The Influence of Increasing Carbon Dioxide and Temperature on Competitive Interactions Between a C3 Crop, Rice (Oryza sativa) and a C4 Weed (Echinochloa glabrescens)

1996 ◽  
Vol 23 (6) ◽  
pp. 795 ◽  
Author(s):  
AMP Alberto ◽  
LH Ziska ◽  
CR Cervancia ◽  
PA Manalo
Keyword(s):  
Elevated Co2 ◽  
Growth Temperature ◽  
Competitive Ability ◽  
Relative Yield ◽  
Co2 Concentration ◽  
The Philippines ◽  
Replacement Series ◽  
Lower Growth ◽  
C4 Species ◽  
Lower Growth Temperature

Many of the most troublesome weeds in agricultural systems are C4 plants. As atmospheric CO2 increases it is conceivable that competitive ability of these weeds could be reduced relative to C3 crops such as rice. At the International Rice Research Institute (IRRI) in the Philippines, rice (IR72) and one of its associated C4 weeds, Echinochloa glabrescens, were grown from seeding to maturity using replacement series mixtures (100:0, 75:25, 50:50, 25:75, and 0:100, % rice:%weed) at two different CO2 concentrations (393 and 594 μL L-1) in naturally sunlit glasshouses. Since increasing CO2 may also result in elevated growth temperatures, the response of rice to each CO2 concentration was also examined at daylnight temperatures of 27/21 and 37/29�C. At 27/21�C, increasing the CO2 concentration resulted in a significant increase in above ground biomass (+47%) and seed yield (+55%) of rice when averaged over all mixtures. For E. glabrescens, the C4 species, no significant effect of CO2 concentration on biomass or yield was observed. When grown in mixture, the proportion of rice biomass increased significantly relative to that of the C4 weed at all mixtures at elevated CO2. Evaluation of changes in competitiveness (by calculation of plant relative yield (PRY) and replacement series diagrams) of the two species demonstrated that, at elevated CO2, the competitiveness of rice was increased relative to that of E. glabrescens. However, at the higher growth temperature (37/29�C), growth and reproductive stimulation of rice by elevated CO2 was reduced compared to the lower growth temperature. This resulted in a reduction in the proportion of rice:weed biomass present in all mixtures relative to 27/21�C and a greater reduction in PRY in rice relative to E. glabrescens. Data from this experiment suggest that competitiveness could be enhanced in a C3 crop (rice) relative to a C4 weed (E. glabrescens) with elevated CO2 alone, but that simultaneous increases in CO2 and temperature could still favour a C4 species.

Development of LPE process for fabrication of coated conductors

2000 ◽  
Vol 659 ◽  
Author(s):  
Teruo Izumi ◽  
Natsuro Hobara ◽  
Toru Izumi ◽  
Katsuya Hasegawa ◽  
Masahiko Kai ◽  
...  
Keyword(s):  
Growth Temperature ◽  
Recent Progress ◽  
High Growth ◽  
High Growth Rate ◽  
Coated Conductors ◽  
The Other ◽  
Lower Growth ◽  
The Difference ◽  
Lower Growth Temperature ◽  
Selection Of

ABSTRACTRecent Progress of development for coated conductors by the LPE technique was reviewed. Double layered LPE films were applied to the growth on metal substrates. In both cases of MgO- and NiO- buffers, the constructions were succeeded to grow on Hastelloy and Ni tapes, respectively. In the case of the MgO-buffer, the problem, which is the melting back of the 1st LPE layer during dipping for the growth of the 2nd LPE layer, was found. The problem was solved by means of the selection of the materials for each LPE layer to introduce the difference in the growth temperature for the 1st and the 2nd layers. The lower growth temperature for the 1st LPE layer than that for 2nd one is effective to avoid the problem. On the other hand, the double layered LPE films on Ni tapes revealed Tc of 85K. Concerning the long tape processing, the high growth rate of 1≈ was confirmed even without rotation using the long tape apparatus.

LPE Growth of Textured KNbO3 Film Using SrTiO3 Substrate and V2O5 Flux

2006 ◽  
Vol 11-12 ◽  
pp. 109-112
Author(s):  
T. Hibino ◽  
Kenichi Kakimoto ◽  
Hitoshi Ohsato
Keyword(s):  
Thin Films ◽  
Phase Diagram ◽  
Growth Rate ◽  
Liquid Phase ◽  
Surface Morphology ◽  
Liquid Phase Epitaxy ◽  
Growth Temperature ◽  
Film Growth ◽  
Lower Growth ◽  
Lower Growth Temperature

KNbO3 thin films were grown on (100) and (110) SrTiO3 substrates by liquid phase epitaxy (LPE) technique. The film orientation and surface morphology were characterized by XRD and AFM, respectively. The limited phase diagram of K2O-Nb2O5-V2O5 system was prepared by DTA measurement to investigate the effect of V2O5 flux on the LPE growth of KNbO3 film. The use of V2O5 flux enhanced a film growth rate at lower growth temperature.

scholarly journals Competitive ability of canola (Brassica napus var. oleifera) hybrids with black oat (Avena strigosa) in a subtropical environment

2021 ◽  
Vol 53 (2) ◽  
pp. 119-131
Author(s):  
Leandro Galon ◽  
Germani Concenço ◽  
Luciane Renata Agazzi ◽  
Felipe Nonemacher ◽  
Thais Stradioto Melo ◽  
...  
Keyword(s):  
Competitive Ability ◽  
Total Population ◽  
Co2 Concentration ◽  
Replacement Series ◽  
Data Set ◽  
Avena Strigosa ◽  
Internal Co2 ◽  
Infrared Gas Analyzer ◽  
Better Than ◽  
Subtropical Environment

The objective of this study was to assess the competitive ability of canola (Brassicanapus var. oleifera) hybrids in competition with black oat (Avena strigosa) in a subtropical environment. The experiments were conducted in a greenhouse where canola hybrids ‘Hyola 61,’ ‘Hyola 76,’ ‘Hyola 433,’ and ‘Hyola 571’ were tested individually for their competitive performance with black oat. The plant proportion between black oat and the canola hybrid was changed (100%:0%; 75%:25%; 50%:50%; 25%:75%; and 0%:100%) while keeping the total population of plants constant (20 plants plot‑1). Photosynthesis rate (μmol m-2 s-1), internal CO2 concentration (μmol mol-1), and  transpiration rate (mol H2O m-2 s-1) were assessed using an infrared gas analyzer 55 days after emergence. Leaf area (m2 m-2) and dry matter (g m-2) were also assessed on the same day. The data set was analyzed by the replacement series method for competition studies. There was evidence of intense competition between canola and black oat, independent of plant proportion. The competitive ability of canola was distinct among hybrids; Hyola 571 performed better than the others in the competition against black oat. Choosing the most competitive hybrid, such as Hyola 571, helps maintain high canola grain yield levels in areas infested with black oat. Highlights: There is difference in competition among canola hybrids against black oat; Hyola 571 performed better in the competition; Preference should be given for most competitive canola genotypes against weeds, and weed control should be carried out early in the critical period of interference; Aggressiveness is the most preponderant parameter in determining canola genotypes with superior ability in competition against weeds.

Effect of lower growth temperature on C incorporation in GeC epilayers on grown by MBE

2003 ◽  
Vol 16 (3-4) ◽  
pp. 473-475 ◽  
Author(s):  
M. Okinaka ◽  
Y. Hamana ◽  
T. Tokuda ◽  
J. Ohta ◽  
M. Nunoshita
Keyword(s):  
Growth Temperature ◽  
Lower Growth ◽  
Lower Growth Temperature

scholarly journals Influence of different barley varieties on competition and yield performance in barley-oats mixtures at two levels of nitrogen fertilization

1991 ◽  
Vol 63 (4) ◽  
pp. 341-351
Author(s):  
Kari Jokinen
Keyword(s):  
Competitive Ability ◽  
Relative Yield ◽  
Grain Protein Content ◽  
Pure Stand ◽  
Replacement Series ◽  
Yield Performance ◽  
Relative Significance ◽  
Barley Cultivars ◽  
Relative Yield Total ◽  
Stand Yield

Competition between barley and oats, and yield performance of mixtures were evaluated in a two component replacement series field experiment at two levels of nitrogen applications (80 kgN/ha and 120 kgN/ha). Three barley cultivars (Aapo, Agneta ja Ida) and one oats cultivar (Veli) were used. The competitive relationship was independent of the pure stand yield of the cultivar. Ida and Agneta were more competitive than oats irrespective of nitrogen dose. Ida was the most dominant variety which was very likely due to the early development of the seedlings. Oats was slightly more competitive than the shortest cultivar Aapo at high nitrogen, although barley seedlings emerged before oats. Thus the competitive ability of a cultivar was not determined by one character of the plant only. The competition in mixtures had a greater effect on number of generative shoots and number of grains per head than on grain weight. The results revealed that the yield per plant in mixtures may be even the same as in monoculture, but the relative significance of different yield components may vary. The grain and protein yield of mixtures did not differ significantly from the yield of the highest yielding component grown alone. However, the ratio of actual and expected yield and the relative yield total were in most cases higher than one, indicating that some yield advantage may have been achieved. The genotypic composition of the stand had the greatest influence on the grain protein content of oats.

scholarly journals The effect of site on competition and yield advantages of mixtures of barley and oats

1991 ◽  
Vol 63 (4) ◽  
pp. 353-359
Author(s):  
Kari Jokinen
Keyword(s):  
Field Experiment ◽  
Grain Yield ◽  
Protein Content ◽  
Competitive Ability ◽  
Relative Yield ◽  
Early Growth ◽  
Average Yield ◽  
Replacement Series ◽  
Relative Yield Total ◽  
Genotypic Structure

Competition between six-row barley cv. Agneta and oats cv. Veli, and yield advantages of the mixtures were evaluated in a replacement series field experiment. The experiment was situated in a sloping area. Although barley was lower yielding (grain yield) than oats when the components were grown in monoculture, barley was dominant in all mixtures irrespective of the site. The competitive ability of barley decreased from the less productive site (top) to the more productive site (bottom). The improved competitive ability of oats was likely due to the faster early growth of oats. The grain yield of the mixture was about 4°70 (p >0.05) greater than the yield of the highest yielding component (oats) grown in monoculture on the more productive sites. The grain yield of the mixture was greater than the average yield of the pure stands and also the relative yield total exceeded one irrespective of the site. The grain weight of the species was independent of the genotypic structure of the stands. The protein content of oats was the highest, being greater in mixtures than in monocultures. The protein yield and the protein content of the mixture was between the values for pure stands.

Comparison of TiN thin films grown on SiO2 by reactive dc magnetron sputtering and high power impulse magnetron sputtering

2011 ◽  
Vol 1335 ◽  
Author(s):  
F. Magnus ◽  
A. S. Ingason ◽  
O. B. Sveinsson ◽  
S. Olafsson ◽  
J. T. Gudmundsson
Keyword(s):  
Grain Size ◽  
Magnetron Sputtering ◽  
High Power ◽  
Growth Temperature ◽  
Dc Magnetron Sputtering ◽  
Lower Growth ◽  
Tin Films ◽  
Grain Sizes ◽  
Tin Thin Films ◽  
Lower Growth Temperature

ABSTRACTThin TiN films were grown on SiO2 by a reactive dc magnetron sputtering (dcMS) and high power impulse magnetron sputtering (HiPIMS) at range of temperatures from 45 to 600oC and the properties compared. The HiPIMS process produces denser films at lower growth temperature than does dcMS and the surface is much smoother for films grown by the HiPIMS process. The grain sizes of both orientations are smaller in HiPIMS grown films than in dcMS grown films. The [200] crystallites have smaller size than the [111] crystallites for all growth temperatures. For the dcMS process the grain size increases with increased growth temperature for both the [111] and [200] crystallites. For the HiPIMS process the [200] grain size increases monotonically with increased growth temperature, whereas the size of the [111] oriented grains decreases to a minimum for growth temperature of 400 oC after which it starts to increase with growth temperature.

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