Techniques for Improving the Tissue Culture Efficiency of Purple Passion Fruit (Passiflora edulis)

Abstract

Purple passion fruit (Passiflora edulis Sims) has gained attention in Southern China, and its planting area has increased during the last several years. Through tissue culturing, virus-free plants are produced as maternal parents for seedling production. However, there are some difficulties that affect passion fruit tissue culture efficiency, including high contamination rates in explant disinfection, low shoot proliferation, yellow or albino leaves, slow growth, and time-consuming processes. In this work, the aforementioned problems were investigated, and disinfection was optimized. Results revealed that the repeat disinfection method (0.1% HgCl2 for 15 min + 0.1% HgCl2 for 12 min) with a 2-d interval was the most suitable disinfection treatment for young stem segments of purple passion fruit. The addition of silver thiosulfate (STS) improved proliferation efficiency. Moreover, additional 1X iron salt was added to the bud induction and rooting medium. The regenerated shoots had a better seedling state with healthier green leaves, roots were more easily induced and better developed and the chlorophyll contents were higher. Thus, more efficient tissue culturing of purple passion fruit was achieved. © 2021 Friends Science Publishers