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Il famoso entomologo italiano, mio maestro F. Silvestri e' gia' scomparso trent'anni. Io ricordo con un profondo sentimento a porpetua memoria di questo grand'uomo dell' epoca in campo entomologico, boun amico del popolo cinese. Nei cinquantacinque anni precedenti, egli venne in Cina e amava la Cina, eglisperava affettuosamente che la Cina potrebbe diventare uno stato ricco e forte, ilpopolo cinese potrebbe vivere felicemente, e le scienze cinesi (include anche la ento-  相似文献   

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Abstract

Karyotype features and microsporogenesis of Tripogandra diuretica (Mart.) Handlos and Tripogandra glandulosa (Seub.) Rohw. from 15 NE Argentina accessions are analysed via classical cytogenetics, CMA/DA/DAPI and Ag-NOR. The karyotype of T. glandulosa (2n = 2x = 16; 2m + 6sm + 8st) is bimodal (A 2 = 0.37; R = 2.65) and asymmetrical (A 1 = 0.63; i = 26.06; r > 2 = 0.88) (3B-Stebbins) with a genome size of 33.28 μm; two pairs are satellited, CMA+ and NOR-actives. Another four CMA+ loci and DAPI+ universal centromeric heterochromatin occur. Microsporogenesis is normal (pollen viability short stamens = 97.8%; large = 96.7%), meiotic behaviour is regular and chromosomes pair as 8II. The karyotype of T. diuretica (2n = 8x = 64; 8m + 24sm + 32st) is bimodal (A 2 = 0.27; R = 2.54) and asymmetrical (A 1 = 0.60; i = 27.32; r > 2 = 0.88) (3B-Stebbins); additionally, two pairs are satellited. Microsporogenesis is normal (short stamens = 77.8%; large = 68.5%), except for micronuclei and low pollen viability in some accessions. Meiotic behaviour is regular with 32II, acting as a cytological diploid, however the arrangement of the haploid karyotype suggests that T. diuretica, which also exhibits a reduction of the genome size (18.58 μm), constitutes an auto-octoploid taxa. Additionally, both species share cytological features common to karyotype orthoselection.  相似文献   

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Riassunto Sono stati effettuati tre anni (1984–86) di osservazioni epidemiologiche ed aerobiologiche per ricercare la relazione esistente tra concentrazione pollinica giornaliera delle Oleacee nell' atmosfera della città di Palermo e numero di casi di pollinosi dovute a tale polline. I dati aerobiologici sono stati ottenuti con un campionatore volumetrico VPPS 2000. Questi, elaborati con il metodo della media mobile su 7 giorni e correlati con i dati epidemiologici, hanno evidenziato che, nel nostro territorio, le famiglie di pollini che rivestono importanza clinica sono tre: Urticacee, prevalentemente Parietaria, Graminacee ed Oleacee, prevalentemente Olea europaéa. Le Oleacee occupano il terzo posto nel determinismo delle pollinosi (21,76% di tutte le pollinosi), mentre dal punto di vista aerobiologico sono al secondo posto. La mancanza di proporzionalità diretta è da mettere in relazione, verosimilmente, con il breve periodo sintomatologico e con un basso potere allergizzante di tale aeroallergene. E' stato registrato, negli ultimi dieci anni, anche in Sicilia, un aumento della frequenza di sensibilizzazione verso il polline delle Oleacee.   相似文献   

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A sandy culture experiment was conducted to investigate the effects of exogenous CaCl2 on the indole alkaloid accumulation in Catharanthus roseus under salt stress. One-month seedlings of C. roseus were treated with the different concentrations of NaCl (0, 50, and 100 mmol l? 1) and 7.5 mmol l? 1 CaCl2. The plant samples were analyzed after 7 days of the treatments. The NaCl-stressed plants showed decrease of fresh and dry weight and increase of malondialdehyde (MDA) content compared to control. Tryptophan decarboxylase (TDC) activity increased significantly under 50 mmol l? 1 NaCl without CaCl2 addition, 50 mmol l? 1 NaCl with 7.5 mmol l? 1 CaCl2, and CaCl2 treatment without NaCl addition. There was a significant increase in peroxidase activity under NaCl stress compared to control. The vindoline, catharanthine, vincristine, and vinblastine contents increased under salt stress (especially with 50 mmol l? 1 NaCl treatment with or without CaCl2). Addition of CaCl2 to NaCl-stressed plants increased biomass, TDC activity, vindoline, and catharanthine contents and lowered MDA and vincirstine contents compared to the plants without CaCl2. The plants treated with CaCl2 alone showed higher TDC activity, vindoline, catharanthine, and vinblastine content when compared to control. The results showed that exogenous CaCl2 could promote the indole alkaloid metabolism under salt stress.  相似文献   

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Nomenclatural notes on the aggregate Polycarpon tetraphyllum (Caryophyllaceae) are discussed. The names Hagaea alsinifolia, H. polycarpoides, Poycarpon colomense, P. diphyllum, and P. floribundum are typified, respectively, on an iconography by Boccone (lectotype), and specimens preserved in PAL (neotype), JE (lectotype), MA (Herbarium Cavanilles, lectotype), and COI (Herbarium Willkomm, lectotype). For the nomenclatural purposes, the names P. bivonae (nom. nov. pro P. polycarpoides), P. herniarioides (holotype in K), P. peploides (nom. superfl.etnom. illeg. according to the Arts. 52.1 and 52.2 of the ICN), P. polycarpoides subsp. catalaunicum (holotype in BC), and P. rotundifolium (holotype in LY-Herbarium Rouy) are also discussed. P. floribundum is a heterotipic synonym of P. tetraphyllum s.s. A new synonym (P. tetraphyllum = P. rotundifolium) and three new combinations (P. tetraphyllum subsp. colomense, P. tetraphyllum subsp. herniarioides and P. tetraphyllum subsp. catalunicum) are proposed according to the current concept in Polycarpon.  相似文献   

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