EFFECT OF NPK FERTILIZATION ON YIELD OFMAIZE AND POTATO

Abstract

ABSTRACT
Two field experiments were conducted at the College of Agriculture, University of Baghdad in a silty clay loam soil .The 1st trial included five combinations of elements N-P-K 0-0-0,100-100-100,200-100-100,200-100-200, and 300-100-200 Kg ha-1, and two irrigation scheduling regimes by application of water when 50 and 75 of available water depletion and maize plants were used as plant indicator. The 2nd trial included three combinations of elements N-P-K 0-0-0,100-100-100, and 200-100-200, Kg ha' with potato used as plant indicator. Results of the 1 st trial indicated that significanteffecl of nutrient applied on plant height. The treatment 200-100-200 gave the best results with 7.3% increase lin, plant height compared to control treatment. Pi ant height was higher in the 75% compared to 50% water depletion treatment. Neither nuuient combinations nor water regimes alone gave any significant differences effects on dry matter yield and grain yield. However, there was 3 significant interaction effect on grain yield with control treatment at 50% water depletion giving best results (250 gm plant'). The results of 2nd trial indicated significant effect of nutrients application on potato tuber yield with treatment 200-100-2UO giving showed a highest yield with 20,16 ton ha•1, It was concluded that crop genus, soil type, method of irrigation, and surrounding environmental conditions have affected plant responses to treatments applied .. However, generally speaking the treatment 200-100-200 was almost the best treatment in both trials in terms of plant height of maize and grain and tuber yield of maize and potato respectively. The lacks of clear cut response to water regime treatments in the 1 st trial signify the rationalization of water applications especially for spring sawn corn crop.