COMPARISON OF HOST REACTION TO FUSARIUM OXYSPORUM F. SP. CUBENSE TROPICAL RACE 4 AND AGRONOMIC PERFORMANCE OF SOMACLONAL VARIANT 'GCTCV-119' (AAA, CAVENDISH) AND 'GRAND NAINE' (AAA, CAVENDISH) IN COMMERCIAL FARMS IN THE PHILIPPINES

Abstract

The original publication is available at www.actahort.org. Recent reports of the occurrence of Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), causal agent of Fusarium wilt, in some commercial Cavendish banana plantations in the Philippines is of great concern to the Philippine banana industry. In an effort to mitigate the disease, 'GCTCV-119', a Foc TR4-resistant somaclonal variant of 'Giant Cavendish' selected by the Taiwan Banana Research Institute, was evaluated and compared with the commercial cultivar 'Grand Naine' in Foc-infested farms in Davao, Philippines. Isolates obtained from infected samples from these farms were previously typed as VCG1213/16, the vegetative compatibility group associated with TR4. Tissue culture-derived planting materials of 'GCTCV-119' and 'Grand Naine' were planted in randomised blocks in two farms where severe Fusarium wilt incidence was previously observed. After 12 months of disease incidence monitoring, 'GCTCV-119' showed no Fusarium infection, while 36 and 51% incidence was recorded for 'Grand Naine' in Calinan and Quibilan farms, respectively. Two years after establishment, 'GCTCV-119' plots in the Quibilan farm are still free from infection of Fusarium wilt while the 'Grand Naine' plots have been totally eradicated because of severe disease incidence. Agronomic and fruit quality traits were also recorded. Although 'GCTCV-119' proved to be highly resistant to TR4, it matured later and had a lower bunch weight and greater hand curvature resulting in more rejects when packed. 'GCTCV-119' is however sweeter as it has more total sugars and total soluble solids than 'Grand Naine'.