Evaluation of zeolite application on yield and water use efficiency of maize (Zea mays L.) under deficit irrigation

Maize is the third most important agricultural crop in the world in terms of production, That production and demand has increased by 45% in 2020 compared to 1997. Abiotic stresses in many cultivated areas of this plant have a negative impact on its production and these effects are expected to intensify in the near future.Inefficient use of water in agricultural production in arid and semi-arid regions is one of the most important factors in exacerbating the water crisis and water shortage is a serious limiting factor in agricultural production. The use of technologies to improve water use efficiency in crops is very important for sustainable crop production and food security. Deficit irrigation is a water-saving strategy that is commonly used in arid and semi-arid regions and leads to increased water efficiency. According to studies, Deficit irrigation can save irrigation water, maintain or increase crop production and improve its quality. One of the methods for optimizing water consumption in agriculture is the addition of moisture absorbent such as Zeolite, which by gradually providing absorbed water and nutrients to the soil, play an important role in fertility and preventing water loss. The use of zeolite, especially in sandy soils that exposed to drought stress, can improve growth and final yield by absorbing and controlling moisture release and increasing soil moisture capacity. Because of low rainfall and also limitation of water resources in Birjand region, efficient use of water in agriculture, especially in the production of important cereals such as Miaze, is very important. The aim of this study was to investigate the application of zeolite and deficit irrigation methods for optimal use of water and achieving optimum yield in Maize in this region.

In order to investigate the effect of irrigation and Zeolite on maize, a field experiment was conducted on two planting dates in 2017, factorial based on a randomized complete block design with three replications. The factors including Zeolite in two levels and deficit irrigation in eight levels include: 100% water requirement, 75% water requirement in vegetative stage with: conventional irrigation, Fixed alternate partial root-zone irrigation, nonfixed alternate partial root-zone irrigation, and 75% water requirement in total growth with Fixed alternate partial root-zone irrigation, 50% water requirement in vegetative stage with: conventional irrigation, Fixed alternate partial root-zone irrigation, nonfixed alternate partial root-zone irrigation.

Traits measured on the second date of planting had the highest value compared to the first date. Deficit Irrigation reduced the total dry weight and grain yield, but the use of zeolite improved these indicators. Total dry weight, number of grains per ear, grain yield, harvest index and water use efficiency had the highest value in irrigation control treatment and decreased with deficit irrigation, so that the lowest value in conventional irrigation treatment The basis of 50% of water requirement in the growing season was observed with 23, 26, 38, 27 and 19% reduction, respectively. Zeolite application had a favorable effect on all traits, but the effectiveness of some traits was different during planting dates, so that the rate of yield increase on the second planting date (37%) was higher than the first date (27%). The highest water use efficiency was obtained on the second planting date and Fixed alternate partial root-zone irrigation based on 75% of water requirements during the growing season and total growth with 0.7 and 7.6 due to the increase in observation, had the highest Were the amount. Although the yield decreased in deficit irrigation treatments, but due to the increase in harvest index and water use efficiency, excess water due to under-irrigation can be spent on irrigating more lands and increasing production.

One of the important goals of production in areas with water constraints is to increase the yield per unit of water. According to the results, after the control treatment, the highest harvest index was related to 75% water requirement in vegetative stage with Fixed alternate partial root-zone irrigation treatment. Also, based on water use efficiency, to 75% water requirement in vegetative stage with Fixed alternate partial root-zone irrigation and 75% water requirement in total growth with Fixed alternate partial root-zone irrigation treatments were better than other treatments with a superiority of 0.69 and 7.59% compared to the control treatment. Despite saving 19.84% of water consumption in low irrigation treatments, 50% of water requirement in the growing period, but did not get an acceptable result from this treatment (33.74% reduction in yield and 13.79% efficiency). Water consumption). It seems that the relatively severe lack of water during vegetative growth has caused serious damage to the roots of the plant, which in the later stages of growth, despite the optimal irrigation of the plant could not use the water in the root environment well. Regardless of the reduction in yield and considering the water use efficiency that was obtained in 75 water requirements treatments in the form of atmospheres and constant intermediate stacks in the vegetative period and the whole growth period, it seems that these two treatments for Execution in Birjand region should be more appropriate.