Seed multiplication of improved open-pollinated varieties
Practical Action
To restore food security amoung smallholder farmers, stakeholders have been calling for the
implementation of sustainable agricultural practices. Open-Pollinated Varieties (OPVs) are an option
for achieving sustainability. Most OPVs are said to perfom well under low external input. To date,
several organisations have been participating in promoting and advocating for the production and
uti I isation of OPVs amoung small holder farmers.
Crop production in Matebeleland South Province is mostly rain-fed. But, the province receives less
than 600mm of rainfall per annum, which usually results in successive droughts and crop failures.
The few seed stocks and gra i n reserves are wi ped out before the onset of the next farm i ng
season. Community-based seed multiplication of OPVs can mitigate against hybrid seed
unavailability and its soaring cost thereby increasing access to standard seed for communal areas,
especially in drought prone areas.
Types of seeds
Standard grade seed: is seed that has not been produced under the certification scheme but
meeting purity and germination test standards e.g. Retained seed.
Certified Seed: is grown under the seed certification scheme e.g. hybrid
Activities in open pollinated varieties (OPVs) seed multiplication
Field crop inspections
Done at least four times
• Before planting
• When crop is still young and growing in the field
• When crop is flowering, and;
• When crop is producing seed
Before planting: To check on crops grown in the previous year.
When the crop is growing: To check on isolation distances, weeds and removal of off types.
At flowering: To check for weeds, diseases and how crop is being managed.
Before harvesting: To make sure that all off types have been removed.
Requirements for seed multiplication
Land requirements; A seed crop should not be grown on a field that was grown on the previous
year so as to:
• Reduce pests and diseases
• Reduce weed pressure
• Improve soi I structure
• Ensure that seeds of previous crop wiII not germinate and mix with your variety and;
• Use of residual nutrients
Isolation
This is the distance that should be left between similar seed crops to prevent cross pollination.
The OPV seed production fields may be isolated in space or time, or both. The isolation distance
for OPV seed production is normally 250 - 350 m.
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