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Updated: Jul 27, 2025

Determination of Self- and Inter-incompatibility Relationships in Apricot Combining Hand-Pollination, Microscopy and Genetic Analyses
Published on: June 16, 2020
Reproductive compatibility among sympatric and allopatric isofemale lines of
Aloisio Coelho1, Jaci Mendes Vieira2, Paul F Rugman-Jones3
1Department of Entomology and Acarology, University of São Paulo (USP)/ Luiz de Queiroz College of Agriculture (ESALQ). Av. Pádua Dias, 11, Zip code: 13418-220, Piracicaba, SP, Brazil.
Abstract:
The present study evaluated the reproductive compatibility of Trichogramma pretiosum Riley, 1879, through an integrative approach using biological data and morphometry of three isofemale lines (isolines) collected from two geographical areas. These isolines differed in sequences of mitochondrial DNA and reproductive performance in the laboratory. The wasps used to initiate the isolines were collected in different environments: two lines from a Mediterranean climate in Irvine, California, USA, and one line from a tropical climate in Piracicaba, São Paulo, Brazil. Reproductive compatibility was studied by evaluating the sex ratio and number of adult offspring produced of all mating combinations between adults from these isolines. Morphometry was studied by measuring 26 taxonomically useful characters, followed by a multivariate analysis. For the allopatric matings among Brazilian and North American isolines, a low level of crossing incompatibility was recorded, in only one direction of the crosses; whereas the sympatric North American isolines were incompatible in both directions. Multivariate analysis of the morphometric data indicated no distinct groups, suggesting that despite the genetic and biological differences, the isofemale lines are morphologically similar.
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