Jincheng orange (Citrus sinensis Osbeck) is widely grown in Chongqing, China, and is commonly consumed because of its characteristic aroma contributed by the presence of diverse volatile compounds.  The changes in aroma during the development and maturation of fruit are indicators for ripening and harvest time.  However, the influence of growth stages on the volatile compounds in Jincheng orange remains unclear.  In addition, volatiles originate from fatty acids, most of which are the precursors of volatile substances.  On this basis, gas chromatography–mass spectrometry (GC–MS) was performed to elaborate the changes in volatile constituents and fatty acids as precursors.  This study tested proximately 60 volatiles and 8 fatty acids at 9 growth and development stages (AF1–AF9).  Of those compounds, more than 92.00% of total volatiles and 87.50% of fatty acids were terpenoid and saturated fatty acids, respectively.  As shown in the PCA plot, the AF5, AF6, and AF9 stages were confirmed as completely segregated and appeared different.  In addition, most of the volatiles and fatty acids first increased at the beginning of the development stage, then decreased from the AF6 development stage, and finally increased at the AF9 maturity stage.  Moreover, the highest contents of terpenoid, alcohols, aldehydes, ketones, and saturated fatty acids in Jincheng orange peel oil were d-limonene, linalool, octanal, cyclohexanone, and stearic acid during development stages, respectively.  Our results found that the growth stages significantly affected the volatile constituents and precursors in Jincheng orange peel oil.

The fresh postharvest golden needle mushroom (Flammulina velutipes) sporocarp has a high moisture content and crisp texture, but it still has high physiological activity and respiration, leading to senescence and quality deterioration.  Treatments with 1-methylcyclopropene (1-MCP) and polypropylene (PP) crispers were used to study the changes of lignification and softening of F. velutipes during storage.  The main findings were as follows: the crisper packaging could effectively prolong the storage time of F. velutipes; either the 1-MCP treatment, crisper packaging or the combination of the two treatments could significantly inhibit the accumulation of lignin and the decreases in the contents of cellulose and pectin, and had certain inhibitory effects on the activities of enzymes involved in lignification and softening including phenylalanine ammonia-lyase (PAL), cinnamyl alcohol dehydrogenase (CAD), cellulase (Cx), pectin methylesterase (PME) and polygalacturonase (PG).  Among them, the inhibitory effect of the crisper packaging was higher than the 1-MCP treatment, while the combination of the two treatments was the best.  The results of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) showed that the crisper packaging in combination with the 1-MCP treatment could effectively maintain the integrity and stability of the F. velutipes cellular structure and inhibit the emergence of plasmolysis to prevent cell membrane rupture.  The transcription levels showed that the crisper packaging and the combination of the 1-MCP treatment and crisper packing could effectively affect the expression of genes for enzymes related to lignification and softening of F. velutipes.  In conclusion, 1-MCP and PP crispers could delay the lignification and softening of F. velutipes during storage.

    The structural characteristics of protein body accumulation in different endosperm regions of hard wheat cultivar (XM33) and soft wheat cultivar (NM13) under drought stress were investigated. Drought stress treatment was implemented from plant regreening to the caryopsis mature stage. Microscope images of endosperm cells were obtained using resin semi-thin slice technology to observe the distribution and relative area of protein body (PB). Compared with NM13, relative PB area of XM33 was significantly higher in sub-aleurone endosperm region. The amount of accumulation, including the size and relative area of PB, in two wheat cultivars was higher in sub-aleurone region than that in central region at 18 days post anthesis (DPA). Drought stress significantly enhanced the sizes and relative areas of PBs in the dorsal and abdominal endosperms in two wheat cultivars. Particularly for dorsal endosperm, drought stress enhanced the relative PB area at 18 DPA and NM13 (5.0% vs. 6.73%) showed less enhancement than XM33 (5.49% vs. 8.96%). However, NM13 (9.58% vs. 12.02%) showed greater enhancement than XM33 (10.25% vs. 11.7%) at 28 DPA. The protein content in the dorsal and abdominal endosperms of the two wheat cultivars decreased at 12 DPA and then increased until 38 DPA. Drought stress significantly increased the protein contents in the two main regions. From 12 to 38 DPA, the amount of PB accumulation and the protein content were higher in XM33 than those in NM13. The results revealed that PB distribution varied in different endosperm tissues and that the amount of PB accumulation was remarkably augmented by drought stress.