Registration of ‘ MSA 2-3-98 ’ St . Augustinegrass

‘MSA 2-3-98’ (Reg. No. CV-284, PI 689102) is a cold-tolerant, high-quality St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] developed at Mississippi State University. MSA 2-3-98 was released on 19 Apr. 2006 from Mississippi Agricultural and Forestry Experiment Station. MSA 2-398 offers many advantages compared with other St. Augustinegrass cultivars. Leaf length, leaf width, internode length, and internode diameter of MSA 2-3-98 were significantly smaller than ‘Floratam’ and ‘Raleigh’. The more diminutive morphology of MSA 2-3-98 allows it to establish a denser turfgrass canopy with finer leaf texture. Cold tolerance of MSA 2-3-98 was evaluated from spring assessments of percentage green turfgrass cover and overall plot green-up. The cold tolerance of MSA 2-3-98 was similar to Raleigh but outperformed Floratam. MSA 2-3-98 turfgrass quality tended to be greater than ‘Delmar’, Floratam, and Raleigh. Gray leaf spot severity on MSA 2-3-98 was variable among locations where the disease was evaluated. MSA 2-3-98 has greater turfgrass quality than Raleigh, with similar cold tolerance.

S t.Augustinegrass [Stenotaphrum secundatum   (Walt.)Kuntze] is a desirable warm-season turfgrass commonly established in tropical and subtropical climates (Sauer, 1972).Its primary use is for home lawns due to its moderate shade tolerance (Trenholm and Nagata, 2005), coarse leaf texture, and poor traffic tolerance (Hanna et al., 2013).The establishment of St. Augustinegrass in temperate climates, however, is hindered by its poor cold tolerance and winter survivability, although its cold tolerance can be increased from breeding and selection (Philley et al., 1998).As part of the effort to increase winter survivability of St. Augustinegrass, 'MSA 2-3-98' (Reg.No. CV-284, PI 689102), a cold-tolerant St. Augustinegrass with desirable turfgrass quality, was developed at Mississippi State University (MSU).

Morphology
Morphological characteristics of internode length, internode diameter, leaf length, and leaf width were measured on 'Floratam ', MSA 2-3-98, 'MSA-31', and Raleigh. In March 2006, five samples (10.2 cm diam.) of each cultivar were harvested from field establishments at the MSU R.R. Foil Plant Science Research Center (Starkville, MS).The samples were then washed and transplanted into a soilless sphagnum peat-based growing medium.Samples were left unmown in greenhouse culture at MSU for 6 wk prior to measurements.Internode length and diameter were measured on the third internode counting from the youngest identifiable internode backward to the center of the pot.Internode diameter was measured on the internode lateral aspect.Leaf length and width were measured on all leaves as stolons emerged and expanded.Measurements were made using dial calipers (SPI 2000;Swiss Precision Instruments).
All morphological data were subjected to analysis of variance using SAS 6.03 (SAS Institute, 1988) with main effect of genotype in a completely randomized design.Means of significant genotype effects (a = 0.05) were separated using Fisher's protected LSD.Turfgrass quality, percentage green turfgrass cover, gray leaf spot (caused by Pyricularia oryzae Cavara) severity, and spring green-up were visually assessed according to NTEP guidelines (Morris and Shearman, n.d.).Percentage green turfgrass cover and spring green-up were used to evaluate the cold tolerance of MSA 2-3-98 and the other St. Augustinegrasses.All experiments used a randomized complete block design with three replications.Turfgrass performance data were subjected to analysis of variance using SAS 6.03 (SAS Institute, 1988) with main effect of genotype.Analysis of variance was performed separately for each assessment year for the Starkville, MS (non-NTEP), and Lawrenceburg, TN, evaluations.However, ANOVA was performed on each separate NTEP location averaged from 2003 to 2006.Means of significant effects were separated using Fisher's protected LSD (a = 0.05).

Morphology
Morphology measurements are presented in Table 1.Mean leaf length and width for MSA 2-3-98 were in the lowest statistical grouping, significantly smaller than commercial cultivars Floratam and Raleigh (Table 1).Mean internode length for MSA 2-3-98 was similar to MSA 31 but significantly shorter than Floratam and Raleigh.Internode diameter for MSA 2-3-98 was not in the lowest grouping but remained significantly smaller than Floratam and Raleigh (Table 1).The more diminutive morphology of MSA 2-3-98 describes its texture and contributes to a denser turfgrass canopy compared with Floratam and Raleigh.

Cold Tolerance
Tables 2 to 5 show percentage green cover and spring greenup ratings to compare cold tolerance among the St. Augustinegrasses.Percentage cover of MSA 2-3-98 in Lawrenceburg, TN, and Starkville, MS, was similar to Raleigh but significantly greater than Floratam in four of five assessment years (Table 2).In the NTEP test, MSA 2-3-98 percentage cover was in the top statistical grouping when genotype was significantly different (Table 3).Spring green-up ratings for MSA 2-3-98 in Starkville were significantly greater than Floratam in all 5 yr but only significantly greater than Raleigh in 2000 (Table 4).Spring greenup of MSA 2-3-98 in the NTEP test was in the top statistical grouping at four of eight locations.However, three of the four locations were the northernmost NTEP locations (Table 5).

Turfgrass Performance
Visual turfgrass quality and gray leaf spot severity evaluations are presented in Tables 6 to 10. Yearly mean quality of MSA 2-3-98 in Starkville (non-NTEP) was significantly greater than Floratam in 2000 to 2005 and greater than Raleigh in 2000, 2004, and 2005 (Table 6 (Table 6).In Lawrenceburg, MSA 2-3-98 turfgrass quality was significantly greater than Floratam and similar to Raleigh in 2002 to 2005 (Table 7).In addition, MSA 2-3-98 mean visual turfgrass quality was in the top grouping in seven of the eight NTEP locations from 2003 to 2006 (Table 8).

Availability
MSA 2-3-98 is protected by US Patent No. PP21,240 P3 (Philley and Krans, 2010).Mississippi Agricultural and Forestry Experiment Station will maintain breeder and foundation stock of MSA 2-3-98 at MSU. MSA 2-3-98 may only be produced by licensed growers using Mississippi Crop Improvement Association guidelines.Contact the MSU Office of Technology Management (http://www.oett.msstate.edu/)for more information regarding licensing of MSA 2-3-98.A sample of MSA 2-3-98 has been deposited into the USDA-ARS National Laboratory for Genetic Resources Preservation, where it will be available for distribution immediately upon request from the date of this publication.

Conclusions
MSA 2-3-98 offers many advantages compared with other St. Augustinegrass cultivars.Leaf length, leaf width, internode length, and internode diameter of MSA 2-3-98 were significantly smaller than Floratam and Raleigh.The more diminutive morphology of MSA 2-3-98 allows it to establish a denser turfgrass canopy with finer leaf texture.Cold tolerance of MSA 2-3-98 was evaluated from spring assessments of percentage green turfgrass cover and overall plot green-up.The cold tolerance of MSA 2-3-98 was similar to Raleigh, but MSA 2-3-98 outperformed Floratam.MSA 2-3-98 turfgrass quality tended to be greater than Delmar, Floratam, and Raleigh.Gray leaf spot severity on MSA 2-3-98 was variable among locations where the disease was evaluated.MSA 2-3-98 has greater turfgrass quality than Raleigh, with similar cold tolerance.2.1 1.0 1.0 † Disease severity was assessed on a 1-to-9 scale, where 1 = severe and 9 = disease free.
F2 selections and allowed to open pollinate.MSA 2-3-98 is a single genotype selection that resulted from the open-(possible self-) pollination of F2-1.MSA 2-3-98 was evaluated and released on 19 Apr.2006 from Mississippi Agricultural and Forestry Experiment Station.

Table 1 . Internode length, internode diameter, leaf length, and leaf width of Floratam, MSA 2-3-98, MSA-31, and Raleigh St. Augustinegrass unmown in greenhouse culture at Mississippi State University (Starkville, MS).
Internode length and diameter were measured on the third internode counting from the youngest identifiable internode backward to the center of the pot.‡ Measurements were made on all leaves as stolons emerged and expanded.

Table 8 . Mean visual turfgrass quality from 2003 to 2006 of six St. Augustinegrasses established in 2002 at eight locations for the National Turfgrass Evaluation Program.
Turfgrass quality was assessed on a 1-to-9 scale, where 1 = poorest quality and 9 = highest quality.