Comprehensive transcriptome analysis of grafting onto Artemisia scoparia W. to affect the aphid resistance of chrysanthemum (Chrysanthemum morifolium T.).

BACKGROUND: Aphid (Macrosiphoniella sanbourni) stress drastically influences the yield and quality of chrysanthemum, and grafting has been widely used to improve tolerance to biotic and abiotic stresses. However, the effect of grafting on the resistance of chrysanthemum to aphids remains unclear. Therefore, we used the RNA-Seq platform to perform a de novo transcriptome assembly to analyze the self-rooted grafted chrysanthemum (Chrysanthemum morifolium T. 'Hangbaiju') and the grafted Artermisia-chrysanthemum (grafted onto Artemisia scoparia W.) transcription response to aphid stress. RESULTS: The results showed that there were 1337 differentially expressed genes (DEGs), among which 680 were upregulated and 667 were downregulated, in the grafted Artemisia-chrysanthemum compared to the self-rooted grafted chrysanthemum. These genes were mainly involved in sucrose metabolism, the biosynthesis of secondary metabolites, the plant hormone signaling pathway and the plant-to-pathogen pathway. KEGG and GO enrichment analyses revealed the coordinated upregulation of these genes from numerous functional categories related to aphid stress responses. In addition, we determined the physiological indicators of chrysanthemum under aphid stress, and the results were consistent with the molecular sequencing results. All evidence indicated that grafting chrysanthemum onto A. scoparia W. upregulated aphid stress responses in chrysanthemum. CONCLUSION: In summary, our study presents a genome-wide transcript profile of the self-rooted grafted chrysanthemum and the grafted Artemisia-chrysanthemum and provides insights into the molecular mechanisms of C. morifolium T. in response to aphid infestation. These data will contribute to further studies of aphid tolerance and the exploration of new candidate genes for chrysanthemum molecular breeding.

Three new eudesmanes from Artemisia japonica.

Three new eudesmanes, named artemisidiols A-C, together with eight known compounds, were isolated from the leaves of Artemisia japonica Thunb. (Asteraceae). Their structures were determined on the basis of spectroscopic data. Although oxygenated eudesmanes frequently occur in Asteraceae plants, the 1α,6α,8α-oxygenated pattern of artemisidiols A-C has not been previously reported.

Phytohormones in Japanese mugwort gall induction by a gall-inducing gall midge.

A variety of insect species induce galls on host plants. Liquid chromatographic/tandem mass spectrometric analyses showed that a gall midge (Rhopalomyia yomogicola) that induces galls on Artemisia princeps contained high levels of indole-3-acetic acid and cytokinins. The gall midge larvae also synthesized indole-3-acetic acid from tryptophan. Close observation of gall tissue sections indicated that the larval chamber was surrounded by layers of cells having secondary cell walls with extensive lignin deposition, except for the part of the gall that constituted the feeding nutritive tissue which was composed of small cells negatively stained for lignin. The differences between these two types of tissue were confirmed by an expression analysis of the genes involved in the synthesis of the secondary cell wall. Phytohormones may have functioned in maintaining the feeding part of the gall as fresh nutritive tissue. Together with the results in our previous study, those presented here suggest the importance of phytohormones in gall induction.

Variation in bioactive principles of Artemisia amygdalina Decne. in wild and tissue culture regenerants.

Wild and tissue culture raised regenerants of Artemisia amygdalina, a critically endangered and endemic plant of Kashmir and North West Frontier Provinces of Pakistan were screened for the amount of bioactive principles and in particular antimalarial compound artemesinin. Phytochemical screening of extracts revealed the presence of terpenes, alkaloids, phenolics, tannins (polyphenolics), cardiac glycosides and steroids in wild (aerial, inflorescence) and tissue culture regenerants (in vitro grown plant, callus and green house acclimatized plants). HPLC of Artemisia amygdalina revealed the presence of artemesinin in petroleum ether extracts of wild aerial part, tissue culture raised plant and green house acclimatized plants. Acetonitrile and water in 70:30 ratios at flow rate of 1ml/min was standardised as mobile phase. Retention time for standard chromatogram was 6.7. Wild inflorescences and callus does not produce artemesinin. This is the first report of phytochemical screening and artemesinin estimation of wild and tissue culture raised regenerants of Artemisia amygdalina.

[Morphological and microscopic identification of herba artemisiae scopariae and its adulterants].

Pharmacognostical studies of Herba Artemisiae Scopariae and its adulterants were compared on morphological and microscopic characteristics. The detailed characteristics of powder microscopic identification were described.

[Pharmacognostical identification of Artemisia argyi and Artemisia indica].

This paper reported the identification of Artemisia argyi and A. indica on their macroscopical and microscopical chracteristics, TLC and UV spectra. It provides a basis for their differentication, exploitage and utilization.

The capturing of pollens in the atmosphere of La Laguna City, Tenerife, Canary Islands 1990-1995.

This paper forms part of a Doctorate Thesis, carried out in the Allergy and Immunology Department of the Nuestra Señora de la Candelaria Hospital, Tenerife, entitled "Epidemiology of Pollens on the Island of Tenerife. Allergy to Pollen". This paper deals with the capturing of pollen in the atmosphere of the city of La Laguna, Tenerife, during the period 1990-1995, and demonstrates that the Occidental Islands of the Canarian Archipelago are similar to a miniature continent with a special microclimate and a large amount of vegetation, where all classes of pollen can be found given the large variety of plants and trees including native species. High concentrations of more than 50 grains of pollen per m3 can be found in the air of the Occidental Islands, above all wild grasses, cultivated grasses, weeds, Artemisa vulgaris, Parietaria officinalis and Plantago lanceolata, and in a lowe proportion, Cupressaceae, Pinaceas, Mercurialis and Rumex. We have pollen concentrations very similar to other parts of the continent.