Free, esterified, and bound phenolic fractions of berries from five different cranberry genotypes and two market samples were evaluated for their total phenolic, flavonoid, and monomeric anthocyanin contents as well as their antioxidant efficacy using TEAC, ORAC, DPPH radical, reducing power, and ferrous ion chelation capacity assays. HPLC-MS/MS analysis was performed for two of the rich sources (Pilgrim and wild clone NL2) of phenolics and high antioxidant activity. Among the genotypes, Pilgrim showed the highest phenolic and flavonoid contents and wild clones NL3 and NL2 showed the highest monomeric anthocyanin and proanthocyanidin content, respectively. Protocatechuic and syringic acids were detected only in Pilgrim, whereas luteolin 7-O-glucoside, quercetin 3-O-rhamnoside, quercetin 3-O-galactoside, proanthocyanidin B-type, and myricetin 3-O-galactoside were found in wild clone NL3 genotype. Moreover, proanthocyanin trimer A-type and dimer B-type predominated in the wild clone NL2, whereas proanthocyanidin dimer B and trimer A were predominant in Pilgrim.

Cultures of two cranberry (Vaccinium macrocarpon Ait.) cultivars,`Ben Lear' and`Pilgrim', and three cranberry clones from natural stands in Newfoundland were established in a nutrient medium containing N 6 [2-isopentenyl]adenine (2iP) from nodal and/or shoot-tip explants obtained under aseptic conditions. The cultivars differed in shoot regeneration in terms of shoot number per explant with various concentrations of 2iP over two culture periods. Best total shoot production was obtained when nodal segments were cultured in the medium supplemented with 2.5±5.0 mg 2iP l 21 (12.3±24.6 mM). With higher 2iP levels, shoots did not expand and had a high mortality rate. Nodal explants of the three clones cultured in the same nutrient medium supplemented with 2.5 mg 2iP l 21 (12.3 mM) produced three to five healthy axillary shoots per explant. In another experiment, nodal explants were more productive than shoot tips. In all experiments with subculture, there was an increase in shoot multiplication rate for all genotypes. Shoots were rooted in vitro in the same media used for shoot proliferation, but without any growth regulators. After their transfer to potting medium, almost all of the rooted plants survived. Cranberry genotypes can be efficiently propagated and maintained through nodal culture in a nutrient medium without auxin that contains 2.5±5 mg 2iP l 21 (12±25 mM).

Debnath, S. C. 2007. Inter simple sequence repeat (ISSR) to assess genetic diversity within a collection of wild lingonberry (Vaccinium vitis-idaea L.) clones. Can. J. Plant Sci. 87: 337-344. Forty-three wild lingonberry [Vaccinium vitis-idaea ssp. minus (Lodd) Hult.] clones collected from four Canadian provinces were assessed for genetic variability by using inter simple sequence repeat (ISSR). Fifteen primers generated 356 polymorphic ISSR-PCR bands. A substantial degree of genetic diversity was found among the wild collections. Cluster analysis by the unweighted pair-group method with arithmetic averages (UPGMA) separated the wild clones into four main clusters, and identified the two remaining clones as outliers. Furthermore, within four clusters, the genotypes tended to form sub-clusters that were in agreement with the principal coordinate (PCO) analysis. Geographical distribution explained 10% of total variation as revealed by analysis of molecular variance (AMOVA). The ISSR markers detected a sufficient degree of polymorphism to differentiate among lingonberry clones, making this technology valuable for germplasm management and the more efficient choice of parents in current lingonberry breeding programs. Les auteurs ont découvert un degré sensible de diversité génétique parmi les spécimens sauvages. L'analyse typologique par la méthode des paires-groupes non pondérés avec la moyenne arithmétique (UPGMA) a permis de séparer les clones en quatre groupes principaux et d'identifier les deux clones restants comme des aberrations. Par ailleurs, dans quatre groupes, les génotypes avaient tendance à former des sous-groupes concordant avec l'analyse de la coordonnée principale (PCO). La répartition géographique explique 10 % de la variation totale révélée par l'analyse de la variance moléculaire (AMOVA). Les marqueurs ISSR permettent de détecter un degré de polymorphisme suffisant pour qu'on différencie les clones d'airelle vigned'Ida, ce qui démontre l'utilité de cette technologie pour la gestion du matériel génétique et le choix de meilleurs parents pour les programmes actuels d'amélioration de cette culture.

Means within columns and parameters followed by different letters indicate significant differences at P # 0.05. DPPH = 2,2-diphenyl-1-picrylhydrazyl; GAE = gallic acid equivalents; CE = catechin equivalents; C3GE = cyanidine-3-glucoside equivalents; F.F. = fresh fruit; PM = propagation methods; TC = tissue culture; GS = growing seasons.

An efficient protocol of somatic embryogenesis (SE) has been developed for the first time in four half-high blueberry (Vaccinium corymbosum L. × V. angustifolium Ait.) cultivars. Thidiazuron (TDZ), a plant growth regulator with potential activities for shoot regeneration and shoot proliferation, was found most effective for somatic embryo formation when added to a nutrient medium at high concentration (9 µM). Although TDZ was also best for embryo germination at low concentration (2.3 µM), it was followed by zeatin at 4.6 µM for the same. Plantlets developed from SE were removed from the nutrient medium and transferred on a peat: perlite medium where 100% survival rate was acquired following the acclimatization process in a greenhouse. The concentrations of total phenolic and flavonoid contents were higher in greenhouse-grown conventionally cutting-propagated donor mother plants than those of respective SE plants for ‘St. Cloud’, ‘Patriot’ and ‘Northblue’ but not for ‘Chippewa’. The effect of propagation method and/or the older age of donor mother plants were clearly visible exclusively as the 15-year-old donor plants showed higher level of 2,2-diphenyl-1-picrylhydrazyl scavenging activity than the eight-weeks-old SE plants in all four cultivars.

No abstract

Understanding of the genetic relationship within wild lowbush blueberry (Vaccinium angustifolium Ait.) germplasm is important to establish a broad genetic base for safeguarding and for future use of the existing genetic resources. The objective of this study was to assess the genetic variability within 43 wild lowbush blueberry clones, collected from 10 communities of four Canadian provinces, and the cultivar ‘Fundy’ by using inter simple sequence repeat (ISSR) markers, with the hope to establish a reference set of lowbush blueberry germplasm for blueberry conservation, breeding and research. Thirteen primers generated 242 polymorphic ISSR‐PCR bands. A substantial degree of genetic similarity was found among the wild collections. Cluster analysis by the unweighted pair‐group method with arithmetic averages (UPGMA) separated the 41 genotypes into two main clusters, and identified the three remaining clones as outliers. Furthermore, within one main cluster, the genotypes tended to form sub‐clusters that were in agreement with the principal coordinate (PCO) analysis. Geographical distribution contributed to 27% of total variation as revealed by analysis of molecular variance (AMOVA). The ISSR‐PCR method was simple, fast and relatively inexpensive to produce useful DNA fragments and detected a sufficient degree of polymorphism to differentiate among lowbush blueberry clones, making this technology valuable for germplasm management and the more efficient choice of parents in current blueberry breeding program.

Goyali, J. C., Igamberdiev, A. U. and Debnath, S. C. 2013. Morphology, phenolic content and antioxidant capacity of lowbush blueberry ( Vaccinium angustifolium Ait.) plants as affected by in vitro and ex vitro propagation methods. Can. J. Plant Sci. 93: 1001–1008. The lowbush blueberry (Vaccinium angustifolium Ait.), a commercially important crop in eastern Canada and the United States of America, is native to North America. It is one of the richest sources of antioxidant compounds and has been reported to be a potential component in reducing the incidence of cancers and cardiovascular diseases. The aim of this study is to evaluate the effect of propagation methods on morphological characters, phenolic content and antioxidant activity. A lowbush blueberry clone, QB 9C, and a cultivar, Fundy, were studied over two growing seasons after being propagated by conventional softwood cutting (SC) and by tissue culture (TC). Significant interactions among genotypes, propagation methods and growing seasons were observed for number of flower buds, total flavonoid (TFC) and proanthocyanidin (PAC) contents and antioxidant capacity. Propagation method interacted significantly with genotypes for the number of stems per plant and total phenolic (TPC) and chlorophyll contents, and with growing season for number of flower buds, TFC and PAC. TC plants produced higher number of stems and branches compared with SC plants. TPC, TFC, PAC, chlorophyll content and antioxidant activity were found in higher levels in the leaves of QB 9C compared with those of Fundy plants. The juvenile characteristics of TC plants which are triggered by growth hormones and readily available nutrients of culture media may be responsible for differences in morphological traits and antioxidant activity.