Resource Book on Horticulture Nursery Management

2.3 Glossary
Apomixis: Seedlings which are true to its mother plant.
Asexual propagation: Propagation by using vegetative parts of plants such as leaves,
stems, and roots.
Micro-propagation: Technique of vegetative propagation by using tissue culture under
aseptic conditions with artificial media.
Parthinocarpy: Formation of fruits without union of male and female organs.
Polyembryonic varieties: Varieties which give rise to more than one seedling from one
seed.
Seed dormancy: Prevention of a seed from germination even when provided with
favorable environment.
Seed Germination: Emersion of embryo from seed.
Seed scarification: Breaking, scratching, or softening the seed coat for easy germination.
Seed Stratification: Seeds of some temperate zone plants which are treated with chilling
temperature.
Sexual propagation: Union of the pollen (male organs) with the egg (female organs) to
produce a seed.
2.4 Points to Remember
� Both sexual and asexual methods are used in plant propagation. Selection of
particular method for a particular crop is very essential. For production of hybrids in
sexual plant propagation some selective treatments are necessary.
� To maintain the purity in seed produciton, rouging is essential. The structure of the
seed is more complicated than any other vegetative part of the plant.
� The germination process in seed propagation and rooting process in vegetative
propagation are the first steps in plant propagation.
� Tissue culture on commercial basis is important method in plant propagation but
requires special techniques and skilled manpower.
� Seed play a very important role in crop production and varietal developement as it is
the only means of sexual propagation.
2.5 Self Check Questions
1. Define: a. Seed Dormancy, b. Seed Viability, c. Sexual Propagation, d.
Polyembryony, e. Seed Scarification
2. State the importance of asexual method of plant propagation.
3. What are the criteria for selection of good seeds?
4. What is seed treatment? State importance of seed treatment.
<strong>Resource</strong> <strong>Book</strong> on Horticulture Nursery Management : 40