Management of pH water used in nutrient solution on strawberry yield strawberry cv. Diamant.

Introduction
The Fe iron significantly affects the quantity and quality of agricultural production. Factors affecting the absorption of this element increase its efficiency. Meanwhile, the pH of the nutrient solution plays an important role in iron absorption. Iron is one of the essential elements for plant growth and plays an essential role in chloroplasts. Due to iron deficiency, the activity of several enzymes such as catalase, cytochrome oxidase, and ferroxin is significantly reduced. The amount of iron in the soil is high, but plants only absorb two-capacity of soluble soil, which is negligible compared to the total iron. Soil environmental conditions affect the amount of iron by the plant, so it is difficult to control the uptake of iron by the plant. It has the highest ability to absorb iron and manganese at a pH less than six. For this reason, acetic acid was used to stabilize the pH of the solution. Acetic acid has all the properties of an acid. Acetic acid is a polar solvent and an organic compound. The use of inexpensive organic acid and citric acid in agriculture, despite its positive effects on calcareous soils and their reasonable price, is still not common in Iran. Acetic acid has a carboxylic group and therefore has all the properties of an acid.
 
Materials and Methods
The pH solution plays a role in absorbing iron elements. This experiment was carried out in the form of a split-split plot in a randomized complete block design on a strawberry plant of diamant cultivar in the research station of the University of Mohaghegh Ardabili during the years 2015-2017. Ardabil City in northwest Iran is located between Sablan and Baghrou mountain ranges. Due to its high altitude and mountainous nature, this city is colder than other cities in Iran and is considered one of the semi-arid cold regions. The average rainfall of this city is reported to be 400 mm. Factors included acetic acid (zero, one, two, and three percent), iron in two levels (sequestration 25 gr and nano one gr), and two levels of agricultural soap agents (zero and 7.5 %) as foliar spraying. Foliar application of pH nutrient solution from the three-leaf stage of the plant (mid-April) to the end of May, a total of five times 10 days apart in both years, was done. Two weeks after the last foliar application (June of the second year) plant growth indices included leaf fresh and dry weight, root fresh and dry weight. Root length, flower-to-fruit ratio, chlorophyll greenery a, b, and total, leaf iron content and fruit yield per plant were measured.
 
Results and Discussion
The results of the analysis of variance showed that the three-way effect of treatments in all studied traits except root length and yield at one percent probability level on leaf fresh weight, leaf dry weight, and chlorophyll a, b and total at five percent probability level on fresh weight and root dryness, flower to fruit ratio and leaf iron content were statistically significant. The three-way interaction of acetic acid, iron, and agricultural soap data showed that the highest leaf fresh weight, leaf dry weight, root fresh weight, root dry weight, ratio of flowers to fruits, chlorophyll b, total chlorophyll and the amount of leaf iron related to the treatment acetic acid two percent of sequestration iron in combination with agricultural soap (7.5 %) and in chlorophyll a, it was related to the treatment of acetic acid one percent of sequestrin iron in combination with agricultural soap. The lowest amount of fresh and dry weight of leaves, fresh root weight and dry root, flower-to-fruit ratio, and leaf iron content were related to the treatment of acetic acid zero with Nano iron with agricultural soap (control). The lowest Chlorophyll b and total chlorophyll were related to the treatment of acetic Acid three percent with Nano iron with agricultural soap (control). In addition, the interaction between acetic acid and iron at the level of five percent probability on root length and yield was significant.
 
Conclusion
It can be concluded that acetic acid two percent on the absorption of iron fertilizer, along with agricultural soap (7.5 %) application, has better results than other treatments and qualitative traits of strawberry fruit. In general, it can be concluded that the pH of the nutrient iron solution can improve plant growth and crop yield. The iron level of sequestration iron with two percent acetic acid with agricultural soap 7.5 % due to increasing the bicarbonate of the soil in the Ardabil region has caused the absorption of nutrient elements, especially iron by strawberries. The shelf life of the solution on the leaf surface had a more favorable effect on most growth indices in the strawberry Diamant cultivar in Ardabil soil conditions.