Mwea farmers separate pest infested rice with urea

Rice farmers in Mwea Irrigation area are mixing urea, salt and water to separate healthy ripe seeds from the raw and pest infested ones for planting, a move that has seen them save time and money at a time when poor planting seeds have taken a toll on overall rice yields. Having long planted poor seeds from the previous harvest, which are hard to detect by naked eye, the farmers' yields have been plummeted with the collective yields dipping upto 25 percent in 2010 which was attributed to poor planting seeds.

Now with the help of one of them who has interacted with Bangladesh rice farmers where the method has been perfected, the farmers have learnt a cheaper way of sourcing for planting seeds. Traditionally upon realizing that poor seeds were responsible for the low yields farmers carried samples to agricultural laboratories in the area to have them analysed which would cost them upto Sh500 in analysis. Now the tried and tested simple method of Urea and water is working wonders and saving the farmers a fortune. “I have used it twice and I have increased my harvest by upto three bags. It now makes sense how important a healthy planting seed is,”Dorothy Wangura a rice farmer says.

“After winnowing partially filled grains and grains with holes are still mixed with the full, healthy grains. This is where the process of separation starts,”said Meshack Mwati the farmer championing the simple separation method now commonly referred to as seed floatation. Farmers pour clean water into a container depending on the size of the seeds to be separated. They then add salt or urea to that water to change the specific density of the water.

“One should keep on adding salt, or urea, or even clay, until a freshly laid egg can float on the surface of the water. It was Bangladeshi women who made the discovery that when an egg could float to the surface of the water, the density of the water was just right for the seed floatation method,”Mwati further said. Next, farmers drain the grains to the water and mix everything by hand. After a while all the damaged and light grains starts to float to the surface of the water while the healthy grains settle at the bottom of the container. Farmers then remove the damaged and partially filled grains that are now floating on the surface of the water. The healthy grains settled at the bottom of the water are then cleaned twice, or three times in clean water and are ready for planting.

“However there are those that have black or brown spots on them and even if they are bad they dont float with with the rest. For this manual sorting is encouraged,”said Mwati. The simple innovation, though cumbersome according to certain agricultural officers, has been instrumental in determining the difference between a good and a bad harvest season in Mwea with the farmers now trialling it with other cereals.