Assessment of different kenaf (Hibiscus cannabinus L.) accessions in hormone-free plant growth medium and identification of the associated fungal contaminants

Abstract

Kenaf is an industrial crop, which serves as income to small-holder farmers in Sub-Saharan Africa. Unfortunately, the oily and recalcitrant nature of its seeds makes seed germination during conventional propagation almost impossible. Plant tissue culture is a viable alternative to conventional propagation of kenaf seeds, however, it requires the use of expensive plant growth hormones and it is prone to fungal contaminations. This study therefore aimed at comparing the seedling growth of four different accessions of kenaf seeds (Tianung 2, Ifeken 100, Ifeken 400, and Ifeken D1 400) in half-strength growth hormone-free Murashige and Skoog (MS) medium as well as to identify the associated fungal contaminants in this medium. Data were obtained on plant length (cm), plant width (mm), number of leaves, leaf length (cm), number of roots, and root length (cm) at 14 days after culture (DAC). There were significant differences in all the growth parameters observed (p<0.05) except the plant width (mm) [p>0.05] at 14 DAC. Ifeken 400 had the highest average plant length (14.5 cm) followed by Ifeken 100 (10.5 cm) at p<0.05. On the other hand, the least average plant length (4.16 cm) was observed from both Tianung 2 and Ifeken D1 400 at p<0.05. The highest average root length (5.3 cm) was produced by Ifeken 400 while Ifeken DI 400 had the least average root length (2.6 cm) [p<0.05]. The fungal contaminants associated with the kenaf cultures in the half-strength growth hormone-free MS media were Aspergillus spp., Fusarium spp. and Penicillium spp. Therefore, half-strength growth hormone-free MS medium could be considered as a low cost alternative method of propagating kenaf seeds in order to prevent poor seed germination and allow for improvement of kenaf as an industrial crop. Keywords: Aspergillus spp ., Fungal contamination, Hibiscus cannabinus L., Plant growth hormones, Plant tissue culture DOI: 10.7176/JBAH/12-10-05 Publication date: May 31 st 2022