Scholarlink

<p>Heavy metal contamination threatens soil health and ecosystem stability. Endophytic bacteria from metal-tolerant plants can enhance phytoremediation. In this study, twenty-four endophytic bacterial isolates were isolated from leaves and roots of <i>Cynodon dactylon</i> collected from a metal-contaminated industrial site in Islamabad, Pakistan. All isolates were screened for plant growth-promoting (PGP) traits and heavy metal (Zn, Pb, Cu, Cr) tolerance. Quantitative assays revealed that 95.8% of isolates solubilised phosphate (maximum zone 17&#xa0;mm by CDR11), all produced indole acetic acid (IAA) (3.2–14.7&#xa0;µg/mL) and ammonia (0.8–6.5&#xa0;µg/mL). Metal tolerance tests showed minimum inhibitory concentrations (MIC) of 50–100&#xa0;µg/mL. Isolates CDL3, CDL2 and CDR1 exhibited maximum tolerance to all four metals at 100&#xa0;µg/mL. Seed germination assays with <i>Linum usitatissimum</i> demonstrated significant (<i>p</i> &lt; 0.05) increases in germination percentage (up to 91.1% by CDR6 vs. 66.6% control) and seedling vigour. 16&#xa0;S rRNA gene sequencing of six potential isolates identified them as <i>Bacillus thuringiensis</i> CDL2 (99.78%), <i>Bacillus cereus</i> CDL3 (99.90%), <i>Bacillus cereus</i> CDL5 (99.90%), <i>Bacillus</i> sp. CDL9 (98.52%), <i>Bacillus</i> sp. CDR1 (100%) and <i>Bacillus subtilis</i> CDR12 (99.90%). These results demonstrate that metal-resistant <i>Bacillus</i> endophytes from <i>C. dactylon</i> possess multiple PGP traits and significantly improve flax seed germination, highlighting their potential as bio-inoculants for phytoremediation of metal-polluted soils.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Isolation and characterization of metal resistant plant growth promoting endophytic bacteria from Cynodon dactylon L. (Pers)

  • 期刊论文

  • 发表日期：

    2026年6月2日

查看全文
  • Aatika Shehzadi,
  • Shazia Rehman,
  • Sadia Malik,
  • Jaria Sadia,
  • Hadia Kalsoom,
  • Aqsa Mubeen,
  • Ammara Javed

摘要

Heavy metal contamination threatens soil health and ecosystem stability. Endophytic bacteria from metal-tolerant plants can enhance phytoremediation. In this study, twenty-four endophytic bacterial isolates were isolated from leaves and roots of Cynodon dactylon collected from a metal-contaminated industrial site in Islamabad, Pakistan. All isolates were screened for plant growth-promoting (PGP) traits and heavy metal (Zn, Pb, Cu, Cr) tolerance. Quantitative assays revealed that 95.8% of isolates solubilised phosphate (maximum zone 17 mm by CDR11), all produced indole acetic acid (IAA) (3.2–14.7 µg/mL) and ammonia (0.8–6.5 µg/mL). Metal tolerance tests showed minimum inhibitory concentrations (MIC) of 50–100 µg/mL. Isolates CDL3, CDL2 and CDR1 exhibited maximum tolerance to all four metals at 100 µg/mL. Seed germination assays with Linum usitatissimum demonstrated significant (p < 0.05) increases in germination percentage (up to 91.1% by CDR6 vs. 66.6% control) and seedling vigour. 16 S rRNA gene sequencing of six potential isolates identified them as Bacillus thuringiensis CDL2 (99.78%), Bacillus cereus CDL3 (99.90%), Bacillus cereus CDL5 (99.90%), Bacillus sp. CDL9 (98.52%), Bacillus sp. CDR1 (100%) and Bacillus subtilis CDR12 (99.90%). These results demonstrate that metal-resistant Bacillus endophytes from C. dactylon possess multiple PGP traits and significantly improve flax seed germination, highlighting their potential as bio-inoculants for phytoremediation of metal-polluted soils.