Asexual reproduction through clonal seeds: mechanisms to application

Introduction

Some plant species have abandoned sex and produce clonal seeds by apomixis; here, we will explore how this occurs and exploit these insights to develop novel breeding technologies.

Background

In contrast to most eukaryotic species in which reproduction is sexual, a minority of plants and animals have evolved alternative – asexual – reproductive strategies. In plants, apomixis allows clonal transmission of favorable, hybrid genotypes through seeds over unlimited generations.

Hybrid crop varieties are stress-resistant and high-yielding due to hybrid vigor, yet they reproduce sexually. The introduction of apomixis in hybrid crops would allow stable inheritance of hybrid vigor through seeds, in perpetuity, and eradicate the need to continuously re-make hybrids by crossing. However, our knowledge of the genetic and molecular basis of apomixis remains incomplete, and blueprints for synthetic apomixis in crops must be established.

Project Goals

This project will decipher the function and evolution of a novel PARTHENOGENESIS gene that I recently demonstrated causes asexual embryo formation in naturally apomictic dandelions. Harnessing and extending fundamental findings, synthetic apomixis systems will be developed in two important vegetable crops – hybrid lettuce and tomato – allowing the full complement of hybrid traits to be faithfully inherited through seeds. Ultimately, apomixis in crops could revolutionize the €22 billion hybrid seed industry, make hybrid seeds readily available for all, and facilitate sustainable, high-performance agriculture around the world.

Specific Objectives

Specifically, this project will involve:

1. Deciphering how a PARTHENOGENESIS gene homologue functions during sexual reproduction.
2. Optimizing the expression of PARTHENOGENESIS factors through evolutionary insights and mutagenesis.
3. Engineering synthetic apomixis – a holy grail of plant breeding – in two important dicot crop species by skipping meiosis and triggering PARTHENOGENESIS.