducted on different planting dates on the Quinoa. This study was carried out at a greenhouse complex of Agricultural Jihad in Khalilabad, Khorasan Razavi province, during 2018in a randomized complete block design with three replications and 12 different sowing dates. The cultivation was carried out on March 5 and at intervals of 15 days.

The results showed that the sowing date was significant for the number day of planting to emergence, planting to four leaves, planting to emergence of inflorescence, planting to change the color of inflorescence and planting to harvesting. The results showed that the time from sowing to emergence was reduced by increasing the environment temperature. The results of the experiment showed that the effect of sowing date at 1% probability level was significant on number of seeds per plant, 1000 seed weight, and seed weight per plant, grain yield, biological yield and Harvest Index. The highest grain yield was obtained in sowing date on March 5(2387 kg.ha) and the lowest in sowing date on May 20th (75 kg.ha). The highest biological yield was related to the sowing date of March 5 (10964 kg.ha) and the lowest was related to the sowing date of August 21 (3739 kg.ha), which did not show any significant difference with the sowing date of August 6.

In general, the results showed that different sowing dates due to changes in temperature and day time could affect the morphological, phenological, yield and yield components of the Quinoa under the experimental conditions. The results showed that the flowering stage and seed filling in the Quinoa was one of the sensitive growth stages of the plant to temperature, because the increase in temperature, especially in the flowering and pollination stage, led to a sharp decrease in the number of seeds and, finally, a significant reduction in the grain yield of this plant. In sum, the best sowing date for the Quinoa was obtained based on the information obtained from this study for March 5 and March 21.

Optimization of fertilizer and plant density are management approaches to improve resources efficiency and decline environmental pollutions. Response surface methodology (RSM) is defined as a set of mathematical and statistical techniques that are used to develop, to improve or to optimize a product by using Central composite designs. In this work, optimization of cow manure and plant density on biomass yield and essential oil percentage of peppermint as a medicinal plant species using central composite design for RSM was evaluated.

An experiment was conducted using central composite design with 13 treatments and two replications at the Research Field of Ferdowsi University of Mashhad during the growing season of 2017-2018. The treatments were allocated based on low and high levels of plant density (10 and 15 plants.m-2, respectively) and cow manure (0 and 70 t.ha-1, respectively). Fresh weight of stem, dried weight of stem, fresh weight of leaves, fresh weight of leaves, total dried weight and essential oil percentage in two sampling times and two cuttings were measured as dependent variables and changes of these variables were evaluated by a regression model. Lack-of-fit test was used to evaluate the quality of the fitted model. The adequacy of the model was tested by analysis of variance. The full quadratic polynomial equation was tested to determine the significance of the model and the component of the model (linear, squared and first-order interaction terms) and the quality of the fitted model was judged using the determination coefficient (R2).

The results showed that effect of linear and square components were significant on all studied characteristics in two sampling times. Interaction between the two factors of manure and plant density was significant on the studied traits only for the second sampling stage. Lack of fit had no significant effect on the studied traits. The full square model for the response variables gave insignificant lack-of-fit indicating that the data were satisfactorily explained. In the first and the second cuttings, R2 ranges for biomass yield and biomass yield+ essential oil were 70.39-84.62% and 27.36-63.06%, respectively. The highest observed and predicted values of biomass yield were recorded in 12.5 plants.m-2+ 35 t.ha-1 cow manure (755.13 g.m-2) and 15 plants.m-2+ 35 t.ha-1 cow manure (319.92 g.m-2), respectively. The mean yield of biomass yield in the second cutting was higher than the first cutting. Optimum levels of plant density and cow manure and desirability for biomass yield were calculated with 10 plants.m-2+23 t.ha-1 and d= 0.94 and the parameters for biomass yield, and essential oil percentage were with 10 plants.m-2, 49 t.ha-1 and d= 0.96, respectively.

In general, it seems that resource use optimization using RSM may be suitable cropping approach for sustainable production of medicinal plants in agroecosystems.

Peanut is one of the most important oilseed plants with indeterminate growth habit, which its seed and meal contains a range of 40-50% and 30-50% oil and protein on a dry seed basis, respectively. In many countries, peanut is planted as ridge method which help to control weeds by mechanical methods using rotary or cultivator. Also, a suitable plant density per unit area can improve photosynthetic process and enhance quantitative and qualitative yield in peanut seed. In the present study, we evaluated the influence of planting method and plant density on seed yield and physiological characteristics in some new lines of peanut under Guilan climatic condition.

In order to determine the best planting method and plant density to improve seed yield of some new lines of peanut, two experiments carried out in 2017 - 2018 cropping seasons as split-split plot based on randomized complete block design with three replications in Rasht, Iran. Two planting methods (Flat and Ridge), three plant density per hectare (D1=125000, D2= 100000 and D3= 83333) and five new lines of peanut (128, 176, 192, 201 and 208) comprised experimental treatments as main, sub and sub-sub plots, respectively.

Results showed that 192 new line produced the greatest seed yield per hectare (3128 kg/ha), seed number per pod (2.08) and biological yield (8983 kg/ha) in response to flat method and D1 plant density. Also, the interaction effect between flat planting method, 100000 plant per hectare and 176 line showed the highest seed oil content (57.67 %). The highest harvest index (40.29%) was observed in 128 new line under flat planting method and 100000 plant per hectare.

In general, results showed that the flat planting method, 125000 plant per hectare and 192 new line of peanut caused to enhance seed yield of peanut under Guilan climatic condition. In this experiment, flat planting method had superiority to ridge planting method and new lines of peanut were differ for seed yield per unit area. The results of this experiment, indicated that peanut seed yield enhanced due to increase of plant density per unit area which could be caused by improvement of solar radiance absorption, exceed of photosynthetic capacity, optimized uses of field unit area and decline of inter plant competition. Based on results of this experiment, flat planting method, 125000 plant per hectare and 192 new line of peanut could be recommendable in direction to enhance seed yield of peanut under Guilan climatic condition

Lavender is widely cultivated worldwide with its economic and ornamental potential and its high use in the cosmetic and pharmaceutical industries. Drought is one of the most important factors limiting plant growth worldwide and the most common environmental stress. In general, drought is considered to be the major environmental factor causing disturbance in water status and having a key impact on physiological and biochemical processes such as increased plant osmolality. In response to environmental stresses, abscisic acid plays an important role in initiating and coordinating many physiological and biochemical processes in reducing oxidative stress. Due to the fact that drought and water deficit in Iran is always one of the most important agricultural problems and due to the unique medicinal properties of lavender, the present study was conducted to evaluate the yield, physiological and biochemical properties of Lavandula angustifolia cv. Organic Munstead in irrigation regimes and application of abscisic acid was performed in order to understand how to induce drought tolerance.

In order to study the effects of drought and abscisic acid on physiological and biochemical characteristics of Lavandula angustifolia cv. Organic Munstead, a pot experiment was conducted as factorial based on randomized complete block design with three replications at Plant Production faculty of Gorgan University of Agricultural Sciences and Natural Resources, during growing season of 2017-18. The first factor was irrigation regimes in four levels (30-40, 50-60, 70-80 and 90-100% field capacity) and the second factor was abscisic acid spry including three levels (0, 15 and 30 µM/L). Traits evaluated were wet and dry weight and leaf area index, total phenol, total flavonoid, DPPH antioxidant activity, proline, carotenoid, RWC and soluble carbohydrate.

The results showed that drought increase phenol (151.42 mg/g) and carotenoid (46.32 mg/g) compared to control. Abscisic acid had significant effect on all traits except of phenol and carotenoid. Also interaction effect of drought and abscisic acid was significant for all traits except of phenol and carotenoid content that were the highest in abscisic acid 30 µM/L and drought 30-40 and 50-60 percent field capacity increase antioxidant activity 47.56 and 53.93 percent and 55.20 and 65.72 percent soluble carbohydrate, respectively. abscisic acid 30 µM/L spray and drought 30-40 increase proline 120.17 percent. Also, the highest RWC amount (78.74 percent) from interaction abscisic acid 30 µM/L and drought 90-100 percent field capacity.

Generally, abscisic acid 30 µM/L application and drought 30-40 and 50-60% field capacity Introduces the best treatment, due to the lower consumption of water and the use of abscisic acid in stress conditions, higher levels of abscisic acid can be achieved in inducing drought tolerance.

Grain filling period and grain filling rate are among the traits that affect plant response to heat stress. Our knowledge about the the status of these traits in Iranian commercial bread wheat cultivars under normal and heat stress conditions is so rare if not available. The purpose of this study was to evaluate grain filling duration and grain filling rate of Iranian commercial bread wheat cultivars and to study genetic diversity under normal and heat stress of the earth's hottest places, Ahvaz condition.

The experiments were conducted during 2017 and 2018 under normal (optimal planting date) and terminal heat stress (delayed cultivation) conditions on 33 commercial bread wheat cultivars including: Kaz (international heat tolerant), Montana (international heat sensitive), two other international cultivars, weebill and babax and 29 commercial varieties in Iran, namely Roshan, Arvand, Ghods, Flat, Hirmand, Alvand, Verinac, Zagros, Kavir, Chamran, Marvdasht, Shiraz, Dez, Pishtaz, Hamoon, Bam, Sistan, Neyshabur, Sepahan, Arta, Bahar, Arg, Pars, Aflak, Chamran 2, Mehregan, Shosh, Barat and Khalil. The experiment was conducted as a randomized complete block design with three replications at the experimental field of Shahid Chamran University of Ahvaz.

The results of combined analysis showed significant differences (P≤0.01) between genotypes, environment (heat stress) and also genotype-environment interaction for grain yield, grain filling duration and grain filling rate. In general, grain yield and grain filling period of cultivars were significantly reduced under stress condition compared to non-stress condition. However, grain filling rate decreased in most cultivars and almost increased in tolerant cultivars such as kaz. Results of principal component analysis showed that Hamoon, Kaz, Chamran 2, Arvand, Chamran, Falat, Verinac, Alvand, Mehregan and Shosh had high yield and yield stability under heat stress condition. The coefficient of genotypic and phenotypic variation for different traits indicated significant variation for all traits. In addition, significant heritability and genetic improvement were estimated for grain filling rate. This trait showed a high correlation with grain yield under both stress and non-stress conditions.

Among the commercial bread wheat varieties Chamran 2, Shoush and Alvand showed considerable heat tolerance compared to the international heat tolerant cultivar, Kaz. Grain filling rate was identified as an important trait in optimal response of plants to terminal heat stress. The results showed good genetic variation among commercial bread wheat varieties for grain filling rate. This trait can be used to identify and enhance heat tolerant varieties in breeding programs.

Legumes are considered as one of the most important plant sources that rich in protein and after cereals are the second source of human food. Among legumes, beans (Phaseolus vulgaris L.) due to economic value and area under cultivation are first in rank of the world. Nitrogen is one of the most important nutrients needed by plants and plays an important role in increasing yield, but environmental issues, especially increasing the concentration of nitrate in shallow groundwater in northern Iran have led to the use of biofertilizers. The purpose of this experiment was to investigate the effect of using Azotobacter in reducing chemical nitrogen consumption in bean production in northern Iran.

In order to investigate the effect of using Azotobacter and nitrogen fertilizer on yield and yield components of bean cultivars as a split plot in a randomize complete block design with three replications was performed in an experimental farm located in Langaroud city in 2017. The main factor includes two bean cultivars including: = V1 native and = V2 modified Doroud 4803 and sub-factor 6 levels of nitrogen fertilizer and bacteria: = F1 control, F2 = 50 kg N / ha, F3 = 100 kg N / ha, F4 = Application Azotobacter, F5 = Azotobacter + 25 kg N / ha and F6 = Azotobacter + 50 kg N / ha.

The results showed that the effect of cultivar on number of pods in main branch, number of pods in sub-branch, number of seeds per plant, 100-seed weight, seed yield, biological yield, harvest index, plant height and number of leaves per plant were significant. Different levels of fertilizer on the number of pods in the main branch, number of pods in the sub-branch, number of seeds per pod, number of seeds per plant, 100-seed weight, seed yield, biological yield, harvest index, plant height and number of leaves per plant were significant. The interaction between cultivar and fertilizer on pod number per branch, number of seeds per plant, 100-seed weight, seed yield and harvest index was significant. Treatment F3 (100 kg N / ha) and F6 treatment (50 kg N / ha + Azotobacter) in the studied traits showed superiority over other treatments. Seed yield with application of 100 kg / ha nitrogen (F3) and 50 kg N / ha + Azotobacter (F6) were 2585 and 2455 kg / ha in Doroud cultivar, respectively, which increased seed yield by 68% and 66% compared to the control treatment (F1).

According to the results of the study, the highest seed yield was obtained in the improved Doroud cultivar with an average of 2585kg / ha in treatment of 100 kg N / ha and was in one statistical group with application of 50 kg N / ha + Azotobacter. In fact, it is possible to reduce environmental pollution by consuming 50% less nitrogen fertilizer and using inoculation with Azotobacter. Therefore, inoculation treatment with Azotobacter and 50 kg N / ha is the most suitable fertilizer treatment for beans in the experimental area.

management of water consumption and fertilizer resources are one of the important factors in the success of cultivation of medicinal plants. So, identification of fertilizers compatible with nature and suitable for plants can have favorable effects on quantitative and qualitative indicators of plants. The Matricaria chamomilla L. is one of the medicinal plants that its use dates back to ancient Roman civilization. In order to investigate the effect of some chemical, biological and animal fertilizers on the physiological characteristics of Matricaria chamomilla under water stress, an experiment was conducted in a randomized complete block design with three replications in the research farm of the Faculty of Agriculture, Urmia University.

Experimental treatments include different levels of irrigation (I) as the first factor at three levels: irrigation after 40 mm evaporation from pan (I1), irrigation after 80 mm evaporation from pan (I2) and irrigation after 120 mm Evaporation meter from pan (I3) and soil fertilizers (F) as the second factor in five levels: no fertilizer (F0), chemical fertilizer (F1), biofertilizer (F2), animal manure (F3) and poultry manure (F4) were. Measured physiological properties included photosynthetic pigment content, relative moisture content, total soluble carbohydrates, percentage of nitrogen, phosphorus and potassium, content of antioxidant compounds, percentage and yield of essential oil and yield of dried flowers, each by standard method was measured.

The results showed that with a delay in irrigation the percentage of nitrogen and phosphorus decreased, while the application of low water stress increased the amount of essential oil and the highest amount of essential oil and essential oil yield were observed in moderate stress conditions. Meanwhile, the highest percentage of nitrogen, phosphorus and the amount of essential oil and essential oil yield were obtained in the application of poultry manure. Application of different fertilizer sources in comparison with the control showed a significant effect on increasing the content of photosynthetic pigments, relative moisture content of leaves, water-soluble carbohydrates and potassium uptake in each irrigation condition. The content of total phenol, flavonoids, percentage of radical inhibition of DPPH and dry yield of Matricaria chamomilla flowers increased by 36, 25, 35 and 24% in optimal irrigation conditions and 30, 19, 30 and 20% in moderate stress conditions and 20, 11, 13% and 17% were observed in severely water stress conditions in plants treated with poultry manure compared to the control treatment respectively.

Based on the results, it can be concloude that in each of the water stress levels, the use of organic fertilizer is more effective in improving the quantitative and qualitative characteristics of Matricaria chamomilla and it is better to increase the efficiency of agricultural products from organic and biological inputs instead of use chemical fertilizers with the aim of reducing pollution and achieve sustainable agriculture.

Licorice (Glycyrrhiza glabra L.) is a perennial medicinal plant which its root and rhizome extract broadly use for food and pharmaceutical industries. Considering the necessity of its domestication as an alternative approach for its wild collection, this experiment was counducted to investigate the effect of electrical conductivity (EC) of nutrient solution on growth and yield of three licorice ecotypes under hydroponic culture.

the experiment was conducted as factorial based on randomized complete block design with three replications in Research Greenhouse of Department of Horticultural Science and Landscape Engineering, University of Tehran in 2018. Treatments were included four levels of electrical conductivity (EC) of nutrient solution (1.5, 2, 2.5 and 3 dS.m-1) and three licorice ecotypes (Baft and Lalehzar from Kerman province and Eqlid from Fars province). In this study, some morphophysiological traits such as plant height and diameter, main stem diameter, number of lateral branches per plant, internode length, leaf area, root length and diameter, root and shoot fresh and dry weight and some biochemical traits such as Chlorophyll index, total phenol content and total antioxidant activity were measured.

the results showed that there was a significant difference between ecotypes on all studied traits except total phenol and total antioxidant activity. Also, different levels of electrical conductivity significantly affected the studied traits, except for root dry weight and total phenol. The interaction effect of both treatments was significant in terms of the morphophysiological and biochemical traits. In each of the three ecotypes studied, with increasing the electrical conductivity of the nutrient solution, plant height and diameter, internode length, leaf area and root diameter showed a decreasing trend. The highest dry weight of shoots was observed in Baft ecotype from Kerman with electrical conductivity levels of 1.5 and 2 dS.m-1 (4.51 and 4.91 g.plant-1, respectively) and Eghlid ecotype from Fars with electrical conductivity of 2.5 dS.m-1 (4.91 g.plant-1). Also, Baft ecotype from Kerman showed the highest dry weight of root (16.02 g.plant-1) in electrical conductivity of 3 dS.m-1. In terms of biochemical traits, the highest amount of chlorophyll index was observed in Lalehzar ecotype from Kerman and electrical conductivity level of 2.5 dS.m-1. The highest amount of total phenol and percentage of antioxidant activity was related to Lalehzar ecotype at the electrical conductivity level of 3 dS.m-1.

according to the results, Baft ecotype from Kerman province and then Eqlid from Fars province in range of electrical conductivity level of 1.5-2 dS.m-1 performed better while in terms of quality criteria, Lalehzar ecotype from Kerman showed the highest amount in electrical conductivity of 3 dS.m-1 compared to other treatments.