Wheat (Triticum aestivum L.) is a critical staple crop facing severe yield losses due to increasing climate change, particularly in the rain-fed agro-ecosystems of Pakistan. The overreliance on chemical fertilizers to compensate for these losses poses serious environmental and economic challenges, highlighting the urgent need for sustainable, eco-friendly alternatives. Plant growth-promoting rhizobacteria (PGPR) and silicon nanoparticles (SiNPs) have individually shown promise in enhancing crop resilience; however, their combined field-level efficacy under rain-fed conditions remains largely unexplored. This study aimed to evaluate the synergistic effect of Bacillus cereus and different concentrations of silicon nanoparticles (SiNPs) on wheat growth and stress tolerance under rain-fed conditions. A two-year field experiment was conducted in the rain-fed zone of Pakistan (33.18°N, 73.11°E) using a randomized complete block design with eight treatments. Wheat was grown using an isolated PGPR strain (Bacillus cereus) obtained from the arid soil of Dera Ismail Khan, KP. Silicon nanoparticles were synthesized through a physical method and confirmed using SEM, EDX, and UV-Visible analysis. The study evaluated germination, morphological, physiological, mineral nutrient, biochemical, antioxidant, and yield parameters. Data represent mean values of both years. The combined application of treatment T7 (Bacillus cereus with 150 mg SiNPs) showed the highest improvement across all measured parameters. This treatment enhanced germination and significantly increased plant growth, physiology, antioxidants, and yield. Antioxidant activities increased by 16.60% (POD), 27.77% (SOD), 36.14% (CAT), and 23.63% (phosphomolybdenum). Grain yield improved by 42.56%, and harvest index increased by about 12.32% compared to the control. The synergistic use of Bacillus cereus and SiNPs performed better than using them separately. This combination, supported soil health, increased crop yield, and offered an environmentally friendly approach for wheat production in rain-fed areas of Pakistan.
Umer et al. (Wed,) studied this question.