title: Screening of Potential Sources of Resistance to Spodoptera exigua (Lepidoptera: Noctuidae) in 24 Sugar Beet Genotypes.
abstract: Spodoptera exigua (Hübner) is one of the polyphagous pests destroying crops such as sugar beet worldwide. The aim of this experiment was to evaluate the resistance of 24 sugar beet genotypes to S. exigua. In this study, nine sugar beet cultivars (Dorotea, Tous, Persia, Silenta, Jaam, HM1339RZ, Jolgeh, Ekbatan, and SBSI006), three hybrids ((7112*SB36)*Sh-1-HSF-5, (7112*SB36)*Sh-1-HSF-15, and (7112*SB36)*Sh-1-HSF-16), four lines (FC201, FC301, FC220, and FC221), and eight populations (SB26, SB27, SB28, SB29, SB30, SB33, SB34, and SB35) were assessed. The experiments were performed under laboratory conditions at 25 ± 1 °C, 60 ± 5% RH, and a photoperiod of 16:8 (L:D) h using age-stage, two-sex life table procedure. The larval period ranged from 17.09 d on FC301 to 14.47 d on SB30. The total fecundity (F) was highest on (7112*SB36)*Sh-1-HSF-5 (905.13 eggs) and lowest on FC301 (312.46 eggs). (7112*SB36)*Sh-1-HSF-5 and FC220 with 318.02 and 26.76 eggs per individual had the highest and lowest net reproductive rates (R0), respectively. The highest values of the intrinsic rate of increase (r) and finite rate of increase (λ) were on (7112*SB36)*Sh-1-HSF-5 (r: 0.187 d - 1, λ: 1.205 d - 1) and the lowest were on FC301 (r: 0.104 d - 1, λ: 1.11 d - 1). SB26 (r: 0.185 d - 1, λ: 1.203 d - 1) and FC220 (r: 0.114 d - 1, λ: 1.12 d - 1) had no significant difference with (7112*SB36)*Sh-1-HSF-5 and FC301, respectively. The comparison of demographic parameters of S. exigua on 24 sugar beet genotypes suggested that FC220 and FC301 were the most resistant and (7112*SB36)*Sh-1-HSF-5 and SB26 were the most susceptible genotypes to this pest.
authors.affiliation: Department of Entomology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran.
authors.forename: Ladan
authors.initials: L
authors.lastname: Talaee
authors.affiliation: Department of Entomology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran.
authors.forename: Yaghoub
authors.initials: Y
authors.lastname: Fathipour
authors.affiliation: Department of Entomology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran.
authors.forename: Ali Asghar
authors.initials: AA
authors.lastname: Talebi
authors.affiliation: Department of Plant Protection, College of Agriculture, Isfahan University of Technology, Isfahan, Iran.
authors.forename: Jahangir
authors.initials: J
authors.lastname: Khajehali
mesh_terms: D000818:Animals; D000898:Antibiosis; D027461:Beta vulgaris / Q000235:genetics / Q000502:physiology*; D005838:Genotype; D007814:Larva / Q000235:genetics / Q000502:physiology; D015993:Life Tables; D012098:Reproduction; D018411:Spodoptera / Q000254:growth & development / Q000502:physiology*
keywords:  beet armyworm; Spodoptera exigua; resistance; sugar beet genotype; two-sex life table