Pear is one of the main fruits with thousands of years of cultivation history in China. There are more than 2000 varieties of pear cultivars around the world, including more than 1200 varieties or cultivars in China (Legrand et al., 2016). Xinjiang Uygur Autonomous Region is an important pear production region in China with 30 of varieties or cultivars. Pyrus sinkiangensis is the most popular variety, which is mainly distributed in Xinjiang (Zhou et al., 2018). Chlorogenic acid (CGA), p-coumaric acid, and arbutin are the main polyphenols in pear fruit, and their levels show great differences among different varieties (Li et al., 2014). CGA is a potential chemo-preventive agent, which possesses many important bioactivities including antioxidant, diabetes attenuating, and anti-obesity (Wang et al., 2021). Therefore, the specific CGA content of a variety is considered the embodiment of the functional nutritional value of pears.
Chlorogenic Acid ; Fruit ; Gene Expression Profiling ; Pyrus/genetics* ; Transcriptome

Objective To investigate the shedding of CAV2-ΔE3-CGS after immunization and the background of canine adenovirus (CAV) infection, and to establish a dual fluorescent quantitative PCR detection method for rabies virus (RV) and canine adenovirus type 2 (CAV2). Methods A dual fluorescent quantitative PCR detection method was established by designing specific primers and probes for E1 gene of CAV and G gene of RV for the detection of CAV2-ΔE3-CGS. Oral swabs, anal swabs and environmental samples of stray dogs from experimental animal farm and dog detention center were tested. Results The standard curves generated by this method were Y=-3.351 × logX + 44.895, R² = .999 and Y=-3.413 × logX + 45.192, R²=0.996, respectively. The linear relationships were good, and the minimum detection limits were both 102 copies/μL. CAV2-ΔE3-CGS was not detected in experimental animal farm. CAV was detected in dog detention center, and the positive rates were 5.88% (5/85) in oral swabs, 8.24% (7/85) in anal swabs, and 4% (1/25) in environmental samples. Conclusion The dual fluorescent quantitative PCR method can be used for the detection of CAV2-ΔE3-CGS after immunization and the investigation of CAV infection. The present study has shown that no CAV2-ΔE3-CGS has been detected after immunization and CAV infection rate of stay dogs is low in Shanghai. CAV2-ΔE3-CGS oral immunization meets requirement and is applicable.