El-Dissoky, R. A.; Dalia A. Sayed and Amal El-Guibali( 2016). Potassium fertilization, compost and bio- fertilizer for improving potato productivity , its quality and profitability in sand soil.Menoufiya J. of Soil Sci., Vol. 1: 21-35.
Abstract: Nutrient management become more important to be discussed to obtain optimum yield with maximum profitability, So, two field experiments were conducted in spilt plot design at El-Sharawy village in EL-Bostan area – Noubaria Region, Elbehera governorate (Latitude 30° 43' 22.01" N, Longitude 30° 16' 44.50" E) during the winter growing seasons of 2014 and 2015 on potato (c.v. spunta), to evaluate the effect of organic manure at two rates (10 and 20 m3 compost fed-1) with or without seed potato inoculation with potassium release bacteria (KRB) "Bacillus circulans" (Org1, Org1+Bio, Org2 and Org2+Bio ), four K treatments (K1: 96 kg K2O fed-1 as K-sulfate (SOP), K2: 48 kg K2O fed-1 as SOP+ 1% K2O foliar as SOP, K3: 48 kg K2O fed-1 as feldspar (FDS) + 1% K2O foliar and K4: 24 kg K2O fed-1 as FDS+ 1% K2O foliar) and their interactions on potato yield and quality. Results reveal that addition of different K-treatments as SOP or FDS with foliar spray of 1% K2O significantly affected shoot fresh and dry weights, tuber yield and its quality parameters (specific gravity, starch and carbohydrate %) and NPK-uptake in favor of SOP. Also, the values of plant growth parameters, tuber yield, tuber quality parameters and NPK-uptake were increased with increasing compost rate from 10 to 20 m3 fed-1 along with KRB inoculation. Interaction between Org2+Bio and K2 produced the highest values of tuber yield (16.697 t fed-1) and NPK-uptake, whereas, higher values of tuber quality parameters were recorded under interactions of (Org1+Bio*K2 or K3) and (Org2+Bio*K2 or K3). For economic evaluation, results showed that K2 and K3 treatments along with 10 m3 compost fed-1+Bio were superior for net return (NR) and investment factor (IF), since the highest values of NR and IF were 11247 L.E fed-1 and 1.93 with interaction Org1+Bio*K3.
Keywords: (potassium, feldspar, compost, K-releases bacteria, sandy soil, potato yield and its quality, NPK-uptake economic evaluation)
