Resistance of Musa balbisiana accessions of the Philippines to banana bunchy top virus

Abstract

Mitigation of banana bunchy top disease is still a challenge worldwide. BBTD is caused by banana bunchy top virus the most important virus affecting banana. Currently, no cultivar or accession has complete resistance to BBTD. A total of 36 wild Musa spp accessions including 34 Musa balbisiana and two Musa acuminata subsp. errans were screened for resistance against BBTV. In greenhouse tests using viruliferious banana aphids, all Musa balbisiana accessions remained symptomless and BBTV was not detected in any of these plants by PCR at three- and six-months post-inoculation. In contrast, 100 percent disease incidence was recorded in Musa acuminata subsp. errans and in cv. Lakatan susceptible control plants. The PCR-negative Musa balbisiana were then transferred to a field with high BBTV inoculum pressure where they remained symptomless and PCR-negative for up to five years while all cv. Lakatan developed BBTD. This study confirmed the resistance of wild Musa balbisiana accessions to BBTV. It is therefore expected to provide a resource to conventional and marker assisted breeding.

Comparative RNA-seq analysis of resistant and susceptible banana genotypes reveals molecular mechanisms in response toBanana bunchy top virus(BBTV)

“…By comparing to the susceptible banana genotype, we were able to identify resistance genes that may contribute to the high degree of BBTV resistance reported in wild M. balbisiana 8 . Our work demonstrates that natural BBTV resistance found in the wild encompasses complex and multi-component mechanisms 104 .…”

“…Hence, identification of new sources of resistance alleles to be introgressed in the existing elite varieties is still an area of further research. Fortunately, the Philippines has local access to natural genetic resources such as wild Musa balbisiana accessions with complete resistance against the pathogen 8 .…”