Abstract
A comprehensive study was carried out to find the effect of power (Batteries), swath width, discharge rate and wind speed on
droplet size and density of locally available ULV sprayer with the objective to minimize the application rate, drift and
wastage of pesticides while increasing insects mortality. Conventional tractor mounted boom sprayers apply spray on the
upper side of the leaves. Most of the sucking insect (whitefly, aphid, jassid, thrips, etc.) have there kitchen houses on the
lower side of leaves of the upper half portion of cotton plant which not only get protection from sprays but also enjoy the
shadow of leaves as of umbrella coverage. Therefore, the spray chemicals by conventional sprayer do not hit the actual target
and cause wastage of the spray material to the ground and air. Different pests and insects required different number of
droplets per cm2. The test bench consists of a rectangular frame, 2 rollers, variable speed motor, ULV stand, and canvas belt
with some accessories. Test bench facilitates the mounting of ULV sprayer at different heights. It has a variable speed motor
to rotate the canvas belt is actually to simulate the swath width of spray while speed of belt simulates the traveling speed of a
man, effect of voltage supplies, discharge rate and wind speed on droplet size and density. Droplet distribution was obtained
on water sensitive papers fixed on rotating belt. A variable speed gear motor was used for power supply to the rotating belt. A
bracket fan was used to create required wind speed.
