Emergence, height, and yield of tall, NewHy, and green wheatgrass forage crops grown in saline root zones

Abstract

. 2005. Emergence, height, and yield of tall, NewHy, and green wheatgrass forage crops grown in saline root zones. Can. J. Plant Sci. 85: 863-875. The salinity tolerance of a crop relates to its inherent ability to yield economic product while subjected to root-zone salinity. Tall wheatgrass [Thinopyrum ponticum (Podp.) Liu & Wang, previously Agropyron elongatum (Horst.) Beauv.] ranks as one of the most salt-tolerant forage crops, but producers feeding or grazing livestock with it often report of its poor palatability. NewHy [Elytrigia repens (L.) Nevski × Pseudoroegneria spicata (Pursh.) A. Love] and green wheatgrasses (Elymus hoffmannii Jensen and Asay) are new forages with potentially better palatability. In order to determine the responses of these forages to saline rooting media, two tests were conducted in Canada's Salinity Tolerance Testing Facility. The plants were grown in sand tanks flushed four times daily with hydroponic solutions consisting of nutrients and salts dominated either by chloride ions measuring from 1.5 to 48 dS m -1 or by sulphate ions from 1.5 to 50 dS m -1 . In the chloride test, maximum emergence-survival, emergence rate, and emergence at the time of maximum rate for Orbit tall wheatgrass differed significantly from green wheatgrass (Breeding Strain A6) and NewHy. The maximum percent emergence and survival within the range of test salinity levels averaged 93, 88, 86% for tall, NewHy, and Strain A6 wheatgrasses, respectively. In the sulphate test, maximum percent emergence-survival averaged 94, 91, and 87% for Orbit tall wheatgrass and green wheatgrass breeding strains A6 and S2 across the eight salinity levels of the test. Relative crop heights at harvest did not differ significantly among the test forages in either test. In the chloride test, shoot biomass yields relative to the salt-free production analysed by the modified-discount equation resulted in salinity-tolerance-indices of 11.2, 5.7, and 12.9 for tall, NewHy, and green wheatgrasses, respectively. In the sulphate test, salinity-tolerance indices for the tall wheatgrass, A6 and S2 green wheatgrass strains registered 11.7, 12.8, and 12.5, respectively. This and the covariance yield analyses based on paired t-tests lead to the inference that the salinity tolerance for both strains of green wheatgrass equalled that of the Orbit tall wheatgrass and exceeded that of the NewHy. Producers will soon have the option of growing AC Saltlander, a variety of green wheatgrass (Strain S2), which has just been released for commercialization and seed increase. For personal use only.

Flooding and salinity reduces AC saltlander green wheatgrass and smooth bromegrass productivity

“…As expected, ACS forage yields and plant heights were higher than SB under saline stress (Figures 7 and 9), which indicates that ACS salinity tolerance was better than that of SB, since ACS was developed to tolerate soil salinity (Steppuhn & Asay, 2005; Steppuhn et al., 2006).…”

“…AC Saltlander green wheatgrass ( Elymus hoffmannii Jensen & Asay, ACS) was developed at Agriculture and Agri‐Food Canada ‐Swift Current Research and Development Centre (AAFC‐SCRDC) to tolerate up to severe root‐zone salinity (EC e < 16 dS m −1 ) and have good forage performance (Steppuhn & Asay, 2005; Steppuhn, Jefferson, Iwaasa, & McLeod, 2006). It was registered in 2006, and has been commercially available in Canada since 2008.…”

AC Saltlander green wheatgrass

“…AC Saltlander has been specifically selected for salt tolerance and compares very favourably with the tolerance of tall wheatgrass. The above-ground biomass production of AC Saltlander, while growing in progressively greater root-zone salinity, tended to perform as good or better than Orbit tall wheatgrass up to an equivalent electrical conductivity of saturated soil paste extract (EC e ) of 12 dS m -1 (Steppuhn and Asay 2005). On a relative-yield basis, the green wheatgrass AC Saltlander statistically equalled the EC e -productivity exhibited by Orbit tall wheatgrass at all salinity levels (Fig.…”

“…1). A covariance analysis of the relative shoot biomass produced by the two wheatgrasses grown across the full range of root-zone salinity (from very slight to very severe) failed to show any significant differences between them (Steppuhn and Asay 2005). Salinity tolerance indices equalled 11.73 and 12.51 for Orbit and AC Saltlander, respectively.…”

Proteomic Analysis of Seedling Roots of Two Maize Inbred Lines That Differ Significantly in the Salt Stress Response

“…Under salt stress conditions, the establishment of healthy seedlings is extremely important for maize plant subsequent development. Roots are the primary sites of salinity perception, and salt sensitivity in roots limits the productivity of the entire plant [ 5 ]. Therefore, obtaining a better understanding of salt-responsive mechanisms in seedling roots is critical for improving plant salt tolerance.…”