Sensitivity of Botrytis cinerea from Vineyards to Boscalid, Isofetamid, and Pydiflumetofen in Shandong Province, China.

Succinate dehydrogenase inhibitor (SDHI) fungicides are the most commonly and effectively used class of fungicides for controlling gray mold. Among them, only boscalid has been registered in China for controlling grape gray mold, whereas isofetamid and pydiflumetofen are two new SDHI fungicides that have demonstrated high efficacy against various fungal diseases. However, the sensitivity of Botrytis cinerea isolates from vineyards in China to these three fungicides is currently unknown. In this study, the sensitivity of 55 B. cinerea isolates from vineyards to boscalid, isofetamid, and pydiflumetofen was determined, with the effective concentrations for inhibiting 50% of spore germination (EC50) values ranging from 1.10 to 393, 0.0300 to 42.0, and 0.0990 to 25.5 µg ml-1, respectively. The resistance frequencies for boscalid, isofetamid, and pydiflumetofen were 60.0, 7.2, and 12.8%, respectively. Three mutations (H272R, H272Y, and P225F) were detected in the SdhB subunit, with H272R being the most prevalent (75.7%), followed by H272Y (16.2%) and P225F (8.1%). All three mutations are associated with resistance to boscalid, and of them, H272R mutants exhibited high resistance. Only P225F and H272Y mutants exhibited resistance to isofetamid and pydiflumetofen, respectively. A weakly positive cross-resistance relationship was observed between boscalid and pydiflumetofen (r = 0.38, P < 0.05). Additionally, the H272R mutants showed no significant fitness costs, whereas the remaining mutants exhibited reduced mycelial growth (P225F) and sporulation (H272Y and P225F). These results suggest that isofetamid and pydiflumetofen are effective fungicides against B. cinerea in vineyards, but appropriate rotation strategies must be implemented to reduce the selection of existing SDHI-resistant isolates.

TaqMan-MGB PCR Method for Rapid Detection of QoI Fungicide Resistance in Chinese Populations of Plasmopara viticola.

Grape downy mildew caused by Plasmopara viticola is one of the most devastating diseases of grapevine worldwide. Quinone outside inhibitor (QoI) fungicides are commonly used for the control of the pathogen in grape fields across China. However, their recurrent use could lead to the emergence of resistance against these compounds. Based on the most common mutation in resistant isolates, a glycine to alanine substitution at amino acid position 143 (G143A) in the cytochrome b protein, a TaqMan-MGB PCR was developed for the rapid detection of resistance to the QoI fungicide azoxystrobin in P. viticola. Specificity and sensitivity of this method showed it could specifically detect the point mutations linked with QoI resistance in P. viticola, and the detection limit was 0.2 pg. It could also quantify the resistance allele even in isolate mixtures containing as little as 5% QoI-resistant P. viticola strains. With this method, a large P. viticola population (n = 2,373) was screened, and QoI-resistant isolates were identified for the first time in China. The average frequencies of the resistant genotype from eight major-grapevine regions were up to 66%. Taken together, the results not only provide a novel tool for the rapid distinction and quantification of the QoI-resistant allele in P. viticola but also provide important references for fungicide selection and application, which will facilitate resistance management of grape downy mildew and improve grape production systems in Chinese vineyards.

Study on Regenerative Processing Performance of Chlorinated Polyethylene Based on Wireless Network and Artificial Intelligence Technology.

The development of Information Technology has intruded the chemical industry. In the conventional chemical industry, humans are involved in monitoring the chemical evaporation processes. If there is any damage, then humans suffer enormously. These drawbacks are overcome in the chemical industry by implanting the sensors to the required blocks for monitoring the levels of chemical substances. An alert system can be introduced with an artificial intelligence algorithm to regenerate the process using details updated in the database. In this research, the machine-based Time-Temperature Superposition (TTS) method is implemented to monitor the chemical reactions in the chemical component manufacturing company.

[Analysis of volatile compounds of Salix babylonica by GC-MS].

OBJECTIVE: To study the volatile compounds of Salix babylonica, and to provide scientific basis for efficacy of attracting natural enemies and medicinal value of Salix babylonica. METHODS: The volatile compounds were collected from Salix babylonica by dy- namic headspace absorption method, and analyzed by gas chromatography-mass spectrum( GC-MS). RESULTS: Forty-one volatile com- pounds were identified from Salix babylonica. Intact plant of Salix babylonica had thirty-three kinds of volatile compounds and aphid-in- fested plant of Salix babylonica had thirty-eight kinds of volatile compounds. The volatile components of intact plant and aphid-infested plant had significant differences in the composition and proportion. Among them,the volatile components of aphid-infested plant added six kinds of vinyl materials,one kind of aldehyde and one kind of ketone. CONCLUSION: Adding volatile components,which included vinyl materials,aldehydes and ketones,might have the efficacy of attracting natural enemies. The volatile components might play an important role in the ecological protection for Salix babylonica. The functional components from the volatile compounds had good medicinal value, which are worthy of further research.

[Analysis of volatile compounds of fresh tea leaves from yaoluoping nature preserve by SDE-GC-MS].

OBJECTIVE: To study the volatile compounds of fresh tea leaves from Yaoluoping Nature Preserve, and to provide scientific basis for the quality and medicinal value of tea from high mountainous area. METHODS: The volatile compounds were extracted from fresh tea leaves by simultaneous distillation and extraction, and analyzed by gas chromatography-mass spectrum (GC-MS). RESULTS: 41 volatile compounds were identified from two tea cultivars, Shifoxiang and Shifocui. Shifoxiang had 32 kinds of volatile compounds and Shifocui had 38 kinds of volatile compounds. The main volatile components of Shifoxiang and Shifocui were green leaf volatiles. The kind and relative content of terpenes of Shifocui were more than that of Shifoxiang. Also the kind and relative content of ketones of Shifocui were more than that of Shifoxiang. There was one kind of heterocyclic compound of Shifocui. CONCLUSION: The main volatile components of Shifoxiang and Shifocui had an important role for the formation of unique aroma of high mountain ous tea. The composition and proportion of volatile components between Shifoxiang and Shifocui had certain differences. Some trace components may be associated with defense in the process of tea plant growth. The functional components from the volatile components had good medicinal value, worthy of further research.