PEG-induced Drought Stress in Plants: A Review

Author(s):  
Shreyas Rajeswar ◽  
Narasimhan S

Drought is one of the most commonly faced significant factors that impede plant productivity and growth. Especially in the context of agriculture, crop productivity and sustainable farming are most adversely affected by water shortage conditions caused by drought. Plants have several adaptations to respond to such conditions, both physiological as well as metabolic. An understanding of these adaptations is essential to develop a biotechnological solution to the problem of drought-related crop losses across the globe. This review addresses the various changes that plants undergo when subjected PEG (Polyethylene glycol). Various drought stress markers are associated with PEG induced stress are expressed in the biochemistry, physiology, photosynthesis and metabolism of the plant. Therefore PEG treatment in plants are considered as an effective model for drought stress investigation.

Biomolecules ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1231
Author(s):  
Tatiana N. Arkhipova ◽  
Nina V. Evseeva ◽  
Oksana V. Tkachenko ◽  
Gennady L. Burygin ◽  
Lidiya B. Vysotskaya ◽  
...  

Water deficits inhibit plant growth and decrease crop productivity. Remedies are needed to counter this increasingly urgent problem in practical farming. One possible approach is to utilize rhizobacteria known to increase plant resistance to abiotic and other stresses. We therefore studied the effects of inoculating the culture medium of potato microplants grown in vitro with Azospirillum brasilense Sp245 or Ochrobactrum cytisi IPA7.2. Growth and hormone content of the plants were evaluated under stress-free conditions and under a water deficit imposed with polyethylene glycol (PEG 6000). Inoculation with either bacterium promoted the growth in terms of leaf mass accumulation. The effects were associated with increased concentrations of auxin and cytokinin hormones in the leaves and stems and with suppression of an increase in the leaf abscisic acid that PEG treatment otherwise promoted in the potato microplants. O. cytisi IPA7.2 had a greater growth-stimulating effect than A. brasilense Sp245 on stressed plants, while A. brasilense Sp245 was more effective in unstressed plants. The effects were likely to be the result of changes to the plant’s hormonal balance brought about by the bacteria.


2018 ◽  
Vol 7 (2) ◽  
Author(s):  
Made Pharmawati ◽  
Ni Nyoman Wirasiti ◽  
Luh Putu Wrasiati

Abstrak Cekaman kekeringan merupakan faktor pembatas penting bagi pertumbuhan dan produktivitas tanaman termasuk padi.      Penelitian ini bertujuan menganalisis respon padi IR64 terhadap cekaman kekeringan dengan pemberian polietilen glikol (PEG) pada fase reproduktif.  Penelitian juga bertujuan menganalisis ekspresi gen aquaporin akibat cekaman kekeringan.  Bibit padi ditanam dalam pot dan perlakuan PEG dengan konsentrasi 108g/L (-0.25MPa) dan 178g/L (-0.52 MPa) diberikan saat munculnya panikula. Perlakuan diberikan selama 2 minggu, kemudian tanaman disiram kembali.  Ekspresi gen diamati pada akhir perlakuan dengan semi kuantitatif real time PCR.  Ekstraksi RNA menggunakan RNeasy plant mini kit, sedangkan sintesis cDNA menggunakan Transcriptor First Strand cDNA Kit.  Hasil penelitian menunjukkan bahwa jumlah malai dan berat total malai berkurang akibat cekaman kekeringan.  Persentase gabah kosong mencapai 84,6% pada perlakuan PEG-0,52 MPa, sedangkan pada perlakuan PEG -0,25 MPa persentase gabah kosong sebesar 67,8%.  Pada kontrol persentase gabah kosong adalah 10,3%.  Ekspresi gen OsPIP2;7 sedikit menurun pada perlakuan PEG -0,52 MPa.Kata kunci: ekspresi gen, IR64, kekeringan, padi, PEG  Abstract Drought stress is one of the limiting factors of plant growth and productivity including rice.  The aim of this study was to analyze responses of IR64 rice to polyethylene glycol (PEG)-induced-drought stress at the reproductive stage.  This study also aimed to analyze the expression of aquaporin under drought stress.  Rice seedlings were grown in pot system and PEG treatment at concentration of -0.25MPa (108g/L) and -0.52 MPa (178g/L) were given when the panicles arose.  Treatments were conducted for 2 weeks, after that the plants were rewatered.  Gene expression was evaluated at the end of PEG treatment using semi quantitative real time PCR. RNA was extracted using RNeasy plant mini kit, while cDNA synthesis was done using Transcriptor First Strand cDNA Kit.  The results showed that the number and weight of rice ear were less in plant treated with PEG than in control.  The percentage of empty rice grain reached 84.6% at PEG -0.52 MPa, while at PEG -0.25 MPa the percentage of empty grain was 67.8%.  In control plant, the percentage of empty grain was 10.3%.  Drought stress did not alter the expression of OsPIP2;7.  Keywords: drought, gene expression, IR64, PEG, rice


Author(s):  
Kartika Kartika ◽  
Benyamin Lakitan ◽  
Rofiqoh Purnama Ria

Drought stress during vegetative and/or generative stages could cause massive reduction in rice yield. This study evaluated effectiveness of hydro- and osmo-priming on improving seed germination, growth and development of upland rice under drought stress during late vegetative, booting, or heading stage. Treatments consisted of hydro-priming and osmo-priming consisted of three polyethylene glycol (PEG) concentrations i.e. 10%, 15%, and 20%. Results showed that application of osmo-priming at 10% PEG required longer time (21.93 hours) to reach 50% germination, lower germination and lower vigor index. However, after germination, seeds primed with 10% PEG exhibited better seedling growth than other seed priming treatments. Effects of seed priming on yield components were overshadowed by drought exposures. Drought imposed during vegetative stage did not significantly affect yield; however, regardless of seed priming treatments, yield reduction was inevitable in rice plants exposed to drought during booting or heading stages. Rice plant shortened time to reached physiological maturity as an adaptive mechanism if drought treatment was applied during heading stage. Keywords: Germination, Polyethylene glycol, Seedling growth, Seed priming, Yield component


Agronomy ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1689
Author(s):  
Zuzana Kovalikova ◽  
Petra Jiroutova ◽  
Jakub Toman ◽  
Dominika Dobrovolna ◽  
Lenka Drbohlavova

Drought stress is a serious threat. Therefore, improvements in crop productivity under conditions of limited water availability are vital to keep global food security. Apples and cherries belong to the most produced fruit worldwide. Thus, searching for their tolerant or resistant cultivars is beneficial for crop breeders to produce more resistant plants. We studied five apple (“Malinové holovouské”, “Fragrance”, “Rubinstep”, “Idared”, “Car Alexander”) and five cherry (“Regina”, “Napoleonova”, “Kaštánka”, “Sunburst”, “P-HL-C”) cultivars for their adaptation in response to progressive drought stress. The reaction of an in vitro culture to osmotic stress simulated by increasing polyethylene glycol (PEG) concentration in medium was evaluated through the morphological (fresh and dry weight, water content, leaf area), physiological (chlorophyll and carotenoids content), and biochemical (reactive oxygen species and malondialdehyde content) parameters. Drought-like stress negatively affected the water content, leaf areas, and chlorophyll content in both fruit species. Oxidative status and membrane damage of plants under water deficiency conditions occurred to be important indicators of stress tolerance mechanism. Cherries exhibited higher hydrogen peroxide levels compared to apples, whereas their malondialdehyde values were generally lower. The overall results indicated wide tolerance range to water deficit among apple and cherry in vitro culture as well as among cultivars within single plant species.


2018 ◽  
Vol 44 (4) ◽  
pp. 551-556
Author(s):  
Hua Zhao ◽  
Huiping Dai

Effects of drought stress were induced by polyethylene glycol (PEG-6000) (10, 20, and 30% ) for 2, 4, 6 and 8 days in Apocynum venetum L. seedlings with the potting method. The results showed that PEG significantly increased the activities of glutathione reductase (GR), superoxide dismutase (SOD), ascorbate peroxidase (APX), and the contents of electrolyte leakage rates, MDA, proline and soluble sugar were increased from 30% PEG. Thus, it was indicated that the application of exogenous 30% PEG induced oxidative damage by enhancing antioxidant defense systems.


2020 ◽  
pp. 1-14
Author(s):  
Mohammadreza Asghari ◽  
Feridoun Ahmadi ◽  
Ramin Hajitagilou

BACKGROUND: For global water shortage concerns and high cost of mineral nutrients it is necessary to decrease the amount of nutrient solutions in greenhouse production systems. Deficit fertigation may negatively affect the crop productivity and phytohormones can mitigate the adverse effects of stresses. OBJECTIVE: We studied the effects of deficit fertigation in combination with salicylic acid (SA) and putrescine (PUT) on strawberry fruit yield and quality. METHODS: Strawberry plants were fertilized with a complete nutrient solution of 220 (control), 180 (mild deficit fertigation) and/or 140 mL/dD (severe deficit fertigation), and treated with PUT (at 0 and 2 mM) and/or SA (at 0 and 2 mM) and the combinations of these treatments during growth stages. Fruit growth, quality parameters, yield and phytochemical compounds were evaluated at harvest. RESULTS: Mild deficit fertigation (MDF) (140 mL/d) significantly enhanced the yield and quality of the fruit, and both PUT and SA, enhanced the positive effects of MDF on crop productivity. SA and PUT decreased the negative effects of DF on crop yield and fruit growth. CONCLUSIONS: The results of this study indicate that it is possible to substantially enhance the quality and productivity of strawberries with a MDF regime, and PUT and SA treatments.


Agronomy ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 833 ◽  
Author(s):  
Barbara Tokarz ◽  
Tomasz Wójtowicz ◽  
Wojciech Makowski ◽  
Roman J. Jędrzejczyk ◽  
Krzysztof M. Tokarz

Understanding the mechanisms of plant tolerance to osmotic and chemical stress is fundamental to maintaining high crop productivity. Soil drought often occurs in combination with physiological drought, which causes chemical stress due to high concentrations of ions. Hence, it is often assumed that the acclimatization of plants to salinity and drought follows the same mechanisms. Grass pea (Lathyrus sativus L.) is a legume plant with extraordinary tolerance to severe drought and moderate salinity. The aim of the presented study was to compare acclimatization strategies of grass pea seedlings to osmotic (PEG) and chemical (NaCl) stress on a physiological level. Concentrations of NaCl and PEG were adjusted to create an osmotic potential of a medium at the level of 0.0, −0.45 and −0.65 MPa. The seedlings on the media with PEG were much smaller than those growing in the presence of NaCl, but had a significantly higher content percentage of dry weight. Moreover, the stressors triggered different accumulation patterns of phenolic compounds, soluble and insoluble sugars, proline and β-N-oxalyl-L-α,β-diamino propionic acid, as well as peroxidase and catalase activity. Our results showed that drought stress induced a resistance mechanism consisting of growth rate limitation in favor of osmotic adjustment, while salinity stress induced primarily the mechanisms of efficient compartmentation of harmful ions in the roots and shoots. Furthermore, our results indicated that grass pea plants differed in their response to drought and salinity from the very beginning of stress occurrence.


Sign in / Sign up

Export Citation Format

Share Document