22 research outputs found
Temporal Growth Inhibition of Rice Plant and Growth Recovery Observed under Application of Anaerobically-DigestedCattle Manure
A field experiment assessing the effect of the annual application of anaerobically-digested cattle manure (ADM), produced at a biogas plant, on paddy rice was conducted. In plots with ADM (MF), the early growth of rice plants, from transplanting to the active tillering stage, was inhibited compared to the plots with chemical fertilizers (CF). This phenomenon was observed over many growing seasons and was especially obvious in nitrogen uptake and leaf area index (LAI). However, after panicle initiation, the growth of MF-treated plants was equal to or superior to CF-treated plants. The grain yield in all the MF plots was 96 – 105% of that in the CF plots. The inorganic nitrogen content of the soil in the MF plots was higher than that in the CF plots, which was contradictory to the growth inhibition observed in the initial growth of plants in the MF plots. In contrast, the oxidation/reduction potential and pH of the surface soil in MF plots were within the normal range, indicating that these soil factors were not associated with growth inhibition observed in MF plots. Our results implied that rice cultivars with a long growing period that are able to recover from the initial growth inhibition, such as medium or late maturing cultivars, are suitable for paddy rice production fertilized with ADM
Laparoscopic and endoscopic cooperative surgery for duodenal neuroendocrine tumor (NET) G1: Report of a case
INTRODUCTION: We report a case of duodenal neuroendocrine tumor (NET) G1 resected by laparoscopic and endoscopic cooperative surgery (LECS) technique.
PRESENTATION OF CASE: A 58-year-old woman underwent esophagastroduodenoscopy, revealing an 8-mm, gently rising tumor distal to the pylorus, on the anterior wall of the duodenal bulb. Endoscopic ultrasonography suggested the tumor might invade the submucosal layer. The tumor was pathologically diagnosed as a G1 duodenal NET, by biopsy. Endoscopic submucosal dissection was attempted, but was unsuccessful because of the difficulty of endoscopically performing an inversion operation in the narrow working space. The case was further complicated by the patient's duodenal ulcer scar. We performed a full-thickness local excision using laparoscopic and endoscopic cooperative surgery. The tumor was confirmed and endoscopically marked along the resection line. After full-thickness excision, using endoscopy and laparoscopy, interrupted full-thickness closure was performed laparoscopically.
DISCUSSION: Endoscopic treatment is generally recommended for G1 NETs <10 mm in diameter and extending only to the submucosal layer. However, some cases are difficult to resect endoscopically because the wall of duodenum is thinner than that of stomach, and endoscope maneuverability is limited within the narrow working space. LECS is appropriate for early duodenal G1 NETs because they are less invasive and resection of the lesion area is possible.
CONCLUSION: We demonstrated that LECS is a safe and feasible procedure for duodenal G1 NETs in the anterior wall of the first portion of the duodenum
Geostatistical Analysis of Yield, Soil Properties and Crop Management Practices in Paddy Rice Fields
Geostatistical Analysis of Yield, Soil Properties and Crop Management Practices in Paddy Rice Fields
We examined the possible benefit of rational site-specific crop management practices in 17 paddy fields located in an area of 2.0 ha for the prevalence of precision agriculture methods on a cooperatively managed large-scale farm in Sakurai, Nara Japan. Data on grain yield, soil physicochemical properties and farmer's crop management practices were collected in each paddy field. Unhulled rice yield was estimated at a resolution of 5m ą 5m in an area of 1.2 ha using a yield-monitoring combine. The spatial distribution of the variations for the collected data was characterized using geostatistical procedures. The kriged map of the unhulled rice yield drawn from the results of geostatistical analysis indicated the potential value of rational site-specific crop management using the yield-monitoring combine. The ratio of spatially structured variation to the total variation of brown rice yield, that is, the controllable proportion to total variation, was 75.4%. Each yield component i.e., the number of spikelets per square meter, filled-spikelet percentage and 1000-grain weight contributed 33.7%, 54.7% and 11.6%, respectively, to brown rice yield. These three yield components combined contributed to 96.5% of the brown rice yield variation. The agronomic factors (soil fertility factor, early growth factor, N dressing and uptake factor) contributed 79.7%, 52.1% and 41.8%, respectively, to the variation of these three yield components. Therefore these agronomic factors accounted for 58.1% of the total variation of the brown rice yield and 77.1% (i.e. 58.1% out of 75.4%) of the spatially structured variation of the brown rice yield. This controllable proportion may be a criterion for the prevalence of site-specific crop management in large-scale farm management in general, although only one case study was conducted
Effects of the Long-Term Application of Anaerobically-Digested Cattle Manure on Growth, Yield and Nitrogen Uptake of Paddy Rice (Oryza sativa L.), and Soil Fertility in Warmer Region of Japan
The suitability of anaerobically-digested manure (ADM) from a biogas plant, as an alternative to chemical fertilizers for rice cultivation was evaluated by a long-term study. At the standard nitrogen (N) application rate (10 g m−2), the aboveground biomass, N uptake, and grain yield in rice plots with ADM application (MF) were not significantly different from those in the plots treated with chemical fertilizer (CF). Split application of ADM improved the apparent N efficiency. The N application rate corresponding to maximum grain yield was approximately 15 g m−2 by a split application, and more N application by using ADM saturated grain yield due to decrease in ripened grain ratio and individual grain weight. On the whole, the soil total-C, total-N and available N in the MF plot were not significantly different from those in the CF plot. The available phosphate (P) levels was lower in the MF plot than in either the CF plot or plot without N application (NF), mainly due to lower content of P in ADM. However, the P level remained much higher than the fatal threshold level for the growth of paddy rice. These findings suggest that under appropriate fertilization conditions, ADM is a valuable organic resource, and can be used continuously as an alternative to chemical fertilization for rice cultivation, without substantial changes in soil C and N fertility