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‘Coy’ alder-leaf mountain mahogany (Cercocarpus montanus) is a new cultivar developed from a species native to the western United States with potential for use in xeriscaping, rock gardens, and water-efficient landscaping. However, efficient propagation methods are not well developed for it. In this study, cutting propagation of ‘Coy’ alder-leaf mountain mahogany was investigated over 3 years to evaluate the effects of wounding method, rooting hormone, type of cuttings collected, and time for cutting collection on rooting. In May, Jul, and Sep 2020, 2021, and 2022, nondormant hardwood subterminal cuttings and/or semihardwood terminal cuttings were collected for wounding studies. Before the treatment with 3000 mg·L⁻¹ indole-3-butyric acid (IBA) in powder, cuttings were wounded either by scraping one side (scrape) or by perpendicular cuts around the base (cut), and cuttings without additional wounding were used as the control. Similarly, subterminal and terminal cuttings of ‘Coy’ alder-leaf mountain mahogany were collected during the same time and were used for hormone treatments. Cuttings were treated with 1000 or 3000 mg·L⁻¹ IBA in powder or 1000/500 or 3000/1500 mg·L⁻¹ IBA/NAA (1-naphthaleneacetic acid) in solution. Wounding by cut or scrape increased the rooting percentage. In addition, most cuttings wounded by the scrape method had better rooting than those wounded with cuts. On the basis of hierarchical cluster analyses, cuttings treated with 3000 mg·L⁻¹ IBA in powder had greater rooting than those treated with other hormones. Therefore, our research showed that successful rooting of subterminal or terminal stem cuttings of ‘Coy’ alder-leaf mountain mahogany can be achieved through wounding using scrape method and by treatment with 3000 mg·L⁻¹ IBA in powder.

The University of Connecticut Extension Sustainable Landscapes program seeks to develop an invasive plant training program to equip stakeholder groups of varied experiential backgrounds with the information needed to evaluate, manage, and mitigate populations of invasive species in Connecticut. A mixed methods needs assessment was conducted to explore diverse viewpoints about invasive plant education. Data were collected from 233 survey respondents and three focus group interviews. Landscape professional/contractors and municipal employees totaled 41.1% of respondents when combined, and home gardeners totaled 27.9%. The greatest programmatic need identified by survey respondents was invasive plant management options and strategies, with Japanese knotweed considered the most problematic invasive plant from a list of 16 species. Focus group participants expressed enthusiasm about targeted educational programming, such as efforts focused on land management principles, species identification, state regulatory agencies, and pesticide application. Many shared the need for enhanced public education efforts and resource availability. A hybrid approach, including virtual and in-person components, was recommended as the ideal delivery modality for an invasive plant training program.

Selenium is an essential mineral for both humans and animals. Around 0.5–1 billion individuals globally suffer from selenium deficiency, which can result in a range of illnesses. Hence, the cultivation of selenium-enriched agricultural items can serve as a potent strategy to mitigate selenium deficiency. This study aimed to examine the effect of selenium on the quality, and phytochemical and mineral content of red currant (Red Lake) and jostaberry. The study was conducted in 2022 and 2023. Different doses of selenium (0, 4, and 8 mg⋅kg⁻¹) were sprayed on the fruits three times with 10-days intervals starting from the first formation of the fruits after flowering. Upon completion of the study, various factors were assessed including cluster and berry properties, water-soluble dry matter content, pH levels, titratable acid content, ascorbic acid levels, antioxidant activity, and total phenolics content. The mineral composition of the fruit peel, pulp, and seed was also measured. In jostaberry, the highest values of cluster weight, cluster height, and 100-berry weight were obtained with 8 mg⋅kg⁻¹ selenium application. As the selenium dosage increased, the levels of ascorbic acid, antioxidant activity, and total phenolic content increased, with the highest values determined to be 0.063 mg⋅mL⁻¹, 63.23% DPPH, and 3752.22 mg⋅g⁻¹, respectively, at 8 mg⋅kg⁻¹. In the Red Lake variety, it has been determined that the 4 mg⋅kg⁻¹ dose is effective in terms of cluster weight, cluster width, and cluster height attributes. The highest values for ascorbic acid, antioxidant activity, and total phenolic content were determined to be 0.029 mg⋅mL⁻¹, 53.42% DPPH, and 3117.17 mg⋅g⁻¹, respectively, at the 4 mg⋅kg⁻¹ dose. The selenium content was found to be highest in the peel and pulp of jostaberry at 8 mg⋅kg⁻¹, and in Red Lake, it was obtained at the 4 mg⋅kg⁻¹ application. As a result, an 8 mg⋅kg⁻¹ dose of selenium could be recommended for jostaberry, and a 4 mg⋅kg⁻¹ dose could be recommended for Red Lake.

Drought and salinity affect turfgrass growth and development adversely. Plant growth-promoting microorganisms (PGPMs) have been shown to have the capability of improving resistance to biotic stressors in plants. The objective of this research was to determine the efficacy of six commercial PGPMs on enhancing the drought and salinity resistance of kentucky bluegrass (Poa pratensis). The six PGPMs evaluated were Beauveria bassiana (strain GHA), Bacillus subtilis (strain GB03), Azadirachtin, Bacillus firmus (strain 1-582), Trichoderma harzianum Rifai (strain T-22) combined with Trichoderma virens (strain G-41), and Bacillus subtilis (strain QST713). Three cultivars—Kenblue, Moonlight, and Waterworks—were seeded in the greenhouse. Two-week seedlings were exposed to saline (sodium chloride at 6 dS⋅m^–1 three times per week) or drought (tap water once per week) conditions, and no stress (irrigated with tap water three times per week) for 4 weeks. Results show that drought and salinity inhibited turf growth, with the greatest reduction in root dry weight (50.3% in drought conditions and 31.4% in saline conditions). ‘Kenblue’ performed better than ‘Waterworks’ and ‘Moonlight’ in all growth indices except for root length. Beauveria bassiana and B. subtilis had a similar or better result in enhancing turfgrass growth and development compared with the untreated turf under stress. Our results suggest that certain PGPMs have the potential to improve abiotic stress resistance in turfgrass.

In this study, we document the primary structural changes that occur during the seed development of Paphiopedilum spicerianum (Rchb.f.) Pfitzer, an endangered species with high horticultural value. Within a defined timeline, our results offer insights into the connection between these structural changes in seeds and their germination percentage. The optimum germination was recorded for immature seeds collected at 180 to 210 days after pollination (DAP), during which the embryos are in the late globular stage and the suspensor begins to degenerate. As seeds continued to mature by 240 DAP, there was a gradual decline in germination. Histochemical staining of mature seeds reveals that only the inner seedcoat and the surface of the embryo exhibit positive reactions to the Nile red stain, suggesting a relatively weak coat-imposed dormancy. This weaker dormancy may contribute to the higher germination observed in mature seeds of P. spicerianum compared with other challenging-to-germinate species. Of the cytokinins examined, 6-(γ,γ-dimethylallylamino)purine (2iP), kinetin (KN), and 6-benzylaminopurine (BA) exhibited a stimulating effect on germination, concurrently enhancing the formation of amorphous protocorms.

Thirty sweetpotato (Ipomoea batatas var. batatas) genotypes were evaluated for yield, resistances to weevil or nematode pests, and consumer acceptance across three field trials planted at Pepe‘ekeo, Hawai‘i Island between 2017 to 2020. At harvest, storage roots were graded according to market standards, followed by scoring for damage by sweetpotato weevil (Cylas formicarius elegantulus), rough sweetpotato weevil (Blosyrus asellus), or nematodes; namely root-knot nematode (Meloidogyne spp.) or reniform nematode (Rotylenchus reniformis) in each market class. There were significant differences in marketable yields among accessions when data were analyzed statistically across all three field trials, as well as individually. ‘Regal’ (PI 566650) and ‘Sumor’ (PI 566657) were among the top three highest-yielding genotypes for Trials 1 and 2 (when no insecticides were applied to control weevils), and among the top six highest-yielding genotypes for the joint analysis across three trials. Significant differences among genotypes for combined sweetpotato weevil damage (incidence of sweetpotato weevil alone or incidence of both weevils together) were found in the joint analysis across three trials. ‘Regal’ was among the lowest seven genotypes for combined sweetpotato weevil damage, supporting earlier reports of its moderate resistance to this pest. In addition, two genotypes produced by the World Vegetable Center (Shanhua, Taiwan) (WT-320 and WT-108), were among the lowest genotypes for combined sweetpotato weevil damage, in agreement with earlier reports of their substantial resistance to this pest. Providing access to diverse germplasm will help farmers react to increasing pest pressure, while still allowing for high marketable yields. In addition, breeding and selection for pest resistance could be an important addition to integrated pest management of sweetpotato in Hawai‘i.

Health and quality of the root system are imperative to ensure the successful establishment of a citrus tree after transplant from the nursery into the field. Containerized citrus production in enclosed nurseries restricts root growth and can result in root circling and intertwining. This may hinder root expansion and result in root girdling after transplant, negatively affecting tree establishment and growth. The root structure of a transplanted citrus tree can also be affected by the container type used in the nursery. Containers with root-pruning properties like chemical pruning or air pruning reduce root circling and may produce superior root systems compared with regular, nonpruning containers. The aim of this study was to evaluate the effects of different nursery containers on root physiological and morphological traits and plant performance over 15 months of growth in the nursery. Three container types, chemical pruning containers, air-pruning containers, and standard nursery containers, were compared. The chemical pruning containers were standard citrus nursery containers with a mixture of copy hydroxide [Cu(OH)₂] and copper carbonate (CuCO₃) [10% copper (Cu)] applied to the inner wall. Pruning occurs upon contact of the roots with the Cu on the wall of the containers. The air-pruning containers were custom-sized Air-Pots in which pruning occurs on holes in the wall of the containers upon contact of the roots with the air. Two rootstocks, US-812 and US-942 (Citrus reticulata × Poncirus trifoliata), were included for comparison in the nongrafted stage and 12 months after grafting with ‘Valencia’ orange (Citrus sinensis). Chemical root pruning positively influenced tree height, shoot mass, leaf area, rootstock trunk diameter, and the nonfibrous root biomass. No differences among container types were observed for the fibrous root biomass, but chemical pruning produced more roots that were finer with a higher specific root length and a higher respiration rate. In contrast, air pruning produced more roots that were thicker compared with the other containers. Most of the leaf nutrients were lower in trees grown in the chemical pruning containers compared with the standard containers, except for Cu and zinc (Zn), which were highest in the former. Trees growing in air-pruning containers were not significantly different in growth from trees growing in standard containers.

Goosegrass, Eleusine indica (L.) Gaertn., is a serious weed in bermudagrass, Cynodon spp. Rich., golf and sports turf. Reduction of canopy gaps such as divots might discourage goosegrass establishment because turf canopy reduces sunlight that could stimulate goosegrass seed germination. The objective was to compare goosegrass seedling emergence and growth under different conditions of bermudagrass canopy, including bare soil and divots of different ages, and the effect of fertilization rates. The first experiment compared surface treatments. Goosegrass seeds were planted monthly for 12 months in bare soil and divoted pots in a glasshouse. Initial goosegrass seedling emergence was large in the first month after planting, 23% in divots and 20% in bare soil, compared with only 9% emergence from canopy. Reduced emergence occurred from 2 to 8 months in canopy, divots, and bare soil. Cumulative goosegrass emergence was 44% in divots, 40% in bare soil, and 31% in canopy. In a second experiment, goosegrass seeds were planted in divots 0, 2, 4, 6, 8, and 10 weeks old. Divots were visibly closed within 4 to 6 weeks. By 9 weeks after seed planting, goosegrass seedling emergence was reduced 72% after planting in 10-week-old divots compared with fresh, 0-week divots. Goosegrass continued to emerge through all 63 weeks observed after seed planting. High fertilization rate, 123 g N/m²/year, from 10 to 63 weeks reduced cumulative late seedling emergence 34%, compared with half-rate fertilization, probably due to denser canopy under high fertilization. In a third experiment, goosegrass seedlings planted in closed bermudagrass canopy grew 90% less, in root and shoot fresh and dry mass, compared with seedlings planted in divots. Across all experiments, goosegrass emergence and growth were reduced by increased canopy.

Blue honeysuckle (Lonicera caerulea) is a circumpolar species complex with representatives in Europe, Asia, and North America. Although honeysuckles (Lonicera spp.) from Eurasia have a history of invasiveness in North America, farmers and homeowners are interested in growing nonnative blue honeysuckle hybrids because of their edible blue fruits. To assess whether these cultivars and closely related native blue honeysuckles (Lonicera caerulea subsp. villosa) might have similar growth and fecundity, we planted five nonnative cultivars of blue honeysuckle and five native genotypes in a common garden in Orono, ME, USA, along with invasive red-fruited honeysuckles [Tatarian honeysuckle (Lonicera tatarica) and European fly honeysuckle (Lonicera xylosteum)] for comparison. Rooted cuttings were planted into a field plot in Jun 2016 and fully maintained during the first season; thereafter, maintenance consisted of weeding once annually. Seventy-three percent of native blue honeysuckle plants survived to the end of the study, whereas survival and growth of nonnative cultivars were more robust. In 2021, nonnative cultivars had an average height of 81 cm and width of 86 cm, which were 2.8 times the height and 2.9 times the width of surviving native plants. The estimated canopy volumes of nonnative blue honeysuckles were an average of 20 times those of their native counterparts. The bloom periods of native and nonnative blue honeysuckles overlapped considerably. However, only seven of the 22 living native plants produced fruits in 2021, with an average of three fruits per plant among them. In contrast, nearly all plants of the nonnative cultivars produced fruits, with an average of 616 fruits per plant. In comparison, the red-fruited invasives had an average of 9739 fruits per plant. Native blue honeysuckles produced very few seeds, whereas nonnative cultivars had an average of 13,918 seeds per plant, which was approximately one-fourth the number produced by invasive red-fruited honeysuckles. We concluded that native and nonnative genotypes of blue honeysuckle differ strikingly in survival, growth, and production of fruits and seeds. However, invasive red-fruited honeysuckles grew faster with higher fecundity than nonnative blue honeysuckles in our full-sun landscape. Because bloom times overlapped substantially between native and nonnative blue honeysuckles, the potential for gene flow to occur from planted cultivars into native populations merits consideration. Several possible explanations of differences in performance among blue honeysuckles include hybrid vigor of cultivars or shallow rooting or poor adaptability of native genotypes to the environment of the common-garden trial. Our results, which demonstrated that nonnative blue honeysuckles are likely to be distinct from their native relatives in terms of competitiveness and fecundity, suggest that caution is warranted during the introduction and cultivation of agricultural genotypes.

The nursery industry produces and sells plants for landscape and environmental purposes and represents a major sector within the US agricultural industry. In recent years, the nursery industry has undergone rapid growth as a result of various factors, including increased demand from housing development and pandemic-fueled interest in home horticulture. As with any industry, the nursery industry must adapt to changes in societal trends to sustain growth. In the wake of unprecedented societal and supply chain issues stemming from the global coronavirus disease 2019 pandemic, the American Society for Horticultural Science Nursery Crops Professional Interest Group gathered experts in various disciplines to provide their opinions and insights into the future of the nursery industry, focusing specifically on the changes and challenges the nursery industry will face in the coming decade. Nursery crop specialists spanning the United States identified three primary areas that will steer the future momentum of the nursery industry: consumer trends, natural resources, and labor. Six experts were selected to represent these areas in a workshop held Jul 2022 at the American Society for Horticultural Science Annual Conference in Chicago, IL, USA. This article was developed to disseminate to the greater scientific community the discussions held and insight shared during that workshop.