SA Graan Julie 2015

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PANNAR se ongeëwenaarde graansorghum-pakket
vorm die ruggraat van graansorghum-produksie in
Suid-Afrika. Plaaslik-ontwikkelde basters word ook
in Suid-Amerika, Meksiko, Australië en die res van
Afrika aangeplant.
Bio-etanol-produksie
gerugsteun
deur wêreldklas-
navorsing.
2015/GSS/A/17
® Geregistreerde handelsmerke van PANNAR BPK, © 2014 PANNAR BPK
Saam boer ons
vir die toekoms™
ULTRAMODERNE
NAVORSING
GEWASVOORSORG PRESISIE-
BEPLANNING
GEWASBESKERMINGS-
BESTUURSPRAKTYKE
Management challenges
Many reports have shown that mole crickets can cause serious
damage to bahiagrass pastures. Bahiagrass is also susceptible to
“dollar spot“ (Sclerotinia homoeocarpa) and “ergot“ (Claviceps
paspali) diseases in hot, damp weather conditions. These diseases
will affect seed and production yield, but in general, none of these
diseases are toxic or a problem to livestock.
Animal production aspects
The energy concentration of bahiagrass – which is reflected in the
digestibility of the herbage – declines considerably as the season
progresses, irrespective of how fertile the soil is or the way it is de-
foliated. Various studies show that well-fertilised bahiagrass remains
at 10% to 12% crude protein (CP).
As a result, bahiagrass is not well-suited to support the demands
of livestock with high nutritional requirements, such as growing
animals or lactating dairy cows. Concentrations for phosphorus (P)
in leaf tissue may range from 0,10% to 0,45%, and for potassium
(K), it may range from 1,1% to 2,5%. The addition of fertiliser will
be necessary to maintain adequate dry matter production, if the
leaf concentrations of phosphorus drop below 0,10%, or 1,1% for
potassium.
Average daily gains (ADG; kilograms of live weight gained per day)
of bahiagrass are usually lower than other subtropical perennial
grasses. Studies on continuously grazed (continuous stocking) ba-
hiagrass pastures have ADG of heifers ranging from 150 g/day to
550 g/day.
However, these numbers generally decline from summer to autumn.
The ADG in summer will often range from 550 g/day to 600 g/day in
January/February. When pastures are under-stocked in the summer,
daily gains are usually low, associated with over-mature growth.
Conclusion
Bahiagrass is a species well-known for its adaptation to very wet
and acidic soils and has the secondary purpose of mopping up
some of the excess P should this be the case. This is especially ap-
plicable where soils have received numerous amounts of animal
manure over the years.
If a species is to be recommended to be planted on grain crop
soils that are grown under irrigation in areas that are relatively cool,
this species will have the ability to improve these intensively man-
aged soil conditions if used as a pasture ley crop.
For more information, contact Dr Wayne Truter at wayne.
Prof Chris Dannhauser at
Dr Hendrik Smith at or Mr Gerrie
Trytsman at
References
Dickinson, E.B., Hyam, G.F.S., Breytenbach, W.A.S., Metcalf, W.D., Basson, W.D.,
Williams, F.R., Scheepers, L.J., Plint, A.P., Smith, H.R.H., Smith, P.J., van Vuuren,
P.J., Viljoen, J.H., Archibald, K.P. and Els, J.N. 2004. Kynoch pasture handbook .
Kejafa Knowledge Works, Maanhaarrand.
Newman, Y., Vendramini, J. and Blount, A. 2014. Bahiagrass (Paspalum notatum):
Overview and management.
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CONSERVATION AGRICULTURE