scholarly journals Intercropping Winter Greens between Blackberry Rows for Year-round High Tunnel Production

2020 ◽  
Vol 30 (1) ◽  
pp. 47-54
Author(s):  
Jacqueline Cormier ◽  
Robert Heyduck ◽  
Steven Guldan ◽  
Shengrui Yao ◽  
Dawn VanLeeuwen ◽  
...  
Keyword(s):  
Spinacia Oleracea ◽  
Field Trials ◽  
Yield Data ◽  
High Tunnel ◽  
Row Covers ◽  
Air Temperatures ◽  
Significant Difference ◽  
Adjacent Field ◽  
Temperature Damage ◽  
Thornless Blackberry

A decrease in available farmland worldwide has prompted interest in polyculture systems such as intercropping where two or more crops are grown simultaneously on the same land to increase the yield per farm area. In Alcalde, NM, a year-round intercropping system was designed to evaluate organically produced blackberry cultivars (Rubus, subgenus Rubus) and winter greens in a high tunnel over a 2-year period. Two floricane fruiting blackberry cultivars, Chester Thornless and Triple Crown, were grown intercropped with ‘Red Russian’ kale (Brassica napus) and ‘Bloomsdale’ spinach (Spinacia oleracea) in a high tunnel. In an adjacent field, the planting of blackberry was repeated with no winter intercrop and no high tunnel. Both cultivars of blackberry were harvested July to September, and fresh weights were measured to determine suitability to the intercropping system in the high tunnel. Both species of winter greens were harvested January to April, and fresh yield weights were measured to discern fitness as possible intercrops in this system. Row covers were used for kale and spinach, and air temperatures were monitored November to April inside the high tunnel. High tunnel temperatures were within acceptable ranges for the production of greens with the use of rowcovers. Yield data from this study indicates that ‘Triple Crown’ blackberry outperformed ‘Chester Thornless’ blackberry in both the high tunnel and field trials with significant difference in the second season. Additionally, blackberry yields from both cultivars were observed to be higher in the field than in the high tunnel for both years. High temperature damage to high tunnel berry canes was noticed for both cultivars, with observed yield decreases in the second year in the high tunnel. Overall, this study indicates that the phenology and climate needs of the two winter greens and blackberry cultivars were not compatible for sustaining year-round organic high tunnel production.

scholarly journals Yield of Leafy Greens in High Tunnel Winter Production in the Northwest United States

HortScience ◽  
2013 ◽  
Vol 48 (2) ◽  
pp. 183-188 ◽  
Author(s):  
Kristy Borrelli ◽  
Richard T. Koenig ◽  
Brad M. Jaeckel ◽  
Carol A. Miles
Keyword(s):  
Spinacia Oleracea ◽  
Planting Date ◽  
Temperate Climate ◽  
High Tunnel ◽  
Leafy Greens ◽  
Air Temperatures ◽  
Cropping Season ◽  
High Tunnels ◽  
Season Extension ◽  
Cold Tolerant

Season extension structures like high tunnels make it possible to produce cold-tolerant crops during winter months for both a longer cropping season and a winter market season. The effects of location and planting date on the fresh yield of several cultivars of Asian greens (Brassica rapa L.), lettuce (Lactuca sativa L.), and spinach (Spinacia oleracea L.) were examined at Moscow, ID/Pullman, WA, and Vancouver, WA, a cold temperate climate and a mild marine climate, respectively. In Winter 2005–06, 20 cultivars were evaluated and in Winter 2006–07 a subset of 12 cultivars were evaluated. Location impacted yield, and higher yields overall were attained at Vancouver than at Moscow/Pullman, likely as a result of more consistent, warmer soil and air temperatures as well as increasing irradiance in February and March at Vancouver. Asian green cultivars had the highest overall yield resulting from faster growth compared with spinach and lettuce cultivars at both locations. Although most lettuce cultivars grew throughout the winter, further research is needed to identify the most suitable cultivars, seeding dates, and planting densities to optimize winter production of this crop and for Asian greens and spinach. Planting date influenced yields with the highest yields obtained for the third planting date for all trials except at Moscow/Pullman in the second year. Overall, this research suggests that it is possible to grow many cold-tolerant cultivars of Asian greens, spinach, and lettuce in a high tunnel during the winter months in both mild and cold temperate northern climates.

scholarly journals Impact of Shade and Fogging on High Tunnel Production and Mineral Content of Organically Grown Lettuce, Basil, and Arugula in Georgia

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 625
Author(s):  
Savanah Laur ◽  
Andre Luiz Biscaia Ribeiro da Silva ◽  
Juan Carlos Díaz-Pérez ◽  
Timothy Coolong
Keyword(s):  
Mineral Content ◽  
Planting Date ◽  
High Tunnel ◽  
Lactuca Sativa L ◽  
Air Temperatures ◽  
Shade Cloth ◽  
High Tunnels ◽  
Soil Temperatures ◽  
Organically Grown ◽  
The Impact

This study evaluated the impact of shade cloth and fogging systems on the microclimate at the plant canopy level and yield of basil (Oscimum basilicum L.), arugula (Eruca vesicaria subsp. Sativa L.), and lettuce (Lactuca sativa L.) planted in mid-September and early October in high tunnels. Fogging systems were installed at canopy level in plots within shaded (30%) and non-shaded high tunnels. Average air temperatures in the shaded high tunnels were 0.9 °C lower than non-shaded high tunnels during the day. Shade cloth significantly reduced soil temperatures during the day and night periods by 1.5 °C and 1.3 °C, respectively, compared to non-shaded treatments. Fogging systems did not have an impact on air temperature, soil temperature, or relative humidity, but did increase canopy leaf wetness. Shade and fogging did not impact the yield of any of the crops grown. Yield was impacted by planting date, with earlier planting result in higher yields of lettuce and basil. Yields for arugula were greater during the second planting date than the first. Planting date and shade cloth interacted to affect the concentrations of macronutrients.

scholarly journals The Street Air Warming Phenomenon in a High-Rise Compact City

Atmosphere ◽  
2018 ◽  
Vol 9 (10) ◽  
pp. 402 ◽  
Author(s):  
Xiaoxue Wang ◽  
Yuguo Li ◽  
Xinyan Yang ◽  
Pak Chan ◽  
Janet Nichol ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Thermal Environment ◽  
Urban Climate ◽  
Pollutant Dispersion ◽  
Urban Morphology ◽  
Air Temperatures ◽  
Significant Difference ◽  
Sensitivity Studies ◽  
Weather Stations

The street thermal environment is important for thermal comfort, urban climate and pollutant dispersion. A 24-h vehicle traverse study was conducted over the Kowloon Peninsula of Hong Kong in summer, with each measurement period consisting of 2–3 full days. The data covered a total of 158 loops in 198 h along the route on sunny days. The measured data were averaged by three methods (direct average, FFT filter and interpolated by the piecewise cubic Hermite interpolation). The average street air temperatures were found to be 1–3 °C higher than those recorded at nearby fixed weather stations. The street warming phenomenon observed in the study has substantial implications as usually urban heat island (UHI) intensity is estimated from measurement at fixed weather stations, and therefore the UHI intensity in the built areas of the city may have been underestimated. This significant difference is of interest for studies on outdoor air temperature, thermal comfort, urban environment and pollutant dispersion. The differences were simulated by an improved one-dimensional temperature model (ZERO-CAT) using different urban morphology parameters. The model can correct the underestimation of street air temperature. Further sensitivity studies show that the building arrangement in the daytime and nighttime plays different roles for air temperature in the street. City designers can choose different parameters based on their purpose.

scholarly journals Improving the precision of genotype selection in wheat performance trials

2013 ◽  
Vol 13 (4) ◽  
pp. 234-240 ◽  
Author(s):  
Giovani Benin ◽  
Lindolfo Storck ◽  
Volmir Sérgio Marchioro ◽  
Francisco de Assis Franco ◽  
Ivan Schuster ◽  
...  
Keyword(s):  
Grain Yield ◽  
Field Trials ◽  
Adjustment Coefficient ◽  
Experimental Accuracy ◽  
Yield Data ◽  
Yield Performance ◽  
Wheat Genotypes

The aim of this study was to verify whether using the Papadakis method improves model assumptions and experimental accuracy in field trials used to determine grain yield for wheat lineages indifferent Value for Cultivation and Use (VCU) regions. Grain yield data from 572 field trials at 31 locations in the VCU Regions 1, 2, 3 and 4 in 2007-2011 were used. Each trial was run with and without the use of the Papadakis method. The Papadakis method improved the indices of experimental precision measures and reduced the number of experimental repetitions required to predict grain yield performance among the wheat genotypes. There were differences among the wheat adaptation regions in terms of the efficiency of the Papadakis method, the adjustment coefficient of the genotype averages and the increases in the selective accuracy of grain yield.

Season, sowing date, and row cover influences the production of cool season vegetables in movable high tunnels

2020 ◽  
Vol 100 (5) ◽  
pp. 528-536
Author(s):  
David A. Baumbauer ◽  
Macdonald H. Burgess
Keyword(s):  
Sowing Date ◽  
Fresh Weight ◽  
Cool Season ◽  
High Tunnel ◽  
Leafy Greens ◽  
Air Temperatures ◽  
Seeding Date ◽  
Northern Latitudes ◽  
Growing Degree Hours ◽  
High Tunnels

Moveable high tunnels offer the possibility of increasing the number of crops harvested from a given piece of ground in northern latitudes where there is a short growing season. In an effort to expand crop scheduling options, three leafy greens and three root vegetables were grown in the spring in a movable high tunnel, and in the fall were sown outside and the tunnel was moved over the crops in late September. The effects of seeding date and addition of row cover were further explored on fresh weight and days to harvest. Using row cover within the high tunnel increased growing degree hours (GDH) by an average of 29% in the spring and 17% in the fall over a high tunnel without row cover. Soil degree hours (SDH) in the high tunnel with row cover increased an average of 9% in the spring and 12% in the fall over the high tunnel without row cover. The addition of row cover increased yield of leafy greens and turnip by an average of 35% in spring 2018 when the outside air temperature was considerably below average. Early-seeded fall leafy greens out-yielded late-seeded by 52% due to the ability to make a second harvest. Using row cover within the high tunnel increased GDH and SDH during both spring and fall seasons and increased the yield of cool season vegetables when outside air temperatures were considerably below average.

Physiological and biophysical limits to work in the heat for clothed men and women

1978 ◽  
Vol 44 (6) ◽  
pp. 918-925 ◽  
Author(s):  
E. Kamon ◽  
B. Avellini ◽  
J. Krajewski
Keyword(s):  
Steady State ◽  
Vapor Pressure ◽  
Physiological Responses ◽  
Men And Women ◽  
Mean Values ◽  
Air Temperatures ◽  
Significant Difference ◽  
The Mean ◽  
Evaporative Heat Transfer ◽  
The One

Heat-acclimated, lightly clothed men and women (four of each) walked on a treadmill at 25% and 43% VO2 max, respectively, (M =194 W.m-2), under seven air temperatures (Ta) ranging from 36 to 52 degrees C. Each experiment involved 1 h of fixed and a 2nd h of progressively increasing ambient vapor pressure (Pa). The relative steady state of rectal temperature (Tre), mean skin temperature (Tsk), and heart rate (HR) reached in the 1st h were forced upward during the 2nd h by the rising Pa. The critical air vapor pressure (Pcrit) was identified by the Tre point of inflection for each Ta. One man did not fully reach steady state, but inflection could be determined for his physiological responses. The mean values of all points of inflection were calculated for Tre, Tsk, and HR. Significant sex difference in HR was found only by excluding the results of the one man. Tre and Tsk showed no significant difference between men and women. The coefficient for evaporative heat transfer (he), which could be derived using the Pcrit for the low Ta range, was 14.5 +/- 2.2 W.m-1 Torr-1.

scholarly journals Calcium nitrate and ammonium nitrate limestone as sources of nitrogen for oats and barley

1961 ◽  
Vol 33 (1) ◽  
pp. 159-168
Author(s):  
Pentti Hänninen ◽  
Armi Kaila
Keyword(s):  
Ammonium Nitrate ◽  
Nitrogen Content ◽  
Calcium Nitrate ◽  
Field Trials ◽  
The Other ◽  
Nitrogen Fertilizers ◽  
Malting Barley ◽  
Growing Period ◽  
Significant Difference ◽  
Cent Level

Calcium nitrate and ammonium nitrate limestone (»Oulunsalpietari») were compared as the nitrogen fertilizer for oats in 15 field trials and for barley in one trial. The trials were carried out in summers 1959 and 1960 in various places in Finland. The split plot technique was employed in order to reduce the variation as much as possible. In 1959 the amounts of nitrogen applied as these two fertilizers to the corresponding halves of the plots were 25 and 50 kg/ha. In 1960 also higher applications were used: 75 and 100 kg/ha of N. In three trials these fertilizers were compared both as a surface dressing and worked in. Visual observations suggested about 5—6 weeks after sowing a darker green colour in the stands treated with calcium nitrate as compared with the other half treated with ammonium nitrate limestone. These differences later disappeared. In some trials a higher nitrogen content of the plants from the calcium nitrate stands could be demonstrated during this period. The uptake of nitrogen by plants was regularly followed throughout the growing period. Owing to the large variation, usually, no statistically significant difference between the effect of the fertilizers could be detected. In a few cases the superiority of calcium nitrate could be demonstrated. No differences in the ripening could be found. In most trials there was a fairly regular tendency to higher yields and higher nitrogen content in the grain and straw produced by calcium nitrate. Yet, only in a few cases were the differences statistically significant at the five per cent level. Thus, it was concluded that on the basis of the results of these trials ammonium nitrate limestone and calcium nitrate may be considered practically equal as nitrogen fertilizers for oats. There was no difference in the yields of barley produced by these two fertilizers, but the nitrogen content of grains was significantly lower with ammonium nitrate limestone than with calcium nitrate. This may be worth further study in connection with the production of malting barley.

Mycotoxins in organically versus conventionally produced cereal grains and some other crops in temperate regions

2016 ◽  
Vol 9 (5) ◽  
pp. 755-770 ◽  
Author(s):  
G. Brodal ◽  
I.S. Hofgaard ◽  
G.S. Eriksen ◽  
A. Bernhoft ◽  
L. Sundheim
Keyword(s):  
Farming Systems ◽  
Weather Conditions ◽  
Field Trials ◽  
Cereal Grains ◽  
Organic System ◽  
Mycotoxin Contamination ◽  
Significant Difference ◽  
Apple Products ◽  
Low Levels ◽  
The Difference

This paper presents peer-reviewed studies comparing the content of deoxynivalenol (DON), HT-2+T-2 toxins, zearalenone (ZEA), nivalenol (NIV), ochratoxin A (OTA) and fumonisins in cereal grains, and patulin (PAT) in apple and apple-based products, produced in organically and conventionally grown crops in temperate regions. Some of the studies are based on data from controlled field trials, however, most are farm surveys and some are food basket surveys. Almost half of the studies focused on DON in cereals. The majority of these studies found no significant difference in DON content in grain from the two farming systems, but several studies showed lower DON content in organically than in conventionally produced cereals. A number of the investigations reported low DON levels in grain, far below the EU limits for food. Many authors suggested that weather conditions, years, locations, tillage practice and crop rotation are more important for the development of DON than the type of farming. Organically produced oats contained mainly lower levels of HT-2+T-2 toxins than conventionally produced oats. Most studies on ZEA reported no differences between farming systems, or lower concentrations in organically produced grain. For the other mycotoxins in cereals, mainly low levels and no differences between the two farming systems were reported. Some studies showed higher PAT contamination in organically than in conventionally produced apple and apple products. The difference may be due to more efficient disease control in conventional orchards. It cannot be concluded that any of the two farming systems increases the risk of mycotoxin contamination. Despite no use of fungicides, an organic system appears generally able to maintain mycotoxin contamination at low levels. More systematic comparisons from scientifically controlled field trials and surveys are needed to clarify if there are differences in the risk of mycotoxin contamination between organically and conventionally produced crops.

scholarly journals Performance and Profitability of Fungicides for Managing Soybean White Mold: A 10-Year Summary of Cooperative Trials

Plant Disease ◽  
2019 ◽  
Vol 103 (9) ◽  
pp. 2212-2220
Author(s):  
Jhonatan P. Barro ◽  
Maurício C. Meyer ◽  
Claúdia V. Godoy ◽  
Alfredo R. Dias ◽  
Carlos M. Utiamada ◽  
...  
Keyword(s):  
Low Cost ◽  
Disease Incidence ◽  
Network Models ◽  
Field Trials ◽  
White Mold ◽  
Yield Data ◽  
Soybean Price ◽  
Cost Treatment ◽  
Untreated Check ◽  
Yield Responses

White mold, caused by Sclerotinia sclerotiorum, is a yield-limiting disease of soybean in Brazil. Uniform fungicide trials have been conducted annually since 2009. Data from 74 cooperative field trials conducted over a 10-year period were assembled. We selected five fungicides applied two times around flowering: dimoxystrobin plus boscalid (DIMO+BOSC), carbendazim plus procymidone (CARB+PROC), fluazinam (FLUZ), fluopyram (FLUO), and procymidone (PROC). For comparison, thiophanate-methyl (TMET) applied four times was also included as a low-cost treatment. Network models were fitted to the log of white mold incidence (percentages) and log of sclerotia mass data (grams/hectare) and to the nontransformed yield data (kilograms/hectare) for each treatment, including the untreated check. Back-transformation of the meta-analytic estimates indicated that the lowest and highest mean (95% confidence interval [CI]) percent reductions in incidence and sclerotia mass were 54.2 (49.3 to 58.7) and 51.6% (43.7 to 58.3) for TMET and 83.8 (79.1 to 87.5) and 87% (81.9 to 91.6) for CARB+PROC, respectively. The overall mean (95% CI) yield responses ranged from 323 kg/ha (247.4 to 400.3) for TMET to 626 kg/ha (521.7 to 731.7) for DIMO+BOSC, but the variance was significantly reduced by a binary variable (30% threshold) describing disease incidence in the untreated check. On average, an increment of 352 kg/ha was estimated for trials where the incidence was >30% compared with the low-disease scenario. Hence, the probability of breaking even on fungicide costs for the high-disease scenario was >65% for the more effective, but more expensive fungicide (FLUZ) than TMET. For the low-disease scenario, profitability was less likely and depended more on variations in fungicide cost and soybean price.

scholarly journals Milk production and lactation length in Ankole cattle and Ankole crossbreds in Rwanda

2020 ◽  
Vol 52 (6) ◽  
pp. 2937-2943
Author(s):  
Maximillian Manzi ◽  
Lotta Rydhmer ◽  
Martin Ntawubizi ◽  
Claire D’Andre Hirwa ◽  
Callixte Karege ◽  
...  
Keyword(s):  
Milk Production ◽  
Milk Yield ◽  
Mixed Linear Model ◽  
Yield Data ◽  
Ankole Cattle ◽  
Lactation Length ◽  
Breed Group ◽  
Significant Difference ◽  
Daily Milk Yield ◽  
Daily Milk

Abstract This study assessed daily milk yield (DMY), 100-day (MY100), and 305-day (MY305) milk yield, and lactation length (LL) in purebred Ankole cattle and Ankole crossbreds, and the influence of environmental factors on these traits. Milk yield data were obtained for 865 cows and 1234 lactations and analyzed using a mixed linear model. The overall least squares mean of DMY, MY100, and MY305 across breed groups was 2.7 L (N = 1234, SD = 1.7), 262 L (N = 959, SD = 176), and 759 L (N = 448, SD = 439), respectively, while the average lactation length was 256 days (N = 960, SD = 122). All factors included (breed group, season and year of calving, and parity) were significant for yield traits, except season of calving for MY305. First-parity cows had the lowest milk production, and fourth-parity cows the highest. For all traits, pure Ankole cows had the lowest milk yield. Among the crossbreds, there was no significant difference between Ankole × Friesian, Ankole-Jersey mother × Sahiwal sire, and Ankole-Sahiwal mother × Jersey sire, or between Ankole × Sahiwal and Ankole-Sahiwal mother × Sahiwal sire. It was concluded that Ankole crosses with Friesian or Jersey can be beneficial, even under a management system of limited nutrition as in Rwanda.

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