Sod Production Characteristics of Advanced Bermudagrass Lines Having Improved Drought Resistance.

Suitable sod tensile strength (STS) and sod handling quality (SHQ) are two of many important production traits needed in future improved turfgrass cultivar releases. Advanced turf-type bermudagrass lines previously determined to demonstrate delayed leaf firing under drought conditions were evaluated for STS and SHQ in the summer of 2017 at Stillwater, OK. Twenty-three and 20 advanced bermudagrass lines from the Oklahoma State University and the University of Georgia turfgrass breeding programs were evaluated in this research. The commercialized cultivars 'Celebration,' 'TifTuf,' 'Latitude 36' and 'Tifway' were included as standards for comparative purposes. The stock blocks planted in 2016 as well as replicated field trial in 2017 were conducted at Stillwater, OK. Sod tensile strength and handling quality were determined under simulated commercial production conditions in the field. To assess SHQ and STS two sod pads, each measuring 0.38 m x 0.305 m x 0.15 m (length x width x depth), were cut from each replicate. The SHQ of each entry was assessed on a 1 to 5 visual scale where 1= very poor SHQ and 5=excellent SHQ. The STS was measured as the peak force required to cause sod pad tearing using an electric actuator and force transducer/recorder system. Preliminary findings indicate that several experimental lines from both breeding programs compared very favorably with current commercialized standards. Additional production/harvest testing will be conducted in the future. Knowledge of the sod production characteristics of promising lines will further aid the turfgrass breeder in making decisions concerning advancement of a smaller number of lines towards national trials where further genotype x environment testing will occur. This work was conducted under USDA-NIFA Specialty Crops Research Initiative Grant Number 2015-51181-24291.