scholarly journals Physiological responses of two halophytic grass species under drought stress environment

2016 ◽  
Vol 75 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Zamin Shaheed Siddiqui ◽  
Huda Shahid ◽  
Jung-Il Cho ◽  
Sung-Han Park ◽  
Tae-Hun Ryu ◽  
...  

AbstractThe physiological responses of two halophytic grass species, Halopyrum mucronatum (L.) Staph. and Cenchrus ciliaris (L.), under drought stress were evaluated. Biomass accumulation, relative water content, free proline, H2O2content, stomatal conductance, photosynthetic performance and quantum yield (Fv/Fmratio) were studied. Under drought conditions, these halophytic plants expressed differential responses to water deficit. Stomatal conductance and free proline content were higher in H. mucronatum than in C. ciliaris, while H2O2content in H. mucronatum was substantially lower than in C. ciliaris. Performance index showed considerable sensitivity to a water deficit condition, more so in C. ciliaris than in H. mucronatum. Results were discussed in relation to comparative physiological performance and antioxidant enzymes activity of both halophytic grasses under drought stress.

2019 ◽  
Vol 7 (2) ◽  
pp. 297
Author(s):  
Francisco Jose Basilio Alves ◽  
Antonio Lucineudo Oliveira Freire

This research aimed to evaluate the physiological responses of Mimosa tenuiflora plants submitted to variable water availability conditions during the nursery stage. Twelve-month-old plants kept in plastic pots containing 5 kg of the substrate composed of the subsoil soil mixture and bovine manure (2:1) were submitted to two treatments: irrigated (control) and water stress, which was imposed through the suspension of irrigation, rewatering after seven days of stress. The relative water content (RWC) and stomatal parameters were evaluated. The M. tenuiflora plants responded quickly to the irrigation suspension, promoting the closure of the stomata, occurring reduction in stomatal conductance, transpiration rate and photosynthesis. The instantaneous efficiency in water use of plants under water deficit remained high only until the middle of the period when irrigation was suspended, and then declined until the last day of the water deficit. After rehydration, the plants showed recovery in all evaluated parameters, indicating that the level of stress imposed did not cause irreversible damages in the cells and tissues.


2021 ◽  
Vol 13 (5) ◽  
pp. 2923
Author(s):  
Botir Khaitov ◽  
Munisa Urmonova ◽  
Aziz Karimov ◽  
Botirjon Sulaymonov ◽  
Kholik Allanov ◽  
...  

Water deficiency restricts plant productivity, while excessive soil moisture may also have an adverse impact. In light of this background, field trials were conducted in secondary saline soil (EC 6.5 dS m−1) at the experimental station of Tashkent State Agrarian University (TSAU), Uzbekistan to determine drought tolerance of licorice (Glycyrrhiza glabra) by exposure to four levels of water deficit, namely control (70–80%), moderate (50–60%), strong (30–40%) and intense (10–20%) relative water content (WC) in the soil. The moderate drought stress exhibited positive effects on the morphological and physiological parameters of licorice, and was considered to be the most suitable water regime for licorice cultivation. Plant growth under the 50–60% WC treatment was slightly higher as compared to 70–80% WC treatment, exhibiting weak water deficit promotes licorice growth, root yield and secondary metabolite production. In particular, secondary metabolites i.e., ash, glycyrrhizic acid, extractive compounds and flavonoids, tended to increase under moderate water deficit, however further drought intensification brought a sharp decline of these values. These results contribute to the development of licorice cultivation technologies in arid regions and the most important consideration is the restoration of ecological and economical functions of the dryland agricultural system.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Massimiliano Trenti ◽  
Silvia Lorenzi ◽  
Pier Luigi Bianchedi ◽  
Daniele Grossi ◽  
Osvaldo Failla ◽  
...  

Abstract Background Understanding the complexity of the vine plant’s response to water deficit represents a major challenge for sustainable winegrowing. Regulation of water use requires a coordinated action between scions and rootstocks on which cultivars are generally grafted to cope with phylloxera infestations. In this regard, a genome-wide association study (GWAS) approach was applied on an ‘ad hoc’ association mapping panel including different Vitis species, in order to dissect the genetic basis of transpiration-related traits and to identify genomic regions of grape rootstocks associated with drought tolerance mechanisms. The panel was genotyped with the GrapeReSeq Illumina 20 K SNP array and SSR markers, and infrared thermography was applied to estimate stomatal conductance values during progressive water deficit. Results In the association panel the level of genetic diversity was substantially lower for SNPs loci (0.32) than for SSR (0.87). GWAS detected 24 significant marker-trait associations along the various stages of drought-stress experiment and 13 candidate genes with a feasible role in drought response were identified. Gene expression analysis proved that three of these genes (VIT_13s0019g03040, VIT_17s0000g08960, VIT_18s0001g15390) were actually induced by drought stress. Genetic variation of VIT_17s0000g08960 coding for a raffinose synthase was further investigated by resequencing the gene of 85 individuals since a SNP located in the region (chr17_10,497,222_C_T) was significantly associated with stomatal conductance. Conclusions Our results represent a step forward towards the dissection of genetic basis that modulate the response to water deprivation in grape rootstocks. The knowledge derived from this study may be useful to exploit genotypic and phenotypic diversity in practical applications and to assist further investigations.


2020 ◽  
Vol 21 (8) ◽  
Author(s):  
M Miftahudin ◽  
Rury Eryna Putri ◽  
Tatik Chikmawati

Abstract. Miftahudin, Putri RE, Chikmawati T. 2020. Vegetative morphophysiological responses of four rice cultivars to drought stress. Biodiversitas 21: 3727-3734. Each rice genotype develops certain morphophysiological responses to drought stress. The study aimed to analyze the morphophysiological responses of vegetative aspect of four rice cultivars to drought stress. A 10% Polyethylene glycol-6000 was added to a Yoshida nutrient solution medium as a drought stress stimulant for four rice cultivars, i.e., IR64, Hawara Bunar, Situbagendit, and Inpago 10. Fourteen-days-old rice seedlings were grown on the media with and without drought stress treatment for 9 days, and morphophysiological characters of vegetative aspects were observed. Drought stress inhibited the shoot growth of cv. Hawara Bunar, but increased shoot growth of cv. Inpago 10. The physiological responses in the form of leaf relative water content, proline, malondialdehyde (MDA), and total chlorophyll contents in cv. Hawara Bunar was inversely proportional to those of cv. IR64 showed an inferior response to drought stress. The rice cv. Hawara Bunar might develop better response mechanisms to drought than that of cv. IR64. The physiological responses of cvs. Situbagendit and Inpago 10 were in between the other two cultivars. We conclude that the variation of morphophysiological responses to drought stress among rice cultivars is an indicator of tolerance capability to drought that could be used as early-growth selection criteria in rice breeding programs for drought tolerance.


Author(s):  
L. He ◽  
J.-H B. Hatier ◽  
S.D. Card ◽  
C. Matthew

Drought stress is one of the limiting factors in perennial ryegrass growth and development. In order to investigate the drought responses among different cultivars and evaluate the role of fungal endophyte in modifying drought responses, a glasshouse experiment was conducted using ryegrass cultivars 'Alto' and 'Banquet II', and a Mediterranean tall fescue cultivar, 'Grasslands Flecha' as contrast with the two ryegrass cultivars. Under drought stress 'Flecha' had a higher stomatal conductance and transpiration rate than the two ryegrass cultivars, and also significantly greater deeproot allocation. Endophyte-infected plants exhibited reduced leaf dehydration under stress compared with endophyte-free plants. Under stress, endophyte-free plants displayed significantly lower relative water content and a more negative leaf water potential and osmotic potential than well-watered endophyte-free plants, whereas endophyte-infected plants displayed smaller and non-significant changes when subjected to water deficit stress. Endophyte-infected plants also had less deep-root allocation than endophyte-free plants. The results of this study increase understanding of the relationship between endophytes and their ryegrass or tall fescue hosts under drought stress. Keywords: deep-root allocation, Epichloë, gas exchange parameters, Neotyphodium, plant water relations, Lolium perenne


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Vincent Ezin ◽  
Artoche Gloria Christelle Tosse ◽  
Ifagbémi Bienvenue Chabi ◽  
Adam Ahanchede

Cowpea (Vigna unguiculata (L.) Walp.) is an important commodity in West Africa. Its seeds are a valuable source of protein, vitamins, and income for humans. However, cowpea cultivation in Benin faces climatic constraints such as water stress caused by a prolonged absence of rain during the rainy season. Thus, this work aims at selecting cowpea varieties that can be cultivated in times of drought without compromising their yields and yield components. Twenty cowpea varieties were used, including 17 improved cultivars and 3 landraces. The experiment was conducted at the International Institute of Tropical Agriculture in Benin and laid at a split-plot design with four replicates. Each genotype was exposed to three water treatments: fully irrigated control, vegetative stress (when plants were 23 days old, drought stress was imposed for 30 days), and reproductive stress (once the first flowers were observed, water stress was imposed for 30 days). The results showed that photochemical yield, chlorophyll content, and relative water content were reduced under water deficit at the vegetative and reproductive stages. But there were no significant differences in proline content among cowpea varieties. Agronomic traits such as number of days to flowering, number of pods, yield per plant, the weight of 100 seeds, and harvest time showed significant differences under water stress. Overall, the landraces and cultivars including Kpodjiguegue, KVX 61-1, and IT 06-K-242-3 were the most tolerant to drought stress at the vegetative and reproductive stages and could potentially be used in breeding programs to improve drought tolerance of cowpeas.


1993 ◽  
Vol 73 (2) ◽  
pp. 525-529 ◽  
Author(s):  
Allen G. Good ◽  
James L. Maclagan

The physiological responses of different species of Brassica to induced drought stress were studied by analysing the relationships between relative water content, leaf water potential and leaf osmotic potential during the onset of drought stress. These data indicate that while there was a decrease in leaf osmotic potential with the onset of drought stress, this did not result from a net increase in solutes. Therefore, these genotypes of Brassica do not appear able to osmoregulate under these drought conditions. Key words: Brassica, drought, osmoregulation, water stress


2007 ◽  
Vol 62 (5-6) ◽  
pp. 410-416 ◽  
Author(s):  
Ying Yang ◽  
Feng He ◽  
Longjiang Yu ◽  
Xuehong Chen ◽  
Jing Lei ◽  
...  

The effect of water deficit on flavonoid production and physiological parameters characteristic for oxidative stress were studied in a cell suspension culture of Glycyrrhiza inflata Batal to investigate its drought tolerance. The result indicated that appropriate water deficit enhanced biomass accumulation of 27.1 g L-1 and flavonoid production of 151.5 mg L-1, which was about 2-fold and 1.5-fold of the control, respectively. But it decreased the water content. Drought stress led to hydrogen peroxide accumulation more than in the control. Moreover, under drought conditions, malondialdehyde content, the activities of catalase and peroxidase increased to a greater extent than the control, and each reached a maximum value of 91.3 μmol g-1 dry weight, 85.6 U and 1951 U g-1 dry weight per min, which was 1.5-, 1.7- and 3.7-fold of the control, respectively. All above showed that appropriate water deficit could activate the antioxidative defense enzymes system to maintain stability in plants subjected to drought stress. On the contrary, the activity of phenylalanine ammonia lyase of the control increased in company with the biosynthesis of flavonoids, which indicated that phenylalanine ammonia lyase might play an important role in the path of the biosynthesis of flavonoids.


2010 ◽  
Vol 22 (3) ◽  
pp. 189-197 ◽  
Author(s):  
José Perez da Graça ◽  
Fabiana Aparecida Rodrigues ◽  
José Renato Bouças Farias ◽  
Maria Cristina Neves de Oliveira ◽  
Clara Beatriz Hoffmann-Campo ◽  
...  

To investigate the processes involved in the susceptibility of sugarcane plants to water deficit, several physiological parameters were evaluated in drought tolerant (SP83-2847 and CTC15) and sensitive (SP86-155) cultivars. The water deficit affected the photosynthetic apparatus of all the plants in different ways, within and among cultivars. The photosynthetic rate and stomatal conductance decreased significantly in all cultivars submitted to water deficit. In control plants of the tolerant cultivars (SP83-2847 and CTC15) the photosynthetic rate was higher than in the sensitive cultivar (SP86-155). Cultivar CTC15 showed the highest relative water content during the dry period. The quantum efficiency photosystem II of cultivar SP83-2847 was more stable in the last days of the experimental treatment, suggesting that the decline in relative water content stimulated an adjustment of photosynthetic capacity to tolerate the changes in water availability. As a whole, the tolerant SP83-2847 and CTC15 cultivars exhibited a better photosynthetic performance than the sensitive SP86-155 cultivar. The data suggest that these physiological parameters can be used in the evaluation and distinction of drought tolerant and sensitive sugarcane genotypes.


1980 ◽  
Vol 10 (1) ◽  
pp. 10-16 ◽  
Author(s):  
R. A. Kandiko ◽  
R. Timmis ◽  
J. Worrall

Pressure–volume curves for western hemlock (Tsugaheterophylla (Raf.) Sarg.) seedlings showed roots to have lower osmotic potentials, at both full turgor and incipient plasmolysis, and lower relative water contents at incipient plasmolysis than shoots. Roots remained turgid under mild water deficit, whereas shoots lost turgor exponentially with water content. Shoots of seedlings given a 2-week drought stress had lower osmotic potentials at full turgor and incipient plasmolysis than shoots of unstressed seedlings; roots showed a similar trend.


Sign in / Sign up

Export Citation Format

Share Document