Overcoming the trade‐off between grain weight and number in wheat by the ectopic expression of expansin in developing seeds leads to increased yield potential

Calderini, Daniel F., Castillo, Francisca M., Arenas M, Anita., Molero, Gemma., Reynolds, Matthew P., Craze, Melanie., Bowden, Sarah., Milner, Matthew J., Wallington, Emma J., Dowle, Adam., Gomez, Leonardo D., McQueenMason, Simon J.

Keywords: transgenic, pericarp, grasses, grain weight, grain number, Expansin protein

Abstract

Wheat is the most widely grown crop globally, providing 20% of all human calories and protein. Achieving step changes in genetic yield potential is crucial to ensure food security, but efforts are thwarted by an apparent trade‐off between grain size and number. Expansins are proteins that play important roles in plant growth by enhancing stress relaxation in the cell wall, which constrains cell expansion. Here, we describe how targeted overexpression of an α‐expansin in early developing wheat seeds leads to a significant increase in grain size without a negative effect on grain number, resulting in a yield boost under field conditions. The best‐performing transgenic line yielded 12.3% higher average grain weight than the control, and this translated to an increase in grain yield of 11.3% in field experiments using an agronomically appropriate plant density. This targeted transgenic approach provides an opportunity to overcome a common bottleneck to yield improvement across many crops.

Más información

Título de la Revista: NEW PHYTOLOGIST
Volumen: 230
Número: 2
Editorial: Wiley
Fecha de publicación: 2020
Página de inicio: 629
Página final: 640
Idioma: inglés
URL: https://nph.onlinelibrary.wiley.com/doi/10.1111/nph.17048