Convergent Evolution of the Seed Shattering Trait.

Valerio Di Vittori,Giovanna Attene,Roberto Papa,Domenico Rau,Elena Bitocchi,Laura Nanni,Monica Rodriguez,Elisa Bellucci,Tania Gioia

doi:10.3390/genes10010068

Valerio Di Vittori, Giovanna Attene + Show 7 more

Open Access

https://doi.org/10.3390/genes10010068

Copy DOI

Abstract

Loss of seed shattering is a key trait in crop domestication, particularly for grain crops. For wild plants, seed shattering is a crucial mechanism to achieve greater fitness, although in the agricultural context, this mechanism reduces harvesting efficiency, especially under dry conditions. Loss of seed shattering was acquired independently in different monocotyledon and dicotyledon crop species by ‘convergent phenotypic evolution’, leading to similar low dehiscent and indehiscent phenotypes. Here, the main aim is to review the current knowledge about seed shattering in crops, in order to highlight the tissue modifications that underlie the convergent phenotypic evolution of reduced shattering in different types of fruit, from the silique of Brassicaceae species, to the pods of legumes and spikes of cereals. Emphasis is given to legumes, with consideration of recent data obtained for the common bean. The current review also discusses to what extent convergent phenotypes arose from parallel changes at the histological and/or molecular levels. For this reason, an overview is included of the main findings relating to the genetic control of seed shattering in the model species Arabidopsis thaliana and in other important crops.

Highlights

Domestication of wild species represents a crucial step for human civilization, in that hunter/gatherer humans became farmers
This review focuses on the issue of convergent evolution, with an illustration of recent findings on the phenotypic evolution of seed shattering at the histological level
We aim to provide knowledge about the genetic control of seed shattering in the model species A. thaliana, along with the main shattering-related genes that have been identified in important crops

Summary

Introduction

Domestication of wild species represents a crucial step for human civilization, in that hunter/gatherer humans became farmers. One of the most intriguing aspects of studying seed shattering is to determine whether convergent phenotypic evolution was the consequence of parallel adaptive trajectories with mutation and selection at homologous loci, and whether the genetic pathway underlying seed shattering is conserved across species. It is worth investigating whether macroscopic convergent phenotypic changes are determined by similar phenotypic modifications at the histological level between closest related species. We aim to provide knowledge about the genetic control of seed shattering in the model species A. thaliana, along with the main shattering-related genes that have been identified in important crops

Histological Modifications That Underlie Seed Shattering in Crops

Representative

Illustration

Findings

Conclusions