جستجوی مقالات مرتبط با کلیدواژه "نانوتکنولوژی" در نشریات گروه "زراعت"

There is no doubt that significant progress is being made in nanoscience and technology, which has paved the way for advancements in many different fields such as agriculture, biology, food, and medicine. Among the different types of nano-scaled metal oxides, zinc oxide nanoparticles (ZnONPs) are among the most widely employed nano-compounds in various industries, including agriculture, food, and medicine. Nitric oxide (NO) is a bioactive signaling substance in living organisms, including plants, which plays vital roles in different stages of plant development during the life cycle. Physiological responses of crop plants to long-term application of NO or ZnONPs individually and mixed manners have not been well investigated and remain largely unknown. The purpose of this research is to investigate the effect of long-term foliar application of NO or ZnONPs on the growth performance and physiology of tomato plants. Considering the necessity of developing a sustainable agricultural approach, this project was designed to evaluate the effect of long-term foliar application of NO or ZnONPs on the growth, performance, nutrition and metabolism of tomato.

This study was implemented as a completely randomized design with four treatment groups and three independent replications. This experiment was conducted in soilless conditions (cocopeat and perlite) in a greenhouse (Islamic Azad University, Garmsar branch, Garmsar). Tomato seedlings was irrigated with Hoagland nutrient solution. 30-days-old tomato seedlings were sprayed with ZnO-NP at two concentrations (0 and 3 mg/L) or NO (0 and 25 μM) 15 times with an interval of 72 hours.

The results showed that NO and ZnONPs treatments, especially in the combined one, caused a significant increase in the biomass in shoot and root compared to the control. The applied treatments also affected the characteristics of the plants in the reproductive stage. The application of NO and ZnONPs treatments significantly reduced the time of entering into the reproductive phase, increased fruit production, and enhanced fruit biomass, which indicated the effectiveness of these treatments on plant reproductive development. Foliar spraying with NO and ZnONPs caused a significant improvement in the content of several essential minerals, including potassium (K+), iron (Fe) and zinc (Zn) in leaves and fruits, compared to the control group. The NO and ZnONPs treatments synergistically and significantly augmented in the concentrations of photosynthetic pigments, including chlorophyll a (Chl a), chlorophyll b (Chl b), and carotenoids in leaves in comparison to the control group. The highest amount of proline amino acid was observed in ZnONP and NO+ZnONP treatment groups, which was significantly higher than the control group. Single and combined treatments of seedlings with NO and ZnONPs led to a significant increase in the content of soluble phenols in leaves compared to the control group. Phenylalanine ammonialyase (PAL) enzyme activity also followed the same trend as soluble phenols. Also, the activity of antioxidant peroxidase enzyme showed a significant up-regulation in response to the application of NO or ZnONPs. The highest activity of nitrate reductase enzyme was recorded in the leaves of plants simultaneously supplemented with NO and ZnONPs.

The results of this research indicated that foliar spraying with NO or ZnONPs at low concentration can lead to the promotion of plant growth and metabolism and also strengthening the plant's defense system, while reducing the risk of possible toxicity. These findings can be useful for designing future studies on nano-fertilizers or pesticides. This study also emphasizes the necessity of providing transcriptome and proteome data in future studies.

Drought is assumed as one of the most severe abiotic stress factors limiting plant growth and crop production. Drought stress hurts plant growth and productivity which can affect biochemical and physiological responses such as changes in contribution of stem assimilates to grain, current photosynthesis, yield and yield components. Using rhizosphere microorganisms (such as beneficial bacteria and mycorrhiza) (Dimkpa et al. 2009) and application of silicon are an alternative strategy that can improve plant performance under stress environments and, consequently, enhance plant growth through different mechanisms. Thererfore, it seems that application of nano silicon and bio-fertilizers can improve wheat yield under water limitation conditions.

In order to study the effect of bio-fertilizers and foliar application of nano-silicon on the contribution of dry matter remobilization and current photosynthesis in grain yield of wheat under irrigation withholding conditions, a factorial experiment was carried out with three replications at the research farm faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili during 2018-2019. The area is 38° 15′ N latitude, 48° 15′ E longitude, and 1350 m above mean sea level. Climatically, the area is situated in the semi-arid temperate zone with a cold winter and moderate summer. Factors were included irrigation in three levels (full irrigation as control; moderate water limitation or withholding irrigation at 50% of the heading stage; severe water limitation or withholding irrigation at 50% of the booting stage) based on codes 55 and 43 of the BBCH scale; foliar application of nano silicon (foliar application with water as control, 30 and 60 mg.l-1) and bio-fertilizer (no application as control, mycorrhiza application, both application of flavobacterium and pseudomonas, both application of flavobacterium and pseudomonas with mycorrhiza). Mycorrhiza fungi (mosseae) was purchased from the Zist Fanavar Turan Corporation and soils were treated based on method of Gianinazzi et al. (2001). Psedomunas and flovobacterium were isolated from the rhizospheres of wheat by Research Institute of Soil and Water, Tehran, Iran. For inoculation, seeds were coated with gum Arabic as an adhesive and rolled into the suspension of bacteria until uniformly coated. The strains and cell densities of microorganisms used as PGPR in this experiment were 1×108 colony forming units (CFU). In this study, morphological traits, leaf area index, total biomass, dry matter remobilization from shoot and stem, contribution of stem assimilates to grain, contribution current photosynthesis in grain, yield and grain yield components of wheat were investigated. Analysis of variance and mean comparisons were performed using SAS version 9.1 computer software packages. The main effects and interactions were tested using the least significant difference (LSD) test at the 0.05 probability level.

The results showed that both application of mycorrhiza with flavobacterium and pseudomonas under full irrigation conditions decreased the contribution of dry matter remobilization from shoot (27.33%) and stem (17.70%) in grain yield, but increased the current photosynthesis (305.10 g.m-2) and Contribution Current photosynthesis in grain (72.66%). Also, maximum of grain yield (4593 kg.ha-1) and harvest index (38.4%) were obtained with the application of both bio-fertilizers and foliar application of 30 mg.l-1 nano-silicon under normal irrigation. Maximum leaf area index, total biomass, and yield components were obtained with the combined application of bio-fertilizers and 60 mg.L-1 nano-silicon under full irrigation conditions.

Based on the results of this study, it seems that the application of bio-fertilizers and nano-silicon can be a suitable management factor to increase grain yield of wheat under water limitation.

Drought is assumed as one of the most severe abiotic stress factors limiting plant growth and crop production. Since in arid and semi-arid regions, some part of growth period of wheat is confronted with water limitation condition which can affect biochemical and physiological responses such as changes in photosynthetic efficiency of PSII, chlorophyll content, and stomatal conductance. Application of bio fertilizers and silicon is one of the most important strategies for alleviation of drought stress effects. Bio fertilizers (plant growth promoting rhizobacteria or PGPR and mycorrhiza) can improve plant performance under non-stress and stress conditions. Thererfore, it seems that application of nano silicon and bio-fertilizer can improve wheat yield under water limitation conditions.

In order to study the effects of biofertilizers and nanosilicon on phosphorus uptake, grain yield, and some physiological traits of wheat (Triticum aestivum L.) under withholding irrigation conditions, a factorial experiment was carried out at the research farm faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, with three replications during 2018-2019. The area is 38° 15′ N latitude, 48° 15′ E longitude, and 1350 m above mean sea level. Climatically, the area is situated in the semi-arid temperate zone with a cold winter and moderate summer. Factors were included irrigation in three levels (full irrigation as control; moderate water limitation or withholding irrigation at 50% of the heading stage; severe water limitation or withholding irrigation at 50% of the booting stage) based on codes 55 and 43 of the BBCH scale; foliar application of nano silicon (foliar application with water as control, 30 and 60 mg.L-1) and bio-fertilizer (no application as control, mycorrhiza application, both application of flavobacterium and pseudomonas, both application of flavobacterium and pseudomonas with mycorrhiza). Mycorrhiza fungi (mosseae) was purchased from the Zist Fanavar Turan Corporation and soils were treated based on method of Gianinazzi et al. (2001). Psedomunas and flovobacterium were isolated from the rhizospheres of wheat by Research Institute of Soil and Water, Tehran, Iran. For inoculation, seeds were coated with gum Arabic as an adhesive and rolled into the suspension of bacteria until uniformly coated. The strains and cell densities of microorganisms used as PGPR in this experiment were 1×108 colony forming units (CFU). In this study, electrical conductivity, stomatal conductance, leaf fluorescence parameters, phosphorus of root and grain, relative water content, electrolyte leakage, anthocyanins and grain yield of wheat were investigated. Analysis of variance and mean comparisons were performed using SAS ver 9.1 computer software packages. The main effects and interactions were tested using the least significant difference (LSD) test at the 0.05 probability level.

The results showed that application of both flavobacterium and pseudomonas with mycorrhiza and foliar application of 60 mg.L-1 nano silicon under severe water limitation increased 84.32%, 49% and 49.52% of electrolyte leakage, electrical conductivity and minimum fluorescence (F0) respectively, and decreased root and grain phosphorus by 30.67 and 36.05% compared to full irrigation. The highest RWC (92.26%), stomatal conductance (58.86 mmol.m-2.s), anthocyanin (0.0274 µmol.g-1FW), Fm (860), and Fv/Fm (0.909) were obtained at foliar application of 60 mg.L-1 nano silicon, both applications of flavobacterium and pseudomonas with mycorrhiza under normal irrigation. Also, the highest grain yield was obtained with both flavobacterium and pseudomonas with mycorrhiza and foliar application of 30 mg.l-1 nano silicon under normal irrigation. According to the results of this study both the application of biofertilizers and nanosilicon can improve wheat grain yield under water limitation conditions by improving the physiological traits and also the uptake of phosphorus from the soil.

Generally, it seems that application of bio fertilizers and nano silicon can be recommended as the proper method for increasing the physiological trait grain yield of wheat under water limitation conditions.

In order to investigate the effects of nanoparticles and their concentrations on the stages of germination, growth and development of crop plants, experiments were performed using a factorial experiment based on the completely randomized design on guar and chickpea seeds as the Petri dish and pot. In the present study, the effects of different concentrations of zinc and iron nanoparticles (control, 100, 200, and 300 mg.l-1) were examined on seed germination indices in petri dish cultivation and growth, physiological and biochemical traits of the mentioned plants in pot cultivation. The results of the Petri dish experiment showed that the highest percentage of germination, root resistance, and the lowest T50 were obtained under the interaction of chickpeas, iron nanoparticles, 300 mg.l-1. Also, the highest germination rate was obtained for guar and chickpea seeds at a concentration of 300 mg.l-1 of the iron nanoparticle. The results of the pot experiment also showed that the maximum shoot length, dry weight of aerial part and root were achieved for the plant exposed to a concentration of 300 mg.l-1 of zinc nanoparticle. Also, the content of chlorophyll a, total chlorophyll and leaf protein increased by 300 mg.l-1 of zinc nanoparticle. On the other hand, the amount of chlorophyll b and carotenoids increased under a concentration of 300 mg.l-1 of the iron nanoparticle. In general, it is concluded that zinc and iron nanoparticles in the range of concentrations of 100-300 mg.l-1 had positive effects on germination, growth, physiological and biochemical indices of seeds and seedlings of guar and chickpea in these conditions.

To study the effect of water limitation and application of bio-fertilizer and nanosilicon on yield and some biochemical characteristics of wheat, a factorial experiment was carried out in a randomized complete block design with three replications in the research field of Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran, in 2018-2019. Experimental factors were included irrigation in three levels (full irrigation as control and irrigation cut-off at 50% of booting and heading stages, based on codes 55 and 43 of the BBCH scale, as moderate and severe water limitation, respectively,), foliar application of nano-silicon (water spraying as control, 30 mg/L or 22.5 mg/m2  and 60 mg/L or 45 mg/m2 nano-silicon) and bio-fertilizer (no application as control, application of mycorrhiza (Glomus mosseae), application of flavobacterium + pseudomonas strain 186, combined application of mycorrhiza and flavobacterium + pseudomonas). The results showed that the highest antioxidant enzymes activity and soluble sugars were obtained by combined application of bio-fertilizers and foliar application of 30 mg/L nano-silicon under the condition of irrigation limitation at booting stage. Under full irrigation condition and non-application of bio-fertilizers and nano-silicon, the activity of catalase, peroxidase and polyphenol oxidase enzymes and soluble sugar content decreased 78, 49, 64 and 74 percent, respectively, compared to severe water limitation at booting stage and combined application of bio-fertilizers and 30 mg/L nano-silicon. Maximum proline content was also obtained by foliar application of 60 mg/L nano-silicon (9.50 µg/g FW) and combined application of bio-fertilizers (9.70 µg/g FW) under severe stress conditions (10.97 µg g Fw-1). Hydrogen peroxide (H2O2) content under severe water limitation at booting stage and non-application of bio-fertilizers and nano-silicon was 90% higher than the application of 60 mg/L nano-silicon and combined application of bio-fertilizers under full irrigation condition. The highest grain yield (4593 kg/ha) was obtained from the foliar application of 30 mg/L nano-silicon and combined application of bio-fertilizers under full irrigation conditions. The results of current study showed that the combined application of bio-fertilizers and nano-silicon can increase wheat grain yield under water limitation conditions by improving plant biochemical characteristics.

In order to study the effects of foliar application of nitrogen with nano-and urea chemical fertilizers on quantitative and qualitative characteristics of bitter apple, an experiment has been conducted in a randomized complete block design with three replications at the Agricultural Institute, University of Zabol during 2019.Theexperimental treatment includes foliar application of nano-N (1000 and 2000 mg/l), urea (1% and 2%), and control. Results show that foliar application of N has had a significant effect on yield and number of fruit per bush, and shoot length, whereas it has had no effect on fruit average weight, fruit length and diameter. The highest yield per bush belongs to nano-N at 2000 mg/l concentration (961.08g) and urea at 2% concentration (864.66g) and, the highest amount of fruit number per bush (12) is found in nano-N at 2000 mg/l concentration. The highest weight of 100 seeds and seed protein are obtained from the foliar application of nano-N at concentration of 2000 mg/l and urea at 2% concentration. Seed phenol content, seed soluble carbohydrates, and oil percentage have been reduced by applying nitrogen treatments to the control. Foliar application of N has increased leaf N concentration, while having no effect on the leaf concentrations of P, K, and Zn. Given that in most measured quantitative and qualitative traits, the application of nano-N fertilizer at 2000 mg/l concentration shows better results than other treatments, this treatment can be recommended to reduce economic and environmental costs.

In order to study the corn response to the application of various chemical, nano, nano-biological fertilizers and organic extract of seaweed, an experiment was carried out at the research farm of agriculture faculty-Islamic Azad university- Sanandaj branch during 2016-2017. The experiment was conducted as split plot in a completely randomized block design with three replications. The main factor included the application of different fertilizers in six levels (control, chemical fertilizer, nano fertilizer, nano-biological fertilizer, combination of 50% chemical fertilizer + nano fertilizer, combination of 50% chemical fertilizer + nano-biological fertilizer) and a sub-factor including application of seaweed extract in two levels (control: distilled water and application of seaweed extract) were considered. The results showed that the effect of fertilization was significant on the characters as: cob length, cob diameter, number of rows per cob, number of seeds per row, 1000 grain weight, grain and biological yield, protein and oil percentage. The highest grain and biological yield were obtained from a combination of 50% chemical fertilizer + nano-fertilizer, which increased 10.52% and 14.85%, respectively in comparison with chemical fertilizer. The effect of seaweed extract on all studied traits was significant, with except to number of cob per plant. The seaweed extract increased the grain and biological yield to 12.48 and 11.66%, respectively. The results of interaction effects on all traits were significant with except to cob number and protein percentage. Finally, the maximum grain and biological yield were obtained from the combination of 50% chemical fertilizer + nano-fertilizer and seaweed.