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A main constraint of hydroponics is the need for high-quality water. This study evaluated the viability of reverse osmosis concentrate backflush, or reject water, as a water source for hydroponic lettuce production. We compared the growth of ‘Casey’ butterhead lettuce produced using nutrient film technique hydroponics with municipal (tap) water (TW), reverse osmosis (RO) water, and reject water from an RO system [wastewater (WW)]. Characterization of water sources showed the following: RO had trace minerals; TW had the greatest potassium (K), calcium (Ca), and magnesium (Mg); and WW had greatest sulfur (S), sodium (Na), and chloride (Cl). No water source had detectable heavy metals. Mineral and heavy metal tissue contents were determined at mid-harvest and end-harvest, and nutrient budgets for nitrogen (N), S, Ca, Mg, Na, and Cl were calculated. Water sources did not impact lettuce growth during the 4-week hydroponic production cycle based on leaf greenness, diameter, fresh weight, or dry weight. In the nutrient reservoirs, Ca and Mg increased over time and were greatest in TW. The Cl and Na levels in WW were 106 and 203 mg·L⁻¹, respectively, and the electrical conductivity (EC) of this treatment increased to 3.5 dS·m⁻¹ after 4 weeks; however, plant water uptake, water use efficiency, and percent moisture loss were unaffected. In shoot tissue, lettuce grown with WW had less Ca at mid-harvest and less Mg at mid-harvest and end-harvest compared with other treatments, suggesting antagonization of uptake by high salt. Tissue S was not different across treatments; however, there were differences in reservoirs of the water sources as S accumulated more from WW. Tissue Na and Cl levels were different among the treatments, and higher amounts in nutrient reservoirs translated to higher uptake by lettuce. Although the heavy metal content in all water sources was <0.01 ppm, arsenic, lead, and chromium were measured in lettuce tissue at levels that exceed recommended limits in most instances. Our results indicated that a water source of RO reject water from municipal feed water is a viable irrigation option for short-term hydroponic production of butterhead lettuce; however, EC reduction in the nutrient solution would be necessary when continuing sequential cropping.

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.

Strawberries (Fragaria ×ananassa) are an important crop for diversified fruit and vegetable farms in the northeastern United States as well as in Ontario and Québec, Canada. The industry in this cold climate region differs greatly from that in the major strawberry-producing states of Florida and California because strawberries typically represent a smaller share of total farm revenue and are sold primarily through retail markets. In recent years, strawberry production and marketing methods in the northeastern United States and Canada have diversified to meet the unique challenges of the region, including regional demand, extended seasons, and management of an increasingly challenging pest and disease complex. In 2020, we distributed an online survey to 163 commercial producers to obtain a snapshot of marketing and production practices used on strawberry-producing farms in this region and to assess research and outreach needs to better serve the industry. We conducted in-depth case study interviews with a small number of producers after the survey. We found that traditional June-bearing strawberry production continues to represent >50% of production, and that most fruit are grown conventionally. Day-neutral strawberry production was reported by an increased number of producers in New York as well as in Canada, and a higher percentage of day-neutral growers, compared to that of June-bearing producers, reported using protected culture. Botrytis (gray mold), weeds, and leaf spots were the top overall pest pressures indicated by growers. Survey respondents preferred written outreach materials and on-farm meetings to obtain information. Integrated pest management, organic production, and cultivar performance were the top priorities for subjects. The survey and interviews also provided information about the most common strategies for winter protection, frequency of pesticide applications, lifespan of plantings, and other current strawberry production practices in the region. Our survey results may be used by researchers and extension professionals to better serve this diversifying industry.

Pumpkin (Cucurbita moschata Duch.) is a versatile crop with strong stress resistance and promising growth potential. Widely cultivated in various regions of China, it ranks among the top crops globally in terms of both planting area and consumption. Known for its pleasant taste and high nutritional value, pumpkin pulp is rich in essential trace elements for the human body. Even after harvest, pumpkin fruit remains metabolically active, requiring its own nutrients to complete the postripening process. Failure to provide proper postharvest storage conditions can lead to excessive water loss and rapid nutrient depletion, resulting in rough, shriveled, and even rotten peel, ultimately diminishing the economic value of the pumpkin. This study aimed to investigate the changes in pumpkin quality and physiological indicators during storage to provide insights to determine optimal consumption and processing periods of pumpkins. The pumpkins were stored at a temperature of 16 ± 2 °C and 60% to 80% humidity during the experiment. The dynamic changes in fruit quality, hardness, respiration rate, malondialdehyde content, level of antioxidant enzymes, and other indicators of two pumpkin cultivars (BM5 and JQ) were assessed during storage, and the correlation among these indicators was evaluated. The results indicated a decrease in the vitamin C content and pulp hardness, whereas the superoxide dismutase and catalase contents initially increased and then decreased, and malondialdehyde and weight loss rates increased over the storage period. The weight loss rate exhibited significant positive and negative correlations with the malondialdehyde content (P < 0.01) of the two cultivars, whereas the vitamin C content showed a significant positive correlation with pulp hardness (P < 0.01). The findings indicate that optimal fruit quality was maintained within 40 days of postharvest storage. This study provides valuable insights into the selection of storable pumpkin cultivars.

To investigate factors influencing the seed germination of Sichuan pepper (Zanthoxylum armatum DC.) and determine the optimal germination method, this study used an L₁₆(4³) orthogonal test. The effects of compound treatments, including 2.5% sodium carbonate degreasing time, indole acetic acid (IAA) concentration, and IAA soaking time on seed germination were examined. The results indicated that 2.5% sodium carbonate degreasing time was the primary factor affecting the germination rate and vigor index of the seeds. IAA concentration primarily affected the germination index and the duration of germination, whereas IAA soaking time primarily influenced the time lag of germination. In addition, the 2.5% sodium carbonate degreasing time had a significant effect on the germination rate; IAA concentration significantly impacted the germination index; and IAA soaking time had a significant effect on both the germination index and the time lag of germination. Through the analysis and evaluation of the membership function, the optimal treatment combinations for seed germination were determined to be a 24-hour degreasing time with 2.5% sodium carbonate, an IAA concentration of 200 mg·L⁻¹, and an IAA soaking time of 12 hours. This study provides a valuable reference for the future propagation of Zanthoxylum armatum DC.

The objective of this study was to evaluate the effect of fertilizer application and photosynthetic photon flux density (PPFD) on shoot and root growth of chrysanthemum (Chrysanthemum indicum) and begonia (Begonia ×hiemalis) cuttings. During an acclimation phase indoors, unrooted cuttings were treated with a complete fertilizer solution (15N–2.2P–12.5K with micronutrients) that provided 100 mg·L⁻¹ nitrogen or with tap water. Cuttings were placed under PPFDs of 70 or 140 µmol·m⁻²·s⁻¹ provided by broadband white light-emitting diode fixtures. A finishing phase in a greenhouse was conducted to evaluate carryover treatment effects. Fertilizer application had minimal effects on cuttings during both the acclimation and finishing phases. However, the higher PPFD increased shoot dry weight (DW) in both species and produced shorter chrysanthemum cuttings with almost double the root DW and higher chlorophyll concentration than those under the lower PPFD. During the finishing phase, chrysanthemum cuttings that had been acclimated under the higher PPFD produced 9% and 14% more shoot and root DW, respectively, than those under the lower PPFD, but no treatment differences were measured for begonia. Overall, our results suggest that when there is a fertilizer starter charge present in the substrate, additional fertilizer application during indoor acclimation will not affect shoot and root growth of chrysanthemum and begonia cuttings under conditions similar to those used in our study. Furthermore, cuttings of high-light-requiring species such as chrysanthemum are more likely to benefit from higher PPFD during indoor acclimation than those that require less light such as begonia.

Indiana cultivates approximately 7000 acres of watermelons (Citrullus lanatus) every year, with the majority of production concentrated in southern Indiana, thus making this region a key area for watermelon production in the United States. Diverse irrigation and fertilization practices are used for watermelon production in the region, yet their effects on production outcomes remain poorly understood. To address this knowledge gap, this study investigated the impact of existing practices on watermelon yield to optimize irrigation and fertilization practices for improved production. The experiment was conducted at the Southwest Purdue Agricultural Center, Vincennes, IN, USA, during the 2022 and 2023 watermelon seasons. The following four treatments were applied: high irrigation, low irrigation, no irrigation, and fertigation. The fertigation treatment received the same water application as the high irrigation treatment, but with frequent fertilizer application with irrigation; however, fertilizers were applied before planting in the high, low, and no irrigation treatments. Although soil moisture levels at the different depths varied notably among treatments, no significant differences in yield by weight were observed. The minimal impact of irrigation on watermelon yield suggested that sufficient water is stored in the soil to prevent yield-reducing stress during dry periods. However, the high irrigation and fertilization treatments produced more fruit than the low irrigation and no irrigation treatments. The dry periods during both years coincided with the watermelon fruit-setting stages, potentially contributing to the lower fruit set in the low irrigation and no irrigation treatments. Fertigation showed a higher early yield in 2022 than that of the other treatments. An analysis of soil and tissue nitrogen levels indicated that solely applying nitrogen before planting could lead to excessive soil nitrogen during vegetative growth. This excess nitrogen might delay flowering and harvest. This project offers insights into enhancing irrigation and fertilization practices for watermelon production in southern Indiana, provides recommendations, and discusses future research directions.

Production of attractive and water-efficient plants native to the plains and prairies of central North America can sometimes be limited because of problems associated with successful rooting of vegetative cuttings. Winecups (Callirhoe involucrata) is an attractive native plant, valued for its long period of bloom, drought tolerance, and winterhardiness, but can be difficult to propagate from seeds and vegetative cuttings. Seed dormancy issues can result in unreliable germination and seedling variations, which reduces crop uniformity. Although propagation from rooted cuttings maintains crop uniformity, cuttings often fail to root or root poorly. Manipulating the growing conditions of stock plants to suppress reproductive growth may improve rooting success of vegetative cuttings. Based on research conducted earlier with other ornamental perennials and programmed photoperiods, winecups plants were grown under three programmed photoperiods to determine if a particular photoperiod could be used to suppress reproductive growth and promote vegetative growth. The study consisted of three experiments, all conducted in similar fashion but at different times during the year. Results indicate that plants grown under 10-hour and 8-hour photoperiods remained vegetative longer when compared with plants grown under 12-hour photoperiod. Vegetative cuttings harvested from plants grown under 8-hour photoperiod had higher percent rooting when compared with vegetative cuttings harvested from plants grown under 10-hour and 12-hour photoperiods. Based on the findings from this research, plant propagators may be able to increase production of winecups by growing stock plants under 8-hour photoperiod.

Day-neutral strawberry (DNS) production is increasing in the Upper Midwest because of its extended harvest season and greater yield over June-bearing cultivars. However, the longer season increases fruit exposure to the invasive spotted-wing drosophila (Drosophila suzukii; SWD), which threatens the production of small fruits and berries, particularly in organic systems. Numerous pest management tactics have been developed for SWD in recent years; however, relatively few studies have investigated the impact of SWD on DNS. Organic DNS growers need information regarding which management strategy is most effective when compared directly. To address this knowledge gap, we established a 2-year controlled field experiment with organic DNS. We applied treatments that correspond with techniques that local growers reported using or that have shown promise for organic raspberries, including increased harvest frequency, botanical-based repellents, and weekly rotations of organic insecticides, which we compared with an untreated control. We hypothesized that noninsecticidal SWD management strategies would result in fewer SWD eggs per berry and a lower proportion of infested berries compared with those associated with an untreated control. We also hypothesized that noninsecticidal management strategies would be as effective and cost less than organic insecticide applications. We collected data regarding labor hours, direct costs, strawberry yield, and SWD infestation in experimental plots on certified organic land in Minnesota in 2022 and 2023. An average of 33% of strawberries contained SWD eggs. The experimental treatments showed inconsistent effectiveness for reducing infestation compared with that of the untreated control plots and had no effect on marketable plant yield over the 2-year period. Thus, the added labor expense of these pest control treatments yielded net returns that were 17% to 21% below the control. Labor-saving alternatives like exclusion netting or postharvest cold treatments, which reduce fruit pest exposure and egg viability without harming nontarget insects, may offer more cost-effective solutions for managing SWD in organic DNS.