Sympodial branching

Curvularia colonies are rapid growing, woolly, and gray to grayish black or brown. The conidiophores are dematiaceous, solitary or in groups, simple or branched, septate, and typically geniculate. The conidia are two to several celled, usually curved, dark with pale ends, solitary, and typically with a dark hilum. The conidia develop from a sympodial conidiophore. Works by Ellis should be consulted if a Curvularia isolate must be identified to species. 

Sympodial branching the terminal bud at some stage in the life... 

N.B, In a sympodial structure the axes may have a monopodial brancning for some time up to several years, but eventually the terminal bud will flower and die. Such a mixture of main monopodial and ultimate sympodial branching in an inflorescence is the thyrse (see 45.3.1). To decide what type is involved, the relative position of axes, leaves or bracts, and inflorescence or flowers (check for scarsl) must be observed very carefully for instance the presence of a leaf on a branch opposite to the inflorescence clearly indicates the sympodial type the apparently lateral inflorescence is in fact the terminal bud, while the apparent straight continuation of the stem is in fact the outgrowth of the axillary bud of the leaf. 

Ptychomnion cygnisetum is a nanandrous species hence character state coding of characters 1-25 refers to female plants only. Ramification type of P. cygnisetum could not be determined with certainty. Ramification seems to be monopodial, but in the material examined the older parts of the (female) plants are usually damaged or not collected. Occasionally, ramification shows some resemblance with sympodial branching. Hattaway s (1984) description of ramification is, unfortunately, inconclusive. Hence, the state of character 1 is coded as unknown for this species. 

Special cases of sympodial branches are those that form stolons, i.e., specialized shoots with small and often quite distant leaves. At a certain stage stolons either gradually transform into normal... 

Subterminal branches are sympodial branches that develop just below a terminal gynoecium or androecium. Subterminal branching is especially common in acrocarpous mosses, and in many groups most of the shoots are just a series of subterminal branches (e.g., Pottiaceae, Grimmiaceae). Subterminal branches, or secondary axes from the basal part of perichaetia in cladocarpous mosses, are present in many members of the Hypnales (La Farge-England, 1996), but their role in the plant architecture is almost never comparable with that of ordinary branches. 

Sympodial growth prodnces an axis called a sympodium, comprising a series of connected shoot units, each derived from a different apical meristem. The shoot units that make up the sympodium are called sympodial units, or modules, and each sympodial unit provides further shoot extension growth from a lateral meristem. The sympodium may or may not have determinate lateral branches, and the sympodial units themselves may be determinate or indeterminate. 

Reiteration can be monopodial or sympodial. Both types reproduce the developmental sequence from juvenile to mature. Monopodial reiteration involves the dedifferentiation of the apical mer-istem, which reverts to the production of juvenile tissne (e.g., repeating the heteroblastic series of axis development). The resnlt in this case is a continnous axis with the heteroblastic series repeated in tandem. In contrast, sympodial reiteration develops from dormant lateral buds to reproduce the architectural unit as a lateral branch. 

La Farge-England (1996) provided a detailed overview of growth form, branching pattern and perichaetial position in mosses. She also provided definitions of sympodial and monopodial branching patterns, indicating that these processes occurred at different hierarchical levels. 

By producing determinate or indeterminate branches at the level of primary module sympodial branching is reiterative. It is full reiteration rather than partial reiteration. The new primary module produced in this way has the potential to produce all the subsidiary branches and structures of lower hierarchical levels characteristic of the species (i.e., the components of the architectural unit). Sympodial branching then produces new architectural units. Less commonly sympodial branching may also produce shoots at other hierarchical levels, but the most important level for moss structure is that of the primary module. 

Sympodial branching produces determinate or indeterminate lateral branches of the same hierarchical order, producing a series of connected modules of the same hierarchical order. 

Sympodial reiteration produces a series of connected primary modules due to the activity of a series of different terminal apical cells. It is the combination of complementary activities of sympodial growth and sympodial branching. 

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