2.51 and 2.54 pg/2C, respectively. Table 2. DNA content and calculated ploidy levels of selected standards, section Hemimyrtillus species, and section Hemimyrtillus × Vaccinium corymbosum hybrids. Fertility and crossing of the parents Female
The genus Vaccinium is a member of the Ericaceae family, which includes ≈400 species. Of all the cultivated species and hybrids in this genus, highbush blueberry ( V. corymbosum L.) is the most commonly known species that produces small, edible
had the potential to act as a bridge between taxonomic sections and ploidies in Vaccinium ( Ehlenfeldt et al., 2018 ). In this study, we sought to determine the feasibility of crossing 4 x V. meridionale with 4 x V. corymbosum to facilitate
Blueberries (family Ericaceae, genus Vaccinium , commonly section Cyanococcus ) are a diverse taxonomic group, and blueberries currently in commercial production represent three major Vaccinium species and two ploidy levels: 4 x V
. Vicente, A. 2010 Effect of preharvest calcium applications on postharvest quality, softening and cell wall degradation of two blueberry ( Vaccinium corymbosum ) varieties Postharvest Biol. Technol. 58 98 103 Bednarska, E. 1991 Calcium uptake from the
Abstract
Ericoid mycorrhizae were measured on roots of wild and cultivated highbush blueberries (Vaccinium corymbosum L.) from 7 locations in southeastern North Carolina over 4 sampling dates. An adequate clearing and staining procedure was developed specifically for observing endomycorrhizae in blueberry roots. Abundant mycorrhizae were found in wild blueberry plants, but few mycorrhizae were noted in cultivated plants. Phosphorus levels were lower in the wild than in the cultivated blueberry soils at most locations.
Abstract
Mechanical pollination trials using air blasts and vibration to distribute pollen were conducted on the highbush blueberry, Vaccinium corymbosum cvs. ‘Jersey’ and ‘Rubel’. Neither treatment nor a simultaneous combination of the two gave commercial fruit set for either cultivar. Mechanical trials on the ‘Rubel’ cultivar indicated almost total failure to effect pollination. Production from ‘Jersey’ cultivar mechanical pollination trials was more promising. However, low seed numbers indicated that the increased production of this cultivar might be due to its tendency to set fruit parthenocarpically.
Abstract
Number of plump seeds and fruit size were correlated with pollen viability in intercrosses of Vaccinium corymbosum L. There was no relation between pollen viability and percent fruit set, days to fruit maturity, or seed weight.
Two-year-old highbush blueberry bushes (Vaccinium corymbosum L. `Collins') were treated in Mar. 1985 with diuron or simazine at 2.2 or 4.5 kg a.i./ha. No residues were detected by reverse-phase high-performance liquid chromatography-ultraviolet absorbance detection (HPLC-UV) from treated berries that were harvested in June. Methiocarb was applied in May 1986 at 0.84 and 3 kg·ha-1 over the top of 3-year-old `Collins' when the berries began to ripen. Reverse-phase HPLC-UV of berries treated with methiocarb at 3 kg·ha-1 had combined residues of methiocarb and its sulfone and sulfoxide metabolites of 13.1 ppm from unrinsed and 7 ppm from rinsed berries harvested on the day of treatment; 4.9 ppm from unrinsed and 4 ppm from rinsed berries harvested 4 days after treatment; and 2.4 ppm from unrinsed and 2.5 ppm from rinsed berries harvested 8 days after treatment. Unrinsed berries treated with methiocarb at 0.84 kg·ha-1 had 5.7 ppm residue on the day of treatment and 1 ppm 8 days later. Residues from berries treated with methiocarb at 0.84 or 3 kg·ha-1 were below the legal tolerance level of 5 ppm after the required 7-day waiting period. Chemical names used: n'-(3,4-dichlorophenyl)-N,N -dimethylurea (diuron); 6-chloro- N,N' -diethyl-1,3,5-triazine-2,4-diamine (simazine); 3,5-dimethyl-4-(methylthio)phenol methylcarbamate (methiocarb).
Pollen from six southern highbush blueberry cultivars derived from Vaccinium corymbosum L. and one or more other species (V. darrowi Camp, V. ashei Reade, and V. angustifolium Aiton) was incubated on nutrient agar to determine tetrad viability, pollen tube growth rates, and incidence of multiple pollen tube germinations. `Avonblue' pollen had a significantly lower tetrad germination percentage than `Georgiagem', `Flordablue', `Sharpblue', `Gulfcoast', or `O'Neal', all of which had >90% viable tetrads. The in vitro growth rate of `O'Neal' pollen tubes was significantly higher than the growth rates of `Sharpblue' and `Georgiagem pollen tubes. Of those tetrads that were viable, more than two pollen tubes germinated from 83% and 91% of the `Gulfcoast' and `Sharpblue' tetrads, respectively, while only 11% of the `Flordablue' tetrads produced more than two pollen tubes. The total number of pollen tubes germinated per 100 tetrads ranged from 157 (`Flordablue') to 324 (`Sharpblue'), resulting in actual pollen grain viabilities ranging from 39% to 81%. Genetic differences in pollen vigor, as indicated by pollen viability, pollen tube growth rates, and multiple pollen tube germinations, may influence blueberry growers' success in optimizing the beneficial effects of cross-pollination on fruit development.