Handbook for Irrigation of Wine Grapes in South Africa

Abbreviations, acronyms and symbols

OH -

: hydroxyl

OHS

: open hydroponic system

‰

: per 1000

p P

: probability value

: phosphorus

PAW

: plant available water

Pb pH PO

: lead

: negative logarithm of hydrogen ion activity

: phosphate

4

PRD

: partial root zone drying : precipitation threshold

P threshold

Ψ Ψ Ψ Ψ

: water potential

: leaf water potential

L

: soil water matric potential

m

: osmotic potential

o

Ψ PD

: predawn leaf water potential

Ψ S

: stem water potential : polyvinyl chloride : permanent wilting point : electrical resistance : readily available water

PVC PWP

R

RAW

ρ S

: bulk density

b

: sulphur

SABS

: South Africa Bureau of Standards

SAR

: sodium adsorption ratio

SAWS

: South African Weather Service

SWC TDS

: soil water content : total dissolved salts : total titratable acidity

TTA

ϴ ϴ V. vs

: gravimetric soil water content : volumetric soil water content

m

v

: vitis

: versus

VA

: volatile acidity

VINET

: VINeyard EvapoTranspiration

viz

: videlicet

VPD VSP WFD WUE

: vapour pressure deficit : vertical shoot positioning : wetting front detector

: water use efficiency

WUE GM

: gross margin water use efficiency

Zn

: zinc

IRRIGATION OF WINE GRAPES 309