Container-grown Nursery Plants Research Articles

Review and Current Status of Systena frontalis (Coleoptera: Chrysomelidae): An Insect Pest Associated with Nursery Production Systems1

Abstract Systena frontalis (F.) (Coleoptera: Chrysomelidae) is an insect pest of nursery production systems throughout the Midwest, Southeast, and Northeast regions of the United States. The original scientific name was Galleruca frontalis F. before reclassification of the genus to Systena. There is minimal information in the scientific literature providing evidence that S. frontalis is native or an introduced species. In addition, the overwintering life stage is unknown. However, records indicate that S. frontalis is native to North America based on reports of this beetle being found in 5 provinces of Canada and 31 states in the United States. Records also indicate that the adult may be the overwintering life stage. Current management strategies implemented to reduce feeding damage caused by S. frontalis adults to container-grown nursery plants are associated with foliar spray applications of contact insecticides. However, applying contact insecticides to plant material in nursery production systems is labor intensive and not cost efficient. Application of systemic insecticides to the growing medium is a management strategy that nursery producers can use to reduce feeding damage caused by S. frontalis adults. Research demonstrates that the systemic insecticides dinotefuran and thiamethoxam protect container-grown nursery plants 45 d after application. Therefore, based on empirical, scientific-based research, applying systemic insecticides before S. frontalis adults are active provides practical and cost-effective plant protection from adult feeding damage during the growing season, thereby allowing nursery producers to grow, market, and sell container-grown nursery plants.

Residual Activity of Systemic Insecticides against Field-Collected Populations of Redheaded Flea Beetle (Coleoptera: Chrysomelidae), Systena frontalis, Adults under Laboratory and Greenhouse Conditions1

Abstract Systena frontalis (F.) is an insect pest of nursery production systems in the Midwest, Southeast, and Northeast regions of the United States. Adults feed on plant leaves and can reduce salability of container-grown nursery plants. Limited management options are available to protect plants from S. frontalis adult feeding damage. Insecticide spray applications to plant leaves are labor-intensive and not cost-efficient. Systemic insecticide applications to the growing medium may protect plants from S. frontalis adult feeding. In 2023, we conducted two laboratory and two greenhouse experiments to assess the residual activity of the systemic insecticides dinotefuran, thiamethoxam, and acephate against field-collected populations of S. frontalis adults. In the laboratory experiments, growing medium containing Itea virginica L. ‘Little Henry’ plants were treated with these three systemic insecticides. Twenty-five and 45 d after treatments were applied, leaves were collected and placed into petri dishes with a single S. frontalis adult. In the greenhouse experiments, Itea plants were placed into plastic observation cages. Eight S. frontalis adults were released into each cage with a single Itea plant. In the laboratory experiments 25 and 45 d after application of dinotefuran and thiamethoxam, the S. frontalis adults in the dishes with treated leaves had 66–90% mortality after 72 h. In the greenhouse experiments, dinotefuran and thiamethoxam protected Itea plants from S. frontalis adult feeding 45 d after application; 2.4 and 2.8 mm2 of leaf area were fed upon by S. frontalis adults. These results indicate that systemic insecticides can reduce feeding damage by S. frontalis adults on container-grown nursery plants.

Validating and Optimizing a Method for Detecting Phytophthora Species by Baiting Leachate from Arrays of Container Nursery Plants

In 2014, Phytophthora root rot was identified as a serious problem in nursery plants grown for habitat restoration in California. To support efforts to produce restoration nursery stock free of Phytophthora species, we developed a standardized leachate baiting method that can be conducted by nursery staff. Each plant in an array of up to 42 container-grown nursery plants is irrigated six times at 15-min intervals with a standardized water volume. Irrigation leachate is collected in a specialized vessel containing a green (unripe) pear bait. Test sensitivity was assessed using arrays of Phytophthora-free plants containing varying numbers of plants from which Phytophthora had previously been baited. The percentage of tests with Phytophthora detections increased as the proportion of infested plants in the array increased. In tests of individual inoculated plants, Phytophthora detection from a given plant varied over time, especially for less susceptible hosts. This variability likely limits test sensitivity in arrays with few infested containers. Direct probability and Monte Carlo simulation models showed that testing two to three arrays per block and 20 to 40 plants per array provided the greatest increases in detection probability for blocks of 200 to 1,000 plants in which 1 to 5% of the plants were infected. Random sampling had lower detection success than sampling biased to increase the odds of selecting infected plants. Results of extensive testing at a case study nursery were consistent with model predictions. The leachate baiting method has wide applicability for detecting and identifying Phytophthora species in nursery stock. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Evaluation of Systemic Insecticides in Protecting Container-Grown Nursery Plants from Damage Caused by Field-Collected Populations of Redheaded Flea Beetle, Systena frontalis (Coleoptera: Chrysomelidae), Adults

Abstract Systena frontalis (F.) is a major insect pest of nursery production systems in the Midwest, Northeast, and Southeast regions of the United States. Adults feed on plant leaves, which reduces salability of nursery-grown plants. There are limited options available to protect plants from S. frontalis adult feeding damage, and foliar insecticide applications are labor intensive. Systemic insecticides applied to the growing medium may protect plants from S. frontalis adult feeding. Consequently, in 2021 and 2022, we conducted two laboratory and two greenhouse experiments to determine if the systemic insecticides thiamethoxam, dinotefuran, cyantraniliprole, acephate, imidacloprid, and cyfluthrin + imidalcoprid protect plants from feeding by field-collected populations of S. frontalis adults. In the laboratory experiments, growing medium containing Itea plants was treated with the aforementioned systemic insecticides. Seven and 25 d after the treatments were applied, leaves were collected and placed into Petri dishes with a single S. frontalis adult. In the greenhouse experiments, Itea plants were placed into observation cages. Eight S. frontalis adults were released into each cage with an Itea plant. In the laboratory experiments, treatments associated with thiamethoxam and dinotefuran resulted in 100% mortality of S. frontalis adults after 72 h. In the greenhouse experiments, thiamethoxam, dinotefuran, and acephate protected plants from S. frontalis adult feeding 7 d after applying the systemic insecticide treatments. Therefore, systemic insecticides can mitigate feeding damage caused by S. frontalis adults on nursery-grown plants.

Measuring the Irrigation Requirement of Container-Grown Nursery Plants

Three factors determine the irrigation requirement for container-grown crops: evapotranspiration, capture factor, and distribution uniformity. This 4-page fact sheet describes how these factors can be measured so that irrigation requirements can be determined in the container nursery. Written by Jeff Million and Tom Yeager, and published by the UF Department of Environmental Horticulture, June 2012. ENH1197/EP458: Measuring the Sprinkler Irrigation Requirement of Container-Grown Nursery Plants (ufl.edu)

Response of Container-grown Nursery Plants to Chlorine Used to Disinfest Irrigation Water

The recycling of irrigation water may cause the dispersal of plant pathogens. Irrigation water disinfected with 2.4 mg·L−1 of free chlorine for 5 min was overhead-applied to 17 container-grown nursery plants for 11 weeks in a commercial nursery to evaluate the response of container-grown nursery plants to chlorine. No visual symptoms of injury or growth reduction were observed on the evergreen shrubs (Juniperus horizontalis, Thuja occidentalis, Buxus microphylla, Picea glauca, Rhododendron catawbiense, Taxus media, and Chamaecyparis pisifera), but there were visual injuries and/or growth reduction on some of the deciduous shrubs (Salix integra, Hydrangea paniculata, Prunus ×cistena, Weigela florida, Physocarpus opulifolius). Symptoms of anthracnose were reduced on Cornus alba plants treated with chlorinated water. The chlorine treatment did not affect leaf chlorophyll content. The chlorine treatment killed all fungi and oomycetes in the irrigation water (DNA multiscan). Although there were visible leaf injuries and growth reduction on some of the deciduous plants, chlorine injury did not render them unsalable. Results suggest that irrigation water treated with 2.4 mg·L−1 free chlorine for 5 min will effectively control the dispersal of common plant pathogens without reducing the market value of container-grown plants.

Efficacy of Metarhizium anisopliae as a Curative Application for Black Vine Weevil (Otiorhynchus sulcatus) Infesting Container-Grown Nursery Crops

Abstract The black vine weevil (BVW), Otiorhynchus sulcatus (F.) is a serious pest of nursery crops. The fungus, Metarhizium anisopliae (F52), is registered by the U.S. Environmental Protection Agency for BVW control. The objectives of this study were to determine the efficacy of a curative drench application of M. anisopliae for controlling BVW larval infestations in container-grown nursery plants and the effect of temperature on the rate of fungal growth and speed of kill. Trials evaluating the efficacy of M. anisopliae as a curative application were performed in the spring of 2004 and 2005 as well as the fall of 2006. Laboratory studies were performed to quantify the impact of temperature (10, 15, 20, 24 and 28C) on fungal growth and speed of kill. Metarhizium anisopliae applied in the greenhouse and outdoors in 2004 were 92 and 30% effective, respectively. Fungal applications to container-grown plant material maintained outdoors in the spring of 2005 were nearly 100% effective 28 days after application. Fall applications in 2006 provided statistically significant reductions in the number of live BVW larve per pot, but were not as effective as spring applications in 2005. The mean media temperature of containers maintained outdoors in the fall of 2006 dropped considerably (10–12C) over the course of the experiment and were likely the cause for the reduced efficacy. Laboratory experiments demonstrated that temperatures below 20C (68F) significantly slowed fungal growth and the speed at which M. anisopliae infected BVW larvae. In the field, drench applications of M. anisopliae were very effective at eliminating BVW larvae in container-grown nursery plants when media temperatures were adequate (> 15C (59F)). The use of M. anisopliae as a curative drench application has similar temperature-dependent limitations as the use of entomopathogenic nematodes for BVW control. Therefore, applications should occur as early in the fall as possible once egg laying has ended or in late spring just prior to pupation when media temperatures would be most conducive to fungal infection.

First Report of Southern Blight on Firewheel Tree, Bay Laurel, Bird of Paradise, Mediterranean Fan Palm, and Liverwort Caused by Sclerotium rolfsii in Italy.

During the summer of 2006, a widespread blight was observed on 6-month-old potted plants of firewheel tree (Stenocarpus sinuatus Endl.) and 3-month-old potted plants of bay laurel (Laurus nobilis L.) growing in a nursery in eastern Sicily, Italy. On both species, symptomatic plants initially had sunken, tan lesions at ground level where white mycelia and small (1 to 2 mm in diameter), brown, spherical sclerotia typical of Sclerotium rolfsii Sacc. were formed. As the disease progressed, the mycelia extended up the stem and entire plants collapsed. A sudden wilting affecting 4-month-old potted seedlings of bird of paradise (Strelitzia reginae Aiton) and 5-month-old potted seedlings of Mediterranean fan palm (Chamaerops humilis L.) was occasionally detected in other greenhouses of the same nursery. Liverwort (Marchantia polymorpha L.) was abundantly present on the surfaces of the containers where these plants were grown. Circular and crescent-shaped patches as much as 100 cm in diameter were observed on the massed liverwort plants. In these patches, the liverwort died and sclerotia typical of S. rolfsii were dispersed on white mycelial strands. Symptomatic tissues of the ornamental plants and liverwort were surface disinfested in 1% NaOCl for 1 min, rinsed in sterile water, and plated on potato dextrose agar. Tissues consistently yielded S. rolfsii (teleomorph Athelia rolfsii (Curzi) Tu & Kimbrough) and typical sclerotia with internally differentiated rind, cortex, and medulla were produced within 6 or 7 days (3). Pathogenicity tests were performed by placing 30 sclerotia obtained from 10-day-old cultures in the soil below the crown portion on each of 2-month-old healthy seedlings of Stenocarpus sinuatus, L. nobilis, Strelitzia reginae, and C. humilis (20 seedlings per host). In addition, liverwort growing in 10 pots (7 cm in diameter) was inoculated with 30 sclerotia per pot. For each species, the same number of plants or pots served as control. All ornamental plants and liverwort were maintained in a growth chamber at 25 ± 1°C and enclosed for 7 days in polyethylene bags and then moved to a greenhouse where temperatures ranged from 24 to 28°C. The inoculation trial was repeated once. Symptoms of southern blight developed after 5 to 20 days on all inoculated plants of Stenocarpus sinuatus and sporadically (two to five plants) after 20 days on L. nobilis, Strelitzia reginae, and C. humilis. After 5 days, liverwort in all inoculated pots was colonized and plants died within 12 days. Control plants of all species remained symptomless. S. rolfsii was reisolated from symptomatic plants. S. rolfsii was reported for the first time in Sicily in 2004 on ornamental plants (2). Strelitzia reginae was previously reported as a host of Corticium rolfsii (synonym S. rolfsii) in Portugal (1). To our knowledge, this is the first report of S. rolfsii on Stenocarpus sinuatus, L. nobilis, and C. humilis. In addition, this is the first report of the susceptibility of M. polimorpha to S. rolfsii. Liverwort could provide a food source for the fungus in container-grown nursery plants.

Dynamic Modeling of Tension-Controlled Irrigation of Container-Grown Nursery Plants

A mathematical model of a closed-loop feedback control system for controlling microirrigation of container-grown nursery plants was developed and tested. Moisture tension in the container medium was the control variable. The system's characteristic transfer function parameters included a time delay (infiltration time), on-off control (irrigation pump), pumping rate, mass of potting medium, moisture tension as a function of potting medium moisture, and a tensiometer response function. Calibration and validation of the model was done using experimental data collected for Red Sunset red maple (Acer rubrum 'Red Sunset') during late summer of 1997. A time-varying, vapor pressure deficit/evapotranspiration transfer function, ETVPD, was used to estimate the plant's rate of removal of water from the root medium (R2 = 0.684). The transfer function underestimated total irrigation water by 25% and overestimated irrigation frequency by 37.5% (11 vs. 8 cycles) during the 14-day experimental validation period. Major differences between experimental validation and simulated results were attributed to the accuracy of the ETVPD model and the use of zero infiltration time (tDT). Key factors identified as directly affecting stability and accuracy of tensiometer-controlled irrigation, in addition to the identified system's parameters, were size of the plant root system and placement of the tensiometer(s). Results showed that only 18% of the total soil medium mass was affecting the systems response function based on the experimental setup of one tensiometer in the potting medium.

Taxodium Growth Under Different Substrate Moisture Levels

Water is quickly becoming one of the world's most precious resources. Micro- and cyclical irrigation are two effective ways that reduce irrigation volume without reducing plant quality. Development of a control mechanism to deliver timely and appropriate irrigation volumes combined with the advantages of micro- and cyclical irrigation will allow maximum water conservation and plant quality. For container-grown nursery plants, the interaction of container geometry and media physical properties dictate the volume of water available for plant uptake. The maximum amount of water a container substrate can hold under gravity is container capacity (CC). We managed season-long irrigation volumes by maintaining CC at three levels; 100% CC; 80% CC; and 60% CC, and used a set irrigation as a commercial control. The results showed similar plant growth for the 100% and set irrigation control groups through the growing season. However, the scheduled regime applied 50% more water than the group maintained at 100% CC. Our system increased water use efficiency without decreasing plant quality.

Comparison of Chopped Newspaper with Microfoam for Winter Protection of Container-grown Nursery Stock

Chopped newspaper at 3.5 and 7.0 kg.m-2 enclosed in white polyethylene sheeting or enclosed in nylon netting at 3.5 kg.m-2 was compared with two layers of 0.64-cm microfoam as winter covering of four taxa of container-grown nursery plants. White polyethylene-enclosed newspaper moderated winter temperatures more than net-enclosed newspaper or two layers of microfoam under white polyethylene. All coverings provided protection against winter injury, as evidenced by container temperature, but net-enclosed newspaper at 3.5 kg.m-2 resulted in a minimal percentage of Daphne burkwoodii `Carol Mackie' plants with three or more shoots longer than 2 cm in the spring. Gaillardia grandiflora, covered by newspaper during winter, had less spring growth than plants covered by microfoam, but all coverings provided protection for Juniperus horizontalis `Prince of Wales' and Physostegia virginiana.

EFFECT OF PAPER MULCH ON WINTER TEMPERATURES OF CONTAINER-GROWN NURSERY PLANTS

Five species of container-grown nursery plants were overwintered under treatments of no cover, 2 layers of microfoam, 15 or 30 cm of chopped newspaper and 15 cm newspaper or 22 cm straw between two layers of white copolymer. Temperatures were measured in the air under covers and in the center of the growing medium. Chopped newspaper moderated winter temperatures equal to or better than other cover treatments. All covers prevented winter injury. Baled chopped newspaper used by dairy farmers for livestock bedding is available at a reasonable cost.

Root Dip Treatments for Controlling Blueberry Stem Blight Caused byBotryosphaeria dothideain Container-Grown Nursery Plants

Root Dip Treatments for Controlling Blueberry Stem Blight Caused by<i>Botryosphaeria dothidea</i>in Container-Grown Nursery Plants

Tolerance of Woody Nursery Stock to Classic (chlorimuron) and Harmony (thiameturon)

Abstract Classic and Harmony applied at rates ranging from 0.009 kg ai/ha (0.008 lb ai/A) to 0.067 kg/ha (0.06 lb/A) provided excellent preemergence and postemergence control of common groundsel (Senecio vulgaris L.) 5 weeks after application to container-grown nursery plants. Classic at 0.034 kg/ha (0.03 lb/A) and 0.067 kg/ha (0.06 lb/A) reduced yellow nutsedge (Cyperus esculentus L.) growth by 50 to 77% 5 weeks after preemergence or postemergence treatments. Harmony did not affect yellow nutsedge from either type of application. ‘Seagreen’ juniper (Juniperus chinensis L.), ‘Blue Pacific’ juniper (Juniperus conferta Parl.) and ‘Bennetts Compacta’ holly (Ilex crenata Thunb.) tolerated all rates of Classic and Harmony. ‘Girard's Rose’ (Rhododendron kaempferi Planch.) and ‘Coral Bells’ azale(Rhododendron obtusum (Lindl.) Planch.), and redtip photinia (Photinia × Fraseri Dress) were initially injured by these herbicides, but outgrew the foliar damage.

Production of container-grown nursery plants on capillary sand beds

This study investigated the effect of growth medium on the growth of nursery plants in a capillary irrigation system, the use and amount of slow-release fertilizer for the fertilization of container-grown nursery plants, and the need fora base dressing with a slow release fertilizer. Also investigated were the effect of different concentrations of alkyl aryl trimethyl ammonium chloride solution (Gloquat C) in preventing rooting through, and the use of a watering control device based on measuring radiation energy in field conditions. The experiments on growth medium revealed that all the growth media included in the experiment, i.e. sphagnum peat, peat/rock wool mixture (1 : 1),or peat/sand mixture (3 : 1), can be used for container-grown nursery plants if a base dressing is used with Nutricote(70), a slow-release fertilizer. The effect of slow-release fertilizer was better in peat mixtures, and this effect was especially clear when no base dressing was used. The use of slow-release fertilizer proved to be a good fertilization method in a capillary irrigation system. The fertilizing effect of Nutricote (70) given in the spring lasted until early June of the following year. Nutricote(70) was found to need a base fertilizer dressing. Abase dressing of 1.2 kg/m3 of a compound fertilizer (Turpeen Y-lannos; N 11 % P 10.5 %, K 18.3 %) with 1.5 kg/m3 of slow release fertilizer proved to be a suitable fertilization method for ornamental woody nursery plants in a capillary irrigation system. The tallest plants were obtained with a base dressing that was mixed with 3 kg/m3 of the slow-release fertilizer. Plants thus fertilized were, however, considered to be too large for transport and handling. The problem of a secondary root ball under the pot in sand beds was prevented by spreading 15 ml/m2 of Gloquat C on the sand surface. The capillary irrigation system and the automatic irrigation control worked well in experiments carried out under practical conditions. The potted nursery plants were kept evenly moist, and the plants grew to market size in one growing season.

Coverings for Overwintering Container Grown Plants in Northern Regions

Several methods were compared for moderating temperatures and protecting container-grown nursery plants from winter injury. Three layers of microfoam covered by 1 layer of 4 mil white copolymer (poly) and 30 cm (12 in) straw between 2 layers of white poly greatly moderated minimum temperatures of growing medium. The straw-between-white poly treatment prevented rapid rise of air temperatures under the cover in early spring. All covers resulted in minimal winter injury to most plant species, but growing medium temperatures in containers under 1 layer of microfoam or 1 layer white poly dropped below −10°C (14°F), the temperature shown to be injurious to root systems of some plants.