Selection of Diploid and Tetraploid Banana Hybrids Resistant to Pseudocercospora fijiensis

Zalmar Santana Gonçalves,Fernando Haddad,Vanusia Batista De Oliveira Amorim,Edson Perito Amorim,Claudia Fortes Ferreira,Anelita De Jesus Rocha

doi:10.3390/agronomy11122483

Zalmar Santana Gonçalves, Fernando Haddad + Show 4 more

Open Access

https://doi.org/10.3390/agronomy11122483

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Abstract

Black Sigatoka, a disease caused by the fungus Pseudocercospora fijiensis, can lead to the complete loss of banana and plantain production in the absence of chemical control. The development of resistant cultivars is the focus of many banana breeding programs and is an alternative to the use of fungicides. In order to define a refined method of selection in genetic breeding programs, this study evaluated 23 improved diploids, seven tetraploids, and two commercial cultivars in the presence of P. fijiensis. Four selection criteria were considered: means of the disease severity index (ID) and area under the disease progress curve (AUDPC) estimated over the total period of the experiment, only in summer, only in winter, and the emission and harvesting of bunches. The selection of genotypes was more effective in the winter, and the evaluation of four leaves no. 3 emitted after six months of growth was efficient at differentiating the resistant and susceptible genotypes. For the improved diploids and tetraploid hybrids, DI varied from 0.0 to 48.8 and from 15.1 to 63.5, respectively, and the AACPD for the improved hybrids and tetraploid hybrids varied from 0.0 to 2439.5 and 1000.2 to 3717.7, respectively. The tetraploid hybrid of the Prata-type CNPMF0906 and the commercial cultivar, which is a hybrid of the BRS Princesa Silk type, showed quantitative resistance and can be used by banana producers. Results suggest that the guidelines adopted for the selection of genotypes resistant to black Sigatoka may include methodologies that reduce the evaluation time. In addition, new sources of resistance to the disease and the influence of its genetic inheritance in future crosses were found.

Highlights

Bananas and plantains are cultivated in tropical and subtropical regions of 150 countries, and are among the four most important foods in the world [1]
It can be inferred that the most efficient way to differentiate genotypes in the resistant, moderately resistant, and susceptible classes is to evaluate the symptoms of P. fijiensis during the winter season
Higher mean values were observed in the DI and area under the disease progress curve (AUDPC) for the evaluations made in the winter

Summary

Introduction

Bananas and plantains are cultivated in tropical and subtropical regions of 150 countries, and are among the four most important foods in the world [1]. The world’s banana production was more than 114 million tons and plantains exceeded 40 million in 2018, cultivated in a total area of approximately 11 million hectares. Some diseases are responsible for significant losses in the production of bananas and plantains, notably black Sigatoka, caused by Pseudocercospora fijiensis (sexual form: Mycosphaerella fijiensis) [5]. This fungus was described in 1963 on the islands of Fiji [6]

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