Mitigation of water stress by compost and arginine application and its impacts on barley production

Background Water-scarce locations necessitate the deployment of creative and sustainable techniques for managing water for agricultural production. Field experiment was conducted at the Experimental Research Farm of National Research Centre, Nubaria region, Egypt to alleviate the harmful effect of water stress on the yield of Mediterranean barley varieties (Giza 125, Tombari, Ksar Megrine and Tamellat) by compost (0.0, 2.0, 4.0, 6.0-ton fed −1 ) and arginine application (0.00 and 1000 ppm) under deficit irrigation. The amounts of irrigation water applied were “900 and 450” m 3 fed −1 to sufficient irrigation and deficit irrigation, respectively. Results The greatest and most significant values of the chlorophyll values and relative water content values obtained at the treatment supplied with 6.0-ton compost fed −1 and sprayed with Arginine. There was a significant dramatic decrease in proline content with increasing compost application rates and treated barley plants by Arginine for all the studied barley varieties under both studied irrigation treatments. Increasing compost application rate is associated with significant increase in number of spike m −2 without or with arginine. Barley Tombari variety received 6.0-ton compost fed −1 gained changes to give a greatest significant value of grain (ton fed −1 ) under sufficient irrigation and Tamellat under deficit irrigation situation. The significant maximum values of the grain yield (1.96- and 2.09-ton fed −1 ) were attained at Tombari and Tamellat varieties which received 6.0-ton fed −1 compost with or without arginine under sufficient irrigation. The increases in compost rate increment changes to incremented grain yield values with arginine application more than untreated one. The greatest and significant grain yield was found at the treatment received 6.0-ton compost fed −1 with arginine foliar application. Conclusion Compost application has an important role in maintaining greatest water use efficiency for plant and arginine application reported to contribute in reduction in destructive effects of a biotic stress thus their importance in increasing the barley production under water stress.