44. Volume 15- Number 2 - IP Australia

DESCRIPTIONS
PLANT VARIETIES JOURNAL 2002 VOL 15 NO. 2
HAIR GROUP 57 – OCCURRENCE
medium sparse to medium to
medium dense
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HAIR GROUP 57 – LENGTH
medium short medium to long
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LIGULE HEIGHT
medium wide medium
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HAIR GROUP 61 – DENSITY/ OCCURRENCE
dense medium medium
to dense to dense
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AURICLE -PROMINENCE (Second Fully Unfurled Leaf)
medium inconspicuous prominent
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AURICLE SHAPE – ULP
calcariform lanceolate lanceolate
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AURICLE SHAPE – OLP
lanceolate transitional transitional
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AURICLE SIZE – ULP
small to very small medium to
medium to small large
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Means followed by the same letter are not significantly different at
P≤0.01, Duncan’s Multiple Range Test.
‘Q197’
Application No: 2002/026 Accepted: 4 Mar 2002.
Applicant: Bureau of Sugar Experiment Stations,
Indooroopilly, QLD.
Characteristics (Table 37, Figure 44) Ploidy: cytologically
complex polyploid and aneuploid interspecific hybrid.
Plant: stool growth habit erect, tillering medium, number of
suckers very few, leaf canopy light to medium. Stem: culm
height (base to TVD leaf) tall to very tall with mean length
approximately 2.53m (range 1.96 to 3.21m). Internode:
length on bud side medium to long with mean length
approximately 14.1cm (range 10.4 to 18.6cm), length on
opposite to bud side medium to long with mean length
approximately 13.7cm (range 9.7 to 18.2cm), diameter of
longest internode central and perpendicular to bud thick
with mean approximately 26.2mm (range 21.4 to 30.7mm),
diameter of longest internode central and dissecting bud
thick with mean approximately 26.7mm (range 21.9 to
31.9mm), shape cylindrical to bobbin, cross-section round,
colour of dewaxed internode exposed to sun brown RHS
200D to greyed-brown RHS 199A, unexposed colour
yellow-green RHS 153D, waxiness light, wax band
moderate to distinct and width narrow to medium,
expression of zigzag alignment strong, growth cracks few,
cork cracks very few to few. Bud groove: prominence
medium, length short to long, depth shallow. Node: width of
root band on bud side medium to wide (mean 10.6mm), bud
prominence medium, bud shape triangular pointed with
position of base near to leaf scar, bud tip in relation to
growth ring level, bud width excluding wings very narrow
to narrow, bud wing width narrow to medium, leaf scar
medium prominence and oblique descending towards bud,
growth ring flush. Leaf: lamina length of TVD leaf very
short to short with mean approximately 1.33m (range 1.15
to 1.56m), width medium to wide with mean approximately
45.4mm (range 34.9 to 50.7mm) at longitudinal midpoint
and curved near tip in attitude, midrib width of lamina at
longitudinal midpoint narrow to medium with mean 3.7mm
(range 2.9 to 4.9mm), ratio of lamina width/midrib width
medium with mean approximately 12.7 (range 7.3 to 16.0).
Leaf sheath: length of leaf sheath of TVD leaf short to
medium with mean approximately 33.6cm (range 24.5 to
37.0cm), adherence of sheaths of senescent leaves to culm
medium, density of hairs on abaxial leaf sheath surface
(Group 57) sparse to medium and length short to medium.
Ligule: shape crescentiform, width at midrib section
medium to wide, density of cilia along the free margin of
ligule (Group 61) dense and length very short. Auricles:
prominence medium, symmetrical, shape lanceolate, size
small to medium. Inflorescence: open panicle. Flowering:
discontinuous. Seed or fruit: caryopsis. Disease resistance:
very highly resistant to Fiji Disease Virus, highly resistant
to Leaf Scald (Xanthomonas albilineans (Ashby) Dowson),
highly susceptible to Red Rot (Glomerella tucumanensis
(Spego) Arx and Mueller), and resistant to Pachymetra Root
Rot. Other characteristics: fibre quantity and quality are
acceptable for milling purposes (impact reading 0.43, shear
strength 27.5, short fibre 56.4%). In addition, ‘Q197’ was
uniquely identified by DNA fingerprinting using
microsatellite markers, and did not match any other current
sugarcane DNA profile.
Origin and Breeding Controlled pollination: seed parent
‘58N829’ x pollen parent ‘66N2008’ in a planned breeding
program at Meringa (Gordonvale), QLD. ‘Q197’ is very
highly resistant to Fiji Disease Virus (score 1) and resistant
to Pachymetra Root Rot (score 3), while ‘58N829’ is
susceptible to Fiji Disease Virus (score 7) and ‘66N2008’ is
intermediate to susceptible to Pachymetra Root Rot (score
6). ‘Q197’ has been evaluated and selected by BSES in
yield trials on the Central Sugar Experiment Station at
Mackay and sites within the sugarcane growing area in the
Central region. Standard commercial varieties were also
included in the trials for comparative purposes. Selection
criteria: cane yield, ccs, and sugar yield have been the main
selection criteria. Disease resistance screening was
conducted at the pathology farm (Eight Mile Plains) and in
the Tully glasshouse. Propagation: after an initial seedling
stage (using seed from the cross), all subsequent stages have
involved vegetative propagation. Breeder: Bureau of Sugar
Experiment Stations. QLD.
Choice of Comparators ‘Q96’ and ‘Q124’ were chosen, as
they are the most similar varieties grown in the Central
region. ‘Q96’ accounted for about 0.7% (57,000 t), while
‘Q124’ accounted for 65.6% (5.0 million t) of the Central
region crop in 2001. Neither parent was included as a
comparator as both have been discarded from the parent
collection. However, the parents could be distinguished
from the candidate variety by their individual disease
resistance scores as mentioned above.
Comparative Trial Location: conducted at Central Sugar
Experiment Station (21º 9′ South, 149º 7′ East), Te Kowai,
QLD. The trial was planted 20 Sep 2000, harvested on 5 Oct
2001 and ratooned. DUS data were recorded end of May
2001. Conditions: clones were propagated from vegetative
cuttings and grown under field conditions. Soil type:
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