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391.
The reduction of extra subcutaneous, intermuscular and abdominal fat is important to increase the carcass lean percentage of pigs. Image analyses of fat area ratios were effective for estimation of separated fat in pig carcasses. Serum concentrations of leptin are useful as physiological predictors of fat accumulation in pigs. The objectives of the present study were to perform a quantitative trait locus (QTL) analysis for fat area ratios and serum leptin concentrations in a Duroc purebred population. Pigs (n = 226 to 538) were measured for fat area ratios of carcass cross‐sections at the fifth to sixth thoracic vertebrae, half body length and last thoracic vertebra using an image analysis system, and serum leptin concentration. In total, animals were genotyped for 129 markers and used for QTL analysis. For fat area ratios, four significant and 12 suggestive QTLs were detected on chromosomes 1, 6, 7, 8, 9, 12 and 13. Significant QTLs were detected on the same region of chromosome 6, which was located near a leptin receptor gene. For serum leptin concentrations, two significant and two suggestive QTLs were detected on chromosomes 6, 9, and 16, and the QTLs on chromosome 6 were also in the same region for fat area ratios.  相似文献   
392.
Fibroblast growth factor 4 (FGF4) is considered as a crucial gene for the proper development of bovine embryos. However, the complete nucleotide sequences of the structural genes encoding FGF4 in identified breeds are still unknown. In the present study, direct sequencing of PCR products derived from genomic DNA samples obtained from three Japanese Black, two Japanese Shorthorn and three Holstein cattle, revealed that the nucleotide sequences of the structural gene encoding FGF4 matched completely among these eight cattle. On the other hand, differences in the nucleotide sequences, leading to substitutions, insertions or deletions of amino acid residues were detected when compared with the already reported sequence from unidentified breeds. We cannot rule out a possibility that the structural gene elucidated in the present study is widely distributed in cattle. To the best of our knowledge, this is the first determination of the complete nucleotide sequence of the structural gene encoding bovine FGF4 in identified breeds.  相似文献   
393.
The present study clarified the effects of winter barley as a cover crop on the weed vegetation, expressed as a multiplied dominance ratio (MDR), and emergence of summer annual weeds in a no-tillage soybean system. A 3 year field study with treatments consisting of six systems was conducted: no-tillage single cropping, no-tillage cropping following winter barley and tillage single cropping, respectively with and without herbicide application. The MDR of perennial weeds increased annually in the no-tillage fields in spring, but summer annual weeds were abundant in all fields, including the no-tillage fields in summer. Grasses, for example Digitaria ciliaris (Retz.) Koeler, were especially abundant in the no-tillage fields. The MDR of summer annual weeds, especially grasses in the barley and soybean fields, were much lower than for the no-tillage single soybean fields. Densities of D. ciliaris and Echinochloa crus-galli (L.) Beauv. var. crus-galli in the no-tillage single soybean fields were much greater than in the tilled fields, with few exceptions. In contrast, broad-leaved weeds emerged more in tilled fields than in the no-tillage fields. Winter barley suppressed emergence of summer annual weeds, especially during the first 3 years. The MDR for grasses in summer showed a good correlation with the frequency of emergence for grasses every year. These results showed that the increase in the volume of grasses in summer resulted mainly from an increase in the frequency of emergence, and that the suppression of grasses by winter barley resulted mainly from suppression of the emergence frequency. Soybean yields were higher in the barley and soybean fields for the first 2 years.  相似文献   
394.
 In June 1996, a leaf spot disease widely occurred in Japanese persimmon (Diospyros kaki) orchards in Tottori Prefecture, Japan. The main diagnostic symptom was ring spot on the leaves and calyxes of young fruits; in severe cases, lesions developed on more than half of the area of the leaf, resulting in early defoliation. Based on morphological and pathological studies of the isolated fungi, it was shown that Pestalotiopsis longiseta, P. glandicola, P. acaciae, and P. crassiuscula were responsible for the diseases. These fungi, except P. longiseta, were found to be new pathogens of the disease. Received: May 20, 2002 / Accepted: July 25, 2002  相似文献   
395.
A leaf spot disease on sweet basil (Ocimum basilicum L.) was observed in Chiba Prefecture in 1997. The lesions were amphigenous, circular to irregular, hygrophanous, dark brown. Stromata were amphigenous, composed of a few brown cells. Conidia with a thickened truncate base, filiform to cylindrical, hyaline, were produced from conidiophores with thickened conidial scars. These morphological characteristics agreed with those of Cercospora guatemalensis Mueller et Chupp. This species was new to Japan. The symptoms appeared 10 days after inoculation and the inoculated fungus was re-isolated. Artificial sporulation and detection from commercial seeds were not successful. Received 7 May 2001/ Accepted in revised form 7 August 2001  相似文献   
396.
Shoot blight and leaf spots were found on highbush blueberry trees in Tsukuba, Ibaraki, in 1999. The causal fungus was identified morphologically as Colletotrichum acutatum Simmonds ex Simmonds. This is the first report of blueberry anthracnose caused by C. acutatum in Japan. Received 16 November 2001/ Accepted in revised form 22 March 2002  相似文献   
397.
Brown leaf spot of Lantana camara L. and L. montevidensis Briq. caused by Pseudocercospora guianensis (Stevens et Solheim) Deighton was found in Shizuoka, Chiba, Kagoshima and Okinawa Prefectures. Pathogenicity of isolates from the leaf spots was examined, and a taxonomic study as well as identification of the causal fungus was carried out. Similar leaf spots appeared on 7 to 25 days after inoculation with the isolates on Lantana spp., and the same fungus was re-isolated from the inoculated leaves. Two hitherto known Pseudocercospora species on Lantana, P. guianensis and P. formosana, were considered to be variations within one species, and we identified the causal fungus as P. guianensis due to priority. Received 25 September 2000/ Accepted in revised form 20 May 2001  相似文献   
398.
The sterol 14α-demethylation inhibitors 1-(4-substituted phenoxymethyl)-2, 2-dimethylpropyl imidazole-1-carboxylates and their corresponding thiocarboxylates were optimized for maximum in-vitro activity against Botrytis cinerea Pers. ex Fr. in terms of the lipophilic parameter π. The activity of both carboxylates and thiocarboxylates was strongly related with π and predicted to be maximum at π 1.38 and 0.72 respectively. However, the preventive efficacy of the carboxylates against B. cinerea on Solanum melongena L. grown in a greenhouse did not correlate with the parameter. Despite the unfavourable lower lipophilicity, compounds with p-alkoxy substituents were superior to those with any other substituent. Moreover, the p-methoxy-substituted thiocarboxylate 46 was much less effective in greenhouse tests than the corresponding carboxylate 15, despite their equivalent in-vitro activity. To clarify these discrepancies, hydrolytic and photolytic stabilities of several representative compounds including 15 and 46 were investigated. The carboxylates examined were much more labile to hydrolysis than the thiocarboxylate 46; however, the four thiocarboxylates studied were less stable to light than the carboxylates. Consequently, the above discrepancies were attributable mainly to the superior stability of the carboxylates to photolysis as compared to the thiocarboxylates.  相似文献   
399.
Barley ( Hordeum vulgare L.) nicotianamine synthase gene ( HvNAS1 ) expression in barley is strongly induced by Fe deficiency in the roots and rice ( Oryza sativa L.) nicotianamine synthase gene ( OsNAS1 ) expression in rice is induced by Fe deficiency both in the roots and in the shoots. In dicots, NAS genes are not strongly induced by Fe deficiency, and they function to maintain Fe homeostasis. Rice OsNAS1promoter::GUS or barley HvNAS1promoter::GUS was introduced into tobacco ( Nicotiana tabacum L.) and tissue specificities and systemic regulation of their expression were compared. A split-root experiment revealed that the HvNAS1 promoter exhibited functions similar to those of Fe-acquisition-related genes in tobacco roots, suggesting that this promoter responded to certain Fe-deficiency systemic signals and to the Fe concentration in the rhizosphere. The HvNAS1 promoter might harbor a type of universal system of gene expression for Fe acquisition. However, the OsNAS1 promoter did not respond to local application of Fe to the roots and induced GUS activities in mature leaves in response to Fe deficiency. This promoter might possess numerous types of cis -acting sequences that are involved in Fe metabolism.  相似文献   
400.
Paddy and Water Environment - This study aims to investigate a possibility of quantitative assessment of the relationship between return flow from paddy fields and river regime by using hydrogen-...  相似文献   
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