Biochar and Intercropping With Potato–Onion Enhanced the Growth and Yield Advantages of Tomato by Regulating the Soil Properties, Nutrient Uptake, and Soil Microbial Community

Abstract

The application of biochar stimulates the activities of microorganisms that affect soil quality and plant growth. However, studies on the impacts of biochar mainly focus on a monoculture, its effects on interspecific interactions are rarely reported. Here, we investigated the impacts of biochar on tomato/potato–onion intercropped (TO) in a pot experiment. Tomato monoculture (T) and TO were treated with no, 0.3, 0.6, and 1.2% biochar concentrations in a pot experiment. Microbial communities from tomato rhizosphere soil were analyzed by quantitative PCR and Illumina MiSeq. The results showed that compared with the tomato monoculture, 0.6%TO and 1.2%TO significantly increased tomato yield in 2018. TO and 1.2%TO significantly increased plant height and dry weight in 2018 and 2019. Biochar treatments increased soil pH, decreased NO3--N and bulk density, and increased the absorption of N, P, and K by tomato. Bacterial and fungal abundances increased with an increase in biochar concentration, while Bacillus spp. and Pseudomonas spp. abundances showed an “increase-decrease-increase” trend. Biochar had a little effect on bacterial diversities but significantly lowered fungal diversities. TO, 0.6%TO, and 1.2%TO increased the potentially beneficial organisms (e.g., Pseudeurotium and Solirubrobacter) and lowered the potentially pathogenic organisms (e.g., Kribbella and Ilyonectria). Different concentrations of biochar affected the bacterial and fungal community structures. Redundancy analysis indicated that the bacterial community was strongly correlated with soil pH, NO3--N, and EC, while the fungal community was closely related to soil NO3--N and moisture. The network analysis showed that biochar and intercropping affected the symbiosis pattern of the microorganisms and increased the proportion of positive interactions and nitrifying microorganisms (Nitrospirae) in the microbial community. Overall, our results indicated that monoculture and intercropping with biochar improved soil physicochemical states and plant nutrient absorption, and regulated soil microbial communities, these were the main factors to promote tomato growth and increase tomato productivity.

Interactive Impact of Biochar and Arbuscular Mycorrhizal on Root Morphology, Physiological Properties of Fenugreek (Trigonella foenum-graecum L.) and Soil Enzymatic Activities

“…In general, biochar treatment increased plant height by 66.6%, leaf number by 45.1%, and nodule number by 35.9% over control treatment (Table 1). Several researchers have reported that biochar application improves plant growth, development, and yield in different plants [29,30,32,34,39]. Similarly, Saxena et al [27] found that root length, shoot length, and root biomass were positively impacted by biochar treatment, also seen by Zheng et al [64], where biochar treatment increased the plant biomass of Chinese cabbage.…”

“…Trupiano et al [34] found that morphological traits were enhanced in biochar applications (Figure 5). All reports discussed the beneficial effect that biochar is believed to help boost soil fertility by increasing soil acidity [27,30,32,34]. AMF are beneficial symbiotic fungi improving plant growth, development, and plant nutrient uptake in various crops.…”

“…It plays an important role in soil nutrient availability, adsorption, and soil enzyme activity [26][27][28][29]. He et al [30] indicated that biochar enhanced the absorption of nitrogen (N), phosphorus (P), and potassium (K) by tomato. According to many studies, biochar treatment on its own has led to higher enzyme activity in soils with an acidic or alkaline pH, for instance, alkaline phosphatase, alkaline phosphomonoesterase, phosphohydrolase, and lipase-esterase [31][32][33][34].…”

Bacterial biomarkers are linked more closely to wheat yield formation than overall bacteria in fertilized soil

“…The LNM treatment significantly decreased the abundance of some pathogenic biomarkers, such as Kribbella (ASV_181600) and Burkholderiaceae (ASV_161133, ASV_107576, ASV_467163, ASV_311539, ASV_175182), which were enriched in the excessive nitrogen treatment (HN) with low yield. Therefore, inorganic–organic mixed fertilizer application may alleviate the adverse effects of excessive nitrogen input on wheat yield and promote wheat growth from the bacterial perspective (He et al, 2021). However, a balance between the application of inorganic and organic fertilizer application in agroecosystems may be needed.…”

Rhizosphere element circling, multifunctionality, aboveground productivity and trade-offs are better predicted by rhizosphere rare taxa

“…Non-metric multidimensional scaling (NMDS) ( Jiao et al, 2017 ; Khashi u Rahman et al, 2021 ) was applied to simplify samples or OUTs in high-dimensional to low-dimensional space for location using the “metaMDS” function based on the Bray–Curtis distance ( He et al, 2021 ). Linear discriminant analysis (LDA) effect size (LEfSe) was run to determine the significantly enriched clades (LDA scores ≥ 2 and p < 0.05).…”