Dr. S. JOSEPH REDDYNKR GURUDATT MADDU2017-10-162017-10-162015http://krishikosh.egranth.ac.in/handle/1/5810033174D5217On one side of the coin negative impacts coupled with escalating prices of mineral fertilizers and on other side high demands of nutrients to soil due to intense cultivars of high yielding varieties, the use of organic matter is necessary to meet the nutrient demands with low cost. In India application of farmyard manure (FYM) to the agricultural fields has been generally accepted practice, which improves soil physical, chemical and biological properties of soil. Keeping in view the problems of not meeting the desired agronomic rates and disintegration of large manure un-decomposed clods during manual application of FYM to the field, a machine (FYM pulverizer cum spreader) was developed by RARS, Nandyal to pulverize and spread the manure simultaneously to the fields. Pulverization of large un-decomposed FYM clods to 0 to 40 mm size encourages the faster decomposition when hits the lands due to the more surface area exposed for the attack of microorganisms present in the soil, environment and FYM. To meet the desired FYM application rates to the fields in required pulverized form, it is necessary to study the physical properties of manure affecting the performance of the machine and behavior of the machine at different component settings and operated under prescribed levels. Hence, a study was carried out on the performance evaluation of the FYM pulverizer cum spreader. The machine parameters with levels viz., feed control shutter opening (half open and full open), number of blades per flange of rotor (2, 3, and 6) and operational parameters viz., spreader peripheral velocity (4.72 ms-1, 6.92 ms-1and 7.86 ms-1) spreader forward speed of (2 Km h-1,3 Km h-1 and 5 Km h-1) were selected to study the effect on bulk density, clod size distribution and FYM application rate. Based on the study, the machine and operational parameters were optimized for minimum bulk density, higher percentage of 0 to 40 mm clod distribution and desired range of agronomic application rates. The experiments were carried out at stationary condition as well as in field conditions. The experiments revealed that, the decrease in bulk density and increase in percentage of 0 to 40 mm clod size distribution was observed when the rotor peripheral velocity was increased from 4.72 ms-1 to 7.86 ms-1 and numbers of blades were increased from 2 to 6. The lowest bulk densities of 0.510 g cm-3and 0.515 g cm-3and higher 0 to 40 mm clod size percentages of 78.28 and 66.55 was recorded at peripheral velocity of 7.86 ms-1 and 3 number of blades for both half and full shutter opening of the machine respectively. The application rate was increased when rotor peripheral velocity increased and decreased with increase in forward speed. The agronomic application rates of 5.8 t ha-1and 12.6 t ha-1with minimum bulk density and higher percentage of 0 to 40 mm clod size distribution was observed at forward speed of 3 Km h-1, peripheral velocity of 7.86 ms-1 and 3 blades per flange of rotor at half shutter and full shutter opening. A prototype FYM pulverizer cum spreader was developed and evaluated under field condition with the best optimized variables derived from the experimental trails. The bulk density, clod size distribution and application rate was observed as 0.512 g cm-3 & 0.521 g cm-3, 75.99 % & 64.45 % and 5.9 t ha-1 & 12.5 t ha-1 at half and full shutter opening area respectively. The cost of operation of FYM pulverizer cum spreader works out to be Rs.620 per acre when the machine is used for dry FYM pulverizing cum spreading operation. There was a saving of Rs.504 per acre over traditional method of spreading.en-USnullThesis