Efficacy and economics evaluation of seed rhizome treatment combined with preplant soil fumigation on ginger soilborne disease, plant growth, and yield promotion.

Background: Ginger (Zingiber officinale Roscoe) is widely planted around the world. Owing to continuous planting, ginger is seriously affected by soilborne fungi, bacteria, and nematodes. Although preplant soil fumigation is an effective prevention strategy of soilborne diseases, individual fumigant and technology could not provide effective control of ginger soilborne disease.

2-Hydroxypropyl-β-cyclodextrin encapsulates dimethyl disulfide producing a controlled release formulation.

Dimethyl disulfide (DMDS), a soil fumigant, is an effective, broad-spectrum compound that often replaces bromomethane (MB) in the prevention and treatment of soil-borne diseases. However, the disadvantages of DMDS include toxicity, volatility, pungent odor, risk of human exposure, and environmental pollution. Cyclodextrin (CD) has been widely used as a carrier of chemicals in many industries due to its functional advantages and safety.

Soil properties, presence of microorganisms, application dose, soil moisture and temperature influence the degradation rate of Allyl isothiocyanate in soil.

Allyl isothiocyanate (AITC) is a soil fumigant derived from plants that can effectively control soil-borne diseases. Fully understanding the impact of various factors on its degradation can contribute to its effectiveness against pests and diseases. First, orthogonal design determined the extraction method of AITC in soil, that is using ethyl acetate as the extraction reagent, vortexing for 1 min as the extraction method and holding for 30 min as the method time.

Effects of Fumigation with Allyl Isothiocyanate on Soil Microbial Diversity and Community Structure of Tomato.

As a substitute for methyl bromide, effects of allyl isothiocyanate (AITC) on nontarget microorganisms in soil are poorly understood. This study measured the half-life of AITC in the soil as well as its effects on the soil substrate-induced respiration (SIR) and on communities of soil bacteria and fungi. The results showed that AITC had a short half-life and a short-term inhibition of SIR; high-throughput sequencing analysis showed that AITC had less effect on bacterial than fungal communities.

Chloropicrin fumigation alters the soil phosphorus and the composition of the encoding alkaline phosphatase PhoD gene microbial community.

The transformation of phosphorus (P) compounds in soil depends largely on soil microbial communities and is sensitive to agricultural practices. However, the effects of soil fumigation on soil P, and microbes involved in P transformation, are unknown. Our results showed that chloropicrin (CP) fumigation significantly increased the available-P, Leached-P and active-P fractionation (inorganic P extracted from HO, NaHCO and NaOH) in Shangdong and Miyun soils in the early stages of culture, while soil alkaline phosphatase (ALP) activity and phoD gene abundance decreased significantly.

Effects of multi-year biofumigation on soil bacterial and fungal communities and strawberry yield.

Biofumigation is an effective, non-chemical method to control soil-borne pests and diseases and to maximize crop yield. We studied the responses of soil bacterial and fungal communities, the soil's nutritional state and strawberry yield, when the soil was biofumigated each year for five consecutive years using fresh chicken manure (BioFum). BioFum significantly increased the soil's NH-N, NO-N, available P and K and organic matter.

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.

Chloropicrin alternated with biofumigation increases crop yield and modifies soil bacterial and fungal communities in strawberry production.

Chloropicrin (Pic) and biofumigation are both considered effective chemical and non-chemical alternatives to methyl bromide, respectively, for controlling crop-limiting soil-borne pests and diseases. In this study, we evaluated the effects of Pic alone and 'chloropicrin alternated with biofumigation' (CAB) on the soil's physico-chemical properties and strawberry yield, as well as their effects on soil bacterial and fungal communities. The contents of NO-N, available phosphorus and potassium, and electrical conductivity were all significantly increased when CAB was used.

Evaluation of the influence of temperature and relative humidity on the permeability of four films to the fumigant dimethyl disulfide.

Dimethyl disulfide (DMDS) is an alternative fumigant to methyl bromide that was phased out globally due to its stratospheric ozone-depleting properties. Covering the surface of the soil with a plastic tarpaulin or 'barrier film' when using a soil fumigant is typically used to retain fumigants in the soil and to reduce emissions. Emission levels depend on the film's permeability, which varies mainly according to the film's material, the type of fumigant and the environmental conditions.

Soil fumigation alters adsorption and degradation behavior of pesticides in soil.

Many crops are produced using soil fumigation and chemical pesticides to control soil-borne fungi and bacterial diseases, nematodes and weeds. Fumigation of soil, however, may alter its ability to adsorb, degrade and volatilize pesticides, which can then change the potential for pesticides to leach into groundwater. Soil adsorption kinetics, Freundlich isothermal adsorption and pesticide degradation techniques were used to determine the potential for pesticides to pollute groundwater in fumigated soil.

Responses of Nitrogen-Cycling Microorganisms to Dazomet Fumigation.

The influence of soil fumigation on microorganisms involved in transforming nitrogen remains little understood, despite the use of fumigants for many decades to control soil-borne pathogens and plant-parasitic nematodes. We used real-time PCR (quantitative polymerase chain reaction) and 16S rRNA gene amplicon sequencing techniques to monitor changes in the diversity and community structure of microorganisms associated with nitrogen transfer after the soil was fumigated with dazomet (DZ). We also examined nitrous oxide (NO) emissions from these microorganisms present in fumigated fluvo-aquic soil and lateritic red soil.

Evidences of NO Emissions in Chloropicrin-Fumigated Soil.

The mechanism of NO production following chloropicrin (CP) fumigation was investigated in this study. Our results showed that CP fumigation increased NO production from 23 to 25 times in comparison with the control and significantly decreased the abundance of 16S rRNA and N-cycling functional genes. CP also decreased the soil bacterial diversity and caused a shift in the community composition.

Environmental Factors and Soil Amendment Affect the Decomposition Rate of Dazomet Fumigant.

Dazomet (3,5-dimethyl-1,3,5-thiadiazinane-2-thione) is widely used as a soil fumigant for controlling soil-borne diseases and pests in China and other agricultural countries. The active ingredient of dazomet is its degradation product, methyl isothiocyanate. Little is known about the environmental conditions that affect the degradation of dazomet in soil.

Changes in the abundance and community composition of different nitrogen cycling groups in response to fumigation with 1,3-dichloropropene.

The fumigant 1,3-dichloropropene (1,3-D) is widely-used to control pathogenic bacteria, fungi, nematodes and insects in soil before a crop is planted. Although fumigants in general have been reported to have a 'fertilizer effect' in the soil by increasing nitrogen availability, little is known of how a specific fumigant such as 1,3-D affects available nitrogen. This study used real-time quantitative PCR (qPCR) and 16S rRNA gene amplicon sequencing techniques to investigate the effects of 1,3-D on microorganisms involved in nitrogen cycling that were present in 2 soils: Jiangxi lateritic red soil and Beijing fluvo-aquic soil.

Effect of soil fumigants on degradation of abamectin and their combination synergistic effect to root-knot nematode.

Background: Root-knot nematode (Meloidogyne spp., RKN) causes a disease that significantly reduces the yield of greenhouse cucumber crops year after year. Chemical control based on a single pesticide is now unreliable mainly due to pest resistance.

Effects of oil extracts of Eupatorium adenophorum on Phytophthora capsici and other plant pathogenic fungi in vitro.

The antifungal activity of oils extracted from Eupatorium adenophorum was tested against five phytopathogens in vitro. Oil extracts inhibited the mycelial growth of Phytophthora capsici which causes phytophthora blight in pepper. The minimum inhibitory concentration of oils against P.

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.

Preparation of Main-Chain Polymers Based on Novel Monomers with D-π-A Structure for Application in Organic Second-Order Nonlinear Optical Materials with Good Long-Term Stability.

Main-chain nonlinear optical polymers based on novel chromophores with special structures presented good solubility in most of the organic solvents. Polymers PE-1 and PE-2 attained the thermal decomposition temperatures of 305 and 223 °C and glass transition temperatures of 113 and 108 °C, and exhibited only negligible decay in the SHG signal baked at 85 °C over hundreds of hours, respectively. The SHG coefficients of poled films from polymers PE-1 and PE-2 were 26.

Analysis of the inhibitory effects of chloropicrin fumigation on nitrification in various soil types.

Chloropicrin retards the conversion of ammonia to nitrite during the nitrification process in soil. In our study, the dynamic effect of chloropicrin fumigation on soil nitrification was evaluated in five different soil types to identify relationships between soil properties and the effect of fumigation on nitrification. Chloropicrin significantly inhibited nitrification in all soils; however, the recovery of nitrification varied greatly between the soils.

Degradation of dimethyl disulphide in soil with or without biochar amendment.

Background: Dimethyl disulphide (DMDS) is a new and effective alternative to methyl bromide for soil fumigation. The effect of biochar on the fate of DMDS in soil is not fully understood. The objective of this study was to determine the degradation kinetics of DMDS in different soils and evaluate the effect of biochar amendment on DMDS degradation using incubation experiments.

Genetic variation in the invasive weed Mikania micrantha (Asteraceae) suggests highways as corridors for its dispersal in southern China.

Background And Aims: Roads as corridors of seed or fruit spatial dispersal have major impacts on the establishment and spread of invasive species, but their precise role in population genetic variation remains poorly understood. The South American weed Mikania micrantha has spread rapidly across southern China since its introduction to the Shenzhen area in 1984. This study investigated how its genetic diversity is distributed along highways, and whether highways have acted as corridors for the rapid expansion of M.

The effects and mode of action of biochar on the degradation of methyl isothiocyanate in soil.

Biochar is used as a new type of fertilizer in agriculture; however, its effect on the fate of fumigants in soil is not fully understood. The objective of this study was to investigate the effects of biochar on methyl isothiocyanate (MITC) degradation in soil in laboratory incubation experiments, including the effects of biochar composition, amendment rate, moisture, temperature, soil sterilization and soil type. The dissipation pathways of MITC in biochars included adsorption and chemical degradation.

Recombinant Passenger Proteins Can Be Conveniently Purified by One-Step Affinity Chromatography.

Fusion tag is one of the best available tools to date for enhancement of the solubility or improvement of the expression level of recombinant proteins in Escherichia coli. Typically, two consecutive affinity purification steps are often necessitated for the purification of passenger proteins. As a fusion tag, acyl carrier protein (ACP) could greatly increase the soluble expression level of Glucokinase (GlcK), α-Amylase (Amy) and GFP.