Genetic Variation of Beet Armyworm (Lepidoptera: Noctuidae) Populations Detected Using Microsatellite Markers in Iran

Abstract

In order to understand the population genetic diversity and structure of Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), a serious pest of sugar beet in Iran and the world, we genotyped 133 individuals from seven regions in Iran using four microsatellite loci. Significant difference was seen between the observed and expected heterozygosity in all loci. A lower observed heterozygosity than expected heterozygosity indicated a low heterozygosity in these populations. The value of F showed a high genetic differentiation, so that the mean of Fst was 0.21. Molecular analysis variance showed significant differences within and among populations with group variance accounted for 71 and 21%, respectively. No correlation was found between pair-wise Fst and geographic distance by Mantel test. Bayesian clustering analysis grouped all regions to two clusters. These data suggested that a combination of different factors, such as geographic distance, environmental condition, and physiological behavior in addition to genetic factors, could play an important role in forming variation within and between S. exigua populations.

Population genetics unveils large‐scale migration dynamics and population turnover of Spodoptera exigua

“…High levels of S. exigua ecological plasticity relate directly to this migration behavior and associated life history facets 25 . In the Northern Hemisphere, lepidopteran migration is routinely directed northward during spring and summer seasons 5,61,62 .…”

“…High levels of S. exigua ecological plasticity relate directly to this migration behavior and associated life history facets. 25 In the Northern Hemisphere, lepidopteran migration is routinely directed northward during spring and summer seasons. 5,61,62 Climate is a core determinant of migration; many noctuids are facultative migrants that rely upon wind patterns to alight under suitable environmental conditions.…”

“…Earlier work using amplified fragment length polymorphism (AFLP) and mitochondrial genes indicated low levels of genetic variation among distinct S. exigua populations and no clear phylogeographic structure 21–24 . By contrast, through the use of microsatellite DNA markers, two genetically distinct S. exigua groups were detected in Iran and western China 25,26 . However, as a consequence of outdated molecular markers, small sample sizes or (relatively) few survey sites, these studies have not captured the genetic composition of Asian S. exigua populations at a sufficiently fine resolution.…”

“…[21][22][23][24] By contrast, through the use of microsatellite DNA markers, two genetically distinct S. exigua groups were detected in Iran and western China. 25,26 However, as a consequence of outdated molecular markers, small sample sizes or (relatively) few survey sites, these studies have not captured the genetic composition of Asian S. exigua populations at a sufficiently fine resolution.…”

Insights into the origin of the invasive populations of Trioza erytreae in Europe using microsatellite markers and mtDNA barcoding approaches

“…Apart from mtDNA barcoding, nuclear markers such as the microsatellites (SSRs: S imple S equence R epeat s ) have been used widely, because of their extensive genome distribution and high level of polymorphism, to study the genetic diversity and phylogeography of several crop pest insects such the tomato leaf miner Tuta absoluta (Meyrick) 28 (Lepidoptera: Gelechiidae); the beet armyworm Spodoptera exigua (Hübner) 29 (Lepidoptera: Noctuidae); the sugar cane aphid Melanaphis sacchari (Zehntner) 30 (Hemiptera: Aphididae); the cotton mealybug Phenacoccus solenopsis (Tinsley) 31 (Hemiptera: Pseudococcidae); the whitefly Bemisia tabaci (Gennadius) 32 32 (Hemiptera: Aleyrodidae); as well as the Asian citrus psyllid D. citri 33 , 34 . The main objective of the present work is to gain insights in the genetic structure of the T. erytreae populations, as very little is known about their genetic traits.…”