摘要:

New researches on the culture « in vitro » of Aucuba japonica Thunb, – Caulinar fragments grownin vitroin nutrient media solidified with agar are compared with fragments grown on a filter paper support on unshaken liquid media. Tissue cultures ofAucubaare established putting down caulinar fragments just taken from the plant with isolated callus; subcultures are obtained more easily in July. We have observed that during the months of March or April, caulinar fragments, taken from the plant at various months of the year, of different ages and cultivated on various media, unexpectedly produce many roots.

ISSN:0017-0070    

DOI:10.1080/11263507409426337

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Contribution to the study of the marine algae of Sar Uanle (Southern Somalia). – Some preliminary researches have been carried out on the algal flora of Sar Uanle, lying south of Chisimaio in southern Somalia. The material first collected for these researches, that includes 69 species, appears mainly new for the Somalia coasts. This is due to the fact that the bibliography concerning this part of the western Indian ocean is very scarce. The presence of a remarkable percentage of species that are widely distributed in the indo-malaysian area, has been found out through the results of these enquiries.

ISSN:0017-0070    

DOI:10.1080/11263507409426338

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

The content of polyamines and RNA in isolated embryos from dry resting seeds ofdurumwheat has been determined. This, with the aim to investigate the variations of the polyamines and RNA amounts during the ageing process and to correlate them with the loss of germination capacity of the seeds. The results showed that the total polyamines increase while the RNA content decreases during the ageing of the embryos. Since no great difference exists as to the polyamine content between the embryos from seeds capable and incapable to germinate, it appears to be lacking a close relationship between the polyamine content and the germination capacity of the examined seeds. The decrease of the RNA content and the corresponding increase of the polyamine-N/RNA-nucleotide ratio, seem to suggest that the loss of germination capacity of the wheat seed could be related to impaired regulation properties during the ageing process.

ISSN:0017-0070    

DOI:10.1080/11263507409426339

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

An abnormal cell wall component in Trichophyton mentagrophytes treated with Phosfon D: ultrastructural demonstration. – Phosfon D, a growth-retarding chemical in higher plants, at the concentration of 5 × 10−4Minhibits the development of the dermatophytic fungusTrichophyton mentagrophytes. In the treated samples the diameter of the thallus is about 50% smaller than normal. The mycostatic effect of Phosfon D is accompanied by characteristic alterations of the cell wall ultrastructure with the appearance of dense granular masses not revealable after conventional fixation, but only after employing TAPO containing fixatives.

ISSN:0017-0070    

DOI:10.1080/11263507409426340

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Observations on the development cycle of the buds of male and female specimens of Ginkyo biloba L. – A study of the buds of long shood and short shoot of male and femaleGinkyo bilobaL. individuals reveals the following: 1) All the buds of the male individuals are bigger and round in shape while those of the female individuals are smaller and conical. 2) Among individuals of the same sex there are no differences between the buds of long and short shoots except that the latter are always bigger. 3) All the buds, both male and female, show a constant number of buds scales (7–14), embryonic leaves (3–7) and leaf primordia (3–4). 4) The increase in diameters is greater in the male than in the female buds. 5) When opening, the buds of the male short shoots can get as big as 11,5 mm × 11,5 mm and those of the female short shoots 5 mmx4 mm. At this time, the long shoots of both sexes show a less marked differences in size (♂ 5 mm × 5 mm; 9 4 mm × 3,5 mm). 6) The male buds of both long and short shoots are always mixed, that is they are provided with a very small apex and pollen sacs. Only on exceptional cases has sterility been observed. On the other hand female buds are mixed, that is they are provided with a shoot apex and ovules, only in the long shoots of three or more years of age and not always; while the buds of the long shoots are always sterile. 7) Opening of the buds, which in both sexes occurs from the base upwards, takes place at the middle of March in the male and in the first decade of April in the female individuals. 8) The appearence of sex, starting from the base, takes place at an earlier time in male individuals. In fact in the buds of the male short shoots it appears as early as July. In the buds of the female short shoots it appears in October. 9) Pollen cones do not appear at the same time in all the buds of the two types of shoot. They are found in the buds of the short shoots in July, in October in the lateral buds of the long shoots and in November in the terminal buds of the same type of shoots. 10) Ovules appear only in some buds of short shoots three or more year old. They are never present in the long and short shoots one or two year old buds. 11) The dates of appearance of the pollen cones and ovules in our Florentine specimens are exactly the same as those reported by SPRECHER (1907) for theGinkyoplants growing in Geneva.

ISSN:0017-0070    

DOI:10.1080/11263507409426341

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0017-0070    

DOI:10.1080/11263507409426336

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor