Abstract
This study aimed to verify the potential of three Aspergillus and Bacillus species as growth promoters in cotton plants under greenhouse conditions. The experiment was conducted with a completely randomized design with seven treatments (six microorganisms plus one control) and five replicates until the flowering stage at 70 days after emergence. The inoculation of cotton plants with Bacillus velezensis (Bv188) and Bacillus subtilis (Bs248 and Bs290) had a positive effect on total nitrogen extraction (899.31, 962.18, and 755.41 mg N/kg dry matter, respectively) compared to the control (459.31 mg N/kg dry weight), total phosphorus extraction (121.94, 124.31, and 99.27 mg P/kg dry matter, respectively) compared to the control (65.10 mg P/kg dry matter), and total dry matter (41.08, 43.59, and 49.86 g/plant, respectively) compared to the control (26.70 g/plant), as well as biomass carbon (72.26, 35.18, and 14.7 mg/kg soil, respectively). Cotton plants inoculated with Aspergillus brasiliensis (F111), Aspergillus sydowii (F112), and Aspergillus sp. (versicolor section) (F113) had higher total nitrogen extraction (953.33, 812.59, and 891.62 mg N/kg dry matter, respectively) compared to the control (459.31 mg N/kg dry matter), a higher total phosphorus (122.30, 104.86, and 118.45 mg P/kg dry matter, respectively) compared to the control (65.10 mg P/kg dry matter), a higher total dry matter (37.52, 37.41, and 53.02 g/plant) compared to the control (26.70 g/plant), and greater respiratory activity (14.98, 10.43, and 7.11 mg CO2/100 g soil, respectively) compared to the control (3.5 mg CO2/100 g soil). The fungi A. brasiliensis (F111) and A. sydowii (F112) promoted higher phosphorus absorption by cotton plants, which was reflected by the lower amount of nutrients in the soil (7.10 and 16.96 g P/dm3 soil) than in the control (26.91 g P/dm3 soil). The results suggest that B. subtilis 248 promoted an increase in phosphorus extracted from the roots and total and phosphorous compounds from the root dry matter and increased the value of soil respiratory activity, and this bacterium could be used as an inoculant in cotton crops.
Highlights
Cotton (Gossypium spp.) is a crop of economic importance for Brazil because the country reached production of 2.49 million tons in the 2020/2021 harvest (CONAB, 2021)
Cotton plants inoculated with bacteria Bv188, Bs248, and Bs290 showed higher weight of the root dry matter (12.37, 15.03, and 20.60 g/plant, respectively) compared to the control (7.05 g/plant), of the shoot dry matter (28.71, 28.56, and 29.27 g/plant, respectively) compared to the control (19.65 g/plant), and of the total dry matter (41.08, 43.59, and 49.86 g/plant, respectively) compared to the control (26.70 g/plant) (Figure 3)
The nitrogen content in the shoot dry matter (10.16 g N/kg dry matter) (Figure 4A) and phosphorus content in the root dry matter (4.28 g P/kg dry matter) were higher in cotton plants inoculated with Bv188 (Figure 4B) and Bs248 (Figure 5A) compared to the control (20.02 N/kg dry matter)
Summary
Cotton (Gossypium spp.) is a crop of economic importance for Brazil because the country reached production of 2.49 million tons in the 2020/2021 harvest (CONAB, 2021). Global estimates indicate that between 85 and 90 million metric tons of nitrogen fertilizer are applied to soil every year, and 40–70% is lost by leaching, with only a small part used by plants; additional nitrogen fertilizer is applied to the soil (Good et al, 2004; Wu and Liu, 2008) Another nutrient that plays an important role in plants is phosphorus, which forms biological molecules; its low availability and high fixation in the soil are problems that lead to deficiencies; phosphorus is a limiting factor for plant growth (Anand et al, 2016). In view of the above, the nutritional requirements for cotton production can be addressed by using plant growth-promoting microorganisms (Diaz et al, 2019)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
