Has Selection for Grain Yield Altered Intermediate Wheatgrass?

Douglas Cattani,Sean Asselin

doi:10.3390/su10030688

Abstract

Perennial grains are demonstrating a greater probability of occupying land currently dedicated to other agricultural production. Arable land that is currently in use for forage or annual crop production becomes utilized. Breeding materials for the introduction of perennial grains directly into the human food chain has required utilizing existing plant materials in the domestication of species or manufacturing diverse crosses to introduce perenniality into existing crops. In the domestication of intermediate wheatgrass (Thinopyrum intermedium (Host), Barkworth and Dewey), existing forage cultivars or plant accessions were used to develop populations selected for grain production. A comparison of Cycle 3 materials from The Land Institute (TLI), Salina, KS, USA to USDA-Germplasm Resources Information Network (GRIN) accessions took place under space-planted field conditions at Carman, MB, Canada from 2011 to 2014. One hundred plants (75 TLI and 25 GRIN identified in May 2012) were followed through three seed harvests cycles with phenological, morphological and agronomic traits measured throughout. Selection for seed productivity (TLI materials) reduced the importance of biomass plant−1 on seed yield plant−1, leading to an increase in harvest index. Principal component analysis demonstrated the separation of the germplasm sources and the differential impact of years on the performance of all accessions. Path coefficient analysis also indicated that plant biomass production was of less importance on seed yield plant−1 in the TLI materials. Analysis removing area plant−1 as a factor increased both the importance of biomass and heads on seed yield cm−2 in the TLI materials, especially in the first two seed production years. Plant differences due to selection appear to have reduced overall plant area and increased harvest index in the TLI materials, indicating progress for grain yield under selection. However, a greater understanding of the dynamics within a seed production field is needed to provide insight into the development of more effective selection criteria for long-term field level production.

Highlights

Perennial grains have received greater attention in the past decade due in part to their potential to be productive over a number of years [1] and potential positive impacts on soils [2]
A few of the USDA-Germplasm Resources Information Network (GRIN) accessions lines contained highly rhizomatous plant types and these lines were uniform for this growth type
Potential for seed productivity has been selected for within the The Land Institute (TLI) materials when compared to the USDA-GRIN accessions under Manitoba growing conditions

Summary

Introduction

Perennial grains have received greater attention in the past decade due in part to their potential to be productive over a number of years [1] and potential positive impacts on soils [2]. Potential environmental benefits of perennialized cropping systems include higher carbon storage [3,4], greater water use efficiency [5], better nutrient management and greater soil protection than annual crops [6]. Environmental services would still be accrued under this increase in forage production when compared to annual crop production [8,9]. Perennial grains can retain the benefits attributed to forage production and lessen the impact due to animals in growing perennials, even if used as a dual crop [10]

Methods

Results

Discussion

Conclusion