POC Conf. Call 5-10-11

POC meeting, Webex Conference Call; Date: Tuesday May 10th, 2011 10am (PDT)

In attendance:

POC members:

Absent:

Collaborators:

Acceptance of the minutes from the POC_Conf._Call_5-06-11?

gametophytic phase and sporophytic phase

sporophytic phase (PO:0028002)

Current definition: A plant life cycle phase that is the product of fertilization. [source: POC:rw]

Comment: During the sporophtyic phase, a plant may produce meiospores by meiosis.

Proposed definition: A plant life cycle phase (or a whole plant growth stage) that begins with fertilization or the division of a non-fertilized embryogenic cell.

Comment: During the sporophtyic phase, a plant may produce meiospores by meiosis. A whole plant in the sporophytic phase usually has twice the chromosome complement of a plant in the gametophytic phase, but may not in the case of apogamy or in vitro culture of haploid embryos.

gametophytic phase (PO:0028003)

Current definition: A plant life cycle phase that arises through meiosis. [source: POC:rw]

Comment: During the gametophytic phase, a plant may produce gametes by mitosis.

Proposed definition: A plant life cycle phase (or a whole plant growth stage) that begins with meiosis.

Comment: During the gametophytic phase, a plant may produce gametes by mitosis. In bryophytes and pteridophytes, a gametophytic phase may begin without meiosis by apospory. This usually occurs when damage to a plant in the sporophytic phase leads directly to the growth of a plant that is in the gametophytic phase but bears the chromosome complement that would normally be found in the sporophytic phase. A whole plant in the gametophytic phase usually has half the chromosome complement of a plant in the sporophytic phase, but not in the case of apospory.