Arun KumarDash, Bhabani Shankar2018-07-092018-07-092016-01http://krishikosh.egranth.ac.in/handle/1/5810058529Plant protection is an essential operation in the basic practices of crop production. Data shows that diseases, insects and weed put together cause 31 to 41 % damage to the crops produced worldwide. In India, annual crop loss is estimated to be around 50,000 crores due to pests. Various plant protection measures are followed throughout India, among which chemical method is most widely used. Common plant protection equipments include Knapsack sprayers (manual and power operated), foot sprayer, tractor mounted sprayer in India. Most of the sprayers spray chemical from the top of the plant which causes improper spray distribution in case of crops with dense or medium canopy. The pest and insets present inside the canopy and under the leaves are not affected by this spray which leads to infestation and damage even after spraying. Keeping in view the above problems the development of sprayer to perform intra canopy and under leaf spraying was undertaken. A selfpropelled intra canopy boom sprayer was developed for spraying chemical in small height row crops in Indian condition. It was suitable for small land holdings and had low cost of operation. The self-propelled intra canopy boom sprayer had an improved boom section with even flat fan nozzles mounted on the top of the boom to spray chemical from the top of the row and hollow cone nozzles placed at one third of plant height from the ground in between the rows to spray liquid into the canopy. Two hollow cone nozzles mounted in a swivel body were placed in between rows with the help of hose drops, helped in spraying chemical in either directions. For every row of plants three nozzles (one flat fan and two hollow cone) were used to spray the liquid to get maximum leaf area coverage. The performance of the developed sprayer was evaluated both in laboratory and field condition to ensure that the objectives are fulfilled. The nozzles were tested in the laboratory to find its volumetric distribution, swath and spray angle at different pressure and height combinations. The independent parameters for patternator test were operating pressure (1.5, 2, 2.5, 3 and 3.5 kg/cm2), nozzle heights (200, 300, 400, 500, 545 and 600 mm). The flat fan nozzle gave its best volumetric distribution at 2.5 kg/cm2 and 300 mm nozzle height while the hollow cone nozzles at 3 kg/cm2 and 300 mm nozzle height. The swath and angle of spray of the nozzles were determined and it was found that with increase in pressure and height the swath was increased while the spray angle increased with pressure. The droplet sizes produced by both the nozzles were measured using Spraytec laser diffraction technique and the NMD and VMD of the droplets were measured. The independent parameters of the droplet size determination test were operating pressure (1.5, 2, 2.5, 3 and 3.5 kg/cm2) and nozzle height (450 mm). The NMDs and VMDs of the hollow cone nozzle varied between 34 to 23 µ and 200 to 114 µ, respectively while for flat fan nozzle it was 108 to 23 and 199 to 129 µ, respectively with increase in pressure from 1.5 to 3.5 kg/cm2. The uniformity coefficients of the data for both the nozzles were calculated. The flat fan nozzles produced most uniform droplets at 1.5 kg/cm2 and hollow cone at 3 kg/cm2. Both the nozzles produced droplets in the range of very fine to medium for the pressures studied. The machine was tested in the field on September 22, 2015, on soyabean crop at three different speeds (1.5, 2 and 2.5 km/h) and leaf area coverage, NMD and droplet densities for upper and bottom parts of the canopy were measured. The field performance evaluation of the developed sprayer showed that, the mean leaf area coverages were 30.3 and 18.9 % and mean droplet densities were 243 and 263 for upper and bottom part of the leaves, respectively at 1.5 km/h. For 2 km/h sprayer speed the coverages obtained were 22.16 and 10.67 % and droplet densities were 277 and 235 for upper and bottom parts of the leaves respectively. For 2.5 km/h sprayer speed, the leaf area coverages were 15.37 and 4.12% and droplet densities were 259 and 78 droplets for upper and bottom parts of the leaves respectively. It was found that with increase in forward speed of the sprayer the percentage coverage decreased significantly while droplets density declined significantly only for underside of the leaves.ennullThesis