Foliar Supplementation of Recycled Phosphorus from Cattle Bone Meal Improves Soybean Growth Characteristics, Nutrient Content, and Chlorophyll Pigment Concentration

Plants can absorb only 30 to 40% of nutrients from the soil through the root system because the absorption process depends on soil properties, wheatear conditions, and the plant's species. Therefore, foliar fertilization using macro- and micronutrients has proven to be an excellent alternative. Herein, we evaluated the foliar application of a neutralized sulfuric bone meal hydrolysate (NSBMH) on soybean growth parameters, pod yield, nitrogen, phosphorus, and chlorophyll pigment concentrations under greenhouse conditions. A complete randomized block design was performed, and each block contained three treatments: 1% NSBMH, commercial fertilizer, and negative control. After 90 days of growth, soybean plants foliar-sprayed with 1% NSBMH improved significantly (p < 0.05) in terms of foliar area, plant fresh mass, plant dried mass, plant height, nitrogen, and chlorophyll a + b concentrations, while trifoliar leaf number, pod number, and pod fresh and dried masses were higher but not significant, and phosphorus concentration maintained suitable levels when compared to the negative control treatment. Additionally, the 1% NSBMH group presented similar and higher values, but not significant (p > 0.05), on the evaluated traits versus the commercial fertilizer treatment. Consequently, cattle bone recycling for the obtainment of alternative phosphorus as neutralized sulfuric bone meal hydrolysate is an excellent choice because it encourages the reutilization of anthropogenic waste, such as cattle bone waste, which protects the environment and reduces the soil and foliar application of mineral phosphoric fertilizers and reduces dependency on the main unsustainable fertilizer suppliers.

Automated summary

Plants can only absorb a limited amount of nutrients from the soil, so foliar fertilization using sulfuric bone meal hydrolysate has been proven to be a good alternative. In this study, the effects of foliar application of neutralized sulfuric bone meal hydrolysate on soybean growth parameters and nutrient concentrations were evaluated. Results showed that soybean plants treated with 1% NSBMH had significantly improved growth and nutrient concentrations compared to the control group. Therefore, recycling cattle bone waste to obtain alternative phosphorus through neutralized sulfuric bone meal hydrolysate is a sustainable and environmentally-friendly option.