Millions of people worldwide rely on banana as a staple food and cash crop. Banana is ranked the fourth most important food crop after wheat, rice, and corn in the developing word.

The total banana production was 114 million tonnes in 2017, up from 67 million tonnes in 2000[1]. The global banana industry generates around USD 8 billion per year based on the recent export figure. However, it is important to note that only 15 percent of banana production is traded mainly to Europe and USA; the rest is consumed locally, most importantly in large producing countries such as India, China and Brazil, and in some African countries where bananas contribute largely to people’s diets.

A global threat

The emergence of the Tropical Race 4 (TR4) of the Fusarium wilt disease (hereafter referred to “Foc TR4”) poses a serious threat to banana production globally. The Foc TR4 mainly attacks the Cavendish banana known as the most planted and exported variety. However, other varieties of banana plant are also susceptible to this fungus strain.

The Foc TR4 is a soil-borne pathogen that attacks the roots of the plant and blocks its vascular system. It can be transmitted through planting materials, movement of infested soil particles through any means such as shoes, vehicles or through water (flooding).

The fungus is able to remain in the soil for more than 30 years. It is recognized as a serious threat to banana plantations because once it is established, it cannot be eliminated. The disease can't be controlled by common chemical or cultural management practices. Available methods for disease containment are not fully efficient on TR4; and alternative options are still at the evaluation stage. This fungus strain was first detected in the 1990s in Malaysia and Indonesia and quickly spread to China, where it occurs widely.

This race has been causing serious losses in Southeast Asia and severely affecting livelihoods of local populations and especially income opportunities for smallholder banana farmers.

The Foc TR4 is just around the corner

The Foc TR4 is not detected in Cambodia. However, the risk is getting higher and extra attention with better management of the disease is much needed since the Foc TR4 is already present in neighboring countries including Thailand, Vietnam, Myanmar, Lao PDR, and China.

To prevent the introduction and spread of Foc TR4 to Cambodia, the Food and Agriculture Organization of the United Nations (FAO) and the General Directorate of Agriculture (GDA) of the Ministry of Agriculture, Forestry and Fisheries (MAFF) has jointly implemented a technical cooperation project.

“The project aimed at building the capacity of the Plant Protection, Sanitary and Phytosanitary (PPSPS) department of the GDA on diagnostic and surveillance system of the banana Fusarium wilt disease in the country, as requested by the GDA,” as emphasized by Mr Oum Kosal, Assistant FAO Representative (Programme).

In Cambodia, smallholder farmers grow banana as a backyard crop and on a medium scale to fulfill the local demand. In 2017, about 39 000 hectares were planted with banana. Farmers could benefit from their plantation in an amount of around three to seven million Riel (USD 700 to USD 1 700) per hectare per year.

In recent years, the planting of banana has been rapidly expanding, thanks to foreign investments mostly, responding to a high demand on international markets, particularly China.

H.E. Dr Ngin Chhay, Director General of the GDA, informed the participants of a dissemination workshop held in Phnom Penh in late November 2019 that since the signing of the memorandum of understanding between Cambodia and China in late 2018, a total of 13 793.96 tons of yellow banana (Cavendish variety) were exported to China.

The expansion of banana plantation requires significant quantities of imported banana seedlings. Cavendish bananas, which account for about 90 percent of total banana exports, are planted in large-scale banana plantations. Importing banana seedlings and planting material from neighboring countries raises a high risk of introducing invasive species, especially the Foc TR4, which may cause the collapse of the industry. The Foc TR4 causes disease without predisposing factors. If unchecked, Fusarium caused by Foc TR4 can wipe out an entire plantation.

Preparedness is key: FAO’s support

With support from the project, Cambodian officials attended regional workshops on the molecular identification of Foc TR4, planning and operationalized the e-surveillance system. Following these regional trainings, Cambodia has strengthened its capacity and capability to identify Foc TR4. Over a hundred Foc suspected samples were all found negative to TR4.

Trainings were also conducted in the country for the surveillance teams to develop a national surveillance system, using new tools and technology (including e-forms and collection of data using P-tracker tablets). Surveillance activities have then been carried out in five selected provinces (Kampot, Kampong Cham, Banteay Meanchey, Preah Vihear and Ratanakiri) with higher risk of Foc TR4 presence.

Preparedness activities haven’t been forgotten. Cambodia has developed Foc TR4 national control strategies based on the sharing of information at the regional workshop. Another major achievement was the establishment of the Standard Operating Procedure (SOP) for managing Foc TR4 in Cambodia, which is now being translated in local language (Khmer) for wider dissemination.

To transfer appropriate control measures of the Foc TR4 to farmers, Farmer Field Schools[2] (FFS) were established in two villages involving about fifty farmers.

Moreover, in expanding transmission of this information and knowledge, two farmer field days were organized, involving more than 200 participants.

H.E. Dr Ngin Chhay strongly emphasized that the imported planting material needed to be free from Foc TR4 and that the PPSPS department had to use import quarantine control measures for banana planting material.

Considering that Cambodia has high potential for banana investment and with the ongoing rapid growth of banana production areas, H.E Dr Ngin Chhay also advised the department to take action now, by closely and regularly monitoring Foc TR4 if the disease is present (in the soil, for instance). Therefore, the outbreak control mechanism must be used to prevent the spread of the disease to new areas.

The project has come to an end. It concluded with a national dissemination workshop to share results and development achieved by the project in the banana value chain.  In this dissemination workshop, H.E. Dr Ngin Chhay emphasized that, “Foc TR4 is the most serious disease (threatening banana); Cambodia needs to work hard to protect banana production.” 

 [1] FAO: http://www.fao.org/economic/est/est-commodities/bananas/bananafacts/en/#.XgQ-7UczaUl