Propagation and Nursery Management
What the domain covers
This domain covers how plants are raised from seed or vegetative parts and how a nursery produces uniform, healthy planting material. The exam tests propagation methods, nursery operations, hardening, and rootstock–scion relationships.
Core rules and concepts
- Sexual propagation uses seeds and creates variation; asexual propagation uses cuttings, layering, grafting, budding, division, and tissue culture and preserves a cultivar.
- Seed lot quality depends on viability, purity, germination percentage, and freedom from pests.
- Cuttings must have correct polarity, nodes, and suitable leaf area; humidity and shade reduce transpiration.
- Grafting joins a scion to a rootstock; cambial contact and alignment are essential, and compatibility limits success.
- Nursery beds need sterilized or clean media, drainage, shade, and timely watering; seedlings are hardened before field planting.
- Hardening gradually reduces water and shade and exposes plants to sun so they survive transplanting.
Worked example
A grower wants true-to-type Alphonso mango fruit. Seed propagation would give variable seedlings, so the reasoned choice is veneer grafting or budding a known scion onto a compatible rootstock. The rootstock supplies vigour and soil adaptation; the scion supplies fruit characters. The graft union must be kept above soil and the joint sealed until union.
Traps
- Expecting seed-grown fruit trees to match the mother tree.
- Planting a grafted tree with the union buried, which encourages scion rooting and disease.
- Skipping hardening, then blaming field conditions for seedling death.