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1.
Praveen C. Verma Debasis Chakrabarty Satya Narayan Jena Devesh K. Mishra Pradhyumna K. Singh Samir V. Sawant Rakesh Tuli 《Industrial Crops and Products》2009,29(2-3):581-589
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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Moharana P. C. Jena R. K. Pradhan U. K. Nogiya M. Tailor B. L. Singh R. S. Singh S. K. 《Precision Agriculture》2020,21(2):426-448
Precision Agriculture - Delineation of management zones (MZs) are needed to manage fields in order to maximize economic return, minimize environmental impact, and improve soil and crop management.... 相似文献
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Freshwater mussel Lamellidens marginalis showed a Ca2+-stimulated ATPase activity in the microsomal fraction of gill. Mg2+ was also found to be an activating cation for this ATPase enzyme. Ca2+ ATPase showed maximal activity at 40 °C and between pH 7.5–8.0. Substrate specificity of Ca2+ ATPase was highest with ATP, followed by GTP and other trinucleotides such as UTP, CTP and ADP also showed some amount of hydrolysis. Ca2+ ATPase showed slight inhibition with ruthenium red and sodium vanadate and is insensitive to sodium azide, ouabain, oligomycin B and phenylalanine. Heavy metals like Hg2+, Cu2+ and Zn2+ showed 50% inhibition of Ca2+ ATPase activity at concentrations of 0.25 mM, 0.5 mM and 1 mM, respectively whereas Cd2+ and Ni2+ showed 39% and 28% inhibition of enzyme activity at 1 mM concentrations. 相似文献
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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
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Pratap Chandra Das Joykrushna Jena Bibhudatta Mishra Bikash Kumar Pati 《Journal of the World Aquaculture Society》2012,43(1):128-134
Impact of aeration on growth of silver barb, Puntius gonionotus during fingerling rearing was studied through a 100‐d rearing experiment conducted in 18 concrete tanks of 50 m2 (10 × 5 × 1.2 m) size. Fry (0.74 ± 0.27 g, 35 ± 6 mm) were stocked in the experimental tanks at three stocking densities (25, 50, and 75 fry/m2) and were evaluated with and without provision of 6 h (2400–0600 h) of night time aeration. Aeration resulted in higher pH and dissolved oxygen regime and increased fingerling length and weight. The results suggest a rearing density of 75/m2 to be ideal for rearing fry to fingerling of this species when aeration is provided, whereas, under non‐aerated condition, rearing the fry to fingerling stage at 50/m2 was found advantageous over those at 25 and 75/m2. 相似文献
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Objective To measure the prevalence of megabacteria in budgerigar-breeding colonies and to evaluate possible methods to reduce the prevalence.
Design A monitoring study over several years.
Sample population Two budgerigar ( Melopsittacus undulatus ) colonies with over 300 birds each.
Procedure The prevalence of megabacteria in the faeces in two budgerigar breeding colonies, colony 1 and 2, was determined by faecal examination of each bird. Following an initial survey (1990), most of the birds that were scored 2+ or more were culled and a management practice was implemented to discriminate against positive birds. Consecutive yearly surveys (1991, 1992) were conducted on the young birds bred in these colonies. The prevalence of megabacteria in colony 2 was also evaluated in 1994 and 1996 after all the birds were treated with amphotericin B administered in drinking water.
Results The prevalence of megabacteria in the two colonies was significantly (P < 0.001) different. Overall the prevalence of megabacteria adjusted for colony differences was significantly higher (P < 0.025) in males compared to females. Age was not an influencing factor. After the initial survey, the prevalence in the offspring did not significantly (P > 0.05) decrease in the following two annual breeding seasons but by inference it did significantly decrease after amphotericin B treatment.
Conclusion The practice of culling most birds with more megabacteria in faeces and discriminating against positive birds when selecting birds for breeding or culling birds on show quality does not decrease megabacteria prevalence in the offspring. However, a reduction in prevalence does occur with administration of amphotericin B. Birds may have amphotericin B-resistant organisms and these birds need to be identified and culled. 相似文献
Design A monitoring study over several years.
Sample population Two budgerigar ( Melopsittacus undulatus ) colonies with over 300 birds each.
Procedure The prevalence of megabacteria in the faeces in two budgerigar breeding colonies, colony 1 and 2, was determined by faecal examination of each bird. Following an initial survey (1990), most of the birds that were scored 2+ or more were culled and a management practice was implemented to discriminate against positive birds. Consecutive yearly surveys (1991, 1992) were conducted on the young birds bred in these colonies. The prevalence of megabacteria in colony 2 was also evaluated in 1994 and 1996 after all the birds were treated with amphotericin B administered in drinking water.
Results The prevalence of megabacteria in the two colonies was significantly (P < 0.001) different. Overall the prevalence of megabacteria adjusted for colony differences was significantly higher (P < 0.025) in males compared to females. Age was not an influencing factor. After the initial survey, the prevalence in the offspring did not significantly (P > 0.05) decrease in the following two annual breeding seasons but by inference it did significantly decrease after amphotericin B treatment.
Conclusion The practice of culling most birds with more megabacteria in faeces and discriminating against positive birds when selecting birds for breeding or culling birds on show quality does not decrease megabacteria prevalence in the offspring. However, a reduction in prevalence does occur with administration of amphotericin B. Birds may have amphotericin B-resistant organisms and these birds need to be identified and culled. 相似文献
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