incidence

of


increasing

disease


pressure


of


the


plant


and

the


Aeroponic


system.
Other

benefits


of


air

(CO2
Plants

in


a

true


Aeroponic


apparatus


have

100%

access

to


the


concentrations


ranging


from

450

ppm


to


780
ppm

for


photosynthesis.



At


one

mile


(1.6


km)


above


sea

level

the


CO2s

concentration


in


the


air

is


450

ppm
during

daylight.


At


night


the


CO2s

level

will


rise

to


780

ppm.


Lower


elevations


will


have

higher


levels.


In
any
case,


the


air

culture


apparatus


offers


ability

for


plants

to


have

full


access

to


all


the


available


CO2s

in


the
air
for


photosynthesis.


Growing


under

lights


during


the


evening


allows


Aeroponics


to


benefit


from

the


natural
occurrence.
Disease
-

free


cultivation
Aeroponics

can

limit


disease


transmission

since


plant

-

to

-

plant


contact


is


reduced

and

each

spray


pulse


can
be
sterile.


In


the


case

of


soil,


aggregate,


or


other


media,


disease


can

spread

throughout


the


growth


media,
infecting

many


plants.


In


most


greenhouses


these


solid

media


require

sterilization


after


each

crop


and,


in
many

cases

they


are


simply


discarded


and

replaced


with


fresh,


sterile

media.


A

distinct


advantage

of
Aeroponic

technology


is


that


if

a

particular

plant


does

become

diseased,


it

can

be

quickly

removed


from

the
plant

support


structure


without


disrupting


or


infecting


the


other


plants.
Due

to


the


disease

-

free


environment


that


is


unique


to


Aeroponics,


many


plants

can

grow

at


higher


density
(plants

per


sq

meter)


when


compared


to


more


traditional


forms

of


cultivation


hydroponics,


soil


and

Nutrient
Film

Technique

[NFT]).


Commercial


Aeroponic


systems


incorporate


hardware

features

that


accommodate


the
crops

expanding

root


systems.


Researchers

have

described


Aeroponics


as

a

"valuable,


simple,


and

rapid
method

for


preliminary


screening


of


genotypes

for


resistance

to


specific


seedling


blight


or


root


rot.”


The
isolating
nature


of


the


Aeroponic


system

allowed


them

to


avoid


the


complications

encountered

when


studying
these

infections


in


soil


culture.
Water

and


nutrient


hydro

-

atomization
Aeroponic

equipment


involves

the


use

of


sprayers,


misters,

foggers,


or


other


devices


to


create


a

fine

mist


of
solution

to


deliver


nutrients


to


plant


roots.


Aeroponic


systems

are


normally


closed

-

looped


systems


providing
macro

and

micro

-

environments


suitable


to


sustain

a

reliable,


constant


air

culture.


Numerous

inventions


have
been

developed

to


facilitate

Aeroponic


spraying


and

misting.


The


key

to


root


development


in


an

Aeroponic
environment

is


the


size


of


the


water


droplet.


In


commercial


applications,

a

hydro

-

atomizing


spray


at


360°


is
employed

to


cover


large


areas


of


roots


utilizing


air

pressure


misting.
A
variation


of


the


mist


technique


employs


the


use

of


ultrasonic


foggers


to


mist


nutrient


solutions


in


low

-
pressure

Aeroponic


devices.


Water


droplet

size


is


crucial


for


sustaining


Aeroponic


growth.


Too


large


a

water
droplet
means


less


oxygen


is


available


to


the


root


system.


Too


fine

a

water


droplet,


such

as

those


generated
by
the


ultrasonic


mister,

produce

excessive


root


hair


without


developing


a

lateral


root


system

for


sustained
growth

in


an

Aeroponic


system.


Mineralization

of


the


ultrasonic


transducers


requires

maintenance


and
potential

for


component


failure.


This


is


also


a

shortcoming


of


metal


spray


jets

and

misters.

Restricted


access
to

the


water


causes

the


plant


to


lose


turgidity


and

wilt.
Advanced

materials