EFFECT OF SKIP IRRIGATION AND NANO POTASSIUM TREATMENTS ON MAIZE YIELDAli H. Jasim, Sura R. Husain and Hanaa H. Mohammed
A field experiment was carried out in Maamirah area, located at 33-32 north latitude and 45-42 east longitude, 10 km south of Hilla, Iraq, in loam clay soil at fall 2018 season to study the effect of water stress and Potassium fertilizer treatments on maize yield. Split plot arrangement within randomized complete block design with three replications was used. The main plots included three irrigation treatments (control, skip one irrigation at eight leaves-stage (S8) and or at silk stage S silk), while sub plots included 5 potassium treatments, control without adding fertilizer (K0), adding potassium fertilizer recommendation of 50 kg K.ha-1 (as N-P-K :15-15-25, 200 kg.ha-1 ) to the soil (K1), spraying 200 mg of nano potassium (K2), spraying of 1500 mg of nano potassium +50 kg.L-1 potassium fertilizer (K3), spraying 1000 mg.L-1 of nano potassium + 100 kg ha-1 potassium fertilizer (K 4), and spraying 500 mg.L-1 of nano potassium + 150 kg.ha-1of potassium fertilizer (5K). The fertilizer quantity of phosphorus and nitrogen were adjusted to 30 kg P2O5 ha-1 and 100 kg N ha-1 uniformly for all experimental units by adding super phosphate (46% P2O5) and Urea (46% N). The results indicated that spraying 500 mg.l-1 of nano potassium + 150 kg.ha-1 of potassium fertilizer (K5) was superior in grain yield and biological yield ( 7.07 t.ha-1 and 19.29 t.ha-1 , respectively), while spraying of 1500 mg of nano potassium + 50 kg.L-1 potassium fertilizer (K3) gave the highest weight of 100 grains weight (32.3 g). It is clear that spraying of nano-K fertilizer contributed to reduce the plants need for soil potassium fertilizer.