Euonymus Research Articles

Hydrocarbons and triterpenes of the leaves of Euonymus latifolius

Hydrocarbons and triterpenes of the leaves of Euonymus latifolius

The mechanical transmission of euonymus mosaic virus, maple leaf perforation by leaf extract or leaf nucleic acid to herbaceous plants

Conditions for the mechanical transmission of some woody viruses to herbaceous hosts were studied. Viruses from naturally-infected spindle tree (Euonymus europaea) and maple (Acer pseudoplatanus) leaves were mechanically transmitted by the homogenate prepared by using charcoal and celite to beans (Phaseolus vulqaris cv. Kocovska and Perlicka). The transmission of Euonymus mosaic virus and maple leaf perforation by nucleic acids prepared from naturally infected woody plants was also successful.

Observations On Longidorus Euonymus N.Sp. and Xiphinema v uIttenezi Luc Et Al., 1964 (Nematoda: Dorylaimida) Associated With Spindle Trees Infected With Euonymus Mosaic Virus in Czechoslovakia

A needle nematode, Longidorus euonymus n.sp. is described; it was frequently found with a dagger nematode Xiphinema vuittenezi Luc et al., 1964 in the rhizosphere of Spindle trees (Eunoymus europaeus L.) that were often infected with euonymus mosaic virus (EMV) in different localities of the Bratislava district. L. euonymus n. sp. is most similar to L. closelongatus Stoyanov, 1964 and L. cohni Heyns, 1969 but has a much shorter odontostyle than either of these and a relatively fatter body than L. cohni; it also resembles L. vineacola Sturhan & Weischer, 1964 but has a more offset lip region, shorter odontostyle and relatively longer female tail; it is generally larger than L. attenuatus Hooper, 1961 and L. elongatus (de Man, 1876) with a more offset lip region than L. elongatus and a wider and more bluntly rounded female tail than either of these species. Details are also given of juvenile stages. In transmission trials, juveniles and females of L. euonymus acquired EMV from mechanically inoculated cucumber-plants and transmitted it to healthy cucumber-plants but juveniles and females of X. vuittenezi failed to do so under the same conditions. L. euonymus was not necessarily responsible for the incidence of EMV on Spindle trees because the fungus Olpidium brassicae, that also transmits this virus, was present at most sites.

Constituents of euonymous europeas

Constituents of euonymous europeas

HOST FINDING BY APHIDS IN THE FIELD: GYNOPARAE OF MYZUS PERSICAE (SULZER)

Attempts to test experimentally the theory of olfactory attraction to host plants gave negative results, and more conclusive evidence was sought by recording the behaviour of host‐finding migrants in the field. The first of three occasions when the natural alighting rate was high enough for comparative purposes was an autumn migration dominated by Myzus persicae returning to its specific overwintering host, the peach tree.The proportion of M. persicae gynoparae among all aphids caught alighting on a spindle tree, where persicae does not overwinter, was as high as on peach. The much heavier accumulation of migrants on the peach was evidently due, not to their differential alightment, but to their differential rate of departure, with a longer average stay on the peach. The proportion of persicae gynoparae was smaller in catches on transparent sticky traps than among alighters on the trees, and they avoided alighting on brussels sprout plants more often than on peach. Only a fraction of those that approached the plants alighted, even on peach; and only a small fraction of those that did alight, stayed, even on peach.There was appreciable colonization of spindle and sprouts by the M. persicae gynoparae and some ‘wasted’ oviposition by their progeny on spindle. After the migration was over the peach leaves entered the last stages of senescence before the spindle leaves, and persicae gynoparae (no longer able to fly) that were given access to both at that time, settled preferentially on spindle. The distribution of males created the impression that they were less host‐specific than gynoparae.

A historical study of windbreaks on farm fields in the Musashi Plain.

A brief study from agricultural and historical points of view was made on the development of windbreaks on the Musashi plain in the Kanto district. Significance of the windbreak for farming in that district, where fields are very often exposed to strong winds in the season from January to March, had attracted farmers' attention from old times, and been mentioned in many of the literatures and narratives referred to by the author. Nowadays, we can see many farm-fields which are provided with well-arranged windbreaks. On the other hand, however, we also find some fields with much disarranged windbreaks or even with none. The author indicated the fact that the extent of completion of windbreaks might be considered to relate more directly to the origin of the village to which it belongs than to the lay of the field and its soil conditions. The villages on the plain may be divided into two types as are shown in Fig. 1 and 2 according to the mode of land allotment and the shape of the field owned by each farmer. The village type of Fit. 1 is unsuitable for establishing windbreaks and the type of Fig. 2 is suitable. And the older settlements are generally of the former type and their windbreaks are disarranged or lacking, while the newer ones are of the latter type and are furnished with well arranged windbreaks. The author examined the kinds of plants used as windbreaks in that plain, which changed in accordance to the change of economical conditions of the farmers, the most probable chronological order being assumed as follows; Utsugi (Deutzia crenate Sieb. et Zucc.)-tea plant (Thea sinesis L.)-azalea plant (Rhododendron spp.)-spindle tree (Euonymus japonica Thund.)-Sawara (Chamaecyparis pisifera Endl.)

A Synopsis of the Genus Euonymus L.

A Synopsis of the Genus Euonymus L.

THE DISTRIBUTION OF APHID INFESTATION IN RELATION TO LEAF AGE

The leaf‐by‐leaf distributions of free infestations of viviparous Myzus persicae (Sulz.) and Aphis fabae Scop, were recorded on sugar‐beet plants and spindle bushes in pots in the greenhouse, and the distributions of the various seasonal forms of A. fabae were recorded on the same plants growing naturally outdoors. The aphid distributions were related to the ages of the leaves estimated on an arbitrary scale of ten types of leaf distinguished by degree of unfurling and colour. The diverse types of distribution recorded were all reducible to a common general pattern: growing and senescing leaves were more susceptible to colonization than maturing, mature and dying leaves. The resultant two‐peaked curve of aphid density on a series of leaves at successive stages of development was found in its entirety on certain sugar‐beet plants, but part only of the complete curve was usually found, owing to the incomplete range of leaf ages present on any one plant, particularly on the spindle tree.Fundatrigeniae were found colonizing sugar beet, and spring and summer migrants were found starting colonies on the spindle tree. The normal association of each seasonal form of the aphid either with the ‘primary’ winter host, or with a ‘secondary’ summer host, but not with both, is therefore not obligatory. It is attributed to the normal inaccessibility of summer hosts to fundatrigeniae and the normal unsuitability of the winter host when the ‘alienicolae’ are migrating and its leaves are mature.When M. persicae and A. fabae were infesting the same plant at the same time, their distributions were broadly alike, but M. persicae extended on to both younger and older leaves than did A. fabae and more strictly avoided the more mature leaves. Hence it is suggested that the degree of adaptation of a given aphid to a given plant may be gauged by the extent to which the aphid can colonize the plant's leaves not only when they are growing and senescing but also when they are mature and fully functional.

Euonymus frigidus Wall and Its Allies

Euonymus frigidus Wall and Its Allies

Distribution of Spindle (Euonymus europaeus) in Great Britain

THE Biology War Committee has been requested by the Agricultural Research Council to collect information and afterwards to plan sample surveys of the distribution of the spindle tree (Euonymus europaeus) in Great Britain. This scheme is part of the general research programme into the biology of the bean aphis (Aphis fabœ (A. rumicis)) which overwinters on this plant. The damage done by the bean aphis to the sugar-beet crop alone is estimated to reach a million pounds in some seasons, and proper knowledge of the distribution of its primary winter host is essential in any consideration of the problems of control. The Committee therefore asks for the following information from anyone able to supply it: (1) The exact location (reference one inch or six inch map if possible) of areas which can be put in the following categories: (i) spindle totally absent; (ii) spindle rare or occasional (isolated bushes 1–2 plants per square mile); (iii) spindle frequent (intermediate density between (ii) and (iv)); (iv) spindle unusually abundant (at least a hundred bushes per acre or ten plants per 100 yards of hedgerow); (data for Euonymus spp. in gardens should not be included). (2) The proportion by area which falls into each of the four foregoing categories of density. (3) The differences in (a) geological formation, (b) soil, (c) drainage, (d) altitude, (e) aspect, (f) other factors, which might influence the distribution of spindle. Such information should be sent before August 31 to Mr. G, E. Blackman, Hon. Secretary, Biology War Committee, Imperial College of Science and Technology, London, S.W.7.

Control of the Euonymous Scale

Control of the Euonymous Scale

Tennyson and the Spindle tree

Tennyson and the Spindle tree Get access J. Goudge J. Goudge 1Swindon Search for other works by this author on: Oxford Academic Google Scholar Notes and Queries, Volume s10-VI, Issue 150, 10 November 1906, Page 368, https://doi.org/10.1093/nq/s10-VI.150.368h Published: 10 November 1906