Affiliation:
1. Institute of Turfgrass Science, Beijing Forestry University, Beijing 100083, China
2. Department of Turf Science and Engineering, Sichuan Agricultural University, Chengdu 611130, China
Abstract
As a typical warm-season grass, bermudagrass growth and turf quality begin to decrease when the environmental temperature drops below 20 °C. The current study investigated the differential responses of three bermudagrass genotypes to chilling stress (8/4 °C) for 15 days and then freezing stress (2/−2 °C) for 2 days. The three genotypes exhibited significant variation in chilling and freezing tolerance, and Chuannong-3, common bermudagrass 001, and Tifdwarf were ranked as cold-tolerant, -intermediate, and -sensitive genotypes based on evaluations of chlorophyll content, the photochemical efficiency of photosystem II, oxidative damage, and cell membrane stability, respectively. Chuannong-3 achieved better tolerance through enhancing the antioxidant defense system to stabilize cell membrane and reactive oxygen species homeostasis after being subjected to chilling and freezing stresses. Chuannong-3 also downregulated the ethylene signaling pathway by improving CdCTR1 expression and suppressing the transcript levels of CdEIN3-1 and CdEIN3-2; however, it upregulated the hydrogen sulfide signaling pathway via an increase in CdISCS expression under cold stress. In addition, the molecular basis of cold tolerance could be associated with the mediation of key genes in the heat shock pathway (CdHSFA-2b, CdHSBP-1, CdHSP22, and CdHSP40) and the CdOSMOTIN in Chuannong-3 because the accumulation of stress-defensive proteins, including heat shock proteins and osmotin, plays a positive role in osmoprotection, osmotic adjustment, or the repair of denatured proteins as molecular chaperones under cold stress. The current findings give an insight into the physiological and molecular mechanisms of cold tolerance in the new cultivar Chuannong-3, which provides valuable information for turfgrass breeders and practitioners.
Funder
China Postdoctoral Science Foundation
Subject
Inorganic Chemistry,Organic Chemistry,Physical and Theoretical Chemistry,Computer Science Applications,Spectroscopy,Molecular Biology,General Medicine,Catalysis
Reference75 articles.
1. Fry, J., and Huang, B. (2004). Applied Turfgrass Science and Physiology, John Wiley Sons.
2. Hao, T., Yang, Z., Liang, J., Yu, J., and Liu, J. (2023). Foliar application of carnosine and chitosan improving drought tolerance in bermudagrass. Agronomy, 13.
3. Lipid composition remodeling plays a critical role during the differential responses of leaves and roots to heat stress in bermudagrass;Bian;Environ. Exp. Bot.,2023
4. Current knowledge of bermudagrass responses to abiotic stresses;Huang;Breeding Sci.,2019
5. Bermudagrass freezing tolerance associated with abscisic acid metabolism and dehydrin expression during cold acclimation;Zhang;J. Amer. Soc. Hort. Sci.,2008