Research on Pathogenic Fungi and Mycotoxins in China

Researchers have made great progress in the mechanism of mycotoxins biosynthesis, pathogenicity, and the construction of detection methods. This collection holds fundamental and applied research on pathogenic fungi and mycotoxins in China, which directly or indirectly affect the health of plants, animals, and humans. Some papers mainly study the mechanism of mycotoxin biosynthesis, including the crucial genes, environmental factors, and regulation mechanisms, which is beneficial to advancing our knowledge of this area. Some papers focus on the toxicity of mycotoxins, which is helpful to the detoxification of mycotoxins and the reduction of the hazardous effect of mycotoxins. Special attention is given to the leading detection methods, especially on-site rapid detection. These effective and feasible methods are important for discovering and controlling the risk of mycotoxins

Sensors and biosensors for pathogen and pest detection in agricultural systems : recent trends and oportunities

Pathogen and pest-linked diseases across agriculture and ecosystems are a major issue towards enhancing current thresholds in terms of farming yields and food security. Recent developments in nanotechnology allowed the designing of new generation sensors and biosensors in order to detect and mitigate these biological hazards. However, there are still important challenges concerning its respective applications in agricultural systems, typically related to point-of-care testing, cost reduction and real-time analysis. Thus, an important question arises: what are the current state-of-the-art trends and relationships among sensors and biosensors for pathogen and pest detection in agricultural systems? Targeted to meet this gap, a comparative study is performed by a literature review of the past decade and further data mining analysis. With the majority of the results coming from recent studies, leading trends towards new technologies were reviewed and identified, along with its respective agricultural application and target pathogens, such as bacteria, viruses, fungi, as well as pests like insects and parasites. Results have indicated lateral flow assay, lab-on-a-chip technologies and infrared thermography (both fixed and aerial) as the most promising categories related to sensors and biosensors driven to the detection of several different pathogenic varieties. The main existing interrelations between the results are especially associated to cereals, fruits and nuts, meat and dairy along with vegetables and legumes, mostly caused by bacterial and fungal infections. Additional results also presented and discussed, providing a fertile groundwork for decision-making and further developments in modern smart farming and IoT-based agriculture

Multi-sensor and data fusion approach for determining yield limiting factors and for in-situ measurement of yellow rust and fusarium head blight in cereals

The world’s population is increasing and along with it, the demand for food. A novel parametric model (Volterra Non-linear Regressive with eXogenous inputs (VNRX)) is introduced for quantifying influences of individual and multiple soil properties on crop yield and normalised difference vegetation Index. The performance was compared to a random forest method over two consecutive years, with the best results of 55.6% and 52%, respectively. The VNRX was then implemented using high sampling resolution soil data collected with an on-line visible and near infrared (vis-NIR) spectroscopy sensor predicting yield variation of 23.21%. A hyperspectral imager coupled with partial least squares regression was successfully applied in the detection of fusarium head blight and yellow rust infection in winter wheat and barley canopies, under laboratory and on-line measurement conditions. Maps of the two diseases were developed for four fields. Spectral indices of the standard deviation between 500 to 650 nm, and the squared difference between 650 and 700 nm, were found to be useful in differentiating between the two diseases, in the two crops, under variable water stress. The optimisation of the hyperspectral imager for field measurement was based on signal-to-noise ratio, and considered; camera angle and distance, integration time, and light source angle and distance from the crop canopy. The study summarises in the proposal of a new method of disease management through suggested selective harvest and fungicide applications, for winter wheat and barley which theoretically reduced fungicide rate by an average of 24% and offers a combined saving of the two methods of £83 per hectare

The application of Near Infrared Transmittance (NIT) individual kernel sorting technology to improve grain quality from spring and durum wheat infected with Fusarium and the effects on broiler chicken performance and immune response.

This project investigated the use of new near infrared transmittance (NIT) technology for individual kernel sorting to reduce Fusarium damaged kernels (FDK) and mycotoxins in grain. There were two objectives: 1) determine the efficiency of sorting; and 2) assess how highly contaminated sorted grain fractions can be used in dietary challenges for broilers as a screen for methods to reduce mycotoxin exposure. Fusarium damaged kernels are associated with lower crude protein (CP) caused by fungal infestation during kernel development, and may contain varying concentrations of mycotoxins (e.g. deoxynivalenol; DON). The BoMill TriQ measures the NIT of limited spectra to predict CP variation among individual kernels at ~2 - 3 MT/hour. Five sources of downgraded grain attained from grain producers in Western Canada in 2013 were sorted into ten calibration fractions, each analyzed for CP, FDK and 16 common mycotoxins. From these analyses, three wheat sources were individually sorted into three test fractions: outliers (10%); high FDK (low CP; 20% of source); and low FDK (high CP; 70% of source). Four diet recombinations were produced based on increasing inclusion of the high % FDK fraction [0% (M0), 20% (M20), 40% (M40) or 60% (M60)] of each wheat source, providing increasing mycotoxin concentrations in the test diets. Productions of these diets from re-combining the FDK fractions enabled a 3 wheat source x 4 FDK level (M0, M20, M40, M60) factorial design. The 12 test diets were included at 70 (starter, 0 - 21 d) and 75% (grow/finisher, 21 - 35 d) of a basal diet. Diets were formulated to meet or exceed NRC (1994) requirements for broilers. Eight cages of five, one-day old male Ross 308 broilers were each randomly assigned to the 12 starter diets. The number of cages were reduced to three per diet at 21 d. Broiler performance were recorded for the 0 - 21 and 21 - 35 d. Apparent metabolizable energy (AME; kcal ME/kg diet) and nitrogen retention (NR; %) were determined using digestible markers and excreta collections. Five biomarkers of immune function were measured for starter and grower/finisher periods: 1) cell-mediated immune response to injection of the T cell mitogen phytohemagglutinin (PHA); 2) humoral response to immunization with bovine serum albumin (BSA) antigen; 3) relative weights of liver, spleen and bursa of Fabricius; 4) heterophil to lymphocyte (H:L) ratio; and 5) histopathology of primary and secondary immune organs. Analysis of sorting efficiency of this technology indicated that grain could be separated into 10% increments based on unique spectral ranges and their correlation to the chemical characteristics of CP. Indications were that the lowest 20% CP kernels contained increased FDK (15.4%) and DON (10.2 ppm) compared to the unsorted kernels (2.4% and 1.7 ppm). The statistical correlations between FDK, DON and CP provided the capability to produce high and low mycotoxin fractions for use in the poultry feeding trial. Analysis of growth and performance endpoints of each exposure period indicated no significant difference (P > 0.05), however AME and NR were different (P 0.05) among treatment groups in cell-mediated (PHA; 0.32 - 0.35 % change), humoral (BSA; 0.57 - 0.64 % change) or H:L ratio (0.03 - 0.13 % change) immune responses. However, histopathological examination of the spleen (P < 0.05) at 21 d and the liver (P < 0.01) at 35 d showed increases in lymphoid aggregates and/or granulopoisis in the diet containing 8 ppm DON suggesting potential adverse effects on the immune system. Overall, the results of these studies indicate that the NIT technology has the potential to produce naturally contaminated diets with various levels of mycotoxins from a single source of grain. These naturally contaminated diets may improve our ability to evaluate models to examine the effects of mycotoxin exposures to poultry or livestock