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The stolon is the main asexual reproductive organ of the medicinal plant Tulipa edulis and has special morphology. In the greenhouse experiment presented herein, the dynamic changes in carbohydrates and related enzymes, proteins, and endogenous hormones of stolons during T. edulis stolon formation were investigated. The results showed that the content of total soluble sugar, sucrose, reducing sugar, fructose, and starch were all significantly enhanced in the middle period when stolon emerged and maintained at relatively high levels until the later period of stolon formation, while protein content decreased during stolon formation. The activities of amylase (AMY), sucrose phosphate synthase (SPS), and sucrose synthase (SS) peaked in the initial period and were negatively correlated with soluble sugars. However, adenosine diphosphoglucose pyrophosphorylase (AGPase) activity increased as stolon formation progressed, and the changes in soluble starch synthase (SSS), granule-bound starch synthase (GBSS) activities presented a single peak, reaching their maximums in the middle period. AGPase, SSS, and GBSS activities were all positively related to starch content. Moreover, quantitative real-time polymerase chain reaction (qRT-PCR) verified the changes in SS and SSS activities via the expression levels of the SS, SSSI, and SSSII genes. The gibberellin (GA) and zeatin riboside (ZR) content attained their maximum in the initial period of stolon formation. Indole-3-acetic acid (IAA) and abscisic acid (ABA) remained at high levels during the initial and middle period and decreased significantly during the later period of stolon formation, inversely to the ratio of ABA:IAA. Analysis of the physiological changes in T. edulis stolon indicated that the accumulation of soluble sugars and starch via various enzymes, a high level of IAA and a low ABA to IAA ratio mainly contributed to stolon development of T. edulis. This paper explored carbohydrate levels and endogenous hormones profiles during stolon formation, which provided the theory basis for further regulating stolon growth of T. edulis.

Vitis amurensis grape cultivars and hybrids are mainly used to make wines in Northeast Asia with a cold winter. Anthocyanidin glucosylation at 5-O position catalyzed by 5-O-glucosyltransferase (5GT) in grape skins is crucial for color stability of red wines. To study 5GT functions in anthocyanidin diglucosides synthesis of V. amurensis, 20 5GTs were preliminarily identified from a genome-wide characterization of the UDP-glycosyltransferase family according to the reported 5GTs, which were also performed phylogenetic and bioinformatics analysis. Two important 5GTs, Vitvi0900582.t01 and Vitvi05g01269.t01, were screened through analyses of anthocyanidin diglucosides accumulation and gene expression in berry skins of three representative grape cultivars with significant differences in anthocyanin glycosylation. Fourteen alleles of each of the 5GTs were cloned from 14 V. amurensis cultivars and hybrids as well as from V. vinifera ‘Cabernet Sauvignon’, and sequence analysis and functional prediction were performed. From three perspectives of phenotype, transcriptional level, and genotype, it has been found that the functional allele at the Vitvi0900582.t01 locus of Chr 9 played a decisive role in the synthesis of abundant anthocyanidin diglucosides in V. amurensis. In addition, the trace anthocyanidin diglucosides detected in V. vinifera ‘Cabernet Sauvignon’ were led by the functional allele at the Vitvi05g01269.t01 locus of Chr 5. This study provides preliminary data for further research on the regulatory mechanism of anthocyanidin diglucosides in the grapes with the V. amurensis pedigree to improve their wine quality in future breeding efforts.