English
In this study the effect of carbon dioxide on the physiological and sanitary quality of rice seed during storage is reported. The experimental design was completely randomized in a 2x3x3 factorial arrangement, with two cultivars (Irga 423 and 424), three concentrations of carbon dioxide (0, 25 and 50%) and three storage periods (15, 30 and 45 days). According to the results, it was found that carbon dioxide maintains germination and vigor, and reduces mycoflora associated with the seed. The incidence of Aspergillus sp., Fusarium sp. and Rhizoctonia sp. was reduced respectively in proportions of 50%, 75% and 100%, when the seeds were submitted to the a 50% concentration of carbon dioxide for 45 days storage. As regards seed-seedling transmission, only the fungus was able to promote Bipolaris sp. disease in seedlings from seeds treated with carbon dioxide. In this context, carbon dioxide is a viable alternative for maintaining the quality of rice seeds during storage.
- Research Article
5
- 10.1016/1352-2310(96)00004-0
- Sep 1, 1996
- Atmospheric Environment
Characteristics of the large-scale circulation during episodes with high and low concentrations of carbon dioxide and air pollutants at an arctic monitoring site in winter
- Research Article
- 10.1155/2022/9622688
- Jul 12, 2022
- Advances in Multimedia
The quality of rice seed is very important for rice production. In the process of rice seed production, seed drying is an important link in the whole process of seed quality control, and the problems in mechanical drying are important factors affecting the quality of rice seed. It is easy to encounter rain weather when the sterile seeds are dried by natural air, which seriously affects the seed vigor. High-quality rice seed is an important guarantee to achieve high yield of rice, and seed germination rate is one of the factors directly affecting rice yield. The drying process has the greatest effect on the quality and germination rate of sterile rice seeds. Selecting reasonable drying technology is an important means to ensure the germination rate of sterile rice seeds. In this paper, the dewatering and drying technology of rice sterile line seeds in intelligent baking room was studied. An adaptive integral sliding mode control algorithm based on Smith prediction was proposed for intelligent baking room temperature. The lag in the system was compensated by Smith prediction; the uncertainty of the system model and the complex interference under variable operating conditions were overcome by the robustness of sliding mode control. And the chattering of the sliding mode was eliminated by the adaptive integral sliding mode surface. The seeds of three rice varieties were dried, the drying dehydration rate, seed germination rate, and seed vigor were measured, and the changes of seed moisture and temperature during drying were observed. The results showed that there was little difference in the seed vigor after drying and air dried, which proved that the dryer could be used to dry different kinds of male sterile seeds. Compared with air dried seeds, the germination rate and germination potential of all mechanically dried seeds have little difference, and the overall difference of germination index and vitality index is also small. This study solved the problem that the seeds of male sterile lines could not be dehydrated and dried in time of rainy weather, which is of great significance to improve seed quality and economic benefits.
- Research Article
3
- 10.4236/ajps.2015.612193
- Jan 1, 2015
- American Journal of Plant Sciences
In the final stages of a plant breeding program, a crucial step is the multiplication of seeds in production fields. Besides a solid planning, the seeds multiplication needs a special attention to guarantee seeds with high quality, genetic integrity, high germination and vigor to the farmer. The aim of this study was to evaluate the physiologic quality, enzymatic expression and respiratory activity of seeds of 20 elite upland rice lines adapted to the state of Minas Gerais, Brazil, from the upland rice breeding program from three Brazilians research institutions. The quality parameters evaluated were root protrusion, number of normal seedlings in the germination test, number of normal seedlings in the germination first count, initial stand from emergence test, speed of emergence index, seedlings shoot and root length, percentage of O2 and CO2 from respiratory activity and the expression pattern of the enzymes alcohol dehydrogenase (ADH) and malate dehydrogenase (MDH). The seeds quality varied among lines, allowing the selection of lines with best performance. The respiratory activity was lower in seeds of lines with high quality. The enzyme ADH was an excellent marker to infer about the quality of seeds, and the variation in the expression of MDH did not depend on the quality of rice seeds. The lines BRS Esmeralda, CMG1896 and CMG1509 showed high physiologic quality in their seeds, and therefore, they should receive higher attention in rice breeding programs.
- Preprint Article
- 10.32920/ryerson.14657961
- Jun 8, 2021
Diffusivity is a strong function of concentration and an important transport property. Diffusion of multiple species is far more frequent than the diffusion of one species. However, there are limited experimental data available on multi-component diffusivity. The objective of this study is to develop an optimal control framework to determine multi-component concentration-dependent diffusivities of two gases in a non-volatile phase such as polymer. In Part 1 of this study, we derived a detailed mass-transfer model of the experimental diffusion process for the non-volatile phase to provide the temporal masses of gases in the polymer. The determination of diffusivities is an inverse problem involving principles of optimal control. Necessary conditions are determined to solve this problem. In Part 2 of this study, we utilized the results of Part 1 to determine the concentration-dependent, multi-component diffusivities of nitrogen and carbon dioxide in polystyrene. To that end, solubility and diffusion experiments are conducted to obtain necessary data. In the ternary system of nitrogen (1), carbon dioxide (2), and polystyrene (3), the diffusivities and D11, D12, D21, and D22 versus the gas mass fractions are two-dimensional surfaces. The diffusivity of carbon dioxide was found to be greater than that of nitrogen. The value of the main diffusion coefficient D11 was found to increase as the concentration of carbon dioxide increased. The highest value of D11 obtained was 2.2 X 10^-8m^2s^-1 for nitrogen mass fraction of 3.14 X10^-4 and for a carbon dioxide mass fraction of 5.67 X 10^-4 . The cross-diffusion coefficient increased as the concentrations of nitrogen and carbon dioxide increased. The diffusivity reached its maximum value when the concentrations of nitrogen and carbon dioxide were at their maximum values. The diffusivity was of the order of 10^-9m^2s^-1. The diffusivity of the cross-diffusion coefficient D21 was found to be increased for the mass The diffusivity of the cross-diffusion coefficient was found to be increased for the mass fractions of carbon dioxide ranging from 0 to 1.70 X 10^-3 . The diffusivity was found to be of the order of . The diffusion coefficient, D22, was found to increase with the concentrations of nitrogen and carbon dioxide, D22 remained high with low concentrations of carbon dioxide. The diffusivity was found to be of the order of 10^-7m^2s^-1
- Preprint Article
- 10.32920/ryerson.14657961.v1
- Jun 8, 2021
Diffusivity is a strong function of concentration and an important transport property. Diffusion of multiple species is far more frequent than the diffusion of one species. However, there are limited experimental data available on multi-component diffusivity. The objective of this study is to develop an optimal control framework to determine multi-component concentration-dependent diffusivities of two gases in a non-volatile phase such as polymer. In Part 1 of this study, we derived a detailed mass-transfer model of the experimental diffusion process for the non-volatile phase to provide the temporal masses of gases in the polymer. The determination of diffusivities is an inverse problem involving principles of optimal control. Necessary conditions are determined to solve this problem. In Part 2 of this study, we utilized the results of Part 1 to determine the concentration-dependent, multi-component diffusivities of nitrogen and carbon dioxide in polystyrene. To that end, solubility and diffusion experiments are conducted to obtain necessary data. In the ternary system of nitrogen (1), carbon dioxide (2), and polystyrene (3), the diffusivities and D11, D12, D21, and D22 versus the gas mass fractions are two-dimensional surfaces. The diffusivity of carbon dioxide was found to be greater than that of nitrogen. The value of the main diffusion coefficient D11 was found to increase as the concentration of carbon dioxide increased. The highest value of D11 obtained was 2.2 X 10^-8m^2s^-1 for nitrogen mass fraction of 3.14 X10^-4 and for a carbon dioxide mass fraction of 5.67 X 10^-4 . The cross-diffusion coefficient increased as the concentrations of nitrogen and carbon dioxide increased. The diffusivity reached its maximum value when the concentrations of nitrogen and carbon dioxide were at their maximum values. The diffusivity was of the order of 10^-9m^2s^-1. The diffusivity of the cross-diffusion coefficient D21 was found to be increased for the mass The diffusivity of the cross-diffusion coefficient was found to be increased for the mass fractions of carbon dioxide ranging from 0 to 1.70 X 10^-3 . The diffusivity was found to be of the order of . The diffusion coefficient, D22, was found to increase with the concentrations of nitrogen and carbon dioxide, D22 remained high with low concentrations of carbon dioxide. The diffusivity was found to be of the order of 10^-7m^2s^-1
- Research Article
2
- 10.5539/jas.v11n12p22
- Jul 31, 2019
- Journal of Agricultural Science
The hydric resources are primordial for plants growth and development, under conditions where the growing environment express hydric shortage. These conditions can directly or indirectly affect development, the formation of new organs, yield and quality seeds. The study aimed to evaluate the physiological quality of rice and soybean seeds, produced under hydric restriction. Experiment 1: for rice, the scheme was completely randomized with four repetitions, the treats of hydric restrictions were applied in the periods of 0, 24, 48, 72 hours at the phenological stage of filling seeds. Experiment 2: for soybean, the scheme was completely randomized, conducted in factorial scheme, four replicates with four hydric restriction periods of 0, 24, 48 and 72 hours, at the phenological stage of filling seeds. It was verified that as the hydric restriction hours increase, at the rice seeds filling, the physiologic quality is affected, the higher effect occurred at 72 hours of restriction. While at the soybean seeds production it was not verified such effects, only the thousand seeds mass was negatively affected. The physiological quality of rice seeds were more affected, when compared to soybean seeds submitted to the same treats of hydric stress.
- Research Article
12
- 10.1360/tb-2019-0022
- Nov 19, 2019
- Chinese Science Bulletin
The increase in carbon dioxide in the atmosphere is one of the main causes of global warming. Remote sensing technology has become an important means of monitoring the distribution of carbon dioxide gas. By remotely monitoring the temporal and spatial distributions of atmospheric carbon dioxide, people can further deepen their understanding of the global carbon process. The GOSAT (Greenhouse Gases Observing SATellite) CO2 L4B concentration data from 2010 to 2015 were validated using local station atmospheric data. The spatial and temporal distributions of the carbon dioxide concentration and its variation characteristics were analyzed. Based on the total primary productivity data and human emissions of carbon dioxide data, the influencing factors of spatial variations in carbon dioxide were analyzed. The results show that: (1) The correlation coefficient between GOSATL4B data and ground-measured data is above 0.95, which indicates that the remotely acquired data have high precision and stability. (2) The spatial distribution characteristics of carbon dioxide at different atmospheric pressure heights are quite different. The variation in the long-term series mean of carbon dioxide concentration levels at 17 vertical heights was studied. The fluctuations in concentration changes at different height levels vary, and the closer to the surface, the greater the fluctuation is. The near-surface carbon dioxide concentration (975 hPa) has the largest fluctuation. When the atmospheric pressure is low (for example, 150 or 100 hPa), the high carbon dioxide concentration region is banded and concentrated near the equator. The trends in carbon dioxide concentration over land and sea surfaces are similar, and the common pattern is that the concentration of carbon dioxide has been increasing. (3) The near-surface carbon dioxide concentration (975 hPa) has clearly different spatial characteristics. There are four high-value centers across the globe: East Asia, western Europe, the US East Coast, and Central Africa. The concentration of carbon dioxide in the Northern Hemisphere near the ground is higher than that in the Southern Hemisphere. The fluctuation in the Southern Hemisphere is relatively small, and the trend is opposite that in the Northern Hemisphere. (4) The concentration of carbon dioxide showed a significant growth trend during the study period. By studying the change characteristics of the monthly global average at the 975 hPa level (approximately 300 m above sea level) from January 2010 to October 2015, it can be seen that the global CO2 concentration has been above 400 ppm for most of the year, and it is increasing each year. (5) Compared with the Southern Hemisphere, the cyclical changes in carbon dioxide concentration in the Northern Hemisphere are obvious and large, while the trend in the Southern Hemisphere is relatively stable, and the change is small. There are opposite trends in the cyclical changes in the carbon dioxide concentration in the Northern and Southern Hemispheres. When the carbon concentration in the Northern Hemisphere resides over the annual high-value area, the Southern Hemisphere has a low-value area of carbon dioxide concentration every year. In addition, the change in carbon dioxide concentration during the year is obvious with seasonal changes. This should be related to changes in vegetation phenology and different seasons in the Northern and Southern Hemispheres. (6) Four countries in East Asia (Korea, Mongolia, Japan and China) from 2010 to 2014 were selected to analyze the relationship between GPP (gross primary production) and near-surface carbon dioxide concentration. These two factors have a significant inverse correlation. When carbon dioxide is at a minimum, the GPP is at its peak, and when carbon dioxide reaches its peak, the GPP reaches a minimum. The above relationship fully indicates that terrestrial ecosystems play an important role as carbon sink contributors in the carbon cycle. (7) The relationship between atmospheric carbon dioxide and carbon dioxide data from human activities from the Global Atmospheric Research Emissions Database was analyzed. The former is significantly and positively correlated with carbon dioxide emissions caused by human activities, indicating that human activities are an important factor in the increase in carbon dioxide.
- Research Article
121
- 10.1017/s0007485300051221
- Jun 1, 1991
- Bulletin of Entomological Research
Lactic acid, carbon dioxide and human sweat stimuli were presented singly and in combination to femaleAedes aegypti(Linnaeus) within a wind-tunnel system. The take-off, flight, landing and probing responses of the mosquitoes were recorded using direct observation and video techniques. The analyses determined the nature of the response to different stimuli and the concentration ranges within which specific behaviours occurred. A threshold carbon dioxide concentration for taking-off of approximately 0.03% above ambient was detected. Lactic acid and human sweat samples did not elicit take-off when presented alone, however, when they were combined with elevated carbon dioxide, take-off rate was enhanced in most of the combinations tested. Flight activity was positively correlated with carbon dioxide level and some evidence for synergism with lactic acid was found within a narrow window of blend concentrations. The factors eliciting landing were more subtle. There was a positive correlation between landing rate and carbon dioxide concentration. At the lowest carbon dioxide concentration tested, landing occurred only in the presence of lactic acid. Within a window of low to intermediate concentrations, landing rate was enhanced by this combination. At the highest carbon dioxide concentration, landing was however inhibited by the presence of lactic acid. The sweat extract elicited landings in the absence of elevated carbon dioxide. This indicated the presence of chemical stimuli, other than lactic acid, active in the short range. Probing occurred only at low carbon dioxide concentrations and there was no probing when lactic acid alone was tested. There was however probing in the presence of combined stimuli, the level of response seemed to be positively correlated with the ratio of carbon dioxide and lactic acid concentrations.
- Research Article
14
- 10.1002/j.1537-2197.1940.tb14706.x
- Jul 1, 1940
- American Journal of Botany
ASSIMILATION AND RESPIRATION OF EXCISED LEAVES AT HIGH CONCENTRATIONS OF CARBON DIOXIDE
- Research Article
11
- 10.7158/14488388.2013.11464865
- Jan 1, 2013
- Australian Journal of Multi-disciplinary Engineering
To identify the most practical and representative sampling locations for air quality and environmental variables inside intensive piggery buildings, the variation in the spatial, diurnal and seasonal concentration of major airborne pollutants, and related environmental parameters, were analysed over a 2.5-day period at several locations within different piggery buildings. Major airborne pollutants including, ammonia, carbon dioxide, and airborne particles were monitored along with environmental parameters of airspeed, temperature and humidity. To determine the air quality within each building, cyclone attachments were installed to measure particles of less than 5 mm along with a seven hole sampler attachment to measure inhalable airborne particles. An Osiris optical particle counter also monitored the concentrations of airborne particles. Ammonia and carbon dioxide were monitored using a multi-gas monitoring machine and airspeed was measured using a hot-wired anemometer. Interesting patterns in the concentration of carbon dioxide, dust and ammonia were observed over time and space. Carbon dioxide, airspeed and dust concentration demonstrated an obvious circadian pattern. The difference in the concentrations of ammonia and carbon dioxide was not statistically significant at alternative sampling locations inside each building. However, the gravimetric measurements indicated that the concentrations of inhalable particles were not uniform throughout the buildings and proved to be higher above the walkways. Ammonia and respirable particle concentrations were significantly higher in summer when compared to winter conditions. These results combined, identified the most appropriate sampling times and sampling places for reliable evaluation of air quality in intensive livestock buildings.
- Research Article
5
- 10.2174/2212798410666181120122624
- Sep 18, 2019
- Recent patents on food, nutrition & agriculture
Among stone fruit, the peach (Prunus persica (L) Batsch) is one of the most widely grown species in Brazil, in both area cultivated and in production. The aim of this study was to evaluate the physiological quality of heavy and light seeds of four cultivars of Prunus persica for two storage periods, from tests of electrical conductivity, germination, and an analysis of initial plantlets growth. The Electrical Conductivity test (EC) was conducted in a Completely Randomised Design (CRD), in a 4 x 2 x 5 factorial scheme with five replications. The germination test was carried out in CRD, in a 4 x 2 factorial scheme with eight replications. The physiological quality of the seeds was determined at zero and twelve month's storage. For the growth analysis, the experimental design was in CRD, in a 4 x 2 factorial scheme with four replications. Under the conditions of the present study, it was found that the tests of germination and electrical conductivity were complementary in evaluating physiological quality in seeds of Prunus persica rootstock, suggesting that independent of the weight of the seeds, in 'Capdeboscq', 'Aldrighi', 'Okinawa' and 'Okinawa Roxo', there is a loss of quality and viability when the seeds are stored for a period of 12 months. Under the experimental conditions of the present study, it was concluded that storage for a period of 12 months in Recent patents is not rather recommendable for maintaining quality and viability in seeds of Prunus persica of the Capdeboscq, Aldrighi, Okinawa and Okinawa Roxo cultivars.
- Research Article
1
- 10.14295/cs.v8i2.1779
- Feb 1, 2018
- Comunicata Scientiae
The experiments were carried out under controlled conditions to evaluate the impact of increased temperature and concentration of carbon dioxide on infection of Xanthomonas campestris pv viticola, the causal agent of bacterial canker in Vine seedlings. It proceeded the evaluation of the following epidemiological components: incubation period (PI), severity (SEV) and using that data were calculated the area under the disease progress curve (AUDPC). It used grape seedlings (Italia, Crimson Seedless, Sugraone and Selection 8) inoculated with bacterial suspension (108 CFU mL-1). The experimental design was completely randomized, factorial arrangement 4x4 (cultivar x temperature) and 4x2 (cultivar x carbon dioxide concentration) which was carried out twice. The data were subjected to variance analysis. Increasing temperature reduced bacterium’s incubation period with significant differences between genotypes. For Selection 8 and Crimson temperature increase caused enhancement on severity and AUDPC. For Seleção 8 the incubation period (PI) was extended from 7.93 to 30.18 days when the concentration changed from 390 to 770 µmol/mol. The increased CO2 concentration reduced AACPSD and SEV for Sugraone and Selection 8. The results show that the temperature and carbon dioxide (CO2) concentration of the air may have different effects on bacterial canker of grapevine.
- Research Article
12
- 10.1071/ar9630765
- Jan 1, 1963
- Australian Journal of Agricultural Research
In the past, experiments on controlled atmosphere storage have tested specific combinations of carbon dioxide and oxygen, usually in a manner which precludes determination of the effect of change in concentration of these gases. The data from the series of trials discussed in this paper permitted an investigation of the effect of concentrations of carbon dioxide and oxygen on the incidence of scald with simple and multiple linear regression techniques. The method was applied to data from three types of controlled atmosphere storage: (1) Carbon dioxide 2.5–10% at 2.5% oxygen, (2) Oxygen 1.25–20%, at near zero carbon dioxide, (3) Carbon dioxide 3.3–10.9% oxygen 2.2–16%. The relation between scald (Y), carbon dioxide concentration (x), and the reciprocal of oxygen concentration (z), was described by the regression equation: Y = y + b(x – x) + c(z – z), which implies that scald is directly proportional to carbon dioxide concentration and indirectly proportional to oxygen concentration. The effects of changes in concentration of the gases, as estimated by the regression coefficients, were consistent for size of fruit, season, and orchard, but the effect for oxygen was dependent on the method of maintaining the atmosphere. Good control of scald was obtained with low oxygen atmospheres, even after storage for 6–7 months.
- Research Article
11
- 10.3390/atmos13071130
- Jul 17, 2022
- Atmosphere
The air environment (e.g., high concentration of carbon dioxide) in a pig house will affect the health conditions and growth performance of the pigs, and the quality of pork as well. In order to reduce the cumulative concentration of carbon dioxide in the pig house, the prediction model was established by the deep learning method to predict the changes of the carbon dioxide cumulative concentration in a pig house. This model will also be used for the real-time monitoring and adjustment of the concentration of carbon dioxide of the pig house. The experiment was designed to collect environmental parameters (e.g., temperature, humidity, wind speed, and carbon dioxide concentration) data in the pig house for several months. The ensemble empirical mode decomposition–gated recurrent unit (EEMD–GRU) prediction model was established in the prediction of carbon dioxide concentration in the pig house. The results show that compared with the other models, the prediction accuracy of the EEMD–GRU model is the highest, and the root mean square error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE), and r-squared (R2) of carbon dioxide concentration in autumn and winter are 123.2 ppm, 88.3 ppm, 3.2%, and 0.99, respectively. The RMSE, MAE, MAPE, and R2 for carbon dioxide concentration are 129.1 ppm, 93.2 ppm, 5.9%, and 0.76 in spring and summer. The prediction model proposed in this paper can effectively predict the concentration of carbon dioxide in the pig house and provide effective help for the precise control of the pig house environment.
- Research Article
61
- 10.2307/1536264
- Mar 1, 1918
- The Biological Bulletin
STUDIES IN THE PHYSIOLOGY OF SPERMATOZOA