KIRTI YADAV, AWTAR SINGH, NEERAJ K. AGGARWAL* AND GAJENDER YADAV
Department of Microbiology, Kurukshetra University, Kurukshetra-136 119 (Haryana), India
*(e-mail: nkumar@kuk.ac.in; Mobile: 94169 75023)
(Received: December 20, 2023; Accepted: February 2, 2024)
ABSTRACT
Soil microbes are the vibrant components of rhizospheric microbiome and control vital biogeochemical processes. This investigation assessed the effect of long-term irrigation with water containing high residual sodium carbonate (RSC) and crop cultivars on microbial populations and wheat yields. Five types of irrigation water having different levels of residual sodium carbonate comprised: T1–Best available groundwater, T2–Residual sodium carbonate water 1 (RSC- 5 me/L), T3–RSC water 2 (RSC 10 me/L), T4– RSC water 3 [RSC 10 treated with gypsum (RSC 10 neutralized to RSC 5 me/L with gypsum) and T5–RSC water 4 [RSC 10 treated with sulphur (RSC 10 neutralized to RSC 5 me/L with sulphur) continuously applied under lysimeters. RSC water significantly deteriorated soil microbial population under both wheat cultivars. The maximum reduction was noticed under RSC 10 water irrigation. Soil microbial population negatively associated with soil exchangeable percentage (R2 = 0.467-0.743) and sodium adsorption ratio of soils (R2= 0.485-0.831) after harvest of both the crop cultivars. Moreover, wheat yield was also significantly reduced with continuous irrigation having high level of RSC in water. Decline was more in HD 3226 compared to KRL 210 cultivars. Partial neutralization of RSC from 10 to 5 me/L through gypsum and sulphur recovered the soil microbial population and wheat yield. However, it was not reasonable to sustain the soil microbial population and wheat yield under long term. Amelioration of RSC through different amendments below RSC 5 me/L further requires research to obtain acceptable soil microbial population and yield.
Key words: Wheat varieties, soil microbial populations, residual sodium carbonate, irrigation