摘要:

AbstractC. SPEGAZZINI published in 1902 from ArgentinaC. purpurascensB. DE JUSS. ex JACQ. having seeds only with orange up to chestnut seed‐coat; c.b. for the seeds (for 1: 1.31–1.37 mm., for w: 1.20–1.28 mm.,n= 91) considerably overlaps the c.b. of the seeds (having the same colour of the seed‐coat) ofC. fallax(AELLEN) D. (c.b. for 1: 1.31–1.44 mm., for w: 1.16–1.26 mm.,n= 200). Seeds (identical or related with the seeds of C. SPEGAZZINI'S specimen) could have been introduced with wool to Europe. Here there took place their hybridization with European species of the range ofC. albumagg. and later there arose hybridogenous species:C. fallax(AELLEN). D. andC. pseudoborbasiiJ. MURR. These species have double seeds: a) seeds whose colour of the seed‐coat and the sizes ± agree with the colour and the sizes of seeds of C. SPEGAZZINI'S specimen; b) seeds with the black seed‐coat and ± the sizes of seeds of the species that the hybridizat

ISSN:0014-8962    

DOI:10.1002/fedr.19921030302

出版商:Wiley‐VCH Verlag    

年代:1992

数据来源: WILEY

ISSN:0014-8962    

DOI:10.1002/fedr.19921030303

出版商:Wiley‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractSixty local sugarcane clones from the sugarcane germplasm at Badeggi were studied cytologically. Chromosome numbers were determined from the root tip and all the investigated clones agree with the previous reports of chromosome numbers. Basic number of X = 6, 8, 10, 12 were used to determine the ploidy level of the clones. All the investigated clones were polyploids and 53.3 percent of these were octaploids.

ISSN:0014-8962    

DOI:10.1002/fedr.19921030304

出版商:Wiley‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractAnatomy of the fruit wall ofCalotropis, Tylophora, Gymnema, Marsdenia, Wattakaka, CeropegiaandLeptadeniawere studied for its taxonomic and phylogenetic significance. Epicarp is single layered inCalotropis, CeropegiaandLeptadenia, while inMarsdenia, Wattakaka, TylophoraandGymnemait is multilayered. Mesocarp is parenchymatous possessing aerenchymatous tissue in all the genera studied. Endocarp is multilayered and lignified. Dehiscence of the follicle is marginicidal. Factors responsible for dehiscence are also discussed.

ISSN:0014-8962    

DOI:10.1002/fedr.19921030305

出版商:Wiley‐VCH Verlag    

年代:1992

数据来源: WILEY

ISSN:0014-8962    

DOI:10.1002/fedr.19921030306

出版商:Wiley‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractFor 130 years transverse dimensions of softwood tracheids have been the subject of study. Selected references show that diameter and wall thickness of the cells have been more thoroughly studied than lumen diameter. An attempt was made to correlate these three anatomical parameters among each of them and with wood density in 15 coniferous tree species andGinkgo bilobaL. In the case of an old Scots pine (Pinus sylvestrisL.) it will be emphasized besides juvenile and mature wood the so‐called »overmature wood«, by which is assumed its formation being due to symptoms of senesce

ISSN:0014-8962    

DOI:10.1002/fedr.19921030307

出版商:Wiley‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractThe structure of the extrafloral nectaries inDesmanthus varigatuswas studied at the level of light microscope. A shallow cup shaped, non‐porate nectary present at the rachis base and had developed from a group of initials of hypodermal origin. The mature nectaries were supplied by phloem and had non‐glandular, cuticularized trichomes at their epidermal surfaces. Secreting nectaries appeared susceptable to fungal growth. Only non‐agressive ants visit the nectaries and the secretion was observed during morning hours. It is suggested that ants may have a little role in plant de

ISSN:0014-8962    

DOI:10.1002/fedr.19921030308

出版商:Wiley‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractFür die zentralen Hochanden Perus wird die Herkunft der Flora auf Gattungsebene analysiert. Dabei werden andische, tropisch‐subtropische, holarktische und kosmopolitische Florenelemente unterschieden. Neben der Präsenz der Sippen findet auch die Frequenz, basierend auf pflanzensoziologischen Erhebungen, Berücksichtigung. Die prozentuale Berechnung erfolgt für die einzelnen Höhenstufen und pflanzensoziologischen Klassen ge

ISSN:0014-8962    

DOI:10.1002/fedr.19921030309

出版商:Wiley‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractIn Far East (mainly in Japan), considerable attention has been devoted to weeds of many types of seminatural and artificial vegetation. It allows us to compare the weed flora of artifical grasslands (seeded and planted) dominated byZoysia japonicain Pyongyang (the capital of North Korea) with other similar communities.Some of the dominant or common species of the artificial monocoenoses withZ. japonica(Tables 1a, 1b, 2; Fig. 4) may be considered dangerous for field crops and seeded meadows. There are, especially,Kummerowia striataandViola mandshurica.Of the rare species there areOxalis corniculata, Equisetum arvenseandSetaria viridis.Many weed species of the studied artificial grasslands also occur in intensive pastures withZoysia japonicain Japan (Table 3). This similarity of both vegetation types is ascribed to a similar way of disturbance of vegetation and soil surface (grazing and trampling by livestock on the one hand and cutting and weeding on the other) and by the occurrence of the same dominant.Artificial grasslands in Pyongyang were classified asZoysia japonicacommunity. Four groups of phytosociological relevés were distinguished by using the ordination technique DCA and its comparison with BRAUN‐BLANQUET (Tables 1a, 1b, 2; Fig.

ISSN:0014-8962    

DOI:10.1002/fedr.19921030310

出版商:Wiley‐VCH Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractRocky areas constitute unfavourable habitat for plant growth due to lack of soil, water and nutrients. The number of plants were more during wet season than the dry season. Based on the Importance Value Index (IVI), nineteen species organized intoEuphorbia‐Tridax‐Commelinacommunity.Study was focussed on dominant plants, namely love grassEragrostis tenella(L.) P. BEAUV. ex ROEM. et SCHULT.), garden spurge (Euphorbia hirtaL.), guinea grass (Panicum maximumJACQ.) andTridax procumbensL. Guinea grass was the tallest having highest specific leaf area, and contributed maximum biomass. The highest leaf‐area ratio wa for garden spurge. A high association index exist between garden spurge andT. procumbens; love grass andT. procumbens; and guinea grass and red spiderling (Boerhavia coccinea). Conductivity, moisture content, organic matter, contents of potassium und sodium were higher in the soils from crevices as compared to that from rock surface,pH was alkaline. Seeds of love grass were the lightest. The percentage germination for the four plants were maximum in continuous light, at 20 °C and when sown at surfac

ISSN:0014-8962    

DOI:10.1002/fedr.19921030311

出版商:Wiley‐VCH Verlag    

年代:1992

数据来源: WILEY