South African Avocado Growers’ Association
2020 Yearbook
Volume 43
Table of Contents
S Magagula
HORTICULTURE
6
Observations on the effects that row 
orientation, ridging and orchard altitude have on avocado production in the 
Tzaneen area
FJ Kruger, GO Volschenk and LC Volschenk
11 Water use of avocado orchards – Year 3
E Mazhawu, AD Clulow, MJ Savage and NJ Taylor
18
Research towards reducing the incidence of 
lenticel damage of South African ‘Hass’ export avocado fruit
D Lemmer and JF Fourie
52
Concise overview of microbes related to soil 
health
JJ Bezuidenhout
PATHOLOGY
58
Investigating phosphonic acid residues in 
late hanging fruit and in tree roots from trees that received one versus two 
annual trunk injections
A McLeod, P Novela, P Mohale and S Masikane
64
Cercospora spot of avocado – Validation of 
spray timing: Final results
MH Schoeman and R Kallideen
POSTHARVEST
70
Preharvest application elicitors as an 
alternative to prochloraz
M Thema, H Fotouo-M. and D Sivakumar
76
Comparison of the ripening inhibitory effects 
of controlled atmosphere and balanced atmosphere on South African ‘Hass’, 
‘Maluma’ and ‘Fuerte’ avocado fruit under laboratory conditions during the 2019 
season
FJ Kruger, GO Volschenk and L Volschenk
80
Determining how effective a dry ice 
based modified atmosphere treatment will be at suppressing avocado respiration 
in packhouse cold rooms and refrigerated trucks
FJ Kruger, GO Volschenk and L Volschenk
88
Effects of cultivar, season and altitude 
on South African avocado fruit’s soluble solid contents and early season quality
FJ Kruger, GO Volschenk and LC Volschenk
92
Maturity indexing and storage protocols 
for ‘Lamb Hass’ and ‘Reed’ avocado cultivars
LS Magwaza, E Cekwane, A Mditshwa and SZ Tesfay
106 The impact of farm-to-packing facility road condition on avocado quality