scholarly journals Physiological and biochemical response of Phoenix dactylifera L. Hayani cv. embryogenic callus and somatic embryos to salt stress under in vitro conditions

Horticulturae ◽  
2021 ◽  
Vol 7 (10) ◽  
pp. 393
Author(s):  
Amal F. M. Zein El Din ◽  
Ola H. Abd Elbar ◽  
Saleh M. Al Turki ◽  
Khaled M. A. Ramadan ◽  
Hossam S. El-Beltagi ◽  
...  

The study of morpho-anatomical aspects, metabolic changes of proteins, antioxidant substances, as well as phenolic compounds in embryogenic callus (EC) and degenerative embryogenic callus (DEC) was the aim of the present investigation. Ability to form somatic embryos (SEs) was associated with the softness of the EC, which exhibited a white or creamy color and was composed of isodiametric cells containing dense cytoplasm, conspicuous nuclei and minimal vacuoles with observed mitotic activity. Furthermore, protein, reduced glutathione (GSH) and ascorbic acid (ASC) concentrations and the ratio between ASC and dehydroascorborbic acid (DHA) were increased significantly in the EC in comparison to the DEC. In addition, the phenolic extract of the EC was proved to have higher scavenging activity than the extract from the DEC. A loss of embryogenic competence in the DEC was correlated with the presence of more rigid clumps and such calli had a yellowish to brown color and no cell division could be observed in the cells of such aggregates as the cells had large vacuoles and they have very thick walls. Moreover, these morphological and anatomical observations of the DEC were accompanied by accumulations of the oxidized form of ascorbic acid (DHA), H2O2, total soluble phenolic compounds and overaccumulation of naringenin. Alternations in cellular metabolism can affect and regulate the morphogenesis of somatic embryos.


2020 ◽  
Vol 88 (2) ◽  
Author(s):  
Rizka Tamania SAPTARI ◽  
Masna Maya SINTA ◽  
Imron RIYADI ◽  
. PRIYONO ◽  
. SUMARYONO

The cultivation of date palm in Indonesia has increased since the last decade. However, the superior date palm seedlings are still limited and most of them are imported from other countries. The mass supply of superior date palm seedlings can be provided by in vitro propagation in the bioreactor. Therefore, the research was conducted to develop a protocol of date palm in vitro propagation by using Temporary Immersion Bioreactor (TIB). The in vitro propagation was carried out through somatic embryogenesis technique using meristematic tissues isolated from offshoots of date palm female clone cv. Zambli as explants. The explants were sterilized and then cultured to produce embryogenic calli and somatic embryos. Afterwards, somatic embryos germination and plantlets formation were conducted in TIB with treatments of immersion period: 3, 10, and 30 minutes every 6 hours, with 8 replications, The results showed that the optimal somatic embryo germination in TIB was with the immersion period of 30 min every 6 h, resulting in the most formation of shoots and fresh biomass weight increment up to nearly threefold in 6 weeks. Thereafter, plantlets formation in TIB with immersion period of 10 min and 30 min every 6 h exhibited similar performances in producing more plantlets with higher total fresh weight and better vigor than those of 3 min every 6 h. However, there were more rooted plantlets in the TIB with immersion period of 10 min every 6 h. Based on the results, an in vitro propagation protocol via somatic embryogenesis in TIB has been successfully developed for mass propagation of date palm cv. Zambli, which produced plantlets with good vigor and rooting.


2021 ◽  
Vol 9 (6) ◽  
pp. 1209
Author(s):  
Nuria Montes-Osuna ◽  
Carmen Gómez-Lama Cabanás ◽  
Antonio Valverde-Corredor ◽  
Garikoitz Legarda ◽  
Pilar Prieto ◽  
...  

Stress caused by drought and salinity may compromise growth and productivity of olive (Olea europaea L.) tree crops. Several studies have reported the use of beneficial rhizobacteria to alleviate symptoms produced by these stresses, which is attributed in some cases to the activity of 1-aminocyclopropane-1-carboxylic acid deaminase (ACD). A collection of beneficial olive rhizobacteria was in vitro screened for ACD activity. Pseudomonas sp. PICF6 displayed this phenotype and sequencing of its genome confirmed the presence of an acdS gene. In contrast, the well-known root endophyte and biocontrol agent Pseudomonas simiae PICF7 was defective in ACD activity, even though the presence of an ACD-coding gene was earlier predicted in its genome. In this study, an unidentified deaminase was confirmed instead. Greenhouse experiments with olive ‘Picual’ plants inoculated either with PICF6 or PICF7, or co-inoculated with both strains, and subjected to drought or salt stress were carried out. Several physiological and biochemical parameters increased in stressed plants (i.e., stomatal conductance and flavonoids content), regardless of whether or not they were previously bacterized. Results showed that neither PICF6 (ACD positive) nor PICF7 (ACD negative) lessened the negative effects caused by the abiotic stresses tested, at least under our experimental conditions.


2017 ◽  
Vol 17 (1) ◽  
pp. 9
Author(s):  
Yosi Zendra Joni ◽  
Riry Prihatini ◽  
Darda Efendi ◽  
Ika Roostika

<p>Somatic embryogenesis is a technique for regenerating embryos derived from somatic cells of various plant species. This technique along with the utilization of plant growth regulator (PGR) might benefit for mass propagation and improvement of plant species through biotechnological tools. The study aimed to determine the effect of different plant growth regu-lators, namely 6-benzyladenine (BA) and thidiazuron (TDZ) on the embryogenic callus induction as well as casein hydrolysate and malt extract on the somatic embryo development of mangosteen. The explants used were in vitro young stems of mangosteen clone Leuwiliang. This study consisted of two experiments, namely induction of embryogenic callus and formation of somatic embryo. The first experiment was arranged as factorial in a completely randomized design with BA (0 and 0.7 mg l-1) as the first factor and TDZ (0, 0.1, 0.5 and 1.0 mg l-1) as the second factor. The second experiment consisted of four treatments, i.e. casein hydrolysate and malt extract at the rate of 500 and 1,000 mg l-1. The results showed that the best medium for embryogenic callus induction was MS supplemented with 0.1 mg l-1 TDZ, which resulted semifriable calli. Casein hydrolysate and malt extract could not induce the formation of somatic embryos. After two times subcultures on the same MS medium supplemented with 0.5 mg l-1 TDZ and 0.7 mg l-1 BA, a total of 33.8 somatic embryos per explant was induced. The successful somatic embryogenesis would support mangosteen breeding and in vitro mass propagation program.</p>


2021 ◽  
Author(s):  
Emna Baklouti ◽  
Thierry Beulé ◽  
Amèni Nasri ◽  
Amal Ben Romdhane ◽  
Riadh Drira ◽  
...  

Abstract The present study is a part of a program designed at improving the date palm, Phoenix dactylifera L. cv. Barhee, through induced somaclonal variation. In this work, caulogenic cultures were subcultured on MS media supplemented with 0, 1, 5, 10, 20 and 40 mg L− 1 2,4-D in order to induce genetic and epigenetic variations. The highest doses of 2,4-D were found to induce severe negative effects on in vitro cultures, although some tissues were able to survive and to produce calli with high morphogenetic capacities. Our analysis showed some significant effect of 2,4-D on several physiological parameters. Indeed, chlorophyll and growth rates were found to drastically decrease while proline content increased from 535 nmol g− 1 to 2973 nmol g− 1 FW when 40 mg L− 1 2,4-D were used. In vitro cultures showed several signs of oxidative stress, such as high levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA); likewise, the specific activity of several antioxidant enzyme was found to increase. Plant regeneration from in vitro cultures treated with 2,4-D was obtained after subculturing explants onto PGR-free media. The ISSR analysis of 2,4-D-treated material showed that this plant growth regulator (PGR) induced measurable genetic variations. The global DNA methylation rates (GMR) as estimated through the HPLC analysis of nucleosides also confirmed the presence of epigenetic changes caused by 2,4-D as GMRs increased from 13.8–18.93%.


Sign in / Sign up

Export Citation Format

Share Document