DEVELOPMENT OF A TECHNOLOGY TO PRODUCE ENRICHED COMPOST FOR USING AS MANURE TO MINIMIZE SOIL ORGANIC MATTER REDUCTION AND CHEMICAL . FERTILIZER APPLICATION

Abstract

Two experiments were conducted of which one was carried out at world tech Agro Complex campus of Dinajpur to select a better enriched compost making technology during July to September 2005; and another one was a field trial carried out at BARI sub station, Thakurgaon to test the effect of the produced compost on the yield of Brinjal during October 2007 to April 2008. For the first experiment, eight organic sources at three different combinations were allowed to decompose in presence of effective microorganisms (EM) of INFRC in box method under semi aerobic condition for making enriched compost. Organic substrates were Poultry litter, cow dung, oil cake, bone dust, saw dust, ash, shell dust, and water hyacinth. Decomposition continued in three boxes separately for 40, 50 and 60 days. Compost of 50 days decomposition (Type II) containing * 20.22% OM, 1.47% N, 4.79% P20s, 1.35 K20, 0.18% S, 2.86% Ca, 0.77% Mg and 148 ppm Zn was found better considering good C:N ratio and nutrients, which was selected for the field trial on brinjal (BARI 6). The compost was dark grey in colour, odorless and micro granular in size. This was named Organic Power (OP). The second experiment was set up in a randomized complete block design with three replications, There were six treatments: control treatment (T; = OP» + Mf, RCD), BARC recommendation (T2= CD01 + 1b RCD), obtained enriched compost i.e. OP treatments (T3 = OPos: + 4, RCD, Ty = OPio:+ 1/2 RCD, Ts= OPis:+ 1/2 RCD and Ts= OP20:+ '/2 RCD). All chemical fertilizers, cow dung, compost, and '2 of urea were applied at final land preparation. Rest Y% of urea was top dressed at every 30 days interval to each plot up to 120 DAT. All the . parameters significantly responded to the fertilizer treatments over the control. Plant height, average weight of fruit/plot, average number of fruit/plot increased due to different treatments. The highest number of fruits (140/plot) was observed in T, treatment and the highest weight (452.66 gm) of fruits was recorded in T; treatment. Economic analysis revealed that the highest marginal rate of return was 1270.40% with gross margin of 538160 Tk./ha/yr due to T, (OP; 0 +), RCD) treatment. Organic matter status of soils increased slightly due to addition of organic power and cow dung as the organic sources along with the chemical fertilizers. Therefore, it may be inferred that Ty treatment would be better for the binjal cultivation. Overall observations is that the use of organic source like Organic Power or any other organic manure should be the practice for maintaining .. soil fertility and reducing the use of chemical fertilizer.