Soybean Yield Response of Biochar-Regulated Soil Properties and Root Growth Strategy

Abstract

Continuous cropping obstacles limit soybean production. Biochar is beneficial for soybean growth, but it is unclear whether biochar performs a sustainable role in continuous cropping. To further explore the effects of biochar on soil properties and soybean growth, a ceramic Wagner pot-simulated field experiment was conducted with biochar at different doses (12, 24, and 48 t·ha−1) over a period of 3 years, no fertilizer, no biochar (CK) and fertilizer (F)treatments were used for comparison. The results showed that biochar significantly reduced soil bulk and improved the rhizosphere soil pH, available nutrients (N, K), and total nutrients (C, N, P, and K) compared with CK and F. Moreover, the soybean root length, surface area, volume, and exudates increased with biochar amendment. In particular, biochar significantly increased the nodule number, dry weight, and nitrogenase activity of soybean. Furthermore, biochar promoted soybean growth and increased soybean yield. In general, we found that the soybean yield increased with biochar and that biochar had a positive, sustainable effect on soil properties and soybean root growth, providing a new cultivation measure for soil health and soybean production in continuous cropping, which is very important for increasing soybean productivity to break the limitations of soybean traditional continuous cultivation.

Long term co‐application of biochar and fertilizer could increase soybean yield under continuous cropping: insights from photosynthetic physiology

“…Moreover, biochar is alkaline and can increase the availability of soil nutrients and facilitate crop nutrient uptake 33 . In addition, our previous studies have found that biochar application can increase effective soil nutrient content, improve continuous cropping soil pH and stimulate root growth and development 34 . This may enhance nutrient and water transport from roots to aboveground parts, ultimately increasing soybean leaf area and LAI.…”

“…Remarkably, BCAF was able to boost soybean output even in situations where fertilization was reduced by 50%. This primarily is explained by the possibility that applying fertilizer and biochar together could improve soil nutrient availability, raise soil nutrient content, and improve fertilizer utilization, thus providing adequate and effective nutrient supply for soybean growth and yield formation 34,48 . This would result in an adequate and efficient supply of nutrients for soybean development and yield creation.…”

“…33 In addition, our previous studies have found that biochar application can increase effective soil nutrient content, improve continuous cropping soil pH and stimulate root growth and development. 34 This may enhance nutrient and water transport from roots to aboveground parts, ultimately increasing soybean leaf area and LAI. Previous research had shown that biochar combined with chemical fertilizers could markedly increase leaf chlorophyll content and aboveground biomass.…”

“…This primarily is explained by the possibility that applying fertilizer and biochar together could improve soil nutrient availability, raise soil nutrient content, and improve fertilizer utilization, thus providing adequate and effective nutrient supply for soybean growth and yield formation. 34,48 This would result in an adequate and efficient supply of nutrients for soybean development and yield creation. In summary, BCAF can improve the metabolites, physiological functions and plant efficiency of continuous soybean photosynthesis, facilitate the accumulation of soybean photosynthetic products, increase leaf dry weight and ultimately increase soybean yield.…”

Characterization of isolated starch from Isatis indigotica Fort. root and anhydro-sugars preparation using its decoction residues

“…Meanwhile, the resulting biochar is a solid carbonaceous material with high aromatization, good stability, large specific surface area, rich pore structure, and strong adsorption capacity. It is widely used to improve soil fertility [ 41 , 42 ] and overcome obstacles for continuous cropping [ 43 , 44 ], and as a cost-effective adsorbent for sewage treatment [ 45 , 46 ].…”