Banana Cultivar Field Screening for Resistance to Fusarium oxysporum f.sp. cubense Tropical Race 4 in the Northern Territory.

Sharl J. L. Mintoff,Samantha Cullen,Chris Kelly,Lucy T. T. Tran-Nguyen,Tuan V. Nguyen,Jeffrey W. Daniells,Robert Williams,Mark Hearnden

doi:10.3390/jof7080627

Abstract

Fusarium oxysporum f.sp. cubense, causal agent of Panama disease, is one of the biggest threats to global banana production, particularly the Cavendish competent tropical race 4 (Foc TR4). It continues to spread globally with detections occurring in regions of the Middle East and new continents such as Africa and South America in the last decade. As the search was on for new management strategies and resistant cultivars to combat the disease, a banana cultivar-screening trial took place in the Northern Territory of Australia, which examined the responses of 24 banana cultivars to the soil borne fungus. These cultivars included material from TBRI, FHIA and selections from Thailand, Indonesia and Australia and evaluated for their resistance to tropical race 4 for two cropping cycles. Several cultivars displayed considerable resistance to Foc TR4, including several FHIA parental lines and hybrids, the Cavendish (AAA) selections GCTCV 215 and GCTCV 247 from TBRI and an Indonesian selection CJ19 showed either very little to no plant death due to the disease.

Highlights

IntroductionCubense (Foc), poses a significant economic threat to banana production worldwide with its continued spread into banana growing regions
We report the findings of a Foc tropical race 4 (TR4) resistance screening trial conducted in the Northern Territory of Australia, which included 24 banana cultivars and breeding lines assessed for their resistance to Foc TR4 and agronomic data collected across two cropping cycles
Of the 24 cultivars tested in this trial, nine cultivars rated as highly resistant and did not succumb to Foc TR4 infection, with an additional four cultivars rated as resistant with minimal effects of the disease noted, which included Cavendish lines, FHIA lines and Pisang Gajih Merah

Summary

Introduction

Cubense (Foc), poses a significant economic threat to banana production worldwide with its continued spread into banana growing regions. This pathogen is not new to global banana production, as symptomology of Foc was first described in 1876 [1]. In the presence of a susceptible host plant, pathogen infection occurs through the lateral roots, from there the pathogen moves into the rhizome via the vascular tissue where the characteristic brown-maroon vascular discoloration can be observed as the infection progresses [2,3]. As the infection spreads into the outer leaf sheaths of the pseudostem, wilting and yellowing of the oldest leaves occurs, which will eventually progress to the younger leaves leading to the death of the plant [4,5]. The genetic diversity of Foc enabled this pathogen to infect a diverse range of bananas, and has been broadly categorised into four races based on their pathogenicity on particular banana cultivars [6,7]

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Conclusion