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Cao SK, Du XX, Chen G, Zeng AP, Yu H. Relative activity of 15 bacterial strains against the larvae of Helicoverpa armigera, Spodoptera exigua, and Spodoptera litura (Lepidoptera: Noctuidae). JOURNAL OF ECONOMIC ENTOMOLOGY 2023; 116:1505-1517. [PMID: 37499044 DOI: 10.1093/jee/toad147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 06/08/2023] [Accepted: 07/11/2023] [Indexed: 07/29/2023]
Abstract
Crystal toxins produced by different strains of entomopathogenic Bacillus thuringiensis (Bt) have been characterized and widely applied as commercial biological pesticides owing to their excellent insecticidal properties. This study aimed to identify novel bacterial strains effective in controlling Spodoptera exigua Hübner, Helicoverpa armigera Hübner, and Spodoptera litura Fabricius. Fifteen culturable bacterial strains were isolated from 60 dead larvae (H. armigera and S. exigua) collected in the field. The biochemical characteristics and 16S rRNA sequences of these strains indicated that one strain (B7) was Lysinibacillus sp., 12 strains (B1, B3, B4, B5, B6, B8, P2, P3, P4, P5, P6, and DW) were Bt kurstaki, and P2-2 and B2 were Bacillus velezensis subsp. Laboratory bioassays indicated that strains B3, P6, B6, and P4 showed high toxicity to second-instar larvae of S. exigua, with LC50 values of 5.11, 6.74, 205.82, and 595.93 µg/ml, respectively; while the strains P5, B5, B6, and P6, were the most efficient against second-instar larvae of H. armigera with LC50 values of 725.82, 11,022.72, 1,282.90, 2,005.28, respectively, and strains DW, P3, P2, and B4 had high insecticidal activity against second-instar larvae of S. litura with LC50 values of 576.69, 1,660.96, 6,309.42, and 5,486.10 µg/ml, respectively. In conclusion, several Bt kurstaki strains with good toxicity potential were isolated and identified in this study. These strains are expected to be useful for biointensive integrated pest management programs to reduce the use of synthetic insecticides.
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Affiliation(s)
- Sheng-Kai Cao
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Changsha, Hunan 410128, China
- College of Plant Protection, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Xing-Xing Du
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Changsha, Hunan 410128, China
- College of Plant Protection, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Gong Chen
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Changsha, Hunan 410128, China
- College of Plant Protection, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Ai-Ping Zeng
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Changsha, Hunan 410128, China
- College of Plant Protection, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Huan Yu
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Hunan Agricultural University, Changsha, Hunan 410128, China
- College of Plant Protection, Hunan Agricultural University, Changsha, Hunan 410128, China
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Soni R, Keharia H. Phytostimulation and biocontrol potential of Gram-positive endospore-forming Bacilli. PLANTA 2021; 254:49. [PMID: 34383174 DOI: 10.1007/s00425-021-03695-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 08/02/2021] [Indexed: 06/13/2023]
Abstract
The spore-forming Bacillus and Paenibacillus species represent the phyla of beneficial bacteria for application as agricultural inputs in form of effective phytostimulators, biofertilizers, and biocontrol agents. The members of the genera Bacillus and Paenibacillus isolated from several ecological habitats are been thoroughly dissected for their effective application in the development of sustainable and eco-friendly agriculture. Numerous Bacillus and Paenibacillus species are reported as plant growth-promoting bacteria influencing the health and productivity of the food crops. This review narrates the mechanisms utilized by these species to enhance bioavailability and/or facilitate the acquisition of nutrients by the host plant, modulate plant hormones, stimulate host defense and stress resistance mechanisms, exert antagonistic action against soil and airborne pathogens, and alleviate the plant health. The mechanisms employed by Bacillus and Paenibacillus are seldom mutually exclusive. The comprehensive and systematic exploration of the aforementioned mechanisms in conjunction with the field investigations may assist in the exploration and selection of an effective biofertilizer and a biocontrol agent. This review aims to gather and discuss the literature citing the applications of Bacillus and Paenibacillus in the management of sustainable agriculture.
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Affiliation(s)
- Riteshri Soni
- Department of Biosciences, UGC Centre of Advanced Study, Sardar Patel University, Satellite Campus, Vadtal Road, Bakrol, Anand, Gujarat, 388 315, India
| | - Hareshkumar Keharia
- Department of Biosciences, UGC Centre of Advanced Study, Sardar Patel University, Satellite Campus, Vadtal Road, Bakrol, Anand, Gujarat, 388 315, India.
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