Justine E. Vanden Heuvel
Justine E. Vanden Heuvel*
Fruiting and vegetative greenhouse-grown cranberry uprights (Vaccinium macrocarpon Ait.) were subjected to four defoliation levels (0%, 25%, 50%, 75%) on one of three dates during the growing season. Seven days following defoliation, vines were destructively harvested and carbohydrate concentration was quantified using HPLC. Prior to new growth, defoliation did not affect the concentration of total non-structural carbohydrates (TNSC) in the uprights, or the partitioning of water-soluble (i.e., sucrose, glucose, fructose) to ethanol-insoluble (i.e., starch) carbohydrates, even though uprights with lower leaf areas had higher net CO2 assimilation rates (A). At 2 weeks post-bloom, TNSC concentration was reduced in defoliated vines, although A was not affected by defoliation. Prior to harvest, TNSC concentration was reduced in vines subjected to defoliation while A was unaffected, although the positive relationship between soluble carbohydrate concentration and leaf area per upright reached an asymptote, while the direct relationship between starch concentration and leaf area remained linear. Carbohydrate production and partitioning of an upright was unaffected by the presence of a single fruit throughout the experiment. These results suggest that carbohydrate production in cranberry uprights may be sink-limited prior to fruiting, and then becomes source-limited as the growing season progresses.
Justine E. Vanden Heuvel
Flooding is often used as a pest management tool in cranberry production. The “Late Water” flood is a 1-month flood held on some Massachusetts bogs from mid-April to mid-May, and has anecdotally been related to poor vine performance. The flood was simulated at 11 °C and 21 °C on potted cranberry uprights (cv. Stevens). Over the course of the 1-month flood, total nonstructural carbohydrate concentration (TNSC) of the upright tissue decreased by 23% and 50% in the 11 °C and 21 °C treatments, respectively. Decreases in upright TNSC in the 11 °C treatment were mostly due to a substantial decrease in sucrose, while in the 21 °C treatment, sucrose, glucose, fructose, and starch all decreased significantly over the course of the flood. The greatest decrease in upright TNSC in the 11 °C treatment occurred during the first week of the flood, while in the 21 °C treatment, the greatest decrease occurred during the fourth week. Root TNSC was not affected by flooding in the 11 °C treatment, but was reduced by 39% in the 21° C treatment. Two weeks following removal from the 1-month flood, uprights in the 11° C treatment contained 9% more TNSC than uprights in the 21 °C treatment, while root TNSC from the two treatments was similar. No temperature treatment differences were evident in the uprights or roots by harvest.
Justine E. Vanden Heuvel and Martin C. Goffinet
The objective of this research was to determine the effect of water temperature during spring and fall floods on nonstructural carbohydrate concentration and anatomy/morphology of ‘Stevens’ and ‘Early Black’ cranberry vines. Potted vines of each cultivar were subjected to either a simulated 1-month late water (LW) flood in the spring at either 11 or 21 °C or a simulated 1-week harvest flood in the fall at either 12 or 20 °C. Higher water temperature resulted in decreased total nonstructural carbohydrate concentration (TNSC) during the LW flood in both uprights (i.e., vertical shoots) and roots of ‘Early Black’ and ‘Stevens’. The effect of water temperature was much less during the harvest flood than during the LW flood, but flooding at either temperature during the harvest flood had an impact on TNSC, whereas for LW floods, high water temperature was more influential than low water temperature. Clumping of chloroplasts in the palisade layer and occlusion of vascular tissues was observed in the leaves of both cultivars as a result of LW flooding. Some epidermal erosion and formation of a fungal mat was apparent on the upper epidermis of some flooded leaves. Senescence in some fine roots was visible after harvest flooding, more so in vines flooded at 20 °C than at 12 °C. Stems and major roots showed no influence of flooding on tissue senescence.
Justine E. Vanden Heuvel and Kimberly Lewers
Justine E. Vanden Heuvel and Wesley R. Autio
Anecdotal information has linked cool air temperatures before harvest with increased phenolic production in cranberry; however, there is little information available on the effect of temperature on phenolic production in cranberry fruit. The objective of this study was to determine the effect of air temperature throughout the growing season on the concentration of total anthocyanins, total flavonols, and total phenolics at harvest in fruit from seven ‘Early Black’ bogs in southeastern Massachusetts. Contrary to the anecdotal information available, correlations of temperature to fruit composition indicated that warmer temperatures early in the season (around bloom and fruit set) had the most positive impact on total anthocyanins and total flavonols. Total phenolic concentration in the harvested fruit was impacted by air temperature in the preharvest period; however, that relationship was positive.
Justine E. Vanden Heuvel and Carolyn J. DeMoranville
Competition between fruit and upright growth in cranberry has not been previously studied, but negative correlations reported between upright length/dry weight and yield indicate that sink demand from vegetative tissues may reduce fruit production. `Stevens', `Howes', and `Early Black' uprights and fruit were collected on either a weekly or bi-weekly basis through the growing seasons of 2002–04. The data indicated a shifting of resource allocation from leaf area and dry weight accumulation to fruit growth when about 1500 growing degree days (GDD, base 4.5 °C) had accumulated. Following the initial surge in fruit growth, leaf area and dry weight accumulation resumed at roughly 2300 GDD, resulting in a competition for resources with the developing fruit until after 3000 GDD. A lag phase in fruit diameter and dry weight accumulation was noted in some cultivars in some years, and may be partially due to the resumption of leaf growth. Roots, uprights, and fruit may all compete for resources during the hottest portion of the growing season.
Justine E. Vanden Heuvel and Joan R. Davenport
Five fertilizer treatments were applied to a `Stevens' cranberry bed in a 3-way split application (roughneck, 75% bloom, and 3 weeks after bloom) in Spring 2004 at State Bog in E. Wareham, Mass. Nitrogen rates were 0, 22, 45, 67, and 90 kg/ha; P was applied at 22 kg/ha, and K at 44 kg/ha. At mid-fruit development and again at preharvest, 20 vegetative and 20 fruiting uprights were collected from each plot in mid-morning. The N concentration per upright increased linearly with increased N application. Increased upright N concentration had no effect on soluble carbohydrate (sucrose + glucose + fructose) concentration, but decreased starch concentration, more so in vegetative uprights than in fruiting uprights on both sampling dates. Total nonstructural carbohydrate concentration (TNSC) was negatively impacted by increased N in vegetative and fruiting uprights at mid-fruit development, but N did not impact TNSC in either type of upright by harvest. Vegetative uprights contained greater concentrations of N, soluble carbohydrates, starch, and TNSC at both sampling dates, but contained lower concentrations of chlorophyll A and chlorophyll B.
Michelle R. Botelho and Justine E. Vanden Heuvel
American cranberry (Vaccinium macrocarpon) production sites are often flooded for pest control and crop harvest. However, little is known about how this practice affects vines. A survey was conducted in Massachusetts over a 3-year period to determine the effect of spring, fall, and winter floods on total nonstructural carbohydrate concentration (TNSC) of cranberry uprights of four cultivars. With a few exceptions, TNSC generally was unaffected or increased during the course of the 1-month “late water” flood held from mid-April to mid-May. The 48-hour “flash” flood, held in mid- to late May, generally had little effect on vine TNSC. Fall “harvest” floods, which ranged in duration from 3 to 27 days, often resulted in a decrease in TNSC, with greater decreases in TNSC occurring in early fall floods compared to late fall floods. Decreases in TNSC during the harvest flood were as great as 42%. “Winter” floods had little effect on TNSC. Path coefficient analysis indicated that flood duration, date of application, water temperature, and dissolved oxygen concentration all impacted vine TNSC during the flood, while floodwater depth had little effect. Water clarity (i.e., light penetration to the vines during the flood) also appeared to have little impact. Due to the frequent observation of TNSC decline during fall flooding, it is possible that yield potential of cranberry vines is reduced by current flooding practices.
Justine E. Vanden Heuvel and Carolyn J. DeMoranville
Competition between reproductive and vegetative growth has not been studied in cranberry. The objective of this research was to assess the growth patterns of leaves and fruit in three cranberry cultivars to determine whether vegetative and reproductive growth compete for resources. ‘Stevens’, ‘Howes’, and ‘Early Black’ uprights and fruit were collected on a weekly basis in 2002 and on a biweekly basis in 2003 and 2004 from a research bog in Massachusetts. Although growth was affected by cultivar and year, data indicated a general shifting of resource allocation from leaf area and dry weight accumulation to fruit growth at ≈1500 growing degree days (GDD, base 4.4 °C), when the initial surge of fruit growth began. Leaf area and dry weight accumulation resumed at ≈2300 GDD, resulting in a competition for resources with the developing fruit until after 3000 GDD. A lag phase in fruit diameter and dry weight accumulation was noted in some years and some cultivars and may be partially the result of the resumption of leaf growth at 2300 GDD. Fruit and shoot growth appear to compete for resources in late July through early August in Massachusetts, when carbohydrate concentration of uprights and roots is extremely low.