INTRODUCTION Maize belongs to cereal crops that grow all around the world and is fit for human and animal consumption. Millions of people get energy from it and ranked second cereal crop after rice in the world (World Agriculture Production, 2016). In Pakistan maize enjoys third position next to wheat and rice. Starch, protein, oil, fiber, sugar and ash contribute to maize grain 71, 11, 4.9, 5.7, 3.1 and 1.6 percent, respectively (Chuudhary, 1993). Due to its photo-thermic property, maize is known as “Queen of cereal” and propagated throughout the year (Verma, 2011). Many important products are formed from maize like fiber, dextrin, malto glucose and gluten harvests which are being used commercially as oil, pharmaceutical, paper, textile, maquillages, alcohol and poultry feedstuff (Khan, 2007). Water is being most important gift of the world serves to mankind and plants by providing them inhabitation like sea, river and pond. Crop plants absorb water almost ninety percent of its weight and then transport it to all over plant body helping the minerals uptake from soil to plant shoots including leaves and stems, providing turgor pressure and support to the plant (Capon, 2010). Water takes part in photosynthesis reaction and gives us glucose in combination of carbon dioxide. Now a days, Pakistan is facing water shortage issue because of violation of Indus water treaty and less dams. So, there is need to conserve water for future usage for human as well as for crop plants (Baranyiova et al., 2010). Irrigation scheduling help us to conserve water and give us net returns by saving charges on fertilizers applied as well as on applied water and it increases the quality of crops. Several verified irrigation scheduling methods have been presented to save water and net return (Stone et al., 2001). Maize water requirement varies with different ecological conditions and soil type. Fortnight application of water to maize crop can enhance its water use efficiency leading to maximal yield obtained from drought during growing season. Normally, through fast growing period maize has higher water requirement. Depending upon the favourable climatic conditions maximum maize crop production can be achieved through normally 600 to 700 mm of water. When water availability is beaten by evapotranspiration at any stage then maize crop yield is decreased. Crop plant becomes more susceptible to diseases and insect pest attacks after getting nutrient deficiency resulted from moisture shortage (Reddy, 2006). Normally, Pakistan’s soils have great dimensions to deliver accessible K to crops beneath regular environment but J. Glob. Innov. Agric. Soc. Sci., 2019, 7(3):135-139. ISSN (Online): 2311-3839; ISSN (Print): 2312-5225 DOI: https://doi.org/10.22194/JGIASS/7.872 http://www.jgiass.com GROWTH AND YIELD RESPONSE OF SPRING MAIZE (Zea mays L.) UNDER DIFFERENT POTASSIUM DOSES AND IRRIGATION REGIMES Inzamam-ul-haq 1,* , Muhammad Shahbaz Naeem 1 , Rana Muhammad Amir 3 , Muhammad Ilyas 1 , Faisal Shabir 1 , Ibrar Ahmad 2 , Bahaar Ali 2 , Zia Farid 1 and Hafiz Ali Raza 3 1 Department of Agronomy, University of Agriculture Faisalabad, Pakistan; 2 Department of Plant Breeding and Genetics, Islamia University Bahawalpur, Pakistan; 3 Institute of Agri. Extension & Rural Development, University of Agriculture Faisalabad, Pakistan * Corresponding author’s e-mail: razaa0617@gmail.com A field experiment was carried out to evaluate the effect of different potassium doses and irrigation regimes on growth and yield responses of spring maizeat Faisalabad in spring, 2016. It was comprised of three replications with net plot size 3 × 6 m. The treatments were irrigation regimes (Full irrigation (Control), Skip irrigation at vegetative growth stage, Skip irrigation at vegetative growth stage and grain filling stage) and potassium levels (0, 130, 163, 195 kg ha -1 ). Murate of Potash (M.O.P) was used as the source of potassium. All other agronomic practices were kept normal and constant for all treatments excluding the factors under study. Data on growth, yield and quality parameters were recorded by following standard procedures. The data was analyzed by using Fisher’s analysis of variance technique and the difference between the treatment means was compared by least significant difference (LSD) test at 5% probability level. The results show that maximum plant height at maturity (209.44 cm), stem diameter (2.11 cm), cob length (20.75 cm), cob diameter (4.09 cm), number of grain rows per cob (15.70), number of grains per cob (471.42), grains weight per cob (140.80 g), 1000-grain weight (275.89 g), economic yield (8.23t ha -1 ), Stover yield (8.23t ha -1 ), biological yield (19.34t ha -1 ), crop growth rate (23.71 g m -2 day -1 ) and maximum seed oil and protein contents was 4.60% and 8.11%, respectively. It is concluded that potassium should be applied @195 kg ha -1 to get maximum yield of maize under drought stress. Keywords: Drought stress, irrigation regimes, potassium doses, flowering stage, yield.