A successful strategy to eliminate banana streak virus in plantains is reported in a study published online in Communications Biology. This strategy, which uses CRISPR technology, could help improve plantain growth and yields.
Bananas, and their close relative plantains, are important staple food crops in tropical and subtropical countries. The development of varieties with improved resistance to disease and pests is vital to ensure healthy, high yields. Banana streak virus is a widespread pathogen that can eventually lead to the death of the plant. It works by integrating viral DNA into the B genome of the banana. When plants are stressed - for example, by drought or heat - the viral DNA produces functional viral particles, ultimately causing disease symptoms. As a result, breeders avoid using bananas that contain the B genome, like the wild banana Musa balbisiana, for crop improvement even though it has positive attributes, such as hardiness, a strong root system and tolerance to stress.
Jaindra Tripathi and colleagues used the CRISPR/Cas9 system to inactivate viral DNA from the B genome of the false horn plantain Gonja Manjaya. The Gonja Manjaya is a variety false horn plantain of the Musa genus commonly grown in East and Central Africa. The authors found that, when exposed to drought stress, 75% of the edited plants did not show any symptoms of banana streak virus compared to non-edited plants, which confirmed that viral DNA was deactivated.
The authors conclude that this strategy could be used to strengthen banana and plantain crops and to develop new hybrids with improved B genome.