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Abnormale lae temperature vroeg in Junie het veroorsaak dat plante
onder geweldige stres verkeer het en gevolglik het die patogeniese
effek van die virus na vore getree.
Die vraag is nou hoekom net die een spesifieke kultivar? Die antwoord
hierin lê waarskynlik in die geweldige aggressiewe saailinggroeikrag
van hierdie kultivar. Verskeie van die produsente het genoem dat
hierdie kultivar baie vinniger as hulle ander kanola ontwikkel het
en dat dit waarskynlik die mooiste kanola was wat hulle tot nog toe
gehad het.
Hierin opgesluit lê waarskynlik ‘n groot deel van die rede hoekom
die spesifieke kultivar uitgesonder is. As gevolg van die vinnige
Beet Western Yellow virus
vanjaar opgemerk
ontwikkeling was die saadbehandeling nie meer effektief nie en die
vermoede bestaan dat hierdie kultivar net soveel meer aanlokliker
was vir die groenperskeluis. Latere aanplantings het nie die virus-
effek getoon nie, waarskynlik omdat die saadbehandeling nog effek-
tief was.
Agricol is tans besig om metodes te ondersoek om die risiko van
verdere uitbrekings in die toekoms te beperk en sal binnekort voor-
stelle maak en inligting beskikbaarstel. Fokus sal hoofsaaklik wees
op die beheer van die vektore wat die virus oordra. Veral met die
fokus op die groenperskeluis wat blyk om die belangrikste vektor te
wees. Produsente is welkom om Agricol te kontak met enige verdere
navrae.
39
September 2015
Plant-strengthening agent enhances
natural ability of plants to survive
D
rought, diseases and fungi: These are factors that pro-
ducers have no control over and they often have to watch
despondently as their crops are damaged. In addition, the
practice of breeding plants in special and strictly controlled
conditions has resulted in crops losing the chemical ability to protect
themselves in nature.
Researchers at the Department of Soil, Crop, and Climate Sciences
of the University of the Free State (UFS) have developed an organic
agent that restores this chemical imbalance in plants. It enables the
plant to build its own resistance against mild stress factors and thus
ensures increased growth and yield by the plant.
ComCat
®
, a plant-strengthening agent, is the result of extensive re-
search by the German company, Agraforum AG, together with the
UFS. Commercialisation was initially limited to Europe, while re-
search was done at the UFS.
“Plants have become weak because they were grown specially
and in isolation. They can’t protect themselves any longer,” says
Dr Elmarie van der Watt from the department.
Dr Van der Watt says that, in nature, plants communicate by means
of natural chemicals as part of their resistance mechanisms towards
various stress conditions. These chemicals enable them to protect
themselves against stress conditions, such as diseases and fungi
(biotic conditions) or wind and droughts (abiotic conditions).
Most wild plant varieties are usually well-adapted to resist these
stress factors. However, monoculture crops have lost this ability to
a large extent.
The European researchers extracted these self-protection chemicals
from wild plants, and made them available to the UFS for research
and development.
“This important survival mechanism became dormant in monocul-
ture crops. ComCat essentially wakes the plant up and says ‘Hey, you
should start protecting yourself.’”
Research over the last few years has shown that the agent, applied
mostly as a foliar spray, subsequently leads to better seedlings, as
well as to growth, and it yields the enhancement of various crops.
This is good news for the agricultural sector as it does not induce un-
wanted early vegetative growth that could jeopardise the final yield
– as has happened in the past for nitrogen application at an early
growth stage.
“The use of synthetic agents, such as fungicides which contain cop-
per, are now banned. Nowadays, options for natural and organic
agriculture are being investigated. This product is already wide-
ly used in Europe, but because producers are often swamped by
quacks, the South African market is still somewhat sceptical.”
“
ComCat essentially wakes
the plant up and says
‘Hey, you should start
protecting yourself.’
“
LACEA LOADER,
director: Communication and Brand Management, University of the Free State
FOCUS
Special
Integrated pest control