芽孢杆菌属,尤其是在根瘤菌中,以其促进植物生长的能力和减轻几种胁迫条件的有效性而闻名。本研究旨在利用本地蜡样芽孢杆菌PM38降解毒死蜱(CP)等4种有机磷农药(OPs),profenofos(PF),久效磷(MCP),和乐果(DMT),以减轻这些农药对棉花作物生长的不利影响。菌株PM38表现出与其他芽孢杆菌属物种不同的独特特性。这些包括胞外酶的产生,氰化氢,胞外多糖,吲哚-3-乙酸(166.8μg/mL),铁载体(47.3μg/mL),1-氨基环丙烷-1-羧酸脱氨酶活性(32.4μg/mL),和磷溶解(162.9μg/mL),所有在较高浓度下观察到。该菌株还显示出对盐度(1200mM)的耐受性,干旱(20%PEG-6000),以及铜和镉(1200mg/L)。多应激反应基因的扩增,比如acds,ituC,czcD,nifH,SFP,和pqqE,进一步证实了菌株PM38对植物生长的调控和对非生物胁迫的耐受能力。在高效液相色谱(HPLC)分析之后,结果显示与第一个动力学模型具有惊人的兼容性。菌株PM38能有效降解CP(98.4%),PF(99.7%),MCP(100%),和浓度为300ppm的DMT(95.5%),在最佳pH条件下在35°C下在48小时内,显示高的测定系数(R2)分别为0.974、0.967、0.992和0.972。傅里叶变换红外光谱(FTIR)分析,mpd,菌株PM38中的opdA基因进一步支持降解OPs的潜力。此外,在胁迫条件下,用PM38接种棉花幼苗可以改善根长。菌株PM38的接种通过最小化脯氨酸来降低应力,硫代巴比妥酸反应性化合物,和电解质泄漏。菌株PM38有可能成为能够改善全球粮食安全和管理受污染地点的生物害虫防治剂的良好的多重胁迫耐受性选择。
Bacillus genera, especially among rhizobacteria, are known for their ability to promote plant growth and their effectiveness in alleviating several stress conditions. This study aimed to utilize indigenous Bacillus cereus PM38 to degrade four organophosphate pesticides (OPs) such as chlorpyrifos (CP), profenofos (PF),
monocrotophos (MCP), and dimethoate (DMT) to mitigate the adverse effects of these pesticides on cotton crop growth. Strain PM38 exhibited distinct characteristics that set it apart from other Bacillus species. These include the production of extracellular enzymes, hydrogen cyanide, exopolysaccharides, Indol-3-acetic acid (166.8 μg/mL), siderophores (47.3 μg/mL), 1-aminocyclopropane-1-carboxylate deaminase activity (32.4 μg/mL), and phosphorus solubilization (162.9 μg/mL), all observed at higher concentrations. This strain has also shown tolerance to salinity (1200 mM), drought (20% PEG-6000), and copper and cadmium (1200 mg/L). The amplification of multi-stress-responsive genes, such as acdS, ituC, czcD, nifH, sfp, and pqqE, further confirmed the plant growth regulation and abiotic stress tolerance capability in strain PM38. Following the high-performance liquid chromatography (HPLC) analysis, the results showed striking compatibility with the first kinetic model. Strain PM38 efficiently degraded CP (98.4%), PF (99.7%), MCP (100%), and DMT (95.5%) at a concentration of 300 ppm over 48 h at 35 °C under optimum pH conditions, showing high coefficients of determination (R2) of 0.974, 0.967, 0.992, and 0.972, respectively. The Fourier transform infrared spectroscopy (FTIR) analysis and the presence of opd, mpd, and opdA genes in the strain PM38 further supported the potential to degrade OPs. In addition, inoculating cotton seedlings with PM38 improved root length under stressful conditions. Inoculation of strain PM38 reduces stress by minimizing proline, thiobarbituric acid-reactive compounds, and electrolyte leakage. The strain PM38 has the potential to be a good multi-stress-tolerant option for a biological pest control agent capable of improving global food security and managing contaminated sites.