Search Results (7)

Biodegradable mulch films (BDMs) have emerged as a promising alternative to conventional polyethylene (PE) films in modern horticulture, yet the effect of film thickness on crop performance remains inadequately understood. In this study, a two-year field experiment (2023–2024) under protected cultivation was conducted to evaluate BDMs with thicknesses (0.006, 0.008, and 0.010 mm) for watermelon production in Beijing, China. The results showed that all BDMs enhanced soil temperature and moisture compared to bare soil (main effect of mulching, p < 0.05) and significantly influenced soil available nitrogen (p < 0.05), while other soil properties were less affected. Year effects were generally not significant, reflecting the stable microclimatic conditions under hoop-house cultivation. Mechanical property assessments indicated substantial declines in tensile load, tensile strength, and elongation at break after field use, especially for thinner films. Notably, Bio-0.006 and Bio-0.008 significantly improved fruit weight and soluble sugar content relative to PE (p < 0.05), leading to higher yields and better commercial quality. These results suggested that appropriately thin BDMs can satisfy agronomic requirements for watermelon under protected cultivation while minimizing plastic residues, offering a practical basis for optimizing biodegradable film thickness to balance mulching performance, productivity, and environmental sustainability. Full article

Dragon fruit or pitaya (Hylocereus sp.) is an exotic tropical plant gaining popularity in the United States as it is a nutrient-rich fruit with mildly sweet flavor and a good source of fiber. Although high tunnels are being used to produce specialized crops, little is known about how pitaya growth, physiology and nutrient uptake change throughout the production period. This study aims to evaluate the impact of high tunnels and varying rates of vermicompost on three varieties of pitaya, White Pitaya (WP), Yellow Pitaya (YP), and Red Pitaya (RP), to assess the soil and plant nutrient dynamics, spectral reflectance changes and plant growth. Plants were assessed at 120 and 365 DAP (Days After Plantation). YP thrived in a high tunnel compared to an open environment in terms of survival before 120 DAP, with no diseased incidence and higher nutrient retention. The nutrient accumulation in the RP, WP, and YP shoot samples 120 DAP were ranked in the following order, K > N > Ca > Mg > P > Fe > Zn > B > Mn, while 365 DAP, they were ranked as K > Ca > N > Mg > P > S > Fe > Zn > B > Mn. The nutrient accumulation in the RP, WP, and YP, soil samples 120 and 365 DAP were ranked in the following order: N > Ca > Mg > P > K > Na > Zn. Soil nutrients showed a higher concentration of Na and K grown inside the high tunnels in all three pitaya species due to the increased concentration of soluble salts. Spectral reflectance analysis showed that RP and WP had higher reflectance in the visible and NIR region compared to YP due to their higher plant biomass and canopy cover. This study emphasizes the importance of environmental conditions, nutrition strategies, and plant physiology in the different pitaya plant species. The results suggest that high tunnels with appropriate vermicompost can enhance pitaya growth and development. Full article

Tigernut or ‘chufa’ (Cyperus esculentus L. var. sativus) is gaining popularity in the United States as a high energy tuber crop known for sweet and chewy taste, 40–45% gluten-free digestible carbohydrate, high dietary fiber content, healthful fatty acid profile (73% monounsaturated, 18% saturated, 9% polyunsaturated—similar to olive oil), high oleic acid, and high P, K, and vitamins C. E. Tigernut tubers were obtained from specialty crop markets in central NJ and purchased online from commercial distributors as propagules for transplants for hoop house and field production studies. Nine tigernut selections were also evaluated under NJ hoop house culture conditions for growth habit and in the field for adaptation and productivity We concluded that tigernut production is feasible in NJ based on the results of these experiments. The growth patterns of three selections (GH, MV and SK) were studied and characterized. Foliage growth was similar in the three selections. Plant height ranged from an average of 90 cm in GH to 110 cm in MV and SK; side shoot production capacity ranged from 13 shoots per propagule in GH to 20 or more in MV and SK over 14 weeks. Over 99% of tubers in MV and SK were located within the upper 5 cm of the growth media (Pro-Mix BX brand) but tubers of GH were observed at greater soil depths (~20 cm). Tubers varied from spherical (round) in shape in GH and SK to oblong (elongated) in MV. In the field the best growth and tuber yields from NG3 and T-USA selections were obtained under black or white-over-black plastic mulch in conventionally managed plots. Tubers showed high levels of Fe (168–218 ppm) and Zn (39–50 ppm) implying that they should be a good source of these essential elements in human diet. Studies also showed that the tigernut tuber cannot survive the cold winter months in the field in NJ, therefore minimizing the fear of “tigernut invasion” of agronomic fields in NJ and similar agroecosystems. Full article

Leafy green production in high tunnels (HTs) results in increased yields, improved visual quality, and extended production with polyethylene (poly) film and/or shade cloth coverings. However, altering visible and ultra-violet light with HT coverings may reduce phytochemicals, thus influencing plant pigmentation and taste. The objective of this study was to examine various HT coverings on the sensory perceptions, soil temperature, color, and anthocyanin accumulation of red leaf lettuce. The coverings included standard poly, standard poly with removal two weeks prior to harvest (movable), diffuse poly, clear poly, UV-A/B blocking poly (block), standard poly with 55% shade cloth, and the open field. A highly trained descriptive panel evaluated the samples using a scale from 0 (none) to 15 (extremely high) and determined a list of 20 sensory attributes. The color intensity attribute had the most differentiation between coverings, and the open field was higher (i.e., darker) than the others at 7.5 (p < 0.0001), followed by clear and movable coverings at 6.8, and the shade covering scored a 2. Strong relationships existed between both colorimetric (hue°) and anthocyanin analysis to panelist-based scores (R² = 0.847 and 0.640, respectively). The initial crispness was similar for movable, standard, diffuse, and block coverings at 5.3 on average, which was higher than the open field at 4 (p < 0.01). The open field lettuce grew under cooler soil temperatures, which may have slowed down maturation and resulted in softer tissue. Based on this study, HT growers can implement specific coverings to cater to markets that value visual quality. Full article

Wheat is a major cool-season forage crop in the southern United States. The objective of this study is to understand the effect of nitrogen (N) fertilization on wheat biomass yield, quality, nitrogen use efficiency (NUE), and nitrogen nutrition index (NNI). The experiments were conducted in a greenhouse and a hoop house in a split-plot design, with three replications. Twenty wheat cultivars/lines were evaluated at four N rates (0, 75, 150, and 300 mg N.kg⁻¹ soil) in the greenhouse and (0, 50, 100, and 200 mg N.kg⁻¹ soil) in the hoop house. In general, high-NUE lines had lower crude protein content than the low-NUE lines. None of the cultivars/lines reached a plateau for biomass production or crude protein at the highest N rate. The line × N rate interaction for NUE was not significant in the greenhouse (p = 0.854) but was highly significant in the hoop house (p < 0.001). NNI had a negative correlation with NUE and biomass. NUE had strong positive correlations with shoot biomass and total biomass but low to moderate correlations with root biomass. NUE also had a strong positive correlation with N uptake efficiency. Lines with high NUE can be used in breeding programs to enhance NUE in wheat for forage use. Full article

(1) Background: We assessed the impact of high tunnel coverings and harvest maturity (breaker and light red) on antioxidant capacity, ascorbic acid (AsA), lycopene, β–carotene, and phenolic compound (flavonoid and phenolic acid) accumulation in tomatoes (Solanum lycopersicum) at harvest and postharvest. (2) Methods: The two-year study in Olathe, KS, included six different coverings: a standard polyethylene (standard poly), diffuse poly (diffuse), clear poly (clear), UV-A/UV-B blocking poly (block), 55% shade cloth + standard poly (shade), and removal of standard poly two weeks prior to harvest (movable). (3) Results: Antioxidant capacity increased in fruit grown under the clear covering, compared to the shade covering (p < 0.05); similarly, AsA accumulation increased under the standard and clear coverings, relative to the movable and shade coverings (p < 0.001). Postharvest, at the point of consumption (POC), rutin increased in fruit harvested at light red stage versus breaker stage (p < 0.001), and chlorogenic acid increased in light red harvested fruit by 60% under movable, 55% under shade, and 43% under block covering than breaker harvested fruit (p < 0.01). (4) Conclusions: Based on these results, we conclude that both high tunnel covering and postharvest maturation alter antioxidant capacity, AsA, lycopene, and phenolic compound accumulation profiles by the POC. Full article

The majority of heat released during composting is contained in latent form of water vapour. To improve the rate of heat recovery, a simple heat exchanger based on condensation of compost vapours was designed. A prototype of this condenser-type heat exchanger was built and tested as a part of pilot-scale compost heat recovery system. Passively aerated static pile (modified Jean Pain mound) with enhanced aeration using vertical channels was chosen for this composting experiment. Insulation of the compost mound and adjacent hoop house further improved the efficiency of the heat recovery and utilization. Full article