Breeding programs around the world continually collect data on large numbers of individuals. To be able to combine data collected across regions, years, and experiments, research communities develop standard operating procedures for data collection and measurement. One such method is a crop ontology, or a standardized vocabulary for collecting data on commonly measured traits. The ontology is also computer readable to facilitate the use of data management systems such as databases. Blueberry breeders and researchers across the United States have come together to develop the first standardized crop ontology in blueberry (Vaccinium spp.). We provide an overview and report on the construction of the first blueberry crop ontology and the 178 traits and methods included within. Researchers of Vaccinium species—such as other blueberry species, cranberry, lingonberry, and bilberry—can use the described crop ontology to collect phenotypic data of greater quality and consistency, interoperability, and computer readability. Crop ontologies, as a shared data language, benefit the entire worldwide research community by enabling collaborative meta-analyses that can be used with genomic data for quantitative trait loci, genome-wide association studies, and genomic selection analysis.
Ginger (Zingiber officinale Rosc.) is a valuable sciophyte crop used as a spice or fresh herb in culinary dishes and for treating medical issues such as osteoarthritis, neurological diseases, vomiting, and asthma. The demand for ginger in the United States is remarkably high; it is produced commercially and exclusively in Hawaii but can only meet ∼20% of US demand. Light for ginger growth may be more important than is often assumed, but the roles of light in ginger growth and rhizome yield are not fully understood. We hypothesized that artificial shade would produce the highest yielding ginger compared with no shade. This study evaluated the impact of different shading suited for ginger growth and rhizome yield of different cultivars grown in a high tunnel. There were three levels (0%, 22%, and 40%) of shade using RCBD design. We analyzed the overall yield (weight) of ginger and the specific yield (weight) of different rhizome parts (biological root, edible root, and seed ginger) per plant in addition to plant growth data. Data were analyzed for 2018 and 2019, and shade conditions influenced ginger growth and yield. There was no significant difference between shade conditions or cultivars, but general trends found that data differed between the two growing seasons. In 2018, Chinese White and Hawaii Yellow produced a better (higher) yield under 0% and 40% shade. However, in 2019, Chinese White and Hawaii Yellow produced the highest total yield under 22% shade, but Bubba Blue produced the highest overall yield at 0% shade.
Two common challenges reported by cannabis growers are low yields and small profit margins. Although recent research of cannabis yield has focused on lighting and nutrition, little research has examined how changes in other cultivation practices may be beneficial. The objective of this study was to evaluate the following two techniques to potentially improve yield: fertilizer restriction (FR) to reduce plant size and, thus, increase plant density and shoot number manipulation (SNM) to reduce shoot length and improve biomass partitioning. The FR technique involves leaching the substrate and providing only tap water for 0, 1, or 2 weeks at the start of flower initiation, whereas SNM involves pinching shoot tips 2, 3, or 4 times to produce 4, 8, or 16 shoots/plant, respectively. This study used a full factorial treatment design for a total of nine treatments (three FR × three SNM). Plants were flowered under 12-hour photoperiods for 8 weeks and then destructively harvested for data collection. The results demonstrated that both techniques improve plant productivity in different ways. The FR technique reduced all mass measurements (g/plant) and decreased plant area (m2/plant); therefore, the yield metrics (kg·m−2) increased with the increasing FR treatments. The SNM technique did not affect plant area, but more pinching events resulted in a decrease in reproductive shoot length (cm/shoot) and an increase in inflorescence to trim the dry mass ratio (inflorescence:trim). Shorter shoot lengths are desirable for eliminating trellis support netting, which helps growers reduce material costs and improve labor efficiency during harvest. Increasing the inflorescence:trim may also reduce labor costs related to trimming, which comprise the largest cost of production by many growers. Although both techniques offer advantages, there are trade-offs that must be considered in the context of overall profitability.
Bulk density (Db) and subsequent physical properties are determined by the substrate and packing method. Packing method is the way one fills and compresses a substrate within a given volume. Bulk density produced in the laboratory may not align with “expected” published ranges due to variations in packing. Additionally, it is unknown if ranges identified as “typical” using a small volume sample ring reflect Db occurring in larger production size containers packed using commercial potting practices. Therefore, our objectives were to 1) emulate nursery practices and document the Db associated with a potted 2.8-L (#1) container, 2) develop and test the new “shim and compression” method to determine if it consistently packs sample rings to a Db commensurate with that of a 2.8-L nursery container, and 3) demonstrate how static physical properties are affected by the new “shim and compression” sample ring packing method compared with the traditional bench top tap method. When emulating nursery potting practices with 100% pine bark, coir, and peat, and blends of each, Db ranged from 0.08 g⋅cm−3 (coconut coir) to 0.17 g⋅cm−3 (pine bark). We used an espresso tamp and shims to pack the aforementioned substrates in sample rings. The Db achieved using a range in number of presses and discs was largely dependent on the substrate, but the desired Db was consistently achieved for each substrate. There was no effect of disc number on Db (P = 1.000) for any substrate. There was no effect of tamp number (P ≥ 0.0602) for all substrates except peat-amended, for which five tamps yielded a greater Db than one tamp (P = 0.0324). In an experiment in which a different technician who was accustomed to the conventional benchtop tap packing method performed both methods, method influenced Db (P < 0.0001), and the conventional method more closely attained the target Db. To our knowledge, this is the only report of Db observed in commercial container production facilities (i.e., “native”).
The limited availability of peat-based substrates, a nonrenewable resource, and the negative environmental impacts associated with their extraction require the conservation of this resource. We assessed the use of cattle dung compost as a stand-alone nursery substrate, replacing peat substrate for the production of lettuce (Lactuca sativa L.) seedlings. A completely randomized design was employed, using cattle dung compost (C) and commercial peat (P, control treatment) in various combinations (100% P; 25% C/75% P; 50% C/50% P; 75% C/25% P; 100% C) to assess their effects on different growth parameters of lettuce. Twenty-eight parameters (e.g., seed germination, seedling survival, diameter, height, biomass growth) were assessed, corresponding to the time when the seedlings are transplanted. All treatments achieved 100% seed germination and seedling survival; indicating the successful establishment of lettuce seedlings across all tested substrates. However, seedling growth was found to be significantly influenced by substrate type. Seedling diameter was significantly increased by 10.8% in the 50% C/50% P substrate, while seedling height was significantly increased by 7.7, 6.8, and nearly 10%, respectively, within the 25% C/75% P, 50% C/50% P and 100% C substrates, relative to the control. Other substrate treatments were not significant. Similar or significantly higher values than the control were also observed for biomass growth under the tested substrates, indicating the beneficial effect of cattle dung on the initial growth of plants during the nursery phase. Cattle dung compost, used as a growing substrate, demonstrated similar or superior results to commercial peat, suggesting its potential as a viable alternative potting medium for sustainable horticulture.
The underlying therapeutic mechanisms of care farming activities have not been addressed using psychophysiological data. We aimed to understand frontal cortex activation in adults during care farming activities and to explore the psychophysiological effects. Using a randomized crossover study method, 20 adults (average age, 31.3 ± 9.8 years) participated in 10 care farming activities, (four gardening activities, three animal-mediated activities, and three off-farming activities) for 3 minutes each at an actual care farm. Electroencephalography (EEG) was performed during the activity, and emotional states were assessed using subjective emotional questionnaires after each activity. The EEG results revealed that alpha activity increased during gardening activities, such as organizing garden plots and planting plants. Spectral edge frequency 50, which predicts the degree of arousal, increased during interaction with dogs. The results of the subjective emotional questionnaire revealed that participants experienced positive emotions, such as vigor, comfort, naturalness, and relaxation, when participating in care farming activities compared with those while resting. Therefore, this study suggests that care farming activities can induce changes in the frontal cortex activation and positive emotional states in participants. This study elucidates the use of such activities to address mental health-related issues.
Nitrogen (N) is one of the most important fertilizers in agriculture because it promotes the growth of plants and the uptake of other plant nutrients. This nutrient plays a significant role in determining the yield and nutrient composition of sweet potato root tubers. Therefore, this study aimed to determine the optimum application rate of N in sweet potatoes to maximize yields and increase growth efficiency. Four levels of N (50, 100, 150, and 200 kg/ha) were applied as treatments. A randomized complete block design was used, and each treatment was replicated five times. Vine length, leaf length, stem thickness, and chlorophyll content were measured weekly, and the storage root yield was determined at the end of the experiment. The results showed a significant effect of the N treatments on plant growth, chlorophyll content, vine length, leaf area index and storage root yield. The chlorophyll content and vine length increased with an increase in the N rate. However, an inverse relationship was observed between storage root yield and N rates; the highest yield was recorded for the 50 kg/ha N treatment and the lowest yield was recorded for the 200 kg/ha N applied. Therefore, a rate of 50 to 100 kg/ha N is recommended for the production of orange-fleshed sweet potatoes.
Microgreens are young plants used as ingredients and flavoring in various dishes. Their production time is short, and their production methods can be altered to enhance the nutritional content. To date, consumers’ preferences for microgreens that display different esthetic and nonesthetic traits have not been addressed. Additionally, consumers’ perceived risk of production methods used to enhance nutrition has not been investigated. An online survey and choice experiment involving a sample of 821 consumers in Tennessee were performed to investigate these topics. A mixed logit model was used to analyze the data. Both esthetic and nonesthetic traits influenced the consumers’ preferences. Green microgreens were preferred and valued more than light or dark purple microgreens. When fertilizer was used during production to enhance nutrients, consumers perceived the microgreens as riskier to the environment and for personal consumption relative to microgreens with light-induced nutrient enhancement. Using lighting during production to enhance nutrients generated a $0.47 to $0.79 premium relative to no nutrient enhancement. In general, if participants’ perceived risk aligned with the nutrient enhancement attribute (i.e., light, fertilizer), then their willingness to pay for the microgreens decreased. This was amplified for the fertilizer nutrient enhancement attribute more than it was for the light enhancement attribute. In-state production and microgreen height also impacted consumer preferences for microgreens.