Deflecting the bounce

A new retention system that could reduce pesticide use

Pesticide spraying has a retention problem : only  two per cent of the spray sticks to the plants, while a significant portion bounces off the plants into agricultural lands, and the run off eventually pollutes our water sources .Now a team of researchers from the Massachusetts institute of Technology has found a way which could allow farmers to get the same effects by using just 1/10^th of the pesticide .They have developed a combination of two inexpensive additives to the spray -each  prepared with a different polymer  substance. One gives the solution a negative electric charge; the other results in a positive charge. When tow of the oppositely -charged droplets meet on a leaf surface, the form a hydrophilic (water attracting) ‘’ defect” that sticks to the surface and increases the retention. The researchers hope to conduct field trials of the new system in small farms in India.

Down To Earth 16-30 September 2016