ENVIRONMENTAL CONDITIONS WITHIN A NORTHERN ONTARIO MINE CONVERTED FOR VEGETABLE PRODUCTION

1982 ◽  
Vol 62 (1) ◽  
pp. 203-210
Author(s):  
M. D. SERBANESCU ◽  
J. D. SHORTHOUSE ◽  
T. H. PETERS
Keyword(s):  
High Pressure ◽  
Relative Humidity ◽  
Plant Growth ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Mercury Vapor ◽  
Adiabatic Compression ◽  
Vegetable Production ◽  
Geothermal Heat ◽  
Northern Ontario

Conditions available for growing vegetables within operating drifts (tunnels) at various levels of the Creighton Mine Number 9 shaft of INCO Metals Company near Sudbury, Ontario are reported. Heat due to adiabatic compression and geothermal heat within drifts 1706.9 m (5600 ft) underground provided an air temperature of 23–29 °C and 15–18 °C at 1219.2 m (4000 ft). Relative humidity, CO2, air quality, and air flow were satisfactory for plant growth. Light was provided by high intensity discharge lamps (metal halide, high pressure sodium, and mercury vapor). Preliminary results indicated that environmental conditions in the drifts were adequate for growth of certain plants.

Influence of Environmental-Conditions on Flight Duration of Epiphyas-Postvittana (Walker) (Lepidoptera, Tortricidae)

1992 ◽  
Vol 40 (5) ◽  
pp. 477 ◽  
Author(s):  
W Danthanarayana ◽  
H Gu
Keyword(s):  
Body Weight ◽  
Relative Humidity ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Epiphyas Postvittana ◽  
Atmospheric Humidity ◽  
Flight Duration ◽  
Reduced Body ◽  
Light Brown Apple Moth ◽  
Honey Solution

Flight responses of the light brown apple moth, Epiphyas postvittana (Walker), to changes in air temperature, atmospheric humidity, feeding and mating activities were studied under controlled conditions. Flights occurred within the air temperature range from 10 to 30-degrees-C, with the longest flight duration at 20-degrees-C for both sexes. A change of atmospheric humidity significantly influenced flight duration of females, but not of males, at 20-degrees-C. The longest flight duration of the female moths occurred at a relative humidity of 60%. Provision of honey solution or water improved flight duration of the moths aged three days or older. Mating increased flight duration of females from the age of three days onwards, presumably as a result of reduced body weight associated with oviposition.

scholarly journals Evaluation of Microbial and Conventional Insecticides for Control of Larval European Corn Borer on Whorl Stage Corn, Clay Center, Ne, 1995

1996 ◽  
Vol 21 (1) ◽  
pp. 218-218
Author(s):  
Terry A. DeVries ◽  
Robert J. Wright
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Wind Direction ◽  
Growth Stage ◽  
Crop Growth ◽  
Larval Feeding ◽  
Egg Masses ◽  
Crop Growth Stage ◽  
Over The Top

Abstract Bacillus thuringiensis formulations and conventional insecticides were evaluated for efficacy against larval ECB in whorl stage field corn. All plots were planted without soil insecticide on 16 May. The experimental design was a RCB with 4 replicates. Each plot consisted of a single row, 40 ft long with a 30-inch row spacing. Plots were artificially infested with black-head stage ECB egg masses. The egg masses were deposited on wax paper discs, precounted in the laboratory and placed in the whorl of the infested plants on 30 Jun and 9 Jul. Crop growth stage was 37 and 57 inches extended leaf height, respectively. The same 5 plants in each treatment replicate were infested with 10 egg masses per infestation date. All granular insecticides were applied on 13 Jul. Environmental conditions were: air temperature, 81°F; wind direction and speed, west (250°) at 7 mph; relative humidity, 53%; and crop growth stage, 63 inches extended leaf height. A 10-inch Almaco smooth belt cone rear mounted on a Hahn Hi-Boy was used to apply preweighed amounts of the granular insecticides over the top of the plant whorls (G). Liquid insecticides were applied on 15 Jul. Environmental conditions were: air temperature, 74°F; wind direction and speed, east (80°) at 5 mph; relative humidity, 76%; and crop growth stage, 67 inches extended leaf height. A CO2 pressurized backpack sprayer at 30 psi was used to apply a band application over the top of the whorl (total spray volume = 1050 ml/plot) of premeasured amounts of the liquid insecticides (L). All infested plants were evaluated for ECB larval feeding damage on 14-15 Aug. The stalks of the infested plants were split lengthwise and the accumulated length and number of cavities in the 5 plants per treatment replicate were used to evaluate ECB larval damage. The percent infestation at evaluation was determined by the plants with a minimum of 1 cavity per treatment replicate. Data were analyzed by ANOVA for RCB with mean separation using DMRT.

scholarly journals Production and Germination of Conidia of Trichoderma stromaticum, a Mycoparasite of Crinipellis perniciosa on Cacao

2002 ◽  
Vol 92 (10) ◽  
pp. 1032-1037 ◽  
Author(s):  
S. Sanogo ◽  
A. Pomella ◽  
P. K. Hebbar ◽  
B. Bailey ◽  
J. C. B. Costa ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Growth Characteristics ◽  
Fruiting Bodies ◽  
High Moisture ◽  
Crinipellis Perniciosa ◽  
Broom Disease ◽  
Moisture Conditions ◽  
Incubation Temperatures

Growth characteristics of the fungus Trichoderma stromaticum, a mycoparasite on the mycelium and fruiting bodies of Crinipellis perniciosa, the causal agent of witches'-broom disease of cacao, were evaluated under controlled environmental conditions. The ability of T. stromaticum to produce conidia and germinate on dry brooms was evaluated at three constant temperatures (20, 25, and 30°C) and two constant relative humidities (75 and 100%). T. stromaticum produced abundant conidia on brooms at 100% relative humidity and incubation temperatures of 20 and 25°C, but none at 30°C. Sporulation of T. stromaticum was not observed at 75% relative humidity at any temperature. At 100% relative humidity and either at 20 or 25°C, treatment of brooms with T. stromaticum suppressed C. perniciosa within 7 days. In contrast, at 30°C, treatment with T. stromaticum had no effect on the pathogen in brooms maintained at either 75 or 100% relative humidity. Mycelium of C. perniciosa grew from brooms at all temperatures at 100% relative humidity. Conidial germination on broom tissue approximated 80% at temperatures from 20 to 30°C. Results suggest that applying T. stromaticum under high-moisture conditions when the air temperature is below 30°C may enhance the establishment of this mycoparasite in cacao plantations.

scholarly journals Variation of Frost Roughness on a Flat Plate Under Forced Convection

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Tongxin Zhang ◽  
Dennis L. O’Neal ◽  
Stephen T. McClain
Keyword(s):  
Relative Humidity ◽  
Surface Temperature ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Mean Square ◽  
Empirical Correlations ◽  
Testing Conditions ◽  
Air Temperatures ◽  
Photogrammetric Method ◽  
Grain Roughness

Abstract Experiments were conducted on a cold flat aluminum plate to characterize the variation of frost roughness over both time and location on the surfaces. The testing conditions included air temperatures from 8 to 16 °C, wall temperatures from −20 to −10 °C, relative humidities from 60 to 80%, and air velocities from 0.5 to 2.5 m/s. Each test lasted 2 h. A 3D photogrammetric method was employed to measure the variation in frost root-mean-square height and skewness by location and time. These data were used to develop the equivalent sand-grain roughness for the frost at different locations and time. The experimental results showed that frost roughness varied by location and changed with time. For the environmental conditions in this study, relative humidity and air temperature were the most important factors determining changes in the peak frost roughness. For example, at an air temperature of 12 °C and a surface temperature of −15 °C, the frost roughness peaked at about 40 min for a relative humidity of 80% and 90 min for a relative humidity of 60%. Empirical correlations were provided to describe the relationships between the environmental conditions and the appearance of the peak frost roughness.

scholarly journals Microclimate Condition in the Natural Ventilated Greenhouse

2020 ◽  
Vol 44 (1) ◽  
pp. 31
Author(s):  
Vita Ayu Kusuma Dewi ◽  
Budi Indra Setiawan ◽  
Roh Santoso Budi Waspodo ◽  
Liyantono Liyantono
Keyword(s):  
Relative Humidity ◽  
Solar Radiation ◽  
Plant Growth ◽  
Air Temperature ◽  
Environmental Engineering ◽  
Primary Data ◽  
Climate Factors ◽  
Second Stage ◽  
Two Stages ◽  
Determining Factor

A Greenhouse has a different microclimate compared to the outside field. Climate parameters such as solar radiation and air temperature are important parameters that affect plant growth and productivity. This research aims to understand the relation of climate factors in the inside and outside Greenhouse, the effect of microclimate on evapotranspiration and to predict the amount og evapotranspiration inside the Greenhouse. Microclimate analysis was held in two stages, the firststage was from February 5 to March 21, 2018 and the second stage from March 19 to April 29, 2019 at the Department of Civil and Environmental Engineering, IPB University. Primary data was measured by the Decagon sensor. Solar radiation was collected using the Decagon PYR Pyranometer sensor and air temperature using the Decagon VP-4 sensor. Based on the result, the daily air temperature inside the Greenhouse was higher than that of the outside. The inside solar radiation was lower than that of outside the Greenhouse. The relative humidity fluctuated, and the air pressure was higher inside the Greenhouse. Evapotranspiration inside the Greenhouse was lower than outside and solar radiation was the most determining factor of evapotranspiration.

Factors Affecting the Translocation of14C-Mefluidide in Soybeans(Glycine max), Common Cocklebur(Xanthium pensylvanicum), and Johnsongrass(Sorghum halepense)

Weed Science ◽  
1978 ◽  
Vol 26 (4) ◽  
pp. 382-388 ◽  
Author(s):  
C. G. McWhorter ◽  
G. D. Wills
Keyword(s):  
Glycine Max ◽  
Relative Humidity ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Fold Increase ◽  
Constant Level ◽  
Sorghum Halepense ◽  
Factors Affecting ◽  
Treated Area ◽  
Lower Stem

Absorption and translocation of14C-mefluidide {N-[2,4-dimethyl-5-[[(trifluoromethyl)sulfonyl] amino] phenyl] acetamide} in soybeans [Glycine max(L.) Merr. ‘Lee 68’], common cocklebur(Xanthium pensylvanicumWallr.), and johnsongrass [Sorghum halepense(L.) Pers.] were evaluated under different environmental conditions with and without adjuvants. At a constant level of 40 or 100% relative humidity (RH), an increase in air temperature from 22 to 32 C resulted in a two- to three-fold increase in absorption and a four- to eight-fold increase in translocation of the14C in soybeans following application to the second trifoliolate. At constant 22 or 32 C an increase from 40 to 100% RH resulted in less than a two-fold increase in absorption or translocation of14C in soybeans. Autoradiograms indicated that movement of the14C was primarily into leaves above the treated area. Translocation of14C was significantly greater following application to the lower stem than to leaves. In common cocklebur,14C absorption increased about three-fold at both 22 and 32 C with an increase from 40 to 100% RH following application to the second alternate leaf. At both levels of RH, absorption and translocation increased as the temperature was increased from 22 to 32 C. The addition of an adjuvant increased absorption and translocation in common cocklebur under all environmental conditions. When14C-mefluidide was applied without an adjuvant to johnsongrass, absorption increased five- to six-fold at both 22 and 32 C as RH was increased from 40 to 100%. Translocation in johnsongrass was often affected less by variations in temperature than it was in soybeans or common cocklebur. The adjuvant increased absorption and translocation of the14C-label of mefluidide in johnsongrass. The14C-label accumulated primarily in the distal leaf of johnsongrass or in leaves above the treated area.

Effects of Adjuvants and Environment on the Toxicity of Dalapon to Johnsongrass

Weed Science ◽  
1976 ◽  
Vol 24 (3) ◽  
pp. 257-260 ◽  
Author(s):  
C. G. Mcwhorter ◽  
T. N. Jordan
Keyword(s):  
Soil Moisture ◽  
Relative Humidity ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Sorghum Halepense

Johnsongrass [Sorghum halepense(L.) Pers.] regrowth was used as an index for penetration and translocation of dalapon (2,2-dichloropropionic acid) with and without adjuvants under different environmental conditions. Johnsongrass control with dalapon at 1.12 kg/ha without surfactant decreased as air temperature increased from 16 to 27 to 38 C. Plants at 16 and 27 C with 100% relative humidity (RH) were more susceptible to dalapon without surfactant than were plants at 35% RH. The presence of 1% surfactant in dalapon solutions increased johnsongrass control above that of dalapon alone at 27 and 38 C regardless of RH. Adding 1% surfactant and maintaining plants at 100% RH and 38 C resulted in significantly less johnsongrass control than that at 35% RH and 38 C. The addition of 0.1 M KH2PO4to mixtures of dalapon + surfactant restored effectiveness at 100% RH and 38 C. Dalapon applied without surfactant was more injurious to johnsongrass grown with 40% soil moisture than with 25% soil moisture regardless of air temperature or RH. When plants were maintained at 27 or 38 C with 25% soil moisture, 0.1 M KH2PO4+ surfactant was more beneficial than surfactant alone in increasing dalapon toxicity to johnsongrass. At 40% soil moisture, johnsongrass control with dalapon + 1 % surfactant was not improved with the addition of KH2PO4regardless of air temperature.

scholarly journals (297) Continuous Fogging using a Nozzle with an Upward Air Stream Contributes to Steady Air Temperature during Greenhouse Cooling

HortScience ◽  
2005 ◽  
Vol 40 (4) ◽  
pp. 1009D-1009
Author(s):  
Hiromi Toida ◽  
Toyoki Kozai ◽  
Katsumi Ohyama ◽  
Keyword(s):  
High Risk ◽  
Relative Humidity ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Cooling Efficiency ◽  
Air Stream ◽  
Evaporation Ratio ◽  
Plant Foliage ◽  
Indoor Conditions

Fogging systems are still not widely used for greenhouse cooling, primarily due to their low fog: evaporation ratio, resulting in a low cooling efficiency and a high risk of pathogen expansion caused by excess wetness of plant foliage. The fogging is operated intermittently because of these problems. Consequently, the air temperature and relative humidity fluctuates inside the greenhouse. If nozzles with a high fog: evaporation ratio are employed, the fogging can be operated continuously. By continuous fogging, steady air temperature and relative humidity can be achieved inside the greenhouse. In our previous study under indoor conditions, a high fog: evaporation ratio was achieved by installing two small fans close to a conventional upright nozzle in order to obtain an upward air stream. The objective of this study was to draw a comparison between the environmental conditions inside a greenhouse with the continuous fogging with small fans and that with the conventional intermittent fogging without fans. Reduced fluctuation of the air temperature and relative humidity inside the greenhouse were observed in the case of continuous fogging as compared with that observed in the case of intermittent fogging. The air temperature inside the greenhouse during cooling was lower than that before cooling in both methods. In the case of continuous fogging, the adjustment of the amount of fogged water will provide the desired environmental conditions inside the greenhouse.

Translocation of14C-Glyphosate in Soybeans (Glycine max) and Johnsongrass (Sorghum halepense)

Weed Science ◽  
1980 ◽  
Vol 28 (1) ◽  
pp. 113-118 ◽  
Author(s):  
C. G. McWhorter ◽  
T. N. Jordan ◽  
G. D. Wills
Keyword(s):  
Soil Moisture ◽  
Glycine Max ◽  
Relative Humidity ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Moisture Absorption ◽  
Field Capacity ◽  
Sorghum Halepense ◽  
Total Absorption ◽  
Wilting Point

Absorption and translocation of14C-glyphosate [N-(phosphonomethyl)glycine] in johnsongrass [Sorghum halepense(L.) Pers.] and soybeans [Glycine max(L.) Merr. ‘Lee 68’] were evaluated under various environmental conditions. The toxicity of unlabeled glyphosate applied similarly was determined in soybeans under similar conditions. In johnsongrass, absorption of14C-glyphosate nearly doubled and translocation increased as air temperature increased from 24 to 35 C. Translocation in johnsongrass and soybeans was often greater at a relative humidity (RH) of 100% than at 45% and at a soil moisture level of 20% (field capacity) than at 12% (near the wilting point). In soybeans, absorption of14C-glyphosate increased about 100%, translocation increased between 100 and 1200%, and glyphosate toxicity increased more than 200% as temperature decreased from 35 to 24 C. At 35 C, translocation in soybeans was often greater at 20% than 12% soil moisture. Absorption of14C-glyphosate in soybeans was greater when the herbicide was applied to mature rather than immature leaves and stems, but the age of the treated tissue had less effect on14C translocation. The addition of surfactant plus KH2PO4to the treatment solution increased glyphosate absorption and translocation in soybeans, but addition of surfactant alone reduced translocation and addition of KH2PO4alone increased translocation. Injury to six soybean cultivars from application of unlabeled glyphosate at 0.4 kg/ha ranged from 37% to 95% while total absorption of14C-glyphosate into treated leaves of the same six cultivars ranged from 23% to 74% of the amount applied.

scholarly journals Influence of different protected cultivation structures on performance of cucumber (Cucumis sativus L.) in Indian hot arid region

2021 ◽  
Vol 23 (3) ◽  
pp. 265-271
Author(s):  
P.S. KHAPTE ◽  
H.M. MEENA ◽  
PRADEEP KUMAR ◽  
UDAY BURMAN ◽  
ANURAG SAXENA ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Plant Growth ◽  
Air Temperature ◽  
Arid Region ◽  
Arid Regions ◽  
Physiological Activity ◽  
Cucumis Sativus L ◽  
Active Radiation ◽  
Protected Cultivation ◽  
Greenhouse Cucumber

The performance of gynoecious cucumber (cv. Terminator) was evaluated under three protected structures viz., naturally ventilated polyhouse (NVP), insect proof net house (INH) and shade net house (SNH) at Jodhpur, Rajasthan in hot arid region of India. The photosynthetically active radiation (PAR) inside these structures during cropping period ranged from 154-842 μmol m-2 s-1 which was much lower than the outside. Among structures, air temperature was 1.2°C and 0.7°C lower while relative humidity (RH) was 17 and 4 per cent higher in NVP and SNH respectively as compared to INH. Relatively low air as well as soil temperature, coupled with high RH and optimal radiation in NVP led to better plant growth and physiological activity which resulted in 42 and 142per cent higher yield than INH and SNH, respectively. Hence, it can be recommended that NVP is the best low-tech protected structure which modifies the microclimate favouring successful cultivation of greenhouse cucumber in Indian hot arid regions.

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