Early Harvest Effects on Hydrophilic Phenolic Components of Extra Virgin Olive Oils Cvs. 'Ayvalik', 'Memecik' and 'Topakasi'.

The study was conducted to determine the effects of cultivar, harvest period and their interaction on the hydrophilic phenolic components extra virgin olive oils of the cultivars 'Ayvalik', 'Memecik' and 'Topakasi'. Olives were collected at three different harvesting periods; (1) early harvest period-1 (Beginning of spotting), (2) early harvest period-2 (End of spotting), and (3) optimum harvest period. Oils were extracted using an abencor system. HPLC (High-performance liquid chromatograph) technique was used to quantify The phenolic compounds including: tyrosol (p-HPEA), hydroxytyrosol (3,4-DHPEA), luteolin, rutin, quercetin, catechin, sinapinic acid, p-coumaric acid, cinnamic acid, vanillin, vanillic acid, ferulic acid and gallic acid were quantified using HPLC. The results indicated that the effects of harvest period on the phenolic components were variety dependent. At the early harvest period-1, 'Memecik' and 'Topakasi' had the highest efficiency in luteolin, cinnamic acid, vanillic acid, and ferulic acid contents, while 'Ayvalik' had the highest efficiency in hydroxytyrosol, sinapinic acid, p-coumaric, vanillin and ferulic acid contents. At the optimum harvest period, 'Ayvalik' had the highest efficiency in luteolin, tyrosol and gallic acid contents, while 'Topakasi' had the highest efficiency in tyrosol, hydroxytyrosol and rutin content. The highest phenolic content was detected in the early harvest period-1. The content of tyrosol linearly increased with the progress of maturity harvest period, whereas the contents of the sinapinic acid, vanillin, vanilic acid and ferulic acid decreased. The oils of 'Memecik' variety had significantly higher phenolic content than those of 'Ayvalik' and 'Topakasi' varieties.

Biolistic DNA Delivery in Turfgrass Embryonic Callus Initiated from Mature Seeds.

We describe a protocol for the establishment and preparation of creeping bentgrass (Agrostis stolonifera L.) cultivar "Penn A-4" embryonic calli, biolistic transformation, selection, and regeneration of transgenic plants. The embryonic callus is initiated from mature seeds, maintained by visual selection under the dissecting microscope and subjected to bombardment with plasmid DNA containing a bialaphos-resistance (bar) gene. PCR, Southern, and Northern blot analyses are used to confirm the transgene integration and expression.

Manipulating expression of tonoplast transporters.

Plant vacuoles have multifaceted roles including turgor maintenance, cytosolic pH and ionic homeostasis, plant protection against environmental stress, detoxification, pigmentation, and cellular signaling. These roles are achieved through the coordinated activities of many proteins in the tonoplast (vacuolar membrane), of which the proton pumps and ion transporters have been modified for improved abiotic stress tolerance in transgenic plants. Here we describe a method to manipulate vacuolar H(+)-pyrophosphatase in turfgrass and evaluate the impact of the modified tonoplast on the phenotype, biochemistry, and physiology of the transgenics. Creeping bentgrass (Agrostis stolonifera L.) plants overexpressing an Arabidopsis vacuolar H(+)-pyrophosphatase AVP1 exhibited improved growth and enhanced salt tolerance, likely associated with increased photosynthesis, relative water content, proline production, and Na(+) uptake. These transgenic plants also had decreased solute leakage in the leaf tissues and increased concentrations of Na(+), K(+), Cl(-), and total phosphorus in the root tissues. Similar strategies can be employed to manipulate other tonoplast transporters and in other plant species to produce transgenic plants with improved performance under various abiotic stresses.