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A
Abscission:
The shedding of leaves, flowers, or fruits following
the formation of scar tissue in a plant. A bscisic
acid is the plant hormone involved in leaf abscission.
Acid:
A substance that has a pH of less than 7, which is
neutral. Specifically, an acid has more free hydrogen
ions (H + ) than hydroxyl ions ( OH - ).
Active
transport : Transport of molecules against
a concentration gradient (from regions of low concentration
to regions of high concentration) with the aid of
proteins in the cell membrane and energy from ATP.
Adenosine
triphosphate (ATP) : A common
form in which energy produced in the light reaction
of photosynthesis stored in living systems; consists
of a nucleotide (with ribose sugar) with three phosphate
groups.
Adsorption
: The accumulation of gases, liquids, or
solutes on the surface of a solid or liquid. The attachment
of nutrient ions to the surface of clay and organic
colloids within soil.
Aerobic
respiration : Respiration in which molecular
oxygen is consumed and carbon dioxide and water are
produced. Opposite of anaerobic respiration.
Aeroponics
: A variation of hydroponics that involves
the misting of plant roots with nutrient solution.
Commonly used in cloning machines, but can be used
for full term growth. Advantageous due to the higher
levels of oxygen present in the root zone. It also
reduces the amount of energy a plant uses to uptake
nutrient by delivering food and water in small drops
as opposed to the water accumulating on the root for
absorption.
Affinity
: An attractive force between two particles.
Algae
: Any of various chiefly aquatic, eukaryotic,
photosynthetic organisms, ranging in size from single-celled
forms to giant kelp.
Alkaline
: or, basic. Having a pH greater than 7.
Having a relatively low concentration of hydrogen
ions
Alkalinity
: The alkali concentration or alkaline quality
of an alkali-containing substance.
Amino
acid : A ny one of a class of simple organic
compounds containing carbon, hydrogen, oxygen, nitrogen,
and in certain cases sulfur. These compounds are the
building blocks of proteins and enzymes. They are
characterized by the presence of a carboxyl group
(COOH) and an amino group (NH2) attached to the same
carbon at the end of the compound.
Ammonium
nitrate : C hemical compound, NH 4 NO 3 ,
that exists as colorless, rhombohedral crystals at
room temperature but changes to monoclinic crystals
when heated above 32°C. It is extremely soluble
in water and soluble in alcohol and liquid ammonia.
It is prepared commercially by reaction of nitric
acid and ammonia . Major uses are in fertilizers and
explosives . For fertilizers it is in the form of
small clay-coated pellets. For explosives it is sometimes
mixed with other substances, e.g., TNT, so that it
is more easily detonated. It is also used in solid-fuel
rocket propellants, in pyrotechnics, and in the production
of nitrous oxide.
Ampere
(AMP): this is the unit used to measure
strength of an electric current.
Anaerobic
respiration : Respiration in which molecular
oxygen is not consumed.
Angiosperms
: a flowering plant
Animal
welfare : The health and well being of animals
is central to organic principles. Health should be
defined as a positive physical and mental state whereby
the livestock are robust and able to resist diseases.
Positive animal welfare means the satisfaction of
'all the animals' needs, including their behavioral
needs, not just the avoidance of cruelty. The foundation
stones of animal welfare are good nutrition, careful
management and the use of appropriate breeds.
Anions
: Anions are negatively charged ions such
as sulfate SO 4 - and phosphate PO 4 -
Annual
: Maturing and living one season only.
Anther
: The pollen producing tip of a stamen; part
of a flower.
Apical
meristem : Group of cells at the growing
tip of a branch or root. It divides cells to create
new tissues.
Apoplast
: The extracellular region that includes
the cell wall and middle lamella. The apoplast is
found in the non-living parts of the root.
Aquaculture
: F arming of plants and animals that live
in water, such as fish, shellfish, and algae. The
other end of the system from plant growth when growing
aquaponically
Aquaponics
: The integration of aquaculture (the raising
of marine animals, such as fish) with hydroponics;
the waste products from the fish are treated and then
used to fertilize hydroponically growing plants.
Arable
: Suitable for plowing.
Arthropods
: Invertebrate animals with jointed legs.
They include insects, crustaceans, sowbugs, springtails,
arachnids (spiders), and others.
Asexual
reproduction : In asexual reproduction (gemmation,
fission, etc.), the detached portions of the organism
develop into new individuals without the intervention
of other living matter.
Assimilation
: To absorb and incorporate; digest.
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B
Bacteria
: Primitive, unicellular, microscopic organisms
that lack a cell nucleus and other organelles, obtain
soluble food by absorption, and reproduce by simple
cell division. They include the photosynthetic cyanobacteria
(formerly called blue-green algae), and actinomycetes
(filamentous bacteria that give healthy soil its characteristic
smell). T hese are the most abundant
of all organisms --and the simplest (having only a
single cell). They are beneficial to decay mechanisms,
but many kinds are considered disease organisms. Examples
of bacterial diseases include blights and some types
of rot and wilt.
Ballast
: a device used to regulate flow of electricity
to match the needs of a specific bulb.
Base
: A substance that has a pH of more than 7, which
is neutral. A base has less free hydrogen ions (H
+ ) than hydroxyl ions ( OH - ).
Binding
site : region on a protein where specific
ligands bind.
Biocatalyst
: A substance, especially an enzyme, that
initiates or modifies the rate of a chemical reaction
in a living body; a biochemical catalyst.
Biodiversity
: The diversity of living organisms in any
one place --whether in a handful of soil, the garden,
the region, or the planet. Species richness contributes
heavily to a healthy environment on every level, creating
balance through an elegant distribution of the work
of the planet. Diversity helps to insure that a single
pest, event, or disease doesn't cause irreparable
damage to an entire ecosystem. In the same way, growing
a variety of crops while supporting a diverse community
of organisms will help insure you a successful harvest
year after year.
Biodynamic
cultivation : Originated by Rudolph Steiner,
it is a form of cultivation that originates through
Eastern philosophy and cosmic influences and has been
referred to as "spiritual science".
Biological
control : A term used to describe the use
of natural organisms to reduce the effects of undesirable
organisms (pests) and to favor desirable organisms
such as crops, trees, animals, beneficial organisms
or insects.
Biostimulant
: a substance that is not a plant nutrient
or pesticide but which in some manner has a positive
impact on plant health. The biostimulant may enhance
metabolism, increase chlorophyll efficiency and production,
increase antioxidants, enhance nutrient availability
and increase the water holding capacity of the soil.
Biosythesis
: Formation of a chemical compound by a living
organism. Also called biogenesis.
Blight
: Affecting a long list of different plant
species, each in a slightly different manner, blight
is a bacterial disease. The disease spreads rapidly
in wet conditions, generally turning whole or parts
of leaves brown and black. Highly contagious: if you
suspect your plants are suffering from blight, trim
off dead or dying plant material at least two inches
below infected material, sterilizing your pruners
between each cut.
Blood
meal : This organic fertilizer is very high
in nitrogen and is very soluble in water (unlike most
other dry organic fertilizers). It also contains plant
growth regulators. All this together means that its
effect is strong and quick, but its power will only
last a short while, especially in wet weather. When
applying blood meal, take care, as it will easily
burn a plant's leaves.
Bone
meal : An organic fertilizer that is applied
to increase phosphorus levels in the soil (or compost).
Although phosphate rock can also be used for this,
bone meal will break down in the soil considerably
faster and can thus be used as a quick fix; but this
also means that it will not have a long term effect
on the soil.
Bryophyte
: Plant that lacks vessels, including the
mosses, liverworts, and hornworts.
Burn
: Leaf tips that turn noticeably dark from
excess fertilizers or salts. Usually occurs from the
edges or tips of leaves and is a result of "water
stress". Water stress occurs from the reversal of
the gradient plants use to utilize water via osmosis.
By having too high a concentration of ions outside
the root, water goes from a lower to a higher concentration,
leaving the plant, in turn, "burning" it.
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C
Calvin
cycle (aka Calvin-Benson Cycle or Carbon
Fixation): The non-light requiring reactions (dark
reactions) of photosynthesis. Series of biochemical,
enzyme-mediated reactions during which atmospheric
carbon dioxide is reduced and incorporated into organic
molecules, eventually some of this forms sugars. In
eukaryotes, this occurs in the stroma of the chloroplast.
Calyx
: The calyx is the outermost whorl of a flower.
It consists of sepals , which are green.
The sepals may be free from each other in the same
flowers of some plants or fused to form a cup in flowers
of other plants. The calyx encloses and protects the
inner whorls in the bud stage . Since the sepals contain
chlorophyll, they can also synthesize food
Cambium
: Primary growth in plants is accomplished
by the apical meristem, which accomplishes the elongation
of the plant. Secondary growth is made possible by
the lateral meristem, which increases the girth of
the plant. This actively growing tissue is generally
only present in woody species and is called the cambium.
It produces secondary xylem and phloem.
Canopy
: Layer of vegetation elevated above the
ground, usually of tree braches and epiphytes. In
tropical forests, the canopy may be more than 100
feet above the ground. In indoor gardening it is simply
the uppermost level of vegetation.
Capillary
action : T he means by which liquid moves through
the porous spaces in a solid, such as soil or plant
roots due to the forces of adhesion, cohesion, and
surface tension. Capillary action is essential in
carrying substances and nutrients from one place to
another in plants.
Carbohydrate
: Any of a group of organic compounds that
includes sugars, starches, celluloses, and gums and
serves as a major energy source in the diet of plants
and animals. These compounds are produced by photosynthetic
plants and contain only carbon, hydrogen, and oxygen,
usually in the ratio 1:2:1. Glucose is the major plant
carbohydrate and the end product of photosyntheis.
Carbon
cycle : The Carbon Cycle is a complex series
of processes through which all of the carbon atoms
in existence revolve and rotate.
Carbon
dioxide : A heavy colorless gas that does
not support combustion, dissolves in water to form
carbonic acid, is formed in respiration and in the
decay or combustion of animal and vegetable matter.
It is absorbed from the air by plants in photosynthesis,
being the primary source of Carbon for growing plants.
It occurs naturally in the atmosphere at .03%.
Carbon-Nitrogen
ratio : The ratio of the weight of organic
carbon to the weight of total nitrogen (mineral plus
organic forms) in soil or organic material. Usually
referred to in regards to composting. Needs to be
30:1, or 2:1 by weight, for proper decomposition for
composting.
Casparian
Strip : A layer in endodermis that functions
as a selective barrier allowing absorption of desirable
elements, but blocking absorption of harmful elements.
Made up of suberin, it is impervious to water. Named
after its discoverer.
Catabolism
: The metabolic breakdown of complex molecules
into simpler ones, often resulting in a release of
energy.
Catalyst
: A catalyst is a substance that increases
the speed of a chemical reaction without being consumed
or altered by the reaction.
Cations
: Cations are positively charged ions such
as calcium Ca + , Magnesium Mg + , and Sodium Na +2
.
Cation
Exchange Capacity (CEC): The clay and organic
components of the soil have a negative charge. As
a result of these charges, positively charged ions
(cations) such as hydrogen H + , potassium K + , ammonium
NH + 4 , calcium Ca 2+ , magnesium Mg 2+ , aluminum
Al 3+ , etc. may be held at the surface of the clay
or organic particles and exchanged with other ions
in the solution or with ions at the plant root's surface.
This ability of a soil to hold cations is termed its
cation exchange capacity (CEC). Since many cations
are plant nutrients the cation exchange capacity is
a measure of the soil's ability to hold such nutrients.
Expressed in milliequivalents per 100 grams or per
gram of soil (or other exchangers such as clay).
Cell
: Fundamental structural unit of all life.
The cell consists primarily of an outer plasma membrane,
which separates it from the environment; the genetic
material (DNA), which encodes heritable information
for the maintainance of life; and the cytoplasm, a
heterogeneous assemblage of ions, molecules, and fluid.
Cellulose
: A polysaccharide made up of many glucose
molecules chemically bonded together. The most abundant
compound on earth. It comprises the bulk of cell walls
of plants where it occurs as microfibrils.
Charge
: The state of an atom that has lost or gained
an electron.
Chelate
: A chemical compound in the form of a heterocyclic
ring, containing a metal ion attached by coordinate
bonds to at least two nonmetal ions; can be in the
form of humic acids, fulvic acids, or amino acids.
Chemical
fertilizer : Defined as any inorganic material
of wholly or partially synthetic origin that is added
to the soil to sustain plant growth. Many artificial
fertilizers contain acids, such as sulfuric acid and
hydrochloric acid, which tend to increase the acidity
of the soil, reduce the soil's beneficial organism
population and interfere with plant growth.
Chemical
specificity : The ability of a proteins binding
site to bind specific ligands; the less ligands a
protein can bind, the greater its specificity.
Chemiosmotic
phosphorylation : The process where energy from
oxidations is used to separate H+ ions across a protein
gradient to produce ATP. Also referred to as oxidative
phosphorylation.
Chlorophyll
: The green pigment of plant cells necessary
for photosynthesis that captures light energy and
converts it into chemical energy. Found in the chloroplasts
of plant cells. It is the pigment that makes plants
green because it absorbs red and blue and reflects
green. Chlorophyll is highly efficient at absorbing
light energy, and is essential to photosynthesis.
Chloroplast
: An organelle containing chlorophyll. There
are many "organelles" that contribute to
the function of a single cell. In plants cells, the
organelle that carries out photosynthesis is called
the chloroplast.
Chlorosis
: A condition in plants resulting from the
failure of chlorophyll to develop caused by a deficiency
of an essential nutrient. Leaves of chlorotic plants
range from light green through yellow to almost white.
Chlorosis may be a symptom of a number of different
plant ailments, including mineral deficiencies (commonly,
iron) and some diseases. It occurs as a result of
reduced chlorophyll production, turning newer (usually)
growth yellow. In established leaves, areas between
the veins yellow first.
Clay
: A sedimentary material with grains smaller
than 0.002 millimeters in diameter.
Clone
: A plant that has been produced through
asexual reproduction (i.e. cuttings, layering, and
tissue culture) and is an exact replica of the "mother"
plant.
Cloning
: A cell, group of cells, or organism that
are descended from and genetically identical to a
single common ancestor, such as a bacterial colony
whose members arose from a single original cell. An
organism descended asexually from a single ancestor,
such as a plant produced by layering or a polyp produced
by budding.
Coenzyme
: A nonproteinaceous organic substance that
usually contains a vitamin or mineral and combines
with a specific protein, the apoenzyme, to form an
active enzyme system.
Cofactor
: A substance, such as a metallic ion or
coenzyme, which must be associated with an enzyme
for the enzyme to function.
Collenchyma
cells: Collenchyma tissues are mainly found
under the epidermis in young stems in the large veins
of leaves. The cells are composed of living, elongated
cells running parallel to the length of organs that
it is found in. Collenchyma cells have thick cellulose
cell walls which thickened at the corners. Intercellular
air spaces are absent or very small. The cells contain
living protoplasm and they sometimes contain chloroplasts.
Primary function is strengthening and supporting the
developing plant.
Color-rendering
Index (CRI): Color rendering is a measure
of lighting quality. It is measured on an index from
0-100, with natural daylight equal to 100. Lamps with
a high color-rendering index make objects appear more
true to life. Plants can grow better with a higher
color rendering index light source. But generally
the higher the CRI the lower the lamp efficiency.
Hence, MH light being closer to sunlight relative
to HPS, but emitting less lumen per watt, or relative
amount of light. A CRI of 85 or higher is considered
good.
Color
Temperature : Color temperature is a measure
of the color appearance of light not the actual temperature.
Light sources that appear bright white to blue-white
have a high color temperature (3600K and above) and
are described as "cool". Sources that appear
yellow-white to red-white have a low color temperature
(3600K and below) and are described as "warm".
Daylight is considered to be around 5500K.
Companion
planting : Utilizing the symbiotics and interrelationships
of various plants to replicate a balanced ecosystem
so as to accumulate predators and prey in the same
areas therefore creating a check and balance system
so as to control pest and disease problems.
Complete
fertilizer: Containing all of the necessary
elements a plant needs to grow. Miracle Grow, Peter's,
etc. are not complete because they rely on the soil
to bring the completion of fertilization. Products
that are not "complete" will result in extreme deficiencies
in plant growth and eventual non-production is utilized
in a soilless scenario.
Compost
: By piling kitchen scraps and garden debris
in a bin or heap, gardeners create an ideal habitat
for decay organisms. These microorganisms break organic
material down to form humus. In addition, the heat
inside the pile from all the biologic activity will
kill off many disease organisms and unwanted seeds.
Compost piles benefit from the addition of manures
(for their high nitrogen count and the beneficial
bacteria they harbor), occasional watering (so that
it is moist not wet), and frequent turning (for aeration).
Compost
tea : An infusion made by leaching water
through compost, sometimes with nutrients added, such
as molasses and kelp, to encourage certain organisms. Soluble
organic matter and the organisms in the compost are
rinsed out of the solid phase and left suspended in
the water. This "liquid compost" is
easier to apply than solid compost.
Corolla
: The corolla is the "flower" part of the
flower. It is often brightly of conspicuously colored
and/or creating inviting aromas so as to attract beneficial
insects to help in pollination.
Cortex
: The cell layers occurring between the epidermis
and the stele or vascular cylinder.
Cotyledon
: The "seed leaves" or "starter
leaves" produced by a seed plant embryo. They serve
to absorb nutrients packaged in the seed, until the
seedling is able to produce its first true leaves
and begin photosynthesis.
Covalent
bond : A chemical bond formed by the sharing
of one or more electrons, especially pairs of electrons,
between atoms.
Cover
crop : A crop, such as winter rye or clover,
planted between periods of regular crop production
to prevent soil erosion and provide humus or nitrogen
for the next planting. Cover crops have become interchangeable
with green manures.
Cross-pollination
: Transferring pollen from the flowers of
one plant of a species to the stigma of another plant
of the same species. In other words, from pepper plant
to pepper plant. The crossing of different types of
pepper plants can result in trouble identifying or
maintaining the strain.
Current
: Current is what flows on a wire or conductor,
like water flowing down a river. Current flows from
points of high voltage to points of low voltage on
the surface of a conductor. Current is measured in
(A) amperes or amps.
Cuticle
: Waxy layer which seals the outer surface
of land plants, helping to retain moisture.
Cytokinin
: any of a class of plant hormones that promote
cell division and growth and delay the senescence
or aging of leaves.
Cytoplasm
: the substance inside a cell which surrounds
the cell's nucleus
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D
Damping-off
fungus : Disease that attacks young seedlings
and cuttings causing stem to rot at base. Over watering
and cool wet soils favor development of the disease.
The damping-off fungi may attack the seed prior to
germination, or they may attack after the seed has
germinated but before the seedling has emerged above
the soil line. Infected seed becomes soft and mushy
turning a brown to black color, and it eventually
disintegrates. Seeds that have germinated and become
infected develop water-soaked spots that enlarge and
turn brown. The infected tissue collapses, resulting
in death of the seedling. Penetration and death of
seeds before they emerge is termed preemergence damping-off.
Dark
reaction : The photosynthetic process in
which food (sugar/carbohydrate) molecules are formed
from carbon dioxide from the atmosphere with the use
of ATP and NADPH; can occur in the dark as long as
energy source is present.
DDT
: (C14H9Cl5) Dichlorodiphenyltrichloroethane;
a colorless contact insecticide, toxic to humans and
animals when swallowed or absorbed through the skin,
that has been banned in the United States for most
uses since 1972, mostly as a result of Rachel Carson's
book "Silent Spring".
Decomposition
: The biochemical breakdown of organic matter
into organic compounds and nutrients, and ultimately
into its original components. Results in humus, the
lowest form of organic decomposition.
Deductive
reasoning : Reasoning from the general to
the particular (or from cause to effect).
Desalinization
: T he removal of salts from saline water
to provide freshwater. This method is becoming a more
popular way of providing freshwater to populations.
Israel leads the world in this technology.
Determinate
growth : not continuing to grow indefinitely
at the apex.
Detritus
: Loose matter resulting from the wearing
away or disintegration of a tissue or substance.
Dicots
: A flowering plant with two embryonic seed
leaves or cotyledons that usually appear at germination.
Dioecious
: A plant species is said to be dioecious
when its male and female reproductive organs are carried
on separate individual plants of the same species.
When a plant species is dioecious, at least one male
plant must be present in a group for the fruit-bearing
female plants to be pollinated. By contrast, "monoecious"
plants are plants having unisexual reproductive organs
or flowers, with the organs or flowers of both sexes
borne on a single plant.
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E
Ecosystem
: A term used to describe a system of interactions
between living organisms occupying the same environment.
Effluent
: Something that flows out or forth, especially
a stream flowing out of a body of water, an outflow
from a sewer or sewage system, or a discharge of liquid
waste, as from a factory or nuclear plant.
Electrical
conductivity (EC): the ability of a solution
to carry electrical energy as a result of the elements
and compounds in solution. The more ions dissolved
in solution the higher the EC. 1.0 EC is equivalent
to 700 PPM.
Electric
circuit : A closed path followed or capable
of being followed by an electric current. A configuration
of electrically or electromagnetically connected components
or devices.
Electron
transport : C oupled series of oxidation/reduction
reactions during which ATP is generated by energy
transfer as electrons move from high reducing state
to lower reducing state.
Embolism
: Air bubbles can form in the vessels that
transport the water taken up through the xylem towards
the aboveground parts of the plant after taking a
clone and exposing it to air for too long. This results
in the plant being unable to begin the process of
root development and subsequent death. A rooting gel
9as opposed to powder) or taking a cutting under water
are two ways to help prevent embolism and bolster
success rate.
Embryo
: An organism in its early stages of development,
especially before it has reached a distinctively recognizable
form.
Endemic
: Prevalent in or peculiar to a particular
locality or region, as in a disease or plant. For
example, Venus flytraps are endemic to a 50-mile radius
around Wilmington, NC.
Endodermis
: The innermost layer of cortical cells ("inner
skin") found in all roots next to the vascular cylinder.
The endodermis contains a Casparian strip.
Enzyme
: Any of numerous proteins or conjugated
proteins produced by living organisms and functioning
as biochemical catalysts.
Epidermis
: The outer most layer of cells of a growing
plant.
Epiphyte
: A plant that grows upon another plant.
The epiphyte does not "eat" the plant on
which it grows, but merely uses the plant for structural
support, or as a way to get off the ground and into
the canopy environment.
Essential
oils : a class of volatile oils, extracted
from plants, fruits, or flowers, having each its characteristic
odor, and hot burning taste. They are used in essences,
perfumery, etc., and include many varieties of compounds.
Essential oils make a watermelon jucier and a strawberry
sweeter.
Eukaryote
: A single-celled or multicellular organism
whose cells contain a distinct membrane-bound nucleus.
Evaporation
: T he process of liquid water becoming water
vapor, including vaporization from water surfaces,
land surfaces, and snow fields, but not from leaf
surfaces- this is termed transpiration.
Exudate
: A substance that oozes from plant pores.
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F
Fair
Trade: Fair trade certifiers examine the
practices of farmers and companies looking for a commitment
to social justice. Parameters include: Paying a fair
wage in the local context, offering employees opportunities
for advancement, providing equal employment opportunities
for all people, particularly the most disadvantaged,
engaging in environmentally sustainable practices,
being open to public accountability, building long-term
trade relationships, providing healthy and safe working
conditions within the local context, providing financial
and technical assistance to producers whenever possible.
Fishmeal
: Like fish emulsion, fishmeal is high in
nitrogen, but its NPK ratio is generally a bit more
potent, at somewhere about 5-3-3. And, unlike the
emulsion, fishmeal is a dry organic fertilizer.
Flower
: Collection of reproductive structures found
in flowering plants.
Foliar
feeding : Using a mister or spray bottle
to deliver fertilizer solution or other plant promoting
materials directly to the foliage. Used primarily
as a deficiency correction technique, but used outside
of deficiency is just another level of feeding.
Food
security : When all people at all times have
both physical and economic access to sufficient food
to meat their dietary needs for a productive and healthy
life.
Foodshed
:
Footcandle
: A unit of illumination equal to the intensity
of one candle at the distance of one foot.
Fruit
: In flowering plants, the structure which
encloses the seeds. True fruits develop from the ovary
wall, such as bananas and tomatoes, though not all
fruits are edible, such as the dry pods of milkweed
or the winged fruits of the maple.
Fungus
: A non-photosythetic, chiefly multicellular
organism only able to use carbon, nitrogen, etc. as
starting materials for synthesis of its essential
foods. Some are good (mycchorizae), some are bad (fusarium).
Fusarium
: any of several fungal diseases that afflict
plants; commonly called dry rot or wilt.
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G
Gall
: Crown gall infection is caused by various
bacteria of the genus Agrobacterium. The disease affects
a wide range of plants including deciduous fruits,
vine and berry fruits, vegetables and ornamentals.
Within these groups of plants there is no known cultivar
resistance. The bacterium infects the plant through
a wound, usually at ground level or on the roots,
and transfers a tumerogenic (cancerous) factor to
some plant cells. These cells then start dividing
uncontrollably, forming galls of undifferentiated
tissue that restrict the normal functions of the plant.
Gametophyte
: P hase of plant life cycles in which the
gametes, i.e., egg and sperm, are produced. A gametophyte
is the haploid structure or phase of life of a sexually
reproducing plant. Each cell of a gametophyte contains
one complete set of chromosomes. The gametophyte can
be the dominant part of the plant's life cycle as
in mosses, or very reduced as in flowering plants
(angiosperms), where the female form (ovule) is known
as a megagametophyte and the male form (pollen) is
called a microgametophyte.
Genetically
Modified Organism (GMO): The 41st Edition
of the International Air Transport Association Dangerous
Goods Regulations defines GMOs as microorganisms and
organisms in which genetic material has been purposely
altered through genetic engineering in a way that
does not occur naturally. http://www.biotechmedia.com/definitions-g.html#GMO
Germination
: The process of causing the initiation of
a plant from seed. A seed will germinate, or sprout,
when conditions are right for survival. These conditions
include: adequate moisture, heat, and/or light. The
germinating seed sends its first root (radicle) into
the soil and the first stem with the first leaves
(cotyledon) toward the sun. Some seeds require pretreatment,
such as scarring or soaking, before they will germinate.
Gleaning
: Literally meaning, "to collect grain by
leapers", gleaning has come to be known as the collective
redistribution of food, especially potentially wasted
food.
Glucose
: A product of photosynthesis and an important
source of physiological energy for plants and animals.
Glucose is a sugar, or carbohydrate.
Glycolysis
: An ATP-generating metabolic process that
occurs in nearly all living cells in which glucose
is converted in a series of steps to pyruvic acid.
The metabolic breakdown of glucose and other sugars
that releases energy in the form of ATP.
Gravitropism
: Gravitropism is a plant growth response
to gravity. Plant shoots display negative gravitropism.
When placed on its side, a plant shoot will grow up.
Roots display positive gravitropism, they grow down.
Green
manure : Crops grown for fertilization, not
production. Green Manure's are traditionally crops
that are grown to turn into the soil, mostly for a
nitrogen source. Word has become interchangeable with
cover crops.
Greensand
: Greensand is mined from ancient seabeds;
it is a dry organic fertilizer. It is useful for its
ability to slowly supply to the soil a number of different
micronutrients, as well as potassium.
Grounded
: A large conducting body, such as the earth
or an electric circuit connected to the earth, used
as an arbitrary zero of potential. A conducting object,
such as a wire, that is connected to such a position
of zero potential.
Guard
cells : The Guard cells control the stomatal
openings in the epidermis of the leaf. Three environmental
factors regulate these cells. These factors are light,
CO2 concentration and water availability. When the
guard cells are activated, K+ pumps actively transport
K+ into the guard cells, resulting in a high [K+]
in the cells. As a result, water enters the cells
by osmosis. This causes the guard cells to swell.
The one side of the guard cells is thicker than the
other and does not stretch. As the guard cells swell
up they bend. When the stoma is open CO2 can diffuse
into the leaf and enter the Calvin Cycle. The oxygen
produced in photolysis, diffuses out of the open stoma.
Water vapor also escapes from the stoma by the process
of transpiration. As water transpires, other water
molecules are pulled up through the plant behind it.
Gymnosperms
: non-flowering plants
Gypsum
: Gypsum, which occurs naturally in sedimentary
rocks, is a dry organic fertilizer that supplies two
important micronutrients: calcium and sulfur.
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H
Hardpan
: Although hardpans can occur naturally,
they are often caused by repeated compaction of soil
particles (such as with the tires of heavy equipment).
Soils particularly prone to hardpan are usually heavy
in clay. A hardpan will prevent adequate drainage
and, depending on its depth, it may stunt or cause
malformed root growth. Correct hardpans by double
digging, aerating it with a broadfork or spading fork,
or for bigger projects, a tiller may be needed.
Hermaphrodite
: An individual having the reproductive organs
and many of the secondary sex characteristics of both
sexes.
HID
: High Intensity Discharge.
Hormone
: Chemical substance that controls the growth
and development of a plant. A substance produced by
one tissue and conveyed by the bloodstream to another
to effect physiological activity or regulate development,
such as growth or metabolism. Acts as a signal.
Humus
: The end result of successful composting
is humus. It is the rich, dark, and fine mixture of
decomposed organic materials. Humus contains the microorganisms
necessary for healthy soil, as well as a ready supply
of the macro- and micro-nutrients necessary for healthy
plants. It also helps create ideal soil tilth through
water retention and particle spacing. Use humus in
the garden to condition and amend soil. Mix it with
the soil for general improvement or use it to side-dress
hungry plants.
Hybrid
: An offspring created by combining two plants
of different breeds, variety, or genetic makeup.
Hydrogen
bond : A chemical bond in which a hydrogen
atom of one molecule is attracted to an electronegative
atom, especially a nitrogen, oxygen, or flourine atom,
usually of another molecule.
Hygrometer
: Instrument used to measure the relative
humidity in the atmosphere.
Hyphae
: A single tubular filament of a fungus or
any of the thread like parts making up the mycelium
of a fungus.
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I
Imbibition
: Imbibition will trigger a seed to germinate.
It is the absorption of water by the seed, which causes
its tissues to swell and for the seed's casing to
eventually split. Once the seed has split open the
radicle can begin its search of anchorage, water,
and nutrients.
Indeterminate
growth : Having a capacity for continuing
to grow at the apex.
Indigenous
: Existing or growing naturally in a region
or country.
Inductive
reasoning : Reasoning from detailed facts
to general principles. Opposite of deductive reasoning.
Inoculate
: To bring one organism or material into
contact with a host plant or plant organ or t o put
or implant microorganisms or anything beneficial to
plant growth into soil to stimulate growth, fix nitrogen,
etc.
Integrated
Pest Management (IPM): IPM is an ecologically
based approach to pest (animal and weed) control that
utilizes a multi-disciplinary knowledge of crop/pest
relationships, establishment of acceptable economic
thresholds for pest populations and constant field
monitoring for potential problems. Management may
include such practices as the use of resistant varieties;
crop rotation; cultural practices; optimal use of
biological control organisms; certified seed; protective
seed treatments; disease-free transplants or rootstock;
timeliness of crop cultivation; improved timing of
pesticide applications; and removal or 'plow down'
of infested plant material.
IPM/NDR:
Foods sold with claims of reduced pesticide
use or use of integrated pest management (IPM), sometimes
certified as containing no detectable residues (NDR).
Ions
: Atoms that carry an electric charge, either
positive or negative. If an atom gains an electron
it takes on a negative charge. If the atom loses
an electron it takes on a positive charge. Ex. Table
salt = NaCl, dissolved in water is Na+ and Cl-, hence
ions. The same idea is applied to salts that break
out into relavent nutrient spectrums for plant growth
in synthetic fertilizers.
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K
Kelp
meal : Kelp meal is used as a dry organic
fertilizer. It is rich in micronutrients and plant
growth hormones. It is also an excellent source of
potassium, of which it is about 18%.
Kilowatt-hour
(KWH): a power demand of 1,000 watts for one hour.
Power company utility rates are typically expressed
in cents per kilowatt-hour.
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L
Larvae
: A young insect that hatches from the egg
and differs fundamentally in form from the adult.
A maggot, the larval stage of a fly, is a good example
of this difference.
Leaching
: T he process by which soluble materials in the
soil, such as salts, nutrients, pesticide chemicals
or contaminants, are washed into a lower layer of
soil or are dissolved and carried away by water.
Legumes:
Legumes are plants that can fix nitrogen
from the air to make nitrates. Nitrate is nitrogen
in a form available to plants. Legumes, through pinkish
colored nodules on their roots, form a mutually beneficial
relationship with soilborne bacteria. It the bacteria
who are able to perform the chemistry necessary for
nitrogen fixation; the plant pulls the nitrogen from
the air through stomata in its leaves and transfers
it to the bacteria via its phloem. In return, the
legume and the plants nearby are supplied with the
nitrates. However, if legumes are fed nitrogen (in
the form of fertilizer or manure), they will cease
to produce their own. Legumes are heavy feeders of
phosphorus, potassium, magnesium, and calcium; so
they (or the crops that follow) may need feeding if
the soil is deficient in these nutrients. Legumes
are used as green manures. Common examples are clover,
vetch, soybeans, peas, and alfalfa.
Lenticels
: Region of roots that permit gas exchange.
Equivalent to stomata in leaf.
Ligands
: An atom, ion, or function group that is
binded to one or more central atoms or ions. An ion,
a molecule, or a molecular group that binds to another
chemical entity to form a larger complex.
Light
reaction : The photosynthetic process in
which solar energy is harvested and transferred into
the chemical bonds of ATP; can occur only in light.
Lime
: When calcium carbonate is finely ground
it is called lime. Ground lime is readily dissolved
into the soil where it reduces soil acidity by releasing
calcium cations. Can also be used to combat maggots
in worm bins or compost piles.
Lipids
: Diverse class compounds, including fats,
oils, fatty acids, triglycerides and steroids essential
for membrane formation, energy stores, and fuel molecules.
Loam
: Loam soils are comprised of sand, silt,
and clay particles. There are both coarse and fine
loams. Fine loams have more silt and clay than sand.
Coarse loams are mainly sand, which facilitates better
drainage, but still contain enough silt and clay to
hold moisture and nutrients and thereby support soil
organisms. For this reason, coarse loams are considered
some of the best soils to cultivate, with fine loams
not far behind
Local
Food Systems : A collaborative effort to
integrate agricultural production with food distribution
to enhance the economic, environmental, and social
well being of a particular place. This approach supports
a food system that preserves local farmland and fosters
community economic viability, requires less energy
for transportation, and offers consumers the freshest
foods.
Lumen
: A lumen is the unit that expresses the
total quantity of light given of by a source as seen
by the human eye, regardless of direction. A lumen
is defined as the amount of light falling on a surface
of one square foot, every point of which is one foot
away from a source, (a section of the inside surface
of a sphere) of one candlepower. A uniform source
of one candlepower placed in a sphere emits 12.57
lumens.
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M
Macronutrients
: Mineral elements required by plants in
large amounts- nitrogen, phosphorous, potassium, oxygen,
hydrogen, carbon, sulfur, magnesium, and calcium.
Malthus,
Thomas : " An Essay on the Principle of Population"
was first published in 1798. This important essay
first identified the geometric role of natural population
increase in outrunning subsistence food supplies,
prompting Charles Darwin to explore the actual patterns
of evolution. What "struck" Darwin in Essay
on the Principle of Population (1798) was Malthus's
observation that in nature plants and animals produce
far more offspring than can survive, and that Man
too is capable of overproducing if left unchecked.
Malthus concluded that unless family size was regulated,
man's misery of famine would become globally epidemic
and eventually consume Man. Malthus' view that poverty
and famine were natural outcomes of population growth
and food supply was not popular among social reformers
who believed that with proper social structures, all
ills of man could be eradicated. This sentiment is
similar to that of the Agricultural revolution in
that Nature could be manipulated with no dire repercussions.
Manure
: Nitrogen feeds the microorganisms in soil
that make humus from a compost pile. Manure is rich
in nitrogen (especially chicken, goat, and steer manures),
and is thus a valuable component of compost. It is
also rich in potassium and phosphorus. Manure should
be composted (or at least aged) before use in the
garden because of its high nitrogen --and ammonia--
content, which can both easily burn plants. Composting
will also kill any weed seeds that may have survived
the animal's stomach(s).
Meristem
: Group of undifferentiated cells from which
new tissues are produced, and one of the most basic
forms of plant tissue. Most plants have apical meristems
which give rise to the primary tissues of plants,
and some have secondary meristems that add wood or
bark. Similar to stem cells in animals. Meristem cells
can divide, whereas mature, differentiated cells are
specialized in structure and function and usually
do not divide. Continued divisions of meristem cells
keeps a plant growing throughout it's life = indeterminate
growth.
Metabolism
: The chemical processes occurring within
a living cell or organism that are necessary for the
maintenance of life. In metabolism some substances
are broken down to yield energy for vital processes
while other substances, necessary for life, are synthesized.
Micronutrients
: Elements which are required in very small
or trace amounts- iron, chlorine, copper, manganese,
zinc, molybdenum, and boron.
Microorganism
: An organism of microscopic or submicroscopic
size, especially a bacterium or protozoan.
Mineral
: A naturally occurring, homogeneous inorganic
solid substance having a definite chemical composition
and characteristic crystalline structure, color, and
hardness.
Mineralizaton
: Process carried out by soil microorganisms
whereby nutrients are released in an inorganic form
from the decomposition of organic matter.
Mitosis
: The process by which a cell divides into
two so that the nucleus of each new cell has a full
number of chromosomes.
Monocot
: One of the two major types of flowering
plants; characterized by having a single cotyledon,
arranged in threes or multiples of three, and parallel-veined
leaves; include grasses, cattails, lilies, and palm
trees.
Monoecious
: Plants that have both male and female flowers
on the same plant. Most plants of production have
been breed to be self-fertilizing or monoecious.
Mother
plant : A superior plant that is kept in
the vegetative state in order to take cuttings or
clones from. When a mother plant is found it is important
to ensure maximum success rate so as not to stress
the mother plant with too many cuttings.
Mucigel
: The gelatinous material at the surface
of roots grown in nonsterile soil. It includes natural
and modified plant exudates (more specifical | 
