In vitro Tuberization using Silicon Nanoparticles and short-term cold Storage of mini-tubers of Dioscorea pentaphylla L.

Experimental studies have been conducted to evaluate the induction of mini-tubers in vitro from shoots of Dioscorea pentaphylla L. as affected by applications of Silicon nanoparticles (SiNPs). Amorphous nano-silica is a low-cost material and is considered biologically safe because of its biodegradability. A maximum number of mini-tubers (1.9) per shoot differentiated in Murashige and Skoog (MS) nutrient medium pre-optimized with growth regulators (0.5 mg L − 1 m T/ meta -Topolin and 0.1 mg L − 1 IAA/indole-3-acetic acid) supplemented with 8.0 mg L − 1 of SiNPs. Microscopic examination of tubers revealed the presence of outer cork, phellogen, adjacent chlorenchymatous tissues, parenchymatous ground tissue, and unevenly distributed collateral vascular bundles. The ground tissue exhibited dense starch grains and sclereids. The in vitro-developed mini-tubers could be subjected to short-term cold storage in the dark at -4 o C for 12 months on hormone-free MS medium. Shoot regeneration through organogenesis from 93.0% of the cold-stored tubers occurred on MS medium with 1.0 mg L − 1 m T. The shoots proliferated on 0.5 mg L − 1 m T and 0.1 mg L − 1 IAA and formed complete plantlets. All of the tuber-derived plantlets survived under ex vitro and in vivo environmental conditions. The process developed has the potential to serve as a novel technique for enhanced production of mini-tubers using SiNPs and in vitro conservation of germplasm of Dioscorea spp.