Perennial St. Augustinegrass having plant hopper and southern chinch bug insect resistance, narrow leaf blades and slower leaf extension rates over time when compared with other St. Augustinegrass varieties thus requiring less frequent mowing.
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Genus and species: Stenotaphrum secundatum (Walt.) Kuntze
Variety denomination: NUF-76
This invention relates to a new and distinct St. Augustinegrass that is the result of a complex hybridization program to develop a dark green, fine bladed St. Augustinegrass. Parents were selected for darker green foliage color, narrow leaf width, low maintenance and resistance to common insect pests and disease. This genotype was first labeled as FA 1997-108 and evaluated as NUF-76. This selection was propagated vegetatively to provide planting stock for studying performance and distinguishing NUF-76 from other St. Augustinegrass cultivars. The St. Augustinegrass ‘NUF-76’ has been asexually propagated through vegetative cuttings of stolons in Florida beginning in 2005.
This application claims the benefit of U.S. provisional patent, application number 60/879,996 filed Jan. 10, 2007.
NUF-76 is a fine bladed, dark green St. Augustinegrass, Stenotaphrum secundatum that is resistant to the southern chinch bug, Blissus insularis and the plant hopper, Liburnia pseudoseminigra. NUF-76 has slow leaf extension growth rates that result in the need for reduced frequency of mowing, there by saving on fuel necessary for lawn maintenance and for wear and tear of the lawn mower.
Insect and Disease Resistance
NUF-76 is resistant to two common insect pests, the southern chinch bug, Blissus insularis and the plant hopper (Tables 1 and 2). NUF 76 is the first St. Augustinegrass known to the inventor reported to have resistance to the plant hopper, Liburnia pseudoseminigra. Plant hoppers feeding solely on NUF-76 survive 3.2 days on average compared with susceptible host plants in which they survived 11.2 or more days. Reproduction occurred on the susceptible host Classic and Palmetto, as evident by nymph production.
TABLE 1
Survival Liburnia pseudoseminigra plant hopper on
NUF-76 and comparison St. Augustinegrasses2.
Variety/Selection
Days of Survival
Classic1 (unpatented)
18.2
a
Palmetto1 (U.S. Plant
13.0
ab
Pat. No. 9395)
Bitterblue1 (unpatented)
11.2
b
Seville1 (U.S. Plant Pat.
8.2
be
No. 4097)
Floratam (unpatented)
3.4
c
FX-10 (U.S. Plant Pat.
3.4
c
No. 7852)
NUF-216 (unpatented)
3.2
c
FSHA-115 (unpatented)
3.2
c
NUF-76
3.2
c
Floralawn (unpatented)
2.6
c
1Plant hoppers survived past the 20 day duration of this experiment, at which point host plant fitness to support plant hopper survival diminishes.
2Means followed by the same letter are not significantly different (alpha = 0.05) using a protected LSD test (SAS 1996)
NUF-76 is resistant to all tested populations of southern chinch bugs from the state of Florida, including those that kill Floratam. For many southern chinch bug populations, mortality on NUF-76 was 100% within the 14 day test period. Chinch bug survival was significantly higher for Floratam and Floratine. Mortality on NUF-76 was similar to FX-10 and NUF-216, both selections having large leaves compared to NUF-76.
TABLE 2
Percent mortality of southern chinch bug, Blissus
insularis feeding on NUF-76 and comparison
St. Augustinegrass held two weeks on each cultivar.
Chinch bugs collected from nine cities or their
suburbs in geographic regions of Florida1.
Variety
Mortality (%)
SD
Range
FX-10
94.9 a
10.3
69-100
NUF-216
94.6 a
9.6
71-100
NUF-76
91.3 a
12.1
63-100
Floratine
60.6 b
23.8
14-95
(unpatented)
Floratam
47.2 b
27.9
0-71
1Means followed by the same letter are not significantly different (P = 0.05) using a protected LSD test (SAS 1996).
Leaf Extension Rate
Leaf extension rate of NUF-76 was always shorter than all other St. Augustinegrass varieties known to the inventor, but was always statistically equal to Seville. Leaf extension rate of NUF-76 was equal to Seville and FX-10 and significantly less than NUF-216 and Floratam seven days after mowing. At 14 days after mowing, leaf growth was similar to Seville and FX-10. NUF-76 was half the height of Floratam and 60% the height of NUF-216. Three weeks after mowing, leaf growth of NUF-76 averaged 7.6 cm which was similar to Seville and 2.5 times shorter than Floratam. NUF-76 is shorter after 21 days of growth, than Floratam after 7 days. Using cultivars with slower leaf extension rates such as NUF-76 can reduce the frequency of mowing, thereby reducing the amount of fuel required to maintain a lawn and also reduce wear and tear of the mower. In a state such as Florida where more than 4 million acres of turfgrass is managed, elimination of a single mowing will result in significant fuel savings.
TABLE 3
Leaf blade growth of NUF-76 and comparison St. Augustinegrasses
one, two and three weeks after mowing1.
Leaf Growth from Last Mowing (cm)
Variety
7 days
14 days
21 days
NUF-76
3.8 c
6.0 c
7.6 d
Seville
5.4 c
6.3c
8.4 d
FX-10
4.6 c
7.4 c
10.3 c
NUF-216
7.2 b
9.8 b
13.6 b
Floratam
9.6 a
13.0 a
19.0 a
1Means followed by the same letter are not significantly different (P = 0.05) using a protected LSD test (SAS 1996).
Leaf Morphology
Unmowed NUF-76 has significantly shorter, narrowest, and smallest leaf area of comparison St. Augustinegrass cultivars. These reduced leaf characteristics result in NUF-76 appearance to be a fine leaf textured St. Augustinegrass with a dense and compact canopy. NUF-76 average leaf length measured 106.5 mm and a width of 6.7 mm. These measurements resulted in average leaf area of 62.6 square mm, 68% the area of its closest comparison variety.
TABLE 4
Measurements of leaf characteristics of NUF-76 and comparison
St. Augustinegrasses1.
Variety
Leaf Length (mm)
Leaf Width (mm)
Leaf Area (mm2)
NUF-76
106.5 d
6.7 d
62.6 d
Seville
130.2 c
8.0 c
91.7 c
FX-10
153.2 b
9.2 a
122.3 b
NUF-216
170.2 b
8.0 b
116.7 b
Floratam
204.4 a
9.0 a
154.7 a
1Means followed by the same letter are not significantly different (P = 0.05) using a protected LSD test (SAS 1996).
Reproductive Structures
Inflorescences of NUF-76 are terminal and auxiliary, averaging 1.85 panicles per flowering culm. Mean spike length of NUF-76 is 97.75 mm, equal in shortness to 1997-6 and shorter than other cultivars. Floral region measurements averaged 57.35 mm for NUF-76 which was shorter than all cultivars known to the inventor except for FX-10. Spiklet or seed number per inflorescence was 25, equal to Floratam, Seville and Raleigh for the lowest number. Stigmas are white and anther sac color is yellow.
TABLE 5
Inflorescence characteristics NUF-76 and comparison
St. Augustinegrass1.
Spike
Floral
Number of
Spike
Length
Region
Spiklets
number
Variety
(mm)
Length (mm)
(seeds)
per shoot
FX-10
120.8
de
59.0
d
39.8
a
2.3
bcd
NUF-216
161.8
a
88.6
b
36.0
a
2.8
ab
NUF-232
132.6
cd
84.4
b
30.4
b
2.7
abc
(unpatented)
1997-6
107.6
ef
71.2
c
29.5
b
2.8
a
(unpatented)
Floratam
153.4
ab
99.8
a
28.6
bc
2.1
d
Seville
121.1
de
68.6
c
21.2
d
2.2
cd
Raleigh
142.4
bc
71.3
c
21.0
d
2.2
cd
(unpatented)
NUF-76
97.8
f
57.4
d
25.0
cd
1.8
d
1Means followed by the same letter are not significantly different (P = 0.05) using a protected LSD test (SAS 1996).
TABLE 6
Anther and stigma color of NUF-76 and other comparison
St. Augustinegrass varieties1.
Variety
Anther Color
Stigma Color
NUF-76
Yellow
White
Seville
Yellow
White hairs/purple shaft
Floratam
Orange Yellow
Purple
Raleigh
Yellow
White
Bitterblue
Orange Yellow
White hairs/purple shaft
Palmetto
Orange Yellow
White
1Color as observed at pollen dehiscence.
Growth and Ground Coverage
Growth of NUF-76 lateral shoots was equal to other cultivars at 6 weeks from transplanting rooted cutting into the field. However, at 9 weeks lateral shoot lengths of NUF-76 was the shortest. Internode counts however did not differ among cultivars and reduce lateral length was attributed to shorter internodes. As a result, ground coverage during grow-in after sprigging or plugging a new field by NUF-76 was slowest for all cultivars tested. Starting with 3% coverage by the grass plug, mean coverage by NUF-76 was 27.8% after eight weeks. By 16 weeks of growth, all cultivars had 96% ground coverage or better indicating that coverage by NUF-76 will catch up to the other cultivars and coverage approach 100%.
TABLE 7
shoot length and node count of NUF-76 and comparison
St. Augustinegrass1.
Shoot length
Number of
Shoot
Number of
at 6 weeks
internodes 6
length at
internodes
Variety
(cm)
wks
9 weeks
9 weeks
NUF-76
10.1 a
4.0
ab
30.2 c
8.4 a
Seville
17.0 a
4.6
a
49.0 b
9.5 a
FX-l0
8.9 a
2.5
b
40.5 bc
7.7 a
NUF-216
16.7 a
3.8
ab
61.2 a
10.2 a
Floratam
15.9 a
4.6
a
60.6 a
10.2 a
1Means followed by the same letter are not significantly different (P = 0.05) using a protected LSD test (SAS 1996).
TABLE 8
Percentage coverage by NUF-76 and other comparison St.
Augustinegrasses. Planted Oct. 14, 2004 on 30 cm spacing1.
Percentage of Ground Cover by Turfgrass
8 weeks
12 weeks
16 weeks
Variety
Dec. 13, 2004
Jan. 19, 2005
Feb. 22, 2005
NUF-76
27.5 c
56.2 c
96.0 b
Floratam
38.8 b
83.8 b
100.0 ab
NUF-216
48.8 a
87.5 b
98.5 a
Seville
47.5 a
94.2 a
99.5 a
1Means followed by the same letter are not significantly different (P = 0.05) using a protected LSD test (SAS 1996).
Busey, Philip, Nagata, Russell T.
| Patent | Priority | Assignee | Title |
| ER3781, | |||
| ER6236, |
| Patent | Priority | Assignee | Title |
| 20090199316, | |||
| 20090293164, | |||
| PP7699, | Jul 07 1989 | University of Florida | St. Augustinegrass named `FX-33` |
| PP7852, | Mar 28 1990 | University of Florida | `FX-10`, a variety of St. Augustinegrass |
| Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
| Aug 08 2007 | Florida Foundation Seed Producers, Inc. | (assignment on the face of the patent) | / | |||
| Apr 29 2009 | NAGATA, RUSSELL T | The University of Florida Board of Trustees | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 022701 | /0533 | |
| May 07 2009 | BUSEY, PHILIP | The University of Florida Board of Trustees | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 022701 | /0533 | |
| May 12 2009 | The University of Florida Board of Trustees | FLORIDA FOUNDATION SEED PRODUCERS, INC | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 022701 | /0644 |
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