Journal of Pure and Applied MicrobiologyVol. 9 No. Special Edition Nov. 2015

Optimization of Straw Size, Dose of Compost Inoculant along with Engineering and Microbiological Parameters for Paddy Straw Degradation in Shortest Possible Time

M. Muzamil, Indra Mani, Adarsh Kumar, Livleen Shukla, Satish Lande and Anil kumar Saxena

IARI, New Delhi - 110 012, India.

Received on 08 June 2015 and accepted on 24 September 2015



The aim of the study was to analyze the extent of involvement of labour in manual chopping of paddy straw and also to determine the optimum size of paddy straw for the development of paddy straw collector-cum-chopper to degrade the valuable agro residue in shortest possible time for value added product using microbial inoculants for composting. Three sizes were selected; after harvest, single blade chopping (4-5 cm) and two blades chopping (2-3 cm) of manually operated chaff cutter. Three different doses of compost inoculant prepared from Aspergillus awamori, Trichoderma viride, Phanerochaete chrysosporium and Aspergillus nidulans (T1: untreated; T2: 300 g; T3:500 g; T4: 1000 g) were applied on the paddy straw for conversion to compost. The moisture content was maintained at 60 % of water holding capacity (WHC) by adding water at different intervals. The straw size of 4-5 cm and inoculant dose of 1000 g per tonne of the material surpasses all other treatments in terms of low cost for chopping and power consumption along with improvement of selected parameters pH 7.0 with subsequent increase in electrical conductivity 0.5 dS/m, nitrogen content maximizing 0.78 %, phosphorus 93.7 ppm, potassium 0.69 % with 56.9 % decrease in carbon content from first turning to fourth turning in 35 days. The C: N ratio decreased from 84.89 to 18.70 (a reduction of 77.97 %) from initial value and is a definite parameter for conversion of substrate to compost. The study showed that though some of the parameters for straw size (2-3 cm) were better than that of size (4-5 cm) at 1000 g inoculant dose, overall the latter was found to be the best size for the development of paddy straw collector-cum-chopper as well as preparation of compost in shortest possible time.

Keywords : Straw size, inoculant dose, pH, C: N ratio, Paddy Straw collector-cum-chopper, compost.