Northern Field Production of Leaf and Romaine Lettuce using a High Tunnel

A high tunnel environment was evaluated for production of leaf (`Two Star') and romaine (`Parris Island Cos') lettuce (Lactuca sativa) in a northern location (lat. 64°49'N). Ten plantings were made 1 week apart from May to August. Averaged over the season, the air temperature was 1.5 °C and the soil 0.8 °C higher in the high tunnel than the field. `Two Star' planted on 3 Aug. and harvested on 16 Sept. produced higher yield (P < 0.001) in the tunnel. Head weight was 195 ± 12 g in the tunnel and 99 ± 8 g in the field. For the 13 July-planted `Two Star' lettuce, the field produced significantly (P < 0.001) more at 202 ± 21 g/head than the 135 ± 29 g/head in the tunnel. The three consecutive field plantings of 1, 8, and 15 June resulted in higher `Parris Island Cos' yields than corresponding plantings in the high tunnel. Head weights for harvests on 11, 18, and 25 July were 457 ± 60, 476 ± 65, and 478 ± 25 g under field conditions and 354 ± 46, 331 ± 52, and 312 ± 14 g in the high tunnel. `Two Star' was observed less prone to bolting than `Parris Island Cos'. Although a high tunnel did not generally support increased productivity in this study, the added protection resulted in high quality lettuce with limited necessary preparation and marketing loss in comparison to the field-grown lettuce.

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Effects of Three Production Systems on Muskmelon Yield and Quality in New England

HortScience ◽

10.21273/hortsci.51.5.510 ◽

2016 ◽

Vol 51 (5) ◽

pp. 510-517 ◽

Cited By ~ 4

Author(s):

Mina Vescera ◽

Rebecca Nelson Brown

Keyword(s):

New England ◽

Open Field ◽

Air Temperature ◽

Production System ◽

Production Systems ◽

High Tunnel ◽

High Tunnels ◽

Low Tunnels ◽

Tunnel System ◽

Field Production

Muskmelons (Cucumis melo L.) are routinely grown on black plastic mulch, as the associated increase in soil temperatures, more stable soil moisture, and decreased weed competition result in higher yields than in bare soil production. However, mulch does little to moderate air temperature, which can be below optimum for melon production under New England conditions. One option for increasing air temperature is to grow plants in unheated hoophouses, or high tunnels. Another option is to use low tunnels consisting of ventilated clear plastic rowcovers supported over wire hoops. This study compared low tunnels and high tunnels to open field production for muskmelon production in a peri-urban market farm system in Rhode Island. Five hybrid muskmelon cultivars were grown for 2 years to compare earliness, yield, and fruit quality among the three production systems. Both tunnel systems increased the rate at which growing degree-days (GDD) accumulated relative to open field production, and resulted in statistically significant differences in starting date of first harvest, with fruit in the high tunnel treatment ripening first. The high tunnel production system increased yields per hectare in both years relative to the other production systems due to increased planting density, but not due to increased yields per plant. Marketable yields per hectare from the high tunnel system significantly exceeded those from the open field for four out of the five cultivars in 2011, but for only one out of five cultivars in 2012. Marketable yields from the low tunnel system were ≈10% higher than the open field in 2011, and almost double the open field yields in 2012. Fruit from the low tunnels had the highest concentration of soluble solids in both years. The high tunnel production system did not increase yields sufficiently to offset the associated increase in costs of production, suggesting that muskmelon is not a good crop for high tunnel production in New England. In contrast, a yield increase of only 15% would be sufficient to offset the increased costs of employing the low tunnel production system. Low tunnels have the potential to greatly benefit muskmelon production in New England, particularly in years or locations where GDD accumulate slowly.

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Anesthetic effects of ketamine–medetomidine–hydromorphone in dogs during high-quality, high-volume surgical sterilization program under field conditions

Veterinary Anaesthesia and Analgesia ◽

10.1016/j.vaa.2020.08.001 ◽

2020 ◽

Vol 47 (6) ◽

pp. 789-792

Author(s):

François R. Sylvestre ◽

Beatriz P. Monteiro ◽

Marie-Josée Simard ◽

Paulo V. Steagall

Keyword(s):

High Volume ◽

Field Conditions ◽

High Quality ◽

Surgical Sterilization

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Isolation and Molecular Characterization of the Romaine Lettuce Phylloplane Mycobiome

Journal of Fungi ◽

10.3390/jof7040277 ◽

2021 ◽

Vol 7 (4) ◽

pp. 277

Author(s):

Danny Haelewaters ◽

Hector Urbina ◽

Samuel Brown ◽

Shannon Newerth-Henson ◽

M. Catherine Aime

Keyword(s):

Lactuca Sativa ◽

New Combinations ◽

Food Spoilage ◽

Human Pathogens ◽

Plant Leaves ◽

Romaine Lettuce ◽

Future Studies ◽

The Core ◽

American Agriculture

Romaine lettuce (Lactuca sativa) is an important staple of American agriculture. Unlike many vegetables, romaine lettuce is typically consumed raw. Phylloplane microbes occur naturally on plant leaves; consumption of uncooked leaves includes consumption of phylloplane microbes. Despite this fact, the microbes that naturally occur on produce such as romaine lettuce are for the most part uncharacterized. In this study, we conducted culture-based studies of the fungal romaine lettuce phylloplane community from organic and conventionally grown samples. In addition to an enumeration of all such microbes, we define and provide a discussion of the genera that form the “core” romaine lettuce mycobiome, which represent 85.5% of all obtained isolates: Alternaria, Aureobasidium, Cladosporium, Filobasidium, Naganishia, Papiliotrema, Rhodotorula, Sampaiozyma, Sporobolomyces, Symmetrospora and Vishniacozyma. We highlight the need for additional mycological expertise in that 23% of species in these core genera appear to be new to science and resolve some taxonomic issues we encountered during our work with new combinations for Aureobasidiumbupleuri and Curvibasidium nothofagi. Finally, our work lays the ground for future studies that seek to understand the effect these communities may have on preventing or facilitating establishment of exogenous microbes, such as food spoilage microbes and plant or human pathogens.

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Ambient Air Temperature Assisted Crystallization for Inorganic CsPbI2Br Perovskite Solar Cells

Molecules ◽

10.3390/molecules26113398 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3398

Author(s):

Yi Long ◽

Kun Liu ◽

Yongli Zhang ◽

Wenzhe Li

Keyword(s):

Solar Cells ◽

Air Temperature ◽

High Performance ◽

Defect Density ◽

Perovskite Solar Cells ◽

Ambient Air ◽

Dark Phase ◽

High Quality ◽

Ambient Air Temperature ◽

Air Atmosphere

Inorganic cesium lead halide perovskites, as alternative light absorbers for organic–inorganic hybrid perovskite solar cells, have attracted more and more attention due to their superb thermal stability for photovoltaic applications. However, the humid air instability of CsPbI2Br perovskite solar cells (PSCs) hinders their further development. The optoelectronic properties of CsPbI2Br films are closely related to the quality of films, so preparing high-quality perovskite films is crucial for fabricating high-performance PSCs. For the first time, we demonstrate that the regulation of ambient temperature of the dry air in the glovebox is able to control the growth of CsPbI2Br crystals and further optimize the morphology of CsPbI2Br film. Through controlling the ambient air temperature assisted crystallization, high-quality CsPbI2Br films are obtained, with advantages such as larger crystalline grains, negligible crystal boundaries, absence of pinholes, lower defect density, and faster carrier mobility. Accordingly, the PSCs based on as-prepared CsPbI2Br film achieve a power conversion efficiency of 15.5% (the maximum stabilized power output of 15.02%). Moreover, the optimized CsPbI2Br films show excellent robustness against moisture and oxygen and maintain the photovoltaic dark phase after 3 h aging in an air atmosphere at room temperature and 35% relative humidity (R.H.). In comparison, the pristine films are completely converted to the yellow phase in 1.5 h.

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Effect of Methyl Jasmonate on Phenolic Compounds and Carotenoids of Romaine Lettuce (Lactuca sativa L.)

Journal of Agricultural and Food Chemistry ◽

10.1021/jf071927m ◽

2007 ◽

Vol 55 (25) ◽

pp. 10366-10372 ◽

Cited By ~ 71

Author(s):

Hyun-Jin Kim ◽

Jorge M. Fonseca ◽

Ju-Hee Choi ◽

Chieri Kubota

Keyword(s):

Phenolic Compounds ◽

Methyl Jasmonate ◽

Lactuca Sativa ◽

Romaine Lettuce ◽

Lactuca Sativa L

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Supplemental upward LED lighting for growing romaine lettuce (Lactuca sativa) in a plant factory: cost performance by light intensity and different light spectra

Acta Horticulturae ◽

10.17660/actahortic.2018.1227.79 ◽

2018 ◽

pp. 623-630

Author(s):

S. Saengtharatip ◽

N. Lu ◽

M. Takagaki

Keyword(s):

Light Intensity ◽

Lactuca Sativa ◽

Romaine Lettuce ◽

Cost Performance ◽

Led Lighting ◽

Light Spectra ◽

Plant Factory

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Capturing heat stress induced variability in spikelet sterility using panicle, leaf and air temperature under field conditions

Field Crops Research ◽

10.1016/j.fcr.2015.10.012 ◽

2016 ◽

Vol 190 ◽

pp. 10-17 ◽

Cited By ~ 8

Author(s):

Rajendran Sathishraj ◽

Raju Bheemanahalli ◽

Mahendran Ramachandran ◽

Michael Dingkuhn ◽

Raveendran Muthurajan ◽

...

Keyword(s):

Heat Stress ◽

Air Temperature ◽

Field Conditions ◽

Spikelet Sterility

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Effect Of Agrotechnical Measures And Varieties On Seasonal Dynamics Of Tetranychus Urticae Koch (Acari, Trombidiformes, Tetranychidae) On High Tunnel-Cultivated Garden Strawberries

Proceedings of the Latvian Academy of Sciences Section B Natural Exact and Applied Sciences ◽

10.1515/prolas-2015-0005 ◽

2015 ◽

Vol 69 (1-2) ◽

pp. 45-49

Author(s):

Ineta Salmane

Keyword(s):

Tetranychus Urticae ◽

Air Temperature ◽

Spider Mite ◽

Seasonal Pattern ◽

Plant Cover ◽

Climatic Conditions ◽

Early Season ◽

High Tunnel ◽

Negative Effect ◽

Two Spotted Spider Mite

Abstract The aim of the present study was to determine the seasonal pattern of two-spotted spider mite Tetranychus urticae on strawberries cultivated in polythene-covered high tunnels in temperate climatic conditions. Various cultivars were used and the effect of modification of plant covering indices on abundance and incidence of these mites was also tested. The number of two-spotted spider mites was relatively low at the beginning of the vegetation season and started to increase when average air temperature rose above 20 to 25 °C. In the experiment two types of tunnels differing in additional plant cover were used. The maximum mite abundance did not significantly vary between varieties in tunnel 1 conditions, but it was significantly lower for variety 'Sonata' in tunnel 2 conditions. Mite numbers significantly declined after strawberry foliage mowing and removal of polythene cover. Mite development was prolonged in tunnel 1, where additional cover of plants was used and higher early season air temperature was recorded in comparison to tunnel 2. It was concluded that increase in early season temperature can increase two-spotted spider mite abundance and have a more negative effect on strawberry plants in respect of foliage damage by mites.

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