D. Kenefick and J. Koepke.
Reduced-height winter-hardy mutants of HRWW.
In 1989, the SDAES registered 29 reduced-height mutant-derived
(MD) germplasm lines, obtained by treating 1,000 `Winoka'
seeds with azide. These lines were selected in the greenhouse
from three M1 plants with substantially reduced height compared
to Winoka. Greenhouse M2 seed resulted in plants numbered from
8001 to 8176, 16001 to 16225, and 17001 to 17115. Selection criteria
for M3 plants were seed yield/plant and short stature. M4 seed
of the MD germplasm was increased at Stillwater, OK, after which
field testing continued in SD. During 1985, field results showed
average M5 plant heights were 76.6 cm for the 8,000 selected lines,
60.2 cm for the 16,000, and 63.7 cm for the 17,000, compared to
Winoka at 78 cm. In 1987, 25 M5 germplasm lines were planted
in two replications at Northern Regional Winter hardiness Nursery
sites. Differential winter survival was observed only at Casselton,
ND. Three MD germplasm lines, SDM8127, SDM16050, and SDM16029,
had survivals of 82, 83, and 75 %, respectively, compared to Winoka
at 35 % (Table 1).
Correlation of Casselton freeze survival data with
leaf 4 osmotic potential of SDM8127 plants and those from 16,000
SDM germplasm lines was r = 0.94 after treating plants at 2_C
for 5 wk (Table 1). Differences among the SDM germplasms included
winter hardiness, leaf osmotic potential, seed yield, head density,
and leaf color. Seed of 31 M5 lines were harvested at Aberdeen,
ID, in 1993 (see note). At Aberdeen in 1994, over 1,000 M6 head-rows
were evaluated for improved plant uniformity and performance,
from which 100 selections were made that included 19 MD germplasms.
Twenty-five head-row selections from this group, representing
seven MD germplasms, were grown in advanced field tests at two
South Dakota and one Nebraska locations in 1994-95. Limited
amounts (5 g) of SDM germplasm seed are available from S.D. Haley,
Plant Science Department, and will be deposited in 1997 at the
National Small Grains Collection, Aberdeen, ID. Kenefick, Gellner,
Koepke, Schut.
Note: Appreciation to D. Wesenberg and staff, USDA-ARS,
National Small Grains Germplasm Research Facility, Aberdeen, ID.
Table 1. Plant height, stand survival, and leaf osmotic potential after 2_C treatment1
of mutant-derived (MD) germplasm lines from Winoka HRWW.
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Plant height2 Stand survival3 Leaf osmotic potential4
SDM line (cm) (%) (-MPa)
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8127 61 82 1.82
16050 63 78 1.77
16029 60 75 1.71
16085 60 68 1.46
16129 61 60 1.46
16091 55 58 1.37
16132 59 48 1.33
16156 63 45 1.22
16149 62 40 1.19
Winoka 78 35 1.80
16166 60 35 1.21
16187 62 35 1.12
16208 59 35 1.21
16169 63 30 1.00
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1 Plants grown in the greenhouse for 28 days, then soil water adjusted to 0.7 soil
saturation before 2_C exposure for 5 weeks during gradual soil drying.
2 Field data from 1985 at Presho, SD with M5 MD lines.
3 Average of duplicate field tests at Casselton, ND, 1988. In the same test, survivals
of cultivars Norstar, Warrior, and Centurk 78 were 88, 60, and 53 %, respectively.
4 Leaf 4: average MPa from three hydrated leaves
per treatment.
Field performance of head-row selections from
mutant-derived (SDM) HRWW germplasm. Duplicate
plots of 25 M6 head-row selections (derived from seven SDM germplasms)
made at Aberdeen, ID, were compared for yield with five commercial
HRWW cultivars at Selby and Pierre, SD, and Mead, NE, in 1995.
No freeze differential occurred at these locations in 1994-95.
Foliar and head blight disease at Mead significantly reduced
yields, restricting valid comparisons at this location. At Pierre,
head-row selection 2381 (derived from SDM 16208) yielded (81 bu/acre),
equal to the cultivars Vona and TAM 101, but less than TAM 107
(88 bu), which had the largest seed yield. One head-row selection
from SDM8127 and three from SDM16029 yielded between 60 and 67
bu/acre. Twenty-three head-row selections yielded better than
Winoka (36 bu/acre), whereas 16 were better than Roughrider (49
bu/acre).
At Selby, two head-row selections from SDM8127 and
one from SDM16029 equaled the yield of Vona (68 bu/acre); yields
of other head-row selections in the test were below this value.
Two head-row selections from SDM8127 yielded the same as TAM
101 (64 bu/acre), whereas a total of seven head-row selections
(SDM8127 and SDM16029 germplasms) yielded more than Roughrider
(57 bu/acre).
Repeat plantings of these trials were made at Brookings,
Selby, and Pierre, SD, for evaluation of yield and stand survival
in 1995-96. Significant variation in leaf osmotic potentials
of greenhouse plants have been observed among head-row selections
within each SDM germplasm line, providing an opportunity to examine
tissue water adjustment after 2_C exposure in similar genetic
material. These MD germplasm lines appear to be good sources
of genetic variation for agronomic improvement of HRWW, having
reduced plant height while maintaining yield and winter hardiness.
Limited amounts (5 g) of head-row selected seed are available
from S.D. Haley, Plant Science Department, and will be deposited
in 1997 at the National Small Grains Collection, Aberdeen, ID.
(D. Kenefick, S. Haley, R. Schut, J. Koepke)
Note: Appreciation to D Wesenberg and staff, USDA-ARS,
National Small Grains Germplasm Research Facility, Aberdeen, ID.
F. Sutton and K. Isaac.
Synthetic cationic lipopolyamines enhance electroporation-mediated
DNA transfer into cereals. Cationic lipopolyamines are used successfully
for transformation of mammalian tissue. Two cationic lipopolyamines
in conjunction with electroporation were tested for successful
delivery of DNA into cereals. Experiments were performed with
plasmid pAHC27, a plasmid bearing the GUS gene under the
control of the ubiquitin promoter. Spectrophotometric and histochemical
GUS assays revealed higher levels of GUS activity
in tissues electroporated with DNA in the presence of the cationic
lipopolyamine. Transfectam (Promega, Inc), in conjunction with
electroporation, caused an increase in GUS activity as
large as 48 times that of DNA alone plus electroporation. Lipofectamine
(Gibco/BRL-Life Technologies, Inc.), in conjunction with electroporation,
resulted in 80 times more GUS activity than DNA alone plus
electroporation. The efficiency of transformation in the presence
of Lipofectamine was 4 times greater for wheat (SD 16029) than
for barley (Dicktoo). This is the first description of cationic
lipopolyamine electroporation mediated transfer of DNA into cereals.
We believe that this protocol will be a successful alternative
to other transformation techniques.