Organic materials added to soil create anaerobic conditions that can reduce soil-borne pathogens that reduce the yield and quality of agricultural crops. Anaerobic soil disinfestation (ASD) requires relatively large quantities of readily available, inexpensive organic materials. We evaluated the impact of ASD with rice bran and biochar organic materials on changes to the soil’s physicochemical properties, microbial taxa, and strawberry fruit yield. We found that the organic materials applied at different dose rates significantly increased the control effect of the soil Fusarium spp. and Phytophthora spp. to 69–99% and 63–98%, respectively. In addition, ASD significantly increased soil organic matter and ammonium nitrogen contents. Strawberry yield also increased significantly after ASD treatment with biochar applied at 10 t/ha, which was positively correlated with increased soil nutrients and a significant reduction in pathogens. High-throughput gene sequencing showed that ASD significantly increased the abundance of some beneficial microorganisms such as Bacillus, Pseudomonas, and Mortierella, possibly due to changes in the soil’s physicochemical properties that favored their survival. We found for the first time that biochar applied at 10 t/ha could create anaerobic conditions that effectively reduced soil-borne pathogens and increased crop yield.

Soil fumigation can kill soil pathogens and solve the problem of crop continuous cropping. However, soil fumigation also has negative effects on the soil environment. One way to mitigate the negative effects is to apply soil amendments, but there is limited evidence of the effects of combining soil fumigation and amendments. This study was a controlled environmental pot trial. We measured the effects of dazomet fumigation combined with soil amendments on soil-borne pathogens, soil nutrients, enzyme activities, and strawberry growth. The results showed that dazomet fumigation combined with soil amendments significantly increased the content of ammonium nitrogen, available phosphorus and organic matter and increased soil activities by varying degrees. We also found that the control effect of soil-borne pathogens Fusarium spp. and Phytophthora spp. was further enhanced, reaching 88.97–96.88%. Correlation analysis showed that the growth indices of strawberries such as plant height, stem diameter, chlorophyll content, and fresh weight were negatively correlated with Fusarium spp. (R = −0.75, R= −0.62, R = −0.71, R = −0.88; p < 0.01) and Phytophthora spp. (R = −0.72, R= −0.72, R = −0.78, R = −0.91; p ≤ 0.001), respectively. The effect of fumigation combined with soil amendments was better than that of fumigation alone, and silicon fertilizer had the best effect. Our study suggests that dazomet fumigation combined with soil amendments can improve soil nutrient supply, activate soil enzyme activities, enhance the control effect of soil-borne pathogens, and thus promote strawberry growth.

The root-knot nematode (Meloidogyne incognita) is a plant pathogen that causes significant economic damage to important food crops. The nematicidal and insecticidal effects of the essential oil and extract of the root and stem of different species of Eupatorium have been studied in several countries. We investigated the impact of root stems and leaves of the E. adenophorum on the second-stage juveniles (J2s) of M. incognita. Nematode mortality decreased by root-stem treatment and increasing temperature and time. Nematodes (J2) were more sensitive to root-stem treatment than leaf treatment at all tested conditions. For example, the half maximal effective concentration (EC₅₀) root-stems at 35 °C was estimated as 10.3 mg/g and in the 8th week as 7.8 mg/g, while the maximal effective concentration (EC_max) in leaf treatment is 20.3 and 10.1 mg/g, respectively. The E. adenophorum 40 mg/g concentration of root stems also produced the highest height of the cucumber stem and the highest cucumber fresh weight in the greenhouse. (E)-beta-farnesene, α-pinene and D-limonene, as the main identified components in fumigant plants, increased the mortality rate of J2s in root-stems treatment. We conclude that E. adenophorum dried root stems added to the soil in greenhouses have the potential as a bio-fumigant for M. incognita management.

Seeds comprise an important way in which plant pathogens are introduced into new areas, and serve as carriers for their survival from one planting season to another. Seed health is a recognized factor in modern agricultural science, and affects ideal plant populations and good harvests. Seed disease is one of the most important biological constraints in seed production worldwide. Effective and rapid detection and identification methods for seed disease comprise an important step in crop management, and a measure to protect seeds from pathogens. The detection of seed diseases is usually divided into three categories: traditional detection, immunological detection, and bioinformatics-based detection. The detection methods used for different types of pathogens also vary. For the prevention and control of seed diseases, appropriate methods should also be adopted, such as physical methods, chemical methods, and biological methods. They can be used alone or in combination to achieve the purpose of disease prevention and control. Therefore, this article reviews some important crop seed diseases, their detection and identification methods, and control techniques, in order to provide a theoretical basis for the comprehensive prevention and effective control of seed diseases.

Meloidogyne spp. are important parasitic nematodes affecting a variety of plants worldwide. We investigated the nematicidal properties of specific compounds found in bio-fumigant plants, particularly linalool, nonanal, methylene chloride, and 2-Decanal. Laboratory findings revealed that methylene chloride and 2-Decenal effectively reduced populations of second-stage juveniles (J2s). Additionally, the research explored the effects of tomato (Solanum lycopersicum L.) on M. incognita J2s, observing that tomato leaves significantly increased J2 mortality for all time measurements and different temperatures, while the opposite results were observed for root-stems. In the study, leaf treatment resulted in a maximum mortality response (MR_max) and half-maximal effective concentration (EC₅₀) of approximately 100% and 4.0 µg/mg, respectively, at a temperature of 35 °C by week 8. In contrast, the root-stems treatment showed an MR_max of 13.5% and an EC₅₀ of 3.0 ± 1.7 µg/mg. GC-MS analysis identified key compounds in tomato leaves and root-stems, such as α-pinene, d-limonene, and linalool. The results suggest that tomato leaves have potential as effective bio-fumigants for controlling root-knot nematodes.

Fumigation of soil using chloropicrin has been proven to significantly affect soil nutrient cycling, but the mechanism by which soil potassium conversion and plant uptake is promoted remains unclear. In this study, we conducted a fumigation experiment to investigate the effects of chloropicrin soil fumigation on the conversion of soil potassium post-fumigation (days 7–70), and its mechanisms, tomatos were planted in fumigated and non-fumigated soils to enable further comparisons. Results showed that the content of rapidly available potassium and available potassium decreased by 16–24% and 17–23% at day 28 respectively, when tomato was planted in chloropicrin-fumigated soils compared to the non-fumigated soils. The potassium content of tomato planted in fumigated soil was significantly higher than that planted in non-fumigated soil (30.3 vs. 21.9 mg g⁻¹ dry weight). Chloropicrin fumigation resulted in a significant change in the soil bacterial and fungal community structures, and trigged a long-term (at least 70-day) decrease in microbial diversity. Network analysis showed that chloropicrin soil fumigation changed microbial co-occurrence patterns by decreasing bacterial total links, nodes, and average degree, and increasing fungal total links, nodes, and average degree. Chloropicrin fumigation caused significant changes in the relative abundance of Bacillus species, which are involved in potassium dissolution. Structural equation model (SEM) suggested that fumigation with chloropicrin enhanced the contribution of soil potassium to tomato growth and reduced the contribution of bacterial communities. Together, the results of our study help in understanding the crop yield enhancement mechanism of soil fumigation.