The Effect of Planting Dates and Spraying with Boron and Sulfur on Raising the Yield Efficiency of Maize (Zea mays L.)

A field experiment was carried out during the spring period of the agricultural season 2022 AD at a research station of the Department of Field Crops, College of Agriculture - University of Tikrit in Salah al-Din Governorate, located at longitude 43.679 degrees east and latitude 34.616 degrees north of the equator in gypsum soil, in order to know the effect of different planting dates. With three datesThe first date (15/3), the second date (5/4), and the third date (25/4). And add boron and sulfur before flowering by spraying on the plant (boron 50 mg L in the form of boric acid, sulfur 25 mg L in the form of liquid sulfate, boron + sulfur). Its effect on the number of ears, the number of ear beans, the number of its rows, the weight of 300 seeds, the biological yield, the total grain yield, the protein percentage and the ash percentage of the yellow corn cultivar (Sara), using the randomized complete block design (RCBD) with three replications, as each experimental unit included four lines and the length of the line was 3 m and the distance between lineAnd the last 0.75 cm, and between one plant and another 20 cm, and to study the characteristics of growth, yield, its components, and quality characteristics. The first date was superior in all the studied traits except for the following traits: the number of earwigs and the percentage of ash, and there were no significant differences. We conclude from the fertilizer additions the superiority of the addition (sulfur and boron), and it gave the highest averages in the characteristics of the number of ears, the number of ear seeds, the number of rows, the weight of 300 seeds, the biological yield, and the total grain yield, as it reached 1.68 ears, 441.33 ears, 15.00 ear rows, 69.94 g, and 7.94 ton e and 12.69 ton e respectively, outperformingThe addition of boron as a percentage of protein is 11.93% and the percentage of ash is 1.27%. The combination (planting dates + fertilizer additions (first date × sulfur and boron) gave the highest averages in the characteristics of ear number, number of ear pods, number of rows, weight of 300 seeds, total grain yield, and biological yield. for ashes.


Introduction
Yellow corn (Zea mays L.) is one of the most important grain crops, as it is widely cultivated in the world, and its importance has been increasing steadily as a result of the development of highly productive hybrids and synthetic varieties, so it has become the third crop in the world after wheat and rice in terms of area and production.Its grains are used as human food and manufacturing Beverages and biofuels as well.It is used as fodder for animals, especially in feeding cows and poultry.It is used in several industrial fields, such as starch and the manufacture of glues, asbestos, ceramics and 1259 (2023) 012098 IOP Publishing doi:10.1088/1755-1315/1259/1/012098 2 plastics.As for oil, in addition to its use as food, it is also used in varnish dyes and the rubber industry.[1] The grain yield of yellow corn in Iraq when planted in the spring season is characterized by its low production compared to the yield of the autumn season, because the high temperatures and low relative humidity associated with the increase in daylight hours and thus the increase in exposure to high temperatures affect the pollination processes.And fertilization, an increase in the percentage of empty earwigs is noted in this loop.The importance of boron comes due to its close association with cell division and development in the growth areas of the plant near the growing apices of the root and stem as well.Attract insectspollinator [2].Boron plays a vital role in improving the efficiency of transporting nutrients and water from the roots to the rest of the shoots.Tucker [3] indicated that the assimilation and transport of carbohydrates through the membranes towards the meristematic regions of the root and stem is one of the main roles of boron in plants.It also plays a major role in stimulating meristematic tissues, increasing cell division, and the production of growth hormones such as auxins and cytokines [4] Secondary nutrients in general and sulfur in particular have a major role in increasing grain production.Sulfur is increasingly recognized as the fourth major plant nutrient after nitrogen, phosphorus and potassium.It is an essential element of importance in the formation of proteins and strains along with nitrogen and phosphorus.It also plays a major role in chlorophyll formation and oil synthesis.The amount of sulfur requirement for optimal growth ranges between0.1 and 0.5% based on the dry weight of the plants [5].As for the importance of sulfur for plant growth, it lies in the fact that it enters into the formation of protein through the formation of the following amino acids Cysteine, ystine and Methionine, and that sulfur is the most important source for plants in the soil because it is the only form that plants absorb [6].The aim of this study is to try to solve the aforementioned problem by using different planting dates and adding boron and sulfur before flowering by spraying on the plant, as boron has a great role in supporting the reproductive organs of the plant, but sulfur can also help support the nutritional status of the plant.

Materials and Methods
This study includes two factors:

Second -Foliar Fertilization
 (without addition).(0 mg.L). Boron 50 mg.L in the form of boric acid. Sulfur 25 mg.L in the form of liquid sulphur.

Experimental Design and Studied Factors
Randomized complete block design was used with three replications.The cultivar (Sarah) was used, which is a synthetic cultivar exported (Agricultural Research Department / Ministry of Agriculture).The land was prepared for cultivation by plowing it with a two-disk plow orthogonally, then leveling the experimental land and dividing the field into three main sectors, each sector included on 3 unitsExperimental, the area of each unit was (3×3) with 4 lines in each board, the length of the line was 3 m, the distance between one line and another was 75 cm, and between one plant and another was 20 cm.The experiment was planted according to the aforementioned dates.Urea fertilizer (46%) N was used at a rate of 400 kg / h as a source of nitrogen.The first batch was added at planting, the second after a month of planting, and the third at the beginning of the formation of silk according to the level used.The triple calcium superphosphate fertilizer was added 46% P2O5 at a rate of 200 kg / ha batchOne after tilling and before smoothing.Use diazinon granular 10% effective substance at a rate of 4 kg / ha to control the corn stalk borer (Sesamiacretica).Control after the plant height reaches 3 20 cm.Feed the plants by placing one teaspoon for each plant above the growing apex.Data were taken for ten plants guarded from the midlines randomly for each experimental unit after full maturity, and the following studies were conducted on them.

Statistical Analysis
The data were analyzed statistically using the computer and based on the SAS/STAT program, and the averages were compared according to [7] multinomial test.

Studied Traits
Characteristics of the product and its components:  The number of cobs/plant: It was calculated from the average number of cobs of five plants, which were taken at random. The number of grains per ear: It was calculated by multiplying the average number of rows per ear by the average number of grains per row for ten ears of each experimental unit. Number of rows per ear: It was calculated from the average number of rows of grain for ten ears of each experimental unit. The weight of (300) grains: It was calculated from mixing the ten harvested earwigs from each experimental unit, then weighing (300) grains in grams, then adjusting the weight on the basis of 14% moisture.[8]. Total grain yield (ton H -1 ).

Protein Percentage (%)
The percentage of protein was estimated according to the method [9] using the Inframatic device equipped by Perten located in the General Company for Grain Processing, which is the reflection of infrared rays (NIR) [10].And that is (by taking 15) grams of the previously prepared flour sample and placing it in a small cube-shaped container located within the device, and the device is operated, as it gives results within a few minutes.If another sample is used, clean the container with a brush and work again.

Ash Content (%)
The ash content of the flour was estimated by following the standard method No. (0.8-0.1) [9]by burning 5 grams of flour at a temperature of 6000 C for 5 hours.A Gallenhamp Tactical 308 Muffle Furnace was used for this purpose until white color appeared.grayish or until weight stabilizes.

The Effect of Planting Dates and Spraying with Boron and Sulfur on the Yield Characteristics of Yellow Corn
The results of the analysis of variance contained in Appendix (1) indicated that there were significant effects of the planting dates and fertilizer additions and the bilateral interaction between them.%, either adjective a numberearwigs in the plant and the percentage of ash did not reach the significant limit.As for the fertilizer additions, they had a significant effect at the probability level of 1% for all the studied traits.As for the effect of the overlap between planting dates and fertilizer additions, it was significant for the characteristic of protein percentage at the level of probability 1%, and it was significant for the traits number of grains per ear, weight of 300 grains, and grain yield at the level of probability 5%, while the rest of the traits did not reach the limits of significance.

The Number of Cobs in the Plant
The origin of the cob is found archaeologically under the armpit of each leaf in most of the genotypes of maize, and when there is an abundance of growth factors and a lack of plant density, many plants produce two or more cobs [12].The results of Table (1) indicate that there are no significant differences in the characteristic of the number of plant stems between planting dates.It is noted from the same table that spraying boron and sulfur together led to a significant increase in this characteristic compared to the comparison treatment, as this addition excelled and gave the highest average of 1.68 plant ears, and the comparison treatment gave the lowest average of 1.00 plant ears, and it did not differ significantly from the third addition.As for the overlap between sowing dates with fertilizer additions, it was noted that there were significant differences in this trait, as the overlap between the fourth addition (sulfur and boron) with other sowing dates was superior and gave the highest mean for the trait which reached (1.73, 1.66, 1.66) ear nuts.plant, and did not differ significantly from the second addition in the first and second dates, compared to the comparison treatment with all dates, which gave the lowest value for the trait amounted to (1.00) ear.plants.
Table 1.The effect of planting dates and spraying with boron and sulfur on the number of cocoons.

The Number of Grains in the Ear
The characteristic of the number of grains in the main ear is one of the important characteristics that are affected first by the genotypes and then by the environmental conditions secondly.The results of Table (2) indicated that there were significant differences in the characteristic of the number of grains per ear between the sowing dates.It was noticed that the first date excelled and gave the highest average of 361.50 seeds.Arnous, compared to the second and third appointments, which gave him the two lowest averages for the trait, which amounted to (325.41, 313.08) grains.coarse.It is also noted from the same table that there are significant differences between the fertilizer additives for this characteristic, where the fourth addition (sulfur and boron) excelled and gave the highest value for the trait amounted to 33.441 grains.coarse.Compared to the comparison treatment without addition, which gave the lowest mean for the trait, which amounted to 00.263 grains.coarse.It was observed that there were significant differences in this trait, as the interaction between the fourth addition (sulfur and boron) with the first sowing date exceeded and gave the highest mean for the trait amounted to (461.33) seeds.cob,compared to the comparison treatment with the second date, which gave the lowest value for the trait amounted to (229.00).His love.Arnos.

The Number of Rows Per Ear
The number of rows per ear is an important factor in increasing the number of grains, which depends mainly on the percentage of pollination and fertilization, which are two genetic traits that may be affected relatively by environmental factors [12].The results of Table (3) showed that there were significant differences between the sowing dates in this trait, and the first date showed the highest number of rows per ear, which reached (13.66) rows.Arnous did not differ significantly from the second date, while it differed significantly from the third date and gave the lowest average number of rows per ear reached (12.16) rows.coarseAs shown in the same table, there are significant differences between the fertilizer additions for this trait, where the fourth addition (sulfur and boron) excelled and gave the highest value for the trait amounted to 00.15 row.coarse.Compared to the comparison treatment without addition, which gave the lowest mean for the trait, which reached 66.11 rows.coarse.The results of the same table indicate that there are significant differences in this trait, as the interaction between the fourth addition (sulfur and boron) with the first and second sowing dates exceeded, and gave the highest mean for the trait amounted to (15.66, 15.33) row.Arnous, compared to the comparison treatment with the third appointment, which gave the lowest value for the trait, amounting to (10.66) rows coarse.Table 3.The effect of planting dates and spraying with boron and sulfur on the number of rows per cob.

Weighs 300 Grains (gm)
The weight of 300 grains depends on the strength of the source, the capacity of the downstream, and its fullness, the rate and duration of processing the manufactured foodstuffs during the period from flowering to physiological maturity [13].The results of Table (4) indicate that there are significant differences between the sowing dates for this trait, and the first date showed the highest mean of (66.17) gm, while it differed significantly from the third date and gave the lowest average of (63.54) gm for the trait.As shown in the same table, there are significant differences between fertilizer additions for this characteristic, where the fourth addition (sulfur and boron) excelled and gave the highest value for the trait amounted to 18.69 g.Compared to the control treatment without addition, which gave the lowest mean for the trait, which was 14.60 g.The results of table (4) showed that there were significant differences in this trait, as the interaction between the fourth addition (sulfur and boron) with the first sowing date exceeded and gave the highest mean for the trait amounted to (55.71) gm, compared to the comparison treatment with the third date, which gave the lowest value for the trait amounted to (55.83) gm.

Grain Yield kg. Hectare
The characteristic of grain yield, ton/ha, is the final result of all vital processes.The results of Table (5), which show the effect of sowing dates on the grain yield (ton. e) To a significant superiority of the first date (7.04) tons.e,and it did not differ significantly from the second date, which amounted to (6.91) tons.e., while it differed significantly from the third date and gave the lowest mean for the trait, which amounted to (6.64) tons.e.As shown in the same table, there are significant differences between the fertilizer additions for this characteristic, where the fourth addition (sulfur and boron) excelled and gave the highest value for the trait amounted to 94.7 tons.e.Compared to the comparison treatment without addition, which gave the lowest mean for the trait, which amounted to 13.6 tons.It was observed that there were significant differences in this trait, as the interaction between the fourth addition (sulfur and boron) with the first and second sowing dates was superior and gave it the two highest averages for the trait amounted to (8.17, 8.04) tons.e,compared to the comparison treatment with all dates, which gave the lowest value.For the adjective, it reached (6.09, 6.21, 6.10) tons.Table 5.The effect of planting dates and spraying with boron and sulfur on grain yield (TN.H).

Biological Yield (tons .H -1 )
It is the total dry matter produced by the plant during its life cycle, which is represented by stems, leaves, ears and their grains.The biological yield is affected by genetic factors and crop management factors.The results of Table (6) show the effect of planting dates on the biological yield (tons. e) To a significant superiority of the first date (11.97) tons.e,and it did not differ significantly from the second date, which amounted to (11.94) tons.e., while it differed significantly from the third date and gave the lowest mean for the trait amounted to (11.01) tons.e.As shown in the same table, there are significant differences between the fertilizer additions for this characteristic, where the fourth addition (sulfur and boron) excelled and gave the highest value for the trait amounted to 69.12 tons.e.Compared to the comparison treatment without addition, which gave the lowest mean for the trait, which amounted to 60.10 tons.It also found significant differences in this trait, where the interaction between the fourth addition (sulfur and boron) with the first planting date was superior and gave the highest mean for the trait amounted to (13.78) tons e, compared to the comparison treatment with all dates, which gave the lowest value for the trait amounted to ( This class is of great importance and many studies have been conducted on it due to its great connection with the grain manufacturing process, and the aim is to obtain high-quality products of bread and pastries.The percentage of protein in flour is affected by many genetic and environmental factors and the provision of nutrients to the plant [9].The results of Table (7), which shows the effect of sowing dates on the characteristic of the protein percentage, showed that the first date was significantly superior to the second and third dates, as the first date achieved the highest protein percentage of (12.05%) compared to the protein percentage of the second date, which amounted to (10.87%).Boron spraying led to a significant increase in the percentage of protein in the grain compared to the comparison treatment as shown in Table (7).The second addition (boron) was superior and gave the highest value for the trait amounted to 20.12%.Compared to the comparison treatment without addition, which gave the lowest mean for the trait amounted to 14.10%.As shown in the same table, there are significant differences in this trait, where the overlap between the second addition (Boron) with the first planting date was superior and gave the highest mean for the trait amounted to (13.20)%, compared to the comparison treatment with all dates, which gave the lowest value for the trait amounted to (9.93)., 10.13,10.36)%.Table 7.The effect of planting dates and spraying with boron and sulfur on the protein content (%).

Ash Percentage (%)
The percentage of ash in the grains reflects the mineral elements contained in the grains that were absorbed by the plant and turned into grains, which is an important characteristic of flour.Among the fertilizer additions to this.The trait, where the second addition (boron) excelled and gave the highest value of the trait amounted to 47.1%.Compared to the comparison treatment without addition, which gave the lowest mean for the trait amounted to 17.1%.As shown in the same table, there are significant differences in this trait, where the overlap between the second addition (Boron) with the first and second sowing date was superior and gave it the two highest averages for the trait amounted to (1.53, 1.45)%, compared to the comparison treatment with all dates, which gave the lowest value.For adjective it was (1.16, 1.19, 1.17)%.

Conclusions
 The possibility of reducing the negative effect of high temperatures during the pollination and fertilization phase on the grain yield of the yellow corn crop when planted in the spring season by spraying the elements sulfur and boron. The first date was significantly superior in most traits and gave it the highest values for traits (number of ears, number of rows per ear, weight of 300 grains, number of grains per ear, grain yield (kg.H -1 ). The response of yellow maize to spraying with sulfur concentrations of 25 mg L and boron 50 mg L in a significant way.

Recommendations
 To achieve the highest increases in the studied properties, a combination of sulfur and boron can be recommended. Recommend spraying sulfur at a concentration of 25 mg L and boron 50 mg L, with higher concentrations being tested to find out the response of maize plants to these increases. I suggest adopting the first date for planting yellow corn in the spring, as it led to an increase in the characteristics of the yield and its component

Table 2 .
The effect of planting dates and spraying with boron and sulfur on the number of grains per cob.

Table 4 .
The effect of planting dates and spraying with boron and sulfur on the weight of 300 grains (mg).

Table 6 .
The effect of planting dates and spraying with boron and sulfur on the biological yield.

Table 8 .
The effect of planting dates and spraying with boron and sulfur on the character of the ashpercentage (%).Annex 1. Contrast table Reply with the average boxes for studied attributes.