PRESENCE OF BACILLUS PUMILUS CAUSING FRUIT ROT OF FICUS LACOR IN PAKISTAN
H.S. Naz, F. Liaquat, S. Gul, H.J. Chaudhary, M.F.H. Munis
Ficus lacor (pakhar), a member of the family Moraceae, is known for its medicinal use. Whereas decoction of buds is used for ulcer and leucorrhoea, seeds are used to cure gastric problems, ulcer, typhoid fever, dysentery and boils (Rai et al., 2004). In 2014-15, some 40-50 fruits of F. lacor were collected from different areas of Islamabad and Rawalpindi, which showed dark and light brown spots, that progressed further rotting the whole fruit. For the isolation of the putative causal agent of the disease, the infected parts of the fruits were surface- sterilized with 2% sodium hypochlorite and placed directly on potato dextrose agar (PDA) and Luria-Bertani (LB) media. Bacterial growth were observed on LB plates only. The pathogenicity of bacterial isolates was assessed by injecting a cell suspension (calibrated at 108 CFU/ml) in healthy F. lacor fruits. Symptoms similar to those shown by naturally infected fruits developed o 4 to 6 days post inoculation. Control fruits injected with sterilized distilled water remained healthy. A 16S RNA gene fragment of 1013 bp was amplified from bacterial isolates and sequenced, showing 99% similarity with the Bacillus pumilus strain TE07 16S ribosomal RNA gene. The sequence was deposited in GenBank under the accession No. KJ833786.1. B. pumilus is a spore-forming rod-shaped Gram-positive and aerobic bacterium which can infect several hosts including leaves of cabbage and peach, and fruits of apricot, apple, cucumber, olive and squash, and flower head of cauliflower and cloves (Galal et al., 2006). To our knowledge, this is the first report of B. pumilus causing fruit rot of F. lacor in Pakistan.