Optimised germination protocol for jackfruit seeds and evaluation of methods for extraction of DNA suitable for genetic analysis

Abstract

Jackfruit (Artocarpus heterophyllus) is an underutilised plant that is promising in curbing food and nutritional security in sub-Saharan Africa. However, high level of secondary metabolites in its tissues significantly hampers its genetic characterisation for breeding purposes. Primarily, the compounds react with DNA during the extraction process, thus reducing its yield and quality. The utilisation of leaves from jackfruit seedlings is a potentially effective approach of addressing the challenge, however, limited information is available on efficient jackfruit seed germination procedures. Elucidating effective methods of jackfruit seed germination, and optimising protocols for DNA extraction is crucial in promoting its genetic characterisation studies for identification of superior varieties for propagation. The objective of this study was to evaluate methods of jackfruit seed germination, and DNA extraction procedures using jackfruit leaves. Pre-treatment of seeds with 3% hydrogen peroxide was effective in enhancing seed germination within a short time, compared to distilled water and 3% hydrochloric acid. We optimised a DNA extraction technique by combining CTAB-SDS based approach with an enhanced solvent extraction method. The technique yielded high quantity and quality of DNA from jackfruit leaves, which was appropriate for downstream polymerase chain reaction analysis. The sequence-related amplified polymorphism (SRAP) and simple sequence repeat (SSR) amplifications confirmed the effectiveness of the optimised CTAB-SDS based protocol for extraction of high quality DNA.