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1.
The genetic characteristics of the dominant genotypes of Phytophthora infestans in Japan (US-1, JP-1, Japanese A1-A, A1-B) were compared. Differences were evident in the peptidase genotype, amplified fragment length polymorphism, and RG57 DNA fingerprints. Almost all of the fingerprint bands for the Japanese genotype A1-B were also present in JP-1 and Japanese A1-A, and few bands were unique to Japanese A1-B. These results suggest that the Japanese A1-B genotype was generated from sexual reproduction involving Japanese A1-A and JP-1 or related genotypes.  相似文献   
2.
Microsatellite markers were tested to rapidly discriminate five Japanese genotypes (US-1, JP-1, JP-2, JP-3, and JP-4) of Phytophthora infestans. Collected from 1958 to 2007, 111 isolates of Japanese P. infestans were examined using a fluorescent-labeled primer and capillary electrophoresis. Microsatellite marker Pi26 generated specific products for each genotype without any differences in terms of isolation area or year for a particular genotype. The Pi26 marker is a powerful tool for obtaining information on the structure of Japanese populations of P. infestans.  相似文献   
3.
The sexual preferences of Japanese isolates of Phytophthora infestans were determined by mating on agar, in broth, or in plants. The influence of their sexual preference was confirmed in the host tissues. Three wild-type isolates and a -glucuronidase (GUS) transformant were co-cultured to identify the origin of antheridia and oogonia. Japanese A1 isolate had a unique sexual preference compared with foreign isolates. It produced self-fertile oospores with about 40% of total gametangia but tended to form antheridia on V-8 agar medium. In addition, oospores were formed in plants, but their sexual preference could not be reflected in vitro.  相似文献   
4.
Anguilla luzonensis and A. huangi were each described in 2009 using eels obtained from northern Luzon Island. We examined the taxonomic status of these two groups of eels using morphological and molecular genetic characters. There were no significant differences in two vertebrae counts between eels of A. luzonensis and A. huangi. Mitochondrial 16S ribosomal RNA and cytochrome b genes sequences were obtained and compared among 28 specimens of A. luzonensis, the holotypes of A. luzonensis and A. huangi, and one specimen of the other 15 anguillid species. The specimens of A. luzonensis exhibited almost identical sequences, including the holotype, with only a few site differences, and the genetic difference between the holotypes of A. luzonensis and A. huangi was within the range of differences of specimens of A. luzonensis. The other anguillid species were genetically very different from A. luzonensis and A. huangi, although A. interioris is a closely related species. It is clear that A. luzonensis and A. huangi are the same species, and according to the principle of priority in zoological nomenclature, A. luzonensis Watanabe, Aoyama, and Tsukamoto, 2009 is the valid species name, and A. huangi Teng, Lin, and Tzeng, 2009 is a junior synonym of A. luzonensis.  相似文献   
5.
To effectively utilize total mixed ration (TMR) prepared with locally available feed resources, we studied the nutritional value and milk production in Jersey dairy cattle fed a local general diet (LGD) and fermented TMR in Mozambique. Ten head of Jersey dairy cattle with 337 ± 19.8 kg body weight, aged 3–4 years in mid location were used in this study. The LGD diet was designed following the general feeding method of local smallholding farms; it contained native grass, Napier grass, wheat bran, and mineral–vitamin mix. Fermented TMR was prepared using Napier grass, corn bran, wheat bran, formula feed, and mineral–vitamin mix. Fermented TMR was preserved as good quality, with a relatively low pH and high lactic acid content. Compared to LGD, fermented TMR significantly improved the dry matter intake and digestibility in dairy cattle. Milk yield was significantly higher in dairy cattle fed with TMR than in those fed with LGD, by 3.75 L/d; milk quality was not significantly different between treatments. The results confirmed that LGD had a low dry matter intake and milk yield, and fermented TMR prepared with local feed resources can attain good quality and improve milk yield in dairy cattle in Mozambique.  相似文献   
6.
The association of lactic acid bacteria with mucosal surfaces plays important roles in the beneficial effects of these bacteria on human health, such as colonization of the gastrointestinal tract for pathogen antagonism. Previously, we found that the adhesion of Lactococcus lactis 7‐1 to porcine gastric mucin was higher with fructose than with lactose, galactose or xylose as the carbon source. In this study, we examined the effect of growth conditions on the adhesion of strain 7‐1 grown on fructose. Medium components affect the adhesion: the adhesion of strain 7‐1 grown with sodium acetate was higher than that without it. The enhancement of adhesion by sodium acetate was not observed under aerobic conditions. Cellular properties grown with or without sodium acetate were characterized: strain 7‐1 grown with sodium acetate had similar sugar contents, and different fatty acid composition to those grown without it. Strain 7‐1 grown with sodium acetate showed significantly lower cell yield and significantly higher hydrophobicity than those grown without it, which is associated with higher adhesion. Fructose and sodium acetate are frequently used in the food industry; this study may reveal a simple way to enhance the adhesion of lactic acid bacteria by growing them with these substances.  相似文献   
7.
8.
Several attempts have been undertaken to exploit the resistance to late blight [Phytophthora infestans (Mont.) de Bary] of the Mexican diploid Solanum pinnatisectum Dunal (2n = 2x = 24). However, sexual hybridization between S. pinnatisectum and cultivated potatoes is almost impossible because of strict reproductive barriers. In this study, we first induced chromosome doubling of S. pinnatisectum for matching of the species-specific endosperm balance number (EBN), which is a genetic phenomenon responsible for normal endosperm development. We pollinated 4x (2EBN) S. pinnatisectum flowers with pollen from 2x (2EBN) clones carrying the S locus inhibitor gene (Sli), which originally was identified as an inhibitor of S-locus-controlled self-incompatibility in pollen of diploid potatoes. Nine putative hybrid plants were obtained from 613 pollinations, of which two plants were characterized. Both individuals were triploid hybrids with extreme resistance to P. infestans derived from S. pinnatisectum and showed an acceptable level of female fertility for backcrossing. Thus, utilization of the Sli gene, combined with chromosome-doubling for matching of the EBN, is proposed as a technique to overcome barriers to interspecific hybridization between Mexican 2x (1EBN) Solanum species and cultivated diploid potatoes.  相似文献   
9.
High grazing density has given rise to concerns about grassland degradation in periurban areas in Mongolia. Moreover, whether livestock can increase without harming the vegetation in these areas in Mongolia and what types of policy measures should be implemented is not documented. As such, this study develops an integrated simulation model of grassland biomass, animal growth, and livestock management for a forest-steppe area in northern Mongolia and conducts a simulation on long-term changes. The simulations show that, under current conditions, the number of animals will continue to increase, while the grassland biomass will decrease. Cooperative grassland management would lead to an increase in grassland biomass and higher incomes for herders. Furthermore, herders’ population changes would have a significant impact on animal density adjustments, while the effects of conventional economic measures, such as a tax on animals, would be limited if all other conditions remain constant. Consequently, the synergistic effects of herder population changes and cooperative management can contribute toward maintaining the herders’ income while preserving the grassland ecosystem.  相似文献   
10.
In August 2010, bacterial soft rot was found on root chicory (Cichorium intybus var. sativum) in Hokkaido, Japan. Severely infected plants in fields were discolored, had wilted foliage, and black necrosis of petioles near the crown. Wilted leaves subsequently collapsed and died, forming a dry, brown or black rosette. The root and crown became partially or wholly soft-rotted. Slimy masses on infected areas of roots, turned dark brown or black. Gram-negative, rod-shaped, peritrichously flagellated, facultatively anaerobic bacteria were exclusively isolated from rotted roots, and typical symptoms were reproduced after inoculation with the strains. The bacteria were identified as Dickeya dianthicola, Pectobacterium carotovorum subsp. carotovorum, and Pectobacterium carotovorum subsp. odoriferum based on further bacteriological characterization and the sequence analysis of the malate dehydrogenase gene and 16S rRNA gene. These bacteria should be included with the previously reported Dickeya (=Erwinia) chrysanthemi in Saitama Prefecture, Japan, as causal pathogens of bacterial wilt of chicory.  相似文献   
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