Isolation and Characterization of Microsatellite Markers for Soybean Looper (Lepidoptera: Noctuidae)

Abstract

We constructed 13 microsatellite markers for Chrysodeixis includens (Walker), a serious crop pest in the Americas. All SSR (Simple Sequence Repeat) markers were polymorphic, with no evidence of linkage disequilibrium between any loci in any population. The total number of alleles per locus ranged from 5 for L3, L9, and L11 to 26 for L6; the mean number of alleles per locus in three populations of C. includens ranged from 2.33 for L3 to 14.67 for L6. Hardy–Weinberg equilibrium (HWE) deviation was not observed in four loci for at least one population (L3, L5, L9, L10). Markers L6, L7, L8, L10, L11, L12, and L13 showed a frequency of null alleles > 0.2 for at least one population. STRUCTURE and F-statistics revealed low population structure among the populations (FST = 0.013) and a high degree of inbreeding (FIS = 0.658). The SSR markers developed here will be useful in future studies on the ecology, demography, host dynamics, and gene flow of C. includens. This information is essential to understand the recent status of C. includens as a key pest in South America.

Development of microsatellite markers and genetic diversity of the velvetbean caterpillar Anticarsia gemmatalis (Lepidoptera: Erebidae)

“…As individuals of the species are easily dispersed, it is more likely that the null alleles (average 0.12) are altering the proportion of homozygotes in the studied populations. A high frequency of null alleles seems not to be exclusive to VBC, because it is apparently higher in lepidopterans compared with other insect orders (Ji et al 2003), as it can be seen in several other studies (Endersby et al 2007; Leite et al 2017; Pavinato et al 2013; Reineke et al 2021; Silva et al 2019; Sinama et al 2011; Song et al 2017), a fact that may be associated with the high mutation rates of SSR markers in this order (Dakin & Avise 2004). As a consequence of the presence of these alleles, a decrease is observed in the estimates of heterozygotes in the population, resulting in the overestimation of inbreeding values and deviations from the Hardy–Weinberg equilibrium (Pemberton et al 1995).…”

“…The markers here developed led to the identification of 134 alleles, with an average of 14.9 alleles per locus, a number higher than that observed in Spodoptera frugiperda (J.E. Smith, 1797), that is, an average of 10.8 (Pavinato et al 2013), and in C. includens , with an average of 12.9 alleles per locus (Silva et al 2019). In addition, the genotypic accumulation curve (Figure 1), showing the identification of 100% of the multilocus genotypes, with only five of the nine primer pairs tested, and the high values of PIC (average = 0.73), demonstrated the efficiency of the markers developed to identify individuals and estimate the genetic diversity indices of VBC.…”

De Novo Mining and Validating Novel Microsatellite Markers to Assess Genetic Diversity in Maruca vitrata (F.), a Legume Pod Borer

“…Seven loci deviated significantly from HWE. The presence of HWE and alleles are pervasive in SSR studies of lepidopteran species [14,47,56]. The higher frequency of a null allele in Lepidoptera is due to the higher frequency of mutation in the flanking region because of transposable elements [57,58].…”

“…These results suggest the communication of genetic information between different populations of Indian M. vitrata. A lack of genetic structure due to high migration rate has been demonstrated in several other insect species, including Plutella xylostella from China [8,62], Korea [63], USA [64,65], and Oceania (Australia and New Zealand) [66]; Mythimna separata from China [67]; Chrysodeixis includes from Brazil [56]; and Argyresthia conjugella from the Scandinavian Peninsula [68].…”