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Verticillium wilt caused by the soil-borne pathogen is one of the most significant diseases affecting the yield of cotton and is almost incurable with chemical agents. For this reason, it will be inevitable to cultivate resistant varieties. In this direction, this study was carried out to determine the response of cotton varieties and inbred lines obtained from cotton breeding projects of the GAP International Agricultural Research and Training Center (GAPUTAEM) in Diyarbakır, Türkiye to Verticillium wilt disease. The trial was conducted in a randomized complete block design with four replications during the 2016 and 2017 cotton growing seasons. In the study, 12 advanced inbred lines (8, 20, 30, 34, 38, 57, 58, 63, 64, 8/4, 5/7, and 8/1) and 3 control varieties [Stoneville 468, Carmen (tolerant control), and Çukurova-1518 (sensitive-control)] were tested for the response to Verticillium wilt under naturally infected field conditions. Disease severity was determined in the leaf at 5-10% and 50-60% of the boll opening stages and in the stem section after harvest. Additionally, some yield parameters and fiber quality properties were investigated in the study. The results indicated that there were significant differences among genotypes for most of the investigated characteristics.It was determined that with regard to foliar disease index (FDI) as mentioned boll opening stages and disease index of stem cross-section (SDI) the most tolerant genotype was inbred line 38, while the most sensitive variety was Çukurova-1518. As a result of their low disease index value and high yield capacity, the inbred lines 30, 57, 38, and 20 were recommended. [ABSTRACT FROM AUTHOR]

Soil-transmitted Helminths (STH) are among the most prevalent parasitic diseases that impair childhood physical and mental growth, hence hindering economic development. The study was a crosssectional-designed survey, conducted in three districts in Sierra Leone between December and March 2022 on 625 individual farmers to determine: 1) the prevalence of soil-transmitted helminths; 2) the intensity of soil-transmitted helminths; 3) the effect of the prevalence and intensity on farm productivity, and 4) the implication of these effects on agricultural extension service delivery and the rural livelihood of the selected districts. Stool samples were collected from male and female farmers in fifteen chiefdoms in the selected districts and analyzed using the Kato-Katz technique. A total of 625 individuals were included, among whom 172 (27.0%) were vegetable farmers, 224 (35.8%) were tree-crop farmers and 226 (36.2%) were rice farmers. The result indicates a prevalence of parasitic infection among farmers shown by 58.4% eggs/ova in stool from the three districts. STH prevalence is higher in Bo (64.0%), Koinadugu (56.9%), and Kailahun (51,7%). STH infections, in various ways, affected extension services, delivery and the livelihoods of individual farmers. The recommendation is that farmers and children be periodically dewormed for STH infection in rural areas. [ABSTRACT FROM AUTHOR]

Grapevine crown gall (GCG), which is caused by tumorigenic Allorhizobium vitis (=Rhizobium vitis), is the most important bacterial disease in grapevine, and its economic impact on grapevine is very high. When young vines develop GCG, they often die, whereas older vines may show stress and poor growth depending on the severity of GCG, because GCG interferes with the vascular system of the grapevine trunk and prevents nutrient flow, leading to inferior growth and death. Viticultural practices and chemical control designed to inhibit GCG are only partially effective presently; thus, a biocontrol procedure could be a desirable and effective approach for GCG prevention. This article reviews the practical use of biocontrol options for GCG inhibition that involve using nonpathogenic and antagonistic A. vitis strains. In these studies, screening tests of biocontrol agents discovered nonpathogenic A. vitis strains VAR03-1, ARK-1, ARK-2, and ARK-3. After dipping grapevine roots in a suspension of candidate strains prior to planting in the field, treatment using ARK-1 was shown to significantly reduce the number of plants with GCG. A meta-analysis indicated that ARK-1 is very useful for controlling crown gall in various plant species, including grapevine. It was reported that when a mixture of ARK-1 and a tumorigenic strain was examined in grapevines, the expression levels of several virulence genes of the virulent strain were significantly lower. ARK-1 can reduce the pathogen population in grapevines and gall incidence. Moreover, ARK-1 can prime the induction of certain defense genes of grapevine. These results indicate that ARK-1 has a unique biocontrol mechanism and that it is a promising new biocontrol agent to control GCG. [ABSTRACT FROM AUTHOR]

Information on the infection incidence of blackleg-causing soft rot Pectobacteriaceae (BL-SRP) in potato crops grown from minitubers (PB1-crop) and the distribution of BL-SRP in individual plants was collected during a two-year survey conducted at five potato growers located in the Netherlands. In the last weeks before haulm destruction, leaves, stems, and tubers of 100 or 200 plants were analyzed separately for the presence of Pectobacterium parmentieri, P. brasiliense, P. atrosepticum, and Dickeya spp. Extracted plant parts enriched for BL-SRP were analyzed with TaqMan assays specific for the detection of blackleg-causing BL-SRP. In 2019, low incidences of P. parmentieri (1–6%) in leaves were found at four growing sites. At one farm, reactions were detected in TaqMan assays for D. zeae and D. chrysanthemi in leaves. In 2020, the crops of two growers were largely free from BL-SRP. At one farm, a high infection incidence (21%) was found for D. fangzhongdai in tubers. The isolated pathogen was able to cause potato blackleg. At two other farms, high infection incidences in tubers were found with P. brasiliense (35–39%) and P. parmentieri (12–19%), whereas the incidence of P. brasiliense in leaves was also high (8%). In conclusion, high infection incidences with BL-SRP in potatoes can be found in a PB1 crop at the end of the growing season. Infections in individual plants were found either in tubers or in leaves. The potential sources of initial infection are discussed. [ABSTRACT FROM AUTHOR]

Background: Soil-transmitted helminth (STH) infection is 1 of the 20 notable neglected tropical diseases according to the Centers for Disease Control and Prevention and World Health Organization. In 2010, it is estimated that 1.73 billion people are infected with STH globally, of which 70% of cases occur in Asia. To date, there is a dearth of published literature on the prevalence of STH infection throughout Malaysia. Objective: The objectives of this study are to review research activity on STH infection in Malaysia, to estimate the prevalence of STH infection among Malaysians, and to identify significant risk factors associated with the infection. This review aims to provide the current state of evidence pertaining to STH infections, focusing on the main areas, limitations, and biases of research and mapping out the morbidity distribution of the diseases and their causative agents, and to identify significant risk factors for preventive measures. Methods: We will conduct a scoping review based on the 6-stage structured framework developed by Arksey and O'Malley. A comprehensive search strategy focusing on STH infection will be executed using electronic databases (Scopus, PubMed, Web of Science, and Embase). A systematic approach for searching, screening, reviewing, and data extraction will be applied based on the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) guidelines. Mendeley software and Microsoft Excel will be used to manage the references and to remove duplicates. Relevant data from selected articles will be extracted using a standardized data extraction form. Results: A total of 164 potential manuscripts were retrieved. Data extraction is currently in progress and completion is expected by the end of 2022. Conclusions: Our scoping review will summarize the current state of research in this field and provide comprehensive information regarding STH infections in Malaysia for future reference. [ABSTRACT FROM AUTHOR]

A number of soil-borne fungi cause diseases in chilli crop that result in significant yield loss. Hence in the present study, S. puniceus RHPR9 was evaluated against soil borne pathogens such as Macrophomina phaseolina, Fusarium oxysporum, Phytophthora capsici and Sclerotium rolfsii. Strain RHPR9 was antagonistic to M. phaseolina (76±0.1%), F. oxysporum (62±0.1%), P. capsici (57±0.2%) and S. rolfsii (52±0.1%), with a severe inhibitory impact on fungal growth and development. Further evaluation against charcoal rot disease in chilli was done under greenhouse conditions and plant weight was recorded. In addition, enzymes (peroxidase (POX), polyphenol oxidase (PPO) and phenylalanine ammonia lyase (PAL)) responsible for induced resistance were characterized. It was observed that there was considerable increase of POX, PPO and PAL in chilli plants treated with S. puniceus when compared to control. This study elucidates that S. puniceus induced POX, PPO and PAL biosynthetic pathways and inhibited M. phaseolina and can be potential biocontrol agent. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the impact of the location of the pathogen inoculum on damage caused by Globisporangium (syn. Pythium) ultimum, Fusarium culmorum and Rhizoctonia solani in pot tests with maize. For this purpose, pathogen inoculum was added to potting substrate, and the resulting mix was used to fill the whole pot volume, the upper half, or the lower half of pots. The remaining volume was filled with non-inoculated substrate. In a second experimental approach, maize seeds were germinated in non-inoculated potting substrate and the seedlings were transferred to inoculated substrate. The seeds were untreated, treated with the chemical thiram, or treated with a bacterial or a fungal biocontrol agent. With each of the pathogens, the damage to the developing maize seedlings was the strongest when the seeds germinated in the inoculated potting substrate. When only the roots were in contact with the inoculum, there was limited damage by R. solani and F. culmorum, and no damage by G. ultimum. This implies that in experiments with artificial inoculation, the seeds should always be in immediate contact with the inoculum if a strong pathogenic effect is desired. Conversely, seed treatments must, in the first place, be able to protect the spermosphere, while the requirement to protect the roots at a distance from the seed seems to depend on the pathogen. [ABSTRACT FROM AUTHOR]

Information on the infection incidence of blackleg-causing soft rot Pectobacteriaceae (BL-SRP) in potato crops grown from minitubers (PB1-crop) and the distribution of BL-SRP in individual plants was collected during a two-year survey conducted at five potato growers located in the Netherlands. In the last weeks before haulm destruction, leaves, stems, and tubers of 100 or 200 plants were analyzed separately for the presence of Pectobacterium parmentieri, P. brasiliense, P. atrosepticum, and Dickeya spp. Extracted plant parts enriched for BL-SRP were analyzed with TaqMan assays specific for the detection of blackleg-causing BL-SRP. In 2019, low incidences of P. parmentieri (1–6%) in leaves were found at four growing sites. At one farm, reactions were detected in TaqMan assays for D. zeae and D. chrysanthemi in leaves. In 2020, the crops of two growers were largely free from BL-SRP. At one farm, a high infection incidence (21%) was found for D. fangzhongdai in tubers. The isolated pathogen was able to cause potato blackleg. At two other farms, high infection incidences in tubers were found with P. brasiliense (35–39%) and P. parmentieri (12–19%), whereas the incidence of P. brasiliense in leaves was also high (8%). In conclusion, high infection incidences with BL-SRP in potatoes can be found in a PB1 crop at the end of the growing season. Infections in individual plants were found either in tubers or in leaves. The potential sources of initial infection are discussed.

Ginseng is an important cash crop. The long-term continuous cropping of ginseng causes the imbalance of soil environment and the exacerbation of soil-borne diseases, which affects the healthy development of ginseng industry. In this study, ginseng continuous cropping soil was treated with microbial inocula using broad-spectrum biocontrol microbial strain Frankia F1. Wheat straw, rice straw and corn straw were the best carrier materials for microbial inoculum. After treatment with microbial inoculum prepared with corn straw biochar, the soil pH value, organic matter, total nitrogen, available nitrogen, available phosphorus, and available potassium were increased by 11.18%, 55.43%, 33.07%, 26.70%, 16.40%, and 9.10%, the activities of soil urease, catalase and sucrase increased by 52.73%, 16.80% and 43.80%, respectively. A Metagenomics showed that after the application of microbial inoculum prepared with corn straw biochar, soil microbial OTUs, Chao1 index, Shannon index, and Simpson index increased by 19.86%, 16.05%, 28.83%, and 3.16%, respectively. Three classes (Alphaproteobacteria, Gammaproteobacteria and Sphingobacteria) were the dominant bacteria in ginseng soil, and their abundance increased by 7.87%, 9.81% and 1.24%, respectively, after treatment with microbial inoculum with corn straw biochar. Results indicated that the most effective treatment in ginseng soil would be the combined application of corn straw biochar and Frankia F1. [ABSTRACT FROM AUTHOR]

Crop rotations are widely used because they can significantly reduce the incidence of pests and diseases. The interactions between non-host roots and pathogens may be key in the inhibition of soilborne pathogens in crop rotations. Interactions between fennel (Foeniculum vulgare) roots/root exudates and Phytophthora nicotianae were investigated because of the known allelopathy between fennel and tobacco (Nicotiana tabacum). The effects of the key compounds in the fennel rhizosphere on the mycelial growth and zoospore behavior of P. nicotianae were assessed. The roots of fennel attracted P. nicotianae zoospores and inhibited their motility and the germination of cystospores, with some cystospores rupturing. 4-ethylacetophenone, vanillin and N-formylpiperidine were consistently identified in the fennel rhizosphere and were found to interfere with the infection of P. nicotianae, especially vanillin. Hyphae treated with these compounds produced more abnormal branches and accumulated reactive oxygen species. These interspecific interactions between non-host roots and pathogens were found to be an important factor in the inhibition by fennel of infection by P. nicotianae. [ABSTRACT FROM AUTHOR]

Objective In order to understand and analyze the pollution degree and common types of soil-borne parasites in the soil of different regions of Shaoguan City, we provide scientific basis for people to carry out parasite control activities. Methods Using the five-point sampling method, a total of 900 soil samples from different areas of East (Wujiang District), North (Zhenjiang District), Middle (Qujiang District) in Shaoguan City were collected from May to October 2019. The water washing precipitation method, the sodium chloride saturated solution floating method and the test tube filter paper culture method were used to detect the native parasitic soil standards. Insect pollution, microscopic examination was used to distinguish the types of soil-borne parasites detected, and SPSS 21.0 statistical software was used to process and analyze the data. Results The detection rate of worms in 900 soil samples was 18.78% (169/900), and the detection results in the three districts were 23.30% (48/206) in Wujiang District, 8.85% (23/260) in Qujiang District, and 22.58% (98/434) in Zhenjiang District (P<0.05). The sampled land was divided into different land types (planting cultivated land, around public toilets, surrounding parks, roadside green belts, and surrounding residential areas). The land type with the highest detection rate was cultivated land. The detection rate was 21.37% (140/655), followed by the soil around residential areas, which was 15.66% (13/ 83); the detected worm species were hookworm, roundworm, Trichostrongylus orientalis, whipworm, lung fluke, Fasciolopsis buski, Strongyloides stercoralis; and hookworms were detected the most, with a detection rate of 14.11% (127/900), followed by roundworms, with a detection rate of 2.11% (19/900). There were significant differences in the total detection rate, the detection rate of worms in cultivated land in each district, the detection rate of worms around public toilets in each district, the detection rate of hookworms in each district, and the detection rate of worms in each district. Conclusion There are still many kinds of parasitic worms in the soil of Shaoguan City. The management of human and animal excrement, the sanitation of the production and living environment of the residents, and the publicity and education of the prevention and control of parasitic diseases should be strengthened, and spreading of the parasitic diseases should be effectively controlled. [ABSTRACT FROM AUTHOR]

During a survey of oomycetes in ornamental plants carried out at the University of Aberdeen in 2014–2015, Pythium kashmirense was isolated from a specimen of Viburnum plicatum ‘Lanarth’, the first report of this oomycete in the UK (and in Europe). Pathogenicity of a Py. kashmirense isolate was examined using a range of plant species. Inoculations were carried out under controlled conditions in the absence of other Pythium and Phytophthora species, on Glycine max (soya bean), Phaseolus vulgaris (common bean), Lupinus angustifolius (blue lupin), Cucumis sativa (cucumber) and Viburnum opulus. The majority of inoculations caused pre-emergence damping-off, as well as seed rot and root rot. In the in vitro assays, germination rates (%) of soya bean and blue lupin seeds were less than 50%; in the in vivo inoculations on plants, over 50% of soya bean, blue lupin and common bean plants died; in contrast, cucumber plants showed lower susceptibility in pathogenicity tests, with an approximately 80% germination rate in in vitro tests, and 25% dead plants in the in planta inoculations. Inoculations carried out on root systems of Viburnum opulus caused severe necrosis and root rot. Little research was previously conducted on pathogenicity of Py. kashmirense and its relationship with losses in crop yield and quality. The present study showed varying virulence on the different plant species tested after inoculation with Py. kashmirense. Despite the lack of clear host specialization, infection by Py. kashmirense decreased seedling survival and health of plants in a range of important agricultural and ornamental plant species. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the impact of the location of the pathogen inoculum on damage caused by Globisporangium (syn. Pythium) ultimum, Fusarium culmorum and Rhizoctonia solani in pot tests with maize. For this purpose, pathogen inoculum was added to potting substrate, and the resulting mix was used to fill the whole pot volume, the upper half, or the lower half of pots. The remaining volume was filled with non-inoculated substrate. In a second experimental approach, maize seeds were germinated in non-inoculated potting substrate and the seedlings were transferred to inoculated substrate. The seeds were untreated, treated with the chemical thiram, or treated with a bacterial or a fungal biocontrol agent. With each of the pathogens, the damage to the developing maize seedlings was the strongest when the seeds germinated in the inoculated potting substrate. When only the roots were in contact with the inoculum, there was limited damage by R. solani and F. culmorum, and no damage by G. ultimum. This implies that in experiments with artificial inoculation, the seeds should always be in immediate contact with the inoculum if a strong pathogenic effect is desired. Conversely, seed treatments must, in the first place, be able to protect the spermosphere, while the requirement to protect the roots at a distance from the seed seems to depend on the pathogen.

Of ten actinobacterial isolates, Streptomyces cellulosae Actino 48 exhibited the strongest suppression of Sclerotium rolfsii mycelium growth and the highest chitinase enzyme production (49.2 U L−1 min−1 ). The interaction between Actino 48 and S. rolfsii was studied by scanning electron microscope (SEM), which revealed many abnormalities, malformations, and injuries of the hypha, with large loss of S. rolfsii mycelia density and mass. Three talc-based formulations with culture broth, cell-free supernatant, and cell pellet suspension of chitinase-producing Actino 48 were characterized using SEM, Fourier transform infrared spectroscopy (FTIR), and a particle size analyzer. All formulations were evaluated as biocontrol agents for reducing damping-off, root rot, and pods rot diseases of peanut caused by S. rolfsii under greenhouse and open-field conditions. The talc-based culture broth formulation was the most effective soil treatment, which decreased the percentage of peanut diseases under greenhouse and open-field conditions during two successive seasons. The culture broth formulation showed the highest increase in the dry weight of peanut shoots, root systems, and yielded pods. The transcriptional levels of three defense-related genes (PR-1, PR-3, and POD) were elevated in the culture broth formulation treatment compared with other formulations. Subsequently, the bio-friendly talc-based culture broth formulation of chitinase-producing Actino 48 could potentially be used as a biocontrol agent for controlling peanut soil-borne diseases caused by S. rolfsii. View Full-Text [ABSTRACT FROM AUTHOR]

'KS Silverado' (Reg. no. CV‐1175, PI 693936) hard white winter wheat (Triticum aestivum L.) was developed at the Agricultural Research Center–Hays, Kansas State University, and released by the Kansas Agricultural Experiment Station in 2019. KS Silverado was selected from a three‐way cross KS05HW122‐5‐2//KS05HW15‐2‐2/KS06HW46‐3 made in 2008 at Hays, KS. The objective of this cross was to develop a hard white winter wheat cultivar that is adapted to Kansas. KS Silverado was selected as an F6–derived line using a modified bulk method and tested in yield trials across Kansas for five years. KS Silverado is medium‐early and medium‐short and has good straw strength, above average grain volume weight, and very competitive grain yield in western and central Kansas. KS Silverado is tolerant to preharvest sprouting and has a good resistance package to diseases and insects, including Wheat streak mosaic virus, leaf rust, Soilborne wheat mosaic virus, and Hessian fly. It also has good milling and bread‐making qualities. [ABSTRACT FROM AUTHOR]

Background: Soil-transmitted helminth (STH) infection is a neglected tropical disease affecting approximately 1.5 billion people worldwide. In past decades, most studies focused on STH infection in preschool-aged and school-aged children in different regions of Thailand. However, little is known about the prevalence and intensity of STH infection in the elderly population. Therefore, the aim of this study was to determine the current prevalence and intensity of STH infections and to identify associated risk factors among the elderly population.Methods: A cross-sectional study was conducted from July to November 2019 to assess the prevalence of STH infections and associated risk factors among elderly populations living in five subdistricts of Thasala District, Nakhon Si Thammarat Province, Thailand. A total of 439 elderly individuals were selected using a random sampling technique. Each fresh stool sample was examined using the formalin ethyl acetate concentration technique (FECT), Kato-Katz thick smears and agar plate culture (APC). A structured questionnaire was used to obtain relevant information regarding associated risk factors for STH infection.Results: The overall prevalence of STH infection was 15.7%. Hookworms (10.9%, 48/439) were the most prevalent STH species, followed by Strongyloides stercoralis (3.4%, 15/439) and Trichuris trichiura (2.1%, 9/439). Most elderly individuals infected with hookworms or T. trichiura had light-intensity infections. A higher prevalence of STH infection was observed among individuals aged older than 80 years (23.4%) than among those aged between 70 and 79 years (15.2%) and 60-69 years (14.5%). Males were 1.85-times more likely to present with STH infections than females. Not washing vegetables before eating increased the risk of STH infection by 3.19 times, while defecation in an open field increased the risk of STH infection by 2.65 times.Conclusions: The findings suggested that STH infection is prevalent, and that hookworms are the most common STH species among elderly populations in southern Thailand. Personal hygiene and deworming programs should be implemented among the elderly population to reduce the risk and prevent the spread of STH infections. [ABSTRACT FROM AUTHOR]

Fungal species from the genus Fusarium are important soil-borne pathogens worldwide, causing significant economic losses in diverse crops. The need to find sustainable solutions against this disease has led to the development of new strategies--for instance, the use of biocontrol agents. In this regard, non-pathogenic Fusarium isolates have demonstrated their ability to help other plants withstand subsequent pathogen attacks. In the present work, several Fusarium isolates were evaluated in climatic chambers to identify those presenting low or non-pathogenic behavior. The inoculation with a low-pathogenic isolate of the fungus did not affect the development of the plant, contrary to the results observed in plants inoculated with pathogenic isolates. The expression of defense-related genes was evaluated and compared between plants inoculated with pathogenic and low-pathogenic Fusarium isolates. Low-pathogenic isolates caused a general downregulation of several plant defense-related genes, while pathogenic ones produced an upregulation of these genes. This kind of response to low-pathogenic fungal isolates has been already described for other plant species and fungal pathogens, being related to enhanced tolerance to later pathogen attacks. The results here presented suggest that low-pathogenic F. oxysporum and F. solani isolates may have potential biocontrol activity against bean pathogens via induced and systemic responses in the plant. [ABSTRACT FROM AUTHOR]

Abstract Continuous monocropping often influences negatively the soil microbial community and leads to the occurrence of soil-borne diseases. In this study, a pre-cultivation soil management strategy, reductive soil disinfestation (RSD), involving amendment by the use of reed straw, bagasse, and rice straw, and creating anaerobic soil conditions, was used to regulate the microbial community in a soil infested by Fusarium wilt of lisianthus and make it suitable for plant cultivation. The results showed that RSD significantly decreased F. oxysporum population by 97.1%–99.1% and the incidence of lisianthus wilt disease to 3.0%–14.3% compared with that of the untreated soil. The lowest disease incidence was found in the soil treated with RSD where bagasse was incorporated. The replantation of the host plant differently stimulated the pathogen proliferations across the different soils. MiSeq sequencing and culture-dependent investigation showed that the RSD treatments established distinct microbial communities compared to that of the untreated soil. Furthermore, the relative abundances of representatives of the families Cytophagaceae, Chitinophagaceae, Chaetomiaceae, and an unclassified family within Sordariomycetes, as well as soil microbial activity and the proportions of antagonists were significantly and negatively correlated with the pathogen population increase. Overall, the RSD treatment contributed to the reassembly of the soil microbiome which contained more beneficial agents that successfully controlled the pathogen inoculum level and lisianthus Fusarium wilt disease. [ABSTRACT FROM AUTHOR]

Grafting tomato (Solanum lycopersicum L.) onto disease resistant rootstocks has grown in use in North America over the past two decades. Rootstocks have traditionally been bred and used for their resistance packages to numerous soil-borne diseases but some rootstocks appear to improve scion yield and vigour in comparison to non-grafted plants in conditions lacking disease challenge. In this study, the tomato rootstocks 'Maxifort' or 'RST-106' were used to determine if vigour improved 'Tribute' scion traits, especially yield, and if marketable yield could be maintained in grafted plants at reduced nitrogen fertiliser inputs. Plants were grown in an open-field plasticulture production system at five rates of nitrogen from 0 kg ha−1 to 224 kg ha−1 applied via drip irrigation. Marketable yield was significantly affected by nitrogen rate and rootstock in both years. 'Tribute' grafted onto 'Maxifort' rootstock had the greatest, most consistent impact and increased marketable yield 15% and 30% in 2013 and 2014, respectively, compared to the non-grafted 'Tribute'. Our findings suggest that some rootstocks can increase scion growth and yield but do not differentially respond to decreased nitrogen rates. [ABSTRACT FROM AUTHOR]

Strongyloides stercoralis (S. stercoralis) is a soil-borne helminth but its prevalence in water samples is underestimated. The aim of the present study is to propose non-nutrient agar (NNA) as a novel culture method in the diagnosis of Strongyloides and to detect the prevalence rate of S. stercoralis larvae in tap water samples in Beni-Suef Governorate, Egypt. Eighty tap water samples were collected from Beni-Suef Governorate and each sample was filtered in three steps using three filters: one filter for microscopic examination of wet mount, while the remaining two filters were cultured on both NNA and nutrient agar plate (APC). S. stercoralis larvae, adults, and eggs were detected in two (2.5%) and four (5%) out of 80 samples after examination of wet mount preparation and cultures on both NNA and APC, respectively. NNA succeeded to maintain Strongyloides alive for up to 1 month. Our study is the first to detect Strongyloides larvae in tap water in Egypt and the first to use NNA as a novel culture media for Strongyloides. [ABSTRACT FROM AUTHOR]

An improved understanding of the conditions that influence dimethyl disulfide (DMDS) emissions, distribution through the soil and residues remaining after treatment will help to optimise the use of this relatively new soil fumigant for the control of soil-borne pests and disease, and to improve the safety of DMDS use. Using soil columns in the laboratory, the cumulative emission of DMDS using doses of 40 and 80 g m −2 were, respectively, 74.8% and 68.9% with bare soil, 4.2% and 9.6% with polyethylene (PE) film, 0.02% and 0.2% with Totally Impermeable Film (TIF). Six hours after injection DMDS was detected mostly 5 cm below the surface and very little at 25 cm when used on bare soil, compared with much higher and similar concentrations of DMDS 5 and 25 cm deep when films were used. DMDS at the injection port exceeded 1 µg cm −3 for longer when a film was used instead of bare soil. The total DMDS soil residues remaining in the soil, as a percentage of the initial DMDS dose at 40 or 80 g m −2 were, respectively, 1.17 and 5.58 with TIF, 0.91 and 1.18 with PE, 0.47 and 0.47 with bare soil. DMDS rose rapidly upwards and escaped from bare soil, whereas PE or TIF significantly reduced DMDS emissions, retained elevated DMDS concentrations in the soil for longer and distributed them more uniformly in the soil. TIF performed better in these respects than PE. TIF also reduced the potential environmental impact of DMDS more than PE, especially at the higher dose. [ABSTRACT FROM AUTHOR]

The biotrophic soil-borne fungus Tilletia horrida causes rice kernel smut, an important disease affecting the production of rice male sterile lines in most hybrid rice growing regions of the world. There are no successful ways of controlling this disease and there has been little study of mechanisms of resistance to T. horrida. Based on transcriptional data of different infection time points, we found 23, 782 and 23, 718 differentially expressed genes (fragments per kilobase of transcript sequence per million, FPKM >1) in Jiangcheng 3A (resistant to T. horrida) and 9311A (susceptible to T. horrida), respectively. In order to illuminate the differential responses of the two rice male sterile lines to T. horrida, we identified gene co-expression modules using the method of weighted gene co-expression network analysis (WGCNA) and compared the different biological functions of gene co-expression networks in key modules at different infection time points. The results indicated that gene co-expression networks in the two rice genotypes were different and that genes contained in some modules of the two groups may play important roles in resistance to T. horrida, such as DTH8 and OsHop/Sti1a. Furthermore, these results provide a global view of the responses of two different phenotypes to T. horrida, and assist our understanding of the regulation of expression changes after T. horrida infection. [ABSTRACT FROM AUTHOR]

Soil-transmitted helminthiases (STHs) constitute a public health problem that requires immediate action to resolve the morbidity of those harboring the parasites in their guts, to prevent infection in all those at risk, and to interrupt the vicious circle of poverty and disease in the affected communities, structural poverty being the main determinant of this group of infectious diseases. Since the times of the Rockefeller initiatives over a hundred years ago, the strategy has been viewed as one requiring community-wide efforts rather than pure individual case management. The World Health Organization (WHO) and its regional offices, as the governing institutions endorsed by the countries and their governments, have been the leaders in stating the actual executive measures to reach the goals and endpoints for the management of the problem. With the task of setting a group of activities that could be launched, monitored, and measured, these actions were established with the available resources since this public health problem had to be launched immediately, resources were those available at the moment and not those appearing on a wish list. Considerable progress has been made in the establishment of policies for the achievement of the Millennium Development Goals (MDGs), later followed by the Sustainable Development Goals (SDGs) through WHO-lead actions for the control of neglected tropical diseases (NTDs). With an initial goal of morbidity control, there are already discussions and proposals for elimination of STH if support is sustained and empiric facts confirm data emerging from modeling and small-scale studies. The aim of these comments is to describe and question instances of currently accepted concepts, theories, and practices that conform to the dogmatic status quo that serves as the foundation on top of which the new elimination aspirations are supposed to be built on, which might not be serving the desired purpose if taken unrevised. [ABSTRACT FROM AUTHOR]

Agricultural production is increasingly based on monoculture farming in Lithuania, which inevitably exacerbates the problems caused by a rising incidence of soil borne diseases. Take-all ( Gaeumannomyces graminis ), formerly a minor disease, has become common causing substantial damage to winter wheat and winter barley. The aim of the present study was to analyze the influence of different rotation sequences on take-all occurrence and to investigate disease control options with seed treatment fungicides fluquinconazole and silthiofam during the 2014–2015 growing seasons. The total amount of Gaeumannomyces graminis var . tritici ( Ggt ) and G. graminis var. avenae ( Gga ) DNA in the roots of winter wheat seedlings grown in the soil collected from different rotations was measured. Significantly higher DNA concentrations of Ggt/Gga were detected in the roots of seedlings grown in the soil of winter barley monoculture, compared to the winter wheat monoculture. Comparable amount of Ggt / Gga DNA in winter wheat seedlings was determined in the soil of winter wheat monoculture and winter wheat after oil seed rape (OSR) in both seasons, while in the second winter wheat it was considerably lower. Higher take-all incidence and disease index were established in winter barley than in winter wheat monoculture. Nevertheless in the rotation with one-year OSR, take-all incidence and disease index were significantly reduced compared to the monoculture and second winter wheat. The highest grain yield of winter wheat in both years was achieved in the rotation with OSR. The tested seed treatment fungicides fluquinconazole and silthiofam resulted in a significant reduction in take-all occurrence and a slight increase in grain yield. The findings of this study demonstrate that the OSR was the most valuable tool for management of take-all in wheat. [ABSTRACT FROM AUTHOR]

A new podovirus RsPod1EGY Ralstonia phage (GenBank accession no MG711516) with a specific action against R. solanacearum phylotype IIa, sequevar I (race 3, biovar 2) was isolated from Egyptian soil. The potential efficacy of the isolated phage to be used as biocontrol agent was evaluated in vitro and under greenhouse conditions. The podovirus phage produced a plaque size of 3.0–4.0 mm in diameter and completed its infection cycle in 180 min after infection with a burst size of ∼27 virions per infected cell. On the basis of restriction endonuclease analysis, the genome size of the phage was about 41 kb of double‐stranded DNA. In vitro studies showed that RsPod1EGY is stable at higher temperatures (up to 60 °C), and at a wide pH range (5–9). SDS–PAGE analysis indicated the major structural protein to be approximately 32 kDa. Bacteriolytic activity of RsPod1EGY against R. solanacearum was detected at different multiplicity of infection (MOI). RsPod1EGY proved to be effective in reduction and prevention of formation of surface polysaccharides of R. solanacearum, during the exponential growth phase of the latter. Interestingly, RsPod1EGY was effective in suppression of R. solanacearum under greenhouse conditions. All Phage‐treated tomato plants showed no wilt symptoms or any latent infection during the experimental period, whereas all untreated plants have wilted by 10 days post‐infection. The lytic stability of RsPod1EGY phage at higher temperature as well as its effective suppression of wilting symptoms under greenhouse conditions would contribute to biocontrol the bacterial wilt disease in Egypt under field conditions. [ABSTRACT FROM AUTHOR]

Objective: To review current evidence on infections related to the concentration of soil-transmitted helminth (STH) eggs in wastewater, sludge and vegetables irrigated with wastewater or grown on sludge-amended soils.Method: Search of Web of Science, Science Direct, PubMed and Google Scholar databases for publications reporting on STH egg concentration in wastewater, sludge and vegetables and for epidemiological studies on wastewater/sludge reuse and STH infections.Results: STH egg concentrations were variable but high in wastewater and sludge especially in developing countries. They ranged from 6 to 16 000 eggs/L in wastewater and from 0 to 23 000 eggs/g in sludge and far exceed limits set in the WHO guideline for wastewater/sludge reuse. Numbers of STH eggs on vegetables ranged from 0 to 100 eggs/g. The concentration of STH eggs in wastewater, sludge and vegetables therefore relates to risks of infection through different exposure routes.Conclusion: Epidemiological evidence reveals an increased prevalence of STH infections associated with direct exposure to wastewater or sludge (farmers) and consumption of vegetables grown on soil treated with it. This calls for increased efforts to reduce the adverse health impact of wastewater and sludge reuse in line with the WHO multi-barrier approach. [ABSTRACT FROM AUTHOR]

Soil-borne disease management in California strawberry production systems has historically relied upon pre-plant soil fumigation. Restricted efficacy of currently available fumigant chemistries towards certain pathogens and regulatory action requiring increased buffer zones has stimulated interest in development of alternative disease control strategies. Anaerobic soil disinfestation (ASD) demonstrates activity toward an array of soil-borne pathogens, however, there exist limited field-scale trials examining efficacy in strawberry systems. Multiple mechanisms, including the activity of an altered soil microbiome, are reported to function in ASD-induced disease suppression but consistency of the microbial response across soils has not been examined. The present research reports ASD-induced changes in composition of the soil microbiome which occurred in a carbon input-dependent manner and were consistent in two of the three field trials conducted. At all three field sites, ASD treatments that transformed the microbiome were consistently associated with enhanced strawberry yields, but specific compositional attributes of the microbiome in effective treatments were not uniform among all sites. Enhanced yields were associated with control of specific soil-borne pathogens at a given site, however disease control was not uniformly attained across all pathogens resident to a given soil system. Findings demonstrate that informed selection of substrate to be used in ASD and knowledge of the targeted pathogen profile resident to the strawberry field soil will be essential to successful use of ASD in commercial agricultural production settings. [ABSTRACT FROM AUTHOR]

The spread of antibiotic-resistant microorganisms is one of the biggest problems, for the solution of which is necessary a detailed study of this process. We detected the presence of pathogenic bacteria in soil of agroecosystems of such medicinal plants: Mentha piperita, Inula helenium, Thymus serpillum, Rosa odorata and Calendula officinalis. A total of 106 isolates from soil of medicinal plants were examined for resistance to 9 antibiotics: lincomycin, oleandomycin, ampicillin, cefepime, ciprofloxacin, vancomycin, gentamicin, streptomicin, cefamandole. From all the above-mentioned ecosystems, antibioticresistant pathogenic microorganisms have been isolated. From soil with cultivated Thymus serpillum two bacterial strains: Serratia marcescens and Yersinia enterocolitica were resistant to majority of tested antibiotics. From the soil samples with cultivated Inula helenium 15 dominant bacterial strains were isolated. Pantoea agglomerans was one of the most antibiotics resistant bacteria among of others tested. Serratia odorifera biogroup 1 isolated from agroecosystem of Mentha piperita, was resistant to vancomycin, lincomycin, ampicillin and to cefepime. High level of antibiotic resistance was detected for Enterococcus faecalis and Bacillus cereus isolated from agroecosystems of Calendula officinalis and Rosa odorata were organic manure was used. The soil of agroecosystems, where medicinal plants are cultivated, is a source of antibioticresistant microorganisms pathogenic and conditionally pathogenic for humans. [ABSTRACT FROM AUTHOR]

The survival of enteric pathogens in sewage sludge can lead to their transferral into the soil environment and subsequent contamination of crops and water courses. This, in turn, can increase the potential spread of gastrointestinal disease. This work aims to determine the persistence of several microorganisms, co‐introduced with sewage sludge, when exposed to varying proportions of sewage sludge to soil. Three microcosm‐based studies are established, inoculated with Salmonella Dublin or an environmentally persistent strain of Escherichia coli (quantified periodically over a period of 42 days), or indigenous sewage sludge E. coli (quantified over a period of 56 days). Treatments consist of a mixture containing: 0, 15, 25, 50, 75, and 100% soil or sludge, depending upon the experiment. Each introduced microorganism decline significantly over time, with greater quantities of soil generally instigating greater die‐off particularly in the cases of environmentally persistent E. coli and S. Dublin. However, this relationship is not proportionally related as sludge/soil mixtures show greater declines than pure soil treatments. In contrast, indigenous sewage sludge E. coli has a more consistent decline across all treatments. This indicates that indigenous strains are more resilient and can be indicative of natural behavior. Moreover, the effects of soil‐borne factors on pathogen attenuation are context dependent and non‐linear, possibly arising from the relative spatial distribution of introduced sludge and attendant microbes in soil. [ABSTRACT FROM AUTHOR]

Phytophthora cinnamomi is one of the most important plant pathogens in the world, causing root rot in more than a thousand plant species. This observational study was carried out on a P. cinnamomi infected heathland of Erica umbellata used as goat pasture. The patterns and shapes of disease foci and their distribution were described in a spatial and temporal context using an aerial photograph record. A set of topographic traits was selected on the basis of a disease dynamic hypothesis and their effects on observed spatial disease patterns were analyzed. Incipient infections situated in flat terrain expanded as compact circular front patterns with a low growth rate. On slopes, disease patches developed more rapidly down slope, forming parabolic shapes. The axis direction of the parabolas was highly correlated with terrain aspect, while the parabolic amplitude was associated with land curvature and slope. New secondary foci appeared over the years producing an accelerated increase of the affected surface. These new foci were observed in sites where disease density was higher or near sites more frequently visited by animals such as the stable or the forage crop. In contrast, a smaller number of disease foci occur in areas which animals are reluctant to visit, such as where they have a short range of vision. Our results suggest that 1) the growth of existing P. cinnamomi foci is controlled by a combination of root-to-root contact and water flows, 2) the increase in the diseased area arises mainly from the multiplication of patches, 3) the formation of new foci is mediated by long-distance transport due to the movement of animals and humans along certain preferential pathways, and 4) geomorphology and topography traits are associated with the epidemiology of this soil-borne pathogen. [ABSTRACT FROM AUTHOR]

Early detection of soil-borne pathogens, which have a negative effect on almost all agricultural crops, is crucial for effective targeting with the most suitable antifungal agents and thus preventing and/or reducing their severity. They are responsible for severe diseases in various plants, leading in many cases to substantial economic losses. In this study, infrared (IR) spectroscopic method, which is known as sensitive, accurate and rapid, was used to discriminate between different fungi in a mixture was evaluated. Mixed and pure samples of Colletotrichum , Verticillium , Rhizoctonia , and Fusarium genera were measured using IR microscopy. Our spectral results showed that the best differentiation between pure and mixed fungi was obtained in the 675–1800 cm −1 wavenumber region. Principal components analysis (PCA), followed by linear discriminant analysis (LDA) as a linear classifier, was performed on the spectra of the measured classes. Our results showed that it is possible to differentiate between mixed-calculated categories of phytopathogens with high success rates (~100%) when the mixing percentage range is narrow (40–60) in the genus level; when the mixing percentage range is wide (10–90), the success rate exceeded 85%. Also, in the measured mixed categories of phytopathogens it is possible to differentiate between the different categories with ~100% success rate. [ABSTRACT FROM AUTHOR]

Pseudomonas fluorescens 2P24 produces 2,4-diacetylphloroglucinol (2,4-DAPG) as the major antibiotic compound that protects plants from soil-borne diseases. Expression of the 2,4-DAPG biosynthesis enzymes, which are encoded by the phlACBD locus, is under the control of a delicate regulatory network. In this study, we identified a novel role for the outer membrane protein gene oprF , in negatively regulating the 2,4-DAPG production by using random mini-Tn5 mutagentsis. A sigma factor gene sigX was located immediately upstream of the oprF gene and shown to be a positive regulator for oprF transcription and 2,4-DAPG production. Genetic analysis of an oprF and sigX double-mutant indicated that the 2,4-DAPG regulation by oprF was dependent on SigX. The sigX gene did not affect PhlA and PhlD expression, but positively regulated the level of malonyl-CoA, the substrate of 2,4-DAPG synthesis, by influencing the expression of acetyl-CoA carboxylases. Further investigations revealed that sigX transcription was induced under conditions of salt starvation or glycine addition. All these findings indicate that SigX is a novel regulator of substrate supplements for 2,4-DAPG production. [ABSTRACT FROM AUTHOR]

Understanding the contribution of seed tuber- and soilborne inocula of Rhizoctonia solani AG 3-PT in causing potato disease epidemics is an important step in implementing effective management strategies for the pathogen. A 2-year study was conducted to evaluate the contribution of each source of inoculum using an integrative experimental approach combining field trials and molecular techniques. Two distinct sets of genetically marked isolates were used as seed tuberbome and soilborne inocula in a mark-release-recapture experiment. Disease assessments were done during tuber initiation and at tuber harvest. Both inoculum sources were found to be equally important in causing black scurf disease, whereas soilborne inocula appealed to be more important for root and stolon infection, and seedborne inocula contributed more to stem canker. However, seed tuber-transmitted genotypes accounted for 60% of the total recovered isolates when genotyped using three polymerase chain reaction resUiction fragment length polymorphism markers. The changes in population structure of the experimental R. solani population over the course of the growing season and across two growing seasons were investigated using eight microsatellite markers. The populations at different sampling times were somewhat genetically differentiated, as indicated by Nei's gene diversity (0.24 to 0.27) and the fixation index (FST) The proportion of isolates with genotypes that differed from the inoculants ranged from 13 to 16% in 2013 and 2014, respectively, suggesting the possibility of emergence of new genotypes in the field. Because both soilborne and tuberborne inocula are critical, it is important to ensure the use of pathogen-free seed tubers to eliminate seed tuberborne inoculum and the introduction of new genotypes of R. solani for sustainable potato production in South Africa. [ABSTRACT FROM AUTHOR]

Reuse of olivemill wastewaters (OMWWs) in agriculture represents a significant challenge for health and safety of our planet. Phytotoxic compounds in OMWW generally prohibit use of untreated OMWWs for agricultural irrigation or direct discharge into surface waters. However, pretreated OMWW can have positive effects on chemical and microbiological soil characteristics, to fight against fungal soil-borne pathogens. Low amounts of OMWW following thermal (TT-OMWW) and high-pressure homogenization (HPH-OMWW) pretreatments counteracted growth of some of 12 soil-borne and/or pathogenic fungi examined. With fungal growth measured as standardized change in time to half maximum colony diameter, 1τ, overall, HPH-OMWW showed increased bioactivity, as increased mean 1τ from 3.0 to 4.8 days. Principal component analysis highlighted two fungal groups: Colletotrichum gloeosporioides, Alternaria alternata, Sclerotium rolfsii, and Rosellinia necatrix, with growth strongly inhibited by the treated OMWWs; and Aspergillus ochraceus and Phaeoacremonium parasiticum, with stimulated growth by the treated OMWWs. As a non-thermal treatment, HPH-OMWW generally shows improved positive effects, which potentially arise from preservation of the phenols. [ABSTRACT FROM AUTHOR]

Most crops are routinely protected against seed-born and soil-borne fungal pathogens through seed-applied fungicides. The recently released succinate dehydrogenase inhibitor (SDHI), sedaxane®, is a broad-spectrum fungicide, used particularly to control Rhizoctonia spp., but also has documented growth-enhancement effects on wheat. This study investigates the potential biostimulant effects of sedaxane and related physiological changes in disease-free maize seedlings (3-leaf stage) at increasing application doses (25, 75 and 150 mg a.i. seed-1) under controlled sterilized conditions. We show sedaxane to have significant auxin-like and gibberellin-like effects, which effect marked morphological and physiological changes according to an approximate saturation dose-response model. Maximum benefits were attained at the intermediate dose, which significantly increased root length (C60%), area (C45%) and forks (C51%), and reduced root diameter as compared to untreated controls. Sedaxane enhanced leaf and root glutamine synthetase (GS) activity resulting in greater protein accumulation, particularly in the above-ground compartment, while glutamate synthase (GOGAT) activity remained almost unchanged. Sedaxane also improved leaf phenylalanine ammonia-lyase (PAL) activity, which may be responsible for the increase in shoot antioxidant activity (phenolic acids), mainly represented by p-coumaric and caffeic acids. We conclude that, in addition to its protective effect, sedaxane can facilitate root establishment and intensify nitrogen and phenylpropanoid metabolism in young maize plants, and may be beneficial in overcoming biotic and abiotic stresses in early growth stages. [ABSTRACT FROM AUTHOR]

Fumigant methyl isothiocyanate (MITC) is a very promising alternative to methyl bromide, providing effective control of soil borne disease. However, there is a significant volatilization of MITC following fumigation because of its high application rates and high vapor pressure. Covering the soil surface with plastic tarps is a common approach used for restricting fumigant emissions to the atmosphere. To minimize atmospheric emissions of MITC by tarping, we determined the effect of temperature, humidity, and fumigant mixtures on the permeability to MITC of low density polyethylene film (LDPE) and totally impermeable film (TIF), using static sealed chambers. The results showed that temperature had the largest impact on the mass transfer coefficient (MTC) of MITC across LDPE film; the permeability increased 8.8 times when temperature was raised from 5 °C to 35 °C. There was a small increase in tarp permeability with increasing relative humidity below 75%, but it was little difference in MTC values between 75% and 100% relative humidity. The permeability of TIF to MITC is much lower than that of LDPE. TIF is much more sensitive to the ambient conditions; both temperature and humidity can drastically alter the MTC of MITC across TIF. Fumigant mixtures of MITC did not have a significant impact on the MTC across the LDPE film. The results of this study will contribute to establishing guidance on the appropriate environmental conditions for using tarping films to reduce MITC emission and achieve adequate pest control. [ABSTRACT FROM AUTHOR]

The recently proposed Microbiome Mutiny Hypothesis posits that members of the human microbiome obtain information about the host individuals' health status and, when host survival is compromised, switch to an intensive exploitation strategy to maximize residual transmission. In animals and humans, sepsis is an acute systemic reaction to microbes invading the normally sterile body compartments. When induced by formerly mutualistic or neutral microbes, possibly in response to declining host health, sepsis appears to fit the ‘microbiome mutiny’ scenario except for its apparent failure to enhance transmission of the causative organisms. We propose that the ability of certain species of the microbiome to induce sepsis is not a fortuitous side effect of within-host replication, but rather it might, in some cases, be the result of their adaptive evolution. Whenever host health declines, inducing sepsis can be adaptive for those members of the healthy human microbiome that are capable of colonizing the future cadaver and spread by cadaver-borne transmission. We hypothesize that such microbes might exhibit switches along the ‘mutualist – lethal pathogen – decomposer – mutualist again’ scenario, implicating a previously unsuspected, surprising level of phenotypic plasticity. This hypothesis predicts that those species of the healthy microbiome that are recurring causative agents of sepsis can participate in the decomposition of cadavers, and can be transmitted as soil-borne or water-borne infections. Furthermore, in individual sepsis cases, the same microbial clones that dominate the systemic infection that precipitates sepsis, should also be present in high concentration during decomposition following death: this prediction is testable by molecular fingerprinting in experimentally induced animal models. Sepsis is a leading cause of human death worldwide. If further research confirms that some cases of sepsis indeed involve the ‘mutiny’ (facultative phenotypic switching) of normal members of the microbiome, then new strategies could be devised to prevent or treat sepsis by interfering with this process. [ABSTRACT FROM AUTHOR]

Background: Soil-transmitted helminths (STHs) are widespread in underdeveloped countries. In Ethiopia, the prevalence and distribution of helminth infection varies by different exposing risk factors. We therefore investigated the prevalence of and risk factors of STHs infection in school children living in Ambo town, west Shoa Ethiopia.Methods: In 2014/15, among 375 school children planed to be included in this study, only 321 school children were recruited in the study. Data onto school children from different schools were collected, including stool samples for qualitative STHs analysis. Questionnaire data on various demographic, housing and lifestyle variables were also available.Results: Prevalence of any STHs infection was 12.6%. The respective prevalence of major soil-transmitted helminths is Ascaris (7.8%), Hookworm (2.8%) and Trichuris (2.2%). This study result shows STHs prevalence varies regards to age, sex, latrine use, family size and nail trimming.Conclusion: The results of the present study indicated that the percentage of positive finding for STHs in Ambo area is low. Besides, Large Family size, not nail trimming and unavailability of improved latrine were identified as predisposing factor for STHs infections. All school children enrolled and not enrolled in this study should be treated twice a year until the prevalence falls below the level of public health importance. [ABSTRACT FROM AUTHOR]

Phytophthora nicotianae and Ralstonia solanacearum are two of the most important pathogens affecting tobacco worldwide. Greater insight regarding genetic systems controlling resistance to these two soilborne pathogens, as well as identification of DNA markers associated with genomic regions controlling this resistance, could aid in variety development. An evaluation of 50 historical tobacco lines revealed a high positive correlation between resistances to the two pathogens, preliminarily suggesting that some genomic regions may confer resistance to both pathogens. A quantitative trait loci (QTL) mapping experiment designed to investigate the genetic control of soilborne disease resistance of highly resistant 'K346' tobacco identified four QTL significantly associated with resistance to P. nicotianae (explaining 60.0% of the observed phenotypic variation) and three QTL to be associated with R. solanacearum resistance (explaining 50.3% of the observed variation). The two QTL with the largest effect on Phytophthora resistance were also found to be the QTL with the greatest effects on resistance to Ralstonia. This finding partially explains previously observed associations between resistances to these two pathogens among U.S. current cultivars and within breeding populations. Further study is needed to determine whether these relationships are due to the same genes (i.e., pleiotropy) or favorable coupling-phase linkages that have been established over time. [ABSTRACT FROM AUTHOR]

There is increasing evidence showing that microbes can influence plant-insect interactions. In addition, various studies have shown that aboveground pathogens can alter the interactions between plants and insects. However, little is known about the role of soil-borne pathogens in plant-insect interactions. It is also not known how environmental conditions, that steer the performance of soil-borne pathogens, might influence these microbe-plant-insect interactions. Here, we studied effects of the soil-borne pathogen Rhizoctonia solani on aphids (Sitobion avenae) using wheat (Triticum aestivum) as a host. In a greenhouse experiment, we tested how different levels of soil organic matter (SOM) and fertilizer addition influence the interactions between plants and aphids. To examine the influence of the existing soil microbiome on the pathogen effects, we used both unsterilized field soil and sterilized field soil. In unsterilized soil with low SOM content, R. solani addition had a negative effect on aphid biomass, whereas it enhanced aphid biomass in soil with high SOM content. In sterilized soil, however, aphid biomass was enhanced by R. solani addition and by high SOM content. Plant biomass was enhanced by fertilizer addition, but only when SOM content was low, or in the absence of R. solani. We conclude that belowground pathogens influence aphid performance and that the effect of soil pathogens on aphids can be more positive in the absence of a soil microbiome. This implies that experiments studying the effect of pathogens under sterile conditions might not represent realistic interactions. Moreover, pathogen-plant-aphid interactions can be more positive for aphids under high SOM conditions. We recommend that soil conditions should be taken into account in the study of microbe-plant-insect interactions. [ABSTRACT FROM AUTHOR]

Objectives. To investigate if work activities, dust exposure, and protection measures were associated with a 2011 to 2014 coccidioidomycosis outbreak among workers constructing 2 solar farms in California. Methods. In 2013, wemailed self-administered questionnaires to employees who were onsite at the solar farms where the outbreak occurred to identify cases of clinical coccidioidomycosis and compare with asymptomatic workers by using multivariate logistic regression. Results. When we compared 89 workers with clinical coccidioidomycosis to 325 asymptomatic workers, frequently being in a dust cloud or storm (odds ratio [OR] = 5.93; 95% confidence interval [CI] = 3.18, 11.06) significantly increased the odds of clinical coccidioidomycosis, whereas frequently wetting soil before soil-disturbing activity (OR = 0.42; 95% CI = 0.24, 0.75) was protective. When we controlled for being in a dust cloud or storm, frequent soil disturbance significantly increased the odds of clinical coccidioidomycosis only among those who reported wearing a respirator infrequently (OR = 2.31; 95% CI = 1.27, 4.21). Conclusions. Utilization of personal and employer-driven safety practices and increased coccidioidomycosis awareness among construction workers should be considered during the planning of any construction work in coccidioidomycosis-endemic regions to prevent occupational infections and outbreaks. [ABSTRACT FROM AUTHOR]

The soil-borne fungus Verticillium causes serious vascular disease in a wide variety of annual crops and woody perennials. Verticillium wilt is notoriously difficult to control by conventional methods, so there is great potential for biocontrol to manage this disease. In this study we aimed to review the research about Verticillium biocontrol to get a better understanding of characteristics that are desirable in a biocontrol agent (BCA) against Verticillium wilt. We only considered studies in which the BCAs were tested on plants. Most biocontrol studies were focused on plants of the Solanaceae, Malvaceae, and Brassicaceae and within these families eggplant, cotton, and oilseed rape were the most studied crops. The list of bacterial BCAs with potential against Verticillium was dominated by endophytic Bacillus and Pseudomonas isolates, while non-pathogenic xylem-colonizing Verticilliumand Fusariumisolates topped the fungal list. Predominant modes of action involved in biocontrol were inhibition of primary inoculum germination, plant growth promotion, competition and induced resistance. Many BCAs showed in vitro antibiosis and mycoparasitism but these traits were not correlated with activity in vivo and there is no evidence that they play a role in planta. Good BCAs were obtained from soils suppressive to Verticillium wilt, disease suppressive composts, and healthy plants in infested fields. Desirable characteristics in a BCA against Verticillium are the ability to (1) affect the survival or germination of microsclerotia, (2) colonize the xylem and/or cortex and compete with the pathogen for nutrients and/or space, (3) induce resistance responses in the plant and/or (4) promote plant growth. Potential BCAs should be screened in conditions that resemble the field situation to increase the chance of successful use in practice. Furthermore, issues such as large scale production, formulation, preservation conditions, shelf life, and applicationmethods should be considered early in the process of selecting BCAs against Verticillium. [ABSTRACT FROM AUTHOR]

Biocontrol using beneficial antagonists to limit soil-borne disease is a promising approach. It can reduce the use of chemical pesticides and protect the environment. This study investigated the effects of three soil environmental factors on Paenibacillus polymyxa L1-9 colonization by antibiotic label method. The results showed that L1-9 strain of the root soil and cucumber tissues in pH 6, pH 7 and pH 8 treatments had similar variation trends and pH 7 soil had the greatest number of L1-9 strain. The L1-9 number could maintain greater number over a longer period at 25 °C than at other temperatures (15 °C, 20 °C and 30 °C). When soil organic matter content was below 60 g kg-1, higher organic matter content increased L1-9 numbers, and improved colonization ability, however, the L1-9 numbers and colonization ability were significantly decreased under 80 g kg-1 organic matter content. The results indicated that the biocontrol agent L1-9 could play a better effect at the soil initial pH 7, soil temperatures 25 °C and 60 g kg-1 soil organic matter content. It will provide references for the application of the biocontrol agent L1-9 in agricultural production. [ABSTRACT FROM AUTHOR]

Background and aims: Anaerobic Soil Disinfestation (ASD) is a chemical-independent approach to managing soilborne phytopathogens. While it has been demonstrated that ASD can suppress phytopathogens in vegetable cropping systems, it has not been examined for control of tree-crop diseases under nursery conditions. Here we report on the potential of using ASD to manage soilborne populations of Agrobacterium tumefaciens and Pythium ultimum under walnut rootstock nursery conditions and compared the efficacy of ASD with the chemical fumigant Telone-C35. Methods: Mesh bags of sterile field soil inoculated with either A. tumefaciens or P. ultimum were buried in the first of two trials at 7.6 and 15.2 cm soil depths and in the second trial at 15.2, 45.7, and 76.2 cm soil depths prior to ASD or fumigation treatments. Populations of A. tumefaciens and P. ultimum in the mesh bags were determined immediately after ASD treatment. Bacterial rRNA was extracted from bulk soils at these depths prior, immediately following ASD, and 4 months post-ASD to determine the effect of ASD on the bacterial community composition. Results and conclusions: After seven days of ASD treatment, populations of both phytopathogens fell below detection limits at 7.6 and 15.2 cm soil depths. After completion of the six-week ASD treatment or 4-week fumigation period, populations of A. tumefaciens remained below detection limits at 7.6 and 15.2 cm depths and were not significantly different from A. tumefaciens population levels detected in the fumigation treatment. Futhermore, A. tumefaciens populations were significantly reduced, compared to no-treatment control soils, in both ASD and fumigation treatments at the 45.7 and 76.2 cm depths. Pythium ultimum populations dipped below detection limits after ASD treatment at 7.6 and 15.2 cm soil depths, and were significantly lower than no-treatment controls at the 45.7 cm depth. The bacterial community composition of ASD-treated soils also differed significantly as a function of soil depth, and the effect of ASD on the bacterial community composition persisted over time. The documented ASD-induced changes in the soilborne bacterial communities may have contributed to the population reductions observed for both A. tumefaciens and P. ultimum. The significant reductions of A. tumefaciens and P. ultimum, down to a depth of 76.2 cm, were similar for both ASD and Telone C-35 treated soils. This illustrates the potential of ASD to replace chemical fumigants as a management tool for key phytopathogenic agents. [ABSTRACT FROM AUTHOR]

The understanding of the dynamic of soil-borne diseases is related to the microbial composition of the rhizosphere which is the key to progress in the field of biological control. Trichoderma spp. is commonly used as a biological control agent. The use of next generation sequencing approaches and quantitative PCR are two successful approaches to assess the effect of using compost as substrate fortified with two Trichoderma strains (Trichoderma harzianum or Trichoderma asperellum) on bacterial and fungal communities in pepper rhizosphere infected with Phytophthora nicotianae. The results showed changes in the bacterial rhizosphere community not attributed to the Trichoderma strain, but to the pathogen infection, while, fungi were not affected by pathogen infection and depended on the type of substrate. The Trichoderma asperellum fortified compost was the most effective combination against the pathogen. This could indicate that the effect of fortified composts is greater than compost itself and the biocontrol effect should be attributed to the Trichoderma strains rather than the compost microbiota, although some microorganisms could help with the biocontrol effect. [ABSTRACT FROM AUTHOR]

A rotation trial spanning nine consecutive growing seasons was established in 2004 to study cumulative effects of specific onion- and potato-focused crop rotations on soil nutrient levels, soil biological communities, plant productivity and soilborne diseases. Soil microbial activity, as determined by fluorescein diacetate hydrolysis, was greatest in the ‘sustainable’ potato rotation in five of the 6 years that the test was carried out.Rhizoctonia solanianastomosis group 3 DNA was first detected in potato monoculture soils in the fifth year, with numbers increasing from then on, but was not detected in the onion monoculture throughout the trial period. Potato yields were greater when a crop other than potato was grown in the previous year compared with when potatoes were the preceding crop. After 2005, mean annual onion yields from the onion monoculture were less than yields from the other rotations. Black scurf on potato tubers was the primary soilborne disease observed during the study, and the incidence of this disease was greater in the potato monoculture than the other rotations after the second year, and least when potatoes had not been grown in the same ground the three previous seasons. This long-term crop rotation study has demonstrated the benefits of a ‘sustainable’ rotation where potatoes or onions were grown every fourth growing season, with different crops (oat, broccoli, cabbage, squash) grown in the intervening years, compared with the conventional consecutive biennial crops of potato and onion. [ABSTRACT FROM PUBLISHER]

The soil-borne necrotrophic pathogen fungus Rhizoctonia solani is destructive, causing disease in various important crops. To date, little is known about the host defence mechanism in response to invasion of R. solani . Here, an iTRAQ-based proteomic analysis was employed to investigate pathogen-responsive proteins in the disease tolerant/resistant cotton cultivar CRI35. A total of 174 differentially accumulated proteins (DAPs) were identified after inoculation of cotton plants with R. solani . Functional categorization analysis indicated that these DAPs can be divided into 12 subclasses. Notably, a large portion of DAPs are known to function in reactive oxygen species (ROS) metabolism and the expression of several histone-modifying and DNA methylating proteins were significantly induced upon challenge with the fungus, indicating that the redox homeostasis and epigenetic regulation are important for cotton defence against the pathogen. Additionally, the expression of proteins involved in phenylpropanoid biosynthesis was markedly changed in response to pathogen invasion, which may reflect a particular contribution of secondary metabolism in protection against the fungal attack in cotton. Together, our results indicate that the defence response of cotton plants to R. solani infection is active and multifaceted and involves the induction of proteins from various innate immunity-related pathways. Significance Cotton damping-off is a destructive disease caused by the necrotrophic fungus Rhizoctonia solani . To date, the host defence mechanism involved in the disease protection remains largely unknown. Here, we reported the first proteomic analysis on cotton immune responses against R. solani infection. Employing iTRAQ technique, we obtained a total of 174 differentially accumulated proteins (DAPs) that can be classified into 12 functional groups. Further analysis indicated that ROS homeostasis, epigenetic regulation and phenylpropanoid biosynthesis were tightly associated with the innate immune responses against R. solani infection in cotton. The obtained data provide not only important information for understanding the molecular mechanism involved in plant- R. solani interaction but also application clues for genetic breeding of crops with improved R. solani resistance. [ABSTRACT FROM AUTHOR]

Biochar (BC) is increasingly applied in agriculture; however, due to its adsorption and degradation properties, biochar may also affect the efficacy of fumigant in amended soil. Our research is intended to study the effects of two types of biochars (BC-1 and BC-2) on the efficacy and emission of methyl isothiocyanate (MITC) in biochar amendment soil. Both types of biochars can significantly reduce MITC emission losses, but, at the same time, decrease the concentration of MITC in the soil. The efficacy of MITC for controlling soil-borne pests (Meloidogyne spp., Fusarium spp. Phytophthora spp., Abutilon theophrasti and Digitaria sanguinalis) was reduced when the biochar (BC-1 and BC-2) was applied at a rate of higher than 1% and 0.5% (on a weight basis) (on a weight basis), respectively. However, increased doses of dazomet (DZ) were able to offset decreases in the efficacy of MITC in soils amended with biochars. Biochars with strong adsorption capacity (such as BC-1) substantially reduced MITC degradation rate by 6.2 times, and increased by 4.1 times following amendment with biochar with high degradability (e.g., BC-2), compared to soil without biochar amendment. This is due to the adsorption and degradation of biochar that reduces MITC emission losses and pest control. [ABSTRACT FROM AUTHOR]