Response of Maize Plants to Skip Irrigation and Nano Potassium Treatments in Salty Soil

A field experiment was conducted in Maamirah, Babylon, ( 33-32 north latitude and 45-42 east longitude), 10 km south of Hilla, Iraq, in loam clay soil in the fall 2018 season to study the effect of skip irrigation and potassium fertilizer treatments on maize yield. A split plot arrangement within a randomized complete block design with three replications was used. The main plots included three irrigation treatments( control (S0), skip one irrigation at eight leaves-stage (S1) and skip irrigation at silk stage (S2), while sub-plots included 6 potassium treatments, control without adding K fertilizer (K0 ), adding potassium fertilizer recommendation of 50 kg K.ha-1 (K1) to the soil, spraying of nano K fertilizer (2000 mg per liter) (K2), Spraying 1500 mg of nano potassium + soil K fertilizer of 12.5 kg.ha-1 (K3), Spraying 1000 mg of nano potassium + soil K fertilizer of 25 kg.ha-1 (K4), and spraying 500 mg per liter of nano potassium + soil K fertilizer of 27.5 kg.ha-1 (K5). The results indicated that skip irrigation caused a significant reduction in plant height, plant leaf number, chlorophyll, plant leaf area, N, P and K percentages in leaf, and prolin content compared to control. Skip irrigation at 8 leaves stage was more effective in decreasing plant leaf number, chlorophyll, plant leaf area, leaf N percentage, and prolin compared to skip irrigation at the silk stage. Potassium fertilizer caused a significant effect on plant height, plant leaf area, chlorophyll, leaf N, P, and K percentage, and prolin content. In general, the effect of spraying nano-potash and its combinations with mineral fertilizer did not differ from the recommendation for mineral fertilizer.