Устойчивость картофеля к вирусам: современное состояние и перспективы

Одна из важнейших продовольственных культур в мире, картофель (Solanum tuberosum) заражается многими вирусами, девять из которых имеют важное экономическое значение, вызывая существенные потери урожая и заметное снижение качества продукции. Для минимизации последствий вирусных инфекций в странах с высоким уровнем развития сельского хозяйства поддерживаются и совершенствуются санитарные меры, предусматривающие постоянный мониторинг распространения вирусов и сертификацию посадочного материала на основе диагностики и оздоровления сортов картофеля. Однако в долгосрочной перспективе предпочтительным является создание устойчивых к вирусам сортов картофеля. Методами традиционной селекции и генно-инженерными методами с использованием генов природной устойчивости, источником которых, как правило, служат дикорастущие виды Solanum, или с помощью вирус-специфических последовательностей к настоящему времени получен ряд сортов/линий картофеля, устойчивых к большинству вирусов. Однако названные подходы имеют существенные ограничения, обусловленные, в частности, тем, что приобретаемая устойчивость специфична (против отдельных вирусов), недолговременна и способна преодолеваться вирусом, а также наличием регуляторных запретов на использование генно-модифицированных растений. На современном этапе новые технологии редактирования генома с целью дизайна генов открывают широкие возможности для создания новой генерации генов устойчивости. Наиболее перспективными представляются: направленный мутагенез генов специфической устойчивости для придания им более широкого спектра действия; использование генов неспецифической или «нехозяйской» устойчивости (non-host resistance), что позволяет получать растения, устойчивые к неродственным вирусам, а в некоторых случаях и к другим патогенам и даже абиотическим стрессам. Идентификация генов, вовлеченных в механизмы «нехозяйской» устойчивости, только начинается. Новым источником неизвестных до настоящего времени факторов, вовлеченных в разнообразные сигнальные пути защитного ответа растения на вирусную инфекцию, является клеточное ядро. Описанию подходов и проблем, связанных с получением устойчивых к вирусным инфекциям растений картофеля, посвящен настоящий обзор.

картофель, вирусы картофеля, гены устойчивости, защитный ответ, факторы клеточного ядра

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