Notes to broadcasters
Note: There are three different types of maize stemborers. The maize stemborer (Busseola fusca) and the pink stemborer (Sesamia calamites, Ostrinia furnacalis) are found in Africa. The spotted stemborer (Chilo partellus) is found in East Africa and the Indian subcontinent.
Is the maize stemborer a problem pest for you? If so, don’t despair. You can rescue your crop and reduce pest damage if you take the time to observe your crops and the stemborers carefully.
Start by watching the activity of the stemborers. You will see that they start by chewing holes in the leaves of corn, rice, and other grain crops. Then they chew into stems and stalks, cutting off the flow of nutrients and water to the rest of the plant. The worst part is that you might not know they are there until the damage is done.
Look for holes in the leaves to find out where the stemborers are. When you know where they are, it’s much easier to control them. For example, in the Philippines, farmers noticed that maize stemborers often begin by eating the tassels (male flowers) of the corn. So, after pollination, they pull out the tassels and burn or bury them to kill the stemborers.
The best time to control stemborers is while they are still chewing the leaves. If you don’t control them then, before they enter the plant stems, the stems break in the wind and the plants wither and die.
Here are some ways to manage stemborers:
You can also try growing maize and sweet potatoes together. Tiny, friendly wasps called Trichogramma wasps are attracted to sweet potatoes. These wasps kill stemborers by laying eggs in the stemborers’ eggs. So it’s good to have them around.
Neem seed spray is one of the homemade pesticides you can use to control stemborers before they enter the stems. Collect seeds from ripe neem fruit. Dry and clean the seeds well. You will need one big double handful of seeds for every litre of spray you prepare. A double handful is the amount of neem seeds you can scoop up with two hands. If you want to prepare 10 litres of spray, crush or grind 10 double handfuls of seed into a coarse powder. Mix this powder with 10 litres of water. Stir the mixture well. Leave it covered overnight. The next day, filter the mixture through a fine cloth. Apply the spray with a sprayer, a watering can, or a small broom.
If you grow rice, you can use neem in a different way. Just take neem seeds, crush them roughly and mix them into the soil of your field. When it rains or you irrigate, the neem will mix with the water and go into the plant where it helps the plant protect itself against stemborers and other pests.
This script was researched by Boyd Fuller, Agriculturalist, Toronto, Canada. It was reviewed by Dr. Hélène Chiasson, Entomologist, Montreal Canada.
The publication of this script was made possible with the generous support of The George Cedric Metcalf Charitable Foundation, Toronto, Canada.
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