scholarly journals Physiological and biochemical changes of micropropagated Dendrobium anosmum Lindl. in ex vitro acclimatization process

Author(s):  
Bang Phi Cao

The ex vitro acclimatization process plays an important role in plant micropropagation. In vitro plantlets have to rapidly adapt to environmental changes. The current work aimed at assessing some physiological and biochemical changes of micropropagated Dendrobium anosmum Lindl. Plantlets during ex vitro acclimatization process, eg. contents of water (leaf relative water content), dry matter, proline and photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoid), chlorophyll fluorescence and antioxidant enzymes (peroxidase và catalase) activities. The analyzed results showed that water content decreased in acclimatized plantlets compared to in vitro ones. The chlorophylls and carotenoids contents of what were significantly higher in ex vitro plantlet leaves compared to the day 0 plantlets. The pigment contents were observed to increase during the ex vitro acclimatation process. When the plantlets were moved out of the in vitro medium, the maximum photochemical efficiency of photosystem II (Fv/Fm) significantly decreased at the early acclimatation points then restored at the end of acclimatation process. The content of proline and activities of antoxidant enzymes significantly increased with different periods of acclimatation process. The proline content and enzyme activities were recorded at the first ex vitro period when most water loss occurred in plantlets. These results suggest that Dendrobium anosmum Lindl in vitro plantlets have adapted to the transplantation by possesing some physiological responses of its photosynthetic system as well as its antioxidant machinery.

Author(s):  
Cao Phi Bang

The ex vitro acclimatization and greenhouse periods play a significant role for the in vitro originated plantlets. In these stages, the micropropagated plantlets have to rapidly adapt to environmental changes. Rhynchostylis gigantea is widely in vitro produced due to highly aesthetic and economic value. The aim of this work was to update the physiological changes of micropropagated R. gigantea plantlets during ex vitro acclimatization and greenhouse stages. The analysis results showed that leaf water content was significantly decreased at day 14 (90.36%) and day 28 (90.17%) stages but increased at day 84 (92.52%) and day 140 (92.34%) stages in compared to in vitro stages, day 0 (92.7%). Dry matter content was changing in the opposite direction to the leaf water content with the highest values at day 14 (9.63%) and day 28 (9.83%), respectively. The leaf transpiration rate was the highest at day zero (0.146 g/dm2/h) in compared to all other studied points. Oppositively, GPX activity was the lowest in plantlets at day zero (13.2 UI/g fresh leaf ) and the highest in planlets at day 14 (36,4 UI/g fresh leaf ). The leaf proline content was higher at day 7 and day 14 stages (132.3 and 150.8 m g/g fresh leaf, respectively) but lower at day 84 and day 140 stages (44.3 and 53.3 microgram/g fresh leaf, respectively) than at day zero (73.7 microgram/g fresh leaf ).


Author(s):  
Erum F H Kazi ◽  
Dr. Satish Kulkarni

Air pollution is one of major concerns in Pune City currently. Study highlights increase in Particulate matter from Vehicular sources & Urbanization in Karaj area is having harmful impact on the trees in the area. Leaf of Plant species such as Peepal( Ficusreligiosa),, Tamarind(Tamarindusindica), Rain tree( Samaneasaman), Ashoka( Saracaasoca), Manago( Mangiferaindica), Almond( Terminaliacatappa) , Banyan tree(Ficusbenghalensis) were selected and it was found that Ashoka( Saracaasoca), Mango tree( Mangiferaindica) showed Intermediate APTI whereas Peepal, Tamarind, Rain tree, Almond, Banyan tree were found to be Sensitive to pollution. KEYWORDS: Air Pollutants, APTI of plants, Total Chlorophyll, Ascorbic acid, p H of leaf, Relative water Content ( RWC)


2016 ◽  
Vol 27 (2) ◽  
pp. 128-135 ◽  
Author(s):  
J Akte ◽  
S Yasmin ◽  
MJH Bhuiyan ◽  
F Khatun ◽  
J Roy ◽  
...  

Five rice varieties viz. Binadhan-4, Binadhan-5, Binadhan-6, Binadhan-10 and Iratom-24 were evaluated in vitro under different water stress conditions. Several parameters such as germination percentage, shoot length, root length, shoot-root ratio, fresh weight, dry weight, turgid weight, relative water content and proline accumulation were studied. Drought condition was created by MS medium supplemented with five treatments of PEG, with a control such as 0%, 1%, 2%, 3% and 4% of PEG. The highest germination (100%) was found in the variety Binadhan-10 under low water stress conditions induced by 1% PEG. Similarly, the highest percentage of germination was found in all varieties under control condition (0% PEG). The lowest percentage of germination was obtained in the variety Iratom-24. But under severe stress (4% PEG), the highest percentage of germination was found only in the variety Binadhan-10. Moreover, the variety Binadhan-10 was found to be the best at 4% PEG for shoot length, root length, shoot-root ratio, relative water content and also the best at 1% PEG for fresh weight, dry weight, turgid weight. Water stress decreased relative water content and increased proline accumulation in rice. The highest relative water content was recorded in the variety Binadhan-10 and the lowest value recorded in the variety Binadhan-5. The highest proline content was obtained from the binadhan-6 at the highest treatment (4% PEG). Binadhan-10 showed the best performance almost in all the parameters under drought stress because of its own nature of tolerancy.Progressive Agriculture 27 (2): 128-135, 2016


1997 ◽  
Vol 24 (1) ◽  
pp. 49 ◽  
Author(s):  
K. M. Volkmar

This experiment as undertaken to determine the efects of soil drying around the nodal and/or seminal root systems on the shoot growth of wheat (Triticum aestivum L.). Two split-root experiments were conducted, the first on newly emerged nodal roots of 18-day-old wheat plants, the second on 25-day-old plants. In both experiments, nodal and seminal roots were isolated from one another and water was withheld from either the nodal root chamber, the seminal root chamber, or both, over 6 days. In the first experiment, leaf growth was unaffected by withholding water from very short nodal roots, even though leaf relative water content of the droughted plants decreased. By comparison, both leaf elongation rate and relative water content decreased by withholding water from the seminal roots. On plants that were 1 week older, leaf growth rate and leaf relative water content decreased when nodal roots were drought-stressed. Leaf growth rate of seminal root droughted plants was more impaired than their nodal root counterparts, even though leaf relative water contents of the two treatments were the same. In both experiments, drought stress applied to the nodal root system enhanced nodal root growth more than seminal roots. These results suggest that seminal and nodal roots perceive and respond to drought stress differently with respect to the nature of the message conveyed to the shoots.


1953 ◽  
Vol 36 (6) ◽  
pp. 739-749 ◽  
Author(s):  
Ingrith Deyrup

Rat renal cortical and medullary tissues show a marked elevation of relative water content when immersed in "physiological solutions" containing sodium and chloride ions, or in equally concentrated solutions of monosaccharides. In contrast to this, no increase in relative water content occurs in isosmotic solutions of three disaccharides studied. It appears to be unlikely that the fluid uptake is a result of intracellular hypertonicity existing either physiologically or pathologically. A more satisfactory alternative hypothesis is that ingress of water accompanies entrance of solutes (ions, monosaccharide molecules) into the tissue cells.


2016 ◽  
Vol 36 (1) ◽  
pp. 83-95
Author(s):  
Mack Moyo ◽  
Stephen O. Amoo ◽  
Adeyemi O. Aremu ◽  
Lucie Plíhalová ◽  
Jiří Gruz ◽  
...  

2021 ◽  
Vol 49 (1) ◽  
pp. 12049
Author(s):  
Tekam L. MEGUEKAM ◽  
Dany P. MOUALEU ◽  
Victor D. TAFFOUO ◽  
Hartmut STÜTZEL

Salinity is the main environmental factor accountable for decreasing crop productivity worldwide. The effects of NaCl salinity on plant growth (leaf relative water content (RWC), leaf dry weight (LDW), shoot length (SL), number of leaves (NL), number of branches (NB) and total leaf area (TLA) and physiological characteristics (stomatal conductance (gs), transpiration rate (TR), net photosynthetic (Pn), yield of photosystem II (ΦPsII) and the intercellular CO2 concentration (CO2int) in peanut (Arachis hypogaea L.) varieties (‘Vanda’, ‘P244601’ and ‘Pl184948’, widely used in Cameroon, Tanzania and Ghana, respectively, were investigated under hydroponic condition. Plants were subjected to four levels of NaCl (0, 40, 80 and 120 mM) at early seedling growth stage of plant development. Application of NaCl treatment led to a significant decrease in LDW, SL, NL, TLA, Pn, gs, TR and CO2int concentration of ‘Vanda’ and ‘P244601’ compared to untreated plants while the plant growth inhibition was notably noted at 120 mM NaCl in ‘P1184948’ for LDW, SL and NB. The highest depressive effect was detected in gs of salt-sensitive ‘Vanda’ while the lowest were recorded in gs of salt-tolerant ‘P1184948’ at high salinity level. Enhanced NaCl concentrations led to a significant increase in ΦPSII of ‘P1184948’ compared to ‘Vanda’, ‘P244601’ and untreated plants. Leaf CHL content was significantly increased in moderately-tolerant ‘‘P244601’ and salt-tolerant ‘P1184948’ at 80 mM NaCl compared to salt sensitive ‘Vanda’ and untreated plants. The depressive effect of salt on RWC was recorded at 120 mM NaCl in peanut leaves of all varieties. Under salt stress ‘P1184948’ was observed to have relatively higher tolerance on average of all growth and physiological traits than ‘Vanda’ and P244601’ suggesting that it could be grown in salt-affected soils.


HortScience ◽  
2013 ◽  
Vol 48 (2) ◽  
pp. 216-221
Author(s):  
Ariningsun P. Cinantya ◽  
Fure-Chyi Chen ◽  
Yao-Chien Alex Chang

The popularity of the nobile-type dendrobium (Dendrobium nobile hybrids) has been increasing globally. More information regarding the effects of long-distance shipping, from producing countries to destination market countries, on the post-shipping plant performance is needed. In this study, two nobile-type dendrobium cultivars were subjected to simulated dark shipping (SDS) at various temperatures and durations. Changes in net CO2 uptake rate (Pn), chlorophyll fluorescence, and leaf relative water content after plants had been treated with SDS were investigated. Furthermore, shipped plants were vernalized to investigate the effect of dark shipping on the subsequent flowering quality. Dark shipping for 7 days at 15 °C did not affect the post-shipping photosynthetic performance of D. Lan Tarn Beauty. Increasing the shipping duration from 7 to 21 days increased the time required for Pn recovery from 1 to 12 days. Dendrobium Lan Tarn Beauty recovered its Pn within 4 days when shipped for 21 days at 10 °C, and this was prolonged to 11 days when the plants were shipped at 20 °C. Changes in Fv/Fm indicated that there was no marked damage to either cultivars, and the leaf relative water content was little affected by SDS. Dendrobium Lan Tarn Beauty and D. Lucky Girl shipped at 10 °C flowered 5 and 8 days earlier, respectively, compared with unshipped plants. Regardless of the shipping conditions, shipped D. Lucky Girl had a lower flower diameter and higher total flower count than unshipped plants. No differences were found in the number of nodes with flowers or the total flower count between shipped and unshipped D. Lan Tarn Beauty. Our study suggested that dark shipping for up to 21 days is possible for nobile-type dendrobiums. We recommend shipping temperatures of 10 to 15 °C to reduce the detrimental effects caused by long-term dark shipping.


Sign in / Sign up

Export Citation Format

Share Document