AN organic solution has been proven effective against the dreaded banana “crown rot” disease that spoils up to 20 percent of banana shipments from the Philippines, and is a safer alternative than chemical treatments, the Philippine Center for Postharvest Development and Mechanization (PhilMech) reported.
The finding was the result of tests carried out by PhilMech in cooperation with Visayas-based banana exporter Alter Trade Corporation (ATC).
For more than 27 years since the 1980s, ATC has been shipping organically grown “bungulan” bananas to Japan, with recent volumes averaging 2,800 boxes per week and 4,000 boxes during the peak season.
ATC currently has more than 3,000 partner-households in Negros Occidental alone, and has expanded its operations to Cebu, Panay, Bohol and even Nueva Vizcaya.
However, banana exporters in the Philippines like ATC have to continuously deal with the dreaded banana crown rot, which can result in bananas being thrown away literally upon arrival at the export markets.
In the case of ATC, 7 percent to as high as 20 percent of shipments become infected by banana crown rot. The infection takes place during shipment that usually last from 25 to 30 days.
According to PhilMech, an agency under the Department of Agriculture, some agribusiness companies pre-treat their banana shipments with chemicals that are effective against crown rot, but can have negative implications to human health.
Rejection rates reduced
Fortunately, PhilMech has an organic solution to deal with the banana crown rot, particularly two species of epiphytes—Bacillus spp. strain DGA14 and Trichoderma spp. strain DGA02—that were both proven effective as microbial control agents (MCAs) in combating the crown rot disease.
Based on tests conducted by PhilMech on ATC shipments, the rejection rate for bananas bound for the export market can be brought down to as low as 1.5 percent using MCA-formulated dip treatment.
“With our findings, what PhilMech can explore is to commercialize the use of the technology and conduct trials on other tropical fruits like mango that are bound for the export market,” said Dr. Dionisio Alvindia, the new Executive Director of PhilMech.
The MCA-tap water ratio used for the biocontrol spray was about 1:13.
During the first trial using MCA-formulated treatment, the rejection rate was 1.5 percent 29 days after treatment (DAT), meaning the pathogens causing the banana crown rot disease were kept in check for almost a month.
The researchers also monitored three factors, namely, crown rot index (0-7 where 0 means disease-free), visual quality (1-6 where 6 denotes excellence) and peel color (0-7 where 7 means yellow).
The bananas treated with MCA-formulated spray recorded a crown rot index at a very low 0.6 for DGA14 and 0.475 for DGA02. In visual quality, the rating was 5.0 and 4.75 for DGA14 and DGA02, respectively. When it came to peel color, the DGA14-treated bananas rated at 5.0 and DGA02-treated at 4.75.
ATC president Gilda Caduya said the use of MCA-formulated spray could help the company increase its earnings.
“Addressing crown rot would mean increased profit rate for ATC, then we can have the budget for our social projects for our partner-communities,” she said.
PhilMech also has conducted notable studies on botanicals as protective spray against storage pests like grain weevils and borers. Among them were ikmo leaves, jathropa, neem and atis seeds.
Dr. Alvindia led the field trials with ATC when he was the principal researcher of the Biological Control Agents Project of PHilMech. His colleague Elijah Davalos participated in the field tests.
Dr. Alvindia has two patents for his findings on MCA namely, the bacteria Bacillus amyloliquefaciens, and fungi Trichodermaharzianum, which can be used to control banana crown rot.
The crown rot disease starts from the tissues where the banana cluster was cut, spreads to the whole cluster and destroys the whole commodity.