Response of Barley Plants to Potassium Spraying under Water Deficit Conditions

Abstract

A field experiment was carried out at the Experimental Farm of Sakha Agricultural Research Station during the winter season of 2014/2015 and 2015/2016 to study the impact of foliar application with potassium on growth, yield, its components and the economic yield as well as on irrigation water productivity of barley Giza 126 cultivar under water deficit conditions. The experiment was laid out in spilt plot design with four replications. The main plots were designated to irrigation treatments i.e. I 0 = full irrigation (control), I 1 = two irrigations at 35 and 70 days after sowing (DAS), and I 2 = one irrigation at 35 days after sowing (DAS), while the sub plots were devoted to four treatments of foliar application with potassium (K 0 = without spray, K 1 = 1% K 2 O, K 2 = 2 % K 2 O and K 3 = 3% K 2 O) in the form of potassium sulfate (48%). Results showed that, increasing water stress significantly retard photosynthetic pigments, flag leaf area, relative water content (RWC %), yield and its components and carbohydrate content. On the other hand, plants under water stress showed marked increase in grain protein content. Foliar spraying with potassium markedly increased most growth and yield parameters and quality of barley grains. The results showed that high irrigation water productivity (IWP) is attainable without significant yield penalty (utilizing a two irrigations at 35 and 70 days after sowing (DAS), or one irrigation after 35 DAS and foliar spraying with potassium (1% K 2 O, or 2 % K 2 O, or 3 % K 2 O) offering chance for improving land level water use and enhancing the crop economic return.

Impact of different sowing dates and irrigation levels on NPK absorption, yield and water use efficiency of maize

“…This is evident in the increased accumulation of K observed on date 3 under Ir 100 and Ir 70 . Similar observations have been reported in previous studies [61][62][63] , although the relationship between K uptake and temperature has a threshold point. For instance 64 , mentioned that the threshold point was at 25 °C, and with further increases in temperature, K uptake decreased.…”

The impacts of climatic changes on the yield and water use efficiency of maize grown under different sowing dates and two irrigation schemes in arid climate

“…This is re ected in the recorded increases of the K accumulations in date3 under the implementation of Ir100 & Ir70. This observation was reported by previous literature [34,35,36] although the relationship between the uptake K and temperature has a threshold point. For example, [37] mention that the threshold point was at 25 oc, and with the continuous raises in the temperature, the uptake of K decreased.…”