Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India.
Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India; Hawkesbury Institute for the Environment, Western Sydney University, Hawkesbury Campus, Pobox 1797, Penrith NSW, 2750, Sydney, Australia.
Chemosphere. 2019 May;223:636-650. doi: 10.1016/j.chemosphere.2019.02.053. Epub 2019 Feb 14.
The main aim of this study is to investigate the toxicity of organophosphate (OPs) insecticides monocrotophos (MCP) and chlorpyrifos (CLS) on plant growth promoting (PGP) properties and seed germination of brinjal, tomato and okra vegetables inoculated by Microbacterium hydrocarbonoxydans (BHUJP-P1), Stenotrophomonas rhizophila (BHUJP-P2), Bacillus licheniformis (BHUJP-P3) and Bacillus cereus (BHUJP-P4). Maximum increase in microbial growth (52.6% & 47.9%) with enhanced EPS production (447.67 mg/ml & 75.00 mg/ml) was showed by BHUJP-P4 and BHUJP-P3 at 10× dose of MCP and CLS over control, BHUJP-2 and BHUJP-P1 respectively. Simultaneously, both strains recorded minimum reduction in PGP activities and seed germination at 3× dose of both insecticides as compared to BHUJP-2 and BHUJP-P1, respectively. Strains BHUJP-P3 and BHUJP-P4 showed 83 and 81% of monocrotophos degradation at 50 mg/kg concentration; 81 and 80% at 150 mg/kg concentration within 5days respectively. Concurrently, these strains BHUJP-P3 and BHUJP-P4 were recorded 53 and 90% of chlorpyrifos degradation at 50 mg/kg concentration; 49% and 87% at 100 mg/kg concentration within 72 h, respectively. The OPs insecticide degrading gene opdA and opd was found in strain BHUJP-P3 and BHUJP-P4, respectively. The multifarious biological activities of strain BHUJP-P3 and BHUJP-P4 showed maximum tolerance against insecticide, and minimum reduction in P-solubilisation, IAA, siderophore and HCN production for plant growth promotion and biological control under insecticide stress. Thus, these novel isolates may be used as biodegradation of organophosphate insecticide and plant growth promoting bacterial (PGPB) inoculum for enhancing seed germination of vegetables under stress insecticide. These novel strains will be environment friendly, socially acceptable and economically viable.
本研究的主要目的是研究有机磷（OP）杀虫剂久效磷（MCP）和毒死蜱（CLS）对促生特性和茄子、番茄和秋葵种子发芽的毒性，这些蔬菜接种了烃氧化微杆菌（BHUJP-P1）、嗜麦芽寡养单胞菌（BHUJP-P2）、地衣芽孢杆菌（BHUJP-P3）和蜡状芽孢杆菌（BHUJP-P4）。在 MCP 和 CLS 的 10×剂量下，BHUJP-P4 和 BHUJP-P3 表现出最大的微生物生长增加（52.6% 和 47.9%）和增强的 EPS 产生（447.67 mg/ml 和 75.00 mg/ml），分别比对照、BHUJP-2 和 BHUJP-P1 分别增加。同时，与 BHUJP-2 和 BHUJP-P1 相比，这两种菌株在两种杀虫剂的 3×剂量下记录到最低的 PGP 活性和种子发芽减少。菌株 BHUJP-P3 和 BHUJP-P4 在 50mg/kg 浓度下分别降解久效磷 83%和 81%；在 150mg/kg 浓度下分别降解 81%和 80%，在 5 天内分别降解 81%和 80%。同时，这两种菌株 BHUJP-P3 和 BHUJP-P4 在 50mg/kg 浓度下分别降解氯吡硫磷 53%和 90%；在 72 小时内分别降解 49%和 87%，在 100mg/kg 浓度下分别降解 49%和 87%。在菌株 BHUJP-P3 和 BHUJP-P4 中发现了 OPs 杀虫剂降解基因 opdA 和 opd。菌株 BHUJP-P3 和 BHUJP-P4 的多种生物活性表现出对杀虫剂的最大耐受性，以及在杀虫剂胁迫下对植物生长促进和生物防治的 P 溶磷、IAA、铁载体和 HCN 产生的最小减少。因此，这些新分离株可用作有机磷杀虫剂的生物降解和植物促生细菌（PGPB）接种剂，以增强胁迫下蔬菜的种子发芽。这些新菌株将是环保、社会可接受和经济可行的。
