scholarly journals Probability of Low Temperature Stress at Different Growth Stages of Boro Rice

2016 ◽  
Vol 19 (2) ◽  
pp. 19-27 ◽  
Author(s):  
MS Kabir ◽  
M Howlader ◽  
JK Biswas ◽  
MAA Mahbub ◽  
M Nur E Elahi
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Short Duration ◽  
Rice Crop ◽  
Growth And Yield ◽  
Maximum Temperature ◽  
Growth Stages ◽  
Growth Duration ◽  
Long Duration ◽  
Boro Rice

CORRECTION: Due to a number of formatting and layout issues, the PDF of this paper was replaced on 10th October 2016.The most sensitive stages of Boro rice against the low temperature are agronomic panicle initiation (API), reduction division (RD) and flowering/anthesis. The critical low temperature is growth stage specific. The time and intensity of the critical low temperature during Boro season has a direct impact on the growth and yield of a crop. Therefore, it is necessary to understand the probability of the critical low temperature with respect to the growth stages to have a good planning for safe harvest. Long term weekly low temperature data have been used to estimate the probability of falling low temperature on those stages and the return period was computed. The growth durations of 1- and 30- November seeded Boro rice crop from 45-day-old seedling of BRRI dhan28 (short duration) and BRRI dhan29 (long duration) are considered to observe the probability. A Boro crop encountering critical low temperature is appeared to suffer from cool injury. The extent of cool injury depends on the nature and duration of low temperature and diurnal change of low (night) and high (day) temperature. The critical low temperature for a rice crop at API, RD and anthesis are 18, 19 and 22°C, respectively. Boro rice is grown between November and May. The low temperature occurs from October to early March. There is, therefore, the probability of low temperature occurrence from the crop establishment to the flowering stage is a great concern. The probability of experiencing stage-wise critical temperature approaches to 100% for early established and short duration crop. However, the late established and long duration crop has the probability little less than the early and short duration crop. In a study it has been observed that short duration BRRI dhan28 having 64.6% sterility to yield 2.5 t ha-1 and BRRI dhan29, 40.8% sterility to yield 6.5 t ha-1. The percentages of corresponding sterility for late established crops were 35.9 and 32.8%. Irrespective of growth duration, the yield is affected a little of the late established crop. Despite low temperature along with the reproductive phase, the late established crop is quite safe due to the parallel high (day) temperature (31-35°C). The high maximum temperature appears to play an important role through the alleviating effect of low temperature. But for early-established particularly short duration variety could not escape the low temperature at some of its sensitive growth stages as the high temperature appears to stay a several degree low (27-29°C) at that time. The low level of high temperature is appeared to drag down the low temperature to aggravate the growth and development of a crop. Therefore, not only the variation of high temperature of the day but also the variation of critical low temperature might have some role in alleviating effect of cool-injury. The periodic return of critical low temperature (10-15°C) during the reproductive stage may occur every year or every alternate year depending on the time across the cropping season and the region as well. Therefore, the critical low temperature, the high temperature during the low temperature period, periodic return of the critical low temperature with respect to growing region and concerned factors should be a consideration for planning a Boro crop.Bangladesh Rice j. 2015, 19(2): 19-27

Effect of sowing time and nitrogen on rice cultivars of differing growth duration in New South Wales 2. Biomass production and partitioning

1994 ◽  
Vol 34 (7) ◽  
pp. 939
Author(s):  
RF Reinke ◽  
LG Lewin ◽  
RL Williams
Keyword(s):  
Low Temperature ◽  
Short Duration ◽  
New South ◽  
New South Wales ◽  
Biomass Accumulation ◽  
Rice Cultivars ◽  
Growth Duration ◽  
Sowing Time ◽  
South Wales ◽  
Long Duration

In New South Wales, rice cultivars with shorter growth duration are sought to reduce water use and to increase the efficiency of rice production. We examined the biomass accumulation of a short-duration cultivar in comparison with 3 long-duration cultivars across a range of sowing time and nitrogen treatments. The biomass accumulation of the short-duration cultivar was smaller than that of the long-duration cultivars, but the yield potential was similar. This was achieved by the production of similar number of florets per m2, despite smaller biomass at flowering, and greater harvest index. Only early-sown treatments resulted in smaller yield of the short-duration cultivar due to restricted biomass accumulation and floret production. A simple biological model of post-anthesis growth, which included the effect of low temperature, predicted growth with an accuracy similar to that of the measurements. The low temperature function assumed growth stopped following a daily minimum temperature below a specified threshold, and the number of days without growth was a function of the severity of the temperature. We concluded that the yield of short-duration cultivars may be less stable when stress occurs during grain filling because there is less biomass at anthesis and, therefore, less reserve available to fill the grain.

Environment and Bromoxynil Phytotoxicity

Weed Science ◽  
1986 ◽  
Vol 34 (1) ◽  
pp. 101-105 ◽  
Author(s):  
John D. Nalewaja ◽  
Grzegorz Skrzypczak
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Low Temperatures ◽  
Practical Importance ◽  
Amaranthus Retroflexus ◽  
Controlled Environment ◽  
Growth Stages ◽  
Redroot Pigweed ◽  
Wild Mustard ◽  
Simulated Rain

Experiments in controlled-environment chambers indicated that high temperature, 30 C, increased the phytotoxicity of bromoxynil (3,5-dibromo-4-hydroxybenzonitrile) to wild mustard (Sinapis arvensisL. # SINAR) and redroot pigweed (Amaranthus retroflexusL. # AMARE) compared to low temperature, 10 C, during and after treatment. Bromoxynil phytotoxicity generally was higher at relative humidities of 90 to 95% compared to 40 to 60%, but relative humidity had less influence on bromoxynil phytotoxicity than did temperature. A simulated rain immediately after bromoxynil treatment reduced control of both species, but the reduction was of no practical importance for wild mustard. The data indicate that wild mustard and redroot pigweed control would be reduced by bromoxynil application during a period of low temperatures or to plants in advanced growth stages.

Effect of sowing time and nitrogen on rice cultivars of differing growth duration in New South Wales. 1. Yield and yield components

1994 ◽  
Vol 34 (7) ◽  
pp. 933 ◽  
Author(s):  
RF Reinke ◽  
LG Lewin ◽  
RL Williams
Keyword(s):  
Short Duration ◽  
New South ◽  
New South Wales ◽  
Yield Potential ◽  
High Yield ◽  
Yield Response ◽  
Growth Duration ◽  
Sowing Time ◽  
South Wales ◽  
Long Duration

New South Wales rice crops commonly take >180 days from sowing to harvest, and a reduction in crop duration is sought to increase the efficiency of rice production. The response of rice cultivars of differing growth duration to sowing time and N application was examined across 2 growing seasons. The highest yields were obtained at early sowing dates in each season. In season 2, the maximum yield of the short-duration cultivar M101 was not significantly different to the long-duration cultivars Calrose, Pelde, and M7, with yields >12 t/ha. However, yield of cv. M101 was significantly less than the long-duration cultivars at an early sowing date in season 1. Analysis of yield components did not clearly indicate the reason for reduced yield of the short duration cultivar. Damage by birds and mice before harvest, exacerbated by early maturity, is a possible cause.Later sowing reduced yields of all cultivars, with the short-duration cultivar-least affected. Optimum N application decreased with delay in sowing. At early sowings there was a positive yield response to increasing N, whereas at the latest sowings in each season the N response was negative for all cultivars. Where the yield response to applied N was positive, the yield component most associated with yield was the number of florets per unit area (r = 0.55). Where the yield response was negative, yield reductions were primarily caused by a reduction in the proportion of filled grains (r = 0.83). Minimum temperatures during the reproductive stage of each cultivar explained only a small amount of the variation in percentage of filled grain. Low minimum temperatures during the reproductive stage were not the sole cause of the reduction in proportion of filled grains of late-sown, high-N plots. The high yield potential of short-duration cultivars in The high yield potential of short-duration cultivars in the New South Wales rice-growing area is clearly demonstrated, as is the value of such cultivars where late sowing is unavoidable.

scholarly journals The Effects of High-Temperature Weather on Human Sleep Quality and Appetite

2019 ◽  
Vol 16 (2) ◽  
pp. 270 ◽  
Author(s):  
Guozhong Zheng ◽  
Ke Li ◽  
Yajing Wang
Keyword(s):  
High Temperature ◽  
Sleep Quality ◽  
Maximum Temperature ◽  
Daily Maximum Temperature ◽  
Daily Maximum ◽  
Subjective Sleep Quality ◽  
Long Duration ◽  
Falling Asleep ◽  
Meal Time ◽  
C 32

High-temperature weather appears in high frequency, big strength, and long duration in the summer. It is therefore important to study the effects of high-temperature weather on sleep quality and appetite. Ten healthy college students were selected as subjects. The experiment conditions were divided by the daily maximum temperature into 28 °C, 32 °C, 36 °C, and 38 °C. The objective sleep quality was measured by an intelligent sleep monitoring belt, and the subjective sleep quality was measured by a questionnaire survey. The subjective appetites were assessed by a visual analog scale (VAS), and the objective appetites were assessed by the meal weight and the meal time. For sleep quality, the objective results indicated that the sleep quality at 32 °C was the best, followed by 28 °C, while the sleep quality at 36 °C and 38 °C was the worst. Significant effects were mainly reflected in sleep duration and shallow sleep. The subjective results showed that temperature had significant effects on sleep calmness, difficulty in falling asleep, sleep satisfaction, and sleep adequateness. For appetite, the VAS results indicated that high temperatures mainly led to a reduction of appetite at lunch time. The meal weights of lunch were larger than those of supper except for 28 °C, and the meal time of lunch and supper was longer than that of breakfast. The meal time of lunch was longer than that of supper except for 36 °C. This paper can provide a study method and reference data for the sleep quality and appetite of human in high-temperature weather.

Response of potassium nitrate on yield and yield contributing characters of boro rice cv. BRRI dhan28

2020 ◽  
Vol 01 (01) ◽  
pp. 05-13
Author(s):  
M. Hasan ◽  
M. B. Akter ◽  
M. M. Karim ◽  
F. Yasmine ◽  
A. K. Hasan
Keyword(s):  
Grain Yield ◽  
Foliar Application ◽  
Block Design ◽  
Foliar Spray ◽  
Potassium Nitrate ◽  
Growth And Yield ◽  
Growth Stages ◽  
Yield Production ◽  
Initiation Stage ◽  
Boro Rice

The experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh, to explore the growth and yield performance of boro rice cv. BRRI dhan28 is influenced by foliar spray of potassium nitrate (KNO3) at four rice growth stages. The experiment consisted of four doses of KNO3 viz. 0 (Control), 0.25, 0.50 and 1.00 kg ha−1 and applied at four growth stages of rice development viz. at panicle initiation, at ear emergence, at anthesis period and at dough stage. This experiment was carried out in Randomized Complete Block Design (RCBD) with three replications with 10 m2 (4.0 m × 2.5 m) unit plot size and spacing between blocks and unit plots was 1 m and 0.5 m, respectively. Results revealed that foliar application of potassium nitrate at four growth stages significantly affected yield and yield contributing characters of BRRI dhan28. But most of the yield contributing characters did not differ significantly due to the interaction between potassium nitrate and stage of foliar spray. However, the foliar application of KNO3 @ 0.25 kg ha−1 showed the highest yield production (5.86 kg ha−1) while the lowest yield (4.85 kg ha−1) was found in control. Furthermore, better yield performances were recorded when the KNO3 was applied at panicle initiation stage rather than the other four growth stages. The total number of tillers, 1000–grain weight and grain yield, was higher with foliar spraying of a 0.25 kg ha−1 KNO3 at panicle initiation stage. From this experiment, it may be concluded that foliar application of KNO3 affected the yield performances of BRRI dhan28 and 0.25 kg ha−1 KNO3 produced the highest grain yield when applied at panicle initiation stage of boro rice.

scholarly journals Investigation of low-temperature cofired ceramics packages for high-temperature SAW sensors

2016 ◽  
Vol 5 (1) ◽  
pp. 85-93
Author(s):  
Jochen Bardong ◽  
Alfred Binder ◽  
Sasa Toskov ◽  
Goran Miskovic ◽  
Goran Radosavljevic
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Acoustic Wave ◽  
Temperature Sensor ◽  
Elevated Temperatures ◽  
Failure Mechanisms ◽  
Maximum Temperature ◽  
Sensor Devices ◽  
Production Cycles ◽  
Cofired Ceramics

Abstract. Surface acoustic wave (SAW) temperature sensor devices have been developed for operating temperatures up to and above 1000 °C. A challenging task to make these devices available on the market is to develop an appropriate housing concept. A concept based on low-temperature cofired ceramics (LTCC) has been investigated and tested under elevated temperatures up to 600 °C. The devices showed promising results up to 450 °C. Thorough analysis of the possible failure mechanisms was done to increase the maximum temperature above this limit in further production cycles.

scholarly journals Impacto de las variaciones de temperatura diaria en la historia natural de los anuros tropicales

2016 ◽  
Vol 65 (1) ◽  
pp. 55 ◽  
Author(s):  
Manuel Hernando Bernal-Bautista ◽  
Jorge Luis Turriago-González ◽  
Francisco Antonio Villa-Navarro
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Variable Temperature ◽  
Developmental Time ◽  
Maximum Temperature ◽  
Medium Temperature ◽  
Variable Environment ◽  
Gosner Stage ◽  
C 23 ◽  
The Impact

Anuran embryos and tadpoles are daily exposed to wide thermal variations in their ponds, with maximum temperatures at midday. The aim of this research was to study the impact of three daily variable thermal environments (with maximum experimental temperatures between 10:00 and 16:00 hours), on the survival, developmental time and body size of metamorphs of four tropical anuran species from lowland habitats in Colombia. A total of 50 embryos (Gosner stage ten) to metamorphosis (Gosner stage 46) of Rhinella humboldti, Hypsiboas crepitans and Engystomops pustulosus were exposed to each one of the three daily variable temperature treatments: high temperature (mean = 27.5 °C; maximum temperature = 34 ± 1 °C; range = 23-35 °C), medium temperature (25.5 °C; 29 ± 1 °C; 23-30 °C), and low temperature (24 °C; 24 ± 1 °C; 23-25 °C). For the other species, Espadarana prosoblepon, 40 embryos to metamorphosis were exposed to each one of the following thermal treatments: high temperature (mean = 22 °C; maximum temperature = 25 ± 1 °C; range = 18-26 °C), medium temperature (20.5 °C; 22 ± 1 °C; 18-23 °C), and low temperature (19 °C; 19 ± 1 °C; 18-20 °C). For all species, the thermal variable environment with the highest temperature showed the greatest accumulated survival, reduced significantly the developmental time from embryos to metamorphs, and the snout-vent-length of metamorphs. Therefore, under field conditions where ponds are exposed to thermally variable environments, the highest temperatures may promote a decrease in the period of time to metamorphosis, and a positive increase for the anuran survival; nevertheless, extreme temperatures were also found in the microhabitat of the species studied, higher than their upper thermal limits reported, which suggest a vulnerable situation for them and other tropical anurans from similar habitats.

Thermo-Mechanical Storage of Electricity at Power Plant Scale

2013 ◽  
Author(s):  
Wolf-Dieter Steinmann
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Latent Heat ◽  
Heat Storage ◽  
Storage Systems ◽  
Storage System ◽  
Thermal Storage ◽  
Maximum Temperature ◽  
Latent Heat Storage ◽  
Temperature Heat

The availability of cost effective storage capacity is considered essential for increasing the share of renewables in electricity generation. With the development of solar thermal power plants large thermal storage systems have become commercial in recent years. Various storage concepts are applied, systems using solid storage media are operated at a maximum temperature of 680 °C, other systems using molten salt as storage medium show thermal capacities in the GWh range. Heating these storage systems directly by surplus electricity and using the heat later during the discharge process to operate turbines is not very attractive, since the process is limited by the Carnot efficiency. Alternatively, surplus electricity can be used to transform low temperature heat into high temperature heat which is stored in a thermal storage system during the charging process. During discharge, this heat is used to drive a turbine generating electric energy. Theoretically, this concept allows a roundtrip efficiency of 100%. Various options for the implementation of this storage concept have been suggested, using air or CO2 as working fluids. Recently, DLR has demonstrated the operability of a latent heat storage system connected to a steam circuit at 100 bar. The availability of this latent heat storage technology allows new implementations of the storage concept based on heat transformation. Using a left-running Rankine cycle during the charging process, heat from the environment is used to evaporate steam, which is compressed using the surplus electricity. Superheated steam exiting the compressor flows through the thermal storage system composed of latent heat storage sections and sensible heat storage sections. After throttling, the water enters the evaporator again. During discharging, heat from the storage system is used to evaporate and superheat steam, which drives the turbine. A cascaded implementation of this concept, using ammonia for the low temperature part of the process, while water is used for the high temperature part, reaches a storage efficiency of 70%. The integration of low temperature waste heat sources allows the compensation of losses.

scholarly journals Growth and yield of boro rice (Oryza sativa L.) in response to crop establishment methods and varieties

2020 ◽  
Vol 5 (2) ◽  
pp. 137-143
Author(s):  
Afrina Rahman ◽  
Md. Abdus Salam ◽  
Md. Abdul Kader ◽  
Md. Shafiqul Islam ◽  
Suriaya Perveen
Keyword(s):  
Grain Yield ◽  
Dry Matter ◽  
Oryza Sativa L ◽  
Direct Seeding ◽  
Growth And Yield ◽  
Growth Stages ◽  
Rice Cultivars ◽  
Area Index ◽  
Crop Establishment ◽  
Boro Rice

Physiological attributes and yield performance of high yielding varieties (HYV) of rice cultivars need to be assessed by crop establishment methods before promoting a suitable crop establishment method in Bangladesh. We, therefore, conducted an experiment to study the effects of crop establishment methods on the growth and yield of boro rice. The experiment comprised of two factors; factor A: methods of crop establishment viz., dry direct seeding, unpuddle transplanting, alternate wetting and drying (AWD) and puddle transplanting; factor B: rice cultivars viz., BRRI dhan28, BRRI dhan58, BRRI dhan74 and BRRI hybrid dhan3. The experiment was laid out in a split-plot design with three replications where method of crop establishment was assigned to the main plot and rice cultivar was assigned to the sub plots. Data were collected at different growth stages and at harvest. From the results, it was found that growth, yield and yield contributing characters were significantly influenced by crop establishment methods. The highest leaf area index (LAI), total dry matter and grain yield were found in puddle transplanting method. The highest grain yield was obtained in puddle transplanting method due to accumulation of maximum dry matter and production of highest number of effective tillers hill-1 and grains panicle-1. Among the varieties the highest grain yield was obtain in BRRI hybrid dhan3 due to highest number of grains panicle-1 and 1000-grain weight. The highest grain yield (6.21 t ha-1) was found in puddle transplanting with BRRI dhan28, while the lowest grain yield (2.80 t ha-1) was produced in dry direct seeding with BRRI dhan28. Therefore, puddle transplanting with BRRI dhan28 might be recommended due to best physiological performance and obtaining highest grain yield of boro rice.

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