Maltose and Totally Impermeable Film Enhanced Suppression of Anaerobic Soil Disinfestation on Soilborne Pathogens and Increased Strawberry Yield

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Effects of Granule Size Ranges on Dazomet Degradation and Its Persistence with Different Environmental Factors

Pesticides are considered the most effective way to protect crops. However, irrational use has caused resources waste and environmental pollution. Dazomet (DZ) is a soil fumigant that has been used in many countries for decades, although it has caused occasional crop damage or insufficient control efficacy in some circumstances. In this study, the effects of DZ’s granule size and exposure to various environmental conditions on DZ degradation when used as a fumigant were demonstrated. The degradation rate of DZ was closely related to granule size. The half-life of larger DZ granules was longer than smaller granules with all studied environmental factors. The degradation rate decreased as the DZ usage (90–360 mg/kg) increased and different granule sizes showed the same variation trend. The half-life in each of the five granule size ranges tested decreased significantly as the temperature increased. DZ half-life decreased by 4.67–6.59 times as the temperature increased from 4 to 35 °C. Moreover, DZ usage and temperature affected the half-life of granules >400 and 300–400 μm in diameter significantly more than <100 μm granules. The half-life of all DZ granule sizes was reduced by 13.9–47.4% in alkaline compared to acidic conditions (pH from 9 to 5). Moreover, elevated temperatures could not only promote the production of methyl isothiocyanate (MITC) but accelerate its dissipation. The interactions between DZ granule size, dosage, temperature, and pH provide practical guidance on methods to improve DZ’s efficacy against pests and reduce the risk of phytotoxicity

Dimethyl disulfide (DMDS) as an effective soil fumigant against nematodes in China.

Root-knot nematode is an important soil pest in horticulture crops and constrains the protected cultivation development after methyl bromide (MB) was phased out in China. Dimethyl disulfide (DMDS) exhibits excellent efficacy against nematodes. Laboratory experiments and field trials were set up to clarify DMDS dose, efficacy, and yield. A dose-response experiment using three methods showed that DMDS presented high efficacy against the nematode Meloidogyne incongnita. The LC50 values of direct fumigation activity in the dessicator method were 0.086 and 0.070 mg L-1 for DMDS and 1,3-D, 29.865 and 18.851 mg L-1 for DMDS and 1,3-D of direct contact activity in the small tube method, 6.438 and 3.061 mg L-1 for DMDS and 1,3-D of soil fumigation activity in the soil fumigation method, respectively. The field trials indicated that DMDS showed an excellent efficacy of 80%-94% on root-knot nematode applied at 10-100 g m-2 on tomato in Tongzhou, Beijing. The crop yields showed no significant difference after applying 10-80 g m-2 DMDS. Results indicate that DMDS applied at 10 g m-2 for controlling root-knot nematode in Beijing is cost effective. In conclusion, DMDS is an excellent soil fumigant that can be used for controlling root-knot nematode and can be an potential novel alternative to MB in China

Effects of Granule Size Ranges on Dazomet Degradation and Its Persistence with Different Environmental Factors

Pesticides are considered the most effective way to protect crops. However, irrational use has caused resources waste and environmental pollution. Dazomet (DZ) is a soil fumigant that has been used in many countries for decades, although it has caused occasional crop damage or insufficient control efficacy in some circumstances. In this study, the effects of DZ’s granule size and exposure to various environmental conditions on DZ degradation when used as a fumigant were demonstrated. The degradation rate of DZ was closely related to granule size. The half-life of larger DZ granules was longer than smaller granules with all studied environmental factors. The degradation rate decreased as the DZ usage (90–360 mg/kg) increased and different granule sizes showed the same variation trend. The half-life in each of the five granule size ranges tested decreased significantly as the temperature increased. DZ half-life decreased by 4.67–6.59 times as the temperature increased from 4 to 35 °C. Moreover, DZ usage and temperature affected the half-life of granules >400 and 300–400 μm in diameter significantly more than <100 μm granules. The half-life of all DZ granule sizes was reduced by 13.9–47.4% in alkaline compared to acidic conditions (pH from 9 to 5). Moreover, elevated temperatures could not only promote the production of methyl isothiocyanate (MITC) but accelerate its dissipation. The interactions between DZ granule size, dosage, temperature, and pH provide practical guidance on methods to improve DZ’s efficacy against pests and reduce the risk of phytotoxicity

First-Principles Investigations of the Electronic Structure and Mechanical Characteristics of Nd³⁺-Doped YAlO₃ Crystals

Near-infrared laser radiation based on Nd3+-doped yttrium ortho-aluminate (Nd:YAlO3, Nd:YAP) has garnered significant interest regarding solid-state lasers. Nevertheless, the crystal microstructures and electronic characteristics of Nd:YAP are still unclear, and the unique physical properties underlying its enormous applications require clarification. In this study, we conducted first-principles calculations at the atomic level to explore the electronic properties and mechanical characteristics of both pure YAP and Nd3+-doped YAP. The results suggest that the substitution of the Y3+ ion site with the Nd3+ impurity ion induces slight structural distortion in the YAP crystal lattice. An impurity band emerges between the original conduction band and the valence band, attributed to the 4f orbital of the Nd3+ ion, exerting a substantial influence on the narrowing of the band gap. Through an analysis of the mechanical characteristics of both pure YAP and Nd:YAP, we conclude that the incorporation of Nd3+ atoms leads to a reduction in the mechanical properties of YAP to a certain extent. Our study can serve as a foundational data source for investigations into material performance, especially for the application of Nd:YAP in solid-state laser systems

Molecular Methods for Identification and Quantification of Foodborne Pathogens

Foodborne pathogens that enter the human food chain are a significant threat worldwide to human health. Timely and cost-effective detection of them became challenging for many countries that want to improve their detection and control of foodborne illness. We summarize simple, rapid, specific, and highly effective molecular technology that is used to detect and identify foodborne pathogens, including polymerase chain reaction, isothermal amplification, loop-mediated isothermal amplification, nucleic acid sequence-based amplification, as well as gene chip and gene probe technology. The principles of their operation, the research supporting their application, and the advantages and disadvantages of each technology are summarized

Oils extracted from Eupatorium adenophorum leaves show potential to control Phythium myriotylum in commercially-grown ginger.

Oils extracted from the leaves of Eupatorium adenophorum were tested in vitro and in vivo against the soilborne pathogen Pythium myriotylum which causes soft rot, a devastating disease of commercial ginger production in China. Twelve compounds accounting for 99.15% of the total oil composition were identified by GC-MS. The major components were 10Hβ-9-oxo-agerophorone (37.03%), 10Hα-9-oxo-agerophorone (37.73%) and 9-oxo-10, 11-dehydro-agerophorone (23.41%). Antifungal activity was tested by the poisoned food technique against P. myriotylum, indicating minimum inhibitory concentrations of 100μg/ml after 7 days incubation. In addition, the oil extracts greatly inhibited the formation of both wet and dry mycelial biomass. The combination of E. adenophorum oil extracts and synthetic fungicides showed a strong synergistic effect, inhibiting the mycelial growth in in vitro assays. The synergistic effect of oil extracts with fungicides could allow fungicides to be used at reduced rates in the future which has environmental advantages. Oil extracts applied at 160 and 200μg/ml concentrations to ginger rhizomes before inoculation with P. myriotylum significantly reduced the infection rate in ginger. Examination by light and transmission electron microscopy revealed that oil extracts caused swelling of the hyphae, disruption of the cell wall, degradation of the cytoplasmic organelles and shortening of the cytoplasmic inclusion. These results suggested that the plasma membrane and endomembrane systems of P. myriotylum were severely damaged by the oil extracts of E. adenophorum which offer significant potential for use as a fungicide to control P. myriotylum