A study was conducted to assess the nutrient release pattern from different liquid manures such as cow urine, panchagavya, fish amino acid (FAA), jeevamrutha, and vermiwash after 0, 7, 15, 45 or 60 days of incubation. The incubated soil was collected from a model organic farm that was managed by the Department of Soil Science and Agricultural Chemistry, College of Agriculture, Vellayani. The study consisted of six treatments including soil alone and soil treated separately with a 10% dilution of each liquid organic manure. All the treatments were maintained at 60% moisture level.
In experiments, increased pH and EC values were observed in all the treatments that received diluted liquid organic manure compared to control. For the release of N and P during incubation, soil along with 10% FAA showed the highest release pattern whereas soil along with 10% cow urine recorded the highest K release throughout the incubation period. There was an increased release of Ca in the liquid organic manure treatments. The highest Mg release throughout the incubation period was observed with 10% cow urine. The available iron content was higher in T5 (5 kg soil + 10% jeevamrutha) compared to other treatments. There were increasing trends in the Cu content of soil from day 0 to day 60 of incubation, except for T3 (5 kg soil + 10% FAA).
It was concluded that in liquid organic manures, Fish amino acid followed by cow urine has given the best result with respect to nutrient release.