Micropropagation, encapsulation, physiological, and genetic homogeneity assessment in Casuarina equisetifolia

Abstract

Casuarina equisetifolia is an important tree of the forest, cultivated in tropical and subtropical regions, providing fuelwood, land reclamation, dune stabilization, paper production, and nitrogen fixation. We have developed a systematic in vitro propagation protocol in C. equisetifolia using nodal segments (NS). Murashige and Skoog (MS) medium augmented with BA (5.0 μM) and NAA (0.5 μM) gave rise to a maximum of 32.00 ± 0.31 shoots per explant (S/E) with shoot length (SL) of 3.94 ± 0.02 cm, and a maximum of 70% regeneration potential (RP) was recorded after 8 weeks of post inoculation. For root induction, in vitro derived shoots were transferred to the nutrient medium consisting of a half-strength (½) MS medium augmented with 2.5 μM NAA, which produced a maximum of 12.68 ± 0.33 roots/shoot (R/S) with 3.04 ± 0.50 cm root length (RL) in 60% of culture after 6 weeks. Micropropagated plants with healthy shoots and roots were successfully acclimatized in vermicompost + garden soil + sand (1:2:1) and a maximum survival percentage of 95.1% was recorded. NS was taken from a 6-weeks-old in vitro derived plant of C. equisetifolia for synthetic seed production, and it was reported that CaCl2 · 2H2O (100 mM) + Na2-alginate (4%) resulted in clear and uniform beads. Furthermore, the maximum conversion of synthetic seeds into plantlets occurred over a period of 4 weeks of storage at 4°C. Scanning Electron Microscopy (SEM) revealed the formation of direct shoot buds without any intermediate callus formation. In addition, the chlorophyll and carotenoid contents of the direct regenerated and mother plant were compared. Similarly, RAPD and ISSR primers were used for genetic homogeneity assessment of the direct regenerated plants, where a total of 18 and 19, respectively, clear and reproducible bands with 100% monomorphism were recorded. The developed micropropagation protocol can certainly be used for large-scale multiplication and germplasm preservation of C. equisetifolia. It will also help in meeting the growing demands of C. equisetifolia in the forest industry.

In Vitro Microrhizome Production, Genetic Homogeneity Assessment, and Field Performance Evaluation in Ginger

“…Genetic uniformity of in vitro-produced progenies is critical for commercial applications [34,35]. However, numerous factors, including the explant sources, medium components, and duration and number of subcultures, can induce morphological, cytological, genetic, and epigenetic variations in regenerated plants [47].…”

“…Typically, these factors are PGRs or carbohydrate levels [23,25,26]. High genetic homogeneity is critical for successful clonal propagation of plants regenerated in vitro [34,35]. Despite extensive research into microrhizome induction in ginger over the last decades, there still needs to be more understanding of the genetic homogeneity of in vitro-induced microrhizomes.…”

Rapid and Efficient Regeneration of Rhododendron decorum from Flower Buds

“…A reasonable ratio of growth regulators is especially crucial for the induction and proliferation of adventitious shoots; thus, the formulas of the growth regulators in tissue culture systems vary among [41,42]. In the tissue culture process of woody plants, the commonly used plant growth regulators are TDZ, NAA, IBA, and kinetin [43,44]. However, different species have different degrees of sensitivity to plant growth regulators.…”