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Diverse 2,3-substituted indanones are accessed in an efficient and robust protocol by a rhodium-catalyzed tandem carborhodium/cyclization and intramolecular proton shift pathway. The reaction is compatible with a broad range of functional internal acetylenes, especially for natural and functionalized alkynes derivatives, affording the desired indanones in good to excellent yields. Remarkably, this reaction features very mild and sustainable conditions using water as the sole solvent and without exogenous ligands. Control studies support that indanone is formed through the intramolecular proton transfer process from the key intermediate indenol.

Vaccinium arboreum is adapted to soils with low organic matter and high pH. It is considered as a potential blueberry rootstock. The objective of this research was to establish a rapid mass propagation protocol of V. arboreum through axillary shoots proliferation with minimum somaclonal variation. Nodal segments from cuttings were cultured on Driver and Kuniyaki walnut medium (DKW) with different cytokinins for initial culture establishment. DKW, woody plant medium (WPM), and Long and Preece medium (LP) were compared for best shoot proliferation. Zeatin (ZT) concentrations from 0 to 4.56 μM were evaluated for optimizing the concentration. Both in vitro and ex vitro rooting were evaluated. The pH tolerance of in vitro shoots was investigated by adjusting the media pH from 5 to 8.5. Best shoot proliferation was achieved by LP medium supplemented with 2.28 μM ZT and 0.05 μM indole-3-butyric acid (IBA). In vitro shoots proliferated best on medium pH 5, though the shoots could survive on pH 8. All the micropropagated shoots successfully rooted by ex vitro rooting after dipping with auxin. All rooted plantlets acclimatized and grew well in greenhouse. Micropropagation through axillary shoots proliferation is an efficient method to propagate true-to-type V. arboreum in large number for future use as rootstock.

Mannans are widespread hemicellulosic polysaccharides in plant cell walls. Hydrolysis of the internal beta-1,4-D: -mannopyranosyl linkage in the backbone of mannans is catalyzed by endo-beta-mannanase. Plant endo-beta-mannanase has been well studied for its function in seed germination. Its involvement in other plant biological processes, however, remains poorly characterized or elusive. The completed genome sequences of Arabidopsis (Arabidopsis thaliana), rice (Oryza sativa), and poplar (Populus trichocarpa) provide an opportunity to conduct comparative genomic analysis of endo-beta-mannanase genes in these three species. In silico sequence analysis led to the identification of eight, nine and 11 endo-beta-mannanase genes in the genomes of Arabidopsis, rice, and poplar, respectively. Sequence comparisons revealed the conserved amino acids and motifs that are critical for the active site of endo-beta-mannanases. Intron/exon structure analysis in conjunction with phylogenetic analysis implied that both intron gain and intron loss has played roles in the evolution of endo-beta-mannanase genes. The phylogenetic analysis that included the endo-beta-mannanases from plants and other organisms implied that plant endo-beta-mannanases have an ancient evolutionary origin. Comprehensive expression analysis of all Arabidopsis and rice endo-beta-mannanase genes showed divergent expression patterns of individual genes, suggesting that the enzymes encoded by these genes, while carrying out the same biochemical reaction, are involved in diverse biological processes.

To facilitate wheat breeding with the Ph1 gene, 19 sequence tagged-polymerase chain reaction (STS-PCR) primers developed previously from barley chromosome 5H were screened. One pair of STS-PCR primers differentiated 'Chinese Spring' (CS, Ph1) and the CS mutant (ph1b). The diagnostic fragment was 920 base pairs (bp) in size, designated as ABC 920 , and was located on the interstitial deletion of the long arm of chromosome SB of ph1b mutant. Plants with or without the Ph1 gene could be distinguished among 148 F 2 /97 BC, plants from the cross CS (Ph1) x CS mutant (ph1b) on the basis of the presence or absence of this fragment. Subsequently, two 24-mer sequence characterized amplified regions (SCAR) primers were developed on the basis of sequences at both ends of the ABC 920 fragment to generate a single amplified band in plants with the Ph1 genotype. The Ph1 and ph1b genotypes can be readily scored in the PCR products of individual plant DNA. This SCAR marker (SCABC 823 ) was used to facilitate the transfer of the ph1b locus into an elite wheat (Triticum aestivum L.) cultivar. This marker is expected to aid in gene transfer between wheat and its wild relatives.