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41.
In northern Laos, shortened fallows in the slash-and-burn upland rice system are not sustainable either from a production or economic standpoint. This paper evaluates the potential for using the indigenous fast-growing tree, Broussonetia papyrifera L. Vent. (paper mulberry) as an economic fallow crop. The objectives of this study are to assess the inner bark yield of paper mulberry, and to evaluate rice productivity following paper mulberry cultivation. In addition, allometric models for estimating the inner bark yield of paper mulberry are developed. Inner bark yield of paper mulberry stands ranging in age from 9 to 48 months ranged from 10 to 208 g m−2, and increased with age. The models using diameter at breast height and stem height, or diameter at breast height only as independent variables explained well the variation in inner bark yield. When paper mulberry was completely removed during the rice growing season, rice yields in these areas were similar to those following weedy bush fallow. When paper mulberry was allowed to grow, rice yields were negatively correlated to paper mulberry stem density. When paper mulberry lateral branches were pruned back, rice yields could be maintained if the paper mulberry stem density was <0.22 stems m−2, suggesting that if paper mulberry is managed properly, rice yields can be maintained at current levels. The paper mulberry-upland rice rotation system improves the productivity of a traditional slash-and-burn system through harvesting paper mulberry inner bark; however the long-term sustainability of such a system remains unclear and warrants further investigation.  相似文献   
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43.
The Arabidopsis CLAVATA3 (CLV3) gene encodes a stem cell-specific protein presumed to be a precursor of a secreted peptide hormone. Matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) applied to in situ Arabidopsis tissues determined the structure of a modified 12-amino acid peptide (MCLV3), which was derived from a conserved motif in the CLV3 sequence. Synthetic MCLV3 induced shoot and root meristem consumption as cells differentiated into other organs, displaying the typical phenotype of transgenic plants overexpressing CLV3. These results suggest that the functional peptide of CLV3 is MCLV3.  相似文献   
44.
This study was designed to develop a novel sandwich enzyme-linked immunosorbent assay (ELISA) for the detection and quantification of coconut milk proteins in processed foods. The developed sandwich ELISA was able to detect coconut milk proteins from various coconut milk products and did not show any cross-reactivity with 41 of 42 kinds of popularly used food ingredients, thus reflecting great specificity for coconut milk proteins. In addition, the established ELISA is highly sensitive and allowed the detection of 0.31 μg/g of coconut milk protein in complex food matrices. This proposed assay could serve as a useful tool for the detection of the presence of hidden coconut milk proteins in processed foods.  相似文献   
45.
ABSTRACT

Recently, US soybean cultivars have exhibited higher yields than Japanese soybean cultivars. To identify the determinants for this yield difference in reference to dry matter dynamics, recently developed US cultivars and Japanese commercial cultivars were cultivated in drained paddy fields in 2012 and 2013. The total dry matter (TDM) of each cultivar was measured at the initial seed-filling stage (R5), at 30 d after R5, and at maturity (R8). From R5 to R8, the DM of abscised leaves and petioles were measured. The actual HI (with abscised leaves and petioles) and apparent HI (without abscised leaves and petioles) were determined at R8. US soybean cultivars showed higher yields and apparent TDM (without abscised leaves and petioles) than did Japanese cultivars at R8. However, the difference in actual TDM (with abscised leaves and petioles) production was not significant between US and Japanese cultivars at R8. On the other hand, the actual HI was higher in US cultivars than in Japanese cultivars. US cultivars exhibited a higher TDM distribution to the pod before R5 and a higher pod growth rate from R5 to 30 d after R5. US cultivars tended to show greater crop growth rates (CGRs) from R5 to 30 d after R5. The higher yield in US cultivars was associated with the higher actual HI, which was considered attributable to a greater TDM productivity during the seed-filling period and higher DM distribution in the pod before R5.  相似文献   
46.
Cultivar tests under tropical environments could be an approach to explore soybean productivity under high temperature. Twenty-nine soybean cultivars divided into five groups with temperate origin (Japanese and US) and tropical origin (Indonesian-old, Indonesian-modern and other tropical) were grown for two years in a tropical environment at Banten, Indonesia, with minimal season-to-season variation in air temperature and day-length. Temperate cultivars were earlier in flowering and shorter in duration from R1 to R5. Temperate cultivars had a seed yield of 157 g m?2 (mean temperate cultivars) compared to 249 g m?2 (tropical cultivars), which was due to having lower values of pods, seed number and TDW. In addition, the occurrence of shriveling and smaller seed size compared to plants grown in their region of origin was considerably evident in Japanese cultivars. To account for the difference of growth duration, a maturity-corrected index for yield and relevant variables was calculated to consider the amount of incident solar radiation. The yield index for all tested cultivars ranged from .49 to 1.48, and Japanese cultivars showed the lowest yield index (.67), followed by US cultivars (.87), whereas tropical cultivars had index means from 1.05 to 1.20. Although they were both of temperate origin, Japanese cultivars tended to show a lower index than US cultivars. The tendency was similar for TDW and node number. The poor performance of temperate cultivars even after correction suggests that there is a genetic variation of adaptation to a tropical environment independent of growth duration. Additionally, there was considerable performance variation within temperate cultivars.  相似文献   
47.
A 12-year-old, intact female beagle exhibited symptoms of polyuria-polydipsia and hyperorexia for two months. Blood tests showed elevated asparate aminotransferase, alanine aminotransferase, alkaline phosphatase and creatine kinase levels, as well as marked hypokalemia. The results of adrenocorticotropic hormone stimulation test showed elevated cortisol, aldosterone and corticosterone concentrations. Abdominal ultrasonography confirmed a mass in the left adrenal gland. Masses were also seen in the liver and caudal vena cava. Diagnosis was a tumor of the adrenal cortex with metastases. Trilostane administration was initiated. The dog initially showed improved demeanor as a result of regulating hormone secretion. However, after 88 days, the dog weakened rapidly, before dying on the 117th day. Pathological findings confirmed a diagnosis of adrenocortical carcinoma.  相似文献   
48.
The objective of this study was to elucidate variability among soybean cultivars in yield response at different planting densities in reference to branch development. We investigated the main stem and branch seed yield and the branching characteristics of determinate Hokkaido and indeterminate US cultivars at the Rakuno Gakuen University in Ebetsu. In 2009 and 2010, two Japanese and two US cultivars were grown at three densities from 9.5 to 20 plants m?2. In 2011 and 2012, three cultivars from each region were cultivated at three densities from 8.3 to 22.2 plants m?2. The seed yields of the US cultivars at densities of 16.7 plants m?2 or less were markedly higher than those of the Hokkaido cultivars, showing that their yield is less sensitive to lower planting density than Hokkaido cultivars. The difference in yield in response to planting density among cultivars was closely associated with a larger increase in branch seed yield with lower planting density, which effectively compensated for the decrease in main stem number per unit land area. The variability of branch development in response to planting density (branching plasticity) was quantified by correlating branch performance with plant spacing (land area per plant). Some US cultivars exhibited greater branching plasticity than Japanese cultivars with similar growth duration. Results of this study suggest soybean cultivar differs in responsiveness to varied planting density through different branching plasticity.  相似文献   
49.
Erect panicle rice cultivars utilize solar energy effectively and have improved ecological growing conditions. Among such cultivars, Shennong265 has been grown successfully throughout Northern China. Nevertheless, no studies have yet examined the relationships between crop dry matter productivity, weather conditions, and nitrogen uptake of the erect panicle type rice cultivar in Japan. The objective of our study was to evaluate the productivity of erect panicle rice Shennong265 in Western Japan under varied conditions. Three rice cultivars, Shennong265, Nipponbare, and Takanari were grown in the field under different fertilizer and plant density conditions in Western Japan; using this information, we compared yield and growth characteristics of Shennong265 with those of Nipponbare and Takanari. Although Shennong265 had radiation use efficiency similar to that of the high yielding cultivar (Takanari) and much higher leaf nitrogen content than Takanari and Nipponbare, the average grain yield of Shennong265 grown under normal fertilizer and plant density conditions was approximately 6.9 t ha?1 as against 6.2 t ha?1 for Nipponbare and 9.6 t ha?1 for Takanari. These results suggest that, while Shennong265 has a high yield potential, the environmental conditions including climate, fertilizer, and planting period provided in this study were not suitable for achieving its maximum yield. The reduced performance of Shennong265 may be caused by insufficient fertilizer after heading and by shorter growth periods, as well as by the climate of Western Japan. Additional fertilizer application during the heading stage and earlier transplanting may be needed to obtain higher Shennong265 yields in Western Japan.  相似文献   
50.
Green stem disorder (GSD) in soybean (Glycine max (L.) Merrill) retains green stems and leaves as the pods mature, thereby reducing the harvest efficiency and impairing seed quality. In order to elucidate the causes of GSD, the factors that promote GSD need to be identified. In our experiments, we adjusted plant density at the developmental growth stage R1 (the beginning of flowering) or at R5 (the beginning of seed filling), from dense (22.2 plants m–2) to sparse (5.56 plants m–2) by thinning. We found that GSD occurrence was increased when plant density was changed, compared to the treatments that were maintained under either dense or sparse conditions. GSD was promoted more strongly when thinning was conducted at R5 than at R1 stage. Shading equipment surrounding plants, except for their upper-most leaves, was implemented to determine the association of shading and GSD. The results of the shade experiment revealed that GSD occurrence generally increased in treatments subjected to shade removal, compared to those that were shaded until R8 stage (full maturity) or never shaded since the time of sowing. GSD was strongly promoted by shade removal at R5 than at R1 stage. The shading results coincide with the results of the plant density experiment, indicating that an increase in light availability enhances source activity relative to sink at R5 stage, thereby promoting GSD occurrence in soybean. Thinning is expected to be used as an easy experimental method to create GSD for research purpose.  相似文献   
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