Exogenous Application of Plant Growth Regulators Improves Economic Returns, Grain Yield and Quality Attributes of Late-Sown Wheat under Saline Conditions

Abstract

Studies on the wheat response under late sowing (LS) and salinity stress (SS) are available, however, in rice-wheat and cotton-wheat cropping systems, wheat planting is often delayed resulting in co-occurrence of LS and SS in salt affected soils. This two-year field study was conducted to evaluate the influence of foliar application of plant growth regulators (PGRs) [thiourea (TU), salicylic acid (SA) and hydrogen peroxide (H₂O₂); water and no application were taken as control] on the productivity, grain quality and economic returns of timely-sown (TS) and LS wheat under normal (NC) and natural saline conditions (SS; EC 11.27 dS m^− 1). Delay in sowing and planting in naturally saline soils caused a significant decrease in plant growth, grain yield, grain quality and net economic returns during both years of study. Late planting and SS caused a significant reduction in grain yield reduction by 40.58% and 34.72% (LS) and 40.66% and 42.89% (SS) compared with respective controls during 2021 and 2022, respectively. However, the influence of co-occurrence of LS and SS was more devastating than the individual stress causing 62.17% and 60.18% reduction in grain yield than the respective control during 2021 and 2022, respectively. However, the application of all PGRs improved the grain yield, grain quality and economic turnover under SS and LS stress. The order of improvement in grain yield by the application of PGRs treatments was TU > SA > H₂O₂. In conclusion, the application of different plant growth regulators improved economic returns, grain yield and quality attributes of late-sown wheat under saline conditions. In this regard, TU application was the most effective.