Suppression of canary grass (Phalaris minor) with simultaneous use of rhizobacteria and sunflower allelopathy

Abstract

Although the environmental and health challenges associated with conventional herbicide use are well-documented, studies comparing the potential of microbial and plant allelopathy for weed management remain limited. This study aims to fill this gap by evaluating the combined and individual impacts of Pseudomonas fulva T19 and sunflower extract on suppressing the weed canary grass (Phalaris minor Retz.) in wheat, offering a potential eco-friendly alternative to chemical herbicides. The experiment includes 10 treatments: 1) control, 2) sunflower soil incorporation 1% (1% SSI), 3) sunflower extract 2.5% (2.5% SE), 4) sunflower extract 5% (5% SE), 5) sunflower extract 10% (10% SE), 6) T19 bacterial strain (AB), 7) 1% SSI + AB, 8) 2.5% SE + AB, 9) 5% SE + AB, and 10) 10% SE + AB. Applying AB and SE significantly (p ≤ 0.05) suppressed the P. minor and promoted wheat's biochemical properties, growth, and yield. Specifically, AB + 10% SE notably promoted wheat root and shoot lengths (46.6 and18.1%) and their biomasses (38.5 and 30.1%) as compared to the control. Moreover the similar treatment also promoted chlorophyll ‘a’ and ‘b’ contents (32.8 and 28.7%), antioxidant enzymes (APX by 40.4%, CAT by 45.6% and POD by 40.2%), and grain yield per pot by 21.7% by causing the reduction in such characteristics of P. minor. Principal component analysis revealed a negative correlation between wheat and P. minor attributes under the influence of AB and SE allelopathy. Pearson correlation indicated positive correlations among wheat attributes and negative ones with P. minor. Ultimately, combining AB with SE synergistically enhanced wheat growth and yield by suppressing P. minor, suggesting a sustainable alternative to herbicides.