Bacillus thuringiensis as microbial biopesticide: uses and application for sustainable agriculture

Abstract

Background Bacillus thuringiensis (Bt) has been used in agriculture for a long time because of its insecticidal proteins which make it a valuable environment-friendly biopesticide. However, its use is not only limited to insecticidal properties. Current and previous studies indicate its potential as a biofertilizer for promoting plant growth, the development of transgenic plants, and others. It is the presence of δ-endotoxins, especially cry protein, which attributes the insecticidal property to the bacteria. Besides, there are some vegetative and secreted insecticidal proteins that exert their toxic activity towards specific species. Main body of abstract The present review briefly provides an overview of the Bt uses and application as a biocontrol agent against insect pest for sustainable agriculture. Historical development of Bt as biocontrol, classification of various cry proteins, their mechanisms of actions against different insect-pest, and incorporation of cry genes in the plant for developing transgenic Bt plants such as Bt cotton, potato, and maize. Applications of Bt as biofertilizer and the various bioformulations as biopesticide are also described. Short conclusion Uses of harmful pesticides and chemical cause various health issues and environmental problem; therefore, the Bt served as the best alternative to overcome the above issue. Also, we aim to explore the potential as plant growth-promoting potential and solubilization of minerals and the uses as a biofertilizer, keeping the high specificity and environmental safety of Bt. Its various formulations are commercially available and considered an efficient alternative to chemical pesticides.

Expression of thurincin H, ChiA74 and Cry proteins at the sporulation phase in Bacillus thuringiensis HD1

“…In addition, B . thuringiensis is environmentally friendly, and this bacterium is used in combination with other strategies as part of modern pest management in agriculture (Kumar et al, 2021). B .…”

“…Cry proteins are highly toxic to a broad range of crop pests of a different order and against mosquitoes, which are vectors of human diseases, including dengue and malaria (Feitelson et al, 1992). In addition, B. thuringiensis is environmentally friendly, and this bacterium is used in combination with other strategies as part of modern pest management in agriculture (Kumar et al, 2021). B. thuringiensis strains are used to produce microbial insecticidal products (Azizoglu, 2019), based on Cry proteins and spores.…”

Functional characterization of multidomain protein Vip3Aa from Bacillus thuringiensis reveals a strategy to increase its insecticidal potency

“…Microbially derived insecticidal proteins are useful substitutes for synthetic pesticides due to their highly targeted insecticidal effects and more sustainable manners [1][2][3][4][5][6] . Bacillus thuringiensis (Bt) is the most broadly used microbial insecticide worldwide due to its production of highly effective Cry insecticidal proteins [7][8][9] , which account for over 75% of the microbial biopesticide market 10,11 . Cry proteins are produced by Bt during sporulation and are widely used for biological control of pest insects, in the form of transgenic crops and formulated sprays 7,[12][13][14][15][16][17] .…”

“…Bacillus thuringiensis (Bt) is the most broadly used microbial insecticide worldwide due to its production of highly effective Cry insecticidal proteins [7][8][9] , which account for over 75% of the microbial biopesticide market 10,11 . Cry proteins are produced by Bt during sporulation and are widely used for biological control of pest insects, in the form of transgenic crops and formulated sprays 7,[12][13][14][15][16][17] . However, the application of Cry proteins also has its limitations due to their singular composition, limited insecticidal spectrum, and increased development of resistance in target pests 1,2,8,10,[18][19][20] .…”

“…However, the application of Cry proteins also has its limitations due to their singular composition, limited insecticidal spectrum, and increased development of resistance in target pests 1,2,8,10,[18][19][20] . Therefore, the development of new effective insecticidal protein resources is imperative 3,4,7,10,21 .…”