共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
Flowering and pollination biology ofChloranthus serratusandChloranthusfortuneiwere studied. Flowering took place from early Marchto midApril inCh. fortunei, and from April to September,the whole growth period, inCh. serratus.The flowering periodof an inflorescence ofCh. serratusaveraged about 8 d and anthesisof a single flower was 56 d. Flowers are slightly protogynous.The flower emitted fragrance when the androecium became white.Both species are entomophilous with thrips as exclusive pollinators.Under natural conditions, fruit set occurs mainly as a resultof cross-pollination, but self-pollination and agamospermy mayoccur in some cases. In flowers ofCh. fortuneiandCh. serratus,theincurved androecium, the carpel and the spike axis form a nearlyclosed chamber that contains the anthers and stigma. The developmentof a floral-axial chamber may be an important step towards amore economical and effective pollination system. Floral morphology,pollination biology and fossil evidence suggest that the mainevolutionary trend in the genusChloranthusis towards developmentof closed flowers. The fidelity of the relationshipbetweenChloranthusand thrips is regarded as a specialized featureof pollination biology and this relationship may have originatedearly in the evolutionary lineage.Copyright 1999 Annals of BotanyCompany Chloranthaceae,Chloranthus, Thysanoptera,flowering, floral-axial chamber, pollination, evolution trends. 相似文献
4.
5.
6.
《Inorganica chimica acta》1988,142(2):329-331
The complex (C5D5)2Yb(dme) (dme = 1,2- dimethoxyethane) has been prepared by reaction of Tl(C5D5) with ytterbium metal in dme and is isostructural with (C5H5)2Yb(dme). Thermal desolvation under vacuum yields (C5D5)2Yb, for which essentially identical high resolution neutron powder diffraction data were obtained at 294 K and 77 K, but the structure could not be determined. 相似文献
7.
8.
9.
Jaydip Mandal Sitakanta Pattnaik Pradeep K. Chand 《In vitro cellular & developmental biology. Plant》2000,36(4):287-292
Summary Propagation and conservation of four pharmaceutically important herbs, Ocimum americanum L. syn. O. canum Sims. (hoary basil); O basilicum L. (swett basil); O. gratissimum L. (shrubby basil); and O. sanctum L. (sacred basil) was attempted using synthetic seed technology. Synthetic seeds were produced by encapsulating axillary
vegetative buds harvested from garden-grown plants of these four Ocimum species in calcium alginate gel. The gel contained Murashige and Skoog (MS) nutrients and 1.1-4.4 μM benzyladenine (BA). Shoots emerged from the encapsulated buds on all six planting media tested. However, the highest frequency
shoot emergence and maximum number of shoots per bud were recorded on media containing BA. Of the six planting media tested,
both shoot and root emergence from the encapsulated buds in a single step was recorded on growth regulator-free MS medium
as well as on vermi-compost moistened with halfstrength MS medium. Rooted shoots were retrieved from the encapsulated buds
of O. americanum, O. basilicum, and O. sanctum on these two media, whereas shoots of O. gratissimum failed to root. The encapsulated buds could be stored for 60 d at 4°C. Plants retrieved from the encapsulated buds were hardened
off and established in soil. 相似文献
10.
11.
12.
13.
Grosfeld J Barthélémy D 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》2001,324(3):245-250
The aim of this study was to determine the dioecious or monoecious condition of Fitzroya cupressoides and Pilgerodendron uviferum. The study area lies west of the Nahuel Huapi National Park in northern Patagonia (Argentina), where these species form mixed stands. One hundred individuals of each species were studied over three successive years. The nature and position in the crown of their reproductive organs were recorded. Results showed that both species are dioecious. This feature has been confirmed on trees of these species growing in other sites within their natural distribution area in Argentina and Chile. 相似文献
14.
Walter Titz 《Plant Systematics and Evolution》1969,117(2):195-200
Zusammenfassung
A. sagittata (Bertol.) DC. von zehn Herkünften aus Europa ist mit 2 n=16 diploid.A. hirsuta (L.)Scop. s. str. einschließlich der sicherlich hierhergehörigen var.glaberrima
Wahlenb. von 30 europäischen Herkünften ist mit 2 n=32 tetraploid; diploide Pflanzen konnten beiA. hirsuta s. str. nicht gefunden werden.
Summary A. sagittata (Bertol.) DC. from 10 different places in Europe has 2 n=16 chromosomes and is diploid.A. hirsuta (L.)Scop. s. str., its var.glaberrima Wahlenb. being included, has been investigated from 30 provenances in Europe, it has the tetraploid chromosome number 2 n=32, diploid plants could not be found in this species.A. hirsuta var.glaberrima (2 n=32) is surely belonging toA. hirsuta s. str. and not toA. allionii (2 n=16).相似文献
15.
16.
17.
18.
19.
20.
M. G. Gilbert 《Nordic Journal of Botany》1986,6(2):139-141
Two new species, Rhus neoglutinosa M. Gilbert (Anacardiaceae) and Teclea borenensis M. Gilbert (Rutaceae) are described in preparation for the forthcoming Flora of Ethiopia. 相似文献