The efficacies of various acaricides in order to control a parasitic mite, the Varroa mite, Varroa destructor, of honey bees, were measured in two different settings, namely, in laboratory caged honey bees and in queen-right honey bee colonies. The Varroa infestation levels before, during, and after the acaricide treatments were determined in two ways, namely: (1) using the sugar shake protocol to count mites on bees and (2) directly counting the dead mites on the hive bottom inserts. The acaricides that were evaluated were coumaphos, tau-fluvalinate, amitraz, thymol, and natural plant compounds (hop acids), which were the active ingredients. The acaricide efficacies in the colonies were evaluated in conjunction with the final coumaphos applications. All of the tested acaricides significantly increased the overall Varroa mortality in the laboratory experiment. Their highest efficiencies were recorded at 6 h post-treatment, except for coumaphos and thymol, which exhibited longer and more consistent activity. In the honey bee colonies, a higher Varroa mortality was recorded in all of the treatments, compared with the natural Varroa mortality during the pretreatment period. The acaricide toxicity to the Varroa mites was consistent in both the caged adult honey bees and workers in the queen-right colonies, although, two of these acaricides, coumaphos at the highest doses and hop acids, were comparatively more toxic to the worker bees.

Salvia miltiorrhiza B., an herb used in traditional Chinese medicine, has been widely used to prevent and treat cardiovascular and other diseases. Currently, the majority of medicinal plants used in the US are imported from foreign countries, which involves transportation, quality control, and other issues. The objective of this study was to investigate the effect of nitrogen fertilization on growth and content of tanshinone I, tanshinone IIA, cryptotanshinone, and salvianolic acid B for Salvia miltiorrhiza B. in Mississippi. Plants were fertilized with one of five nitrogen (N) rates (0, 2, 4, 6, or 8 g N/plant from NH₄NO₃). Plants were harvested in November 2020 and 2021. Plants treated with 8 g N had higher plant growth index, leaf SPAD value, shoot and root number, shoot and root weight, maximum root length and diameter, shoot: root ratio, N concentration in root, and content of bioactive components compared to plants treated with 0, 2, 4 g N. Plants receiving 6 g N had similar shoot number, maximum root length, maximum root diameter, root weight and content of bioactive components compared to plants receiving 8 g N. However, plants receiving 6 g N had higher photosynthetic activity compared to plants receiving the higher N rate. Higher N rates increased plant growth and content of tested bioactive compounds.

Danshen (Salvia miltiorrhiza) is a perennial medicinal plant belonging to the Lamiaceae family. It is adapted to a wide range of soil pH with the potential to serve as an alternative crop in the United States. To enhance its cultivation and economic viability, it is crucial to develop production practices that maximize bioactive compound yields for danshen. The objective of this study was to investigate the effects of different harvest times on plant growth and subsequent yields of bioactive components of danshen. Three harvest times were selected (60, 120, or 180 days after transplanting [DAT]). In general, plants harvested at 180 DAT had higher plant growth index (PGI), shoot number, shoot weight, root number, maximum root length, maximum root diameter, and root weight compared to plants harvested at 60 or 120 DAT. However, plants harvested at 60 or 120 DAT had higher SPAD (Soil Plant Analysis Development) values. Plants harvested at 120 or 180 DAT had a higher content of tanshinone I, tanshinone IIA, cryptotanshinone, and salvianolic acid B compared to those harvested at 60 DAT. This study provides insights for optimizing the time of harvest of danshen to maximize plant growth and bioactive compound production.

Use of foliar auxin applications are increasing in the nursery and greenhouse industry. However, previous research has shown that insufficient auxin is absorbed or translocated to the site of action when foliar auxin applications are used. It is theorized that adding surfactants to foliar applications of auxin may help with the absorption and translocation of auxin to the site of action. Research was conducted to determine whether adding surfactants to one-time foliar applications of indole-3-butyric acid (IBA) would be as effective as the current industry standard, the basal quick-dip. Terminal, semi-hardwood cuttings of Red Cascade™ miniature climbing rose (Rosa ‘MOORcap’), common camellia (Camellia japonica) and ‘Southern Charm’ magnolia (Magnolia grandiflora ‘Southern Charm’) were sprayed to the drip point using Hortus IBA Water Soluble Salts™ at concentrations of 0 ppm, 50 ppm, 75 ppm, or 100 ppm for rose cuttings or 0 ppm, 500 ppm, 1000 ppm, or 1500 ppm IBA for camellia or magnolia. To serve as an industry control, the basal end of cuttings was immersed for 3-s in a solution of either 250 ppm, 4000 ppm or 2500 ppm for rose, camellia, or magnolia, respectively. A foliar application of 1500 ppm after sticking was as effective as the basal quick-dip for cuttings of ‘Southern Charm’, while other spray treatments were less effective. A basal quick-dip was more effective than a foliar spray for rooting cuttings of camellia. Auxin rate had no impact on rooting of Red Cascade^™ miniature rose. The goal of commercial plant propagation is to produce high-quality rooted cuttings as quickly as possible. Plant propagation places a large demand on labor within the nursery industry, with one recent report being that labor accounts for >50% of a nursery’s budget. Our results from this trial affirm the results reported by similar trials into foliar applications of auxin suggests that the benefits of foliar applications are species dependent Further work is warranted on examining other auxin and surfactant formulations.

Plant propagation is a labor-intensive process in the nursery and greenhouse industry, with labor accounting for 41.4% of expenditures in 2019—$4.8 billion of the $11.6 billion total. Labor availability remains a critical issue, and current methods of applying root-promoting compounds to cuttings often yield inconsistent rooting responses. This research investigated honey as a rooting adjuvant and its effects on rooting in Red Cascade™ miniature rose (Rosa ‘MOORcap’), common camellia (Camellia japonica), and southern magnolia (Magnolia grandiflora ‘Little Gem’). For Red Cascade™ rose, adding honey to water-soluble indole-3-butyric acid (IBA) solutions did not improve root counts compared to IBA alone. However, 1000 µL∙L⁻¹ IBA produced more roots than 250 µL∙L⁻¹ IBA. Camellia and magnolia cuttings were treated with multiflora, Manuka, or commercial honey, alongside IBA rates of 0 to 4500 µL∙L⁻¹. In camellia, honey type or auxin rate did not significantly affect rooting, but local and multiflora honey combined with higher IBA rates increased root counts. For magnolia, multiflora honey improved both root number and quality, outperforming other treatments. While honey showed limited benefits for camellia and rose, multiflora honey demonstrated potential economic advantages for magnolia propagation, enhancing root quality and quantity for producers.

Danshen (Salvia miltiorrhiza) is an herbaceous plant widely used in the pharmaceutical industry. However, the majority of medicinal plants utilized in the US are imported, posing challenges such as fluctuations in bioactive compound concentrations and insufficient supply to meet demand. Determining the optimal plant density is a key management decision for danshen production. This study aimed to investigate the effects of different plant densities on the growth and bioactive compound content of danshen cultivated in Mississippi. A field experiment was conducted to investigate the effects of different plant densities on individual plant growth, photosynthesis, and the content of bioactive components in danshen in 2020 and 2021. Six plant densities were designed: 30 × 20 cm (between row spacing × within row spacing), 30 × 30 cm, 30 × 40 cm, 45 × 20 cm, 45 × 30 cm, or 45 × 40 cm. A plant density of 45 × 40 cm resulted in danshen plants exhibiting the highest Plant Growth Index (PGI), SPAD, root number, shoot number, shoot fresh and dry weight, maximum root diameter, maximum root length, net photosynthesis, intracellular CO₂ concentration, tanshinone I, and cryptotanshinone, regardless of year. Plants spaced at 45 × 30 cm had similar root fresh weight, root dry weight, and tanshinone IIA and salvianolic acid B levels compared with plants grown at the 45 × 40 cm spacing, and both were significantly higher than other densities.