RESPONSE OF POTATO TO FULVIC ACID AND INORGANIC FERTILIZERS Nuclear Institute for Food and Agriculture, G.T. Road, Tarnab, Peshawar, Pakistan

Abstract

Increasing crop yield through balanced use of fertilizers in conjunction with organic acids is a need of the time to curtail the use of costly chemical fertilizers as well as to minimize the environmental pollution in Pakistan. Fulvic acid (FA) has potential to improve plant growth and yield. Fulvic acid (C₁₄H₁₂O₈) is an acid created in soils due to action of microbes on decaying plant materials under aerobic conditions. Zinc is reported to improve potato yield. The response of potato (Solanum tuberosum L.) has not been investigated in planned field experiments to the foliar application of fulvic acid alone as well as in combination with chemical fertilizers and zinc.  To bridge this research gap, a field experiment was conducted at the experimental farm (clay loam soil) of Nuclear Institute for Food and Agriculture (NIFA), Peshawar, Pakistan. The experiment was laid out in randomized complete block design with seven treatments and three replicates. Treatments included control, NPK @ 150-100-50 kg ha^-1, fulvic acid (150 ppm), ZnSO₄ (2.5 kg ha^-1) + FA (150 ppm), ZnSO₄ (5 kg ha^-1) + FA (150 ppm), 1/2 NPK+ FA (150 ppm) + ZnSO₄ (2.5 kg ha^-1) and 1/2 NPK+ FA (150 ppm) + ZnSO₄ (5 kg ha^-1). Results indicated that fulvic acid may be a good substitute for chemical fertilizers in future as relatively higher yield was attained in treatments receiving fulvic acid in conjunction with zinc and half of the recommended NPK doses. Further comprehensive long term studies are required to develop recommendations for end-users.