Mahmoud, A. A.( 2014). Effect of potassium humate and fulvic acids addition with urea formaldehyde on some soil characteristics and yields productivity of sesame and wheat crops under different irrigation systemEgypt . J. of Appl. Sci., 29 (9) 2014 949-968
Abstract: Using organic acids as soil conditioners like potassium humate and fulvic acids that may be considered a specific management for improving soil properties which can adverse crops productivity. Also, the efficiency of nitrogen fertilizer can be increased through the use of slow release nitrogen fertilizer forms, which reduce the total amount of nitrogen needed, number of fertilizing application, and cost of producing process and finally improve the efficiency of plant recovery and yield. To maximize the benefit of the two cases.
To achieve the previous target, a successive field experiments were carried out soil at Ismailia, Agricultural Research Station in El-Ismailia Governorates (Longitude of 25 o 56 - East and latitude of 54o 26- North, land elevation 16 m). Summer season (2012) using Sesame (Sesamum indicum L., var. Shandawel 3) and winter season (2012- 2013) using wheat (Triticum astivum L, Giza 164) to study the effect of urea formaldehyde as slow release nitrogen fertilizer at four rates from the recommended dose for nitrogen (zero , 50, 75, 100 %) a combined with potassium humate and fulvic acids at one rate (3 %) under two irrigation systems ( drip and sprinkler) on some soil characteristics, yields productively. and nutritional status of plants.
Results revealed that both sesame and wheat yields and there total content of macronutrients were positively significant as compared to the other test treatments when received the four rate of urea form (UF) in presence of potassium humate. Application of low rate of U.F combined with fulvic acids generally was inferior compared by potassium humate.
Also, these results indicate that there are positive relationships between OM, EC, N, P and K in soil with dry matter and N, P and K uptake in sesame and wheat yield at different treatments.
In conclusion, the application of organic acids as soil conditioners like potassium humate, fulvic acids and slow release nitrogen fertilizer as urea form (UF) in combination were the best treatments, as compared to application of treatment only, for improve the sandy soil characteristics and reflected on yield components along with total content of macronutrients, nitrogen especially, under conditions of experiment
Keywords: (potassium humate, fulvic acids, urea - formaldehyde, drip and sprinkler irrigation, residual effect, Sesame and wheat yields. )
