Collembola
organic farming
organic manure
effective microorganisms
nutrient mineralization
carrots
carbon and nitrogen isotope analysis
disease-suppressive soil theory
organic energy theory
inorganic nutrient solubilizing theory
Field and greenhouse experiments were conducted to determine the effect of microbial inoculants called Effective Microorganisms (EM) and its interaction with farmyard and green manure on the structure of Collembola community on the nutrient mineralization by Collembola, and yield of carrot (Daucus carota L.). The study was conducted in the Organic Nature Farming Training Center in Wonosobo, Central Java, Indonesia from December 2007 to March 2008. The treatments were farmyard manure (FYM), FYM + EM), green manure (GM), GM + EM, EM alone and the unmanured control. Abundance of Collembola was significantly increased by application of farmyard manure under field condition and by green manure under greenhouse condition. Addition of EM on green manure in the greenhouse condition resulted in the greatest increase in abundance and richness of Collembola. Isotoma sp (Isotomidae) was the most abundant Collembola in each treatment; 68.13% in the field and 62.93% in the greenhouse. The combination of GM and EM had a significant effect in increasing rate of mineralization as inidcated by the reduction in soil C/N ratio, increasing soil P concentration, and increasing yield of carrot. Natural stable isotope analysis using N and C show that Collembola may have a role in enhancing N mineralization as affected by EM.
