Mature seed-derived nodal explants: A season-independent explant source for in vitro culture in maize

Abstract

Maize is an important industrial crop having multifarious uses including ethanol production and animal feed, and human food. To achieve fuel and food security there is a need to develop high-yielding and climate-resilient cultivars. Tissue culture and genetic transformation are viable approaches for developing crop plants with improved and novel traits. For maize tissue culture endeavours, immature embryos are the most widely used explant globally due to their very high regeneration potential. However, immature embryos as an explant source have a few major drawbacks including their availability in particular seasons, difficulty in storage, and excision of them is quite a laborious and time-consuming process. All these limitations can be easily addressed by utilizing mature seed-derived nodal explant as starting material for tissue culture experiments. These are season-independent (i.e., available throughout the year), and easy to handle and use. The present manuscript highlights the importance of mature seedderived nodal explants for in vitro regeneration and transformation in maize. The various steps followed for obtaining embryogenic callus from nodal explants are also summarized here.