bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Soil Type and Nitrogen Rate on Growth of Annual and Perennial Landscape Plants in Florida
Authors: Moore Kimberly A. , Shober Amy L. , Hasing Gitta , Wiese Christine , West Nancy G.
Published: December 2018

Previous research indicated that acceptable quality annual and perennial plant species can be grown in the landscape with low nitrogen (N) inputs. However, information on the impact of soil conditions and N use by ornamental plants grown in central Florida is lacking in the literature. Our objective was to evaluate plant growth and quality response of eight warm-season annuals, seven cool-season annuals, and four herbaceous perennial species to a range of N fertilizer rates when plants were grown in landscape beds containing native field soil or subsoil fill. A slow-release N source (42N–0P–0K) was applied every 12 weeks at annual N rates of 3, 5, or 7 lb/1000 ft2 for a period of 18 weeks (annual species) or 1, 3, or 5 lb/1000 ft2 for a period of 54 weeks (perennial species). Plants were evaluated for aesthetic quality every 6 weeks and shoot dry weight was measured at completion of the experiment. Dry weight production and aesthetic quality of most species evaluated was unaffected by N rate. For several species, shoot dry weight was higher when planted in the field plots containing native soil [alyssum (Lobularia maritima) ‘Bada Bing White’ wax begonia (Begonia ×semperflorens-cultorum), dahlberg daisy (Thymophylla tenuiloba), ‘Survivor Hot Pink’ geranium (Pelargonium ×hortorum), gomphrena (Gomphrena globosa), ‘Blue Puffs Improved’ (‘Blue Danube’) ageratum (Ageratum houstonianum), blanket flower (Gaillardia pulchella), goldenrod (Solidago chapmanii), ‘Mystic Spires’ salvia (Salvia longispicata ×farinacea)]. Quality response to soil condition was mixed over the course of the study. Several species performed as well (or better) in the field as when planted in the subsoil fill soils. These results illustrate that some landscape plant species are able to survive and thrive under various soil and fertility conditions. These “tougher” species may be good choices for installation in landscapes with marginal native soils or disturbed urban landscape soils.
Year-round Greenhouse Production of Cut Sunflowers in the Rocky Mountain West
Authors: Garfinkel Andrea R. , Panter Karen L.
Published: December 2018

The objective of this study was to determine the potential for year-round greenhouse production of specialty cut sunflowers (Helianthus annuus) in Wyoming. Over a 14-month period, we produced cut sunflowers in a nontraditional, transplant-based, potted method using natural light intensity and daylength conditions in Laramie, WY. Three cultivars of annual sunflowers, Dafna, ProCut Bicolor, and Sunbright Supreme, were grown from seeds sown at 2-week intervals starting on 16 Nov. 2011. Each planting consisted of four replications of four plants each. Seedlings were transplanted into 550-mL square plastic pots 15 days after sowing and were placed on greenhouse benches in blocks according to sow date. Flowers were cut at soil level when ray florets opened. Data collected included days to harvest and stem length for each stem. Results indicated significant cultivar by sow date interactions for days to harvest and stem lengths, indicating the importance of cultivar selection. Mean days to harvest ranged from 57 days (‘Sunbright Supreme’) to 103 days (‘ProCut Bicolor’). Mean stem lengths ranged from 43 cm (‘Dafna’) to 153 cm (‘Sunbright Supreme’). Overall, the results of this study show potential for year-round production of cut sunflowers and can help guide producers in the Rocky Mountain west to choose cultivars that best fit the needs of their business and market demand.
An Interactive Economic Decision Support Tool for Risk and Return Analysis of Organic Apple Production
Authors: Rodriguez Hector German , Popp Jennie , Rom Curt , Friedrich Heather , McAfee Jason
Published: December 2018

Numerous apple (Malus ×domestica) research experiments have shown that organic apples can be both profitable and sustainable, especially in the Pacific northwestern United States. However, there is limited published research on the profitability of organic apple orchards in the southern U.S. region. Surveys of southern U.S. stakeholders have indicated that great opportunities exist for markets of both fresh and processed fruit, but significant challenges still exist. These challenges include a lack of information available on the economic impacts of different organic production practices and the potential returns available from organic production. In response to these challenges, we developed a user-friendly interactive economic decision support tool using spreadsheet software to simulate organic apple production in Arkansas and across the southern United States. The purpose of this interactive economic decision support tool is 2-fold: 1) to assist producers in the evaluation of costs, returns, and risks associated with their organic apple orchard and 2) to assess changes to cost, return, and risk as expected costs, prices, and/or yields change. The production budget components of the interactive economic decision support tool estimate variable and fixed costs, gross revenues, and net returns for 18 years of production. In addition, this interactive economic decision support tool provides economic analyses regarding: 1) the operation’s breakeven (price and yield) points, 2) sensitivity analyses or “what if” scenarios related to changes in costs and returns, and 3) risk assessment by calculating the probability of obtaining a positive net present value (NPV) over the life of the organic apple orchard. This manuscript describes the development of this interactive economic decision support tool and provides an example of how it works.
Plant Growth Regulator Drenches Suppress Foliage and Inflorescence Height of ‘Leia’ Pineapple Lily
Authors: Carlson Alicain S. , Dole John M. , Whipker Brian E.
Published: December 2018

Plant growth regulators (PGRs) are used to control excessive plant growth in potted crops to improve quality and compactness for shipping and display. Pineapple lily (Eucomis sp.), a recent introduction to the potted crop market, can have excessive foliage growth and inflorescence height making the use of PGRs desirable. Bulbs of ‘Leia’ pineapple lily were forced in the greenhouse and drenched at leaf whorl emergence with three PGRs at five different concentrations: 1) flurprimidol (0.25, 0.5, 1.0, 2.0, and 4.0 mg per 6.5-inch pot), 2) uniconazole (0.25, 0.5, 1.0, 2.0, and 4.0 mg/pot), or 3) paclobutrazol (0.5, 1.0, 2.0, 4.0 and 8.0 mg/pot) and an untreated control. As concentration increased, days to anthesis increased and foliage height decreased for each PGR. Paclobutrazol (4.0 and 8.0 mg/pot), uniconazole (4.0 mg/pot), and flurprimidol (2.0 and 4.0 mg/pot) treatments resulted in excessive stunting with none of the plants being marketable. Flurprimidol had the greatest influence on plant growth among all the PGRs. Acceptable concentrations for each PGR are paclobutrazol at 0.5 to 2.0 mg/pot, uniconazole at 0.25 to 2.0 mg/pot, and flurprimidol at 0.5 to 1.0 mg/pot based on percentage of marketable plants and foliage and inflorescence height suppression without excessively increasing the number of days to anthesis.
Effects of Home Value, Home Age, and Lot Size on Lawn-watering Perceptions and Behaviors of Residential Homeowners
Authors: Bremer Dale J. , Keeley Steven J. , Jager Abigail
Published: December 2018

Urbanization is increasing the land area covered with turfgrasses, which may affect water quantity and quality. Our objective was to understand lawn-watering habits of homeowners in Olathe and Wichita, KS, based on home value, home age, and lot size. Surveys were mailed to 9992 homeowners in Olathe and 15,534 in Wichita, with a return rate of 12%. Owners of more expensive and/or newer homes were more likely to water frequently, water on a routine schedule, feel it was important to have a green lawn, have an in-ground sprinkler system, and sweep or blow grass clippings and lawn care products off impervious surfaces. Owners of less expensive and/or older homes were more likely to never water or water infrequently, water based on the lawn’s appearance rather than on a routine schedule, consider it less important to have a green lawn; not have an in-ground sprinkler system, and leave grass clippings and lawn care products on impervious surfaces rather than blowing them off. A small percentage of homeowners who swept or blew clippings and/or lawn-care products did so into streets/storm drains. Owners of less expensive and/or older homes were somewhat more likely to engage in this practice. Educational efforts to improve lawn water conservation should be concentrated on homeowners in more expensive and/or newer homes because they water more frequently and routinely. Efforts to protect surface water quality should include homeowners of less expensive and/or older homes.
Potential of Honeybee Brood Pheromone to Enhance Foraging and Yield in Hybrid Carrot Seed
Authors: Sagili Ramesh R. , Breece Carolyn R. , Simmons Rhonda , Borden John H.
Published: December 2018

Honeybee (Apis mellifera) brood pheromone is a blend of 10 fatty acid esters that stimulates worker pollen foraging, protein biosynthesis in the brood food-producing glands of nurse bees and queen oviposition. In separate experiments conducted in central Oregon, we tested the hypotheses that treatment of honeybee colonies with brood pheromone would stimulate increased bee foraging in hybrid carrot (Daucus carota) seed fields, and that in turn would result in increased seed yield. For both experiments, in each replicate, all honeybee colonies placed at one field were treated with brood pheromone, and those in a control field were not treated with brood pheromone. A total of 123,720 bee visits to flowers was recorded. For both sexes of flower, there were significantly more bee visits in fields in which colonies were treated with brood pheromone than in control fields (P < 0.05). There was also a significant preference for male flowers over female flowers (P < 0.05) by bees in the fields where colonies received brood pheromone when compared with control fields. Mean yields in fields pollinated by colonies treated with brood pheromone and those that were not treated with brood pheromone were 325.2 and 280.8 kg·ha−1, respectively. Mean percentage yield was significantly higher in fields where honeybee colonies received brood pheromone when compared with control fields that had colonies without brood pheromone (P < 0.01). Our results suggest that brood pheromone has the potential to increase honeybee foraging and seed yield in hybrid carrot seed crop.
An Assessment of Organic Apple Production in Kentucky
Authors: Williams Mark A. , Strang John G. , Bessin Ricardo T. , Law Derek , Scott Delia , Wilson Neil , Witt Sarah , Archbold Douglas D.
Published: December 2018

Although the interest in and production acreage of organic fruit and vegetables has grown in recent years, there are questions about the viability of perennial crops such as apple (Malus ×domestica) in an organic system in Kentucky because of the long, hot, and humid growing season. Thus, the objective of this project was to assess the severity of the challenges to organic apple production in Kentucky. A high-density, organic apple orchard was established in 2007 in the University of Kentucky Horticultural Research Farm in Lexington. The orchard of apple scab (Venturia inaequalis)–resistant ‘Redfree’, ‘Crimson Crisp’, and ‘Enterprise’ trees on ‘Budagovsky 9’ (B.9) rootstock, trained in a vertical axis system, was managed using organically certified techniques and materials for disease and insect control since its inception. Tree growth, tree and fruit injury from insect pests and diseases, and yield over the period 2011–13 were studied. Periodic, shallow cultivation kept the ground beneath the trees free of vegetation once the lower limbs were pulled up and away from the path of the equipment. Vole (Microtus sp.) damage was a continuing problem despite the use of trunk guards and cultivation to remove habitat around the trees. Total fruit yield ranged from 1.2 to 8.1 kg/tree across years and cultivars, with the marketable proportion of the total yield averaging 68% for Redfree and 43% for Crimson Crisp and Enterprise over the 3-year period. The unmarketable fruit exhibited a high incidence of plum curculio (Conotrachelus nenuphar) damage, with generally less damage from codling moth (Cydia pomonella) and sooty blotch (Glosodes pomigena)/flyspeck (Schizathyrium pomi). In addition, in two of the three seasons, ‘Crimson Crisp’ and ‘Enterprise’, which were harvested at later calendar dates then ‘Redfree’, had significant levels of powdery mildew (Podosphaera leucotricha) injury, ‘Enterprise’ had significantly greater bitter rot (Glomerella cingulata), and ‘Crimson Crisp’ showed fruit and foliar damage from cedar apple rust (Gymnosporangium juniperi-virginianae). Because ‘Redfree’ was the only cultivar with an acceptable marketable proportion of the fruit crop, the use of early ripening disease-resistant apple cultivars may have the greatest potential for successful organic apple production in Kentucky and the surrounding region.
The Effects of Plastic Mulch Systems on Soil Temperature and Moisture in Central Ontario
Authors: Snyder Kayla , Grant Amanda , Murray Christopher , Wolff Bryon
Published: December 2018

The impact of polyolefin-based agricultural mulch films (including clear, black, and white-on-black films) on soil temperature and moisture content was studied, using a bare plot as a control, over a 4-month period in central Ontario, Canada. Data indicate a negative correlation between the change in soil temperature under the films relative to bare soil and the absolute value of bare soil temperature. Additionally, a negative correlation between the effect of films on soil moisture and the moisture level of bare soil was indicated. All mulch films demonstrated qualitatively similar ability to insulate the soil from extremes in both temperature and moisture, suggesting a potentially reduced need for irrigation and protecting against early frost, high temperatures, overwatering, and drought.
Seasonal Water Use of Southern Highbush Blueberry Plants in a Subtropical Climate
Authors: Williamson Jeffrey G. , Mejia Luis , Ferguson Bradley , Miller Paul , Haman Dorota Z.
Published: December 2018

Nonweighing drainage lysimeters were used to measure seasonal water use of mature ‘Emerald’ southern highbush blueberry (SHB; Vaccinium corymbosum interspecific hybrid) plants grown in pine bark beds and in pine bark amended soil in north central Florida. In the absence of rain, irrigation was applied daily with microsprinklers at ≈120% to 175% of reference evapotranspiration as either single or split applications. Leachate was collected and its volume determined from each lysimeter at 6- to 10-day intervals throughout the study. Water use, expressed as L/plant, was calculated as the difference between the amount of irrigation/rain added to lysimeters and the amount of leachate collected from lysimeters during each measurement period. Average daily water use was calculated for monthly intervals beginning in Apr. 2010 and ending in Sept. 2012. Water use increased rapidly during spring through the final stages of fruit ripening and harvest (May) with peak water use occurring during mid to late summer (July, August, and September). Plants grown in pine bark beds used more water than plants in pine bark amended soil during Apr., May, and Dec. 2010, Feb. 2011, and Mar. 2012, but there were no differences during the periods of highest water use. No differences in water use were observed between single or split-application irrigation treatments. Monthly averages for daily water use during the 30-month period ranged from ≈1.75 L/plant in January to ≈8.0 L/plant in mid to late summer. Mean monthly crop coefficient values during the 30-month period ranged from 0.44 in February to 0.86 in September. Canopy volume, yield, and mean berry weight were unaffected by soil or irrigation treatments.
Auxin Type, Auxin Concentration, and Air and Substrate Temperature Difference Play Key Roles in the Rooting of Juvenile Hardwood Pecan Cuttings
Authors: Zhang Ji-Yu , Guo Zhong-Ren , Zhang Rui , Li Yong-Rong , Cao Lin , Liang You-Wang , Huang Li-Bin
Published: December 2018

This study examined the ability to vegetatively propagate 1-year-old pecan (Carya illinoinensis) through the rooting of hardwood cuttings. Cuttings were treated with varying concentrations of different auxins and different combinations of media and ambient temperatures. Under different temperature conditions, all auxin treatments induced the rooting of cuttings but did not promote sprouting. The effectiveness of the induction of adventitious roots was as follows: 1-naphthalene acetic acid (NAA) > indole 3-butyric acid > indole 3-acetic acid. The base of the parent shoot treated by NAA at a concentration of 0.09%, planted in substrate with bottom heat was the most effective, with 82% rooting, 8.3 roots/cutting and root lengths of 7.3 cm. These findings suggested that auxin and substrate/air temperature differences are both indispensable in the process of adventitious roots formation in pecan. This study revealed that the propagation of hardwood cuttings derived from branches of 1-year-old pecan is possible.
Using Google Maps Web-application to Create Virtual Plant Maps for Use as an Online Study Tool in Plant Identification Courses
Authors: Wilson Matthew S. , Miller Chad T.
Published: December 2018

Virtual plant maps were developed using a web-application for plant identification courses with the goal of providing an additional study resource to students. Each map plots the plants covered for the given weekly plant list, providing photographs of specimens, correct nomenclature, along with additional identification and cultural information. The virtual plant maps provide students an opportunity to review and revisit plants covered in lecture and laboratory sections on their own and at their convenience. An additional advantage of the virtual plant maps is that they can be easily created using a free web-application via any Internet browser, without the need for rigorous understanding of software and webpage design.
Foliar Applied Abscisic Acid Increases ‘Chardonnay’ Grapevine Bud Freezing Tolerance during Autumn Cold Acclimation
Authors: Dami Imed E. , Li Shouxin , Bowen Patricia A. , Bogdanoff Carl P. , Shellie Krista C. , Willwerth Jim
Published: December 2018

Economic loss due to cold weather events is a major constraint to winegrape (Vitis vinifera) production and wine-related industries where extreme and/or fluctuating winter temperatures induce injury and require remedial retraining and replanting increases production costs and lowers yield and fruit quality. The purpose of this study was to determine whether a foliar application of abscisic acid (ABA) could increase the freezing tolerance (FT) of field-grown, ‘Chardonnay’ winegrape and whether its effectiveness can be influenced by the phenological timing of the application. Mature ‘Chardonnay’ grapevines were treated with a foliar application of ABA at a concentration of 500 mg·L−1 at vine phenological stages corresponding to 50% véraison, postvéraison, and postharvest. Results from field trial sites located in four distinct winegrape production regions in the United States (Idaho and Ohio) and Canada (British Columbia and Ontario) showed that foliar application of ABA increased bud FT, primarily during autumn cold acclimation. Foliar ABA application had no consistent influence on bud FT in midwinter or during spring deacclimation, or on percent budburst in spring. Vine phenological stage at the time of ABA foliar application influenced ABA effectiveness, although results were inconsistent among locations. At most locations, applications made at véraison or postvéraison were more effective than applications made postharvest. No phytotoxic response or adverse changes in yield or berry composition were detected in response to ABA application. The consistent increase in bud FT during autumn cold acclimation observed at all trial locations in this study indicates that foliar ABA, applied at véraison or postvéraison, can reduce the risk of economic loss due to cold injury in production regions with frequent early autumn cold weather events.
Portable Frost-protection Misting System: Trial on Tomato and Sweet Orange Crops
Authors: McCartney Lucas , Lefsrud Mark
Published: December 2018

During the North American crop-growing season, although daytime temperatures may remain well above freezing point, nighttime temperatures can easily drop below 0 °C for a few hours. The effects of frost are felt in small operations, such as residential gardens, or in specific areas of a larger operation. Various large-scale measures exist for crop frost protection but they are neither portable nor flexible. A fully automated portable frost-protection misting system that makes use of the latent heat of fusion of water was developed and tested on tomato (Solanum lycopersicum) and sweet orange (Citrus sinensis) at the Macdonald Campus of McGill University (Saint-Anne-de-Bellevue, QC, Canada). The water tank stores up to 20 gal of pressurized water and detachable auxiliary air tanks provide additional line pressure. The device is lightweight, portable and provides flexible, overhead water misting for two 25-ft rows of crops. It activates autonomously using a thermostat, battery pack, and solenoid valve, and the outlet pressure is regulated using a pressure regulator. It is easily installed and dismantled for expedient relocation and the dynamic system of tubing and nozzles can be modified as required. The system was tested in subzero ambient air temperature ranging from −7.1 to 0 °C. During misting, the flesh of the targeted tomato fruit remained, on average, 3.1 and 3.6 °C warmer than ambient temperatures. The use of the system is currently limited by the infrequent formation of ice on the misting nozzles and in the water lines due drastic drops in temperature.
Plant Factors for Irrigating Mixed Turfgrass and Shrub Landscapes in a Humid Environment
Authors: Pannkuk Tim R.
Published: December 2018

Landscape water conservation methods and techniques contribute to managing water resources. Use of reference evapotranspiration (ETo) data and landscape coefficients is one method that needs further development. Local ETo data and actual plant water use were used to calculate plant factors (PFs) for three model landscapes composed of mixtures of turfgrass and shrubs. Model landscapes using a sandy loam soil included st. augustinegrass (Stenotaphrum secundatum), privet (Ligustrum japonicum), dwarf burford holly (Ilex cornuta ‘Burfordii Nana’), and dwarf yaupon holly (Ilex vomitoria ‘Nana’) at three ratios of turfgrass to shrub vegetative cover: 80:20, 50:50, and 20:80. Soil was placed into inground lysimeters in a complete randomized block design with soil moisture sensors and a drainage system. Lysimeters were irrigated with a sprinkler system, and water was applied at a rate of 100% replacement of ETo minus precipitation. Lysimeter soil leachate was collected from the drainage system and quantified. After 2 years, the PF of 20:80 and 50:50 turfgrass/shrub combination were greater than the PF of the 80:20 combination. Plant factors for the 80:20, 50:50, and 20:80 turfgrass:shrub combinations were 0.68, 0.97, and 1.01, respectively. There were no seasonal differences in PFs. Total growing season leachate depth over 2 years was 63.4, 30.7, and 12.6 mm for 80:20, 50:50, and 20:80, respectively. Further work on PFs should include other plant combinations, and evaluation in other climatic zones.
Stimulation of Lateral Branching of Red Firespike Using Dikegulac Sodium, Benzyladenine, and Pinching
Authors: Rezazadeh Amir , Harkess Richard L. , Bi Guihong
Published: December 2018

Red firespike (Odontonema strictum) is an ornamental shrub with potential for use as a flowering potted plant due to its dark green foliage and attractive red flower spikes. To stimulate branching and improve quality of red firespike, foliar spray applications of dikegulac sodium (DS) and benzyladenine (BA) and hand pinching were evaluated across two seasons (Spring and Summer 2014). There were three pinching treatments: one, two, or three pinches. Plant growth regulators (PGRs) were applied at 400, 800, 1600, or 2400 ppm DS or 600, 1000, 1250, or 1750 ppm BA. Both studies included an untreated control. Red firespike treated with all concentrations of BA and 1600 and 2400 ppm DS had increased branching compared with the control, except 1000 ppm BA in Expt. 1. Pinching did not affect the number of branches. Dikegulac sodium at 1600 and 2400 ppm and all concentrations of BA resulted in shorter plants than the control. Phytotoxicity was observed in plants treated with 1600 or 2400 ppm DS. In both experiments, DS at 1600 and 2400 ppm had the least plant dry weight compared with the control. Treatment with BA at 1750 ppm resulted in greatest leaf area compared with control. Dikegulac sodium at 800 ppm increased the number of flowers compared with control. Pinching and BA did not affect number of inflorescences. All concentrations of BA and DS delayed flowering, except 1000 ppm BA. Plants treated with 800, 1600, and 2400 ppm DS had shorter inflorescences compared with control plants. Benzyladenine decreased the length of the inflorescence at high concentrations, 1250 and 1750 ppm. Pinching treatments did not affect inflorescence length.
Importance of Hand Hygiene during the Harvesting of Strawberries
Authors: Shaw Angela , Svoboda Amanda , Jie Beatrice , Daraba Aura , Nonnecke Gail
Published: December 2018

Foodborne outbreaks linked to poor hygiene indicate a need for education on the importance of hand hygiene during harvesting of fruit. This study simulated two potential scenarios (laboratory and field) that would lead to the transfer of Escherichia coli O157:H7 from hands to strawberries (Fragaria ×ananassa), harvesters, and field plants. The potential of direct transfer of E. coli O157:H7 from contaminated “pig skin” hands to strawberries was shown in Scenario 1. The potential of E. coli O157:H7 being transferred from contaminated hands to strawberries during harvesting was shown in all treatments up to the 100th strawberry tested with a transfer rate of 71% (1 berry) to 45% (100 berries) of E. coli. Scenario 2 mimicked the “bacteria” transfer from the worker’s contaminated hands to the workers’ clothing and to the field with the use of glowing lotion. It was shown that contaminated hands can transfer “bacteria” to the worker’s clothing, shoes, the picked strawberries, and the strawberry plants, weeds and straw mulch within the field (average spread of 50.25 ft from starting point). The transfer rate varied from worker to worker. Hand hygiene and proper worker training are essential for food-safe harvesting to avoid foodborne outbreak events.
A Review of Organic Lawn Care Practices and Policies in North America and the Implications of Lawn Plant Diversity and Insect Pest Management
Authors: Marshall Sam , Orr David , Bradley Lucy , Moorman Christopher
Published: December 2018

There are ≈40 million acres of turfgrass lawns throughout the United States, most of which are managed under chemical-intensive pest and fertilizer programs. “Organic lawn care” is being adopted more widely; however, unlike the formally defined policies and regulations that govern organic agriculture, the label organic lawn management has not been formally defined and is used to describe a variety of practices. Neighborhoods, cities, states, and provinces across North America are adopting policies regulating the use of pesticides and fertilizers in the landscape. In addition, a small but growing number of public institutions and individual consumers are successfully adopting alternative lawn care methods, including organic lawn care. Although perceived as environmentally friendly, the effects of organic management on insect diversity and pest management remain understudied. Organic lawn management may lead to increased lawn plant diversity, which in agroecosystems has enhanced ecological services provided by beneficial insect species. Effects of vegetative diversity on lawn pest management are less clear. Vegetative complexity and increased plant diversity in urban landscapes may enhance insect predator efficacy. The diversity of predatory insects varies between turfgrass varieties in response to prey populations. Mortality of insectivorous and granivorous ground beetles (Carabidae) while not directly impacted by pest management programs in turfgrass may be indirectly impacted by a reduction in the prevalence of plant species that provide alternative food resources. Previous studies have focused on herbivorous insects as well as predatory and parasitic insects that feed on them. Future studies should assess how lawn plant diversity resulting from organic management practices might impact insect communities in turfgrass.
Nutrient Assimilation in Southern Highbush Blueberry and Implications for the Field
Authors: Darnell Rebecca L. , Casamali Bruno , Williamson Jeffrey G.
Published: December 2018

Successful blueberry (Vaccinium sp.) cultivation typically requires soils with low pH, high organic matter, readily available iron, and nitrogen (N) in the ammonium form. Growth of blueberry on typical mineral soils (higher pH, low organic matter) is reduced. Although soil pH effects on nutrient availability and uptake are known, it is unclear if the requirement for low soil pH in blueberry production is due to effects on nutrient availability/uptake or is a more direct effect of rhizosphere pH on root function. In addition, it is unclear if the requirement for high organic matter (soil amendments) is related directly to nutrient availability/uptake. Several studies have examined the use of rootstocks to increase soil adaptation of blueberry and some of these rootstocks have been found to increase plant vigor and yield. In particular, we have investigated whether sparkleberry (Vaccinium arboreum)—a wild blueberry species that is adapted to high pH and low organic matter soils—could be used as a rootstock for commercial production of blueberry on mineral soils. Our work indicates that both nitrate (NO3−) and iron (Fe) uptake and assimilation are greater in sparkleberry compared with southern highbush blueberry [SHB (Vaccinium corymbosum interspecific hybrid)]. This is correlated with increased activity of nitrate reductase (NR) and iron chelate reductase, the rate limiting enzymes for NO3− and Fe acquisition, respectively. Field studies comparing growth and yield of own-rooted vs. grafted ‘Meadowlark’ and ‘Farthing’ SHB in amended vs. nonamended soils are ongoing. In general, own-rooted plants on amended soils exhibit greater growth than own-rooted on nonamended soils, while grafted plants in either soil system exhibit intermediate growth. Yields generally followed this pattern. Our preliminary results suggest that tolerance of SHB to mineral soils is greater when plants are grafted onto sparkleberry than when grown on their own roots. However, growth and yield of grafted plants grown under mineral soil conditions may not equal or exceed that of own-rooted plants grown under optimum soil conditions, at least in the first years after field planting. Longer term studies are necessary to fully evaluate the potential of using sparkleberry and other blueberry species as rootstocks for SHB and northern highbush blueberry (V. corymbosum).
Nutrient Requirements, Leaf Tissue Standards, and New Options for Fertigation of Northern Highbush Blueberry
Authors: Bryla David R. , Strik Bernadine C.
Published: December 2018

Northern highbush blueberry (Vaccinium corymbosum) is well adapted to acidic soils with low nutrient availability, but often requires regular applications of nitrogen (N) and other nutrients for profitable production. Typically, nutrients accumulate in the plant tissues following the same pattern as dry matter and are lost or removed by leaf senescence, pruning, fruit harvest, and root turnover. Leaf tissue testing is a useful tool for monitoring nutrient requirements in northern highbush blueberry, and standards for analysis have been updated for Oregon. Until recently, most commercial plantings of blueberry (Vaccinium sp.) were fertilized using granular fertilizers. However, many new fields are irrigated by drip and fertigated using liquid fertilizers. Suitable sources of liquid N fertilizer for blueberry include ammonium sulfate, ammonium thiosulfate, ammonium phosphate, urea, and urea sulfuric acid. Several growers are also applying humic acids to help improve root growth and are injecting sulfuric acid to reduce carbonates and bicarbonates in the irrigation water. Although only a single line of drip tubing is needed for adequate irrigation of northern highbush blueberry, two lines are often used to encourage a larger root system. The lines are often installed near the base of the plants initially and then repositioned 6–12 inches away once the root system develops. For better efficiency, N should be applied frequently by fertigation (e.g., weekly), beginning at budbreak, but discontinued at least 2 months before the end of the growing season. Applying N in late summer reduces flower bud development in northern highbush blueberry and may lead to late flushes of shoot growth vulnerable to freeze damage. The recommended N rates are higher for fertigation than for granular fertilizers during the first 2 years after planting but are similar to granular rates in the following years. More work is needed to develop fertigation programs for other nutrients and soil supplements in northern highbush blueberry.
Cranberry Nutrient Management in Southeastern Massachusetts: Balancing Crop Production Needs and Water Quality
Authors: DeMoranville Carolyn
Published: December 2018

The american cranberry (Vaccinium macrocarpon) is a wetland plant native to North America. The plant is adapted to sandy, nutrient-poor, low pH soils and thus, like blueberry (Vaccinium sp.), its nutritional requirements are low compared with many other perennial fruit crops. Research conducted over the past 30 years has defined the annual requirements for nitrogen [N (20–60 lb/acre)], phosphorus [P (<20 lb/acre)], and potassium (40–120 lb/acre) based on tissue testing, plant growth demands, potential for remobilization, and determination of removal in the crop. These three nutrient elements are those most commonly applied to the crop in fertilizers. However, much of the work on nutrient rate requirements was conducted on native cultivars and there is an expectation that requirements of newer hybrid cultivars are greater. In Massachusetts, cranberries are grown in coastal watersheds and often depend on small lakes as their water source for irrigation, harvest, and winter flooding. Since cranberry production is heavily dependent on water use, the interaction of nutrient management and water management has become a primary focus area for research and extension, particularly for N and P, the nutrient elements most frequently associated with environmental pollution. Recent preliminary research examining cranberry farms with varied configurations (e.g., water passes through the bog and exits via a long channel, water recirculates back into the supply water body) has indicated that the cranberry bogs may act as either a source or sink for N depending on configuration and management activities. In a study of cranberry farms where P use was reduced to an average of <10 lb/acre, P concentration in harvest flood water declined by as much as 85% while crop production was sustained. Site variation in output of N and P in cranberry drainage and flood waters indicates the need for further research into the variables that control these processes, including soil types, site hydrology, nutrient application rates and forms, and water-management activities.
Evaluating Florida Homeowner Response to Smart Irrigation Controllers
Authors: Morera Maria C. , Monaghan Paul F. , Dukes Michael D. , Wells Ondine , Davis Stacia L.
Published: December 2018

Smart irrigation controllers are capable of substantially decreasing landscape water applications under residential high water-use conditions in Florida. Their implementation has been incentivized by governmental agencies and water utilities in an effort to reduce public-supply water demand and conserve water resources. However, the bulk of the research on smart controllers for urban landscapes has focused on performance dimensions. To successfully promote them, feedback from end-users is critical. This paper provides an evaluation of homeowner response to evapotranspiration (ET)-based and soil moisture sensor (SMS)-based smart controllers installed as part of a pilot project conducted in Orange County, FL. The objectives of the study were to collect demographic information, assess conservation attitudes and irrigation system knowledge, and gather feedback on the use of smart controllers from the pilot project’s residential cooperators. Data were collected through an online survey and analyzed using relative frequency distributions, text analysis, independent means t tests, and logistic regression. Results indicated that a majority of survey participants were satisfied with their controllers and planned to continue using them. Both ET and SMS controllers were consistently praised for saving money and irrigating efficiently. However, the likelihood that participants would continue using their controllers after the completion of the project was only significantly predicted by their levels of technical knowledge regarding the workings of the devices and whether they had experienced any challenges operating them. Efforts to promote both initial and long-term adoption may be most effective by emphasizing the economic benefits of investing in smart irrigation controllers and by disseminating best management practices that facilitate their understanding and successful operation.
Effect of Uniconazole on the Control of Plant Height and Fruit Yield of Potted Tomato, Pepper, and Eggplant
Authors: Villavicencio Lucia E. , Bethke James A. , Corkidi Lea
Published: December 2018

Two experiments were conducted to evaluate the effect of the plant regulator uniconazole on plant height, flowering, and fruit yield of vegetable transplants. In the first experiment, seedlings of tomato (Solanum lycopersicum ‘Early Girl’), pepper (Capsicum annuum ‘Jalapeno’), and eggplant (Solanum melongena ‘Millionaire’), were sprayed with water (untreated control) or with 2.5, 5, and 10 mg·L−1 of uniconazole. Five weeks after treatment (WAT), application of 2.5 mg·L−1 of uniconazole reduced the height of tomato by 17%, and of 5 and 10 mg·L−1, by 25%. The effect of 10 mg·L−1 of uniconazole on tomato plant height persisted until 13 WAT, but did not affect fruit yield. ‘Early Girl’ tomato plants treated with 10 mg·L−1 of uniconazole were still shorter than the untreated control at this time, but there were no significant differences in the number or weight of the fruit produced by the plants treated with 10 mg·L−1 of uniconazole, and the untreated controls. In contrast, as the rate of uniconazole increased, the height of ‘Jalapeno’ pepper and ‘Millionaire’ eggplant decreased. Application of uniconazole had no effect on the number of fruit produced by ‘Millionaire’ eggplant. However, treatment with 10 mg·L−1 of uniconazole reduced the number of fruit produced by pepper plants by 50%, and reduced the total weight of fruit produced by pepper and eggplant plants by 30% and 50%, respectively, compared with the untreated control. The second experiment analyzed the effects of 5, 8, and 10 mg·L−1 of uniconazole on two cultivars of tomato with different growth habit, Early Girl (determinate) and Sun Sugar (indeterminate). Application of all rates of uniconazole decreased plant height but not the final fruit yield of the two tomato cultivars.
Nonstructural Carbohydrate Concentrations in Dormant Grapevine Scionwood and Rootstock Impact Propagation Success and Vine Growth
Authors: Phillips Nathan , Reynolds Andrew , Di Profio Frederick
Published: December 2018

Objectives of this study were to quantify starch and soluble sugar concentrations in wine grape (Vitis sp.) scionwood and rootstock material, and to examine relationships between carbohydrate (CHO) metrics and both grafting success and shoot growth. CHOs of three wine grape scionwood cultivars [Merlot and Riesling (Vitis vinifera) and Vidal blanc (Vitis sp.)] harvested from four separate vineyards in the Niagara Peninsula in Ontario were analyzed for starch, total CHOs, total sugars, sucrose, monosaccharides (glucose, fructose), and oligosaccharides (raffinose, stachyose) to determine if CHO differences existed between scionwood cultivar and site, and whether these impacted propagation success when grafted to two different rootstocks [‘3309 Couderc’ (3309) and ‘101-14 Millardet et de Grasset’ (101-14) (V. riparia × V. rupestris)]. Differences in CHOs existed between vineyards for all cultivars, and their relationship with propagation success was most evident with ‘Vidal blanc’. Differences were also observed between sites for some cultivars in terms of grafting success and shoot length of grafted vines. Hot water treatment (HWT) of rootstock increased total sugars, glucose, fructose, and stachyose in 3309, and led to lower starch, total CHOs, and higher sucrose in 101-14 when measured immediately following HWT. At time of grafting, HWT 3309 had lower starch sucrose and raffinose, and higher glucose, fructose, and total sugars compared with non-HWT material, whereas HWT 101-14 contained lower total sugars, raffinose, and sucrose and higher stachyose and glucose. Stachyose, raffinose, sucrose, glucose, fructose, and total sugars in scionwood at time of grafting were correlated with propagation success. However, CHOs at time of scionwood collection in February did not correlate to successful propagation. Relationships between scion viability of all cultivars vs. stachyose and total sugars for both rootstocks suggested a possible relationship between these CHO metrics and propagation success. Differences likewise existed between propagation success on rootstocks 3309 and 101-14 on most occasions with 3309 displaying higher percent scion viability and shoot growth. This may be of particular importance in grafting difficult-to-propagate rootstock cultivars.
Survey of 575 Daylily Cultivars for Severity of Daylily Rust in a Southern Mississippi Landscape
Authors: Blythe Eugene K. , Pounders Cecil , Anderson Michael , Watts Earl , Watts Barbara
Published: December 2018

Daylily (Hemerocallis sp.) is a popular and widely planted herbaceous perennial in the landscape, with over 78,000 cultivars registered with the American Hemerocallis Society. Daylily performs well in full sun, heat, humidity, and periods of dry weather, and has generally been considered to be pest free. However, a rust disease (Puccinia hemerocallidis) was introduced in the United States on imported plants in 2000, quickly spreading to become a widespread problem on daylily in and beyond the southern United States. In Aug. 2013, 575 daylily cultivars (mostly newer hybrids) were surveyed for daylily rust in a large landscape planting that had not received any fungicide treatment during the 2013 growing season. Weather conditions during the growing season were favorable for daylily rust. Individual clumps were rated as 1 (no or little visual sign of infection), 2 (moderate infection), or 3 (severe infection). In this survey, 119 cultivars (21%) received a median rating of 1 or 1.5, 230 cultivars (40%) received a rating of 2, and 226 (39%) received a rating of 2.5 or 3. Most cultivars were represented by a single clump, and may thus be more susceptible to daylily rust than a single rating might indicate. Diploid cultivars were associated with lower daylily rust severity ratings than tetraploid cultivars.
Cotyledonary Axillary Shoot Control by Fatty Alcohol Application for Grafting Tomato
Authors: Eguchi Tomomi , Kubota Chieri
Published: December 2018

In tomato (Solanum lycopersicum), grafting position is recommended to be below rootstock cotyledons to avoid undesirable axillary shoots growing out from the cotyledons. In contrast, grafting above the rootstock cotyledons is desired to assure adequate distance between grafted union and soil line, only if there is no potential grow-out of axillary shoots from rootstock cotyledons. The objective of this preliminary study was to examine fatty alcohol application on cotyledonary axils of tomato seedlings to control undesirable axillary shoot extension from rootstock in tomato grafting. Solution containing various concentrations of a commercial fatty alcohol compound was applied to different growing stages of cotyledonary axillary shoots (nonextended buds or extended shoots) of tomato seedlings grown in a greenhouse. When fatty alcohol was applied directly to cotyledonary axillary buds, the seedlings were then pinched to force-induce the axillary shoot extension to assure the efficacy of the fatty alcohol treatment. High concentrations (10% and 15%) of fatty alcohol suppressed incidence of axillary shoot extension to less than 7% by killing buds. However, when applied to extended axillary shoots, application with 2% or higher concentrations of fatty alcohol caused plant collapse because excess fatty alcohol flowed down the stem and presumably damaged the root system. Therefore, we concluded that application of fatty alcohol to control cotyledonary axillary shoots of tomato rootstock could be possible only if fatty alcohol at effective concentration (10% to 15%) is applied exclusively to the target buds.
Optimal Nitrogen Concentration and Rapid Nutritional Diagnosis of Nitrogen Requirement for Container Production of Malabar Chestnut
Authors: Peng Yung-Liang , Liu Fang-Yin , Shen Rong-Show , Chang Yu-Sen
Published: December 2018

Nitrogen (N) is a major element required for crop cultivation and an important factor affecting plant growth and development. Malabar chestnut (Pachira macrocarpa) is an important ornamental potted plant crop whose N requirement has been studied, and a rapid monitoring method to manage N fertilization during its commercial production is yet to be established. Malabar chestnut seedlings were fertilized weekly with 0, 4, 8, 16, or 24 mm N. After 12 weeks, 16 mm N was found to yield the greatest plant growth such as plant height, number of nodes, and total leaf area. Measurements of chlorophyll meter readings, leaf chlorophyll concentration, leaf N concentration, and leaf dry weight all indicated that the optimal level of N fertilization was 16 mm N. A chlorophyll meter can be used to monitor nondestructively whether sufficient N has been supplied to support optimal plant growth. In this study, a chlorophyll meter reading of 46.1 corresponded with a critical leaf N concentration of 2.65%, defined as the leaf N concentration when the leaf dry weight was at 90% of saturation point. Additional N supplied beyond this critical level increased foliar chlorophyll content and improved the rate of net photosynthesis. Therefore, chlorophyll meter readings, which are convenient and nondestructive can serve as a reliable reference for commercial production in monitoring N requirement for optimum growth of malabar chestnut. Weekly fertilization of malabar chestnut with 16 mm N and maintaining leaf chlorophyll meter readings between 46.1 and 58.4 are recommended.