Accumulation of polyethylene glycol 6000 and its effects on water content and carbohydrate level in water-stressed tomato plants

1988 ◽  
Vol 66 (5) ◽  
pp. 970-973 ◽  
Author(s):  
E. Jacomini ◽  
A. Bertani ◽  
S. Mapelli

Young tomato plants were grown in 10 or 25% polyethylene glycol (PEG) 6000 solutions to impose water stress. Plant organs were analyzed to ascertain whether the various plant parts accumulated PEG and to determine the physiological effects. PEG 6000 was taken up by tomato roots and translocated to the shoots. PEG accumulation was greater in roots and in the first leaves and negligible in apical leaves. In all leaves there was an increase in soluble-sugar concentration during the PEG treatment. However, PEG-accumulating leaves showed a delay in dehydration in comparison with leaves where PEG was not accumulated. To explain this behaviour we hypothesize that PEG was accumulated in extracellular spaces and that, as a consequence, water was drawn out from the cells, inducing cellular but not tissue dehydration.

1969 ◽  
Vol 47 (11) ◽  
pp. 1761-1764 ◽  
Author(s):  
Merrill R. Kaufmann

The effect of nearly constant water potential on germination of citrus, sunflower, and lettuce seeds was studied. Water potential equilibration was achieved by placing soil above a cellulose acetate membrane which was in contact with a solution of polyethylene glycol-6000. Selection of solute potentials in the solution resulted in controlled water potentials in the soil over a range of 0 to −14.9 bars for citrus and 0 to −8.0 bars for sunflower and lettuce. The water stress experienced by germinating seeds in this system is largely the result of a matric effect rather than a solute effect.Citrus seeds germinated at water potentials as low as −4.7 bars and lettuce at −4.1 bars, but sunflower germinated at −8.0 bars. Sunflower germinated as rapidly at −4.1 bars as lettuce at −2.3 bars, both reaching 50% germination at about 8 days. Citrus germinated much more slowly, requiring 26 days at 0 bars.


2014 ◽  
Vol 68 (1) ◽  
pp. 39-54 ◽  
Author(s):  
Parvin Salehi Shanjani ◽  
Masoumeh Izadpanah ◽  
Mohamad Reza Mohamadpour

ABSTRACT The effects of water potential on germination were studied in 18 wild populations of three yarrow species (Achillea tenuifolia, A. vermicularis and A. filipendulina) from different bioclimatic zones in Iran. Water potential between 0 and -0.6 MPa were obtained using polyethylene glycol 6000 (PEG-6000) solutions. The study of water stress on germination showed that, regardless of the species and the populations, the lowering of the water potential reduced the capacity for germination and early seeding growth. These results indicated a strong genetic potential for drought tolerance during germination within each species. These differences in germination ability of wild populations of each species might be attributed to intraspecific variations resulting from the effects of natural selection and genetic pool background.


2010 ◽  
Vol 2 (4) ◽  
pp. 59-63 ◽  
Author(s):  
Hossein Reza ROUHI ◽  
Reza Tavakkol AFSHARI ◽  
Seyed Amir MOOSAVI ◽  
Mohammad Hossain GHARINEH

Previous studies suggested that fast and uniform germination is important for good crop establishment. The present study was conducted to investigate the possibility of increasing germination characteristics by seed priming techniques. An experiment was conducted with three replicates and two treatments including: 2 different priming duration (8 and 12 hours) and 6 osmotic potential of PEG 6000 solutions (-0.8, -1,-1.2,-1.4,-1.6 Mpa) and distilled water as a control group). The priming solutions were prepared using polyethylene glycol 6000 (PEG). Our results showed that the most effective osmotic potential in improving germination characteristics of Trifolium alexandrium is -0.8 MPa for 16 hours.


Author(s):  
V. Singh ◽  
M. Sharma ◽  
H. Upadhyay ◽  
A. Siddique

An experiment was carried out to evaluate the effect of seed priming with magnesium nitrate salt against the moisture stress condition induced by Polyethylene glycol-6000 on seed germination, vigour index and tolerance index in root and shoot. Polyethylene glycol-6000 was used to create short term moisture stress under laboratory conditions while the seed priming was carried out by using magnesium nitrate. The percent germination, seed vigour index and tolerance index were started to decline from T1 to T4 (i.e. set first 1.5 and 4.5 % of PEG-6000 solution + none primed seed) while the results of second set (i.e. PEG-6000 + primed seed from T5 to T8) were also following the same decreasing trend along with improvement in every parameters. The germination was recorded highest 100 percent in T5 (i.e. 1.5% PEG-6000+ primed seed) followed by T6, T1 and T7 (T6 and T7 is 2.5% and 3.5 % PEG-6000+ primed seed) while the control set recorded 98.7% at final date of observations i.e. 240 Hrs. vigour index and tolerance index was also decreasing in both the set of treatments but PEG-600 + primed seed showed better results as compared to the treatments PEG-6000 + none primed. Tolerance index percent was recorded maximum in root as compare to shoot at 120 hrs. of intervals while the reverse result was recorded at 240 hrs. of intervals.


2021 ◽  
Vol 15 (1) ◽  
pp. 12-25
Author(s):  
Tokpapon Eliane Manlé ◽  
Kan Modeste Kouassi ◽  
Brahima André Soumahoro ◽  
Tchoa Koné ◽  
Kouablan Edmond Koffi ◽  
...  

Rainfall scarcity due to climate change is a major constraint that limits cocoa productivity in Côte d'Ivoire. This work aims to regenerate cocoa plants tolerant to water stress using in vitro methods. Staminode and petal explants of the genotypes C1, C9, C14, C15, C16, C18 and C20 were used to produce somatic embryos through two methods. Firstly, somatic embryos were induced under stressfull conditions on media containing different concentrations of polyethylene glycol (PEG) 6000 (0; 25; 50; 75; 100 and 125 g/l) and secondly; under non-stressed conditions. Somatic embryos were placed on a conversion medium in the same stress condition. The number of regenerants decreased with the increase in the concentration of PEG with all genotypes. Only genotypes C1 and C15 regenerated plantlets under water stress conditions. The sensitive genotypes C9, C14, C16, C18 and C20 have not developed plantlets on media containing PEG. The plantlets produced under water deficit conditions exhibited a reduction in stem length and leaves number and an increase in length or offset of the high number of roots. The survival rate of regenerants during acclimatization was higher on the sandsubstrate. The selected genotypes could be used in an improvement program of cocoa production.Keywords: Climate change; plant regeneration; genotype; tolerance; drought; in vitro


2018 ◽  
Vol 40 (1) ◽  
pp. 82-89 ◽  
Author(s):  
Julieta Andréa Silva de Almeida ◽  
Mary Túlia Vargas Lobato Guedes de Azevedo ◽  
Marcus Vinicius Salomon ◽  
Priscila Fratin Medina

Abstract: The aim of this study was to evaluate the effect of water stress on the germination of Coffea arabica seeds and the growth and development of plants from these seeds. Seeds of the cultivars Bourbon Vermelho, Mundo Novo, and BA-10 were placed to germinate in the dark at 30 ºC in the presence and absence of 100 g/L of polyethylene glycol 6000. The water stress applied delayed the beginning of seed germination by seven days in relation to seeds of the control, which had achieved responses of up to 50%, but there were no differences between the treatments at the end of the experiment. Furthermore, the length of the primary root in seeds germinated under water stress was less than in the control treatment, especially for the cultivar Mundo Novo. Plants of the cultivars Bourbon Vermelho and Mundo Novo developed from seeds previously germinated under water stress exhibited reduced height and fewer leaf pairs than those from the control, whereas ‘BA-10’ responded in a similar way in both treatments. Thus, the cultivars Bourbon Vermelho and Mundo Novo were more sensitive to the water stress applied in the germination phase than ‘BA-10’.


2019 ◽  
Vol 40 (6Supl2) ◽  
pp. 2877
Author(s):  
Maria das Graças Rodrigues Nascimento ◽  
Maria Lúcia Maurício da Silva ◽  
Edna Ursulino Alves ◽  
Caroline Marques Rodrigues

Germination is negatively influenced by water scarcity and by temperatures above or below the optimal range of the species, so it is necessary to know the critical point of absorption for the species or cultivar. The objective of this work was to evaluate the effect of water stress, simulated by solutions of polyethylene glycol 6000 (PEG 6000) at different temperatures, on the germination and vigor of seeds of four cultivars (Branca, Orelha de Vó, Rosinha and Roxinha) of beans (Phaseolus lunatus L.). The water stress simulation was performed using PEG 6000 solutions at concentrations of 0.0, -0.2, -0.4, -0.6, -0.8, -1.0, and -1.2 MPa at temperatures of 25, 30, and 35 ° C. The analyzed variables were percentage of germination at first count, germination speed index, length of aerial part and primary root of seedlings, and dry mass of the respective parts of the seedlings. The seeds of the cultivar Orelha de Vó were more sensitive to water stress, with 88% germinating up to the potential of -0.6 MPa at the tested temperatures. The cultivars Branca, Rosinha, and Roxinha germinated (94, 100, and 100%, respectively) up to the potential of -0.8 MPa. Water stress simulated by PEG (6000) negatively affects seed twinning and seed vigor of bean cultivars.


2017 ◽  
Vol 79 (3) ◽  
Author(s):  
Abdu Muhammad Bello ◽  
Abdul Rahim Yacob ◽  
Kamaluddeen Suleiman Kabo

Mesoporous γ-Al2O3 with large surface area and narrow pore size was synthesized from acid-leachates of calcined kaolin in the presence of polyethylene glycol 6000 (PEG-6000) surfactant at room temperature. The synthesized alumina was characterized by X-ray diffraction (XRD), Nitrogen adsorption-desorption, Fourier transform infra-red spectroscopy (FTIR), field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray analysis (EDX), and thermogravimetric-Derivative thermal analysis (TG-DTA). High-purity mesoporous γ-Al2O3 with large surface area of 365.1 m2/g, narrow pore size distribution centred at 5.3 nm and pore volume of 0.46 cm3/g was obtained at 500 oC. When the calcination temperature has increased to 700 oC, the surface area decreased to 272.9 m2/g. Crystallite size calculated using Scherer’s equation revealed the average size of 4.33 and 4.12 nm for alumina calcined at 500 and 700 oC, respectively. The excellent pore structural properties (high surface area and large pore volume) of the synthesized mesoporous γ-alumina in the present study will allow for higher loading of active catalytic phases, as such it can be used as catalyst support.  


Sign in / Sign up

Export Citation Format

Share Document