Disease-resistant banana varieties in development stage

MANILA, Philippines – Banana growers are in a fight for survival, continuously adopting new methods to deter pests and diseases.

While banana production in the country is high, it remains to be greatly affected by various diseases, giving the fruit an uncertain future.

The banana is an important fruit crop in the Philippines due to its potential both in the local and international markets.  However, it is vulnerable to a lot of diseases such as  Fusarium wilt with tropical race 4  (which threatens the Cavendish varieties), banana bunchy top virus,  Sigatoka, bacterial wilt, and insect pests.

The Philippines is the third  largest producer of banana in the world next to India and China and is the fourth  largest agricultural produce of the Philippines in 2011 recorded at 9.16 million metric tons valued at $ 2.32 billion.

The Cavendish banana is the export variety constituting half of the country’s production.   It provides employment to almost 330,000 Filipinos.

On the other hand, lakatan is the most common dessert banana in the country, while saba is the cooking-type banana.

Because of the major effect of pests and diseases on banana productivity, the Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development of the Department of Science and Technology (DOST-PCAARRD) crafted the Banana Industry Strategic S&T Program (ISP) which aims to reduce the incidence of Foc TR4 on Cavendish in Mindanao by 90-95 percent.

The program also aims to increase the average yield of lakatan from 21.58 mt per hectare to 34.52 mt/ha, reduce the incidence of BBTV from 70 percent  to 20 percent, and boost production of saba for banana chips production by 33 percent per cropping season.

The DOST-PCAARD intends to achieve its goals through the use of resistant varieties that are suitable under Philippine condition and acceptable to the export market. The use of these varieties can be complemented with the application of commercially available microbial agents that have the potential to lessen the impact of Foc TR4.

The Giant Cavendish Tissue Culture Variants (GCTCV) 218 and 219 are the Cavendish somaclones from Taiwan that show promise as alternative to Grand Nain (GN).

GCTCV 219 has relatively lower yield at an average of 18 kilograms/bunch but is relatively sweeter and can be marketed as highland banana.

Greenhouse and field trials on the use of commercially available microbial agents showed that application of Trichoderma harzianum enhances action against Foc TR4 in GCTCV 218, the moderately resistant somaclone.

Based on current studies, the combination of vesicular-arbuscular mycorrhiza (VAM) and T. harzianum works best in lowering Foc TR4 incidence. GCTCV 219, which is very resistant to Foc TR4, no longer requires application of microbial agents but should be properly managed.

Since 1999, the University of the Philippines Los Baños has been working on the development of BBTV-resistant lakatan.

Mutant lines were developed through irradiation and have shown intermediate resistance to BBTV. Disease spread was observed to be slower in lakatan lines compared to ordinary lakatan.

The performance of the lines are being tested in Quirino, Laguna, Batangas, and Davao City and shows varying performance across location: 270-405 days to harvest, six to nine hands per bunch, and 12-26 kg per bunch.