Hand-out 10 - Notes on control of spread of the GGB trough timely harvesting of maize and post-harvest farm hygiene

1. All farmers should practice timely harvesting of maize. Timely harvesting has the following advantages:

a) Saves losses due to:

i) rodents
ii) theft
iii) bad weather
iv) fungi (moulds)
v) storage insect pests, e.g. the GGB, maize weevil, etc.
vi) wild animals

b) Timely harvesting of maize also enables:

i) easier, better, timelier preparation of land for the next crop;
ii) farmers to get another crop (new maize or beans) in some areas;
iii) the fresh stalks to be fed to livestock.

2. The signs for physiologically mature maize are:

1) the stalk system turns yellow or brown;
2) cobs begin to droop on the stalk (in most hybrids)
3) maize is no longer good for roasting
4) nine out of every ten kernels shows a black layer.

3. The following good and hygienic harvesting practices should be heeded by all farmers:

i) The cobs should be harvested and transported carefully to avoid mechanical damage. Mechanical damage lowers the grade of the maize and makes it susceptible to attack by storage insect pests, e.g. the GGB.

ii) The stalks should be cut down immediately and burnt or fed to livestock.

iii) The cobs should be dehusked and the husks should be either burnt or fed to livestock.

NB:

Points ii) and iii) above are very much recommended because they ensure elimination of possible hiding and breeding places for the GGB and other post-harvest insect pests.