Agriculture Reference
In-Depth Information
Table 3. Plant traits conducive to invasibility, colonization and weediness during the plant life histo-
ry processes of birth, dispersal, recruitment, vegetative growth and seed reproductive growth
Life history
Traits
process:
Birth
Genetic:
• variability of progeny by genomic rearrangement
• local adaptation:
a] by genotypic and phenotypic variability (biotypes)
b] by epigenetic/epistatic mechanisms (e.g., chromosomal methylation)
• small genome size [7]
Fertilization:
• attractants for pollinating species: chemical, morphological
• plastic stigma receptivity timing
Seed development:
• rapid seed maturity
• rapid development of germination competence of immature, prematurely
harvested, seeds
• seed or bud primary dormancy induction:
a] heterogeneous among seeds of a cohort
b] inherent and dynamic in response to post-abscission experience
(seed memory)
• optimized seed size (and seed components) for habitats exploited
• high seed quality regardless of seed productivity
• Constitutively expressed polymorphic seed production (e.g., sunflower
seed dimorphism)
Environmental:
•
fertilization and flower/zygote development stress tolerance
Dispersal
Spatial:
• seed shattering
• dispersal structures:
a] for habitat placement by exploitation of wind, water, and animal
vectors
b] multiple dispersal modes
c] lack of dispersal structures (gravity) for ensuring local placement
• perennial bud dispersal:
a] independent buds: ramet
b] parental buds: ortet
• attractants for dispersal vectors (e.g., animals): chemical, morphological
Temporal:
•
formation of soil seed and bud pools (dispersal in time)
•
seasonal seed and bud dormancy cycling: after-ripening and secondary
dormancy induction
•
soil predator and disease tolerance (e.g., endophytic fungi colonization of
seed for disease tolerance)
Recruitment
Seed:
•
heterogeneous emergence timing from differential dormancy levels among
seed of a cohort (including non-dormancy)
•
germination over wide range of soil and resource conditions
(Continued on next page)
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