Graan SA Jaarverslag 2019 New

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en die bedryf indringerplae en patogene se binnekoms in Suid-Afrika
moet identifiseer en bestuur, aangesien gewasverliese nasionale
voedselsekerheid bedreig.
Klimaatsaanpasbaarheid
Daar word toenemend voorspellings gemaak oor hoe klimaats-
toestande in die komende jare sal verander, maar hierdie voorspellings
sal betekenisloos wees as strategieë om by hierdie toestande aan te
pas, nie in plek is nie. Ten einde te verseker dat produsente – veral
kleinskaalse produsente – sal voortgaan om volhoubaar te wees, is
die Klimaataanpasbaarheidskonsortium (CRC) gestig. Navorsers van
Sensako, Rhodes Universiteit (RU) en Universiteit Stellenbosch (US)
werk saam om klimaataanpasbare mielielyne met meer voedingswaarde
en beter siekteweerstandigheid te teel.
Hierdie lyne word dan by die ultramoderne verhoogde-CO2-fasiliteit by
die RU aan die hand van voorspelde toekomstige toestande geëvalueer.
Gedurende die afgelope jaar is daar ’n paar opwindende treë vorentoe
gegee toe koring ook bygevoeg is (onder leierskap van die Universiteit
van Fort Hare). Dit word tans by die RU geëvalueer. Studies oor die kort-
tot mediumtermynuitwerking van klimaatsverandering en aanpassings
word ook deur navorsers by die Universiteit van Kaapstad gedoen.
UITBREIDING VAN MIELIES SE GENETIESE
VERANDERLIKHEID VIR HITTE EN DROOGTE
Nuwe mieliekiemplasma met materiaal van die LNR en CIMMYT word
tans gebruik om die hitte- en droogteverdraagsaamheid van Suid-
Afrikaanse kultivars te verhoog. Die grootte van die telingsprogram word
uitgebrei om groter keuringsintensiteit moontlik te maak, te verseker dat
daar voldoende genetiese verandering is, die akkuraatheid van seleksie
te verhoog, en instrumente vir die ondersteuning van besluitneming te
verbeter. Die klem van hierdie telingsprogram is om materiaal te verskaf
wat vir kleinskaalse produsente nuttig sal wees, hoewel die materiaal tot
alle produsente in Suider-Afrika se beskikking sal wees.
MIELIES EN KORING SE REAKSIE OP DROOGTE ONDER
TOEKOMSTIGE KLIMAATSTOESTANDE
Die verhoogde-CO2-fasiliteit by die RU maak dit moontlik om gewasse
onder toekomstige klimaatstoestande, met ander woorde verhoogde
CO2 en hoër temperature, te toets. Tot dusver lyk dit asof verhoogde
CO2 mielies se droogteverdraagsaamheid verhoog, maar dit verlaag die
opbrengs en voedingswaarde. Koringgenotipes word tans geëvalueer.
Klimaataanpasbare lyne wat tot dusver geteel is, sal in die toekoms by
hierdie fasiliteit getoets word om seker te maak dat gewasse voorspelde
klimaatstoestande kan weerstaan.
KLIMAATSRISIKO
Klimaatsrisiko word omskryf as die risiko voortspruitend uit klimaatsver-
andering en wat natuurlike en menslike stelsels en streke aantas.
Produsente kan hierdie risiko’s bestuur deur ingeligte besluite oor
gewaskeuse, plantdatums, bemestingsbehandeling en siektebestuur-
strategieë te neem. Die bestuur van klimaatsrisiko’s verg egter ’n deeg-
like begrip van ’n produsent se spesifieke boerderypraktyke en die
streek se klimaatstoestande. Ten einde nuttige inligting te produseer
oor klimaatsrisiko’s en hoe om dit te bestuur, is belanghebberinteraksie
noodsaaklik. ’n Projek is tans aan die gang om klimaatsrisiko’s vir belang-
rike (en miskende) mielieproduksiegebiede van Suid-Afrika te evalueer.
VENSTER VIR MIELIE-AANPLANTINGS
Reënvalpatrone sal na verwagting beduidend deur klimaatsveran-
dering geraak word, en daar word voorspel dat dit tot ’n afname in die
getal reëndae en langer droë tye sal lei. Hierdie verskynsel is in die
2018/2019-seisoen algemeen in Suid-Afrika waargeneem, aangesien
die gebrek aan reën tydens optimale plantvensters plantdatums
vertraag het – tot op die punt waar heelwat van die aanplantings buite
die normale plantvensters plaasgevind het. Die Graannavorsing- en
Beleidsentrumspan is tans besig om ’n projek te loods om die impak van
laat aanplanting van mieliekultivars te ondersoek – veral ten opsigte van
opbrengs, gehalte en fisiologiese reaksies.
Climate resilience
Predictions of how climatic conditions will change in the coming years
is becoming increasingly available; however, these predictions will
be meaningless if strategies to adapt to these conditions are not in
place. In order to ensure that producers will continue to be sustainable,
specifically smallholder producers, the Climate Resilience Consortium
(CRC) was founded. Researchers from Sensako, Rhodes University
(RU) and Stellenbosch University (SU) are collaborating to breed climate
resilient maize lines with increased nutritional value and improved
disease resistance.
These lines will then be evaluated under predicted future conditions
at the state-of-the-art elevated CO2 facility at RU. The past year has
seen some exciting strides forward in this consortium as wheat was
also added (under the leadership of the University of Fort Hare) and is
currently being evaluated at RU. Furthermore, studies concerning the
short to medium term effects of climate change and adaptations are
also being conducted by researchers from the University of Cape Town.
EXPANDING MAIZE GENETIC VARIABILITY
FOR HEAT AND DROUGHT
New maize germplasm using material from the ARC and CIMMYT is
currently being used to increase heat and drought tolerance of South
African cultivars. The size of the breeding programme is being increased
to enable higher selection intensity, ensure adequate genetic variation,
increase accuracy of selection, accelerate breeding cycles and improve
decision support tools. The emphasis of this breeding programme is to
deliver material which will be useful to smallholder producers, although
the material will be available to all producers in Southern Africa.
MAIZE AND WHEAT DROUGHT RESPONSE UNDER
FUTURE CLIMATIC CONDITIONS
The elevated CO2 facility at RU enables testing of crops under future
climatic conditions – i.e. increased CO2 and increased temperatures.
Thus far it seems that elevated CO2 increases maize drought
tolerance, however, this comes at a cost to yield and nutritional value.
Wheat genotypes are currently being evaluated. In future, climate
resilient lines bred thus far will be tested at this facility to ensure
crops can withstand predicted climatic conditions.
CLIMATE RISK
Climate risk is defined as the risk resulting from climate change and
affecting natural and human systems and regions. Producers can man-
age these risks by making informed decisions regarding crop choice,
planting date, fertiliser application and disease management strategies.
However, to manage climate risks require a sound understanding of a
producer’s specific farming practices and the region’s climatic condi-
tions. In order to produce useful information regarding climate risks and
how to manage them, stakeholder interaction is essential. A project is
currently being conducted to assess climate risks for important (and
overlooked) maize production regions in South Africa.
MAIZE PLANTING WINDOW
Rainfall patterns is expected to be significantly impacted by climate
change and is predicted to lead to decreases in the number of
rainy days and increased duration of dry spells. This phenomenon
was widely observed in South Africa during the 2018/2019 season,
as lack of rainfall during optimal planting windows led to delayed
planting dates; to the point where much of the planting took place
beyond normal planting windows. The Grain SA Research and Policy
Centre team launched a project to investigate the impact of late
planting of maize cultivars, specifically addressing yield, quality and
physiological responses.