Influence of Different Calcium Amendments upon Methane Emission under Na-salinized Paddy Soil

Symposium Pape

Influence of different Ca amendments on CH4 emission under Na-salinized paddy soil

Session 2: Nitrogen, Green House Gasses and Agricultur

Identification of 45 New Neutron-Rich Isotopes Produced by In-Flight Fission of a 238U Beam at 345 MeV/nucleon

A search for new isotopes using in-flight fission of a 345 MeV/nucleon 238U beam has been carried out at the RI Beam Factory at the RIKEN Nishina Center. Fission fragments were analyzed and identified by using the superconducting in-flight separator BigRIPS. We observed 45 new neutron-rich isotopes: 71Mn, 73,74Fe, 76Co, 79Ni, 81,82Cu, 84,85Zn, 87Ga, 90Ge, 95Se, 98Br, 101Kr, 103Rb, 106,107Sr, 108,109Y, 111,112Zr, 114,115Nb, 115,116,117Mo, 119,120Tc, 121,122,123,124Ru, 123,124,125,126Rh, 127,128Pd, 133Cd, 138Sn, 140Sb, 143Te, 145I, 148Xe, and 152Ba

Investigating nuclear shell structure in the vicinity of 78Ni: Low-lying excited states in the neutron-rich isotopes 80,82Zn

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Effects of Soil Moisture Conditions before Heading on Growth of Wheat Plants under Drought Conditions in the Ripening Stage: Insufficient Soil Moisture Conditions before Heading Render Wheat Plants More Resistant to Drought during Ripening

Plants growing on soil with insufficient moisture need deep and dense roots to avoid water stress. In crop plants, the production of dry matter during ripening of grains is critically important for grain yield. We postulated that shoot growth would be suppressed but root growth would continue under an insufficient soil moisture condition before heading, while shoot growth would be more vigorous than root growth under a sufficient soil moisture condition. We anticipated that the plants growing under an insufficient soil moisture condition before heading would produce more dry matter and grain under an insufficient soil moisture condition during ripening. In order to examine our hypotheses and to determine the fundamental conditions for improving grain yield and efficient use of irrigated water under limited irrigation, we grew wheat plants (Triticum aestivum L., cv. Ayahikari) in pots (30 cm in diameter, 150 cm in height) with insufficient soil moisture (PD-D pots) or sufficient soil moisture (PW-D pots) for six weeks before heading followed by full irrigation, and then insufficient soil moisture condition during ripening. The growth of shoots was suppressed significantly but that of roots was not before heading in PD-D plants, with a higher resultant ratio of root to shoot than in PW-D plants. The former retained a high leaf water potential and, therefore, were able to produce more dry matter and grain during soil moisture depletion during ripening as compared with the latter plants. We also obtained similar results with field-grown plants

Completely engaged three-dimensional mandibular gear-like structures in the adult horned beetles: reconsideration of bark-carving behaviors (Coleoptera, Scarabaeidae, Dynastinae)

Adult horned beetles (Coleoptera, Scarabaeidae, Dynastinae) such as Trypoxylus dichotomus (Linnaeus, 1771) exhibit bark-carving behaviors to feed on tree sap, in part by using small projections of the clypeus. However, in the present experiments, adult horned beetles (T. dichotomus and Dynastes hercules (Linnaeus, 1758)) used their mandibles and not the projections of the clypeus to carve bark. Our findings show the presence of completely engaged mandibular interlocking, gear-like surface structures in molar areas that guide mandible opening and closure, and lead to completely synchronous movements of adult horned beetle mandibles. Three-dimensional shapes of these mandibular gear-like structures are complex and remained in contact after the death of a beetle. Moreover, adult horned beetles often performed bark-carving behaviors using only the mandible of one side, suggesting that the primary role of the mandibular gear-like structure is to prevent breakage of the mandible by transmitting load from one mandible to the other. Among the 22 Dynastinae and 16 other beetle species examined (not Dynastinae), the gear-like structure was found in all the Dynastinae species and in no other species

イミダクロプリドの製剤および施用方法の違いが 水田に生息する水生昆虫に及ぼす影響

The abundance of larvae of midge and mayfly, Cloeon dipterum (Linnaeus), in paddy plots with conventional release granular formulation corresponding to before transplanting treatment in nursery boxes(BT treatment), was significantly lower than in control plots 14 days after transplanting (DAT), but species abundance in BT plots was significantly higher than in control plots at 28 DAT. On the other hand, there were no significant differences in the abundance of aquatic insects, including midge and mayfly larvae, in paddy plots with controlled release granular formulation, corresponding to at sowing treatment in nursery boxes (AS treatment), and control plots at 14 and 28 DAT. Moreover, for introduced nymphs of ferocious water bug, Appasus japonicas Vuillefroy, paralysis occurred in greater frequency in BT plots than in AS plots

Behavior of simetryn and thiobencarb in rice paddy lysimeters and the effect of excess water storage depth in controlling herbicide run-off

Eight small-scale lysimeters with different excess water storage depths (EWSDs) were used to investigate the behavior of two herbicides, simetryn and thiobencarb, under paddy conditions. The concentration of simetryn dissipated similarly in all the lysimeters, while the thiobencarb concentration varied significantly because thiobencarb can adsorb onto the dissolved organic matter in a manure slurry, which was applied to six of the lysimeters. The herbicide losses (the percentage of the applied mass) from the lysimeters were reversely proportional with the EWSD. The correlation was stronger for simetryn than for thiobencarb. An appropriate EWSD is required to effectively prevent herbicide run-off from the paddy field, especially when a rainfall event occurs soon after herbicide application

Effects of Planting Pattern on the Interception of Solar Radiation by the Canopy and the Light Extinction Coefficient of the Canopy in Rice Plants Direct-sown in a Submerged Paddy Field

In order to investigate effects of planting pattern on the interception of solar radiation by the canopy and the light extinction coefficient of the canopy in rice, the rice plants direct-sown in a submerged paddy field were grown in six planting patterns (A through F). In plots A, B and C, the planting density was 20.7 hills m-2 (22 cm × 22 cm spacing) with five, three and one plant per hill, respectively, and in plots D, E and F, the planting density was 82.6 hills m-2 (11 cm × 11 cm spacing), 44.4 hills m-2 (15 cm × 15 cm spacing), and 44.4 hills m-2 (7.5 cm × 30 cm spacing), respectively, with one plant per hill. At the tillering stage, the greater the tiller number and leaf area index, the larger the interception of solar radiation by the canopy. The tiller number was larger in the plots with one plant per hill, higher plant density and square arrangement of hills. At the early ripening stage, the light extinction coefficient of the canopy was smaller in such plots. The larger the average inclination of leaf blades, the smaller the light extinction coefficient of the canopy. The difference in stem inclination in the canopy might be responsible for the difference in the inclination of leaf blades. In the plots with one plant per hill, higher plant density and square arrangement of hills, stems were more erect. Within the range of planting patterns in our study, both the rate of interception of solar radiation by the canopy and the light-intercepting characteristics were significantly more favorable in the plots with one plant per hill, higher density and a square arrangement of hills