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21.
The soil temperature regime map provides for utilitarian classification that can be superimposed on soil classification to permit more precise interpretations and assessments of land use. The objects of this study are (1) to clarify the relationship between soil temperature and meteo-geographical factors, and then (2) to delineate detailed soil temperature regime map (1?km grid) as Japanese land resources inventory. There was a parallel relationship between mean annual soil temperature (MAST) and mean annual air temperature (MAAT), but this relationship was affected to some extent by the mean annual wind speed and mean annual global irradiation in this study. Furthermore, the difference between MAST and MAAT [Diff(MAST–MAAT)] showed the highest correlation with elevation. The map of RK_Diff(MAST–MAAT) was computed using this meteo-geographical relationship with the regression-kriging approach, and then the map of MAST and the soil temperature regime map were delineated using the map of MAAT and the RK_Diff(MAST–MAAT). The root mean square error of this delineation procedure was 0.47°C. It was clear that the majority of the Japanese soils had “mesic” soil temperature regime, and Japanese agricultural land was mainly distributed at “mesic” area and followed by “thermic”, “frigid”, and “hyperthermic” area. For promoting this land resource inventory, the soil temperature regime map will be uploaded on “Soil Information Web Viewer (http://agrimesh.dc.affrc.go.jp/soil_db/)”, which is provided by the National Institute for Agro-Environmental Sciences.  相似文献   
22.
Iron (Fe) deficiency is a serious agricultural problem, especially in calcareous soils, which are distributed worldwide. Poplar trees are an important biomass plant, and overcoming Fe deficiency in poplars will increase biomass productivity worldwide. The poplar Fe-deficiency response and the genes involved in poplar Fe homeostasis remain largely unknown. To identify these genes and processes, we cultivated poplar plants under Fe-deficient conditions, both in calcareous soil and hydroponically, and analyzed their growth rates, leaf Soil and Plant Analyzer Development (SPAD) values, and metal concentrations. The data clearly showed that poplars have notable growth defects in both calcareous soil and a Fe-deficient hydroponic culture. They exhibited serious chlorosis of young leaves after 3 weeks of Fe-deficient hydroponic culture. The Fe concentrations in old leaves with high SPAD values were markedly lower in Fe-deficient poplars, suggesting that poplars may have good translocation capability from old to new leaves. The Zn concentration in new leaves increased in Fe-deficient poplars. The pH of the hydroponic solution decreased in the Fe-deficient culture compared to the Fe-sufficient culture. This finding shows that poplars may be able to adjust the pH of a culture solution to better take up Fe. We also analyzed the expression of Fe homeostasis-related genes in the roots and leaves of Fe-sufficient and Fe-deficient poplars. Our results demonstrate that PtIRT1, PtNAS2, PtFRO2, PtFRO5, and PtFIT were induced in Fe-deficient roots. PtYSL2 and PtNAS4 were induced in Fe-deficient leaves. PtYSL3 was induced in both Fe-deficient leaves and roots. These genes may be involved in the Fe uptake and/or translocation mechanisms in poplars under Fe-deficient conditions. Our results will increase a better understanding of the Fe-deficiency response of poplars and hence improve the breeding of Fe-deficiency-tolerant poplars for improved biomass production, the greening of high pH soils, and combatting global warming.  相似文献   
23.
"Fishy aftertaste" is sometimes perceived in wine consumed with seafood. Iron in wine has been reported to be a key compound that produces fishy aftertaste. However, cost-effective methods to remove iron from wine have not been developed. Here, we describe a cost-effective and safe iron adsorbent consisting of alcohol-treated yeast (ATY) cells based on the observation that nonviable cells adsorbed iron after completion of fermentation. Treatment of cells with more than 40% (v/v) ethanol killed them without compromising their ability to adsorb iron. Drying the ATY cells did not reduce iron adsorption. Use of ATY cells together with phytic acid had a synergistic effect on iron removal. We term this means of removing iron the "ATY-PA" method. Sensory analysis indicated that fishy aftertaste in wine-seafood pairings was not perceived if the wine had been pretreated with both ATY cells and phytic acid.  相似文献   
24.
After screening of 177 disomic addition lines (DALs) of wheat (Triticum aestivum) containing a pair of chromosomes from different alien species, we found that the chromosome 1E addition line of Agropyron elongatum, that is known to be a potential genetic resource for drought and salinity tolerance, showed potential for improvement of bread-making quality of wheat. This was indicated by increased SDS sedimentation, specific sedimentation, mixograph peak time and SE-HPLC analysis of polymeric proteins. This addition line spontaneously gave rise to a substitution line for chromosome 1D in subsequent generations that showed weak dough strength. Analysis of the x-type HMW-glutenin subunit sequence of Ag. elongatum from DAL1E indicated that it closely resembled the x-type sequence of the A and B genomes of wheat, and the y-type was intermediate between x- and y-type HMW-glutenin subunit genes. From these observations, it was inferred that 1E-encoded seed storage proteins have considerable potential for improvement of wheat end-product quality if transferred to specific chromosomes such as 1A of Chinese Spring (CS) wheat, which has a negative overall effect on bread-making quality.  相似文献   
25.
This study involved screening of wild species of wheat in search of functionally useful seed storage proteins for improvement of breadmaking quality of wheat (Triticum aestivum). After screening of 177 disomic addition lines (DALs) of wheat belonging to different wild species, Aegilops searsii DALs were selected and studied in detail. These DALs of Ae. searsii were from chromosome 1Ss to 7Ss in the background of cultivated wheat cv. Chinese Spring (CS). By analyzing these addition lines, genetic loci of actively expressed genes for the high molecular weight glutenin subunits (HMW‐GS) and gliadin were found on the chromosome 1Ss for the first time and have been designated as Glu‐Ss1 and Gli‐Ss1, respectively. Disomic addition line of chromosome 1Ss (DAL1Ss) showed improved dough strength in different generations compared with CS. SDS sedimentation value and specific sedimentation of DAL1Ss were higher than CS. Mixograph peak height and band width were higher, with no difference in mixing peak time from CS. All these factors indicate a positive effect of quantity as well as quality of gluten proteins of Ae. searsii. This was further supported by increased polymer formation in DAL1Ss because the ratio of unextractable polymeric protein to total polymeric protein (UPP/TPP%) of DAL1Ss was significantly higher than CS. Genes for HMW‐GS (major determinant of end‐product quality in wheat) of Ae. searsii were cloned and sequenced from the DAL1Ss. Phylogenetic analysis of deduced amino acid sequences showed that both x and y HMW‐GS were more similar to that of D genome rather than B genome of wheat. Although S genome is structurally more similar to B genome of wheat, functionally it is more similar to the D genome of wheat and possesses good quality HMW‐GS required for improvement of breadmaking quality of wheat.  相似文献   
26.
27.
Formosa landlocked salmon (Oncorhynchus masou formosanus), an endemic, critically endangered subspecies of Cherry salmon (Oncorhynchus masou) complex, is only found in Taiwan. Because the eyed eggs and ungutted carcasses of Pacific salmons (genus Oncorhynchus) are imported for aquaculture and food to Taiwan from overseas every year, the requirement for preventing illegal trade or accidental commercial imports to avoid unwanted fish from contaminating the gene pool of Formosa landlocked salmon and infect them with diseases is critical for the conservation of Formosa landlocked salmon. Traditional morphology‐based species identification is impossible for salmon eggs and larvae that lack clearly defined morphological features. In the present study, the genetic differences among four subspecies (Oncorhynchus masou ishikawae, O. masou subsp., Oncorhynchus masou masou and O. masou formosanus) of Cherry salmon complex were determined from microsatellite DNA and amplified fragment length polymorphism analyses. We successfully generated a genetic marker to aid traditional taxonomy and investigate the integrity of the current taxonomic status among members of Cherry salmon complex. Use of molecular markers, in combination with traditional morphological identification, is a promising tool for identifying four closely related subspecies of Cherry salmon complex.  相似文献   
28.
The object of this study was to determine the details of morphological dynamics of spermatogenesis in Syrian hamsters exposed to both short photoperiod and low ambient temperature. Eight-week-old male hamsters, kept in a long photoperiod (14 h L, 10 h D), were transferred to a short photoperiod (6 h L, 18 h D) and kept there for 13 weeks to induce testicular regression. Some hamsters were then transferred from the room at 23 degrees C to that at 5 degrees C (5 degrees C group). Remaining hamsters were continuously kept at 23 degrees C (23 degrees C group). Thereafter, the morphology was examined. As a result, it took only 8 weeks until spermatogenesis recovered in the 23 degrees C group. However, it was not until 20 weeks that spermatogenesis was recognized in the 5 degrees C group. As the regulation of seasonal testicular activity is characterized by coordinated shifts in the relationships among mitosis, meiosis, and apoptosis, the changes in the proliferative and apoptotic activities were examined. Although no significant difference in proliferative activity of spermatogonia between the 5 degrees C and the 23 degrees C groups was confirmed, a notable increase in the rate of apoptosis was observed in the 5 degrees C group. Furthermore, this increase was more salient during the hibernation period. These findings suggest that both cold ambient temperature and hibernation caused the delay of testicular recrudescence and this delay arose from the increase of apoptotic activity but not the change in proliferative activity in spermatogonia in the 5 degrees C group.  相似文献   
29.
[目的]籽粒硬度是重要的小麦品质性状,了解新生疆小麦地方品种籽粒硬度的变异类型和分布,为新疆小麦品质育种提供遗传信息.[方法]利用单籽粒硬度仪(SKCS)和PCR扩增、酶切及DNA测序技术,结合改良的Friabilin提取及电泳分析方法,对105份新疆小麦地方品种的籽粒硬度及Pina和Pint等位基因进行研究.[结果]新疆小麦地方品种以硬质类型为主,平均硬度值为63.5.新疆小麦地方品种Puroindoline基因共有9种突变型,分别是Pina-D1a/Pinb-D1a,Pina-D1a/Pinb-Dlb,Pina-D1a/Pint-D1p,Pina-D1k ()/,Pina-D1l/Pinb-D1a,Pina-D1r/Pinb-D1a,Pina-D1a/Pinb-D1ab,Pina-D1a/Pint-Dlac和Pina-D1b/Pinb-D1p,其中Pina-D1 r/Pinb-D1a为新发现的突变型.新疆小麦地方品种Puroindoline基因型以Pina-D1a/Pinb-D1p为主导类型,共有62份,占59.1;;其Pina-D1k()/和Pina-D1 a/Pint-D1ab两种突变型与其地理来源和生态型密切相关,主要分布在南疆冬小麦中.Pina-D1a/Pinb-D1a(野生型)的硬度值显著低于突变型,Pina-Dlk()/的硬度值最高,但Pins-D1k ()/ ,Pina-D1a/Pinb-D1p和Pina-D1a/Pinb-D1ab的硬度值差异不显著.[结论]新疆小麦地方品种籽粒硬度及其Puroindoline等位变异和分布信息能为新疆小麦品质改良和引种提供理论依据.  相似文献   
30.
1. To investigate the effect of replacing maize with whole-grain paddy rice (WPR) in broiler chicken diets, with or without enzyme addition, on growth performance and histological structures of the intestinal villi, 14-d-old Marshall Chunky male chicks were divided into 4 groups with 4 replicates of 4 chicks each. The experimental diets containing different concentrations of WPR were as follows: (1) 0 g/kg (Control); (2) 141.5 g/kg, grower, and 125.0 g/kg, finisher (25WPR); (3) 283.0 g/kg, grower, and 250.0 g/kg, finisher (50WPR); (4) 283.0 g/kg, grower, and 250.0 g/kg, finisher, and enzyme supplementation (50WPR + enzyme). All diets were formulated to be isocaloric and isonitrogenous and provided ad libitum for 35 d.

2. There were no differences among the diets on the growth performance and digestive organ size.

3. The villus height and cell mitosis number of all intestinal segments did not change in any treatment. The ileal villus area, duodenal cell area, duodenal and jejunal goblet cell number in the 50WPR group increased significantly relative to the control but not when enzyme was included.

4. In the scanning electron microscope results, all experimental groups showed clear protuberant cells and cell clusters on the villus apical surface of the duodenum. In the jejunum, cell clusters and areas having cells with no microvilli were frequently found in both the 50WPR and 50WPR + enzyme groups.

5. In conclusion, broilers fed on diets replacing maize with WPR showed hypertrophied villi of duodenum and ileum and epithelial cells in duodenum and jejunum, especially in the 50WPR group, without negatively affecting growth performance. These findings suggest that WPR can replace maize up to a level of 50% (283.0 g/kg, starter, and 250.0 g/kg, finisher) in broiler diets without enzyme supplementation. However, further studies are needed to improve our knowledge of the influence of WPR on higher numbers of birds.  相似文献   

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