vavilovВавиловский журнал генетики и селекцииVavilov Journal of Genetics and Breeding2500-3259Institute of Cytology and Genetics of Siberian Branch of the RAS10.18699/VJ18.425vavilov-1715Research ArticleГЕНОФОНД И СЕЛЕКЦИЯ РАСТЕНИЙPLANT GENE POOL AND BREEDINGАллельная и эпигенетическая вариация ДНК в связи с проявлением гетерозиса в F2 Capsicum annuum L.Allelic and epigenetic DNA variation in relation to F1 heterosis manifestation in F1 hybrids of Capsicum annuum L.https://orcid.org/0000-0003-4694-3197ШаптуренкоМ. Н.ShapturenkoM. N.

Минск

Minsk

marinashapturenko@gmail.comhttps://orcid.org/0000-0002-2242-7107ВакулаС. В.VakulaS. V.

Минск

Minsk

ТарутинаЛ. А.TarutinaL. A.

Минск

Minsk

https://orcid.org/0000-0002-3263-4732НикитинскаяТ. В.NikitinskayaT. V.

Минск

Minsk

ПечковскаяТ. В.PechkovskayaT. V.

Минск

Minsk

МишинЛ. А.MishinL. A.

Самохваловичи, Минская область

Samokhvalovichy, Minsk region

https://orcid.org/0000-0003-0295-5022ХотылеваЛ. В.KhotylevaL. V.

Минск

Minsk

Институт генетики и цитологии Национальной академии наук БеларусиБеларусьInstitute of Genetics and Cytology of the National Academy of Sciences of BelarusBelarusИнститут овощеводстваБеларусьInstitute of Vegetable GrowingBelarus201808112018227812819Copyright © Шаптуренко М.Н., Вакула С.В., Тарутина Л.А., Никитинская Т.В., Печковская Т.В., Мишин Л.А., Хотылева Л.В., 20182018Шаптуренко М.Н., Вакула С.В., Тарутина Л.А., Никитинская Т.В., Печковская Т.В., Мишин Л.А., Хотылева Л.В.Shapturenko M.N., Vakula S.V., Tarutina L.A., Nikitinskaya T.V., Pechkovskaya T.V., Mishin L.A., Khotyleva L.V.This work is licensed under a Creative Commons Attribution 4.0 License.https://vavilov.elpub.ru/jour/article/view/1715

Одна из основных задач селекции - получение гибридов с выраженным эффектом гетерозиса. При этом информация о генетическом разнообразии селекционного материала рассматривается как инструмент отбора перспективных комбинаций скрещивания, так как, согласно классической теории, гетерозиготность является основным фактором, обусловливающим превосходство гибридов F1 над родителями. В связи с этим предполагается наличие прямой зависимости между уровнем генетического полиморфизма исходных родительских форм и гетерозисом в поколении F1 их гибридов. Опубликованные к настоящему времени данные, направленные на поиск критериев прогнозирования гетерозиса у растений, показали разноречивые результаты В нашем исследовании мы изучили вклад структурного и неструктурного ДНК-полиморфизма в реализацию гетерозиса F1 у перца сладкого. Были использованы SSR- и метилчувствительный AFLP-протокол (MSAP с использованием изошизомеров HpaII и MspI) для выявления специфичных аллельных вариантов и эпигенетических паттернов у гетерозисных и негетерозисных гибридов перца сладкого, включенных в белорусскую селекционную программу. При изучении структурного полиморфизма ДНК с использованием микросателлитных маркеров обнаружено, что часть вариации в проявлении гетерозиса может быть объяснена полиморфизмом, который выявляется при SSR-анализе. Согласно нашим результатам, общее число полиморфных локусов и коэффициент соотношения полиморфных и мономорфных локусов могут служить дополнительным критерием отбора перспективных комбинаций скрещивания наряду с классическими методами селекции. При изучении эпигенетических модификаций ДНК, возникающих при гибридизации, была обнаружена тесная связь между статусом метилирования ДНК и гетерозисом для основных показателей продуктивности гибридов перца сладкого. Полученные результаты подтвердили предположение о том, что гибридизация способствует возникновению эпиаллельной вариации ДНК у гибридов первого поколения, которая может обусловливать гетерозис в F1 Таким образом, существование эпигенетической вариации ДНК способно объяснить отсутствие линейной связи между уровнем структурной ДНК-дивергенции и F1 гетерозисом, так же как и проявление гетерозиса при гибридизации генетически сходного материала.

Managing F1 heterosis is one of the major objectives in hybrid crop breeding programs. The classical theory considers the heterozygosity in F1 hybrids to be the main factor contributing to heterosis and therefore presumes a linear relationship between the value of genetic polymorphisms in parental lines and the heterotic response of their F1 offspring. Therefore, the genetic diversity information is viewed as a tool for selection of promising cross-combinations, but results published by different researchers are inconsistent. In this work, we studied the contributions of structural and nonstructural DNA polymorphisms to F1 heterosis manifestation. We used SSR and methyl-sensitive AFLP (MSAP with HpaII and MspI izoshisomers) protocols for obtaining specific patterns for heterotic and nonheterotic F1 hybrids of sweet pepper (Capsicum annuum L.) from a Belarusian breeding program. We found out that a certain portion of heterosis for yield-related traits might be explained by the polymorphism revealed by SSR analysis. According to our data, the total number of polymorphic SSR loci and the ratio of polymorphic and nonpolymorphic loci demonstrate a significant predictive value and can serve as additional prognostic criteria for the selection of promising cross-combinations. From the MSAP assay, we found a relationship between heterosis and the numbers of methylated and nonmethylated DNA loci for yield traits. Our results indicate that cross-hybridization may favor epiallelic modifications in F1 hybrids, presumably responsible for heterosis. Thus, epigenetic DNA variation may explain the absence of a linear relationship between the level of structural DNA divergence and F1 heterosis, as well as the manifestation of heterosis in crosses of related (genetically similar) accessions.

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The authors declare that there are no conflicts of interest present.