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Summary Chlorophytum borivilianum Sant. et Fernand. (‘Safed Musli’), an endangered Indian medicinal herb, is valued for its tuberous roots reputed to have aphrodisiac properties. Farmers in India cultivate this medicinal herb on a commercial scale because of its high economic value. To cater to the growing demand for planting material, a highly reproducible field-tested and cost-effective micropropagation scheme has been developed. Best shoot multiplication was achieved on agargelled Murashige and Skoog medium containing 22.2 μM 6-benzylaminopurine (BA) and 3% sucrose. Phytagel at 0.2% showed slightly better response than BDH agar in terms of shoot multiplication, but the use of BDH agar was preferred due to its low cost. With the optimized conditions, more than 15 000 plantlets could be produced in 20 wk. Plantlets subjected to hardening under agro-shadenet conditions during the monsoon months of high humidity showed better survival rate and growth compared to plantlets hardened in vitro and subsequently transferred to the greenhouse for acclimatization. Rate of plantlet survival was 87 and 90% under open field and agro-shadenet conditions, respectively. Plantlets grown ex vitro under agro-shadenet and field conditions produced tuberous roots which could be grown in the next season as a secondary propagule. We concluded that in vitro production of ‘Safed Musli’ was cost-effective compared to conventional propagation and holds great potential for commercial production.  相似文献   
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Single-nucleotide polymorphisms (SNPs) are the most frequent variations in the genome of any organism. SNP discovery approaches such as resequencing or data mining enable the identification of insertion deletion (indel) polymorphisms. These indels can be treated as biallelic markers and can be utilized for genetic mapping and diagnostics. In this study 655 indels have been identified by resequencing 502 maize (Zea mays) loci across 8 maize inbreds (selected for their high allelic variation). Of these 502 loci, 433 were polymorphic, with indels identified in 215 loci. Of the 655 indels identified, single-nucleotide indels accounted for more than half (54.8%) followed by two- and three-nucleotide indels. A high frequency of 6-base (3.4%) and 8-base (2.3%) indels were also observed. When analysis is restricted to the B73 and Mo17 genotypes, 53% of the loci analyzed contained indels, with 42% having an amplicon size difference. Three novel miniature inverted-repeat transposable element (MITE)-like sequences were identified as insertions near genes. The utility of indels as genetic markers was demonstrated by using indel polymorphisms to map 22 loci in a B73 × Mo17 recombinant inbred population. This paper clearly demonstrates that the resequencing of 3 EST sequence and the discovery and mapping of indel markers will position corresponding expressed genes on the genetic map.  相似文献   
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The protein content of tomato (Lycopersicon esculentum) xylem sap was found to change dramatically upon infection with the vascular wilt fungus Fusarium oxysporum. Peptide mass fingerprinting and mass spectrometric sequencing were used to identify the most abundant proteins appearing during compatible or incompatible interactions. A new member of the PR-5 family was identified that accumulated early in both types of interaction. Other pathogenesis-related proteins appeared in compatible interactions only, concomitantly with disease development. This study demonstrates the feasibility of using proteomics for the identification of known and novel proteins in xylem sap, and provides insights into plant-pathogen interactions in vascular wilt diseases.  相似文献   
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The Zebrafish Information Network (ZFIN) is a web based community resource that serves as a centralized location for the curation and integration of zebrafish genetic, genomic and developmental data. ZFIN is publicly accessible at http://zfin.org. ZFIN provides an integrated representation of mutants, genes, genetic markers, mapping panels, publications and community contact data. Recent enhancements to ZFIN include: (i) an anatomical dictionary that provides a controlled vocabulary of anatomical terms, grouped by developmental stages, that may be used to annotate and query gene expression data; (ii) gene expression data; (iii) expanded support for genome sequence; (iv) gene annotation using the standardized vocabulary of Gene Ontology (GO) terms that can be used to elucidate relationships between gene products in zebrafish and other organisms; and (v) collaborations with other databases (NCBI, Sanger Institute and SWISS-PROT) to provide standardization and interconnections based on shared curation.  相似文献   
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