Evaluation of Lolium temulentum as a model grass species for the study of salinity stress by PCR-based subtractive suppression hybridization analysis

Salinity is a detrimental abiotic stress for plant growth in salt-affected soils. The objective of this study was to examine photosynthetic responses to salinity stress in two warm-season turfgrasses differing in salinity tolerance. Salt-tolerant species seashore paspalum (Paspalum vaginatum) and salt-sensitive species centipedegrass (Eremochloa ophiuroides) were exposed to salinity at three NaCl concentrations (0, 300, and 500 mm) in a growth chamber. Turf quality, relative water content (RWC), and leaf photochemical efficiency (Fv/Fm) declined, whereas electrolyte leakage (EL) increased under the two NaCl regimes for both grass species, and the changes were more dramatic in centipedegrass than that in seashore paspalum as well as in the higher salinity concentration. Two grass species showed different phytosynthetic responses to salinity stress. The earlier inhibition of photosynthesis in seashore paspalum was mainly associated with stomatal closure. As salinity increased and salinity stress prolonged, the inhibition of photosynthesis in seashore paspalum was mainly associated with non-stomatal factors. The inhibition of photosynthesis in centipedegrass was associated with both stomatal closure and non-stomatal factors at both salinity levels. The sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) analysis demonstrated the Rubisco large subunit had no obvious decrease during the whole stress period under the 300-mm and 500-mm treatments in seashore paspalum, whereas it significantly decreased in centipedegrass under both the 300-mm and 500-mm treatments. The results indicated that the superior salinity tolerance in seashore paspalum, compared with centipedegrass, could be attributed to its maintenance of Rubisco stability, chlorophyll content, photochemical efficiency as well as photosynthetic rate (Pn) capacity under salinity stress.

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Transcriptome Analysis of Wounding in the Model Grass Lolium temulentum

Plants ◽

10.3390/plants9060780 ◽

2020 ◽

Vol 9 (6) ◽

pp. 780

Author(s):

James E. Dombrowski ◽

Brent A. Kronmiller ◽

Vicky Hollenbeck ◽

Ruth C. Martin

Keyword(s):

Transcriptome Analysis ◽

Proteinase Inhibitors ◽

Wrky Transcription Factors ◽

Lolium Temulentum ◽

Mitogen Activated Protein ◽

Hormone Biosynthesis ◽

Model Grass ◽

Molecular Components ◽

Rapid Regrowth

For forage and turf grasses, wounding is a predominant stress that often results in extensive loss of vegetative tissues followed by rapid regrowth. Currently, little is known concerning the perception, signaling, or molecular responses associated with wound stress in forage- and turf-related grasses. A transcriptome analysis of Lolium temulentum plants subjected to severe wounding revealed 9413 upregulated and 7704 downregulated, distinct, differentially expressed genes (DEGs). Categories related to signaling, transcription, and response to stimuli were enriched in the upregulated DEGs. Specifically, sequences annotated as enzymes involved in hormone biosynthesis/action and cell wall modifications, mitogen-activated protein kinases, WRKY transcription factors, proteinase inhibitors, and pathogen defense-related DEGs were identified. Surprisingly, DEGs related to heat shock and chaperones were more prevalent in the downregulated DEGs when compared with the upregulated DEGs. This wound transcriptome analysis is the first step in identifying the molecular components and pathways used by grasses in response to wounding. The information gained from the analysis will provide a valuable molecular resource that will be used to develop approaches that can improve the recovery, regrowth, and long-term fitness of forage and turf grasses before/after cutting or grazing.

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Conserved microRNAs and their targets in model grass species Brachypodium distachyon

Planta ◽

10.1007/s00425-009-0974-7 ◽

2009 ◽

Vol 230 (4) ◽

pp. 659-669 ◽

Cited By ~ 88

Author(s):

Turgay Unver ◽

Hikmet Budak

Keyword(s):

Brachypodium Distachyon ◽

Grass Species ◽

Model Grass

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Differential Effects of Abscisic Acid and Glycine Betaine on Physiological Responses to Drought and Salinity Stress for Two Perennial Grass Species

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.137.2.96 ◽

2012 ◽

Vol 137 (2) ◽

pp. 96-106 ◽

Cited By ~ 19

Author(s):

Zhimin Yang ◽

Jingjin Yu ◽

Emily Merewitz ◽

Bingru Huang

Keyword(s):

Abscisic Acid ◽

Salinity Stress ◽

Glycine Betaine ◽

Foliar Application ◽

Poa Pratensis ◽

Kentucky Bluegrass ◽

Grass Species ◽

Antioxidant Metabolism ◽

Positive Effects ◽

Turf Quality

Abscisic acid (ABA) and glycine betaine (GB) may regulate plant responses to drought or salinity stress. The objectives of this controlled-environment study were to determine whether foliar application of ABA or GB improves turf quality under drought or salinity and whether improved stress responses were associated changes in antioxidant metabolism in two C3 turfgrass species, creeping bentgrass (Agrostis stolonifera) and kentucky bluegrass (Poa pratensis). Physiological parameters evaluated included turf quality, leaf relative water content, membrane electrolyte leakage (EL), membrane lipid peroxidation [expressed as malondialdehyde (MDA) content], and activity of superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX). Abscisic acid and GB were both effective in mitigating physiological damage resulting from drought or salinity for both grass species, but effects were more pronounced on kentucky bluegrass. The most notable effects of ABA or GB application were the suppression of EL and MDA accumulation and an increase in APX, POD, and SOD activities after prolonged periods of drought (21 days) or salinity stress (35 days). These results suggest foliar application of ABA or GB may alleviate physiological damage by drought or salinity stress in turfgrass and the maintenance of membrane stability and active antioxidant metabolism could contribute to the positive effects in the stress mitigation effects.

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