ABSTRACT
Helicoverpa gelotopoeon is an endemic pest of South America that affects soybean and other important crops. Life tables are a fundamental tool used to study insect populations, resulting in crucial information for integrated pest management programs. Therefore, the aim of this study was to evaluate the biotic potential and the construction of a life table of this species under laboratory conditions. The biological parameters that showed significant differences between male and female were pupal duration, longevity and life span, which were all longer in duration for males. The net reproductive rate (R0) was 95.49, the mean generation time (T) 37.53, and the instantaneous rate of population increase "r" 0.12. The population doubling time (DT) was 5.70 days, and the daily finite rate of increase (λ) 1.13. The maximum rate of population growth occurred in the day 33. Fecundity had two peaks: at days 35 and 37. Gross and net fecundity rate, and the average number of eggs laid per female per day were 565.87, 496.07, and 18.76 respectively. The biotic potential was 2.026 x 1018 individuals/female/year. The survivorship curve showed that mortality was high during incubation period and first larval instars, then it declined until the death of last adult. These results provide important information to develop management strategies of H. gelotopoeon in South America.
Subject(s)
Life Cycle Stages/physiology , Life Tables , Moths/physiology , Animals , Female , Fertility/physiology , Larva/growth & development , Male , Moths/growth & development , Pupa/growth & development , Reproduction/physiologyABSTRACT
Chlosyne lacinia saundersii is one of the most important pests of sunflower and it is the main target of insecticides applications. Larvae were collected in Londrina (PR), Santa Maria (RS), Dourados (MS), Ribeirão Preto (SP), Brasília (DF), Barreiras (BA), Uberaba (MG) and Vilhena (RO). Genomic DNA was extracted and amplified with ten-mer primers, which produced 101 loci. The size of the RAPD amplicons ranged from 180 to 2564 bp. Polymorphism among populations ranged from 31% to 67%, with the highest polymorphisms of 57% and 67% being detected in Uberaba and Vilhena populations, respectively. Populations with the highest similarity determined with Dice coefficient were from Ribeirão Preto and Barreiras, while insects from Londrina showed the highest similarity among them. Gene flow of C. lacinia saundersii 1.1 was lower than those previously observed for the noctuid Anticarsia gemmatalis Hübner, suggesting that C. lacinia saundersii populations are more isolated than the ones of this noctuid. Through the Analysis of Molecular Variance (AMOVA), RAPD variance was 33.64% among geographical populations and 66.36% within populations. These results suggest that populations of C. lacinia saundersii are genetically structured.
Subject(s)
Genetic Variation/genetics , Helianthus/parasitology , Lepidoptera/genetics , Animals , Brazil , Genetic Markers/genetics , Lepidoptera/classification , Phylogeography , Random Amplified Polymorphic DNA Technique , Species SpecificityABSTRACT
Chlosyne lacinia saundersii is one of the most important pests of sunflower and it is the main target of insecticides applications. Larvae were collected in Londrina (PR), Santa Maria (RS), Dourados (MS), Ribeirão Preto (SP), Brasília (DF), Barreiras (BA), Uberaba (MG) and Vilhena (RO). Genomic DNA was extracted and amplified with ten-mer primers, which produced 101 loci. The size of the RAPD amplicons ranged from 180 to 2564 bp. Polymorphism among populations ranged from 31 percent to 67 percent, with the highest polymorphisms of 57 percent and 67 percent being detected in Uberaba and Vilhena populations, respectively. Populations with the highest similarity determined with Dice coefficient were from Ribeirão Preto and Barreiras, while insects from Londrina showed the highest similarity among them. Gene flow of C. lacinia saundersii 1.1 was lower than those previously observed for the noctuid Anticarsia gemmatalis Hübner, suggesting that C. lacinia saundersii populations are more isolated than the ones of this noctuid. Through the Analysis of Molecular Variance (AMOVA), RAPD variance was 33.64 percent among geographical populations and 66.36 percent within populations. These results suggest that populations of C. lacinia saundersii are genetically structured.
Chlosyne lacinia saundersii é uma das mais importantes pragas da cultura do girassol e o principal alvo das aplicações de inseticidas. As larvas foram coletadas em Londrina (PR), Santa Maria (RS), Dourados (MS), Ribeirão Preto (SP), Brasília (DF), Barreiras (BA), Uberaba (MG) e Vilhena (RO). O DNA genômico foi extraído e amplificado com dez primers, que produziram 101 locos. O tamanho das amplificações de RAPD variou de 180 a 2564 pb. O polimorfismo entre as populações variou de 31 por cento a 67 por cento, com maior polimorfismo 57 por cento e 67 por cento, detectado em populações de Uberaba e Vilhena, respectivamente. As populações com maior similaridade determinada com o coeficiente de Dice foram de Ribeirão Preto e Barreiras, enquanto os insetos coletados em Londrina apresentaram maior similaridade entre eles. O fluxo gênico de C. lacinia saundersii de 1,1 foi menor que o observado para a Anticarsia gemmatalis Hübner Noctuidae, sugerindo que as populações de C. lacinia saundersii estão mais isoladas do que estes noctuideos. Através da análise de variância molecular (AMOVA), RAPD a variação foi de 33,64 por cento entre as populações geográficas e 66,36 por cento dentro das populações. Estes resultados sugere que as populações de C. lacinia saundersii são geneticamente estruturadas.
