Fiji disease

Systematic position and pathogen nature: Fiji disease is caused by the Fiji disease virus (FDV), a member of the genus Fijivirus within the Reoviridae family. It is a double-stranded RNA virus that specifically targets members of the Poaceae family, leading to systemic physiological disturbances.

Host plants and disease symptoms: The primary host is sugarcane (Saccharum officinarum). Infected plants exhibit stunted growth, excessive leaf production, and characteristic galls (tumors) on the underside of leaves and stems. These symptoms result from the virus interfering with the hormonal balance of the plant tissues.

Biology and life cycle: The virus is transmitted in a persistent, circulative manner by the planthopper Perkinsiella saccharicida. Once a hopper ingests the virus from an infected plant, it remains infectious for the rest of its life cycle. The virus replicates within the insect's body before being transmitted to healthy sugarcane hosts.

Conditions for development: The spread of the disease is highly dependent on the population dynamics of its vector. Warm, humid climates encourage the proliferation of Perkinsiella populations. Furthermore, the disease is frequently introduced to new areas through the transport of infected vegetative cuttings used for planting.

Damage and control measures: Fiji disease causes severe yield losses by reducing cane quality and weight. Integrated management includes using certified, virus-free planting material, rigorous roguing of infected stools, control of planthopper populations through cultural or chemical methods, and the cultivation of resistant or tolerant sugarcane varieties.