Effect of Phosphorous, Potassium Nano-Fertilizers and Spraying of (Sepehr 4) Nano-Fertilizer and Carbon Nanotubes on the Growth and Yield of Rice (Oryza sativa L.)

The purpose of this experiment is to compare the growth and yield of the Amber 33 cultivar of rice after being fertilised with nano-phosphorous and nano-potassium, as well as after being sprayed with carbon nanotubes and nano-synthetic fertiliser (Sepehr 4) (K+Fe+Zn+Mn). Between June 15 and November 23, 2022, researchers in Babylon province, Iraq, combed through the area known as District 41-Al-Hussainiya, which is located to the south of the city of Hilla. Using a Randomised Complete Blocks Design (RCBD), two levels of phosphorus and potassium nano-fertilizers (0 and 10 kg.ha-1) were applied to some treatments, while other treatments included spraying with nanomaterials, such as carbon nanotubes (at a concentration of 50 mg L-1) and Sepehr 4 nano-fertilizer (K+Fe+Zn+Mn) (at a concentration of 10 mg L-1). The results of the statistical analysis of the Duncan test showed that the four-component combination (nano-phosphorous+nano-potassium+spraying carbon nanotube+synthetic nano-fertilizer) (K+ e+ Zn+ Mn) recorded the highest values in plant height (134.5) cm and biological yield (20.710) Meg ha-1, grain yield was (6.067) Meg ha-1, the concentration of nitrogen in the grain was (1.40)%, and the percentage of protein in the grain was (8.331)%, and the combined effect was (phosphorus nano-fertilizer+carbon nanotubes +sepehr 4 synthetic nano-fertilizer achieved the highest index of chlorophyll at (42.63) SPAD, The combined effect of the combination (P nano-fertilizer + carbon nanotube +(K+Fe+Zn+Mn)) and Spray Nano(K+Fe+Zn+Mn) solo achieved the highest significant increase in the Clearance % (68,780 and 68,670)%respectively. While spraying the carbon tubes alone achieved the highest field efficiency of (7958.000) kg kg-1


Introduction
Among cereal crops, rice (Oryza sativa) is second only to wheat in importance to Asia as both a staple diet and a global economic driver ]1[.More than 90 percent of the world's rice crop is grown and consumed in Asia and the Pacific ]2 [ .Rice rice is one of the grain crops grown in 114 nations throughout the world, spanning from the tropics to the warm temperate and subtropical zones up to 40 degrees south latitude and 50 degrees north latitude, respectively ]3[.Nanotechnology is a promising technology if it is used scientifically and soundly in the agricultural field, as it reduces the loss of fertilizer nutrients, sedimentation in the soil and environmental pollution.According to nanotechnology, it works with very high efficiency from small amounts of additives, with dimensions 1259 (2023) 012016 IOP Publishing doi:10.1088/1755-1315/1259/1/012016 2 of 1-100 nanometers, which distinguishes it with a high surface area with slow release and smart targeting according to the plant's need for it ]5,4[.It stimulates growth and productivity in quantity and quality, and little is used up when compared with traditional mineral fertilizers, as it is rapidly absorbed, transported and represented within plant tissues and is stable in different conditions ]6[.Nano-phosphorous is one of the nutrients that have a role in biological and chemical reactions in the process of respiration, cell division, nucleic acids, carbon metabolism, disease resistance, resting and root system development ]7[.Nano potassium is also one of the elements that have a role in periods of drought as a result of its participation in the process of opening and closing stomata and thus controls the process of transpiration in the leaves and engraves more than 80 enzymes inside the plant ]8[and the formation of panicles and panicles has a role in it ]9[.Foliar nutration has a positive role on the content of plants of micro and macro nutrients and increases the growth of shoots and improves grain yield and quality.By dissolving it in water and spraying it on the vegetative system, it is absorbed from the epidermis through the stomata on the leaf surfaces to compensate for the deficiency in the elements ]10[, Foliar nutration is no longer a substitute for ground fertilization, but it is considered as a supplement to ground fertilization for the purpose of improving yield and quality ]11[.Spraying rice crops with nano-synthetic fertilizers (K, Mn, Zn, Fe) had an effect on enhancing the synthesis of proteins and photosynthesis, activity of enzymes, regulation of osmosis, opening and closing of stomata, energy transfer, phloem, cation-anion balance and stress resistance in plants ] 12[, and that spraying zinc has a role in activating a number of enzymes, including the enolase enzyme, and it has a role in the formation of chlorophyll, and it has an effect on the fertilization process in plants ] 13[ Manganese, which has a role in the process of oxidation and reduction, and the process of electronic flow of light reactions for the process of photosynthesis of the photolysis of the water molecule ]14[, as well as iron from the elements that activate oxidation and reduction enzymes in the chain of transmission of electrons in the process of respiration, and helps to build chlorophyll Although it is not included in the combination ]15[ and the spraying of carbon nanotubes (CNTs) has an effective and applied role in agriculture through its direct delivery of many nutrients and its easy penetration into the cell wall of any plant ]16[.MWCNT-treated plants led to an increase in crop yield and quality, as it stimulated carbon metabolism in the plant and increased the chlorophyll content of the leaves ]17[ and carbon nanotubes (CNTs), which are hollow cylinders of carbon atoms that appeared as coiled graphite tubes that are in large bundles of single or multiple sheets, and they are of two types, including single-walled (SWCNTs) and multi-walled (MWCNTs) ]18[, Therefore, this study came with the aim of knowing the effect of fertilization with nano-phosphorus and nano-potassium, spraying nano-(N, K, Fe, Zn, Mn) and carbon nanotubes, both individually and jointly, on some growth parameters and rice yield.

Experiment Location
The field research took place in Iraq's Al-Tali'ah district/Babylon province between 15 June 2022 and 19 November 2022, the time frame needed for the rice crop to mature.The coordinates used for the study were N 35 600 50' and E 48 19 07'.

Experiment Design
Randomised complete blocks design (RCBD) was used to conduct the experiment with three replicates, each including sixteen experimental units.Nano-fertilizers of phosphorus and potassium were applied at a rate of 0.10 kg ha -1 , while Sepehr 4 (K, Mn, Zn, Fe) was sprayed at a rate of 2.5 ml L -1 and carbon nanotubes were sprayed at a rate of 50 mg L -1 , each at a rate of four sprays for a total of 48 experimental units.19According to Table 1

Experiment Field Preparations
After designating the experimental field and performing perpendicular tillage, smoothing and levelling on it, soil samples were taken at a depth of 30 cm from five locations, one each on the four field perimeters and in the middle, to serve as a representative sample of the field soil, which is sedimentary soil with a silty clay loam texture and classified as Entisols.In the eyes of the contemporary American taxonomist ]20[.Laboratory analyzes of the soil sample were carried out according to the methods reported by [14], as they included electrical conductivity (EC) = 2.2 ds m -1 (pH) = 7.40.Available nitrogen = 20.55 mg N kg -1 soil, available phosphorus = 13.10 mg P kg -1 soil, available potassium = 200.20 mg K kg -1 soil, organic matter = 12.30 g kg -1 soil.Three independent experiments were conducted in a (300) square metre field, each with 16 identical plots (3 x 1.5 = 4.5 m 2 ), and waterways were dug to irrigate the panels (experimental units) and culverts were installed to collect runoff.

Implantation and Crop Service
On 6/15/2022, 120 kg of H -1 seeds were sowed using the scattering method directly on the preprepared soil and then covered with dirt to prevent erosion with water.These seeds were certified by the Rice Research Station in the Al-Mishkhab district of the Al-Najaf province.Watering and avian snatching.Starting with the irrigation of germination and continuing through the grafting stage (1-3/8/2022), the soil was irrigated and the irrigation process was continued (every 3 days), with the irrigation water depth being maintained at about 10 cm to ensure the availability of the appropriate amount of water required for plant growth up to the stage of full maturity of plants.In addition to constant hand weeding, the irrigation water was turned off 15 days before harvest.

Fertilization
Before the planting date, two doses of nano phosphorus fertiliser (0.10 kg ha -1 ) were mixed into the soil and applied (Table 2).The doses were determined by the area of the experimental unit.Before planting, the soil was amended with two different amounts of nano potassium fertiliser (0 and 10 kg ha -1 ; Table 2), with the amounts calculated based on the area of the experimental unit.Foliar fertilization (spraying): The nanomaterials, including carbon nanotubes, were sprayed at a concentration of 50 mg L -1 and the quadruple nano-synthetic fertilizer Sepehr 4 (K+Fe+Zn+Mn) at a concentration of 2.5 mg L -1 per spray, four sprays of each Nano-material before flowering and 50% flowering, with a difference of 14 days between one spray and another.According to the fertilizer manufacturer's instructions, by foliar spraying on the vegetative of the plant by (400 liters ha -1 ) (Table 2).The central laboratory of the Department of Physics at the University of Tehran used FE-SEM scanning electron microscopy to measure the size of nano-phosphorous and nano-potassium particles, confirming that their sizes fell inside the nanoscale range (1-100 nanometers).

Harvest
The rice crop was harvested on 11/19/2022 when all plants reached full maturity and the grain moisture content ranged between 18-25% ]21[.

Plant Height (cm)
At 100% flowering, ten plants were randomly selected from each experimental unit and their heights were measured from the soil surface to the top of the plant.The average was then calculated by dividing the total plant heights by the total number of plants ]22[.

Leaf Chlorophyll Index (SPAD)
Obtaining a rough estimation of leaf chlorophyll content in real time in the field through the use of a portable SPAD-502 chlorophyll metre prior to the flowering stage of plants ]23[.Ten plants from each experimental unit had their leaves sampled, and the mean was calculated by dividing the total content of the leaves by the total number of leaves.

Biological Yield (Meg ha -1 )
After air drying for 10 days, we weighed the sample to determine the biological yield, which we then converted to milligrammes per hectare based on the total dry matter above the soil's surface from the harvested plants within the specified square metre of each experimental unit ]24[.

Grain Yield (Meg ha -1 )
After 10 days of air drying, the harvested plants' grain output was evaluated within the square metre of each experimental unit.The Multi-grain device at the Seed Examination and Certification Department in the Diwaniyah Governorate of Iraq recorded the grain yield in kilogrammes per square metre, which was then mathematically converted to micrograms per hectare at a moisture content of 14% ]24[.

Weight of 1000 Grains (g)
A multi-grain device in the Field Crops Department / College of Agriculture / University of Babylon estimated the weight of 1000 grains for each treatment based on the count of 1000 grains, and then the grains were weighed using an electronic scale (measuring from 100 mg to 1 kg) based on moisture content of 14%.

Nitrogen in Grains %
The nitrogen concentration was estimated according to the method ]25[, and by applying the equation below, the nitrogen concentration was estimated: Nitrogen% = 100/(Weight of the digested sample) × (total volume of the sample)/(volume used for estimation) × (equivalent weight of nitrogen x its molarity × volume of consumed acid)/1000 2.7.8.The Percentage of Protein in Grains % 2 gm was taken from a crushed and dried sample of grains and digested according to the method of ]25[, then the percentage of nitrogen was estimated by the Caldal apparatus, then the protein percentage was estimated according to the following equation: Protein (%) = Nitrogen (%) x 5.95

Clearance Percentage
In the laboratory at the Hilla rice silo, 100 grammes of alabaster grain were crushed using a Japanesemade laboratory grinder.The resulting raw rice was then placed in a Japanese-made laboratory stone Satake Husking rice machine) in order to obtain crunchy rice (bleached) (satake milling rice machine) ]26[, The percentage of ginning = weight of bleached rice (g) / weight of rice grains (gm) x 100

Agronomic Efficiency A.E kg kg -1
The following formula was used to determine the fertiliser productivity, also known as agronomic efficiency ]27[: A.E (kg kg -1 ) = (grain yield in the fertilized treatment -grain yield in the comparison treatment) / (The amount of fertilizer sprinkled or added to the soil per hectare)

Statistical Analysis
Results data was statistically analysed using the Analysis of Variance test from the Analysis ToolPak package found in the scheduling program's add-ons, and significant differences in the average coefficients were determined using the Duncan least significant difference test (P≤0.05).In light of the information provided in ]19[.

Results
According to table (3), the combined quadruple treatment of ((N-P+K) + (CNT) + (K+Fe+Zn+Mn)) resulted in the tallest plants, with a height of (134,500) cm.We observe that all treatments offered a substantial difference compared to (124,600) cm, although it did not exhibit a significant difference with the two treatments N-(P+K)+Spray (CNT) and (N-(P+K)+N-(K+Fe+Zn+Mn)), which amounted to (133.00 and 133.100) cm respectively.

The Chlorophyll Value SPAD
Based on the results shown in Table (3), it was determined that the treatment (N-P+(CNT) +N-(K+Fe+Zn+Mn) excelled in terms of SPAD, with a value of (42.630) compared to (37.500) for the comparative treatment.When compared to (41.370.SPAD), the quadruple treatment (N-K) failed to show a statistically significant difference.

Grain Yield Meg ha -1
The control treatment, at 3.243 Meg ha -1 , produced the lowest grain yield of all the treatments, while the quadruple co-treatment, at 6.067 Meg ha -1 , produced the highest yield of all the treatments.However, there was no statistically significant difference between this treatment and the treatment of N-(P+K)+N-(K+Fe+Zn+Mn), at 5.272 Meg ha -1 .

Weight of 1000 g
There were no significant differences in this trait due to the different treatments.

Harvest Index %
According to Table (4), the difference in the treatments did not achieve any significant difference between them in the quality of the harvest index.

Clearance Percentage %
As indicated by the results of Table (4), the treatment Spray carbon nanotubes (CNT) amounting to (63.540)% did not rise to the level of significance compared to the control (65.070)%, as well as the two treatments (N-P + (CNT) + N-(K+Fe+Zn+Mn))) and (Spray Nano(K+Fe+Zn+Mn)), which reached (68.780 and 68.670)%, did not show any significant difference between them, while they were significantly superior to the rest of the experimental treatments.

Agronomic Efficiency kg kg -1
The treatment (Spray carbon nanotubes (CNT)) amounting to (7958) kg kg -1 gave the highest agronomic efficiency, which was significantly excelled on all treatments, Table (4).
Table 4. Effect of fertilization of nano-phosphorous , nano potassium and spraying with carbon nanotubes and Sepehr 4 synthetic nano-fertilizer on the weight of 1000 grains gm, the percentage of nitrogen and protein in the grains, the percentage of clearens %, and the agronomic efficiency kg kg -1 .

Discussion
Through the results in Table (3), it was found that the increase in plant height as a result of the addition of phosphorus , potassium nano-fertilizers and spraying carbon tubes , nano-synthetic fertilizer (K+ e+ Zn+Mn) had a significant effect on stimulating the growth parameters of the rice crop, where the nanomaterials possess A very large surface area that stimulates growth, increases photosynthesis, and increases plant tolerance to biotic and abiotic stresses ]5[, phosphorus has a role in disease resistance, resting, respiration, and cell division ]7[ and that the increase in the index of chlorophyll SPAD when spraying nanomaterials and adding nano-phosphorus and nano-potassium is due to the high efficiency of nanomaterials in stimulating the activity of some enzymes and their rates and increases chlorophyll synthesis and photosynthesis]28,29[.Phosphorus works to strengthen the stems, early flowering, seed formation and development, increase the length and density of roots, increase root hairs, and resistance to braking ]7[.Also, spraying carbon nanotubes works to increase chlorophyll content and photosynthetic activity ]17[, and spraying with nano-synthetic fertilizer (K+Fe+Zn+Mn) containing potassium may stimulate the ability of plant leaves to carry out the process of photosynthesis, as a decrease in The level of potassium in plants has an effect on building the ATP compound, which is the main carrier of energy in the plant and a storehouse for it to represent CO 2 (30).Manganese is a catalyst for the activities of more than (35) enzymes in the plant and produces chlorophyll, although it does not participate in the composition ]31[.Iron has an auxiliary role in the formation of chlorophyll ]32[.The role of nanomaterials in expanding the surface area of enzymatic reactions and activities and facilitating nutrient absorption from leaves and soil is also observed, along with an increase in biological yield and grain when spraying nanomaterials and adding nanoparticles and potassium ]33[.Phosphorus is effective in increasing crop productivity, and it has a role through biochemical reactions in the process of respiration, cell division, nucleic acid formation, and carbon metabolism ]7[.As for grain yield, spraying with nanomaterials and fertilizing with nano-phosphorus and nanopotassium led to an increase in grain yield ]34,35[ and the increase in the productivity of crop grains when fertilizing with potassium nanopotassium, because potassium has an effective role in stimulating more than 80 enzymes towards the formation of starch for the storage organs, as well as participates in the process of photosynthesis and its distribution of carbohydrates ]36,37,38[.Through the contrast of the results of table 4, we notice the percentage of nitrogen in the grain, spraying with nanomaterials and adding phosphorous and potassium nano-fertilizers led to a significant increase in the proportion of nitrogen and the increase in the percentage of protein in the grains.by the roots and leaves, which led to an increase in the nitrogen content of the leaves ]6[.As for the clearance % by spraying with nano-fertilizer (K+Fe+Zn+Mn) and carbon nanotubes and their combinations they stimulated the emergence and development of grains in a good and integrated way, because these fertilizers have effective elements in strengthening the biological enrichment and thus improving the quality, as zinc has important roles in the formation of enzymes And protein substances, which have a role in protecting plant tissues from oxidative stress ]39[,Manganese also stimulates the processes of oxidation, reduction and photosynthesis ]14[, and iron is involved in the formation of ferredoxin and important cytochromes in photosynthesis and respiration.It also has a role in the formation of protein as a result of its nitrate reduction ]32[.The spraying of carbon nanotubes (CNTs) stimulated the plant to regulate the effectiveness of the leaves in absorption by increasing the efficiency of stomata with longer and more sufficient roots, which led to faster growth and facilitated the absorption of water and nutrients, and thus increased crop yield, quantity and quality, and photosynthetic activity ]17[, As for the agronomic efficiency, it increased significantly when spraying carbon nanotubes, as it works at very low concentrations of 50 mg L -1 with its active role and its easy penetration into the cell wall of any plant, and thus it can be used as a direct delivery system for many fertilizers ]16[, The ability to collect more light energy increases through the chloroplast ]41[.

Conclusions
Most notably, we found that applying common ground fertilisers and spraying with nanomaterials (phosphorous and nano-potassium fertiliser, carbon nanotubes, and nano fertiliser (K+Fe+Zn+Mn)) resulted in the greatest statistically significant increase in the averages of the traits studied in the rice plant.The combined effect of terrestrial and spraying applications considerably improved plant height, biological yield, grain production, nitrogen content in grains, and protein percentage.As a result, many of the Anbar 33 rice crop's growth metrics were enhanced thanks to the chance to supply integrated plant nutrition.Because of their high yield and targeted nature, these combinations can assist reduce the use of conventional fertilisers on crops.

Table 1 .
attached.Fertilizers used in the experiment and their components.

Table 2 .
Fertilization experiment treatments and spraying of nanomaterials.

Table 3 .
Effect of fertilization of nano-phosphorus and potassium and spraying with carbon nanotubes and nano-fertilizer (K+Fe+Zn+Mn) on plant height cm, chlorophyll index SPAD, biological yield Meg ha -1 , grain yield Meg ha -1 and harvest index (%).