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Plants produce reactive oxygen species (ROS) to defend pathogens. To counteract this attack, certain pathogens express superoxide dismutases (SODs) to scavenge host-derived ROS. However, the roles of SODs in Verticillium dahliae, an important vascular pathogen, are not clear. Our previous study has shown that a putative extracellular SOD (VdSOD5) of V. dahliae is significantly induced by culturing in cotton tissues, suggesting that VdSOD5 may play an important role in host–pathogen interactions and virulence. Here, we showed that VdSOD5 encoded a superoxide dismutase with a cofactor copper-binding site and a functional signal peptide that can conduct protein secretion in an invertase-mutated yeast strain. The mutations in VdSOD5 (ΔVdSOD5) did not change the normal vegetative growth and conidial production but reduced the virulence of V. dahliae on susceptible host cotton. Further studies showed that the transcription of VdSOD5 was significantly up-regulated during the early stage of infection, and the loss-of-function of VdSOD5 decreased culture filtrate and fungal tissue SOD activities of V. dahliae by 74 and 28%, respectively. Compared to the wild-type strain Vd991, the ΔVdSOD5 showed the same sensitivity to the intracellular ROS generator menadione. Furthermore, nitroblue tetrazolium (NBT) staining demonstrated that VdSOD5 functioned in the detoxification of superoxides generated by host roots during infection. These results suggest that VdSOD5 of V. dahliae is an important virulence factor, secreted out of cells to combat host-derived ROS.

Potato is the largest non-cereal food crop worldwide and ranked as the world's fourth most important food crop after rice, wheat, and maize. Potato is a vital food-security crop and substitute for cereal crop considering its high yield and great nutritive value. Therefore, by replacing wheat, rice or maize in traditional staple foods partly by potato, the nutritional value of traditional foods and the utilization of potato are expected to be improved. China is the largest potato producer worldwide in terms of either volume or area. However, majority of potatoes are consumed as fresh vegetables for cuisine, and the industrial processing rate is much lower than the global average. Thus, research and development for nutritional potato stable food suitable for the dietary habits of Chinese residents are of great significance. However, we still confronted plenty of constraints in the development of potato staple food. In order to develop potato staple food suitable for Chinese residents' dietary habit like noodles, Mantou (steamed bread), rice and rice noodles, also to industrialize production of potato staple foods, some transformations need to be realized. Independent innovation is the only choice to realize the potato staple food processing and industrial development strategy on the technical level. Thus a lot of researches have been done to promote the development of potato staple food in China. Up to now, we already developed a series kinds of potato staple foods and some of these staple foods have already been widely promoted in Chinese markets.

Mycotoxin contamination in agro-food systems has been a serious concern globally during the last few decades. Mycotoxins are toxic secondary metabolites produced by fungi when they grow in agro-food products and feedstuff. Several detection techniques have been developed in recent years to detect mycotoxins in the food and feed effectively. HPLC based techniques are very common in usage in the laboratories for the testing of mycotoxins. In recent years, immuno-based assays is widely used and have been reported at large due to its sensitivity and limited detection time. Immuno assay-based kits were developed effectively to be used in the fields and in storage systems to detect the mycotoxin levels. Microarray-based immunoassays developed in the recent years could simultaneously detect aflatoxin, ochratoxin, and zearalenone with the higher sensitivity. Aptamer-based assays could target the detection of ochratoxin and aflatoxins and fumonisins at high specificity in food products. In recent years, several assays reported for the simultaneous multiple detection of different mycotoxin was based on HPLC and LC-MS/MS. There is a need for the use of these advanced technologies in the commercial scale.