Ecology, Behavior and Bionomics First Genotyping of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) Progeny from Crosses between Bt-Resistant and Bt-Susceptible Populations, and 65-Locus Discrimination of IsofamiliesArias RS1,5, Portilla M2*, Ray JD3, Blanco CA2,4, Simpson SA5, Sch Effler BE5
- *Corresponding Author:
- Portilla M
USDA-ARS Southern Insect Management Research Unit, 141 Experiment Station Road, Stoneville, MS 38776, USA
E-mail: [email protected]
Received date: 02/03/2015; Accepted date: 01/04/2015; Published date: 07/04/2015
Concerns exist that Bt-resistant populations of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) found in Puerto Rico, could spread to continental United States, and about the lack of molecular tools to monitor potential crosses or distinguish populations. In this work, the feasibility of genotyping S. frugiperda crosses between Bacillus thuringiensis (Berliner) (Bacillales: Bacillaceae) (Bt) resistant and susceptible populations using simple sequence repeats (SSRs, or microsatellites) was assessed. Parents and their corresponding progeny (five resistant, five susceptible phenotype) were genotyped using 192 SSRs on three reciprocate crosses alternating male and female from Bt-susceptible and Bt-resistant populations. Oviposition, mortality and fecundity were evaluated for five pairs of each of the crosses. Cluster analysis showed that progeny of each cross was associated with the paternal and not the maternal genotype, probably due to higher heterozygosity in male parents compared to females. Seven SSR markers had one or more alleles correlated (p≤0.002) with the Bt-resistant phenotype, and 18 SSRs showed uniparental inheritance. Analysis of additional samples showed genetic differences among isofamilies of S. frugiperda at 65 loci. The best 35 markers that discriminated isofamilies are reported, three of them related to components of the communication system in moths: pheromone, olfactory receptor and antennal esterase. This is the first report of: 1) a multi-locus genotyping in crosses of Btresistant and susceptible individuals of S. frugiperda, 2) seven codominant markers associated to Bt-resistance in this species, 3) discrimination of isofamilies by genetic differences at three loci that could affect the behavior of S. frugiperda.