Salt Stress-induced Injury is Associated with Hormonal Alteration in Kentucky Bluegrass

Plant hormones play an important role in plant adaptation to abiotic stress, but hormonal responses of cool-season turfgrass species to salt stress are not well documented. This study was carried out to investigate the responses of hormones to salt stress and examine if salt stress-induced injury was associated with hormonal alteration in kentucky bluegrass (KBG, Poa pratensis L.). The grass was grown in a growth chamber for 6 weeks and then subjected to salt stress (170 mm NaCl) for 28 days. Salt stress caused cell membrane damage, resulting in photosynthetic rate (Pn), chlorophyll (Chl), and turf quality decline in KBG. Salt stress increased leaf abscisic acid (ABA) and ABA/cytokinin (CK) ratio; reduced trans-zeatin riboside (ZR), isopentenyl adenosine (iPA), and indole-3-acetic acid (IAA), but did not affect gibberellin A4 (GA4). On average, salt stress reduced ZR by 67.4% and IAA by 58.6%, whereas it increased ABA by 398.5%. At the end of the experiment (day 28), turf quality, Pn, and stomatal conductance (gs) were negatively correlated with ABA and ABA/CK ratio, but positively correlated with ZR, iPA, and IAA. Electrolyte leakage (EL) was positively correlated with ABA and ABA/CK and negatively correlated with ZR, iPA, IAA, and GA4. GA4 was also positively correlated with turf quality and gs. The results of this study suggest that salt stress-induced injury of the cell membrane and photosynthetic function may be associated with hormonal alteration and imbalance in KBG.

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Responses of Tolerant and Susceptible Kentucky Bluegrass Germplasm to Salt Stress

Journal of the American Society for Horticultural Science ◽

10.21273/jashs03755-16 ◽

2016 ◽

Vol 141 (5) ◽

pp. 449-456 ◽

Cited By ~ 3

Author(s):

B. Shaun Bushman ◽

Lijun Wang ◽

Xin Dai ◽

Alpana Joshi ◽

Joseph G. Robins ◽

...

Keyword(s):

Salt Stress ◽

Antioxidant Activities ◽

Poa Pratensis ◽

Inorganic Ions ◽

Kentucky Bluegrass ◽

Western North America ◽

Turf Quality ◽

Ionic Stress ◽

Highly Correlated ◽

Eventual Death

Much of semiarid western North America is salt affected, and using turfgrasses in salty areas can be challenging. Kentucky bluegrass (Poa pratensis L.) is relatively susceptible to salt stress, showing reduced growth, osmotic and ionic stress, and eventual death at moderate or high salt concentrations. Considerable variation exists for salt tolerance among kentucky bluegrass germplasm, but gaining consistency among studies and entries has been a challenge. In this study, two novel kentucky bluegrass accessions recently reported as salt tolerant (PI 371768 and PI 440603) and two cultivars commonly used as references (Baron and Midnight) were compared for their turf quality (TQ), stomatal conductance (gS), leaf water potential (ψLEAF), electrolyte leakage (EL), and accumulation of inorganic ions under salt stress. TQ, ψLEAF, and EL were highly correlated with each other while only moderately correlated with gS. The tolerant accessions showed higher ψLEAF and lower EL than the cultivars Midnight and Baron at increasing salt concentrations and over 28 days of treatment. The accumulation of sodium (Na) and calcium (Ca) in the leaves was highly correlated and did not vary significantly among the four entries. Genes involved in ion transport across membranes, and in antioxidant activities, were significantly induced on salt stress in the tolerant accessions relative to the susceptible. These data indicate the ability of tolerant accessions to ameliorate oxidative stress and prevent EL, and confirmed the tolerance of germplasm previously reported on while indicating mechanisms by which they tolerate the salt stress.

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Drought Resistance and Recovery of Kentucky Bluegrass (Poa pratensis L.) Cultivars under Different Nitrogen Fertilisation Rates

Agronomy ◽

10.3390/agronomy11061128 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1128

Author(s):

Cristina Pornaro ◽

Michele Dal Maso ◽

Stefano Macolino

Keyword(s):

Drought Stress ◽

Poa Pratensis ◽

Recovery Period ◽

Kentucky Bluegrass ◽

Recovery Phase ◽

First Year ◽

Cool Season ◽

Nitrogen Fertilisation ◽

Turf Quality ◽

Green Cover

Kentucky bluegrass (Poa pratensis L.) is one of the most popular cool-season turfgrass species. However, little is known about the effects of N supply on its resistance to drought stress. The objective of this study was to assess the effects of acute drought followed by a recovery period on four Kentucky bluegrass cultivars (‘Barduke’, ‘Brooklawn’, ‘NuBlue Plus’ and ‘Marauder’) and one tall fescue (‘Rhambler SRP’) under two different nitrogen fertilisation rates (100 or 200 kg N ha−1 yr−1). The study was conducted over two years in a rain-out structure to control water input in spring and summer. The cultivars were subjected to a drought stress phase (absence of irrigation) followed by a recovery phase (weekly irrigation with an intake of 80% of ET). The green cover percentage, visual quality, NDVI, and soil moisture were measured weekly. We found that Kentucky bluegrass maintains sufficient turf quality for 2 weeks without irrigation. During the first year of the experiment, slight differences were observed among the Kentucky bluegrass cultivars, with ‘Marauder’ showing a 15% of green turf cover less than ‘Brooklawn’ after 6 weeks of acute drought, while in the second year, ‘NuBlue Plus’ displayed higher green turf cover and NDVI than the other cultivars. Nitrogen treatment had limited influence on the performances of the cultivars, ‘Marauder’ being the only one benefitting from the higher rate of applications.

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Growth and Physiological Factors Involved in Interspecific Variations in Drought Tolerance and Postdrought Recovery in Warm- and Cool-season Turfgrass Species

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.140.5.459 ◽

2015 ◽

Vol 140 (5) ◽

pp. 459-465 ◽

Cited By ~ 2

Author(s):

Jingjin Yu ◽

Mengxian Liu ◽

Zhimin Yang ◽

Bingru Huang

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Poa Pratensis ◽

Warm Season ◽

Kentucky Bluegrass ◽

Cool Season ◽

Physiological Factors ◽

Zoysia Matrella ◽

Turf Quality ◽

Relative Water

Drought stress is one of the most important abiotic stresses limiting plant growth, while high recuperative capacity of plants from drought damages is critical for plant survival in periods of drought stress and rewatering. The objective of our study was to determine physiological and growth factors in association with drought tolerance and recuperative capacity of cool-season kentucky bluegrass (Poa pratensis cv. Excursion II) and warm-season zoysigrass (Zoysia matrella cv. Diomand), which were grown in controlled environment chambers and maintained well watered (control) or subjected to drought stress and subsequently rewatering. Compared with kentucky bluegrass, zoysiagrass maintained higher leaf hydration level during drought stress, as shown by greater relative water content (RWC), improved osmotic adjustment (OA), increased leaf thickness, and more extensive root system at deeper soil layers. Turf quality (TQ) and photosynthesis recovered to a greater level and sooner in response to rewatering for zoysiagrass, compared with kentucky bluegrass, which could be due to more rapid reopening of stomata [higher stomatal conductance (gS)] and leaf rehydration (higher RWC). The aforementioned physiological factors associated with leaf dehydration tolerance during drought and rapid resumption in turf growth and photosynthesis in zoysiagrass could be useful traits for improving drought tolerance in turfgrasses.

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Potassium and irrigation water salinity on the formation of sour passion fruit seedlings

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v25n6p393-401 ◽

2021 ◽

Vol 25 (6) ◽

pp. 393-401

Author(s):

Geovani S. de Lima ◽

Maria G. da S. Soares ◽

Lauriane A. dos A. Soares ◽

Hans R. Gheyi ◽

Francisco W. A. Pinheiro ◽

...

Keyword(s):

Salt Stress ◽

Cell Membrane ◽

Irrigation Water ◽

Membrane Damage ◽

Passion Fruit ◽

Water Salinity ◽

Cell Membrane Damage ◽

Irrigation Water Salinity ◽

Sour Passion Fruit

HIGHLIGHTS Potassium does not attenuate the deleterious effects of salt stress on the formation of seedlings of sour passion fruit. Water salinity increases the percentage of cell membrane damage in sour passion fruit seedlings. Salt stress inhibits growth of sour passion fruit but water with up to 3.5 dS m-1 can be used for formation of its seedlings.

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Particle Size of Drug Nanocarriers Defines the Fate of Spinal Cord Injury’s Recovery

10.21203/rs.3.rs-530238/v1 ◽

2021 ◽

Author(s):

Delaram Poormoghadam ◽

Bita Rasoulian Shiadeh ◽

Fereshte Azedi ◽

Hani Tavakol ◽

Seyed Mahdi Rezayat ◽

...

Keyword(s):

Spinal Cord ◽

Cell Membrane ◽

Muscular Atrophy ◽

Muscle Tone ◽

Membrane Damage ◽

Definitive Treatment ◽

Detrusor Muscle ◽

Cell Membrane Damage ◽

Fty 720 ◽

Cord Injury

Abstract Spinal cord injury (SCI) is a debilitating condition for which no definitive treatment has yet been identified. Noteworthy, it influences other tissues through inflammatory reactions and metabolic disturbance. Therefore, fingolimod (FTY-720) as an FDA-approved inflammatory modulator would be promising. In the present study, nanocarriers at two distinct monodisperse particle sizes of 60 (nF60) and 190 (nF190) nm were prepared.The neural stem cell (NSC) viability and LDH release were studied in the face of the nanocarriers and free FTY-720. Results indicated that nanocarriers and free FTY-720 enhanced NSC viability than the control group.However, nF190 significantly induced less cell membrane damage than nF60. Nanocarriers and free FTY-720 enhanced motor neuron recovery in SCI rats, while body weight and return to bladder reflux by nF190 was significantly higher than nF60 groups. Return to bladder reflux might be due to the role of FTY-720 in regulation of detrusor muscle tone and preservation of the integrity of vessels by acting on endothelial cells. Moreover,nF190 gained higher soleus muscle weight than the free drugs;probably decreasing pro-inflammatory cytokines in soleus diminish muscular atrophy in SCI rats.To sum thing up, larger nanacarrirs with less cell membrane damage seems to be more efficient than smaller ones to manage SCI.

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Surface chemistry modification of silica nanoparticles alters the activation of monocytes

Therapeutic Delivery ◽

10.4155/tde-2021-0006 ◽

2021 ◽

Author(s):

Romina Mitarotonda ◽

Martín Saraceno ◽

Marcos Todone ◽

Exequiel Giorgi ◽

Emilio L Malchiodi ◽

...

Keyword(s):

Flow Cytometry ◽

Immune System ◽

Cell Membrane ◽

Cell Activation ◽

Membrane Damage ◽

Living Cells ◽

Cell Membrane Damage ◽

Study Materials ◽

Therapeutic Molecules ◽

Pro Inflammatory Cytokines

Aim: Nanoparticles (NPs) interaction with immune system is a growing topic of study. Materials & methods: Bare and amine grafted silica NPs effects on monocytes/macrophages cells were analyzed by flow cytometry, MTT test and LIVE/DEAD® viability/cytotoxicity assay. Results: Bare silica NPs inhibited proliferation and induced monocyte/macrophages activation (increasing CD40/CD80 expression besides pro-inflammatory cytokines and nitrite secretion). Furthermore, silica NPs increased cell membrane damage and reduced the number of living cells. In contrast, amine grafted silica NPs did not alter these parameters. Conclusion: Cell activation properties of bare silica NPs could be hindered after grafting with amine moieties. This strategy is useful to tune the immune system stimulation by NPs or to design NPs suitable to transport therapeutic molecules.

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