Genetic parameters and selection of sugarcane for borer resistance in the advanced selection stage

Adriano Cirino Tomaz,Luiz Alexandre Peternelli,Marcos Deon Vilela De Resende,Mateus Teles Vital Gonçalves,Bruno Portela Brasileiro,Márcio Henrique Pereira Barbosa

doi:10.1590/1984-70332020v20n1a13

Abstract

Abstract This study aimed to investigate genetic parameters and selection strategies for sugarcane resistance to borer and determine the effects of selection for borer resistance on yield traits. The infestation index by borer (IIB) and yield traits were assessed over 3 years in 35 sugarcane clones planted in four locations in southeastern Brazil. There was no genotype × environment (year or location) interaction for borer resistance. Consequently, selection may be performed at only one location and year or by the mean of clones in several locations and/or years. The borer population affected the genotypic variance for borer resistance but when genotypic variance was significant, heritability was elevated and suitable genetic gain was achieved. Selection for borer resistance reduced the genetic gains for tons of cane per hectare, theoretical recoverable sugar, and tons of sugar per hectare; however, satisfactory selection gains for both borer resistance and yield were achieved using selection index.

Highlights

Brazil is the world’s largest sugarcane producer
Genetic parameters and comparison of selection scenarios for borer resistance The mean infestation by borer varied among years (11.54, 4.14, and 6.75% of bored internodes, respectively, in 2015, 2016, and 2017), which was likely related to environmental factors
The natural infestation pressure by the borer had a significant effect on the assessment of genetic variability in the population for borer resistance and on the experimental precision

Summary

Introduction

Brazil is the world’s largest sugarcane producer. The sugarcane crop area in the country covers nearly 8.38 million hectares and sugarcane production during the 2019/20 agricultural year is estimated at 622.3 million tons. (Lepidoptera: Crambidae) is one of the major pests of sugarcane in Brazil and causes severe yield losses across the country (Francischini et al 2017). It enables the entrance of fungus that causes red rot disease, which reduces both sugar yield and quality (Tomaz et al 2017). This pest is managed using biological control with larval endoparasitoid Cotesia flavipes and egg parasitoid Trichogramma galloi. The use of chemical insecticides has increased (Simões et al 2015, Valente et al 2018)

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Conclusion