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September 2018
the previous ten-year crop average
(11 096 476 tons). White maize’s contri
bution to the total production was
9 916 000 tons (59%) and that of yellow
maize 6 904 000 tons (41%).
The total area utilised for maize production
in the 2016/2017 season was 2 628 600 ha,
an increase of 35% compared to the pre
vious season and 2,4% higher than the pre-
vious ten-year average. White maize was
planted on 1 643 100 ha and yellow maize
on 985 500 ha (1 014 750 and 932 000 ha
respectively in the 2015/2016 season).
Maize yield also reached an all-time
high of 6,40 t/ha this season compared
to the 4 t/ha in the previous season and a
4,31 t/ha ten-year average. White maize
yielded 6,03 t/ha and yellow maize 7,01 t/ha.
Due to the record local crop no maize where
imported during the period May 2017 to
April 2018.
Grading
1 000 composite maize crop samples,
representing individual silo bins and bun-
kers, were received this season. The maize
crop was of very good quality, with 85%
of white and 92% of yellow maize, graded
as maize grade one, compared to the 72%
and 78% of the 2015/2016 season. The
percentage total defective kernels above
and below the 6,35 mm sieve, 4,7% for
white and 4,4% for yellow maize, was 1,5%
and 1,3% respectively lower than the previ-
ous season.
The percentages Diplodia as well as
Fusarium infected kernels on both white
and yellow maize were between 0,2% and
0,4% lower than in the previous season.
Foreign matter did not pose significant
problems, with seven white and three yel-
low maize samples downgraded to class
other maize due to foreign matter exceed-
ing 0,75%. Only one yellow maize sam-
ple was downgraded as a result of other
colour maize that exceeded 5%. The aver-
age percentage combined deviations of
white maize was 5,1% compared to the
6,7% of the 2015/2016 season, that of yellow
maize was slightly lower, 4,7% compared
to 6% previously.
Physical quality factors
Test weight is determined at most intake
points locally. White maize had an average
test weight of 77,7 kg/hl compared to the
76,9 kg/hl of yellow maize. White maize’s
average test weight was 0,3 kg/hl lower
than the previous season and that of yellow
maize 0,2 kg/hl higher. The test weight in
total varied from 67,6 kg/hl to 82,4 kg/hl.
Graph 1: Deoxynivalenol occurrence in the 2016/2017 maize crop.
Graph 2: Deoxynivalenol occurrence in the 2016/2017 white maize crop.
Graph 3: Deoxynivalenol occurrence in the 2016/2017 yellow maize crop.