جستجوی مقالات مرتبط با کلیدواژه « رنگدانه فتوسنتزی » در نشریات گروه « زراعت »

Japanese barberry (Berberis thunbergii) is a perennial and woody shrub that grows in different regions of Iran and the world. The Berberidaceae family has a high potential in food and pharmaceutical industries due to its antioxidant, antimicrobial and anticancer activities. Elicitors are biotic or abiotic stimulators that can induce responses in plants. Abiotic elicitors are used to increase secondary metabolites in plants. Nanoparticles have minimum dimensions between one and 100 nanometers, which have specific physical and chemical properties. Like many nanoparticles, zinc oxide and cerium dioxide nanoparticles are toxic to living organisms. The mechanism of toxicity of nanoparticles is generally contributed to the induction of oxidative stress which lead to the formation of free radicals. Nanoparticles of zinc oxide and cerium dioxide can increase the antioxidant capacity of plants by stimulating oxidative stress. 

In order to study the changes in the physiological and biochemical characteristics of Japanese barberry under the influence of abiotic elicitors, an experiment was conducted in a completely randomized design with three replications in the greenhouse and laboratory of the Faculty of Agriculture and Natural Resources of Imam Khomeini International University in 2019. Treatments were included zinc oxide elicitors (0.1 g/L) and cerium dioxide nanoparticles (0.0002 g/L) and control (no elicitor). In this research, the amounts of protein, antioxidant enzymes and photosynthetic pigments in tissues of Japanese barberry were measured. Data analysis was done with SAS 9.1.3 statistical software. Comparison of means was done with Duncan's multiple range test and graphs were drawn using Excel software. 

The results of the data analysis of variance showed that the effect of treatment with cerium dioxide and zinc oxide nanoparticle elicitors on the amount of leaf protein, antioxidant activity and also the amount of photosynthetic pigments was significant. Comparison of the means showed that these two elicitors increased the leaf protein content by 26.2% and 12.4%, respectively, compared to the control, but they did not have a significant effect on the root protein content. Cerium dioxide decreased the activity of guaiacol peroxidase enzyme by 77.1% in the root; But in leaves, the activity of this enzyme increased by 134.8% due to treatment with zinc oxide. The highest activity of leaf superoxide dismutase enzyme (25.2% increase compared to control) was related to zinc oxide treatment. The lowest content of catalase enzyme in leaves and roots was obtained with cerium dioxide and zinc oxide. Zinc oxide increased the activity of leaf ascorbate peroxidase enzyme by 111.8%; In the root, the highest and lowest activity levels of this enzyme were obtained in the control and cerium dioxide treatments, respectively. Both elicitors significantly increased the leaf peroxidase enzyme activity compared to the control (128.6% and 157.1%, respectively); However, only the treatment with zinc oxide caused a significant increase of 25.5% in the activity of this enzyme in the root. The highest activity of glutathione reductase enzyme in leaf and root was observed in zinc oxide treatment (23.3% and 12.5% increase compared to control). Nano zinc oxide increased the amount of total chlorophyll and carotenoid in the leaves compared to the control by 93.4 and 67.5%, respectively. 

It was concluded that zinc oxide nanoparticles elicitor had the greatest effect in increasing the amount of photosynthetic pigments and enzyme activity. By using this elicitor in Japanese barberry culture, the amount of antioxidant enzymes can be increased and the extract can be used as a strong antioxidant in pharmaceutical products.
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The aim of this study was to investigate the effect of leaching on the reduction of soybean (Glycin max), black cumin (Nigella sativa), dill (Anethum graveolens) and dragonhead (Dracocephalum moldavica) residues allelopathy in wheat (Triticum aestivum) cropping. The experiment was conducted in a completely randomized design with three replications in 2017. The factors consisted of four types of previous plants (soybean, black cumin, dragonhead and dill) and three levels of leaching (without leaching, once leaching and twice leaching). The results showed that the previous plant type and leaching levels had no significant effect on wheat emergence. Leaching reduced the effects of deterioration of soybean, black cumin, dragonhead and dill. The highest rate of emergence was observed with 1.73 seedlings per day for wheat cultivated in soil with dill and dragonhead residues plus once leaching. The greatest root length (24.7 cm) was associated with wheat grown in soils with dragonhead residues plus once leaching. The highest leaf area and chlorophyll a and chlorophyll b content observed in the wheat grown in the soil with soybean residues plus once leaching. It was concluded that in agroecosystems where autumn wheat is in rotation, it is necessary to avoid wheat cultivation in the presence of soybean, black cumin, and dragonhead and dill residues and to reduce the inhibitory effects of these plants, one stage of leaching must be done before the cultivation of wheat.

To investigate the effect of foliar application of micronutrients on chlorophyll and protein content and yield of alfalafa populations and evaluate economics obtain cost- effect, an experiment was carried out in split split plot by time with four replications using a randomized complete blocks desighn at the Shahid Zendeh-Ruh Agricultural Research Center of Kerman. Experimental treatments were micronutrients with five levels: Fe, Zn, Mn, Fe+Zn+Mn and control (without nutrient applications), bacterial inoculation, with three levels: Rhizobium melilloti, Rhizobium legumenasarum</em> and without inoculation. Foliar application had a positive significant effect on all traits under study and increased chlorophyll and protein contents, and alfalfa forage yeild. The highest fresh forage yield belonged to second cutting (71 t.ha-1</sup>) by using combined micronutrient foliar application and to third cutting (68 t.ha-1</sup>) by using Rhizobium</em> leguminosarum</em>. The highest protein rate was observed in Mn foliar application and Rhizobium meliloti</em> inoculation at second cutting by 50%. Based on the results obtained it can be concluded that foliar application of micronutrients and inoculation with Rhizobium </em>bacteria improves morphological characteristics of Bami population of alfalfa in Kerman region.

IntroductionGarlic is the second and the most commonly used plant after onion from allium which is very important according to the food value because of its medical and mineral properties. On the other hand, macro nutrients such as nitrogen can cause better accumulation of dry matter with the development of leaf area and the efficient use of solar radiation and distribute it in the leaves and shoots. The usage of organic fertilizers such as cow manure is one of the most important nutritional strategies in the sustainable management in agricultural ecosystems.
Materials and MethodsThe experiment was carried out in a randomized complete block design with three replications, at the research farm of agricultural college of Shahrekord University in 2015. Treatments consisted of N100P, N150P , and N200P (100,150, and 200 kg N/ha in the form of urea phosphorus requirement, respectively); N100PS, N150PS , and N200PS (100, 150, and 200 kg N/ha in the form of urea phosphorus requirement sulfur requirement, respectively); BCM100, BCM100, and BCM100 ((100, 150, and 200 kg N/ha in the form of cow manure as broadcast application); SCM100, SCM100, and SCM100 ((100, 150, and 200 kg N/ha in the form of cow manure as subsurface application). In this experiment, chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, dry weight of leaf, plant height (38 , 68 and 98 days after planting ), number clove per plant, clove weight and garlic yield were measured. All analyses were performed based as randomized complete block design. The data was analyzed using one-way ANOVA and mean comparison was performed by LSD test. The F-test was considered significant at p Results and DiscussionThe results showed that the effects of fertilization treatments on chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, dry weight of leaf, plant height (38, 68 and 98 days after planting), number of clove plant and clove weight were significant. Treatment of 150 kg N/ha in the form of urea plus sulfur with an average of 3.66 mg/g was the highest amount of chlorophyll a but it did not have significant difference with BCM100 treatment. Additionally, the formation of chlorophyll b in garlic with the use of organic fertilizer (BCM100 treatment) is similar to those of which 50 kg per hectare more nitrogen was used in the form urea fertilizer. Total chlorophyll of whole plots receiving organic manures decreased by 10.5% compared with chemical fertilizers, also organic treatments BCM200 and SCM200 did not have significant difference for total chlorophyll. Based on these comparisons, the amount of total chlorophyll of sulfur treatments was by 5.81 higher than treatments with lack of sulfur. Carotenoids in cow manure treatment (SCM100 and SCM150) with 100 kg N/ha in the form of urea did not have significant difference. But the amount of carotenoids of other organic and chemical treatments compared with these treatments significantly decreased. For plant height (38 days after planting) in BCM100 (10.86 cm) and BCM200 (11.83 cm) treatment did not show a significant difference with the SCM100 and SCM200 treatments. The plant height (68 days after planting) in N100PS with an average of 34.3 cm had a significant increase compared with other fertilizing treatments. Differences of receiving plots of organic fertilizers compared with chemical fertilizers for leaf dry weight has a decrease of 16.3%. Chemical treatments (N200P and N200PS with the average of 9965 and 9715 kg per hectare, respectively) had the highest yield, as well as subsurface application could increase the mean of yield by 5.63 percent in compared with the broadcast application.
ConclusionsIn general it can be concluded which the subsurface application of cow manures in compared to broadcast application had the highest amount of garlic production. Also, in the highest level of nitrogen fertilizer (200 kg nitrogen per hectare), the highest yield was obtained with treatments of chemical fertilizers. However at the level of 150 kg nitrogen per hectare, manure particularly subsurface application was superior to other nitrogen resources. Thus, in order to reduce the use of chemical fertilizers in agricultural ecosystems, subsurface application of manure is recommended to suitable produce garlic plant, but if the goal is to achieve the maximum yield of garlic bulb at least 200 kg N ha-1 in the form of chemical fertilizer is required.

In order to study the effect of biological fertilizer and microelements on chlorophyll content, protein percentage and grain yield of chickpea (Cicer arietinum L.) as affected by drought stress condition an experiment carried out in factorial based on complete block design with three replications in 2014 at Agricultural Research Station of Roudehen of Islamic Azad University in Damavand. Treatments were three levels of drought stress: normal irrigation (control), stress at flowering stage and stress in early stages of grain filling and the second factor was four levels of biological fertilizer and microelements including control, biological fertilizer (Rhizobium), microelements, Rhizobium + microelements. Results showed that drought stress had significant impact on chlorophyll content, protein percentage and grain yield. Control treatment (normal irrigation) produced the highest chlorophyll content, protein percentage and grain yield. Impact of biological fertilizer and microelements on all traits were non-significant except protein percentage and grain yield. The interaction effect of drought stress and biological fertilizer and microelements for protein percentage and grain yield was significant.