Claim · model-written summary
Cambial reactivation is preceded by a decrease in density of cambial cell protoplasts and cell wall thickening, but not by cell enlargement.
- Taxon
- Robinia Pseudoacacia
Robinia pseudoacaciat0 - Organ / stage
- cambial cell protoplastse1
- Outcome
- density of cambial cell protoplastse1
- Direction
- decreasee1
Verbatim
t0“Robinia Pseudoacacia”
e1“Cambial reactivation (division) is preceded by a decrease in density of cambial cell protoplasts and cell wall thickening but not by cell enlargement”
Title
The Cambium and Seasonal Development of the Phloem in Robinia Pseudoacacia
William F. Derr; Ray F. Evert American Journal of Botany 1967. doi:10.2307/2440792
Other claims from this paper (12)
- Observation The black locust cambium consists of several layers of cells at all times.
- Observation During resumption of cambial activity, periclinal divisions occur throughout the cambial zone.
- Observation Early divisions during cambial resumption contribute largely to the phloem side.
- Association The period of greatest cambial activity coincides with early wood formation.
- Observation Phloem differentiation begins in early April and ends in late September.
- Observation The amount of phloem produced per year is quite variable, ranging from 1 to 10 bands of sieve elements.
- Observation Cessation of sieve element function begins with accumulation of definitive callose in the first-formed sieve elements.
- Observation By late November all but the last-formed sieve elements are collapsed.
- Observation All sieve elements are collapsed by mid-winter, before new phloem production resumes in spring.
- Association Phloem differentiation precedes xylem differentiation by at least 1 week.
- Association Functional sieve elements are present about 3 weeks before new functional vessel elements.
- Observation Xylem and phloem production ends simultaneously in most trees.