Introduction: Barley is one of the most important sources of livestock feed and is tolerant to drought and salinity. Salinity of water and soil resources is one of the most important agricultural problems in Iran. In salinity conditions, the availability of nutrients in the soil solution is reduced due to the high concentration of chlorine and sodium ions, which leads to disturbance in the nutrition and upsetting of the balance of plant nutrients. Therefore, the role of proper nutrition in these conditions is very important to help maintain the balance of nutritional elements and provide the proper growth and plant performance (Ahmadi et al., 2006). Due to the reduction of fresh water resources and the increase of fresh water consumption on the other hand, the access to water with suitable quality for agriculture is very limited (Mahlooji et al., 2018). It is obvious that in such conditions, it is inevitable to use water of poor quality for the production of agricultural products. Therefore, the current research was conducted with the aim of studying the effect of chelate and nanozinc solution spraying on the yield and growth indices of three barley cultivars under irrigation water salinity conditions.
Materials and Methods: In order to investigate the effect of irrigation water salinity and foliar application of chelate and zinc nano oxide on yield and some growth indices of barley cultivars, an experiment in the form of a randomized complete block design with arrangement of split blocks with three replications at the station Rodasht salinity research was conducted in Isfahan.Three water irrigation quality including w1=control, 1-2 dS/m (low salinity), W2=10 dS/m (common salinity in the region), W3=18 dS/m (high salinity) were evaluated in vertical factors. The horizontal factors were foliar spraying including (nano zinc-oxide, chelated zinc, mixture of nano and chelated and water spraying as a control). Three different barley including (Morocco as a moderate semi sensitive, Nosrat as a moderate tolerant and Khatam as a tolerant) cultivars spilted within vertical factors. Statistical analyzes and graphs were performed using SAS and Excel software and comparisons of means were performed using LSD test.
Results and Discussion: The results showed that with increasing salinity of irrigation water, grain yield, dry weight (DM), crop growth rate (CGR), leaf area ratio (LAR) and specific leaf area (SLA) decreased. Foliar application of Zinc element compared with no Zinc increased TDM, RGR, CGR, LAR and grain yield. Khatam cultivar was superior to Morocco cultivar due to its DM, RGR, CGR, LAR, SLA and higher grain yield.Among physiological indices, SLA showed a positive and significant correlation with grain yield (r2 = 0.97). Overall, in order to increase plant growth indices as well as grain yield of barley under salinity irrigation water, foliar application of zinc fertilizer and the use of Khatam cultivar (salt-tolerant) is recommended.
Conclusion: In general, the results showed that with increasing irrigation water salinity, grain yield, total dry weight, crop growth rate, leaf area ratio and specific leaf area of ​​barley decreased. Foliar application of zinc element compared to check (control) caused an increase in dry weight, relative growth rate, crop growth rate and leaf area ratio, and grain yield. Khatam variety was more tolerant to salinity due to its dry weight, relative growth rate, product growth rate and leaf area ratio, specific leaf area and grain yield compared to other varieties. It seems that the absorption of zinc from the soil by the plant roots is disturbed in the saline irrigation conditions, so the plant has shown a positive and appropriate reaction to the foliar application of zinc, which ultimately increases the growth and yield. He brought the plant with him. In general, it seems that in order to increase the growth indices and also the yield of barley grain under irrigation water salinity conditions, foliar feeding with zinc fertilizer and the use of Khatam variety are recommended.