Organic Supplementation of Vaccinium corymbosum Micropropagation Media.

The best Vaccinium corymbosum plant growth under in vitro conditions can be achieved by using the right composition and pH of the medium. For the initial phase of in vitro culture, a combination of cytokinins-mostly zeatin-can usually be used. Organic supplementation of the medium enables the use of a replacement for the expensive natural cytokinin used in micropropagation of highbush blueberry. This chapter describes the experiments with silicon Hydroplus™ Actisil (Si), coconut water (CW), and different pH (5.0; 5.5, and 6.0) as a stress factor. The addition of 200 mg dm-3 silicon solution and 15% coconut water strongly stimulated highbush blueberry plant growth in vitro. Moreover, silicon solution benefits the negative effects of higher pH of the medium used for micropropagation of V. corymbosum. Maximum vegetative development of blueberry explants was obtained at pH 5.

In Vitro Propagation and Variation of Antioxidant Properties in Micropropagated Vaccinium Berry Plants-A Review.

The berry crops in genus Vacciniun L. are the richest sources of antioxidant metabolites which have high potential to reduce the incidence of several degenerative diseases. In vitro propagation or micropropagation has been attractive to researchers for its incredible potential for mass production of a selected genotype in a short time, all year round. Propagation techniques affect the antioxidant activity in fruits and leaves. Total antioxidant activity was higher in the fruit of in vitro propagated plants compare to the plants grown ex vivo. This review provides critical information for better understanding the micropropagation and conventional propagation methods, and their effects on antioxidant properties and morphological differentiation in Vaccinium species, and fills an existing gap in the literature.

Polyphenolic profiles and antioxidant and antiradical activity of Italian berries from Vaccinium myrtillus L. and Vaccinium uliginosum L. subsp. gaultherioides (Bigelow) S.B. Young.

Total soluble polyphenols (TSP), total monomeric anthocyanins (TMA), radical scavenging activity (RSA), ferric reducing antioxidant power (FRAP), and a number of anthocyanins, phenolic acids, coumarins, flavanols, dihydrochalcones and flavonols were investigated in Tuscan bilberry (i.e. Vaccinium myrtillus) and "false bilberry" (i.e. Vaccinium uliginosum subsp. gaultherioides Bigelow). V. myrtillus berries showed much higher TSP, TMA, RSA and FRAP values than V. uliginosum subsp. gaultherioides fruits. Moreover, very different profiles of individual phenolics were observed in the two species, being V. myrtillus mainly characterised by delphinidin and cyanidin glycosides, together with chlorogenic acid, and V. uliginosum subsp. gaultherioides dominated by malvidin derivatives and flavonols. Strong differences between the two species regarded also metabolites investigated herein for the first time, such as scopoletin, which was approximately two magnitude orders higher in V. uliginosum subsp. gaultherioides than in V. myrtillus berries. Very different abundances were also highlighted for cryptochlorogenic acid and quercetin-3-rhamnoside that were about ten-fold higher in bilberry than in "false bilberry". When the anthocyanin composition pattern of Tuscan "false bilberry" was compared to those elsewhere reported for V. uliginosum fruits harvested in different world areas, some important differences were observed.

Relationship between polyphenol content and anti-influenza viral effects of berries.

BACKGROUND: Berries are known to have many kinds of biological activities. We focused on their antiviral effect, which has not yet been well evaluated. RESULTS: We compared the anti-influenza viral effects of berries belonging to the genus Vaccinium - 35 species of blueberry (Vaccinium cyanococcus), the Natsuhaze (Vaccinium oldhamii), bilberry (Vaccinium myrtillus) and cranberry (Vaccinium oxycoccos)- with those belonging to the genus Ribes, i.e. blackcurrant (Ribes nigrum). Only Elliott and Legacy among Northern Highbush varieties but many Rabbiteye varieties such as Austin, Baldwin, Brightblue, Festival, T-100 and Tifblue showed anti-influenza viral activity. Natsuhaze, bilberry, cranberry and blackcurrant had high antiviral effects. A relationship was observed between the antiviral effect and total polyphenol content. CONCLUSIONS: Antiviral effects were found to differ markedly between berry species. Rabbiteye varieties tended to have higher antiviral effects than Northern, Southern and Half Highbush blueberry varieties. We also found that Natsuhaze, which has recently been harvested in Japan as a potential functional food, had an antiviral effect comparable to that of bilberry, cranberry and blackcurrant. There was a positive relationship between antiviral activity and polyphenol content, indicating the possibility that polyphenol is one of the key factors in the antiviral effects of berries.

Effects of southern highbush blueberry cultivar and treatment threshold on flower thrips populations.

In Florida, southern highbush (SHB) blueberries (Vaccinium corymbosum L. x Vaccinium darrowi Camp) are grown for a highly profitable early season fresh market. Flower thrips are the key pest of SHB blueberries, and Frankliniella bispinosa (Morgan) is the most common species found. Flower thrips injure blueberry flowers by feeding and ovipositing in all developing tissues. These injuries can lead to scarring of developing fruit. The objectives of this study were to determine the relationship between thrips and yield in different SHB blueberry cultivars and to determine an action threshold. Experiments were conducted during early spring 2007 and 2008 on four farms; a research farm in Citra, FL; and three commercial farms, two in Hernando Co., FL., and one in Lake Co., FL. At the Citra farm, 'Emerald', 'Jewel', 'Millennia', and 'Star' blueberries were compared in 2007, and all but Star were compared in 2008. On the Hernando and Lake Co. farms, two treatment thresholds (100 and 200 thrips per trap) and an untreated control and four cultivars (Emerald, Jewel, Millennia, and 'Windsor') were compared. Emerald consistently had more thrips per trap and per flower than the other cultivars on all four farms. However, this did not always lead to an increase in fruit injury. Thrips numbers exceeded the threshold on only one farm in 2007, and there was a significantly lower proportion of injured and malformed fruit in the 100 thrips per trap threshold treatment compared with the control on this farm.

Honey bee (Hymenoptera: Apidae) pollination of rabbiteye blueberry Vaccinium ashei var. 'Climax' is pollinator density-dependent.

In a 2-yr field study, mature orchard plants of rabbiteye blueberry (Vaccinium ashei Reade variety 'Climax'), plus potted pollenizers ('Premier') were caged with varying densities of honey bees (0, 400, 800, 1,600, 3,200, 6,400, or 12,800 bees plus open plot) during the bloom interval. The rate of legitimate flower visits tended to increase as bee density increased within a range of 400-6,400 bees; there were more legitimate visits in cages with 6,400 bees than in those with < or = 1,600 bees. Similarly, within a range of 400-6,400 bees there was a trend for a corresponding increase in fruit-set with means ranging from 25.0 to 79%. Fruit-set was higher in cages with 6,400 or 3,200 bees than in those with < or = 800 bees. Regression analyses showed that fruit-set increased linearly with the rate of legitimate bee visits. Mean weight of berries was unaffected by bee density but varied significantly between years. Within a range of 0-3,200 bees/cage the average seeds per berry tended to increase with increasing bee density; there were more seeds in open plots than in cages with 12,800 honey bees or < or = 1,600 bees. Sucrose content ranged from 12.1 to 16.7% and fruits tended to have more sugar in cages with lower bee densities. Speed of ripening tended to be higher in cages with higher bee densities. Earlier work has shown that the effectiveness of Apis mellifera L. as a pollinator of rabbiteye blueberry is variety-dependent. Our data indicate that the effectiveness of A. mellifera is also bee density-dependent.