In:
Canadian Journal of Botany, Canadian Science Publishing, Vol. 48, No. 1 ( 1970-01-01), p. 95-109
Kurzfassung:
Apical, middle, and basal 5-mm segments from decapitated Phycomyces blakesleeanus sporangiophores cultured on plain agar blocks regenerated sporangiophores after wound closure. Hyphae formed very rarely. Maximum regeneration frequency decreased between apex and base from 100% to close to 70% in stages 1 and 3, and from 80% to 23% in stage 4. The regeneration speed declined along the axis. The frequency of two or more initials per segment decreased basipetally in stages 1 and 3, but not in stage 4. Most segments formed sporangiophores at the apical end but regeneration from the basal end alone increased towards the base in stages 1 and 3, and was found on up to 30% of the stage 4 segments without gradient along the axis. A few segments regenerated at both ends at all positions. Initials emerged laterally at the apical end of most top segments and from the wound closure wall on almost all others. The diameter of single sporangiophores on apical segments was larger and their maximum stage 1 length shorter than on the rest. Both were less on stage 4 than on 1 and 3. The final length on either stage 1 or 4 was the same at all positions but the former was more than twice as great as the latter. One-millimeter stage 1 segments regenerated very thin sporangiophores but polarity was much weaker than in 5-mm pieces.Almost 90% of stage 1 segments with whole apices and open basal ends continued growth without branching. Most of those which stopped regenerated near the tip. Stage 3 and 4 segments tied off basally continued growth without regenerating above the tie, but if the end was open the sporangia stuck to the agar because of turgor loss, elongation stopped, and regeneration occurred close to the sporangia at slower speed than on decapitated apical segments.Cytoplasmic extrusion and formation of exudation drops were studied, wound closure was followed on middle stage 1 segments, and preliminary observations were made on movement of cell contents during regeneration.
Materialart:
Online-Ressource
ISSN:
0008-4026
Sprache:
Englisch
Verlag:
Canadian Science Publishing
Publikationsdatum:
1970
ZDB Id:
218116-2
ZDB Id:
1481926-0
SSG:
12
