Bulletin 25 2010 - BSES

6
QCrOps / BArry sALTer
[It is clear from all the trials that current varieties
are suitable for different row configurations. No variety-by-row
configuration interaction was found in any trial.]
TABlE 6 | Cane (TCH) and sugar (TSH) yield of varieties Q186 A , Q200 A , Q201 A and Q220 A grown on 1.52 m single, 1.85 m
single and 1.85 m dual rows at Meringa.
Meringa
crop
AVERAGES fOllOWED BY THE SAME lETTER ARE NOT SIGNIfICANTlY DIffERENT
At Meringa (Table 6) a significant row
configuration effect was found in the
1st ratoon crop. Significantly less cane
(TCH) was produced on the 1.85 m single
row configuration by comparison with
the 1.52 m single and 1.85 m dual row
configurations. Although not significant,
there was also a strong trend for lower
sugar yield in the 1st ratoon crop on the
1.85 m single row configuration.
Q200 A and Q220 A performed well at this
site but again there was no significant
variety-by-row spacing interaction. As
explained previously, this means that the
varieties all responded to the different row
configurations in a similar manner.
DisCussiON
Yield
It is clear from all the trials that current
varieties are suitable for different row
configurations. No variety-by-row
configuration interaction was found
in any trial. This suggests that if you
select a variety that performs well at a
particular site, it will perform well on all
row configurations. It also indicates that
varieties that perform well on wide-row
configurations are making it through the
breeding program (and will continue to
do so).
Row configuration
Plant TCH 1.52 m single
1.85 m single
1.85 m dual
Mean
TSH
1.52 m single
1.85 m single
1.85 m dual
Mean
1st Ratoon TCH 1.52 m single
1.85 m single
1.85 m dual
Mean
TSH
1.52 m single
1.85 m single
1.85 m dual
Mean
Q186A 103.0
91.4
101.4
98.6a 16.5
14.4
15.6
15.5 a
104.0
95.1
105.1
101.4 a
18.9
16.9
19.1
18.3 a
Q200A 115.7
114.8
119.3
116.6bc 18.9
18.0
19.2
18.7 bc
116.8
105.1
117.2
113.0 b
21.1
19.3
21.8
20.7 b
In two trials (Mackay and Meringa)
the wide single-row configuration
produced significantly lower yields than
the narrow single and wide dual-row
configurations. This is most likely related
to the environmental conditions at each
site. Trials that had access to irrigation
(Bundaberg and Burdekin) did not show
any loss of yield on the wide single-row
configuration. Even though irrigation
was available at Mackay, the soil surface
sealed and water was shed from the
beds, resulting in very dry soil conditions
during establishment. It appears that if any
significant stress (drought, waterlogging,
etc.) is encountered, the wide single-row
configuration can produce too few stalks to
reach maximum yield. Environmental stress
can also prevent the stalks that are present
from increasing in size to compensate for
low numbers.
Planting rates on the wide single-row
configuration may also be too low and
contributing to this issue, particularly in
trials where billets are often placed endto-end
due to limited planting material.
Growers planting wide single rows with
billet planters and higher planting rates
don’t appear to be suffering this yield loss.
Variety
Q201A 112.3
100.2
115.6
109.3b 17.7
15.6
18.1
17.1 b
110.3
91.5
102.2
101.4 a
19.2
16.1
17.4
17.6 a
Q220A 123.6
121.0
126.5
123.7c 19.5
19.2
19.7
19.5 c
131.4
117.8
132.6
127.3 c
23.0
20.7
23.6
22.4 b
Mean
113.7 a
106.8 a
115.7 a
18.1 a
16.8 a
18.2 a
115.6 b
102.4 a
114.3 b
20.6 a
18.2 a
20.5 a
Average cane yields for both the narrow
and wide single-row configurations were
118.8 and 112.6 t/ha, respectively (showing
an average 5% reduction in yield on the
wide single-row configuration). If this
reduction was experienced in commercial
crops, it would have to be assessed against
the positive attributes of a controlled-traffic
farming system.
The variety effects found in these trials are
likely to be site-specific. As an example,
the poor performance of Q183 A at the site
near Ingham may just indicate that it was
not suited to that particular soil type rather
than indicating that Q183 A will not perform
well in the Ingham region in general. This
should be kept in mind when assessing the
performance of the varieties at each site.
*BSS296 – Evaluation of genotypes for
a controlled-traffic farming system is
funded by SRDC.