`Rogers Red McIntosh' apple (Malus domestica Borkh.) trees on MM. 111, MM. 106, M.7a, or M.26 were planted in 1984 on an old orchard site, diagnosed with an apple replant disease (ARD) problem. Soil treatments included Telone c-17, Vorlex, Nemacur 3, or not treated. After six years, tree performance problems usually associated with severe ARD did not develop. Lesion nematode [Pratylenchus penetrans (Cobb) Filipjev and Schuurmans-Stekhoven] populations feeding within or on the surface of roots were not affected by nematicide treatments nor rootstocks, even though slightly damaging levels were found in 1986. At the end of the sixth growing season, trunk cross-sectional areas were similar for trees in treated and in untreated soils. Trees on MM. 111 and MM. 106 were the largest, and those on M.26 were the smallest. Cumulative yield was not influenced by soil treatments, but trees on MM. 111 produced the greatest cumulative yields, whereas trees on M.26 were the most yield efficient.
Joseph F. Costante, Wesley R. Autio, and Lorraine P. Berkett
Wesley R. Autio, Duane W. Greene, and William J. Lord
`Summerland Red McIntosh' apple trees (Malus domestica Borkh.) on M.9/A.2, O.3, M.7 EMLA, M.26 EMLA, M.7A, OAR1, and Mark were evaluated over 10 years. Trees on M.7 EMLA and OAR1 were the largest, and trees on Mark were the smallest. Trees on M.7 EMLA produced the highest yields per tree, and those on OAR1 and Mark produced the lowest. The most yield-efficient trees were on O.3 and Mark. The least efficient trees were on OAR1. Fruit from trees on O.3, M.26 EMLA, or M.9/A.2 generally were the largest, and fruit from trees on OAR1 generally were the smallest. Red pigment development was inversely proportional to canopy size, with Mark resulting generally in the most red pigmentation and M.7 EMLA and M.7A generally resulting in the least. Methods of presenting productivity were compared. Presentation of yield per land area occupied or projected yield per planted area were biased in experiments where only some trees naturally would exceed the allotted space and, therefore, were containment pruned and where tree-to-tree competition was directly proportional to tree size. Yield efficiency was a less biased estimate. Further, in single-row planting systems with trees spaced at optimal densities, small trees must be more efficient than large trees to obtain similar yields.
Angela M. Madeiras, Thomas H. Boyle, and Wesley R. Autio
The effects of warm stratification and cold stratification, gibberellin-3 (GA3) concentration, potassium nitrate concentration, light, and duration of surface sterilization on the germination of downy phlox (Phlox pilosa L.) seeds were studied. Germination after 21 days (G21), days to 50% germination (T50), and number of days between 10% and 90% final germination (T90–T10) were calculated for each treatment. Total germination percentage was most significantly improved by cold stratification at 5 ± 2 °C for 10 weeks after warm stratification at 20 °C for 2 weeks; however, a substantial amount of germination occurred during the prestratification period, thus resulting in a crop with poor uniformity. A total of 10 mg·L−1 GA3 significantly improved the G21, T50, and T90–T10 values. Although GA3 concentration and duration of cold stratification period interacted significantly when the two were combined, the additive effects of GA3 and cold stratification did not significantly improve G21 values over those obtained with GA3 alone nor were T50 values improved over those obtained with cold stratification alone. Potassium nitrate did not influence the T50 and T90–T10 values and improved G21 only slightly. Light was found to be necessary for germination. Surface sterilization with 10% bleach decreased the growth of fungi on seeds but had no significant effect on the germination responses of P. pilosa seeds. Application of GA3 at 10 mg·L−1 is a promising method for improving seed germination in perennial Phlox species.
Hilary A. Sandler, Carolyn J. DeMoranville, and Wesley R. Autio
A 2-year field trial examined the interaction of nitrogen rate, vine density, and weed management options for establishing new cranberry (Vaccinium macrocarpon) plantings. Utilizing the vigorous hybrid, `Stevens', the cost-efficiency of the treatment combinations was evaluated by combining cranberry and weed biomass data with various economic estimates. The most cost-effective production scheme for establishing new cranberry beds is to plant vines at a low density, use moderate rates of nitrogen, and apply an annual application of a preemergence herbicide. This combination produced substantial vine coverage at very low cost, reduced weed biomass by 85% compared to untreated plots, and gave the best weed control per dollar spent. Growers may opt for other reasonably successful combinations that involve higher labor costs if they can produce their own cuttings (reducing initial costs) or if they are farming with the intent to reduce overall synthetic inputs.
Wesley R. Autio, William J. Lord, and Peter L.M. Veneman
`Marshall McIntosh' apple trees (Malus domestics Borkh.) on M.7A, M.26, M.9/MM.106, and M.9/MM.111 were planted at 10 locations in Massachusetts. After seven growing seasons, trees on M.7A were the largest and trees on M.26, M.9/MM.106, and M.9/MM.111 were similar in size on all sites. Trees on M.7A outyielded (1986-88) trees on the other rootstock at only three of the 10 sites. At three sites, trees on M.7A and, M.26 were similarly yield-efficient, but on all other sites trees on M.7A were the least efficient. Trees on M.9/MM.111 and M.9/MM.106 were similarly efllcient on all but two sites.
Catherine C. Neto, Christine A. Dao, Michelle R. Salvas, Wesley R. Autio, and Justine E. Vanden Heuvel
Several insect herbivores have been anecdotally reported to prefer ‘Howes’ cranberry leaves (Vaccinium macrocarpon) over those of ‘Early Black’. A series of studies were undertaken to determine whether these anecdotal reports are accurate and to compare phenolic profiles in the foliage of ‘Early Black’ and ‘Howes’ for compounds that differ in concentration and could be further investigated as possible feeding deterrents. Gypsy moth larvae (Lymantria dispar) demonstrated a significant feeding preference for ‘Howes’ over ‘Early Black’. Red-headed flea beetle adults (Systena frontalis) demonstrated a similar but not statistically significant trend, whereas cranberry weevil (Anthonomus musculus) did not prefer either cultivar. Compounds giving rise to six peaks in the phenolic profile were significantly greater in concentration in ‘Early Black’ than ‘Howes’ on at least one of three sampling dates during the growing season. Five of these compounds were isolated from leaves harvested at the June time point coinciding with gypsy moth infestation and identified as: 5-O-caffeoylquinic acid, 3-O-p-coumaroylquinic acid, 5-O-p-coumaroylquinic acid, quercetin-3-O-galactoside, and quercetin-3-O-rhamnoside.
Wesley R. Autio, Duane W. Greene, Daniel R. Cooley, and James R. Schupp
Increasing the N application rate (in the form NH4NO3 to newly planted `Marshall McIntosh'/M.9 apple (Malus domestica, Borkh.) trees beyond 76 g N per tree per year reduced growth in the first two growing seasons. Peat moss or composted manure mixed into the planting hole of `Royal Gala'/M.26 increased growth in the first growing season after planting. The soil-active fungicides, fosetyl-Al and metalaxyl, increased trunk and shoot growth of `Royal Gala'/M.26 in the first season after planting. Mulching enhanced growth of `Gala'/M.26 only in the third season after planting, a season during which the region experienced a drought. Mulching significantly increased bloom on `Gala'/M.26 2 years after planting. The growth of `Royal Gala'/M.26, `Marshall McIntosh'/M.26, and `Ace Delicious'/M.26 was not affected by planting technique planting by hand in 61-cm augered holes vs. planting with a mechanical tree planter. Chemical names used N-(2,6-dimethyl-phenyl)-N-(methloxyacetyl)alanine methyl ester (metalaxyl); aluminum tris (O-ethyl phosphonate) (fosetyl-Al); 1,1'-dimethyl-4-4'-bipyridinium ion (paraquat); isopropylamine salt of N-(phosphonomethyl) glycine (glyphosate).
Brett Suhayda, Carolyn J. DeMoranville, Hilary A. Sandler, Wesley R. Autio, and Justine E. Vanden Heuvel
Sanding and pruning are two practices used in the cranberry (Vaccinium macrocarpon) industry for vine management and yield stimulation. This study compared varying levels of sanding and pruning on vine canopy characteristics, yield, and economic returns for two consecutive growing seasons. Each practice was applied in Apr. 2006 at four levels. Sand was applied directly onto the vines at four depths: control (0 cm), light (1.5 cm), moderate (3.0 cm), or heavy (4.5 cm); pruning was conducted at four severities with a commercial pruner: control (not pruned), light (one pass with the pruner), moderate (two passes), and heavy (three passes). Pruning levels had no effect on upright density over the two seasons, but the heavy sanding treatment decreased the number of uprights per unit area. For the first season only, light penetration to soil level increased linearly as severity increased for pruning and sanding. The number of reproductive uprights relative to total uprights decreased in the first year as severity increased for both practices. This effect continued in the second year for sanding treatments. Cumulative yield and net returns were higher in light severity treatments compared to those in the moderate and heavy treatments. Moderate and heavy sanding treatments were associated with lower yields and net returns than those for the untreated controls.
Laura K. Hunsberger, Wesley R. Autio, Carolyn J. DeMoranville, and Hilary A. Sandler
Over a 2-year period, 11 cranberry (Vaccinium macrocarpon) farms in southeastern Massachusetts were selected to evaluate mechanical removal of swamp dodder (Cuscuta gronovii) with a conventional hand-held bamboo rake. This technique consisted of breaking and removing large strands of the parasite that connected host plants; embedded and encircled portions of the parasite were not removed. Differences in dodder biomass, cranberry yield, and berry weight were determined in plots that received zero, one, or two weed-removal events. Removing dodder one time per season reduced percentage of weed cover by more than 74% in both years. Impacts on dodder fresh and dry weight were not as discernible. Removal initially decreased dodder biomass, which remained 20% to 40% lower than the baseline values, but removal treatments did not differ statistically from the control. No additional benefits were obtained by removing the weed cover more than once. Biomass per berry was not affected by mechanical weed removal and fruit of marketable size were produced in the treated area. Substantial yield loss was largely attributable to the dodder infestations, but multiple removals may eventually reduce yield to levels below those associated with infestations alone.
Katherine M. Ghantous, Hilary A. Sandler, Wesley R. Autio, and Peter Jeranyama
Damage and recovery responses of four cranberry varieties (‘Mullica Queen’, ‘Crimson Queen’, ‘Stevens’, and ‘Howes’) to handheld propane flame cultivation (FC) torches were evaluated. All combinations of four levels of exposure duration of three FC torches (open flame 0, 3, 6, and 9 seconds), infrared (IR) and IR with a 4.5-cm metal spike (0, 15, 30, and 45 seconds), were tested on rooted cranberry uprights (vertical stems) planted in clay pots. Pots were subjected to a single treatment from one FC torch at one exposure duration; a glyphosate wipe was also included as a treated control (industry standard). Treatments were replicated five times. All cranberry plants were damaged by all levels of exposure duration as evident by visual damage ratings, reduced net cumulative stem lengths, reduced number of uprights, and reduced proportion of reproductive uprights when compared with untreated plants. All cranberry plants treated with glyphosate had total mortality; all cranberry plants from all varieties treated with FC survived, and all had net positive stem growth in the year after treatment except for ‘Stevens’ treated with open flame and IR with spike. The non-fatal response of cranberry to FC indicates that FC will cause less damage than glyphosate to cranberry plants that are incidentally exposed during spot treatment of weeds and thus could be integrated into weed control in certain situations, including organic farming.