Uncovering useful variability for agronomics and disease resistance...

Citation

Humphreys G, Cao W, Kalikililo A, Langille L, Henriquez MA, Blackwell B, Fedak G, Cloutier S (2019) Uncovering useful variability for agronomics and disease resistance within a diverse wheat collection. Proc 1st International Wheat Congress, Saskatoon, July 21-27, P 447 (poster)

Plain language summary

By 2050, it is estimated that global food needs will increase at least 30% due to an ever growing world population. Wheat provides 20% of the world’s caloric needs so a significant increase in wheat production is necessary. There is concern that we do not have enough genetic variability to improve wheat to meet future food needs. A diverse 210 entry collection was generated that had 51% Triticum aestivum L. (2n=6X) including 6 subspecies and 20 synthetic wheat lines as well as 49% Triticum turgidum L. (2n=4x) including 7 subspecies. Variability for grain yield, heading date, plant height, straw strength, maturity and seed mass were observed as well as disease resistance to Fusarium head blight. The variability observed may be useful to improve these characteristics in wheat breeding programs.

Abstract

By 2050, it is estimated that global food needs will increase at least 30% due to an ever growing world population. Wheat provides 20% of the world’s caloric needs so a significant increase in wheat production is necessary. Since significant additions to arable land are unlikely, higher wheat production must generated through increased grain yield/hectare. There is a considerable anxiety that variability for agronomic traits and disease resistance in adapted wheat is insufficient to meet these yield targets. To address this concern, a 210 entry wheat diversity panel was generated composed of 51% Triticum aestivum L. (2n=6X) including 6 subspecies and 20 synthetic wheats as well as 49% Triticum turgidum L. (2n=4x) including 7 subspecies. The panel was field evaluated for agronomic traits at Ottawa, Canada in 2017 using a lattice design with 2 replicates. Fusarium head blight (FHB) resistance testing was conducted in inoculated nurseries at Ottawa, ON and Morden, MB. Significant variability for grain yield, heading date, plant height, straw strength, maturity and seed mass were observed. Among 10% of entries with the highest grain yield were accessions of T. aestivum ssp. spelta (2), T. aestivum ssp. compactum (1), T. turgidum ssp. diccocum (2), T. turgidum ssp. dicoccoides (1). The remaining entries were hexaploid (13) and durum (1) wheat varieties. Lowest 10% of entries for grain yield was composed of T. aestivum synthetics, T. aestivum ssp. sphaerococcum, T. turgidum ssp. dicoccum and ssp. diccocoides accessions. Among the highest yielding group, T. spelta and T. dicoccoides accessions were significantly (P<0.05) later for heading and maturity compared to the wheat varieties. High yielding T. spelta accessions were significantly (P<0.05) taller than the tallest wheat variety. Seed mass of the high yielding T. spelta and T. dicoccoides accessions were significantly higher than the overall mean seed mass, and similar to the highest yielding wheat varieties. Leaf spot ratings for the high yielding T. spelta and T. dicoccoides accessions were significantly (P<0.05) lower than all but two of the high yielding varieties. FHB index scores within the panel ranged from 0.5 to 100 and deoxynivalenol content (DON) ranged from 0.2 to 158.1 ppm. Fusarium index scores and DON of the high yielding T. spelta accessions rated among the 8 most resistant lines for both FHB index and DON. Screening of the wheat diversity panel has identified promising accessions for future breeding work.