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1.
Three new furanopyridine alkaloids, namely glypenfurans A–C (1–3), were isolated from the leaves of Glycosmis pentaphylla together with six known furoquinoline alkaloids. Their structures were determined by extensive spectral analysis (UV, IR, MS, 1D and 2D NMR). 相似文献
2.
Mono- and sesqui-terpenes of individual oil glands of Citrus latipes fruits were analyzed for their homogeneity. The effect of oleocellosis, desiccation, Penicillium and Phytophthora infection upon the individual terpene components was investigated and expressed in a discriminant analysis and in canonical variables. Each oil gland contained the entire spectrum of terpenes specific for each species, and the biggest difference in affected glands was due to Penicillium infection. 相似文献
3.
The coumarins, isoimperatorin, isomeranzin, meranzin hydrate, oxypeucedanin, oxypeucedanin hydrate, oxypeucedanin methanolate and umbelliferone and the triterpene, friedoolean-14-en-3β-ol (taraxerol) were isolated from leaves of Skimmia japonica. 相似文献
4.
Hiroshi Furukawa 《Phytochemistry》1982,21(7):1771-1773
Two new acridone alkaloids, severifoline and N-methylseverifoline along with the known alkaloids, N-methylatalaphylline, atalaphyllinine and 5-hydroxy-N-methylseverifoline, were isolated from the root bark of Severinia buxifolia. The structures of severifoline and N-methylseverifoline were established by chemical and spectroscopic methods. 相似文献
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J. -Y. Fann A. Kovarik V. Hemleben N. I. Tsirekidze T. G. Beridze 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,103(6-7):1068-1073
Highly repeated satellite DNA (stDNA) of citric plants was characterized by cloning and sequencing 10–14 repeats of each plant
(Citrus limon, C. sinensis, C. ichangensis, Poncirus trifoliata). The monomers are mostly 181 bp in length with a GC-content between 60% and 68% (significantly higher than the average GC-content
of the citrus group genomes). Similarity among the repeats indicates that they belong to a satellite family that underwent
species-specific modifications, which are reflected in the phylogenetic relationships. Curvature provoked by dA-stretches
of the repeats analyzed by gel shifts revealed structural conservation, even though the nucleotide sequences vary among species,
thereby probably supporting the heterochromatic structure of stDNA. We show that the species-specific modification of the
satellite consensus involves changes in the position and number of dA tracts. The molecule shapes of satellite oligomeres
predicted by computer modelling indicate a superhelical structure of the tandem repeats which is in a good agreement with
the satellite sequence dendrogram. The contribution of DNA bending elements to the evolution of plant satellite repeats is
discussed.
Received: 27 November 2000 / Accepted: 12 January 2001 相似文献
7.
A phytochemical investigation of secondary metabolites from Micromelum integerrimum was reported. Two new prenylated coumarins named as hydramicromelin D (1) and integerrimelin (2) were isolated along with 9 known coumarin derivatives. The chemical structures as well as relative stereochemistries of those coumarins were confirmed on the basis of extensive spectroscopic data interpretation and comparison with those previously published data. 相似文献
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10.
Oviposition behaviour and larval development of Anastrepha fraterculus from Argentina in citrus 下载免费PDF全文
M.J. Ruiz M.L. Juárez R.A. Alzogaray F. Arrighi L. Arroyo G. Gastaminza E. Willink A. Bardón M.T. Vera 《Entomologia Experimentalis et Applicata》2015,157(2):198-213
Citrus peel physicochemical attributes are considered the main components conferring partial or even total resistance to fruit fly (Diptera: Tephritidae) infestation. Fruit fly females adapt their ovipositional strategies to overcome such resistance. Here, we explored the effects of citrus species (Rutaceae) on the ovipositional behaviour of the South American fruit fly, Anastrepha fraterculus (Wiedemann), and on its immature development. Particularly, we investigated the effects of (1) citrus species on oviposition behaviour and immature development, (2) citrus species on oviposition preference and on the location of the eggs at different depth in the citrus peel, and (3) harvest season and post‐harvest storage time on oviposition behaviour and immature development in lemon. Citrus species influenced ovipositional behaviour and affected survival of immature stages. Females laid eggs in lemon [Citrus limon (L.) Burm.], orange [Citrus sinensis (L.) Osbeck], and grapefruit (Citrus paradisi Macfadyen). In orange and lemon, larvae were found dead close to the oviposition areas, suggesting chemically mediated resistance mechanisms. Under choice conditions, females preferred grapefruit over lemon and bigger clutches were found in the layers where embryonic development is favoured. Unsuitability of lemon as a medium to complete development was neither affected by harvest season nor by storage time of the fruit after harvest. The physical and chemical characteristics of the peel were distinctive to each citrus species and may have affected the specific levels of resistance of these citrus species to infestation by A. fraterculus. 相似文献