Question
- How is artificial hybridisation considered a crop improvement programme?
- Explain the process of artificial hybridisation, if
- Female parent bears bisexual flowers.
- Female parent bears unisexual flowers.
✓
Answer
- Artificial hybridisation involves crossing of different varieties or species or even different genera to combine the desirable characters of the two parents to produce a commercially superior variety.
- When the female parent bears bisexual flowers:
- Emasculation is necessary; it is the removal of anthers/ stamens before the pollen grains mature.
- The emasculated flower is bagged to prevent contamination of the stigma with unwanted pollen grains.
- When the stigma attains receptivity, the pollen grains collected from the selected male parent are dusted on the stigma.
- The flower is rebagged and allowed for further development.
- When the female parent bears unisexual flowers:
- There is no need for emasculation.
- The female flower is bagged before the stigma becomes receptive.
- When the stigma becomes receptive, the pollen grains collected from the selected male parent are dusted on the stigma.
- The flower is rebagged and allowed for further development.
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