EFFECT OF ORGANIC AND CHEMICAL FERTILIZERS ON GROWTH AND YIELD OF THREE LOCAL POTATO VARIETIES

Abstract

The study was carried out in the field of vegetables/ Department of Horticulture and Landscape Design / Faculty of Agriculture and Forestry / University of Mosul / Iraq during the spring growth season 2018 to study growth and yield of three potato varieties which local produced tubers from last spring season, with addition organic fertilizer: Rice residue and poultry manufactured manure (Italian origin), and chemical fertilizer NP, and control treatment. The experiment involved 12 treatments (3×4) carried out in the field using a split plot system within Randomized Complete Block Design (RCBD) with three replicates. The cultivars were placed in the main plots and fertilizers treatments placed in the sub plots. The results could be summarized as follows: The Volar variety gave the least days for tuber emergence and higher tuber emergence percentage. The sylvana variety significantly increased chlorophyll content in leaves. The Arizona variety increased significantly tuber weight, tuber number per plant, plant yield and tubers total yield 71.05 gm, 9.90 tuber. Plant-1, 707.66 gm. plant-1 and 37.741 t. ha-1 respectively. No significant differences observed between varieties in the yield quality. The addition of chemical fertilizer significantly increased plant higher, tuber weight, tuber number per plant, plant yield and tubers total yield 61.63 cm, 81.54 gm, 10.54 tuber. Plant-1, 859.43 gm. plant-1 and 45.835 t. ha-1 respectively. Poultry manure increased significantly quality yield such as tubers dry matter percentage, starch percentage and specific gravity of tubers. The interaction between volar variety with chemical fertilizer gave least days for tuber emergence. Arizona variety with chemical fertilizer significantly increased plant higher 62.86 cm, tuber weight 83.77 gm, and tuber number 11.76 tuber. Plant-1, plant yield 985.13 gm. plant-1and total yield of tubers 52.540 t. ha-1. Sylvana variety with control increased chlorophyll content in leaves, but Arizona variety with rice residue increased significantly dry matter percentage, starch percentage of tubers and specific gravity of tubers