Strategies, Advances, and Challenges in Breeding Perennial Grain Crops

Timothy Crews,Douglas Cattani

doi:10.3390/su10072192

Abstract

The development of new perennial crop species is gaining momentum as a promising approach to change the fundamental nature of ecosystem processes in agriculture. The ecological argument for perennial crops grown in polycultures is strong, but until recently, perennial herbaceous grain crops have been absent from agricultural landscape. This is not because perennial herbaceous species do not exist in nature—there are thousands of perennial grasses, legumes, and other broad leaf plants. Rather, for a variety of reasons, early farmers focused on cultivating and domesticating annuals, and the perennial herbs were largely ignored. Today, we have a tremendous opportunity to explore another agricultural path. Building on contemporary knowledge of plant biology and genetics that early farmers lacked, and using a rapidly expanding toolbox that includes sophisticated genomic and analytical approaches, we can develop viable perennial grain crops. These crops can then be used to assemble diverse agroecosystems that regenerate soils and capture other important ecosystem functions.

Highlights

Numerous papers have been published over the last decade describing predicted improvements in soil carbon balance, nutrient retention, soil water uptake efficiency, soil microbiome functions, and weed suppression, as annual crops that require soil disturbance and/or frequent exposure to maintain are replaced by perennial crops that require minimal soil disturbance or periods of exposure [1,2,3,4,5,6,7]
Every new crop species is unique in where it is situated in the breeding pipeline, the nature of genetic challenges it faces, the traits that require breeding attention, and the progress made in breeding improvements to date
This Special Issue of Sustainability is dedicated to providing up-to-date reports on many works in progress, what lessons have been learned, and how strategies to breed perennial grain crops have been reinforced or modified based on experience using conventional breeding methods as well as new molecular or cytogenetic tools

Summary

Introduction

Numerous papers have been published over the last decade describing predicted improvements in soil carbon balance, nutrient retention, soil water uptake efficiency, soil microbiome functions, and weed suppression, as annual crops that require soil disturbance and/or frequent exposure to maintain are replaced by perennial crops that require minimal soil disturbance or periods of exposure [1,2,3,4,5,6,7]. Few papers, have been published that provide current overviews of progress in breeding specific perennial crops. Every new crop species is unique in where it is situated in the breeding pipeline, the nature of genetic challenges it faces, the traits that require breeding attention, and the progress made in breeding improvements to date. This Special Issue of Sustainability is dedicated to providing up-to-date reports on many works in progress, what lessons have been learned, and how strategies to breed perennial grain crops have been reinforced or modified based on experience using conventional breeding methods as well as new molecular or cytogenetic tools

Background

Breeding Perennial Grains

Expanding Global Effort