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111.
112.
Chandra Prasad Risal Tadashi Yokoyama Naoko Ohkama-Ohtsu Salem Djedidi Hitoshi Sekimoto 《Systematic and applied microbiology》2010
Soybean-nodulating bradyrhizobia are genetically diverse and are classified into different species. In this study, the genetic diversity of native soybean bradyrhizobia isolated from different topographical regions along the southern slopes of the Himalayan Mountains in Nepal was explored. Soil samples were collected from three different topographical regions with contrasting climates. A local soybean cultivar, Cobb, was used as a trap plant to isolate bradyrhizobia. A total of 24 isolates selected on the basis of their colony morphology were genetically characterized. For each isolate, the full nucleotide sequence of the 16S rRNA gene and ITS region, and partial sequences of the nifD and nodD1 genes were determined. Two lineages were evident in the conserved gene phylogeny; one representing Bradyrhizobium elkanii (71% of isolates), and the other representing Bradyrhizobium japonicum (21%) and Bradyrhizobium yuanmingense (8%). Phylogenetic analyses revealed three novel lineages in the Bradyrhizobium elkanii clade, indicating high levels of genetic diversity among Bradyrhizobium isolates in Nepal. B. japonicum and B. yuanmingense strains were distributed in areas from 2420 to 2660 m above sea level (asl), which were mountain regions with a temperate climate. The B. elkanii clade was distributed in two regions; hill regions ranging from 1512 to 1935 m asl, and mountain regions ranging from 2420 to 2660 m asl. Ten multi-locus genotypes were detected; seven among B. elkanii, two among B. japonicum, and one among B. yuanmingense-related isolates. The results indicated that there was higher species-level diversity of Bradyrhizobium in the temperate region than in the sub-tropical region along the southern slopes of the Himalayan Mountains in Nepal. 相似文献
113.
Wild edible plants form an important constituent of traditional diets in the Himalaya. In the Sikkim Himalaya a total of 190
species have been screened as edible species out of which nearly 47 species come to the market. The present paper deals with
nutritive values of 27 most commonly consumed wild edible plants in the Sikkim Himalaya. Of 27 plant species that were analyzed
for their nutritive values, 22 were edible for their fruits and five for leaves/shoots. Among different plant parts, generally
higher nutrient concentration was recorded for leaves, followed by new shoots and fruits. For different species the crude
fiber content ranged between 2.15–39.90%, and the total soluble salts between 4.66–21.00%, and the vitamin C content from
6–286 mg/100 g. The fat content was determined high in the fruits ofCastanopsis hystrix, Machilus edulis, andCinnamomum species, while the protein content was highest inHippophae rhamnoides, Cucumis melo, andEleagnus latifolia. The total carbohydrate content ranged from 32–88% in the fruits of various wild edibles, the reducing sugar from 1.25–12.42%,
total sugar from 2.10–25.09%, the lignin content varied from 9.05–39.51%, the hemicellulose between 25.63–55.71% and cellulose
content varied from 9.57–33.19% in different species. Among the various macronutrients estimated in the plant samples of different
wild edible species, nitrogen was present in highest quantity, followed by potassium, calcium, magnesium, phosphorus, and
sodium. Micronutrients, such as iron, zinc, magnesium, and copper contents were analyzed in different plant parts of various
wild edible species. The iron content was higher in leaves and new shoots. The nutritive values of certain wild edible species
determined in this study are comparable with various commercial fruits. It is suggested that a few wild edible species need
to be grown for commercial cultivation and adopted in the traditional agroforestry systems, which will lead to reduced pressure
on them in natural forest stands as well as producing economic benefits for poor farmers. 相似文献
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116.
《Journal of bryology》2013,35(2):339-346
AbstractType material is studied for six names of southern hemisphere Racomitria, viz. R. dustro-georgicum Par., R. amoenum (Broth.) Par., R. substenocladum Card., R. skottsbergii Card. et Broth., R. substenocladum fo. *nigrescens Card. et Broth., and R. austro-georgicum var. kranckii Riov. They are all placed as synonyms of R. sudeticum (Funck) Bruch et Schimp., which accordingly is bipolar. Racomitrium austro-sudeticum Broth. in Herz. belongs to the genus Grimmia. 相似文献
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118.
Hirokazu Tsukaya Jun Yokoyama Hiroshi Ikeda Haruko Kuroiwa Tsuneyoshi Kuroiwa Kunio Iwatsuki 《Journal of plant research》1997,110(1):15-23
Arabidopsis himalaica (Edgeworth) O.E. Schulz, a poorly characterized species typical of HimalayanArabidopsis, was analyzed in terms of its morphology, physiology, chromosome number and molecular genetics, in comparison withA. thaliana which is the standard species in the genusArabidopsis. From view point of developmental genetics, several features which are specific toA. himalaica seem not to be derived by single-gene mutations inA. thaliana. Phylogenetic analyses based onrbcL sequences suggested that genusArabidopsis is not monophyletic. The detailed characterization ofA. himalaica should provide clues to understand the trait of evolution of particular features of Himalayan species ofArabidopsis and their genetic basis. 相似文献
119.
Livestock in high altitudes of Nepal and elsewhere, frequently and freely, use potential habitat of native wildlife for foraging. Such intrusion of ecologically similar domestic species is supposed to negatively impact the resident wildlife via ‘perceived’ and/or ‘real’ competitive interactions. Hence, assessment of dietary composition and overlap between herbivores is crucial to gain insight into the potential impacts via resource exploitation by foraging livestock. Also, evaluation of dietary composition of resident wildlife across seasons is important to decipher their seasonal resource needs. Within this context, microhistological technique, that makes use of fecal pellet for identification of plant species through comparison with reference slides of plant materials in the area, was used to assess dietary composition, breadth, and overlap between seasonally sympatric Himalayan musk deer and livestock in Nepal Himalaya. Musk deer and livestock were found to have significantly different dietary consumption and that partition was contributed by different species; meaning different plant species were associated to the diets of these two groups. Of notable, however, was a considerable ‘number’ of species (i.e., species richness) shared in diets by musk deer and livestock raising a concern of unchecked number of livestock with a potential to exploit and reduce the availability of shared plant species with musk deer. Also, seasonal dietary composition of musk deer significantly varied, with increased dietary breadth in winter, suggesting a potential for intraspecific competition for forage in winter because of limited availability of resources mediated by retarded growth and harsh conditions. 相似文献
120.
The White-Winged Wood duck (Asarcornis scutulata) is an endangered forest wetland bird currently on the verge of extinction due to an array of anthropogenic pressures. It has been reported that global climate change could affect the distribution of many bird species globally. Therefore, an understanding the potential distribution of the White-Winged Wood duck in future climate scenarios could facilitate the creation of immediate conservation plans and the mitigation of subsequent threats. This is the first ever study on the distribution of White-Winged Wood Duck (WWWD) where Representative Concentration Pathway (RCP) 8.5 scenario was used to forecast the distribution of the WWWD in the Indian Eastern Himalayan region in the 2050s and 2070s. The study revealed that 1.87 % of the total area of IEH has the high potential distribution of WWWD. The state of Assam alone includes 1.68 % of the highly potential habitat in the region. It was predicted that 436.61 km2 of highly potential habitat would be lost by 2070. Changes in the annual temperature range, precipitation in the wettest months (June to September), and precipitation decrease in the warmest quarter (October to December) would result in the loss of highly potential habitats. Under the influence of climate change, the habitat of WWWD in the eastern part of the region is likely to shift towards the western part. It was found that there will be a decline in potential habitat in the Indian states of Arunachal Pradesh, Assam, Nagaland, and Tripura located in the IEH under future climate scenarios. The potential of areas located at the Bhutan and Assam border would increase for supporting WWWD as this species' requires the average annual precipitation about 1000–1200 mm. However, the simultaneous anthropogenic activity would further destroy potential habitats in the future. The current study has provided baseline data on the potential distribution of WWWD in the IEH region for immediate conservation management plans. 相似文献