The push-pull approach to protecting maize from stem borers is a good example of how farmers can change the field environment to put pests at a disadvantage. This type of alternative pest management often produces benefits beyond protecting the crop. In this case, napier grass and desmodium provide good fodder for livestock. Desmodium also improves the soil, improving water retention and adding nitrogen.
Infonet-biovision, a web-based tool which offers information to trainers, extension workers, and farmers, provides greater detail on the push-pull approach in the 12 steps listed below. If stem borers and striga (sometimes called witch weed) are major problems in your area, you may wish to produce a program on the topic, sharing this week’s news story and supplying the information below. A live discussion featuring one or more farmers or extension workers familiar with the push-pull method would be a good addition.
How to plant a push-pull field:
1. Plant napier grass (Bana variety is the best) in a border around the maize plot.
2. Plant at least three rows of napier all around the maize field. Apply two handfuls of well-decomposed farmyard manure in each hole.
3. In the first year, plant napier grass before the rains so that it has a head start on the maize. The stem borer moths will like the larger napier grass more than the maize.
4. Get desmodium seeds from seed companies or your neighbour who has started growing it. For one acre of land, one kilogram of desmodium seed is needed.
5. Alternatively, you may plant desmodium vines. In this case, plant the vines when there is enough rainfall and soil is moist.
6. Prepare the soil carefully so that it is as fine and clean as possible.
7. Using a strong, pointed stick, make a furrow in the middle of the rows where the maize will be planted.
8. Mix the silverleaf desmodium seed with fine sand or fine soil (about one handful of seed and two handfuls of sand).
9. Plant desmodium with the rains for maximum germination.
10. Plant your maize in the field surrounded by napier grass.
11. After three and six weeks, trim the desmodium so that it does not overgrow the maize plants.
12. Keep the field weed-free so that the napier has a head start on the maize. The moths will like the larger napier more than the maize.
For more information from infonet-biovision on the push-pull approach, visit: http://www.infonet-biovision.org/default/ct/253/soilFertilityManagement .
You may also wish to produce a show that invites farmers to call-in or text-in about their experiences with alternative pest control methods:
-Have farmers in your area heard of or tried intercropping as a way to control weeds or unwanted insects?
-Have farmers in your area discovered other alternatives to commercial pesticides?
-Do they find the alternatives more or less effective in reducing pest damage and increasing yields?
To browse Farm Radio International scripts on pest management, go to: http://farmradio.org/english/radio-scripts/pest.asp .