Storage of Plant Species with Desiccation-Sensitive Germplasm in a Compact Growth Chamber for Long-Term Space Missions

Plant species sensitive to desiccation or vegetatively propagation are difficult to store and transport in the germplasm for space travel. Applying plant tissue culture can help to create a Plant Germplasm Bank for this species. For this purpose, the Compact Growth Chamber (CGC) was created to store and transport in vitro explants, maintaining them for long periods in Slow-Grown Storage (SGS). Explants under SGS have reduced growth metabolism to complete space missions. This study aimed to evaluate the CGC efficacy in the long term of in vitro storage of explant of Taioba (Xanthosoma sagittifolium), a tropical species that vegetatively propagates and has high nutritional value. For this, three CGCs were connected, side by side, with different LED light spectra (CGC1: Red spectrum; CGC2: 50% Red + 50% Blue spectra-control; CGC3: Blue spectrum), each one containing nine test tubes with taioba explants (one per test tube), and LED lights intensity adjusted for 30 µmol m−2 s−1. The CGCs were maintained for 120 days in the darkroom, at 25 ± 2 °C temperature and 50–60% humidity, and, at the end, the growth and morphological parameters of taioba plantlets were evaluated. These results demonstrate that the explant storage in CGC3 showed lower root numbers and root lengths than in CGC1 and CGC2. In addition, the Blue spectrum in CGC3 reduced the root oxidation and browning, resulting in 100% live explants. This study provides that the CGC fulfilled its proposed function of transporting and storing the in vitro explants for space travel.