Flower bud formation and flowering in chrysanthemum occur under short day conditions (SD), but the molecular basis for the switch to reproductive growth is less well understood than in model plants. Here, a spontaneous mutant able to flower under long days is described. In an attempt to reveal the pathway(s) involved in the formation of flower buds under contrasting daylengths, transcriptome sequencing was carried out in plants grown both under SD and under long day conditions (LD). A number of differentially transcribed genes involved in the various known flowering pathways were identified. Both circadian clock genes and CmFTL3 were up-regulated under SD, thereby inducing floral bud formation and flowering. The gibberellin (GA) signalling pathway-related genes GA20ox and GID1 were up-regulated in the mutant under LD, while the catabolic gene GA2ox and GAI was down-regulated, thereby inducing the transcription of CmFTL1, SOC1 and LFY. The GA content of the leaf was higher in the mutant than in the wild type under LD. When treated with GA, the mutant flowered earlier under both SD and LD, but there was no other detectable phenotype difference between the two lines. The indication was that the photoperiod pathway majorly regulates flower bud formation and flowering time in chrysanthemum under SD. GA signalling pathway only plays a subsidiary role for flowering. However, the GA signalling pathway predominated for flowering under LD.

Momordica charantia is a plant of the Cucurbitaceae family which is known as bitter gourd and grows widely in tropical and subtropical regions of the world. The various properties of bitter gourd are closely related to the substances or compounds they contain. Bitter gourd contains many secondary metabolites including alkaloids, terpenoids, steroids and flavonoids. These chemical compounds are spread in several parts of the plant such as roots, stems, leaves, and fruit. Apart from containing several organic compounds, bitter melon also contains the phytohormone gibberellin which is quite potential and useful as a biostimulant. The aim of the research was to isolate, purify, and determine the content of gibberellin (GA-3) contained in bitter gourd (M. charantia), and to determine its effect on the vegetative and generative growth of soybean plants, as well as the effect of GA-3 application on the nutritional content of soybean seeds. resulting from. Apart from that, it was also observed the effect of GA-3 application on the chlorophyll content of soybean plants, as well as the activity of the alpha-amylase enzyme in treated soybean seeds. The process of isolation and purification of GA-3 was carried out by thin layer chromatography and adsorption column chromatography on Silica Gel G-60. Characterization of GA-3 was carried out by Reversed-Phase High-Performance Liquid Chromatography (RP-HPLC), Fourier Transform Infrared (FT-IR), and Mass Spectroscopy (MS). RP-HPLC and FTIR results from gibberellin GA-3 isolates showed retention times and wave numbers that were relatively the same as GA-3 standards. From the results of the study it was found that the content of the gibberellin GA-3 hormone in bitter gourd was 4.12 mg/g dry weight. The GA-3 isolate had a significant effect on the growth of soybean plants in both the vegetative and generative phases for each parameter observed compared to the control and 1% NPK fertilizer. The protein content in soybean seeds was 38.17%. The chlorophyll content at the end of the vegetative and generative phases were 33.34 and 11.5 CCI, respectively. The addition of GA-3 isolate increased the activity of the α-amylase enzyme in soybean seeds compared to the control with an average of 271.65 U/mL.

Soil-borne beneficial microbes establish symbioses with plant hosts, and play key roles during growth and development therein. In this study, two fungal strains, FLP7 and B9, were isolated from the rhizosphere microbiome associated with Choy Sum (Brassica rapa var. parachinensis) and barley (Hordeum vulgare), respectively. Sequence analyses of the internal transcribed spacer and 18S ribosomal RNA genes combined with colony and conidial morphology identified FLP7 and B9 to be Penicillium citrinum strains/isolates. Plant-fungus interaction assays revealed that isolate B9 showed significant growth promotion effects in Choy Sum plants cultivated in normal soil, as well as under phosphate-limiting conditions. In comparison to the mock control, B9-inoculated plants showed a 34% increase in growth in aerial parts, and an 85% upsurge in the fresh weight of roots when cultivated in sterilized soil. The dry biomass of such fungus-inoculated Choy Sum increased by 39% and 74% for the shoots and roots, respectively. Root colonization assays showed that P. citrinum associates directly with the root surface but does not enter or invade the root cortex of the inoculated Choy Sum plants. Preliminary results also indicated that P. citrinum can promote growth in Choy Sum via volatile metabolites too. Interestingly, we detected relatively higher amounts of gibberellins and cytokinins in axenic P. citrinum culture filtrates through liquid-chromatography mass-spectrometry analyses. This could plausibly explain the overall growth induction in P. citrinum-inoculated Choy Sum plants. Furthermore, the phenotypic growth defects associated with the Arabidopsis ga1 mutant could be chemically complemented by the exogenous application of P. citrinum culture filtrate, which also showed accumulation of fungus-derived active gibberellins. Our study underscores the importance of transkingdom beneficial effects of such mycobiome-assisted nutrient assimilation, and beneficial fungus-derived phytohormone-like metabolites in induction of robust growth in urban farmed crops.

This study investigated the effects of exogenous gibberellic acid (GA) treatments (elongating cluster + seedless + expanding, T1; seedless + expanding, T2; expanding, T3 and water, CK) on the content of sugars, organic acids, and endogenous hormones and sink strength.Results showed that T2 treatment displayed the highest fructose and glucose levels at 100 days after treatment (DAT), whereas its effect on tartaric acid, malic acid, and citric acid concentrations at 80 and 100 DAT was relatively weak. Under GA3 treatments, both GA3, IAA, and CTK contents increased, whereas ABA contents decreased at 1, 2, 4, 8, and 48 h. Analysis of sugar phloem unloading revealed that T2 treatment exhibited the highest values during softening and ripening stages. Our findings indicate that appropriate GA3 application can positively influence sink strength by regulating sink size and activity, including berry size enlargement, sugar phloem unloading and sugar accumulation in grape sink cells.

This study investigated the efficacy of carvone, abscisic acid (ABA), gibberellin (GA3), and variable temperature in managing dormancy and sprouting in aeroponically grown mini-tuber potato seeds. Results showed that carvone treatment effectively reduced weight loss rate by 12.25% and decay rate by 3.33% at day 25, compared to control. ABA treatment significantly enhanced germination rate to 97.33%. GA3 treatment resulted in the longest sprouts of 14.24 mm and reduced MDA content by 23.08% at day 30, indicating its potential in shortening dormancy and maintaining membrane integrity. Variable temperature treatment showcased a balanced performance in reducing weight loss and maintaining a lower relative conductivity, indicating less cellular damage. Enzymatic activities of α-amylase, CAT, and SOD were modulated by the treatments, ensuring a balanced enzymatic environment for seed vitality. These findings provide a robust foundation for refining post-harvest management strategies to optimize germination uniformity and preserve the quality of aeroponic potato seeds during extended dormancy, promising enhanced yield and productivity in potato cultivation.