With goals in place, TAMU started working on crosses between selected St. Augustine experimental lines. After many years of cross pollination, work done in laboratories and initial screening, a group of eight elite varieties were selected based on their performance at several test areas in Texas and across the Southeastern US:
- DALSA 1318
- DALSA 1329
- DALSA 1404
- DALSA 1405
- DALSA 1406
- DALSA 1502
- DALSA 1618
These experimental lines were planted at two sod farms: Kubicek Farms (South Texas) and A-1 Turf Farm (North Texas) in June and July 2018. These eight elite lines were planted initially in 5-by-10 foot plots, which later were extended to 20 feet long. This layout was designed by TAMU in collaboration with Sod Solutions. The “long plot” was developed after realizing that a good candidate for the market needs to harvest well. Quality harvesting can only be identified by growing the grass in a layout that allows a regular sod harvester to easily access and harvest the sod. All eight elite lines were evaluated for disease resistance, genetic color, overall quality and drought resistance. The grasses were harvested three times—in May 2019, August 2019 and July 2020—while tensile strength was evaluated with a device developed by TAMU. A group of producers were present during the harvesting to help identify the best grasses and make additional evaluations. Dr. Ambika Chandra was the lead breeder coordinating the testing along with Dr. Chrissie Segars (TAMU) and Roberto Gurgel (SS).
Once all varieties were harvested and tested, the data was compiled and analyzed. After years of observation, four advanced lines have been selected based on their final evaluations for sod quality: • DALSA 1318 • DALSA 1329 • DALSA 1404 • DALSA 1618 These final four varieties were expanded and planted in a new area (July 2020). Planting was performed with a commercial plug planter and each plot covered a much larger area, ranging from 12,000 to 20,000 square feet. The larger areas were designed to also provide plant stock material for a foundation block.
After one year of growth, the final four selections were compared using performance data from the larger plots combined with data from the 2015 USDA-SCRI research group, the 2016 NTEP trials and a shade and drought tolerance trial collected at the Dallas Agri-Life Center. DALSA 1618 was the final selection and was designated the name Cobalt™ Hybrid St. Augustine.
Cobalt is an ERT (Embryo Rescue Technology) interploid hybrid; a grass with excellent drought resistance, very good shade tolerance, is tolerant of disease, has a good establishment rate and is winter hardy. This selection has an excellent visual quality with a dark green genetic color and a wide leaf blade and stolon.
A second experimental grass from that final group of four varieties—DALSA 1318—is going to be evaluated for a couple more years as it demonstrates an excellent establishment ratio that grows-in faster than any other grass including 1618. However, it is a diploid and does not have the same level of drought or shade tolerance as 1618. A 10-acre foundation block of DALSA 1618 was planted the first week of September 2021, using the plant material grown over the last 13 months.
For more information about Cobalt click here.