plant dev glossary Flashcards
adventitious roots
roots that rise in unusual positions e.g. from stem or leaf
annual
plants preform their entire life cucle in a single growing season
apical meristem
the highest or most extreme meristem on a shoot or root
axilliary bud
a bud located at the intersection of a stem,leaf etc
what is a biennial and its pattern
plant that requires up to two years to complete the life cycle typical pattern is germinates in spring grows over summer and Autumn, vernalised in winter and seeds flowers and dies in the second spring/summer
cotyledons
a seed leaf that is part of the plant embrio and contains a large portion of the feed reserves
crowm
top part of a tap root of an herbaceous plant where meristems that generate primary stems are situated.
cultivar
a group of plants from one species that are distinctive distinguishable from each other
day neutral plant
a plant which flowering is not effected by day length
determinate growth
when the apical meristem of a shoot becomes reproductive. terminates the life of this shoot
dicotyledons or dicots
One major type of flowering plants (angiosperms); they have 2 cotyledons in their seeds; some are herbaceous
(e.g. clovers, buttercups) & some are woody; some are evergreen
emergence
The appearance of a seedling through the soil surface
ephemeral plant
extreme annual. goes from seed to seed in a few weeks
epicotyl
The part of the seedling above the cotyledons; it will develop into the shoot
epigeal germination
when cotyledons are carried above the soil
floret
a group of flowers
germination
the physilogical process after the uptake of water by a dry seed. will result in roots and a seedling
harvest index
part of the economical useful part of the plant expressed as the portion above the ground or the useful part of there root for root crops
hypogeal germination
when the cotyledons stay beneath the ground
intermediate growth
when the apical meristem remains vegetative and only lateral meristems turn reproductive thus flowering occurs over a longer period.
induction
the physical change due to the environment triggers such as changing photo period or chilling that allows for the development of reproductive cells
inflorescence
the way the plant groups its flowers
legume
herbage and grain plants and fabaceae most have root fixing nodules and nitrogen fixing rhizobium
ligule
thin membrane at the junction of a leaf blade and sheath of grass
meristem
a part of the plant where cell division is concentrated.
perennial
lives for more than two seasons.
photoperiodism
In many plant species, floral induction occurs in response to changing day length or photoperiod.
phytochrome
the protien pigment found in plants, it is a photo-receptor for red and far red light that is invovled with a number of timing processes.
phytomer
a basic module or building block of plant growth consisting of a: node, leaf, axillery bud and joined to the next phytomer by an inter node.
population density
The number of plants per unit area of ground
primary roots
or seminal roots, develop from seedling axis
Rhizobium
bacteria that colonize legume roots that convert atmospheric nitrogen into ammonia for use by the
legume
secondary growth
Growth arising from the cylindrical cork cambium meristem that causes an increase in girth of stems & roots of
woody dicots
spikelet
The basic unit of a grass flower, consisting of 2 glumes or outer bracts at the base and one or more florets
above
stratification
seed require a cold moist period before germination so that it doesn’t occur in winter. can be induced artificially.
summer annual
germinates in spring grows flowers and seeds over summer before it dies in autumn
tiller
the functional unit of a grass plant: true stem, leaves and roots. after parent tiller grows from a seed tillering occurs from dromant axillary buds of phytomers that receive red light signal.
vernalisation
the induction or promotion of flowering through exposure to low tempratures.
winter annual
plant that germinates in Autumn grows vegetatively and is vernalised over winter flowers in spring and dies early-mid summer.
