Tall Fescue and Bermudagrass Cultivar Response to Water Stress at the Germination Growth Stage

Abstract

Examining and developing screening techniques to identify drought‐resistant lines at the seedling stage is an important step for plant breeders. Therefore, the objectives of this research trial were to determine if the use of polyethylene glycol (PEG‐6000) is an effective tool to screen for water stress during seed germination and to determine potential cultivar differences within each species tested. Bermudagrass [Cynodon dactylon (L.) Pers.] cultivars selected included ‘Hollywood’, ‘Northshore’, ‘Riviera’, and ‘Transcontinental’. Tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.] cultivars included ‘Jaguar 4G’, ‘Quest’, ‘Summer’, and ‘Sundial’ as well as four experimental cultivars. Water stress levels were developed using PEG‐6000. For bermudagrass, seed was subjected to 0 (control), −2.5, −5.0, −7.5, and −10.0 MPa, while tall fescue water‐stress treatments included 0 (control), −2.0, −4.0, −5.0, and −7.0 MPa. Bermudagrass and tall fescue relative final germination rate (FGR) and relative daily germination rate (DGR) decreased with increasing concentrations of PEG‐6000. Regression analysis indicated that Sundial (−6.51 MPa) and Summer (−6.09 MPa) tall fescue and Transcontinental (−4.74 MPa) and Hollywood (−4.62 MPa) bermudagrass had the highest PEG concentration to reduce relative FGR by 50%. Results suggest PEG‐6000 is an effective technique for screening turfgrass cultivars that require less water for seed germination. This study also identified cultivars that would have a competitive advantage during the establishment phase if water is a limiting factor.