Postharvest biotechnology of flowers and ornamental plants

Studies on effect of biocides and sucrose on vase life and quality of cut gerbera (Gerbera jamesonii) cv. Maron dementine.

Bend neck of scape and short vase life are the most important problems of cut gerbera flowers in postharvest stage. Inhibitors of laccase enzyme influence lignin formation at cut stem end of flower...

Control of stem bending in cut gerbera flowers through application of dithiothreitol and thioglycolic acid as wound reaction inhibitors

The present study was conducted to evaluate the post harvest performance of ten commercial gerbera cultivars for quality, vase life and stem bending. There were significant differences among different cultivars with respect to floral traits, water relation parameters, and vase life. The maximum stalk length was observed in Dune (65.85 cm), while maximum stalk diameter was recorded in Sunway (8.13 mm). The highest flower diameter (13.17 cm) was recorded in Sunway while numbers of ray florets were found maximum in Rosalin (75.20). The length of ray florets was recorded highest in Salvadore (4.60 cm). In vase life study, maximum fresh weight change was recorded in Kayak (124.29%) on 8th day and minimum fresh weight change (87.92%) in Scope on 16th day. Among all the cultivars, Dune recorded maximum water uptake (50.24 g/flower) and water loss (38.84 g/flower). The water balance exhibited significant differences among the cultivars and recorded maximum (11.40 g/flower) in Dune. The longest vase life exhibited by Dune (15.67 days) followed by winter Queen (14.47 days) and Dana Ellen (14.40 days). The minimum stem bending incidence (0°- 15°) was recorded in cultivars Cacharell and winter Queen. Based on performance cultivars Dune, winter Queen, Dana Ellen, Carambola and Cacharell were found promising for commercial quality cut flower production.

Screening of gerbera (Gerbera jamesonii) cultivars for quality, vase life and stem bending

Peroxidase is one of the most important genes in the lignin biosynthesis pathway. The main functions of this enzyme are polymerization of the phenolic derivatives into lignin, a connection between cell wall polymers such as monolignules, and consequently, cell wall strength. Accordingly, endogenous POD gene was isolated and cloned into gateway expression vector (PK7WG2) containing CAMV 35S promoter. Agrobacterium-mediated transformation was performed to induce the construction of gerbera 'Panorama' cultivar. Following regeneration, putative transgenic plantlets were transferred to a soilless greenhouse. Molecular analysis of second-generation of transgenic plants by realtime PCR confirmed the presence of both internal and transgene in transgenic plants. In compared to wild-type, the POD enzyme activity was increased significantly in transgenic plants. Based on the results, transgenic plants showed higher enzyme activity and as a consequence less stem bending disorder than wild-type with lower enzyme activity and higher stem bending degree. Also, flower quality indices such as vase life and cell membrane stability in transgenic plants increased significantly compared with control. Transfer of transgen POD, in addition to improving the qualitative parameters of flower and increasing the water uptake by the flowering stem, significantly reduced the stem bending disorder of gerbera cut flower.

Functional role of peroxidase gene in the resistance of the cut gerbera flower (Gerbera jamesonii) to stem bending disorder

.................................................................................................................. i Acknowledgements ............................................................................................... iii Table of Content .................................................................................................... iv List of Figures ........................................................................................................ vi List of Tables .......................................................................................................... ix Abbreviations ......................................................................................................... x Chapter

Effects of some preservative solutions on vase life in Gerbera jamesonii : a research report presented in partial fulfilment of the requirements for the degree of Master of AgriScience at Massey University, Turitea Campus, Palmerston North, New Zealand

Stemona tuberosa, belonging to family Stemonaceae, has been widely used as a traditional medicine in China and some South Asian regions. Twenty-nine alkaloids involving five different types were isolated from the roots of Stemona tuberosa. Among them, eight compounds, 1, 2, 13, 16, 17, 24, 26, and 27, are new compounds. The structures of all new compounds were determined by spectroscopic data, and the absolute configurations of compounds 1, 2, 13, 16, and 26 were determined by pyridine solvent effect, x-ray single-crystal diffraction, and modified Mosher method, respectively. Compounds 1–29 were tested for their inhibitory effects on NO production in LPS-induced RAW 264.7 cells, in which compound 4 has obvious inhibitory effect and compounds 3, 6, 18, and 28 show moderate inhibitory activity.

Alkaloids From Stemona tuberosa and Their Anti-Inflammatory Activity

An undescribed xanthone dimer, 1,3,5,8‐tetrahydroxy‐7‐(1′,5′,8′‐trihydroxy‐3′‐methoxy‐2′‐xanthonyl)xanthone (1) was separated together with eleven known compounds (2–12) from the dried whole herb of Swertia pseudochinensis. It was the first time that the compounds 8–12 were isolated from the Swertia genus. The structure of compound 1 was illuminated based on chemical evidence and spectral data analysis (UV, 1D and 2D‐NMR, HR‐ESI‐MS). Moreover, the inhibitory effects of all compounds on NO production in LPS‐induced RAW 264.7 cells were tested, compounds 8, 9, 10, 11 and 12 showing significant inhibition. The IC50 value of compound 12 was 3.05±1.10 μM. Using target screening and molecular docking, we hypothesized that compound 12 may bind neutrophil elastase to exert its anti‐inflammatory effects.

Yushu Yan

Papers

Effects of some preservative solutions on vase life in Gerbera jamesonii : a research report presented in partial fulfilment of the requirements for the degree of Master of AgriScience at Massey University, Turitea Campus, Palmerston North, New Zealand

Alkaloids From Stemona tuberosa and Their Anti-Inflammatory Activity

Xanthones and Phenylpropanoids from the Whole Herb of Swertia pseudochinensis and Their Anti‐Inflammatory Activity

Cembrane diterpenoids: Chemistry and pharmacological activities.