Effectiveness of Bentazon Applied at Various Times of the Day

Weed Science ◽  
1976 ◽  
Vol 24 (6) ◽  
pp. 567-570 ◽  
Author(s):  
David L. Doran ◽  
Robert N. Andersen
Keyword(s):  
Glycine Max ◽  
Practical Importance ◽  
Field Studies ◽  
Early Morning ◽  
Time Of Day ◽  
Abutilon Theophrasti ◽  
Growth Chamber ◽  
Poor Control ◽  
Late Evening

Bentazon [3-isopropyl-1H-2,1,3-benzothiadiazin-(4) 3H-one 2, 2-dioxide] was applied postemergence to common cocklebur (Xanthium pensylvanicumWallr.) and velvetleaf (Abutilon theophrastiMedic.) at various times of the day in growth chamber and field studies and to soybeans [Glycine max(L.) Merr.] in field studies. Soybeans were tolerant of bentazon regardless of time of day when treated. Results with common cocklebur and velvetleaf suggest that the time of day when bentazon is applied can be of practical importance. Poor control might occur following application in late evening, night, or early morning.

Response of Velvetleaf(Abutilon theoprasti)to Bentazon as Affected by Leaf Orientation

Weed Science ◽  
1978 ◽  
Vol 26 (4) ◽  
pp. 393-395 ◽  
Author(s):  
R. N. Andersen ◽  
W. L. Koukkari
Keyword(s):  
Time Of Day ◽  
Abutilon Theophrasti ◽  
Growth Chamber ◽  
Leaf Orientation ◽  
Degree Of Control ◽  
Chamber Studies ◽  
Growth Chamber Studies

Greenhouse and growth chamber studies were conducted to determine the cause of previously observed differences in the effectiveness of bentazon [3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide] when applied at various times of the day to velvetleaf(Abutilon theophrastiMedic). Leaves of velvetleaf moved rhythmically from a near horizontal day position to a near vertical night position with the tip of the blade pointed downward. Plants were sprayed with bentazon at various times of day. The amount of spray retained and the degree of control decreased as the leaves moved toward the vertical downward night position. This suggested that a major cause of the time-of-day effect with bentazon treatments on velvetleaf is variation in the amount of spray intercepted and retained as a function of varying leaf angles.

Effects of Simulated Rainfall on Bentazon Activity

Weed Science ◽  
1975 ◽  
Vol 23 (2) ◽  
pp. 105-109 ◽  
Author(s):  
David L. Doran ◽  
Robert N. Andersen
Keyword(s):  
Glycine Max ◽  
Field Studies ◽  
Abutilon Theophrasti ◽  
Simulated Rainfall ◽  
Petroleum Oil ◽  
Spray Adjuvants

Simulated rainfall less than 8 hr after postemergence application of bentazon (3-isopropyl-1H-2,1,3-benzothiadiazin-(4)3H-one 2, 2-dioxide) reduced its activity on velvetleaf (Abutilon theophrastiMedic.) and common cocklebur (Xanthium pensylvanicumWallr.) in greenhouse studies. In field studies, simulated rainfall less than 24 hr after application reduced bentazon's activity on velvetleaf. on common cocklebur, bentazon's activity was reduced even if simulated rainfall was delayed for more than 24 hr after application. In greenhouse studies, spray adjuvants (vegetable or petroleum oil) were helpful in overcoming the detrimental effects of simulated rainfall. Greenhouse and field studies indicated that soybeans [Glycine max(L.) Merr.] could tolerate bentazon-oil adjuvant combinations.

The Preferences Scale: Multinational Assessment of a New Measure of Morningness

1993 ◽  
Vol 37 (13) ◽  
pp. 925-929 ◽  
Author(s):  
Carlla S. Smith ◽  
Simon Folkard ◽  
Robert A. Schmieder ◽  
Luis F. Parra ◽  
Evelien Spelten ◽  
...  
Keyword(s):  
Early Morning ◽  
Time Of Day ◽  
Self Report ◽  
Psychometric Assessment ◽  
Total N ◽  
Circadian Time ◽  
Validity Measures ◽  
Late Evening ◽  
Mean Differences ◽  
Biological Differences

Several self-report scales have been developed to measure morningness, or the preference for early morning or late evening activity (i.e., larks vs. owls). This individual difference in human circadian (time-of-day) rhythms has applications in the selection and placement of shiftworkers for night work in industry. Researchers have recently questioned the suitability of existing scales for people with alternate sleep-wake schedules and lifestyles. These factors may also render existing scales inappropriate for use in some cultures. To address this deficiency, we developed a new morningness scale (the preferences scale) that is not yoked to specific times of the 24-hour day and has a simplified response format. Data on the preferences scale were collected from university students (total N=1,212) in four countries (U.S., England, Holland, and Spain). Responses on external validity measures (self-rated alertness over the waking day and actual and preferred arise and bed times) and another morningness scale (for comparative purposes) were also collected. Although scale statistics (aggregate and by country) suggest that the psychometric properties of the preferences scale were adequate, scale mean differences existed across countries. These results may indicate cultural, as well as the established biological, differences in morningness. However, a more thorough psychometric assessment is needed to substantiate this possibility.

The Effect of Time of Day on the Activity of Postemergence Soybean Herbicides

2013 ◽  
Vol 27 (4) ◽  
pp. 690-695 ◽  
Author(s):  
Gregory J. Stopps ◽  
Robert E. Nurse ◽  
Peter H. Sikkema
Keyword(s):  
Weed Control ◽  
Yield Loss ◽  
Early Morning ◽  
Field Trials ◽  
Time Of Day ◽  
Weed Species ◽  
Time Of Application ◽  
Late Evening ◽  
Chlorimuron Ethyl ◽  
Herbicide Activity

The effect of time of day (TOD) on the activity of six common POST herbicides was investigated in field trials from 2007 to 2009 at two locations in southwestern Ontario. Percentage weed control was assessed following application of bentazon, chlorimuron-ethyl, fomesafen, glyphosate, imazethapyr, or quizalofop-p-ethyl applied at 3-h intervals from 6:00 A.M. to midnight, when weeds averaged 15 cm tall. The effect of time of day varied with weed species, but weed control was generally reduced when herbicides were applied at 6:00 A.M., 9:00 P.M., and midnight. Herbicide activity on velvetleaf was most frequently reduced, especially for chlorimuron-ethyl, glyphosate, and imazethapyr. Control of common ragweed with glyphosate and imazethapyr was also affected by the timing of application, and pigweed species only showed an effect with glyphosate. Variation in temperature, relative humidity, and dew presence/absence at different times of the day, as well as morphological/physiological characteristics such as weed size at time of application and diurnal leaf movement in response to light intensity, may account for the variation in weed control at different times of the day. Significant soybean yield loss was not observed in this study, but may occur if herbicide efficacy is severely reduced by application at inappropriate times of day. These results provide valuable information for growers, and suggest that POST herbicides are most effective when applied midday, rather than in the early morning or late evening.

scholarly journals Velvetleaf (Abutilon theophrasti) Recruitment, Survival, Seed Production, and Interference in Soybean (Glycine max)

Weed Science ◽  
1995 ◽  
Vol 43 (2) ◽  
pp. 226-232 ◽  
Author(s):  
John L. Lindquist ◽  
Bruce D. Maxwell ◽  
Douglas D. Buhler ◽  
Jeffrey L. Gunsolus
Keyword(s):  
Population Dynamics ◽  
Glycine Max ◽  
Seed Production ◽  
Seedling Survival ◽  
Field Studies ◽  
Abutilon Theophrasti ◽  
Soybean Yield ◽  
Demographic Processes ◽  
Crop Competition

Field studies were conducted at Rosemount, MN, in 1992 and 1993 to quantify the demographic processes regulating the population dynamics of velvetleaf in soybean as part of a corn-soybean rotation. A consistent 6.8 ± 0.5% of the total velvetleaf seedbank emerged each year. Less than 21% of all velvetleaf seedlings survived each year in mixture with soybean, due in part toVerticilliumspp wilt infection. The probability of seedling survival varied across time of emergence. Velvetleaf seed production in the absence of crop competition was 125 and 227 seeds plant−1in 1992 and 1993, respectively. Velvetleaf plants that emerged early produced greater numbers of seed than later emerging plants. Velvetleaf survival and seed production were reduced up to 82% in the presence of crop competition. Soybean yield varied across soybean densities in both years, but was not reduced across velvetleaf densities.

Application of linear splines to simulate daily changes in insolation

2020 ◽  
pp. 42-49
Author(s):  
Rudolf P. Trenkenshu ◽  
Alexander S. Lelekov ◽  
Anatoliy A. Chekushkin
Keyword(s):  
Linear Equations ◽  
Early Morning ◽  
Time Of Day ◽  
Linear Increase ◽  
Day Length ◽  
Maximum Height ◽  
Microalgae Culture ◽  
Late Evening ◽  
Linear Splines ◽  
Sunlight Intensity

The paper shows the possibility of using linear splines in modeling the daily change in solar radiation. The calculations were based on the generally accepted cosine expression used for modeling insolation changes on the surface of lakes and the ocean. The equation parameters are set for the conditions of Sevastopol (44°35'N, 33°30' E): the maximum height of the sun above the horizon is about 68 degrees, the day length is 15 hours. The model curve was divided into three sections. For the early morning hours and late evening, the sunlight intensity is low and is below the “compensation point” of photosynthesis. So these areas were not considered during modeling. Three sites: the increase in irradiation from 6 to 12 hours, the maximum irradiation from 12 to 14 hours, and the decrease in irradiation from 14 to 20 hours are described by linear equations. It is shown that the deviations in the description of the data of the dependence of the sunlight intensity on the time of day by linear splines from the generally accepted formula in the form of a cosine do not exceed 5%. An example of experimental data of linear growth of productivity of A. platensis culture is given. Based on the assumption that the growth rate of microalgae culture is proportional to the amount of energy absorbed, the linear increase in productivity can be explained by a linear increase in the intensity of sunlight.

Thermoregulatory responses to cold water at different times of day

1999 ◽  
Vol 87 (1) ◽  
pp. 243-246 ◽  
Author(s):  
John W. Castellani ◽  
Andrew J. Young ◽  
James E. Kain ◽  
Michael N. Sawka
Keyword(s):  
Cold Water ◽  
Water Immersion ◽  
Early Morning ◽  
Cold Water Immersion ◽  
Time Of Day ◽  
Mean Skin Temperature ◽  
Mean Body Temperature ◽  
Metabolic Heat ◽  
Body Temperature Change ◽  
The Mean

This study examined how time of day affects thermoregulation during cold-water immersion (CWI). It was hypothesized that the shivering and vasoconstrictor responses to CWI would differ at 0700 vs. 1500 because of lower initial core temperatures (Tcore) at 0700. Nine men were immersed (20°C, 2 h) at 0700 and 1500 on 2 days. No differences ( P > 0.05) between times were observed for metabolic heat production (M˙, 150 W ⋅ m−2), heat flow (250 W ⋅ m−2), mean skin temperature (T sk, 21°C), and the mean body temperature-change in M˙(ΔM˙) relationship. Rectal temperature (Tre) was higher ( P < 0.05) before (Δ = 0.4°C) and throughout CWI during 1500. The change in Tre was greater ( P < 0.05) at 1500 (−1.4°C) vs. 0700 (−1.2°C), likely because of the higher Tre-T skgradient (0.3°C) at 1500. These data indicate that shivering and vasoconstriction are not affected by time of day. These observations raise the possibility that CWI may increase the risk of hypothermia in the early morning because of a lower initial Tcore.

296 Sex differences in sleep and wakefulness of police officers working shifts: evidence from a field study

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A118-A118
Author(s):  
Gabriela Caetano ◽  
Laura Kervezee ◽  
Fernando Gonzales-Aste ◽  
Philippe Boudreau ◽  
Diane Boivin
Keyword(s):  
Sex Differences ◽  
Circadian Rhythms ◽  
Shift Work ◽  
Police Officers ◽  
Field Studies ◽  
Time Of Day ◽  
Cycle Phase ◽  
Shift Workers ◽  
Work Related ◽  
Time Awake

Abstract Introduction National reports of work-related injuries found the excess risk of work injury attributed to shift work to be significantly higher among women. The Working Time Society (WTS) concluded that male sex is one of the few factors that is “consistently associated with perceived or actual shift work tolerance”. However, it is unclear if physiological parameters are involved. Laboratory-controlled studies report sex differences in circadian rhythms (body temperature, melatonin). In sleep deprivation protocols, alertness and cognitive performances were affected by sex, menstrual cycle phase and hormonal contraceptives [HC] use. Nevertheless, field studies that compare male and female shift workers are scarce. Methods An observational study including 76 police officers working on patrol: 56 males and 20 females (11 using [HC], 6 not using [non-HC] and 3 with unknown use of hormonal contraception) aged 32.0 ± 5.3 years. Participants were followed throughout a month-long work cycle (1,457 morning, evening, night, or other shifts, plus rest days). They filled out time-stamped questionnaires (Samn-Perelli, KSS, Visual Analogue Scales, ~5/day; sleep and work-related information, ~1–2/day), completed 5-min Psychomotor Vigilance Tasks (PVT, ~2/day), and wore an actigraph to collect activity data. Linear mixed-effects models were used to analyze the effects of group, time awake and time-of-day on fatigue, sleepiness, alertness, mood and PVT measures. Results Self-reported measures and psychomotor performance significantly varied with time awake and time-of-day. Fatigue and sleepiness levels were significantly higher among female compared to male police officers, both with time awake and across the 24-h day. These variations were similar between non-HC females and the other groups. Compared to males, HC females were more fatigued and less alert, both with time awake and across the 24-h day, and sleepier with time awake. Having children at home did not explain these differences. Conclusion The results of this study expand our knowledge on the sex differences in the sleep and circadian physiology and demonstrate a critical effect of HC on women fatigue, sleepiness and alertness when working shifts. Sex and hormonal parameters must be considered in occupational medicine as well as in future laboratory and field studies on shift workers and circadian rhythms. Support (if any) IRSST, FRQS.

Weed Control with Reduced Rates of Chlorimuron Plus Metribuzin and Imazethapyr in No-Till Narrow-Row Soybean (Glycine max)

1998 ◽  
Vol 12 (1) ◽  
pp. 32-36 ◽  
Author(s):  
William G. Johnson ◽  
Jeffrey S. Dilbeck ◽  
Michael S. Defelice ◽  
J. Andrew Kendig
Keyword(s):  
Glycine Max ◽  
Weed Control ◽  
Field Studies ◽  
Weed Suppression ◽  
Crop Response ◽  
Soybean Production ◽  
No Till ◽  
Giant Foxtail ◽  
The Difference ◽  
Narrow Row

Field studies were conducted at three locations in 1993 and 1994 to evaluate weed control and crop response to combinations of glyphosate, metolachlor, 0.5 X and 1 X label rates of chlorimuron plus metribuzin applied prior to planting (PP), and 0.5 X and 1 X label rates of imazethapyr applied early postemergence (EPOST) or postemergence (POST) in no-till narrow-row soybean production. Giant foxtail densities were reduced with sequential PP followed by (fb) EPOST or POST treatments. Large crabgrass was reduced equivalently with all herbicide combinations involving chlorimuron plus metribuzin PP fb imazethapyr. Common cocklebur control was variable but was usually greater with treatments that included imazethapyr. Ivyleaf morningglory densities were not reduced with any herbicide combinations. Sequential PP fb EPOST or POST treatments tended to provide slightly better weed suppression than PP-only treatments, but the difference was rarely significant. Soybean yields with treatments utilizing 0.5 X rates were usually equal to 1 X rates.

scholarly journals PHOSPHORUS NUTRITION OF SOYBEANS AS AFFECTED BY PLACEMENT OF FERTILIZER PHOSPHORUS

1983 ◽  
Vol 63 (2) ◽  
pp. 199-210 ◽  
Author(s):  
C. W. BULLEN ◽  
R. J. SOPER ◽  
L. D. BAILEY
Keyword(s):  
Glycine Max ◽  
Total Phosphorus ◽  
Dry Matter ◽  
Field Experiments ◽  
Seedling Emergence ◽  
Phosphorus Uptake ◽  
Growth Chamber ◽  
Grain Yields ◽  
Chamber Experiment ◽  
Glycine Max L

Growth chamber and field experiments were conducted on Southern Manitoba soils, low in available soil phosphorus, to investigate the effects of various placement methods and levels of phosphorus fertilizer on soybean (Glycine max (L.) Merrill ’Maple Presto’). It was found that soybean responded well to applied phosphorus on low-P soil in growth chamber studies. In the first growth chamber experiment, P was applied in solution to 100%, 50%, 25%, 12.5% and 1% of the total soil volume. Dry matter yields, total phosphorus uptake and utilization of fertilizer P increased at each level of applied P as the size of the phosphated band was decreased. The results were partly attributed to greater chemical availability of P in the smaller zones of P fertilizer reaction. In a second growth chamber experiment, soybeans responded differently to phosphorus banded in six different locations. Placement of the fertilizer 2.5 cm directly below the seed was more effective in increasing dry matter yield, total phosphorus uptake and fertilizer P utilization than placement 2.5 cm and 5 cm away at the same depth or placement 5 cm below the seed, whether the band was directly below, 2.5 cm away or 5 cm away. Soybean yield responses in the field were greatest with P banded 2.5 cm directly below the seed on low-P soils. Placement of P 2.5 cm below the seed resulted in grain yields that were 64% and 50% higher (at the two sites) than those obtained in control plots. Sidebanding P, 2.5 cm below and 2.5 cm away from the seed at the same level of application, improved grain yields of control plots by 40% and 39%. Seed placement and broadcast applications of P were not as effective in increasing grain yields. Broadcasting P in fall or in spring at rates of up to 52.38 kg P/ha did not result in significantly higher grain yields than those obtained in control plots. Placement of P in contact with the seed appeared to reduce seedling emergence, resulting in depressed yields when 52.38 kg P/ha were applied. Key words: Glycine max L. Merrill, ’Maple Presto’

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