In recent years, frequent high temperatures and heavy rainfall in summer in China have led to a large-scale reduction in Welsh onion (Allium fistulosum L.) production. This experiment used “Hanchuan” Welsh onion as test material to analyze the effect of high temperature and waterlogging on the dry matter quality, root structure, oxygen species (ROS) metabolism, and photosynthetic performance. The results showed that waterlogging or high-temperature stress could lead to a decrease in dry matter content and root activity in various parts of Welsh onion, significantly increasing the content of reactive oxygen species (ROS) in Welsh onion roots and leaves, accelerating membrane lipid peroxidation, and significantly reduce the chlorophyll content and photosynthetic performance of Welsh onion. Among them, the damage caused by waterlogging and high-temperature interaction stress to Welsh onion is the most significant. On the 8th day of treatment, the net photosynthetic rate (Pn) of high-temperature normal water supply, normal-temperature waterlogging, and high-temperature waterlogging decreased by 53.62%, 26.4%, and 87.59%, respectively, compared to the control. The results of this study provide insight into the extent of damage to Welsh onion under different moisture and temperature conditions, which will help explore scientific methods to alleviate the damage caused by high temperature and waterlogging in Welsh onion in the future.

As a product and reproductive organ of ginger (Zingiber officinale Roscoe), the degree of rhizome bulking is a key factor in determining the yield and economic value of ginger. There are few studies on the regulatory mechanism of rhizome bulking in ginger. This study aims to identify the key hormone that regulates ginger rhizome bulking and to screen for critical hormone-associated genes. As research subjects, two ginger accessions—large (L) with a thickened rhizome and small (S) with a slender rhizome—were derived from the same parent plant. The ploidy differences between the two determine variations in gene dosage as well as differential expression patterns. The levels of eight hormones in the rhizome of L and S during different growth stages were analyzed. Differentially expressed genes (DEGs) were identified by combining third-generation transcriptome sequencing technology (PacBio SMART) with quantitative real time PCR (qRT-PCR). Through screening methods such as Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA), auxin, cytokinin, and salicylic acid were identified as the key differential hormones across various growth periods. Among these, changes in IAA level showed a positive correlation with rhizome bulking. Among them, change in IAA levels was positively correlated with the degree of rhizome bulking. Transcriptome analysis combined with qRT-PCR revealed that the auxin response factor genes ZoARF7 and ZoARF23 are likely to act as positive regulators of rhizome bulking. This study provides a theoretical foundation for elucidating the molecular mechanisms underlying hormone-mediated rhizome bulking in ginger.