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1.
Vanilla is a large genus of about 110 species in the orchid family (Orchidaceae), including the species Vanilla planifolia from which commercial vanilla flavoring is derived. Since most species of vanilla are considered rare and endangered there is an urgent need to conserve them through genetic analysis and propagation/conservation studies on this crop.The present study investigated the genetic diversity among nine leafy- and leaf-less Vanilla species employing 30 decamer RAPD primers and 10 ISSR primers. The species under study were diverse and displayed a range of variability (0–66% and 0–81% for RAPD and ISSR, respectively). A total of 154 RAPD polymorphic markers (83.24%, h = 0.378) and 93 ISSR polymorphic markers (86.11%, h = 0.363) were used to generate a genetic similarity matrix followed by the cluster analysis. Specific groupings were revealed by each cluster analysis with slight variation between two different markers. Among the nine species studied, V. planifolia, Vanilla aphylla and Vanilla tahitensis revealed very low level of variation within their collections, thus indicating a narrow genetic base. The large genetic distance of Vanilla andamanica from other species suggests its different origin. A close genetic affinity was observed between the pairs V. planifolia, V. tahitensis and Vanilla albida, V. aphylla. These are the first comparative results for RAPD and ISSR reporting inter-relationship among nine cultivated, wild and hybrid Vanilla species.  相似文献   
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The subterranean parts of many wild plants form an important constituent of traditional diet of the tribal inhabitants of Similipal Biosphere Reserve, Odisha especially in times of food scarcity during critical periods. However, no specific study has been made so far on this aspect. The present study was conducted during 2008–2012 as a search for sources of food and to assess the dietary diversity, consumption pattern, culinary uses and prioritized species of wild tuberous plants sustained by local tribes. The exploration and germplasm collection missions along with intensive botanical survey, focus group discussions, structured household interview and market survey were conducted in 30 villages interacting with 102 key informants of core and buffer zones. A total of 55 wild edible tuberous species representing 37 genera and 24 families were inventoried including 17 species used during food deficiency to meet seasonal shortages. The analyzed data contributed 5 use categories, 4 preparation methods, 7 kinds of food items, 10 species as children snacks, 35 species of pharma-foods and 20 prioritized species. Ten species were domesticated by tribes thus reducing threats on wild tubers and 20 species were traded in local markets to generate additional income exemplifying economic benefits from wild tubers. Seventeen species were identified as novel uses of food items from India. The findings suggested that the nutritional profile along with pharmaceutical attributes of preferred wild food plants be analyzed for recommending suitable species for better nutrition and development of nutraceuticals. Further, many genetic resources of these wild tuberous species of agri-horticultural importance constitute the wild genepool hence their economic and breeding potential along with desirable attributes need to be investigated for utilization in crop improvement programmes.  相似文献   
4.
The effects of including bovine lactoferrin (Lf) in the diet of the Asian catfish (Clarias batrachus) on specific and non-specific immunity as well as disease resistance were investigated. The catfish were fed four different diets for 2 weeks: a commercial diet as control and the same diet supplemented with 50, 100 and 200mg bovine Lf/kg feed. After 1 and 2 weeks, serum bacterial agglutination titre against Aeromonas hydrophila as a measure of specific immunity; natural serum haemolysin titre, lysozyme activity and oxidative radical production by neutrophils as a measure of non-specific immunity as well as disease resistance against A. hydrophila challenge to vaccinated and non-vaccinated animals were evaluated. The results showed that Lf supplements, particularly at 100mg level, significantly (P<0.05) enhanced serum lysozyme level, oxidative radical production and level of protection against A. hydrophila challenge in non-vaccinated animals irrespective of length of exposure. The specific immunity was not influenced by Lf feeding as evidenced from the bacterial agglutination titre and level of protection in vaccinated animals. As Lf feeding at 100mg/kg for 1 week is able to enhance the non-specific immunity and disease resistance of catfish efficiently, these results support the possible use of Lf as an immunostimulant for farmed catfish.  相似文献   
5.
In the present study the level of enzyme hydrolases (alkaline phosphatase, myeloperoxidase, elastase, arginase, lysozyme and β-galactosidase) of polymorphonuclear cell (PMN) granules in different ruminant species and their release in response to activation was studied. Buffalo PMN alkaline phosphatase activity was higher (P < 0.01) than in PMNs of cattle and goats. Interestingly, myeloperoxidase was higher in cattle PMNs and least in goat PMNs (P < 0.01), a similar pattern was observed in the distribution of enzyme arginase. As far as lysozyme is concerned, its activity was significantly higher (P < 0.01) in PMNs of buffaloes than in the case of cattle and goat PMNs. On activation, these cells released MPO and elastase, in all the species studied, while lysozyme was secreted only in buffalo PMN cells. Activity of certain enzymes related to oxidant defence systems such as glutathione peroxidase and glutathione reductase were higher in cattle and goats compared to that in buffaloes. These observations are likely to have bearing on immunodefense roles played by PMNs and reflected differences among the ruminant species studied.  相似文献   
6.
The taxonomy and phylogeny of Indian Citrus is revisited using PCR-RFLP of the trnD-trnT and rbcL-ORF 106 regions as well as sequence data analysis of the trnL-trnF intergenic spacer region of cpDNA. The study was based on 50 accessions of Citrus genotypes, collected from wild, semi-wild and domesticated stocks. Of the 13 restriction enzymes (RE) used for restriction digestion of the polymerase chain reaction (PCR) amplicons, four (Hinf I, Msp I, Alu I, Hae III) generated 47 restriction fragments, of which 24 (51%) were polymorphic. PCR-RFLP data showed a genetic distance ranging from 0 to 0.79 among 50 accessions of Citrus, and a cluster analysis, based on Neighbor-Joining (NJ) method, placed all the accessions in eight major clusters. Analysis of trnL-trnF sequences from 23 representative accessions of Citrus showed a pair-wise sequence divergence rate in the range of 0–0.064. NJ, minimum evolution (ME) and maximum parsimony (MP) analyses of trnL-trnF sequences produced phylogenetic trees, which placed all the 23 accessions in five clusters. PCR-RFLP analysis resulted in a well resolved phylogenetic tree with branches supported by moderate to high bootstrap values, while the trnL-trnF sequence-based trees showed only moderate to low bootstrap support for the internal tree branches, indicating uncertain origin of some Citrus genotypes. This study shows that the trnL-trnF spacer sequence data can detect genetic variation in Indian Citrus genotypes, but the utility of the data in inferring phylogeny at intra and inter-specific levels is limited probably by factors such as hybridization, bud mutations, apomixis and polyploidy. However, PCR-RFLP and trnL-trnF data supported the recognition of C. maxima, C. medica, and C. reticulata as the basal species of edible Citrus.  相似文献   
7.
An experiment was conducted to evaluate the rearing performance of different larval stages for optimum growth and survival during fingerling production of Clarias batrachus with an aim to reduce the rearing time of the catfish larvae in a hatchery system. The larvae were reared for 5, 10 and 15 days before stocking them in the nursery tanks. No significant (< 0.05) difference could be found in length increment at the end of first week of rearing. But the total length was reduced during rest three weeks in five days old larvae compared to that of other two higher age groups. In 5 days old larvae the reduced weight (< 0.05) was observed during the entire rearing period. However, the specific growth rate (SGR) did not vary among the groups. The survival rate as well as total biomass was decreased while stocking five days old larvae for rearing, compared to that of other two age groups.  相似文献   
8.
In order to determine the immunomodulatory effect of dietary levamisole in Asian catfish (Clarias batrachus), fish were fed four different diets for 10 days: a formulated diet as control and the same diet supplemented with 50, 150 or 450 mg levamisole kg?1 feed. The serum bacterial agglutination titre against Aeromonas hydrophila as a measure of specific immunity, serum haemagglutination titre, natural haemolytic complement activity (ACH50), myeloperoxidase and lysozyme activities, total protein level and oxidative radical production by neutrophils as a measure of non‐specific immunity as well as disease resistance against A. hydrophila challenge to separate vaccinated and non‐vaccinated groups were evaluated at 0, 1, 2 and 3 weeks after last administration of levamisole. Levamisole supplement at the lowest level (50 mg kg?1) significantly enhanced oxidative radical production and serum myeloperoxidase (MPO) content immediately after 10 days of feeding, which reached peak values after 3 and 2 weeks of feeding respectively. Haemolytic complement and haemagglutination titre were significantly enhanced after 3 and 1 weeks respectively. Haemolytic complement activity and MPO activities were significantly raised to 150 mg kg?1 after 3 and 2 weeks, respectively. At the highest level of levamisole feeding (450 mg kg?1) significant decreases in superoxide production and complement activity were measured immediately after levamisole feeding, which returned to the normal level after 1 week post‐ feeding. Fish were challenged with a virulent strain of A. hydrophila at 0, 1, 2 and 3 weeks after levamisole feeding, and the cumulative per cent survival was recorded over 10 days. Feeding levamisole at 50, 150 or 450 mg kg?1 increased per cent survival in vaccinated fish immediately after levamisole feeding, and survival was significantly higher at 450 mg kg?1. There was no difference in mortality patterns in non‐vaccinated fish. The results support the use of levamisole at 50 mg kg?1 feed for 10 days as an immunostimulant in Asian catfish farming.  相似文献   
9.
Biosurfactants are biomolecules produced by microorganisms, low in toxicity, biodegradable, and relatively easy to synthesize using renewable waste substrates. Biosurfactants are of great importance with a wide and versatile range of applications, including the bioremediation of contaminated sites. Plants may accumulate soil potentially toxic elements(PTEs), and the accumulation efficacy may be further enhanced by the biosurfactants produced by rhizospheric microorganisms. Occasionally, the growth of bacteria slows down in adverse conditions, such as highly contaminated soils with PTEs. In this context,the plant's phytoextraction capacity could be improved by the addition of metal-tolerant bacteria that produce biosurfactants. Several sources, categories,and bioavailability of PTEs in soil are reported in this article, with the focus on the cost-effective and sustainable soil remediation technologies, where biosurfactants are used as a remediation method. How rhizobacterial biosurfactants can improve PTE recovery capabilities of plants is discussed, and the molecular mechanisms in bacterial genomes that support the production of important biosurfactants are listed. The status and cost of commercial biosurfactant production in the international market are also presented.  相似文献   
10.
Mitochondrial DNA from two pairs of cytoplasmic male-sterile (cms) and maintainer lines of pearl millet was investigated by restriction-enzyme analysis and Southern-blot hybridization using three mitochondrial gene probes. Each pair of male-sterile and maintainer lines was of a different nuclear origin. The objective was to distinguish differences in the DNA base-sequence organization of the mitochondrial genomes of cms and maintainer lines from the two sources. Restriction-enzyme analysis revealed differences between the different cms and maintainer lines. Southern-blot hybridization experiments using cloned mitochondrial gene probes further distinguished differences between different lines. It is expected that the restriction-fragment-length polymorphisms revealed in the Southern-blot-hybridization experiments will be useful in distinguishing and classifying cms and maintainer lines obtained from different nuclear backgrounds.  相似文献   
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