Integrating resistance management and biological control: parasitism and behavior of Telenomus remus Nixon, 1937 (Hymenoptera: Scelionidae) on Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) resistant to Vip3Aa20

• Grant number: 23/09661-1
• Support Opportunities: Scholarships in Brazil - Support Program for Fixating Young Doctors
• Start date: August 01, 2023
• End date: April 28, 2024
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Agreement: CNPq
• Principal Investigator: José Roberto Postali Parra
• Grantee: Aline Sartori Guidolin
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated research grant: 23/01240-7 - Integrating resistance management and biological control: parasitism and behavior of Telenomus remus Nixon, 1937 (Hymenoptera: Scelionidae) on Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) resistant to Vip3Aa20, AP.R

Abstract

The use of transgenic plants expressing insecticidal Bacillus thuringiensis (Bt) proteins and biological control are two compatible tools for integrated pest management, which reduce the use of insecticides. The fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae), is important due to its wide distribution and polyphagy. This insect pest has been difficult to control because of the resistance to insecticides from different chemical groups and Bt plants. Currently, one of the few proteins that control S. frugiperda is Vip3Aa, expressed in both maize and cotton Bt. The resistance of S. frugiperda to Vip3Aa20 in maize was characterized as autosomal and recessive, and the frequency of alleles that confer resistance to this protein is still low in Brazil. However, with the increasing use of Bt technologies expressing this protein, resistance management strategies must be implemented. The use of natural enemies has the potential for the management of S. frugiperda, particularly with the egg parasitoid Telenomus remus Nixon, 1937 (Hymenoptera: Scelionidae). However, there is a lack of studies on the interaction of the egg parasitoid and resistant hosts. The goal of this research is to evaluate the parasitism and the behavior of T. remus in resistant, susceptible, and heterozygous strains of S. frugiperda resistant to Vip3Aa20, as there is a gap in knowledge in both using egg parasitoids, and Vip3Aa. T. remus is expected to alter the population density of one specific genotype of S. frugiperda, which impacts the frequencies of resistance alleles. This research will advance the integration of biological control and resistance management.