Production of passion fruit virus-free in vitro shoots by apical meristem culture

Abstract

Passion fruit is a high economic value crop. Currently, the cultivated area of passion fruit in Lam Dong is decreasing due to the spread of viral diseases. The main aim of this study is to generate disease-free in vitro shoots for propagation purposes. The apical shoots of purple (Passiflora edulis Sims.) and yellow (Passiflora edulis f. flavicarpa) passion fruit cultivars collected at Dam Rong (T1 and V1) and Duc Trong (T2 and V2) districts, without surface sterilisation, were used as materials for apical meristem culture. The apical meristems (0.2 mm) of passion fruit plants were cultured on MS medium supplemented with 1.0 mg/l BA. After 4 weeks of culture, the survival and regeneration rate reached over 45.0%. Single shoots with green leaves were formed and regenerated after 10 weeks of culture. These regenerated shoots were tested for the presence of 3 viral groups (CMV, ToRSV and Potyvirus) by RT-PCR. The results showed that only 1 of 4 tested samples (V1) was infected with Potyvirus. Thus, these virus-free in vitro shoots will be used as materials for propagation to meet the requirement for disease-free purple and yellow passion fruit plants.