POC Conf. Call 5-10-11

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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_4-26-11?

Issues arising from previous meetings:

Conductive cells and tissues for vascular and non-vascular plants

THIS PART IS STILL UNDER CONSTRUCTION

conductive and related cell types for bryophytes and vascular plants

Current parent: axial cell

axial cell (PO:0000081): A vascular cell derived from the fusiform cambial initial and oriented with its longest diameter parallel with the main axis of stem or root. [source: ISBN:0471245208]

Comment: These cells make up the axial system, also known as vertical or longitudinal system.

Existing descendents of axial cell:

sieve tube member (PO:0000289, alt: PO:0000286)

phloem fiber (PO:0004519)

xylem element (PO:0000273)

>tracheary element (PO:0000273)

>>tracheid (PO:0000301)

>>vessel member (PO:0002003)

>xylem fiber (PO:0000274)

>>fiber tracheid (PO:0000355)

>>libriform fiber (PO:0004520)

>>septate fiber (PO:0004521)


The term axial cell, and the current definition, describe a particular type of vascular cells found in wood. This is not appropriate as the parent for xylem and phloem cells. Also, the term axial cell is not widely used. "Axial system" is widely used to describe the vascular tissue in wood (in contrast to the radial system).

Suggest that we obsolete this term, possibly replace with new terms for axial system and radial system


At the bryophyte term meeting on 4-25-2011 (RW and MAG present), we decided that axial cell was not the correct term to use to describe all of the elongated cells associated with conducting tissue in plants. They are different cell types and have different origins, so they should not all be grouped together.


New proposed hierarchy (children of plant cell):

plant cell

>hydroid

>leptoid

>vascular cell (new term)

>>sieve tube member

>>tracheary element

>>>tracheid

>>>vessel member

>fiber cell (new term)

>>phloem fiber cell

>>xylem fiber cell

>>other kinds of fiber cells

>ground tissue cell

>>stereid

>>collenchyma


Proposed definitions:

fiber cell:

vascular cell:

conductive tissue for bryophytes and vascular plants

vascular tissue

For vascular plants, we have the class:

portion of vascular tissue (PO:0009015): A portion of plant tissue that has parts xylem and phloem. [APweb:Glossary]

Comment: Functions in conduction and support. In the stem it is often found as a stele, surrounded by the cortex and surrounding the pith.

part_of vascular bundle (which is part_of vascular system)

This is okay, but suggest that we make it a child of the new class portion of axial tissue (see below), and also change definition to include xylem or phloem.


Proposed definition: A portion of axial tissue that has as parts tracheary elements or sieve tube members and is part of a vascular system.

Comment: Functions in conduction and support. In shoot axes, vascular tissue is often found as part of a stele or may occur as scattered vascular bundles. May include other types of tissue, such as fibers.

part_of vascular system (should add vascular system participates_in sporophytic phase)

currently part_of vascular bundle. Removed this relation, because it is not true for all plants. Also vascular bundle is now a portion of vascular tissue, so it can't be part_of.


children of vascular tissue:

hydathode (PO:0005660) - A structural modification of vascular and non-vascular tissues, usually in a leaf, that permits the release of water through a pore in the epidermis. [GR:pj, ISBN:0080374913]

Should be is_a cardinal organ part. Do hydathodes ever occur on stems or branches, or are they always part of phyllomes?

proposed definition: A cardinal organ part that releases water through a pore.

Comment: Usually found on leaves. Hydathodes may have one or more pores that appear to be incompletely developed stomata that lack the ability to open and close. Generally, hydathodes are located at the end of a minor vein. In many plants, hydathodes includes a portion of thin-walled parenchyma between the tracheary elements and the pore, known as an epithem. In some plants, hydathodes are associated with secretory tissue.


leaf vein (PO:0005417) - see more below details below


phloem (PO:0005417): A portion of vascular tissue whose principal function is conducting organic substances. [GR:pj]

proposed definition: A portion of vascular tissue that has as parts sieve tube members.

Comment: Functions in the conduction of organic substances in vascular plants.


metaphloem (PO:0006076): Part of the primary phloem that differentiates after the protophloem and before the secondary phloem, if any of the latter is formed.

proposed definition: A portion of phloem tissue that is the part of a primary phloem that differentiates after the protophloem and before the secondary phloem, if any of the latter is formed.


protophloem (PO:0006077): The first-formed elements of the primary phloem.

proposed definition: A portion of phloem tissue that has as parts the first-formed elements of the primary phloem.


tracheid bar (PO:0019026): A distinct ring-like structure, composed of tracheid cells, which surrounds the hilum of some taxa e.g., Phaseolus, and forms a groove in the surface of the pericarp (immediately adjacent to the hilum). [ISBN:0080280293]

-should be is_a xylem


xylem (PO:0005352): A portion of vascular tissue composed of (that has as parts) xylem elements.


vascular bundle (PO:0005020): A unit strand of the vascular system containing the vascular tissues, xylem and phloem. In addition vascular cambium is often present. [GR:pj]

This currently is_a portion of plant tissue. Should be is_a portion of vascular tissue.

proposed definition: A portion of vascular tissue that is a unit strand of the vascular system and has as part xylem or phloem.

Comment: Usually contains both xylem or phloem. May also contain other types of tissue such as plant fibers or vascular cambium. May also contain portions of ground tissue.

part_of vascular system


New children of plant tissue:

hydrome: A portion of axial tissue that has as parts hyrdoids.

Comment: Found in bryophytes, in the center of a non-vascular shoot axis such as a gametophore or seta, or in the midrib of a non-vascular leaf. Often surrounded by leptome. May function in water conduction and support, similar to xylem in vascular plants.

Synonyms: hydrom, leptoxylem (Hebant)


leptome: A portion of axial tissue that has as parts leptoids.

Comment: Found in bryophytes, in non-vascular shoot axes such as a gametophore or seta, or in the midrib of a non-vascular leaf. Often surrounding a central hydrome. May function in the conduction of organic substances, similar to phloem in vascular plants.

Synonyms: leptom, leptophloem (Hebant)


central strand: A unit strand of axial tissue that has as part hydrome or leptome.

Comment: Often contains both hydrome and leptome. Found in bryophytes located in the center of non-vascular shoot axes such as a gametophore axis or seta, or in the costa of a non-vascular leaf.

synonyms: conducting strand, central cylinder


stereome: A portion of axial tissue that has as parts stereids.

Comment: Found in bryophytes.

From Hebant: A typical moss stem comprises, from the outside to the inside, an epidermis with a thin cuticle but no stomata, an outer cortex which frequently consists of supporting ells with thickended walls ("stereids"), an inner cortex of thin-walled conducting cells, and, in a number of species, a central strand of hydroids.


portion of plant fiber: Currently fibers are plant cell types, but they should also be a tissue type.

Proposed definition: A portion axial tissue that has as parts fiber cells.

Comment: Contains elongated, lignified fiber cells that are dead at maturity.

Need to create a term fiber cell that is_a sclerenchyma cell (and also add sclerid)

phloem fiber: A portion of plant fiber that has as parts phloem fiber cells.

xylem fiber: A portion of plant fiber that has as parts xylem fiber cells.

leaf vein, midrib, costa

  • leaf vein (PO:0020138): A strand of vascular tissue in the leaf blade.

is_a portion of vascular tissue; part_of leaf vascular system

This term only applies to vascular leaves, and should be renamed vascular leaf vein.

proposed definition, vascular leaf vein (PO:0020138): A strand of vascular tissue that is part of a leaf lamina in a vascular leaf.

part_of leaf vascular system, part_of leaf lamina


  • Suggest new term primary leaf vein: A vascular leaf vein that originates from the base of a leaf lamina where it attaches to the petiole or to the shoot axis if no petiole is present.

Comment: A leaf may have more than one primary vein. The central primary vein is the midvein.


  • midvein (PO:0020139): The central, and usually the most prominent, vein of a leaf or leaf-like organ. [source: APWeb:Glossary]

Since midvein is_a leaf vein, it should say just "leaf" instead of "leaf or leaf-like organ". Suggest we rename it vascular leaf midvein to distinguish it from costa.

proposed definition of vascular leaf midvein: A primary leaf vein that is the central vein of a leaf lamina in a vascular leaf.

Comment: Often the most prominent vein of a vascular leaf.

broad synonyms: mid rib, midrib, mid-rib

related synonym: costa, Hickey and Peterson 1978 doi:10.1139/b78-128


  • Moss Ontology has requested the term midrib for bryophytes. It is often called a costa.

Proposed definition for costa:' A central strand that is part of a non-vascular leaf.

Comment: Found in bryophytes, especially mosses.

part_of non-vascular leaf

broad synonyms: mid rib, midrib, mid-rib

Refs:

Sperry 2003, IJPS; Hebant 1977;

Continuing User requests: for PSO

- Deal with and complete the list of user requests on SourceForge-

Legume terms

submitted by Austin Mast

Several terms have already been dealt with (Taproot, Stem Hair, Prickles, Anther pore and anther slit)

fascicle The term fascicle can refer to different structures in different taxa. Suggest we use the term floral fascicle or flower fascicle in this case, to distinguish it from a "leaf fascicle," which we may want to add for describing gymnosperms.

From Tucker, 2003, Flora: (in the Papilionoideae) "Pseudoracemes (Fig. 5B) differ from racemes in that two to several flowers are initiated in each bract axil rather than just one as in a raceme. The cluster of flowers at each node is called a fascicle. The order of initiation among flowers at a node (Fig. 5B, Psoralea macrostachys DC) shows the fascicle to be a short shoot topped by a second order inflorescence apical meristem. This meristem initiates flowers in a bilaterally symmetrical order: a single abaxial flower, then two lateral flowers, another median abaxial, then two more laterals. The number of flowers per fascicle depends on the duration of the axillary inflorescence apex of the short shoot, which ceases activity after initiating the few flowers in the fascicle. No flowers are initiated adaxially (toward the first order axis) on the short shoot (Tucker, 1987b; Tucker and Stirton, 1991). The short shoot in a pseudoraceme can be distinguished from a cyme in that every flower is bract subtended in a pseudoraceme."

Proppsed def: A second order inflorescence in which the second order inflorescence branch bears two or more flowers but is not elongated. Comment: A fascilce appears to be a cluster of flowers in an axil of a single bract of the main inflorescence. Common in some sections of the Fabaceae.


bristle (used in key as "Stipules spinose or bristles"; might be thought of as a quality, rather than a structure)

We added the term stipule spine. Could also add the term stipule bristle: A stipule that has a brush-like appearance.

Alternative is to suggest bristled to PATO


phyllode

Proppsed def: A leaf in which there is no normal lamina development, but instead the petiole or petiole plus rachis is laminar.


banner, wing and keel

Banner (as in a legume flower) - suggest using name 'banner petal'

Proppsed def: A petal that is the top-most petal of a corolla in some flowers of the Fabaceae. Comment: The banner is usually larger than the adjacent wing petals.


Wing (as in a legume flower) - suggest using name 'wing petal'

Proppsed def: One of two petals that is adjacent to the banner petal in some flowers of the Fabaceae. Comment: The wing petals are usually much smaller than the banner petal and the corolla keel.


Keel (as in a legume flower): The keel consists of two fused petals, and is analogous to the fused collective tepal structure we made for Musa. Maybe name 'corolla keel'

Suggest three new terms:

fused petal: A petal that is fused to another petal.

Comment: May be fused to two petals (one on either side). This is a phenotype that is a cross-product of PO:0009032 (petal) and PATO:0000642 (fused with).


fused corolla: A corolla in which the petals are fused.

Comment: This is a phenotype that is a cross-product of PO:0025023 (collective phyllome structure) and PATO:0000642 (fused with). A corolla may consist of a combination of fused and free petals, in which case fused corolla only refers to those petals that are fused.


corolla keel: A fused corolla that consists of the two lowest petals in some flowers of the Fabaceae.

Comment: The two petals of the keel may be fused at the apex but free at the base. The remaining three petals (banner and two wings) are free. The keel is boat shaped.

TraitNet requests

corm

proposed def: A short, enlarged storage stem in which the internodes do not elongate. Comment: usually underground.

child of stem (PO:0009047).


podarium

Their comment: is synonym to Tubercle

podarium (from Beentje 2010): (in cacti or other succulents) a modified leaf base functioning as the photosynthesising organ.

tubercle (from Beentje 2010): (in ball- or barrel- shaped cacti), cone-shaped protuberances that are elnarge modified leaf bases fused with adjacent stem tissue (tubercle has two other definitions as well).

proposed def:


pneumatophore

definition from Beentje (2010): erect (breathing) root protruding above the soil, encountered especially in mangroves

proposed def: A root that is erect and protrudes above the soil, found in trees that live in flooded habitats such as mangroves. Comment: Pneumatophores may provide oxygen to below ground roots growing in flooded soils.


diaspore

definition from Beentje (2010): reproductive portion of a plant, such as a seed, fruit or fragment of fruit, that is dispersed and may give rise to a new plant.

We could add this term as a kind of upper level bin term (similar to trichome)


cone

Should probably be a synonym of strobilus (PO:0025083). Narrow or exact?


sorus

from Crum (2001): a cluster of fern sporangia from Beentje (2010): (of pteridophytes) structure bearing or containing groups of sporangia.

Proposed definition: A cardinal organ part composed of a cluster of two or more adjacent sporagia on the surface of a leaf. Comment: May be enclosed by an indusium.

Part_of vascular leaf, has_part sporangium


tendril

Defintion from Beentje (2010): a slender, coiling structure derived from a branch, leaf or inflorescence and used for climbing.

tendrils can derived from multiple types of structures. Suggest we make separate terms:

branch tendril (child of branch): A branch that is slender and coiling. Comment: Aids plant in climbing.

leaf tendril (child of leaf): A leaf that is slender and coiling and lacks a lamina. Comment: Aids plant in climbing.

leaflet tendril (child of leaflet): A leaflet that is slender and coiling. Comment: Aids plant in climbing.

leaf apex tendril (child of leaf apex): A leaf apex that is slender and coiling. Comment: Aids plant in climbing.

Can add other types of tendrils if they come up or users need them.

root terms

submitted by Rich Zobel (Nov 2009)

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.


User requests still open on Source Forge; PGDSO

tuber growth and development stages

This item has been open on SF since 6/2009

I have a bunch of potato genes which are expressed in different tuber developmental stages (e.g. the potato pmt gene is expressed in small sprouts only (http://www.ncbi.nlm.nih.gov/pubmed/16088399).

Suggested stages:

-sprout development (does this correspond to tube axillary bud development? Should come after tuber maturation)

-tuber initiation

-tuber growth

-tuber maturation

How we work these in will depend on restructuring of PGDSO

l development in legumes (Plant Physiol, March 2003, Vol. 131, pp. 911-926

terms for seed development stages

This is a fairly new request for terms for cotton