Molecular characterisation of Banana bunchy top virus (BBTV) from Pakistan

Abstract

Banana bunchy top disease is caused by a single-stranded circular DNA virus, banana bunchy top virus (BBTV), which is a member of the genus Babuvirus (family Nanoviridae). We have cloned and sequenced five components (DNA-R, DNA-S, DNA-N, DNA-M and DNA-C) of a BBTV isolate originating from Pakistan. In addition, the DNA-R and several other components of five further isolates, originating from geographically distinct sites across the banana-growing area of Sindh province, Pakistan, were cloned and sequenced. Analysis of the sequences indicates that BBTV present in Pakistan belongs to the "South Pacific" group of isolates and that the genetic diversity of the virus in the country is very low. The virus shows the highest levels of sequence identity to BBTV isolates originating from Egypt, India and Australia. The significance of these results with respect to the possible origin of the virus in Pakistan and the prospects for obtaining genetically engineered resistance to the virus are discussed.

Molecular characterization of banana bunchy top virus isolate from Sri Lanka and its genetic relationship with other isolates

“…BBTV isolates from India were found to be belonging to the PIO group [6,37,41]. Similarly, Amin et al [3] characterized the Pakistan (Sindh) isolate of BBTV by analyzing of sequences of DNA components and indicated that BBTV present in Pakistan belongs to the PIO group. The virus showed the highest levels of sequence identity to BBTV isolates originating from Egypt, India and Australia.…”

Molecular Characterization of Geographically Different Banana bunchy top virus Isolates in India

“…In India, BBTV has been prevalent since 1943 and so it is possible that genetic variability such as that observed among isolates of the Asian group exists. Recently, the complete genomes of BBTV isolates occurring in Pakistan [1] and Lucknow, North India [19] were reported and found to belong to the South Pacific group.…”

Advances in Small Isometric Multicomponent ssDNA Viruses Infecting Plants

“…1). BBTV is widely distributed in banana growing countries in the Asia, Pacific region (Australia, China, Guam, India, Pakistan, Sri Lanka, Hawaii, Indonesia, Japan, the Philippines, Taiwan, Tonga, Samoa and Vietnam) and in a few countries in Africa (Egypt, Gabon, Angola and Burundi) [2,16,50,89,99]. There are many other banana growing regions, South and Central America, the Caribbean, Papua New Guinea, Thailand and in many countries in African and Asia, where BBTV has not been confirmed [43,89].…”

“…The banana bunchy top disease was first observed of in Fiji in 1889. It emerged as a serious threat to banana cultivation in many countries, including Fiji in 1927, Egypt and India in 1953, the Philippines and Taiwan in 1961, Tonga and Samoa in 1967, China in 1979, Pakistan and Hawaii in 1989 [2,16]. In Australia, the banana industry in south-east Queensland and northern New Wales was virtually destroyed by the bunchy top disease in 1920 [16].…”

“…The mean sequence difference within each group was 1.9-3.0% and between the isolates from the two groups was about 10%. BBTV occurring in Indian [99] and Pakistan [2] has been characterized based on sequence of 5-6 components of DNA and both the isolates belonged to the South Pacific group. Phylogenetic analysis of major common region of all the six DNA components of BBTV showed a possible concerted evolution within the Pacific group due to recombination in this region [37].…”