ABSTRACT Micro-RNA268 (miR268) plays an important role in modulating plant responses to different types of biotic and abiotic stresses. Zinc (Zn) has an essential physiological role in plants and is often deficient in crops. A study was conducted under controlled lowland (flooded) rice cultivation conditions to investigate the potential role of miR268 overexpression in modulating rice seedling resilience and yield in response to foliar Zn application. The rice seedlings were exposed to different Zn supplementation treatments: control (without zinc application), root dipping of seedlings in 0.5% zinc solution, basal application (30 kg ha−1), and foliar applications of Zn (0.5%) at 30, 45, 60, 75, and 90 days of transplantation. Different parameters such as growth characteristics, chlorophyll content, and yield metrics were systematically evaluated post-harvest. The study demonstrated that miR268 overexpression enhanced Zn uptake, with foliar Zn application (90 days) yielding the highest chlorophyll content (1.85%) and lowest oxidative stress (malondialdehyde, MDA: 1.25 nmol g−1 fresh weight, FW). Basal Zn application resulted in maximal Zn accumulation (roots: 29.6 µg g−1 dry weight, DW; shoots: 37.5 µg g−1 DW) and a 15.5% increase in 1000-kernel weight. These findings confirm miR268‘s central role in Zn homeostasis: foliar Zn at 90 days was most effective for enhancing photosynthesis and reducing oxidative stress, whereas basal application was superior for maximizing Zn accumulation and grains weight. Therefore, the optimal method depends on the target outcome, foliar application for stress protection or basal application for yield improvement-thus providing flexible management for Zn-deficient soils.
Sobia Shafqat, S. Qaisrani, M. Amjad et al.· Communications in Soil Scien...· 0 citations
Partial replacement of chemical fertilizers, particularly nitrogen fertilizers, with biological fertilizers is considered an effective strategy for reducing the negative environmental impacts associated with excessive fertilizer use. This study aimed to optimize N use through the application of bacterial-based biofertilizer, specifically plant growth-promoting rhizobacteria (PGPR), in different maize cultivars under semi-arid conditions. A randomized complete block design (RCBD) arranged in a split-plot arrangement was used, with the three hybrids (Shahkar, Bumbus and DK 7024) assigned to the main plots and different N treatments allocated to sub-plots. The field experiment was conducted during two consecutive spring seasons (Feb to June 2024 and 2025). The N treatments were defined as follows: control, 100% recommended N (200 kg/ha), 100% N with Pseudomonas stutzeri, 100% N with Bacillus subtilis, 100% N with Enterobacter sp., 50% N with Pseudomonas stutzeri, 50% N with Bacillus subtilis, 50% N with Enterobacter sp., 100% Pseudomonas stutzeri, 100% Bacillus subtilis, and 100% Enterobacter sp. The N treatments included synthetic fertilizer alone at the 100% recommended N rate and a combination of 100%, 50% and 0% of recommended levels with three N-fixing bacterial strains. Among the hybrids, DK 7024 exhibited the highest 1000-grain weight (349 g and 362.5 g), grain yield (6756 and 6971 kg ha−1) and total dry matter (17,500 and 18,368 kg ha−1) in 2024 and 2025, respectively. Among N levels, maximum 1000-grain weight, grain yield and total dry matter were noticed in 100% N with Enterobacter sp.: 402 g, 8446 kg ha−1 and 21,656 kg ha−1 in 2024 and 421 g, 8684 kg ha−1 and 22,237 kg ha−1 in 2025. Nitrogen application increased grain yield and total dry matter production; however, the treatment combined with 100% recommended synthetic N fertilizer with biofertilizer (Enterobacter sp.) showed superior performance compared with 100% N applied through only the synthetic fertilizer. The interaction between maize hybrids and N levels was statistically non-significant, suggesting that 100% N plus biofertilizers could be an effective strategy for achieving higher yields across different maize cultivars. Additionally, the beneficial effects of PGPR may contribute to sustainable agricultural practices. Further research is recommended to evaluate strategies involving reduced-N inputs combined with biological fertilizer, including the application of 100% N with biofertilizer. The present study suggests that N application in combination with biofertilizers has the potential to improve crop growth while promoting sustainable crop production.
Sajjad Hussain, S. Qaisrani, Muhammad Mubeen et al.· Nitrogen· 0 citations