To broaden our understanding of gibberellin (GA) biosynthesis and the mechanism whereby GA homeostasis is maintained in plants, we have investigated the degree to which the enzyme GA 3-oxidase (GA3ox) limits the formation of bioactive GAs in elongating shoots of hybrid aspen (Populus tremula x Populus tremuloides). We describe the cloning of a hybrid aspen GA3ox and its functional characterizat...

Flowering of Nicotiana tabacum cv Xhanti depends on gibberellins because gibberellin-deficient plants, due to overexpression of a gibberellin 2-oxidase gene (35S:NoGA2ox3) or to treatment with the gibberellin biosynthesis inhibitor paclobutrazol, flowered later than wild type. These plants also showed inhibition of the expression of molecular markers related to floral transition (NtMADS-4 and N...

RGA (for repressor of ga1-3) and SPINDLY (SPY) are likely repressors of gibberellin (GA) signaling in Arabidopsis because the recessive rga and spy mutations partially suppressed the phenotype of the GA-deficient mutant ga1-3. We found that neither rga nor spy altered the GA levels in the wild-type or the ga1-3 background. However, expression of the GA biosynthetic gene GA4 was reduced 26% by t...

Current mass balances of C, N, and P were estimated using a model (Fluxin = Fluxout + ΔFlux) from Gamak Bay, Korea, in August 2017, where eutrophication reducing conditions are prevalent. To examine the current fluxes particulate organic carbon (POC), nitrogen (PON), phosphorus (POP), sinking re-floating sediment traps deployed, oxygen demand (SOD) chamber experiment ex-situ nutrient incubation...

The gibberellin (GA) 20-oxidase encoded by the GA5 gene of Arabidopsis directs GA biosynthesis to active GAs, whereas that encoded by the P16 gene of pumpkin endosperm leads to biosynthesis of inactive GAs. Negative feedback regulation of GA5 expression was demonstrated in stems of Arabidopsis by bioactive GAs but not by inactive GA. In transgenic Arabidopsis plants overexpressing P16, there wa...

The hormonal control of stem unit (foliar appendage and axillary structure, if present, plus subtending internode) number and length was investigated in shoots of Scots pine (Pinus sylvestris L.) and white spruce (Picea glauca (Moench) Voss). Seedlings were treated with six gibberellins (GA1, GA3, GA4, GA5, GA9 and GA20) and two auxins (indole-3-acetic acid (IAA) and naphthaleneacetic acid (NAA...

A cool temperature is preferred for lettuce cultivation, as high temperatures cause premature bolting. Accordingly, exploring the mechanism of bolting and preventing premature bolting is important for agriculture. To explore this relationship in depth, morphological, physiological, and transcriptomic analyses of the bolting-sensitive line S39 at the five-leaf stage grown at 37°C were performed ...

Preharvest fruit drop is a significant physiological problem that affects numerous commercially apple varieties, including ‘Gala.’ AVG and 1-MCP are two plant growth regulators commonly used to reduce by reducing ethylene synthesis perception, respectively. To optimize yield market acceptance, complete investigation of impacts on quality ‘Gala’ apples required. In this study, four trials were c...