Effects of Increasing Salinity by Drip Irrigation on Total Grain Weight Show High Yield Potential of Putative Salt-Tolerant Mutagenized Wheat Lines

Abstract

Twenty-three lines from a mutagenized Bangladeshi BARI Gom-25 wheat population that included previously identified salt-tolerant lines, and the BARI Gom-25 control variety, were cultivated in a drip-irrigated salinity test field at Salt Farm Texel, Netherlands, to assess their performance during salt stress in European climatic conditions. Lines were tested at irrigation salinity levels of 1, 4, 8, 12, 16, and 20 dS m−1 in four repetitions of plots with 24 plants per plot. Average plant height, tiller number, spike length, frequency of live plants, and total grain weight (TGW) were recorded as functions of seasonal mean pore water salinity in the soil. Increases in salinity triggered reductions in all evaluated variables of the assessed lines and the control variety. However, nine mutagenized lines had at least twofold higher mean TGW than the control variety, 18.73 ± 4.19 g/plot at 1–16 dS m−1 salinity levels. Common models of salt tolerance confirmed this pattern, but there were no clear differences in salinity tolerance parameter estimates between the mutagenized lines and the control variety. Thus, despite the apparent similarity in responses of all lines to salinity increase, we clearly identified lines that tended to have higher TGW at given salinities than the control variety. This higher TGW at the full range of salinity treatments indicates not only a possible higher salinity tolerance but a higher yield potential as well. The mechanisms involved clearly warrant further attention.

Improved Salinity Tolerance-Associated Variables Observed in EMS Mutagenized Wheat Lines

“…OA62 was the only line selected in this study with a 2-fold higher total grain weight than the control in a previous study (OA62 then designated the name OA120) performed at the Salt Farm Texel [ 12 ]. The difference from the observed TKW can be due to fewer plants used in our study (three versus 96), different environments (indoor versus outdoor), and that salt was applied two weeks earlier in our study [ 12 ]. OA10 had favorable ion accumulation trends but low biomass, low water use efficiency, and low yield.…”

“…This raised the question of whether the lines would differ in any defined salt tolerance parameters if they experienced elevated saline conditions later in their development. A recent study compared 23 of these wheat lines using soil salinity induced by controlled drip irrigation in moderate European outdoor climatic conditions [ 12 ]. It showed that nine lines had a 2-fold better total grain weight than the control.…”

Halotolerant Endophytic Bacteria Regulate Growth and Field Performance of Two Durum Wheat Genotypes with Contrasting Salinity Tolerance Potential

“…For instance, soil amendments such as biochar application improved wheat productivity under saline conditions [21]. Irrigation management using drip irrigation was effective in managing salinity and improving wheat performance [22]. The salt tolerance trait in different plants can be also increased by using eco-friendly approaches, including the exploitation of halotolerant microorganisms that interact with plant roots [23].…”

Root Ions Fluxes and Osmolarity Changes in Grass Species Differing in Salinity Tolerance

“…The copyright holder for this this version posted October 19, 2023. ; https://doi.org/10.1101/2023.10.16.562608 doi: bioRxiv preprint 2 uptake, leading to physiological drought, and disrupts the ionic balance within plants (Abrol et al, 1988;Hu & Schmidhalter, 2005;Sinclair, 2011;Chele et al, 2021;Singh et al, 2022;Alharbi et al, 2022). Utilizing salt-tolerant crop species and varieties is one potential solution to maintain food productivity and security (Cuartero et al, 2006;Gul et al, 2022;Mousavi et al, 2022;Egea et al, 2023).…”