Ba 73-626 Kentucky Bluegrass

Abstract

A variety of kentucky bluegrass having a high level of disease resistance, good turf performance, and a very high level of seed yield potential.

Description

BACKGROUND

Kentucky Bluegrasses having been disclosed in U.S. Plant Pat. No. 3,156 which issued on May 9, 1972; U.S. Plant Pat. No. 3,186 which issued on May 23, 1972; U.S. Plant Pat. No. 4,336 which issued on Nov. 28, 1978; U.S. Plant Pat. No. 6,280 which issued on Sept. 6, 1988; U.S. Plant Pat. No. 6,537 which issued on Jan. 17, 1989; U.S. Plant Pat. No. 6,538 which issued on Jan. 17, 1989; and U.S. Plant Pat. No. 6,585 which issued Feb. 7, 1989.

SUMMARY OF THE VARIETY

The present invention relates to a new and improved variety of Kentucky Bluegrass, Poa pratensis, that has been designated Ba 73-626.

Ba 73-626 plant material originated by crossing a Kentucky Bluegrass plant developed and maintained in the plant nursery as the seed parent with a Kentucky Bluegrass plant selected from PI-198075, a plant introduction from Sweden available from Germplasm Services Laboratory, Beltsville, Md., as the pollen parent. As a result of this breeding, a distinct variety was produced and asexually propagated by rhizomes, tillers and disseminules. Seed of Ba 73-626 was produced first at Marysville, Ohio and later at Gervais, Oreg. This seed was used for purposes of plant turf performance evaluation trials, including those conducted under the auspices of the National Turfgrass Evaluation Program sponsored by the United States Department of Agriculture, Agricultural Research Service and the Maryland State Turfgrass Council.

Asexual reproduction of Ba 73-626 by propagules (tillers and rhizomes) and by disseminules (modified caryopses produced by apomixis) has consistently produced progeny plants indistinguishable from the mother plant. The apomixis level of Ba 73-626 ranged from 100% to 98.8% (mean of 99.4%) based upon examining seedlings from four different crop years under constant growth chamber conditions.

Ba 73-626 has a number of highly desirable characteristics including a good level of resistance to Drechslera spp. (formerly called Helminthosporium spp.) that causes leaf spot, melting out and crown rot; Laetisaria fuciformis that causes red thread; Sclerotinia homoeocarpa that causes dollar spot; Puccinia spp. that causes rust and Phialophora gramincola that causes summer patch (formerly called Fusairum blight). Ba 73-626 has an attractive leafy turf type growth habit; moderately wide leaf blades; attractive green color which can be maintained throughout the entire growing season; good seedling vigor and heat tolerance; good turf performance as evidenced by consistently high scores in National Turfgrass Evaluation Tests sponsored by the United States Department of Agriculture and conducted throughout the U.S.A. and Canada and a very high seed yield potential in the bluegrass seed production region of the U.S.A.

In comparison with most commercially available varieties, the new Ba 73-626 variety has a thicker peduncle, a wider and thicker flag leaf, higher seed yield, wider leaf blades and better winter color. In comparison to the pollen parent, the new variety has fewer seeds per pound, a much higher seed yield and more erect culms of mature unmowed plants.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows a Ba 73-626 Kentucky Bluegrass plant in the vegetative stage including the extensive root and rhizome system;

FIG. 2 shows a Ba 73-626 Kentucky Bluegrass panicle; and

FIG. 3 shows Ba 73-626 Bluegrass seed.

DETAILED DESCRIPTION OF THE VARIETY

Ba 73-626 Kentucky Bluegrass (Poa pratensis L.) is perennial with creeping rhizomes forming a moderately dense turf. When plants overwinter in the field with freezing temperatures and are then brought into the greenhouse during late winter to continue growth undisturbed by clipping under moderate temperatures (60°-80° F.), culms are erect averaging 514 mm in length with an average of 2.3 nodes per culm. The uppermost internode averages 12.4 cm, and the peduncle averages 12.3 cm in length, and 0.772 mm in thickness. The flag leaf averages 5.8 cm in length, 4.2 mm in width and 0.119 mm in thickness. The panicle has an average length of 9.7 cm, width of 6.0 cm, and 5.5 whorls. The lowest whorl has an average of 4.5 branches and the third whorl from the bottom of the panicle has an average of 3.4 branches. The average spikelet at the tip of a branch in the lowest whorl is 5.8 mm in length and has 4.4 florets with an outer glume of 3.2 mm and an inner glume of 3.7 mm in length. A similar spikelet from the third whorl from the bottom of the panicle is 5.6 mm in length and has 4.1 florets with an outer glume of 3.3 mm and an inner glume of 3.6 mm in length. After the seed has been conditioned, the lemma has a generally smooth keel with occasional short hairs and a few long fine hairs at the base. The seed of Ba 73-626 is 2.98 mm in length and 0.80 mm in width with approximately 921,166 seeds per pound. Comparisons of Ba 73-626 with other varieties in terms of seed dimensions and seed numbers per pound are shown in Tables 1 and 2 as follows:

TABLE 1
______________________________________
Seed Measurements of Ba 73-626 and Other Bluegrass
Varieties After Conditioning.
Length  Width
Variety          (mm)    (mm)
______________________________________
Ba 73-626        2.98    0.80
Abbey            3.18    0.88
Coventry         2.86    0.78
Estate           2.53    0.76
Chateau          2.77    0.80
Baron            3.07    0.86
Bristol          2.73    0.80
Nassau           2.96    0.78
Newport          2.76    0.71
Park             3.04    0.72
Ram I            3.51    0.84
Victa            3.20    0.86
LSD (.05)        0.19    0.06
______________________________________

TABLE 2
______________________________________
Comparison of Seed Numbers Per Pound of Ba 73-626
and Other Bluegrass Varieties After Conditioning.
Number of Seeds
Per Pound
______________________________________
Ba 73-626      921,166
Abbey        1,003,037
Coventry     1,246,200
Estate       1,275,740
Chateau      1,300,105
Adelphi      1,383,976
America      1,659,824
Gnome        1,017,641
Baron        1,051,693
Birka        1,223,530
Bonnieblue   1,135,303
Bristol      1,270,821
Eclipse      1,335,668
Fylking      1,130,000
Glade        1,108,441
Kenblue      1,463,923
Merit        1,109,728
Nassau       1,127,130
Newport      1,226,481
Park         1,248,349
Sydsport     1,355,644
Vantage      1,555,303
Victa        1,038,298
Windsor      1,520,885
______________________________________

Since environmental conditions such as soil and climate may influence morphological characteristics to some extent, comparisons of morphological characteristics of Ba 73-626 are made with other Kentucky Bluegrass varieties in the following Tables 3-10:

TABLE 3
______________________________________
Morphological Comparison of Panicles of Ba 73-626
and Other Bluegrass Varieties in the Greenhouse
at Marysville, Ohio.
No. of
Panicle
Panicle Whorls  No. of Branches
Panicle  Length  Width Per   Lower Third
Variety Nodding* (cm)    (cm)  Panicle
Whorl Whorl
______________________________________
Ba 73-626
1.3      9.7     6.0   5.5   4.5   3.4
Abbey   1.4      7.6     4.2   5.2   4.0   2.7
Baron   1.0      7.8     4.1   5.2   3.8   2.5
Bristol 2.0      9.7     5.0   5.0   3.3   2.7
Chateau 2.0      6.8     3.8   5.0   4.0   2.4
Coventry
2.0      6.7     3.7   4.8   3.8   2.7
Estate  1.2      7.5     4.2   5.5   4.0   3.0
Nassau  2.0      10.0    6.0   5.0   3.0   2.0
Newport 2.0      10.3    4.4   4.5   2.3   2.3
Park    1.6      9.0     3.7   4.0   4.3   3.7
Ram I   2.0      9.0     4.7   4.0   2.5   2.0
Victa   1.2      7.5     4.1   5.4   4.4   3.4
LSD (.05)
0.5      1.6     1.0   0.8   0.7   0.8
______________________________________
*Panicle nodding rated: 1 = erect, 2 = nodding

TABLE 4
______________________________________
Morphological Comparison of Spikelets of Ba 73-626
and Other Bluegrass Varieties in the Greenhouse
at Marysville, Ohio.
Spikelet         No. of Florets
Length (mm)      per Spikelet
Lowest  Third      Lowest
Third
Variety    Whorl   Whorl      Whorl Whorl
______________________________________
Ba 73-626  5.8     5.6        4.4   4.1
Abbey      5.1     5.0        3.9   3.8
Baron      5.0     5.0        3.7   3.8
Bristol    6.2     6.0        5.7   5.3
Chateau    5.1     5.0        4.2   3.9
Coventry   5.2     5.2        4.2   4.0
Estate     5.2     5.0        4.2   4.2
Nassau     4.6     4.6        4.5   4.5
Newport    5.3     5.2        5.2   5.2
Park       6.5     6.7        5.2   4.7
Ram I      4.7     5.2        5.2   5.5
Victa      5.2     5.0        3.8   3.8
LSD (.05)  0.9     0.8        1.1   1.0
______________________________________

TABLE 5
______________________________________
Morphological Comparison of Glumes of Ba 73-626
and Other Bluegrass Varieties in the Greenhouse
at Marysville, Ohio.
Glume Length (mm)
Outer            Inner
Lowest  Third      Lowest
Third
Variety    Whorl   Whorl      Whorl Whorl
______________________________________
Ba 73-626  3.2     3.3        3.7    3.6
Abbey      2.9     2.9        3.3    3.3
Baron      2.9     2.8        3.4    3.3
Bristol    3.4     3.3        3.7    3.9
Chateau    3.1     3.1        3.4    3.4
Coventry   3.2     3.1        3.5    3.5
Estate     2.9     3.0        3.3    3.3
Nassau     2.3     2.4        2.7    2.7
Newport    2.6     2.5        2.9    2.9
Park       3.0     3.2        3.5    3.7
Ram I      2.6     2.4        2.9    2.7
Victa      2.8     3.0        3.3    3.3
LSD (.05)  0.5     0.4        0.4    0.4
______________________________________

TABLE 6
______________________________________
Morphological Comparison of Flag Leaves of Ba 73-626
and Other Bluegrass Varieties in the Greenhouse at
Marysville, Ohio.
Flag Leaf   Flag Leaf Flag Leaf
Length      Width     Thickness
Variety   (cm)        (mm)      (mm)
______________________________________
Ba 73-626 5.8         4.2       0.119
Abbey     4.3         3.3       0.107
Baron     4.5         3.2       0.119
Bristol   5.5         3.4       0.127
Chateau   4.1         3.2       0.111
Coventry  4.7         3.2       0.112
Estate    5.2         3.6       0.117
Nassau    6.2         3.1       0.127
Newport   6.1         3.5       0.135
Park      4.2         2.6       0.110
Ram I     4.7         3.1       0.127
Victa     5.9         4.0       0.124
LSD (.05) 1.8         0.6       0.013
______________________________________

TABLE 7
______________________________________
Morphological Comparison of Peduncles, Culms, and
Internodes of Ba 73-626 and Other Bluegrass
Varieties in the Greenhouse at Marysville, Ohio.
No. of Top
Peduncle Peduncle Culm  Nodes  Internode
Length   Width    Length
Per    Length
Variety (cm)     (mm)     (mm)  Culm   (cm)
______________________________________
Ba 73-626
12.3     0.772    514   2.3    12.4
Abbey   10.6     0.564    421   2.7     9.3
Baron   12.7     0.555    482   2.5    10.1
Bristol 15.0     0.677    522   2.7    11.3
Chateau 12.9     0.654    439   2.7     9.8
Coventry
13.2     0.607    435   2.7    10.2
Estate  12.6     0.552    486   2.2    10.5
Nassau   8.0     0.546    450   2.5    11.2
Newport 18.0     0.567    547   2.3    11.2
Park    14.3     0.779    578   3.0    13.0
Ram I   18.5     0.622    527   3.0    10.2
Victa   12.2     0.716    474   2.4    10.6
LSD (.05)
3.7     0.018     79   0.6     2.1
______________________________________

TABLE 8
______________________________________
Morphological Comparison of Leaves of Ba 73-626 and
Other Bluegrass Varieties in the Greenhouse at
Marysville, Ohio.
Ligule  Leaf      Leaf  Leaf Angle
Length  Length    Width (Degrees
Variety  (mm)    (mm)      (mm)  From Horizontal)
______________________________________
Ba 73-626
0.29    215       4.4   46
Abbey    0.23    218       3.9   56
Baron    0.30    313       4.4   63
Bristol  0.30    253       4.3   37
Chateau  0.25    204       4.1   50
Coventry 0.26    218       4.1   55
Estate   0.28    239       4.4   52
Nassau   0.22    226       3.5   39
Newport  0.22    251       4.1   50
Park     0.33    329       4.2   44
Ram I    0.18    188       3.7   40
Victa    0.28    235       4.3   52
LSD (.05)
0.11     49       0.6   10
______________________________________

TABLE 9
______________________________________
Morphological Comparison of Leaf Hairs of Ba 73-626
and Other Bluegrass Varieties in the Greenhouse at
Marysville, Ohio.
Hairs Around Ligule
on Upper Surface Hairs on Hairs on
Variety of the Leaf(a)
Collar(a)
Ligule(b)
______________________________________
Ba 73-626
1.2              4.2      3.6
Abbey   1.0              3.4      2.2
Baron   1.0              5.0      4.0
Bristol 1.3              4.7      4.3
Chateau 1.0              3.5      2.7
Coventry
1.0              3.5      1.5
Estate  1.0              3.2      1.3
Nassau  2.7              5.0      1.0
Newport 1.0              4.0      0.8
Park    1.0              1.7      0.0
Ram I   1.0              3.7      0.3
Victa   1.0              3.3      2.2
LSD (.05)
0.3              1.4      1.8
______________________________________
(a) Hairs around ligule and on collar rated 1-5: 1 = none, 5 = many
(b) Hairs on ligule rated 0-5: 0 = none, 5 = many

TABLE 10
______________________________________
Morphological Comparisons of Ba 73-626 and Other
Bluegrass Varieties Grown as Unmowed Spaced Plants
in the Field at Marysville, Ohio.
Mature
Plant Height(a)
Panicle Density(b)
Maturity(c)
______________________________________
Ba 73-626
50           5            8
Abbey   49           5            7
Baron   44           5            9
Coventry
48           5            7
Nassau  46           6            9
Bristol 54           3            8
Merit   61           5            9
Glade   49           2            9
Ram I   49           3            7
Victa   54           6            8
______________________________________
Ratings:
(a) Mature Plant Height (cm) includes panicle
(b) Panicle Density  1-10, 10 = high panicle density
(c) Maturity  1-9, 9 = most mature

No discernible differences were noted in flower parts and seed coloration other than those characteristics listed in the above tables.

Ba 73-626 has performed well in regions throughout the United States, as exhibited by high turf quality ratings in many different locations in comparison with other varieties. In addition, Ba 73-626 has a pleasant medium green color which can be maintained throughout the growing season, good winter color, and early spring greening. Comparisons of Ba 73-626 with other varieties for quality and color are set forth in Tables 11-13 hereinafter. According to comparisons with the Munsell Book for Color during mid-June, the color of Ba 73-626 leaf blades is in the range of 5 GY 4/4 to 5 GY 4/8 to 7.5 GY 4/4. During the same time period the color of similar leaf blades of several other Kentucky Bluegrass varieties--Gnome, Midnight, Bristol and Victa--fell in the same range and as a result were indistinguishable based upon use of this color dictionary. Plant age, time of year, management practices of fertilization, irrigation and mowing also influence this color range. Additional comparisons for seedling vigor, drought tolerance, leaf texture, density, seed yield and sod strength are shown in Tables 14-19.

TABLE 11
__________________________________________________________________________
A Comparison of Turf Quality(a) of Ba 73-626
and Other Bluegrass Varieties at Various Testing
Locations in the United States
Testing Locations
Variety
NC KS  OH OK  VA IN  NE NJ Mean
__________________________________________________________________________
Ba 73-626
5.0
7.5 6.7
5.8 4.9
6.9 6.1
5.8
6.1
Abbey  3.8
7.1 5.8
5.2 5.2
6.8 5.7
6.3
5.7
Able I 4.2
6.6 5.9
4.8 4.4
6.8 5.3
6.0
5.5
Amazon 3.5
6.9 6.4
6.2 4.4
5.0 4.8
4.9
5.3
America
4.3
7.3 6.8
4.9 4.8
6.8 5.0
5.8
5.7
Aquila 3.5
5.9 5.7
5.3 4.1
6.7 6.3
6.1
5.5
A-34   3.5
7.4 6.7
6.3 4.4
6.8 5.5
4.3
5.6
Baron  5.2
7.5 6.0
4.8 4.6
6.8 5.6
5.3
5.7
Barzan 4.2
7.1 4.9
3.5 4.4
7.0 5.2
5.5
5.2
Bristol
3.7
7.5 6.7
5.3 4.4
6.6 4.7
6.0
5.6
Chateau
4.8
7.4 6.8
4.4 5.0
6.1 6.2
5.5
5.8
Classic
3.5
7.2 6.0
5.5 4.2
6.6 5.8
5.2
5.5
Coventry
3.8
7.2 6.6
5.1 5.0
6.5 5.5
5.2
5.6
Estate 4.7
7.0 6.6
5.3 4.7
6.5 5.8
5.8
5.8
Georgetown
3.8
7.0 5.9
4.5 4.5
6.4 5.4
4.7
5.3
Glade  3.8
7.7 6.6
3.8 4.8
7.0 5.7
5.3
5.6
Gnome  4.3
6.9 5.4
5.1 4.7
6.5 5.4
5.4
5.5
Haga   3.8
7.1 6.2
5.6 5.0
6.6 5.2
4.5
5.5
Julia  3.7
6.7 6.4
5.4 4.7
5.5 6.0
5.5
5.5
Kenblue
4.2
4.8 4.8
3.6 3.7
6.0 4.9
3.7
5.5
Liberty
3.8
7.1 5.9
4.8 4.5
6.4 5.2
5.1
5.4
Merion 4.0
7.0 5.9
3.7 4.3
6.6 5.9
4.8
5.3
Merit  5.2
7.4 6.2
4.2 4.6
7.0 5.6
5.7
5.7
Midnight
3.7
8.1 6.8
4.7 4.7
7.1 6.3
6.9
6.0
Monopoly
4.7
6.5 5.1
5.2 4.9
6.9 5.3
4.7
5.4
Mystic 4.2
6.2 6.4
3.8 3.4
7.2 5.7
5.4
5.3
Nassau 3.5
7.7 6.4
4.7 4.7
6.1 5.3
5.3
5.5
Parade 3.7
7.3 5.6
4.8 3.8
6.2 6.0
4.6
5.3
Ram I  4.2
6.5 6.6
4.9 4.8
5.8 5.3
6.0
5.5
Rugby  3.8
7.0 6.0
4.7 4.4
6.4 5.6
4.8
5.3
Sydsport
3.8
7.5 6.6
4.4 5.3
6.2 5.1
5.0
5.5
Victa  5.0
7.5 6.3
4.1 5.2
6.8 6.0
6.0
5.9
Wabash 4.5
6.7 5.9
5.1 4.1
6.8 6.0
4.0
5.4
Welcome
3.7
6.7 6.3
3.7 4.5
6.9 5.4
5.5
5.3
LSD 0.05
1.1
0.7 1.0
1.7 0.8
0.7 1.0
1.1
__________________________________________________________________________
(a) Rating Scale 1-9: 9 = best quality

TABLE 12
______________________________________
A Comparison of Turf Color(a) of Ba 73-626 and
Other Bluegrass Varieties at Various Testing
Locations in the United States.
Wichita    Post Falls
Silver Springs
Variety  Kansas     Idaho     Maryland
______________________________________
Ba 73-626
7.3        8.0       8.0
Abbey    8.0        7.7       6.7
Able I   8.3        7.3       7.3
Adelphi                       7.7
Amazon   6.0        7.3       7.7
America  8.3        7.7
Aquila   8.0        6.0       6.7
A-34     6.7        6.3       5.7
Baron    7.7        7.7       8.3
Barzan   7.0        6.7       8.0
Bristol  8.3        8.0       7.3
Chateau  7.3        7.0       7.0
Classic  6.0        7.0       6.3
Coventry 7.3        7.0       7.3
Estate   7.3        7.0       6.7
Georgetown
6.7        7.0       6.3
Glade    7.7        7.7       8.0
Gnome    7.3        8.0       7.0
Haga     6.3        7.0       5.7
Julia    7.3        7.7       7.7
Kenblue  6.0        6.7       6.0
Liberty  7.7        6.7       6.7
Merion   7.7        5.3       7.0
Merit    7.0        8.0       7.0
Midnight 8.7        8.0       8.3
Monopoly 5.3        6.0       6.0
Mystic   7.3        6.7       7.3
Nassau   7.7        7.3       7.7
Parade   7.3        7.3       6.3
Ram I    8.0        8.0       8.3
Rugby    7.0        6.0       6.0
Sydsport 8.0        7.3       7.0
Victa    8.0        8.0       8.0
Wabash   6.3        6.0       6.0
Welcome  7.0        6.7       7.3
LSD (.05)
1.0        1.5       0.9
______________________________________
(a) Rating Scale 1- 9: 9 = best color

TABLE 13
______________________________________
Winter Color(a) of Ba 73-626 and Other Bluegrass
Varieties
Testing Locations
Puyallup  Agassiz
Variety      Washington
British Columbia
______________________________________
Ba 73-626    6.0       4.7
Abbey        5.7       4.7
Able I       7.0       4.0
Amazon       2.7       4.0
America      6.3       4.0
Aquila       4.0       4.0
A-34         6.0
Baron        4.7       4.7
Barzan       2.0       5.0
Bristol      8.0       5.0
Chateau      4.3       5.0
Classic      6.3       4.0
Coventry     4.7       5.0
Estate       4.0       5.0
Georgetown   5.7       4.0
Glade        6.0       4.3
Gnome        5.7       4.3
Haga         6.0       4.0
Julia        6.0       5.0
Kenblue      1.3       3.0
Liberty      6.7
Merion       6.3       4.0
Merit        5.7       5.0
Midnight     6.3       4.7
Monopoly     6.0       4.7
Mystic       1.3       2.7
Nassau       7.3       5.0
Parade       6.0       4.0
Ram I        3.7       4.7
Rugby        5.7       4.3
Sydsport     4.3       5.0
Victa        6.7       5.0
Wabash       3.3       3.3
Welcome      1.3       5.0
LSD 0.05     1.6       0.6
______________________________________
(a) Rating Scale: 1-9 Larger number indicates greener color

TABLE 14
______________________________________
Comparison of Seedling Vigor(a) of Ba 73-626 and Other
Bluegrasses
Testing Location
Variety      Ritzville, Washington
______________________________________
Ba 73-626    3.0
Abbey        1.3
Able I       1.7
Amazon       1.7
America      1.7
Aquila       1.3
A-34         2.3
Baron        2.0
Barzan       2.7
Bristol      2.7
Chateau      1.7
Classic      2.3
Coventry     2.3
Estate       1.3
Georgetown   2.0
Glade        2.0
Gnome        2.3
Haga         2.3
Julia        1.7
Kenblue      1.3
Liberty      1.7
Merion       1.3
Merit        1.3
Midnight     1.0
Monopoly     2.0
Mystic       2.7
Nassau       2.0
Parade       1.0
Ram I        2.0
Rugby        1.7
Sydsport     1.7
Victa        3.0
Wabash       1.0
Welcome      1.7
LSD 0.05     1.3
______________________________________
(a) Rating Scale: 1-9 9 = most vigor

TABLE 15
______________________________________
Comparison of Drought and Heat Tolerance(a) of
Ba 73-626 and Other Bluegrasses
Testing Locations
Post Falls
Marysville
Variety        Idaho     Ohio
______________________________________
Ba 73-626      7.7       6.3
Abbey          7.7       6.3
Able I         7.7
Adelphi                  5.7
Amazon         7.0
America        8.0
Aquila         7.3
A-34           6.0
Baron          7.0       6.0
Barzan         6.0
Bonnieblue               6.0
Bristol        6.7       6.0
Chateau        7.0       6.0
Classic        7.3       5.3
Coventry       7.3       6.0
Estate         7.0       6.0
Georgetown     6.7       4.7
Glade          6.7       6.3
Gnome          8.0       6.3
Haga           6.7
Julia          7.3
Kenblue        6.3
Liberty        7.7
Merion         7.3       5.0
Merit          8.0       6.0
Midnight       6.0
Monopoly       6.7
Mystic         7.7
Nassau         8.0       6.0
Newport                  6.0
Parade         5.7
Park                     5.0
Ram I          8.7       6.0
Rugby          7.0
Sydsport       7.0
Vantage                  6.0
Victa          7.7
Wabash         6.7       4.0
Welcome        7.3
LSD 0.05       1.7       0.9
______________________________________
(a) 1-9 Scale 9 = most tolerant

TABLE 16
______________________________________
Comparison of Leaf Texture(a) of Ba 73-626 and
Other Bluegrasses Under Mowed Conditions
Testing Locations
Puyallup  Agassiz
Variety       Washington
British Columbia
______________________________________
Ba 73-626     3.7       5.3
Abbey         5.3       5.7
Able I        7.7       6.0
Amazon        6.0       6.3
America       7.7       6.0
Aquila        7.0       6.0
A-34          6.7       5.7
Baron         4.3       6.0
Barzan        5.7       6.0
Bristol       6.0       5.0
Chateau       4.3       5.7
Classic       7.3       6.0
Coventry      4.3       5.3
Estate        4.7       5.7
Georgetown    8.0       5.3
Glade         6.7       6.0
Gnome         5.3       5.3
Haga          7.7       6.0
Julia         6.0       6.0
Kenblue       5.3       6.7
Liberty       6.0
Merion        8.0       6.0
Merit         4.0       6.0
Midnight      6.0       6.0
Monopoly      7.0       6.0
Mystic        6.0       7.3
Nassau        7.0       5.0
Parade        7.0       6.0
Ram I         6.3       6.3
Rugby         6.3       6.0
Sydsport      5.0       6.0
Victa         3.3       5.7
Wabash        7.0       6.3
Welcome       6.3       6.0
LSD 0.05      1.4       0.6
______________________________________
(a) Rating Scale 1-9 9 = finest leaf

TABLE 17
______________________________________
A Comparison of the Average Spring and Summer
Density(a) of Ba 73-626 and Other Bluegrasses at
Various Locations(b)
Variety         Spring  Summer
______________________________________
Ba 73-626       6.1     7.2
Abbey           6.3     7.2
Baron           6.1     7.2
Chateau         6.6     7.3
Classic         6.9     7.3
Coventry        6.7     7.3
Estate          6.1     7.3
Glade           5.9     7.3
Gnone           5.8     6.9
Kenblue         5.9     6.8
Merion          6.3     6.9
Merit           6.0     6.9
Midnight        6.1     7.7
Nassau          5.7     6.8
Parade          6.2     7.3
Ram I           6.6     7.3
Victa           5.8     7.1
LSD 0.05        0.8     0.6
______________________________________
(a) Rating Scale 1-9: 9 = Maximum
(b) The testing locations were in Indiana, Ohio and Manitoba, Canada
for both spring and summer testing.

TABLE 18
______________________________________
Seed Yield Comparisons(a) of Ba 73-626 and Other
Bluegrass Varieties in Gervais, Oregon
Variety    Year 1  Year 2     Year 3
Year 4
______________________________________
Ba 73-626  672     1136       760   1265
Abbey      691     1586
Bristol    347      808       627    684
Chateau    559      757
Coventry   643      930
Estate     585      864
Julia      296     1016
Mosa       322     1060
Newport    435     1256
Victa      780     1394       855   1287
LSD 0.05   140      134       105    131
______________________________________
(a) Seed yields: Pounds per acre

TABLE 19
______________________________________
Comparison of Sod Strength(a) of Ba 73-626 and
Other Bluegrasses under Mowed Conditions
Testing Location
Variety        Remington, Virginia
______________________________________
Ba 73-626      14.3
A-34            9.7
Able I          8.7
Amazon          8.7
America        18.7
Aquila         16.3
Baron          14.7
Barzan          8.3
Bristol         8.3
Chateau        15.0
Classic        15.3
Coventry       11.0
Estate         16.0
Georgetown     14.3
Glade          18.0
Gnome          14.3
Haga           13.0
Julia          11.0
Kenblue        16.3
Liberty        11.0
Merion         11.3
Merit          13.3
Midnight       14.3
Monopoly        8.3
Mystic         14.3
Nassau          8.3
Parade         12.7
Ram I          11.0
Rugby          11.7
Sydsport       20.7
Victa          16.3
Wabash         10.3
Welcome        18.0
LSD (0.05)      6.1
______________________________________
(a) Sod strength measured in kilograms of tension needed to tear sod

Turf diseases are one of the major causes of inconsistent and poor turf performance. Ba 73-626 has been found to have a high level of resistance to leaf spot (also known as melting out and crown rot) caused by Drechslera poae (formerly called Helminthosporium vagans), a medium to high level of resistance to rust caused by Puccinia spp., to dollarspot caused by Sclerotinia homoeocarpa, to red thread caused by Laetisaria fuciformis formerly called Corticium, to summer patch caused by Phialophora graminicola formerly called a Fusarium spp and to necrotic ring spot caused by Leptosphaeria korrae.

Comparisons of Ba 73-626 with other varieties regarding resistance to leaf spot, rust, dollarspot, red thread and summer patch are presented in Tables 20-23.

TABLE 20
______________________________________
Comparison of Leafspot Disease Incidence on
Ba 73-626 And Other Bluegrasses
Testing Locations
Marysville  Blacksburg
Puyallup
Variety  Ohio(a)
Virginia(b)
Washington(b)
______________________________________
Ba 73-626
8.3        6.0       8.3
Abbey                6.0       8.0
Able I               4.7       9.0
Adelphi  20.0
Amazon               5.3       7.0
America              5.3       8.7
Aquila               4.3       7.3
A-34                 5.3       8.7
Baron    10.0        5.7       8.3
Barzan               5.3       3.3
Bonnieblue
13.3
Bristol              5.7       9.0
Chateau              5.7       9.0
Classic              5.3       8.7
Coventry 11.7        5.7       9.0
Estate               5.3       9.0
Georgetown           5.7       9.0
Glade    11.7        5.5       8.0
Gnome                5.7       8.7
Haga                 5.7       9.0
Julia                6.0       9.0
Kenblue              2.3       1.0
Liberty              5.7       8.7
Merion   18.3        6.0       9.0
Merit    20.3        6.0       8.3
Midnight             5.3       9.0
Monopoly             4.7       8.0
Mystic               4.7       1.0
Nassau               6.0       9.0
Newport  46.7
Parade               4.3       9.0
Park     60.0
Ram I    16.7        5.0       5.3
Rugby                4.7       9.0
Sydsport 11.7        6.3       9.0
Vantage  45.0
Victa    15.0        6.0       8.0
Wabash               2.3       6.3
Welcome              4.3       1.3
LSD 0.05 17.6        1.1       1.6
______________________________________
(a) Results expressed in % of turf affected by disease
(b) Results rated on scale of 1-9: 9 = least disease

TABLE 21
______________________________________
Comparison of Stem and Leaf Rust(a) (Puccinia spp.)
Disease Incidence on Ba 73-626 and Other Bluegrasses
Testing Locations
Adelphia   Riverside Post Falls
New Jersey California
Idaho
Variety    Stem Rust  Leaf Rust Leaf Rust
______________________________________
Ba 73-626  7.3        5.7       8.7
Abbey      6.3        5.3       8.3
Able I     7.0        6.3       8.3
Amazon     6.0        5.3       7.7
America    8.3        6.0       8.7
Aquila     8.0        5.7       7.7
A-34       8.0        6.3       7.7
Baron      7.3        5.0       8.0
Barzan     8.0        5.7       7.7
Bristol    8.7        6.0       8.7
Chateau    8.3        5.3       8.0
Classic    8.7        6.0       9.0
Coventry   8.3        5.0       7.3
Estate     7.3        5.7       8.0
Georgetown 9.0        6.0       8.3
Glade      7.7        5.0       8.7
Gnome      7.7        5.3       8.3
Haga       9.0        6.3       8.3
Julia      8.0        5.7       8.0
Kenblue    8.3        5.7       7.7
Liberty    8.3        6.7       8.0
Merion     2.7        4.0       6.7
Merit      8.0        5.7       9.0
Midnight   8.3        5.7       7.7
Monopoly   8.0        5.3       8.3
Mystic     5.3        5.7       7.3
Nassau     7.7        5.7       8.0
Parade     9.0        7.0       7.7
Ram I      8.7        6.0       8.7
Rugby      8.7        6.7       8.3
Sydsport   8.0        5.3       8.3
Victa      7.7        4.7       7.3
Wabash     8.0        5.3       8.0
Welcome    7.3        6.0       8.3
LSD 0.05   1.0        1.5       1.4
______________________________________
(a) Results rated on a scale of 1-9: 9 = least disease

TABLE 22
______________________________________
A Comparison of Red Thread, Summer Patch, Necrotic
Ring Spot and Dollar Spot(a) Incidence Level on
Ba 73-626 and Other Bluegrasses at Various
Locations in the United States.
Testing Locations
West
Blacksburg,
Lafayette,
Hubbard,
Virginia  Indiana   Oregon  Columbia,
Red       Summer    Necrotic
Missouri
Variety  Thread    Patch     Ring Spot
Dollarspot
______________________________________
Ba 73-626
5.7       9.0       6.3     7.7
Abbey    6.0       8.0       6.0     6.7
Able I   3.7       8.7       7.3     6.3
Amazon   3.0       4.3       5.0     5.7
America  5.3       9.0       7.0     7.0
Aquila   3.7       9.0       6.0     7.7
A-34     4.3       8.3       5.0     7.3
Baron    4.7       8.7       5.3     7.7
Barzan   4.0       8.0       6.0     6.0
Bristol  5.7       9.0       6.0     7.3
Chateau  4.7       6.7       5.0     6.0
Classic  5.0       8.7       4.7     6.7
Coventry 5.0       7.3       6.3     7.7
Estate   4.3       7.3       6.7     7.3
Georgetown
4.7       8.7       5.7     6.7
Glade    3.3       9.0       7.0     6.7
Gnome    4.0       7.0       6.7     7.7
Haga     4.0       9.0       5.3     7.7
Julia    3.0       5.3       7.3     6.7
Kenblue  2.7       8.3       6.7     7.0
Liberty  4.3       8.7       6.0     7.0
Merion   3.3       8.0       7.7     7.3
Merit    4.0       9.0       6.0     5.0
Midnight 5.0       9.0       7.3     5.7
Monopoly 5.7       9.0       5.0     7.0
Mystic   1.7       9.0       6.7     7.3
Nassau   4.3       7.3       6.0     6.0
Parade   5.0       7.3       5.0     6.3
Ram I    4.3       4.3       7.0     4.3
Rugby    4.7       8.7       5.3     7.3
Sydsport 4.3       7.3       6.7     6.7
Victa    5.7       8.0       6.3     7.0
Wabash   3.3       9.0       4.7     5.7
Welcome  4.0       8.3       6.0     8.3
LSD 0.05 1.4       2.6       1.0     1.9
______________________________________
(a) Results rated on scale of 1-9: 9 = least disease

Claims

1. A variety of kentucky bluegrass plant, substantially as shown and described, characterized by a medium to high level of resistance to several serious diseases, including leaf spot disease, a desirable green color throughout the growing season, a strong sodformer, a high quality dense persistent turf under a wide variety of environmental conditions and a high level of seed yielding capacity.