Fall armyworms which have become a menace to maize growing in Uganda could be a case of the past after Ndejje University developing a bio-pesticide to kill them.
Armyworms (Spodopterasp), which had first been reported in Kayunga, Kasese and Bukedea Districts in July 2016, have reportedly now spread to over 20 Districts in Uganda.
The Uganda Ministry of Agriculture was quoted early this year as having estimated that the country could lose 450,000 tonnes of maize to the pest which is equivalent to $192m (shs692b). It however promised to procure emergency pesticides, including Profenofos 40% and Cypermethrin 4% to fight the worms.
To answer the country’s outcry, the Department of Agriculture in Ndejje University has come up with a bio-pesticide made from indigenous micro-organisms, which it is currently testing against the pest and has recorded some success so far.
Olivia Makumbi, the Departmental Head said there was an urgent need to come up with an environmentally friendly, non-toxic but effective pesticide to fight this pest.
“All these government emergency pesticides including profenofos and cypermethrin are expensive, alter soil pH and are also toxic to living things. They get into the food web and are eventually consumed by human beings. Moreover, these chemicals are not host specific and end up killing even beneficial organisms like bees,” the don warned.
She said that the university has made a thorough study and explored the potential of the bio-pesticide to control the Fall armyworm which is currently rendering intense damage to maize gardens in the country.
The initial study and test of the pesticide was however successfully done on maize planted in Mr. Zephania’s farm opposite Ndejje High school in Ssambwe Parish, Nyimbwa sub-county in Luweero District.
The university has made bio-pesticides from beneficial indigenous micro-organisms captured from the air and the raw ingredients from rice wash water and milk.
In the case of pest control, these micro-organisms acting as bio-pesticides can control crop pests by interfering with pest feeding mechanisms leading to their death.
Before spraying, observations made on the maize planted on Mr. Zephania’s farm indicated that both the Fall army worm (Spodopterasp) and the maize stalk borer (Busseolafusca) were present in the maize plant, according to the university’s preliminary results.
Part of the field had been sprayed with an inorganic insecticide (Cyperlacer) containing Cypermethrin as the active chemical. The University’s research team measured off a plot of approximately 30 by 20 feet from the unsprayed part and this was sprayed once a week (for 3 consecutive weeks) with the organic bio-pesticide at a rate of 100 mls in 20 liters of water. During spraying, the nozzle of the pump was directed into the funnel of the youngest leaf where the worms hide and feed.
Observations done on the sprayed maize some 4 days later indicated fewer plants still being infested with live worms. A number of dead worms were noticed in the maize. One week after the first spray, Previouslyattacked maize was observed to be resuming growth.
Subsequent observations carried out on the same maize plot a week after the third bio-pesticide application indicated that the maize where the bio-pesticide was applied had very few infestations and maybe this was due to omission during application brought about by the fact that the maize not planted in rows and therefore omitting a planted one was very possible. In addition, the maize in this plot was growing more vigorously, was taller and greener than that which had been sprayed with cyperlacer. This might have been due to the fact that the bio-pesticide is also a foliar feed.
Basing on these preliminary findings, Ndejje University is now set to carry out more tests with the bio-pesticide on other farmers’ maize plots and in the laboratory so as to come out with more scientific based information about the efficacy of the bio-pesticide to control the Fall armyworm.