Biostimulant products have various reported benefits for plant production in the field or using hydroponic systems in protected structures. However, limited information is available describing their potential use for indoor farming applications. Considering that lettuce (Lactuca sativa) is one of the most popular crops produced in commercial indoor farms, the objective of this study was to compare growth and quality of lettuce grown indoors using nine biostimulant products derived from humic substances, amino acids, hydrolyzed proteins, or seaweed extracts. ‘Monte Carlo’, ‘Fairly’, and ‘Lalique’ lettuce were grown hydroponically for 30 to 33 days under a daily light integral, day/night temperature, relative humidity, and carbon dioxide concentration of ≈13 mol·m‒2·day‒1, 22/21 °C, 70%, and 800 µmol·mol‒1, respectively. There were no positive effects from using any of the biostimulant products evaluated in our study as growth (leaf area, leaf number, shoot diameter, and shoot and root dry weight), yield (shoot fresh weight), and quality (bolting, tipburn index, leaf color, and SPAD index) of treated plants were generally similar to those from the untreated control. Applications from one seaweed extract caused slight negative growth effects, possibly due to phytotoxicity. Cultivar differences showed that Fairly plants had the highest susceptibility to tipburn and bolting, and none of the biostimulant products countered these symptoms. Overall, the products evaluated provided marginal advantages for indoor hydroponic lettuce production.
Golf course superintendents are often under pressure to maintain high-quality turf. Such demand entails use of inputs, which can include biostimulants that are often marketed as a way of combating plant stress and improving turf quality. However, the extent of their use by superintendents and their level of efficacy are not well understood. This survey study was designed to better describe biostimulant use by the golf industry and to gain insights on the research needs of superintendents to address them effectively. A survey instrument was developed using online software and included a total of 13 questions relating to general familiarity with biostimulants and specific familiarity with five biological products. The instrument was disseminated electronically via the online survey tool to attendees (N = 80) during the annual conference of the Georgia Golf Environmental Summit in 2022. The respondents were from 62 golf courses, geographically representing the entire state of Georgia. The response rate was 62.5%. The majority of the respondents (86%) were familiar with biostimulants. The main reason for using biostimulants was predominantly agronomic, indicating a focus on turf performance and aesthetics. Of the respondents who used biostimulants, the overwhelming majority (93%) use humic acids and plant growth hormone-containing biostimulants. Respondents also indicated that research in microbial products would be the most relevant to the industry. This may be explained by the challenges in using such products (shelf life and microbial survival in soil). In conclusion, the survey indicated that Georgia golf course superintendents have high a level of familiarity with biostimulants. The survey yielded useful results to help formulate future research objectives to better serve the Georgia golf course industry.
Clematis (Clematis ×hybrida) has not traditionally fit into the standard production system for vegetatively propagated herbaceous perennials because of the lack of commercially available unrooted cuttings and relatively poor rooting success. We investigated strategies to improve stock plant production and propagation of clematis. The first experiment compared the propagation performance of four cultivars (H.F. Young, Reiman, Little Duckling, and Pinky). The second experiment examined cutting productivity and propagation performance of clematis cultivars when stock plants were grown at 21 or 27 °C and propagated with or without the application of rooting hormone. Stock plants grown at 27 °C resulted in greater cutting numbers and greater dry weights in the rooted cuttings after propagation. The third experiment demonstrated the effects of the origin of the cuttings of the stock plant on cutting productivity and propagation performance. When shoots emerged from underground buds, as compared with axillary buds, the numbers of cuttings and fresh and dry weights of the rooted cuttings were increased by nearly 50%. The promotion of shoot emergence from underground buds on the stock plants led to continuous cutting production for five cycles, with cutting number increasing from 67 to 128 cuttings/plant. Year-round cutting supplies can be achieved by trimming stock plants to the substrate surface to promote juvenile shoot development while maintaining stock plants under long-day photoperiods and warm temperatures (27 °C).
Harvesting labor is the largest annual variable operating expense for apple (Malus ×domestica) orchard enterprises and is subject to escalating costs and shortages. In Europe, much of the cider apple harvesting is done with machinery, greatly reducing production costs. However, despite a rapid increase in hard cider production in North America over the past 15 years, mechanical cider apple harvesting has not been widely implemented. In this study, we compared mechanical with hand harvesting costs for model 5-, 15-, and 60-acre cider apple orchards located in New York using a partial budget model. Scale-appropriate harvesters were identified for use at each farm scale. Sensitivity analyses were used to test the cost differential for using each piece of machinery on varying orchard sizes and to model changes in labor costs. Across all orchard scales, we found that mechanically harvesting cider apples was more profitable than hand harvesting, with larger operations breaking even sooner and realizing greater returns than operations using hand harvesting. Mechanical harvesting costs broke even with hand harvesting in years 16, 7, and 5 and by year 30 reduced cumulative harvesting costs by 23%, 52%, and 53% in our 5-, 15-, and 60-acre model orchards, respectively. Increasing the orchard size resulted in greater returns from mechanical harvesting. Using the machinery in the 15-acre orchard scenario on a 30-acre farm resulted in costs breaking even with hand harvesting in year 3; by year 30, the cumulative costs resulted in 66% lower harvesting costs than hand labor. Mechanical harvesting remained profitable when labor wages were decreased and became more profitable in scenarios with increasing wages. For example, in the 60-acre orchard, mechanical harvesting cost 41% less than hand harvesting with a 2% annual compounding decrease in labor wages; with 2% annual compounding increase in labor wages, the mechanical harvesting cost was 63% less than hand harvesting. In addition to the cost savings, mechanical harvesting allows for harvesting cider apples with fewer logistical challenges, such as contracting, housing, and transporting migrant labor.
Strawberry (Fragaria ×ananassa) is grown during the winter months in subtropical southern Florida and must thrive in higher than average temperatures and limestone soils. This is the first strawberry cultivar trial in southern Florida to include ‘Florida Beauty’, ‘Florida Brilliance’, ‘Strawberry Festival’, ‘Florida Radiance’, ‘Sensation FL127’, and ‘Winterstar’. Overall, ‘Strawberry Festival’ and ‘Sensation FL127’ were the top yielding cultivars, with the highest average total yields of 0.7 and 0.8 kg/plant fresh fruit, respectively. ‘Sensation FL127’ had a 36% greater late-season marketable yield compared with ‘Strawberry Festival’. ‘Sensation FL127’ consistently had the greatest soluble solids content (7.6% to 8.7%). Overall, this study demonstrates significant differences in yield and fruit quality among the cultivars tested in southern Florida.
Courses are the main source of data analysis training for students. The statistical software training taught in those courses can affect student career readiness. However, lack of information about statistical software use in horticulture leads students and mentors to select statistics courses based on course availability and/or anecdotal evaluations. This research aimed to describe statistical software use trends in horticulture research to inform student course selection. We surveyed ≈50% of all articles published in HortScience, HortTechnology, and the Journal of the American Society for Horticultural Science (JASHS) between 2005 and 2020. We found that SAS, SPSS, and R were the most frequently used software packages in this period. SAS use frequency decreased in HortScience and JASHS, but not in HortTechnology. SPSS use increased in JASHS and R use increased in all journals. Results from this retrospective survey suggest that training in SAS, SPSS, and R can help align students with horticulture research practices.
Watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] growers choose transplanting dates every year considering multiple risk factors. Earlier harvests linked to earlier planting typically find more favorable markets, but earlier planting has higher risk of freeze damage. Research also indicates that risk of fusarium wilt (caused by Fusarium oxysporum f. sp. niveum) is higher during cooler weather, adding to the risk of planting earlier. Thus, growers need to balance market risk (e.g., getting a low price) and production risk (e.g., lower harvest or higher cost due to freezing temperatures or disease) in selecting a planting date. The objective of this analysis is to examine the effect of planting date on the distribution of potential economic returns and evaluate whether late planting could be a favorable risk-management strategy. Probability distributions are estimated for key risk factors based on input from watermelon growers, published price data, historical freeze data, experiment station trials, and expert discussions. The distribution of economic returns is then simulated for three planting windows (early, middle, and late) using simulation software. Results demonstrate planting date risk–return tradeoffs and indicate that late planting is unlikely to be preferable to middle planting, even when risk of fusarium wilt is high.
During the 2021 American Society for Horticultural Science annual conference, the Teaching Methods Professional Interest Group hosted the workshop “Going beyond Zoom: Tips and tricks for teaching horticulture online.” This workshop provided a forum for the dissemination of tools, materials, and approaches used to facilitate active learning in horticulture courses. Here we summarize the topics presented in the workshop as a resource for current and future horticulture instructors.
Growers need reliable information on costs and returns they can expect for a cider apple (Malus ×domestica) orchard suitable for mechanization because specialty cider apples can only be used for making cider, and returns are expected to be lower than for fresh table apples. This study estimates the costs, returns, and net profit that growers may realize by planting cider apples in either a freestanding or tall spindle system that use a mechanical harvester (both systems) and mechanical hedger (tall spindle system only). Results show that both production systems have positive net returns during full production, and their respective break-even returns are lower than the current market price, demonstrating that both systems are potentially profitable investments. Results also show that the tall spindle system is potentially more profitable due to the advantages of earlier start of fruiting and higher crop yield. The estimated net returns of the tall spindle system during full production are nearly 4 times higher than that of a freestanding system. At a discount rate of 10%, the net present value (NPV) of the tall spindle system is positive and payback period is 13 years, whereas the NPV of the freestanding system is negative. The discount rate represents the time value of money and reflects the perception of risk for the investment. The break-even discount rates (i.e., NPV = 0) are ≈6.88% for the freestanding system and 10.78% for the tall spindle system. Sensitivity scenarios found that when all else was constant, profitability increased as market price, crop yield, and production area increase and also when the cost of the harvester decreased. Because mechanical harvesters are expensive, profitability tends to be more favorable for larger farms due to economies of scale. Also, a high picking efficiency is important because fruit that falls on the ground is considered crop yield loss and reduces the gross income from cider apples.