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11.
Ethnobotanical survey was conducted in 101 randomly selected home gardens of Phong My commune, central Vietnam, situated in the buffer-zone of Natural Reserve. Data were collected through semi-structured questionnaires and direct observation. Sixty-seven species belonging to 35 families were identified to be used for various purposes. For each species the botanical and vernacular names, plant parts used and main purposes of use are given. The major use categories reported for plant species were food (86%), medicine (32%) and firewood (32%), however, seventy-seven percent of all inventoried plants have multiple uses. The species Artocarpus heterophyllus Lam., Citrus grandis Osbeck, Citrus reticulata Blanco, Ipomoea batatas (L.) Lam. and Musa spp. were identified as the main sources of plant foods consumed within the households. Statistical analyses indicated by Shannon-Wiener and Margalef indices have shown that local species diversity and richness is affected by home garden size. On the contrary, no relationship between diversity and home garden age was found. On the basis of a cluster analysis of plant species diversity, five home garden types were differentiated. In comparison to previously reported studies on tropical home gardens, the diversity in Phong My is lower, probably due to market-oriented strategy. Nevertheless, based on the results achieved, we can conclude that useful plants cultivated in local home gardens provide valuable foods complementing daily diet and subsequently contributing to socioeconomic status of the households.  相似文献   
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Abstract

Due to continuous single nitrogen fertilization, we hypothesized a built-up deficiency of micronutrients in crops that would limit plant growth and crop quality. In 2-year field experiments using urea-N fertilized grain maize (Zea mays L.), hybrid KWS 2376 at 0, 120 and 240 kg N ha?1 crop uptake of Zn, Mn, Cu and Fe was studied at DC 32, DC 61 and in the grain harvested. Micronutrient contents at DC 32 stage – 1st node (aboveground phytomass) and DC 61 – flowering (ear leaf) were all at levels indicative of adequate micronutrient supply to the crop. At both sampling occasions the Fe:Zn and Fe:Mn ratios were adequate implying that Fe did not inhibit the uptake of Zn and Mn. The application of nitrogen increased the Fe content at the 1st sampling in both years; in the second year the same was also the case for the Zn content. Nitrogen nutrition increased the contents of Mn and Fe at the 2nd sampling only in year 2; in the other treatments no changes were observed in the micronutrient contents. Micronutrient correlations in the grain were discovered between Zn and Mn contents and between Fe and Mn contents. In the second year the highest N-rate significantly increased the Fe and Zn content of the grain compared with the lower rates of nitrogen fertilization. Grain yields were not affected by the rate of nitrogen and ranged between 13.65 and 14.34 t ha?1 (1st year) and between 13.68 and 14.18 t ha?1 (2nd year). Nitrogen fertilization did not reduce the content of micronutrients in the plant or grain of maize. It is evident that the continuous single use of N fertilization so far has not resulted in a micronutrient deficiency of the plants limiting the nutrient density of the grain or reducing its quality.  相似文献   
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The histochemical method of Jaspar-Versali et al. (1982) was modified for the detection of enzyme activity in homogenate of soil mites.  相似文献   
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Summary Natural enemies of Euproctis chrysorrhoea in orchards in Yugoslavia During an outbreak ofEuproctis chrysorrhoea in orchards near Kosovo, Yugoslavia, several parasites (Larvaevoridae and Ichneumonidae especiallyApanteles), predators (Coleoptera of the generaCantharis andMalachius) as well as a protozoic disease were observed attacking the pest. The disease agent was recognized to be a new species:Nosema kovaevii sp. n. (Microsporidia). The cycle of development of the new species is described. Opposite to related species the spores ofN. kovaevii show a great variety in length.  相似文献   
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Larssoniella duplicati n.sp. infects the midgut muscularis, the Malpighian tubules, and the ovaries of adult Ips duplicatus (Sahlb.) in the Czech Republic. The microsporidian attacks up to 50% of the population. Oval spores of two sizes, 3–3.5×1.5–2 and 2–2.5×1.5 μm have the polar filament coiled in 6/7 coils, representing primary and environmental spores, respectively. In early sporogony the young spores produce long electron dense threads and tubules of secretions, which remain fixed around the spore and avoid their free release during dissection of infected hosts. The microsporidian was not found in associated bark beetles such as Ips typographus (L.), or I. amitinus (Eichh.) and others.  相似文献   
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We demonstrate, using height data from a clonal trial, how the genomic best linear unbiased predictor method (GBLUP) is ideal for determining future breeding potential in situations (either in plantations or wild stands) where high mortality due to biotic or abiotic factors has occurred. The method is effective because it does not require the development of structured pedigree or classical progeny testing, rather it uses DNA fingerprinting to determine the genealogical relationship among individuals. The resulting genetic network is known as the realized relationship matrix, which in turn is used in classical quantitative genetics analyses to determine the genetic worth of all fingerprinted individuals. Selection of desirable individuals among the surviving population is aimed at maximizing genetic diversity even when the original genetic source is unknown. This is accomplished by determining the number of founder genome equivalents which can be used to estimate the inbreeding effective population size. During the selection phase, genetic diversity can be balanced against genetic gain so that diversity is maximized while gain for any particular attribute is optimized.  相似文献   
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A 15-month-old dachshund was presented for examination because of a cough. Thoracic radiographs revealed the presence of a mass in the upper mediastinum. A diagnosis of γδ T-cell lymphoma was made by biopsy and flow cytometry analysis. The dog was treated with chemotherapy and remains asymptomatic after 24 months.  相似文献   
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