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*
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
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.
Michelle R. Botelho and Justine E. Vanden Heuvel
Cranberry production involves the use of flooding for several purposes during the growing season, including pest control, winter protection, and harvest. The effect of the dissolved oxygen concentration in floodwater on carbohydrate concentration of uprights and roots during flooding was investigated using potted `Stevens' cranberry (Vaccinium macrocarpon Ait.) vines. Pots were placed in large bins filled with water to simulate a spring pest control flood (called late water) over a 21-day period. Two treatments were applied: oxygenated and nonoxygenated (control). Uprights and roots were collected every 3 days and prepared for HPLC analysis to quantify nonstructural carbohydrate concentration. Soluble sugar (sucrose, glucose, and fructose) and starch concentration, as well as total nonstructural carbohydrate (TNSC) concentration, decreased over the 3-week period in uprights but not roots regardless of treatment. Interestingly, the sucrose, glucose, fructose, and starch concentrations of uprights in the oxygenated treatment were lower than those of uprights in the control treatment throughout the experiment. This research indicates that vines in flooded bogs demonstrate a net carbon loss, resulting in reduced carbohydrate concentration available for growth and fruit production.
Justine E. Vanden Heuvel and Joan R. Davenport
Carbohydrate supply has been hypothesized to limit fruit set in cranberry (Vaccinium macrocarpon Ait.), however the limitations to carbon gain throughout the season are currently unknown. These experiments investigated the effects of light, temperature, fruit presence, and defoliation on carbon production and partitioning in potted cranberry. Fruiting and vegetative uprights (short vertical stems which bear fruit biennially) reached similar asymptotes with respect to light response, but fruiting uprights reached saturation at a lower light intensity than vegetative uprights. Runners (diageotropic vegetative stems) had a lower asymptote, higher light compensation point, and greater rate of dark respiration than uprights. Temperature had little effect on net carbon exchange rate of uprights or runners. Before new growth, defoliation did not affect the concentration of total nonstructural carbohydrates in the vegetative uprights, or the partitioning of soluble carbohydrates to starch, even though uprights with lower leaf areas had higher net CO2 assimilation. At fruit set and again at fruit maturity, defoliation reduced total nonstructural carbohydrate concentration, while net CO2 assimilation was not affected. Carbohydrate production and partitioning within an upright was unaffected by the presence of a single fruit throughout the experiment.
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.
Justine E. Vanden Heuvel and Kimberly Lewers
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.