Polygalacturonase (PG) is an important hydrolytic enzyme involved in pectin degradation during fruit softening. However, the roles of PG family members in fruit softening remain unclear. We identified 45 PpPG genes in the peach genome which are clustered into six subclasses. PpPGs consist of four to nine exons and three to eight introns, and the exon/intron structure is basically conserved in all but subclass E. Only 16 PpPG genes were expressed in ripening fruit, and their expression profiles were analyzed during storage in two peach cultivars with different softening characteristics. Eight PGs (PpPG1, -10, -12, -13, -15, -23, -21, and -22) in fast-softening “Qian Jian Bai” (QJB) fruit and three PGs (PpPG15, -21, and -22) in slow-softening “Qin Wang” (QW) fruit exhibited softening-associated patterns; which also were affected by ethylene treatment. Our results suggest that the different softening characters in QW and QJB fruit is related to the amount of PG members. While keeping relatively lower levels during QW fruit softening, the expression of six PGs (PpPG1, -10, -12, -11, -14, and -35) rapidly induced by ethylene. PpPG24, -25 and -38 may not be involved in softening of peach fruit.

β-galactosidase (BGAL), which is an important cell wall-degrading enzyme, participates in various biological processes, but its effects on pollen tube growth (PTG) remain unclear. We identified 12 PbrBGAL genes (named PbrBGAL1–12) in the pear (Pyrus bretschneideri) genome. PbrBGAL members, containing three conserved domains and two enzyme active sites, were grouped into six subclasses. They were distributed in seven chromosomes, with dispersed duplication revealed as the main replication event. PbrBGAL genes contained 1 to 24 exons and 0 to 23 introns, with exon/intron structure mostly conserved within each subclass except for subclass E. Analyses of tissue-specific expression indicated that only PbrBGAL6 was highly expressed specifically in anther and pollen, with decreasing expression levels during PTG. The effective inhibition of PbrBGAL6 expression using antisense oligodeoxynucleotide technology dramatically decreased BGAL enzymatic activity, promoted PTG and increased cytoplasmic leakage and tip widths. Furthermore, suppressing PbrBGAL6 transcription decreased the apical total and methylated pectin contents in pollen tubes by significantly increasing transcription of PbrPME11, PbrPG14, PbrPG20, PbrPG21 and PbrPG24. We identified 12 PbrBGAL genes in the pear genome, of which PbrBGAL6 precisely modulates the apical pectin content to mediate pear PTG through its effects on PbrPME11 and PbrPGs expression. This study provides direct evidence of the involvement of BGAL in the regulation of polar PTG.

Stropharia rugosoannulata is an edible, litter-decomposing mushroom that can convert lignocellulosic residues into high-value food, yet field evidence linking cultivation environment, spent-substrate recycling, subsequent vegetable performance, and soil microbial responses remains limited. We first compared mushroom production in open-field, orchard, and plastic-greenhouse environments and then evaluated an orchard-based S. rugosoannulata–vegetable rotation using pak choi, cucumber, cowpea, and wax gourd. Mushroom yield did not differ significantly among environments, whereas orchard cultivation produced larger, more uniformly developed fruiting bodies with higher soluble protein and soluble sugar contents. Relative to non-rotated controls, rotation increased edible yield by 40.19% in pak choi, 32.75% in cucumber, 43.63% in cowpea, and 39.23% in wax gourd. The rotation treatment also increased soluble protein and soluble sugar contents and generally enhanced superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities in the four vegetables. Incorporating spent mushroom substrate increased soil organic matter, total nitrogen, available phosphorus, and available potassium, with the greatest organic-matter response in orchard soil. Amplicon analysis further showed treatment separation in principal-coordinate space and shifts in dominant bacterial phyla, including Chloroflexi, Acidobacteriota, Proteobacteria, and Actinobacteriota. These results indicate that orchard cultivation can improve the market-related quality of S. rugosoannulata and that coupling mushroom production with vegetable rotation can recycle residual substrate while improving horticultural productivity and soil fertility. Multi-season trials with complete environmental monitoring and publicly archived sequencing data are required to test the durability and generality of these benefits.