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71.
In this paper, reliable data and information as an important basis for integrated water resources management (IWRM) is discussed. Such data are especially important in transboundary water bodies, as they can represent a common and transparent knowledge-base that all concerned parties can trust and utilise in the management process. The transboundary Lake Macro Prespa (West Balkan) is used as a case study. The lake is rich in biodiversity but threatened by increased eutrophication. The main focus of the monitoring (2007–2008) was therefore on nutrients and chlorophyll a, as well as oxygen levels, transparency and temperature. The results of the monitoring were used in consultations with water managers and other stakeholders, and the study demonstrated how such data could represent a common and neutral point of departure for discussions across borders on integrated lake management. However, the paper also shows that monitoring may result in inadequate or even erroneous information, thus pointing to the importance of understanding all phases of the practical implementation of harmonised monitoring. The main challenges of the harmonised monitoring included different laboratory methods and performances, as well as a number of practical issues related to logistics and communications across borders. A less ambitious programme during the first year of monitoring (2007) might have saved funds and resulted in more harmonised and reliable data this year. However, in 2008 the project succeeded in producing a set of harmonised data, amongst others by using one common and accredited laboratory for stations in both countries. This paper therefore also presents new monitoring data from this unique large lake, of which there are relatively few published studies. The results of the monitoring give reasons for concern. The eutrophication of the lake seems to be increasing, and this calls for improved integrated management in order to reduce nutrient levels and improve the environmental status.  相似文献   
72.
Okra production in the tropics is threatened by attack of insect-pests, fruit and shoot borer (FSB), jassid and whitefly causing severe loss in marketable yield particularly in the Gangetic plains of eastern India. No developed varieties/hybrids are free from attack of these pests. However, improved lines of okra have potential to broaden the genetic variability may improve resistance to these pests. Therefore, the population dynamics of these pests were recorded from 24 advance breeding lines/varieties of okra during peak infestation period over two consecutive years. Morphological leaf traits and biochemical parameters were assessed as potential mediators of resistance. The population of these pests reached above economic threshold levels during the month of September. Significant genotypic differences in terms of infestation of these pests were observed. Negatively correlated physico-chemical characters might be considered as important indices for selection of genotype tolerant to these pests. As indicated by the low infestations, the tolerance of BCO-1 to FSB, whitefly and that of Arka Anamika to jassid is based on both antixenotic properties of the genotypes. The donor parents BCO-1 and Arka Anamika should, therefore, be introduced into okra breeding programs to enhance tolerance against these pests.  相似文献   
73.
Lime-induced changes of biogeochemical cycling bacteria were examined using doses of 25, 50, 100, 200, 500, 1000 and 2000 kg ha–1 in the first part, and post-lime inorganic and organic fertilization in the second part of the experiment. Heterotrophic, ammonifying, denitrifying, cellulose decomposing and phosphate solublizing bacteria were drastically reduced by 30–90% in 1000 kg ha 21and 51D91% in 2000 kg ha–1. Density differences were minor in the remaining test doses for all groups of bacteria except for the dinitrifiers which were reduced in 500 kg ha–1 by 90% over the control. Similarly, reduced rates of ammonification, nitrification and denitrification were dose-dependent. Inorganic fertilization following lime application of 2000 kg ha–1 resulted in no marked increment of the counts of bacteria and activity processes, whereas organic manuring increased the density (50–200%) and the activities (212–292%) as well. Lime-induced changes of bacterial population and activities were explained as a result of high pH stress as well as a major shift in the CO2-HCO3-CO3 equilibrium system. Increase of major nutrients in the post-lime organic treatment was significantly higher than that of inorganic fertilization resulting in favourable N/P ratio and water quality conducive to fish farming after 45 days of liming.  相似文献   
74.
Glycogen content and metabolic enzyme activities viz. lactate dehydrogenase (LDH), malate dehydrogenase (MDH), aspartate amino transferase (AST) and alanine amino transferase (ALT) in Indian major carps, Labeo rohita, Catla catla and Cirrhinus mrigala, were investigated after a 6 h transportation trial to compare the species‐specific variation and the effect of increased packing density on the metabolism. Fish (45±5 mm, 0.5±0.1 g) were packed in three densities (100, 150 and 200 L?1) for the experiment, and 12 specimens of each species were randomly sampled from all the treatments at the end of transportation. The glycogen content of L. rohita ingerlings decreased significantly (P<0.05) with increasing packing density. The activities of enzymes LDH, MDH, AST and ALT showed a rising trend with increasing packing density in all the three species. Species‐specific differences were observed in various tested parameters at the lowest packing density (100 fry L?1). Alanine amino transferase and LDH activities were significantly (P<0.05) lower in C. mrigala as compared with the other two species. However, glycogen reserves and MDH activity were not significantly different (P>0.05) among the species. The present study reveals that the optimum packing density for Indian major carp fry (100 fry L?1) for transportation up to 6 h and metabolic regimes are species specific during transportation.  相似文献   
75.
1. The present study was conducted to estimate genetic relatedness among Nicobari fowls (Brown, Black and White) and an exotic bird (White Leghorn) using random amplified polymorphic DNA (RAPD) polymorphism. 2. A total of 25 decamer primers were screened among all the breeds of which 24 primers amplified the genomic DNA, generating 2000 to 200 bp bands. Ten primers generated reproducible and distinct RAPD profiles and were used for further analysis. 3. A total of 94 bands were amplified and 30 polymorphic bands (32%) were produced. The number of polymorphic loci ranged from 1 to 5 with an average of 3.0. 4. Among the native breeds Brown Nicobari showed higher genetic similarity (0.85) than Black Nicobari (0.80) and White Nicobari fowl (0.82). 5. Brown Nicobari showed high genetic similarity with Black Nicobari (0.87 +/- 0.029); least similarity was between White Nicobari and White Leghorn (0.77 +/- 0.028). 6. The RAPD profile of all Nicobari fowls on amplification with the primers PBG5 and PBA12 showed specific bands of molecular size 1050 and 785 bp, respectively. 7. The native breeds showed the least genetic distance with each other while White Leghorn appeared to be most distant from the native breeds.  相似文献   
76.
In jute (Corchorus olitorius), quantitative trait loci (QTL) analysis was conducted to study the genetics of eight fibre yield traits and two fibre quality traits. For this purpose, we used a mapping population consisting of 120 recombinant inbred lines (RILs) and also used a linkage map consisting of 36 SSR markers that was developed by us earlier (Das et al. 2011). The RIL population was derived from the cross JRO 524 (coarse fibre) × PPO4 (fine fibre) following single seed descent. Using single-locus analysis involving composite interval mapping, a total of 21 QTLs were identified for eight fibre yield traits whereas for fibre quality (fibre fineness), only one QTL was detected. The QTL for fibre fineness explained 8.31–10.56% of the phenotypic variation and was detected in two out of three environments. Using two-locus analysis involving QTLNetwork, as many as 11 M-QTLs were identified for seven fibre yield traits (excluding top diameter) and one M-QTL was identified for fibre fineness which accounted for 4.57% of the phenotypic variation. For six fibre yield traits, we detected 16 E-QTLs involved in nine QQ epistatic interactions. For fibre fineness, four E-QTLs involved in two QQ epistatic interactions and for fibre strength, six E-QTLs involved in three QQ epistatic interactions were identified. Eight out of the 11 M-QTLs observed for the fibre yield traits were also involved in QE interactions; for fibre fineness and fibre strength, no QE interactions were observed.  相似文献   
77.
A general framework of ecosystem hotspots suggests variation in soil metabolic activity can be understood through the relative distribution and intensity of patches of disproportionately high ecosystem process rates. To better understand the causes of soil metabolic spatial variability and the variation in ecosystem hotspots we quantified soil respiration (R) spatial heterogeneity across a network of seven sites spanning a 2,489 m elevation gradient in the Santa Rosa Mountains of Southern California. At each site, soil samples were collected from 0–5 and 5–15 cm soil depths at 2 m intervals along three 100 m transects. Each soil sample was analyzed for organic matter content (SOM) and was incubated at 40% water holding capacity for 20 days. R was measured at days 5 and 20. Strong contrasts were observed between the relationships of soil physical variables and R at scales of individual landscapes and the whole region. Notably, the relationship between SOM and R was positive within individual landscapes and negative across the entire region. Plant canopy microenvironments were associated with elevated SOM and R relative to the interspaces. This microenvironment effect on R was reduced by elevation, incubation interval, and soil depth. Geostatistical analyses conducted individually for each site identified an increasing range of autocorrelation from 2 to 10 m and a decreasing proportion of variation that was included in this range with elevation. These results suggest hotspots increase in size but decrease in intensity with elevation thereby creating a maximum hotspot effect at middle elevations.  相似文献   
78.
1. The objectives of the study were to detect polymorphism in the coding region of the IGF1 gene, explore the expression profile and estimate association with growth traits in indigenous and exotic chickens.

2. A total of 12 haplotypes were found in Cornish, control layer and Aseel breeds of chicken in which the h1 haplotype was most frequent.

3. Nucleotide substitutions among haplotypes were found at 21 positions in the IGF1 gene in which 4 substitutions resulted in non-synonymous mutations in the receptor binding domain of the IGF1 protein.

4. The haplogroup showed a significant effect on body weight at 24 and 42 d of age in the control layer line, body weight at 42 d and daily weight gain between 29 and 42 d in the control broiler line, daily weight gain between 29 and 42 d in Cornish, and body weights at 42 d as well as daily weight gain between 29 and 42 d in Aseel birds.

5. IGF1 expression varied among the breeds during embryonic and post-hatch periods. The expression among the haplogroups varied in different chicken tissues. The effect of haplogroup on myofibre number in pectoral muscle was non-significant, although there was significant variation in numbers between d 1 and d 42, and between broiler and layer lines.

6. It was concluded that the coding region of the IGF1 gene was polymorphic, expressed differentially during the pre-hatch and post-hatch periods, and haplogroups showed significant association with growth traits in chicken.  相似文献   

79.
Calcitonin is a calcium regulating peptide hormone with binding sites in kidney and bone as well as in the central nervous system. The mechanisms of signal transduction by calcitonin receptors were studied in a pig kidney cell line where the hormone was found to regulate sodium pumps. Calcitonin receptors activated the cyclic adenosine monophosphate (cAMP) or the protein kinase C (PKC) pathways. The two transduction pathways required guanosine triphosphate (GTP)-binding proteins (G proteins) (the choleratoxin sensitive Gs and the pertussis toxin sensitive Gi, respectively) and led to opposite biological responses. Moreover, selective activation of one or the other pathway was cell cycle-dependent. Therefore, calcitonin may induce different biological responses in target cells depending on their positions in the cell cycle. Such a modulation of ligand-induced responses could be of importance in rapidly growing cell populations such as during embryogenesis, growth, and tumor formation.  相似文献   
80.
The mode of degradation of various halogenated compounds in isolated pure cultures and the disposition of the degradative genes have been studied. In many cases the degradative genes are found to be clustered on plasmids and appear to be under positive control. Genetic selection in vivo and genetic manipulations in vitro have allowed construction of strains having wider biodegradative potentials than their natural counterparts. Molecular cloning of the degradative gene clusters for halogenated compounds in vectors with a broad host range also allows the transfer of such genes to a large number of Gram-negative bacteria. The application of 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)-degrading microorganisms has demonstrated the effectiveness of this strain in removing large amounts of 2,4,5-T from contaminated soil within a short period, and such soil has been shown to support the growth of plants normally sensitive to low concentrations of 2,4,5-T. The two major challenges that must be addressed in the near future are the development of appropriate microbial technology for the decontamination of soil containing hazardous halogenated compounds, and the promulgation of appropriate regulations to ensure the safety and well-being of the public during the application of genetically improved strains in an open environment.  相似文献   
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