Development and characterization of wheat-sea wheatgrass (Thinopyrum junceiforme) amphiploids for biotic stress resistance and abiotic stress tolerance

Authors: LI, WANLONG - South Dakota State University; ZHANG, QIJUN - North Dakota State University; WANG, SHUWEN - The Land Institute; LANGHAM, MARIE - South Dakota State University; SINGH, DILKARAN - South Dakota State University; Bowden, Robert; Xu, Steven

Submitted to: Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/5/2018
Publication Date: 10/19/2018
Citation: Li, W., Zhang, Q., Wang, S., Langham, M.A., Singh, D., Bowden, R.L., Xu, S.S. 2018. Development and characterization of wheat-sea wheatgrass (Thinopyrum junceiforme) amphiploids for biotic stress resistance and abiotic stress tolerance. Theoretical and Applied Genetics. 132:163–175. https://doi.org/10.1007/s00122-018-3205-4.
DOI: https://doi.org/10.1007/s00122-018-3205-4

Interpretive Summary: Production of wheat, the most widely cultivated crop, is facing numerous challenges from environmental and biotic stresses, which are further exacerbated by the negative impacts of climate change. Introduction of new variation into crop plants from their wild relatives is an effective approach to break the genetic bottlenecks and enhance future cultivars. Sea wheatgrass (SWG) is adapted to stressful coastal environments and is an excellent source for genetic improvement of wheat for environmental stress tolerance. In this study, we developed and characterized progeny of three crosses between SWG and emmer or durum wheat for tolerance to stresses and resistance to wheat diseases and pests. Tolerance was found for waterlogging, manganese toxicity, salinity, low nitrogen, and possibly heat as well as wheat streak mosaic virus, Fusarium head blight, and wheat stem sawflies. These new traits could be used for development of new stress-tolerant wheat cultivars.

Technical Abstract: Wheat production is facing numerous challenges from biotic and abiotic stresses. Alien gene transfer has been an effective approach for wheat germplasm enhancement. Thinopyrum junceiforme, also known as sea wheatgrass (SWG), is a distant relative of wheat and a relatively untapped source for wheat improvement. In the present study, we developed a complete amphiploid, 13G819, between emmer wheat and SWG for the first time. Analysis of the chromosome constitution of the wheat-SWG amphiploid by multiple-color genomic in situ hybridization indicated that SWG is an allotetraploid with its J1 genome closely related to Th. bessarabicum and Th. elongatum and its J2 genome was derived from an unknown source. Two SWG-derived perennial wheat lines, 14F3516 and 14F3536, are partial amphiploids and carry 13 SWG chromosomes of mixed J1 and J2 genome composition, suggesting cytological instability. We challenged the amphiploid 13G819 with various abiotic and biotic stress treatments together with its wheat parent. Compared to its wheat parent, the amphiploid showed high tolerance to waterlogging, manganese toxicity and salinity, low nitrogen and possibly to heat as well. The amphiploid 13G819 is also highly resistant to the wheat streak mosaic virus (temperature insensitive), and Fusarium head blight. All three amphiploids had solid stems, which confer resistance to wheat stem sawflies. All these traits make SWG an excellent source for improving wheat resistance to diseases and insects and tolerance to abiotic stress.