AZEREDO-ESPIN, A. M. L.

BERGAMO, L. W.

MASTRANGELO, T.

MORAIS, E. G. F. de

PAULO, D. F.

SILVA, M.

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1Centro de Biologia Molecular e Engenharia Genética (CBMEG), UNICAMP, Campinas-SP2EMBRAPA Roraima, Boa Vista-RR3Universidade Estadual do Piauí (UESPI), Uruçuí-PImastrangelo@cbmeg.unicamp.brTÍTULO DO RESUMOThiago Mastrangelo1; Daniel F. Paulo1; Luana W. Bergamo1; Elisangela G. F. de Moraes2;  Márcio Silva3 & Ana M. L. Azeredo-Espin1ANALYSIS OF THE GENETIC DIVERSITY AND STRUCTURE OF Helicoverpa armigera POPULATIONS FROM NORTH AND NORTHEAST OF BRAZILINTRODUCTIONMATERIAL and METHODSThe cotton bollworm, Helicoverpa armigera (Hübner), was recentlyintroduced in Brazil. During the 2012/2013 harvest, producers reportedreduced yields up to 35% on major crops. Most producers increased thenumber of pesticide applications in more than 15%, and the costs in cottonfields, for example, jumped from US$ 400 to US$ 800 per hectare.The extensive economic losses reached US$ 1 billion until July 2013only in Western Bahia, triggering a phytosanitary crisis. So far, the exactdistribution and extension of economic damages of this exotic pest in Brazilis still not known.This study aimed to explore the genetic diversity and populationstructure of three populations of this heliothine invader that were foundinfesting crops in the states of Roraima, Piauí and Bahia.A total of 65 H. armigera larvae were collected from infested farms from RESULTS and DISCUSSION Figure 1. Genetic diversity and distribution of haplotypes from 3 Helicoverpa armigera populations.the states of Roraima (n=14), Piauí (n=39), and Bahia (n=12). Larvae werecollected directly from host plants and preserved in 100% ethanol at -20 ºC.Total DNA was extracted from the last three abdominal segments of thelarvae using the phenol: chloroform method, modified by Lyra et al. (2009).Partial sequences of the COI and COII genes were amplified using theprimers described by Li et al. (2011) and Liu & Beckenbach(1992), followingthe PCR conditions described by Li et al. (2011).Amplicons were sequenced by the ABI3730xl DNA Analyzer. Sequenceswere aligned through the algorithm implemented in Clustal Ω. Haplotypefrequencies, haplotype diversity (Ĥ) and nucleotide diversity (π) wereestimated using Arlequin v.3.5 software. Genetic differences betweenpopulations were determined through pairwise FST statistics.The COI and COII fragments from the 65 specimens from Roraima,Piauí and Bahia were concatenated, generating a final 1212 bpsequence for each individual, and a total of 22 different haplotypeswere defined (Figure 1).Many haplotypes were shared among the three Brazilian states,suggesting a significant gene flow among these regions. In general,high haplotype diversity (Ĥ-mean > 0.85) and low nucleotide diversity(π-mean < 0.003) were observed for the locations analyzed. In general,this scenario is characteristic of species that have undergone aprocess of recent population expansion.AMOVA detected no genetic structure (FST = 7.10-5, P = 0.44), with99.9% of variation accounted for at the within population level andwith only 0.01% variation observed among populations. Pairwise FSTvalues were low and not significant (FST < 0.03; P > 0.05),demonstrating that these populations are not structured (Table 1).ABI3730xl DNA Analyzer  sequencerTable 1. Pairwise FST estimates among three investigated heliothine populations from Brazilbased on combined genes COI and COII.IllustraTMGFXTM kit for purificationTotal DNA extraction by the Phenol: Chloroform  Method (Lyra et al. , 2009)CONCLUSIONS The invasive moth H. armigera is not restricted to crop fields from Northeastand Central Brazil, but has already crossed the Amazon basin.Surveys in Venezuela and Colombia should start as soon as possible inorder to monitor its entry or spread in Central America and the USA.The H. armigera larvae were collected from several crops and preserved in 100% ethanol. COI (658 bp) and COII (554 bp) Sequences

Analysis of the genetic diversity and structure of Helicoverpa armigera populations from North and Northeast of Brazil.

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