1080 © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com Plant–Insect Interactions Plant Flavonoid Content Modified by Domestication Manuel Chac � on-Fuentes, 1,2 Leonardo Parra, 2,3,4 Marcelo Lizama, 2,3 Ivette Seguel, 5 Alejandro Urz � ua, 6 and Andre ´ s Quiroz 2,3,7 1 Doctorado en Ciencias de Recursos Naturales, Universidad de La Frontera, Av. Francisco Salazar 01145, Temuco, Chile (m.chacon01@ufromail.cl), 2 Laboratorio de Qu � ımica Ecol � ogica, Departamento de Ciencias Qu � ımicas y Recursos Naturales, Universidad de La Frontera, Av. Francisco Salazar 01145, Casilla 54-D, Temuco, Chile (leonardo.parra@ufrontera.cl; marcelo.lizama@ufrontera.cl; andres.quiroz@ufrontera.cl), 3 Centro de Investigaci� on Biotecnol� ogica Aplicada al Medio Ambiente (CIBAMA), Universidad de La Frontera, Av. Francisco Salazar 01145, Casilla 54-D, Temuco, Chile, 4 Scientific and Technological Bioresources Nucleus, BIOREN –UFRO, Universidad de La Frontera, Temuco, Chile, 5 Instituto de Investigaciones Agropecuarias, Centro Regional de Investigaci� on Carillanca, Temuco, Chile (iseguel@inia.cl), 6 Laboratorio de Qu � ımica Ecol� ogica, Departamento de Ciencias del Ambiente, Universidad de Santiago de Chile, Av. Bernardo O’ Higgins 3363, Santiago, Chile (alejandro.urzua@usach.cl), and 7 Corresponding author, e-mail: andres.quiroz@ufrontera.cl Subject Editor: Heather McAuslane Received 23 November 2016; Editorial decision 23 June 2017 Abstract Plant domestication can modify and weaken defensive chemical traits, reducing chemical defenses in plants and consequently their resistance against pests. We characterized and quantified the major defensive flavonols and isoflavonoids present in both wild and cultivated murtilla plants (Ugni molinae Turcz), established in a com- mon garden. We examined their effects on the larvae of Chilesia rudis (Butler) (Lepidoptera: Arctiidae). Insect community and diversity indices were also evaluated. We hypothesized that domestication reduces flavonoid contents and modifies C. rudis preference, the insect community, and diversity. Methanolic extracts were obtained from leaves of U. molinae plants and analyzed by high performance liquid chromatography. Results showed higher insect numbers (86.48%) and damage index (1.72 6 0.16) in cultivated plants. Four new first records of insects were found associated with U. molinae. Diversity indices, such as Simpson, Shannon, and Margalef, were higher in cultivated plants than in wild plants. Furthermore, eight isoflavonoids were identified in U. molinae leaves for the first time. The five flavonols showed higher concentrations in wild U. molinae leaves (89.8 mg/g) than in cultivated plants (75.2 mg/g); however, no differences were found in isoflavonoids be- tween wild and cultivated plants. The larvae of C. rudis consumed more leaf material of cultivated plants than wild plants in choice (3.8 vs. 0.8 mm 2 ) and no-choice (7.5 vs. 3.0 mm 2 ) assays. Our study demonstrates that do- mestication in U. molinae reduces the amount of flavonoids in leaves, increasing the preference of C. rudis and the insect community. Key words: domestication syndrome, chemical defense, flavonol, isoflavonoid Plant domestication is a process in which plants are modified so that they allocate their nutrients to accentuate production or some feature than defense according to human needs. In this framework, selection and breeding to achieve high-yielding plants has been a priority for farmers (Cock et al. 1979, Peng et al. 1999). Artificial selection is a prin- cipal factor in this process (Bautista et al. 2012). However, anthropo- genic improvements can generate a decrease in other physiological traits. Crop domestication has led to a decrease in the content of sec- ondary metabolites associated with resistance; to date, variations have been found in the levels of secondary metabolites in a subset of 203 dif- ferent species of domesticated crops, according to Meyer et al. (2012). Hammer (1984) proposed that this change in nutrient allocation within the plant (domestication syndrome) could be a useful tool for studying the trade-off between biomass production and secondary metabolites in the plant domestication process. Research into do- mestication and its consequences in plants with high or low degrees of domestication (Clement 1999) has been important for linking in- formation related to pest management or breeding programs in the field as well as for developing a new understanding of yield, defenses, and insect–plant interactions. Furthermore, changes in sec- ondary metabolism are not the only unintended results of domesti- cation. Community composition in plants can be indirectly affected by plant domestication (Rosenthal and Dirzo 1997, Chen and Bernal 2011, Chen et al. 2013). Secondary metabolites are involved in the feeding, oviposition choice, feeding behavior, development time, and developmental success of insects (War et al. 2012), and Research Environmental Entomology, 46(5), 2017, 1080–1089 doi: 10.1093/ee/nvx126 Advance Access Publication Date: 21 July 2017 Research Downloaded from https://academic.oup.com/ee/article/46/5/1080/4004769 by guest on 05 July 2022