摘要:

Mature thalli ofBoldia erythrosiphongen. et sp. nov. from Big Walker Creek, Giles Co., Va., are hollow, simple, or, rarely, branched tubular cylinders. The plants generally are from 1 to 20 cm in length and 0.1–1.5 cm in diameter, brownish‐red or olivaceous in color, and grow singly or in clusters from a multicellular holdfast. The vegetative portion of the thallus is essentially monostromatic, comprised of isodiametric, or slightly elongate, uninucleate cells with numerous parietal, simple or lobed, ribbon‐like chromatophore segments. Monospores are produced from narrow, branching filaments (derived from vegetative cells) which form a reticulate pattern in the intercellular matrix external to and at the juncture between groups of (usually 2, 4 or 8) vegetative cells. The spores are liberated singly and germinate into short, branched filaments. New plants arise from small, monostromatic discs of branching filaments united in a common matrix which become cushion‐like and ultimately produce saccate thalli. WhileBoldiashows affinities with certain members of the Bangiales, it cannot be assigned to any of the presently recognized families. Accordingly, it is placed in a new and distinct family,Boldiaceae,distinguished by the unique manner in which asexual spores are produced from filaments derived from vegetative cells, the filaments developing within the intercellular matrix of the thallus, as well as by the parietal chromatophores of the vegetative cells.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1964.tb06673.x

出版商:Wiley    

年代:1964

数据来源: WILEY

摘要:

Filtrates from certain liquid cultures ofChlorella vulgaris(Columbian strain) developed sufficient peroxide content, after a few days’ storage, to inhibit further growth ofChlorellawhen they were used to prepare fresh culture media. Similar inhibition was observed whenChlorellawas cultured in media containing various added organic peroxides. Growth ofChlorellawas not limited by autoinhibitor production under the conditions employed, and no peroxide or other inhibitor was detected in solvent extracts of the cells or fresh filtrates.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1964.tb06674.x

出版商:Wiley    

年代:1964

数据来源: WILEY

摘要:

The relation of the operation of the hexose monophosphate pathway to cellular particles ofUstilago maydiswas investigated. Results obtained indicate that extracts from which all microscopically visible particles had been removed could oxidize glucose through the hexose monophosphate pathway. By tracer techniques it was found that all, or almost all, released CO2was obtained from the number 1 carbon of glucose. Spectrophotometric studies demonstrated the presence of glucose‐6‐phosphate dehydrogenase and 6‐phosphogluconic acid dehydrogenase. Radiochromatographic studies indicated the formation by mitochondria‐free extracts of glucose‐6‐phosphate, 6‐phosphogluconic acid and possibly ribose‐5‐phosphate. These extracts could metabolize glucose and 6‐phosphogluconate with oxygen uptake. It was concluded that in this fungus the energy‐producing and decarboxylating steps of the hexose monophosphate pathway could operate with the uptake of O2in the absence of mitochondria. The dehydrogenases present in the supernatant solutions can cooperate with an electron transfer sequence to O2in the supernatant. Presumptive evidence for the presence and action of glucokinase and phosphoriboisomerase was provided by the results of the aforementioned experiments. Isolated mitochondria were found by spectrophotometric means to contain cytochrome c oxidase and DPNH oxidase. Mitochondria were capable of using succinate as a substrate with oxygen uptake. Under some conditions isolated mitochondria showed a high endogenous rate of metabolism which could be halted by KCN. The use of isotopic tracer techniques indicated that extracts containing mitochondria could carry out the decarboxylation of citric acid via the tricarboxylic acid cycle.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1964.tb06675.x

出版商:Wiley    

年代:1964

数据来源: WILEY

摘要:

Two distinct adult leaf forms, i.e., land and submerged leaves, of the aquatic fernMarsilea vestitawere collected from nature and were obtained from plants in sterile culture. The venation patterns and anatomy of these 2 adult leaf forms are presented in detail. Pinna development and the morphology of a third leaf form, i.e., floating leaves, are briefly considered. The differences in leaf form are ascribed to differences in the activity of the marginal meristem of the leaf.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1964.tb06676.x

出版商:Wiley    

年代:1964

数据来源: WILEY

摘要:

Although taxonomists interpret the ovaries of most cacti as inferior,3the inferior position has been derived in a very different manner from that in most flowering plants. In the classical situation, the dorsal sides of connate carpels arc invested by a floral tube (hypanthium) ; in Cactaceac, on the other hand, the dorsal sides of the carpels are mostly free—not invested by a floral tube. The ventral sutures are pulled downward during formation of the hollow receptacle so that they come to lie on the sides of a locule between flanges of tissue which represent the reduced remains of fused margins and lateral walls of adjacent carpels. The morphology of an individual carpel is like that of a pea pod which has been split midway between dorsal and ventral bundles, then opened up so that the dorsal segment projects upward, the ventral segment containing the ovules, downward. In most cacti, the ventral segments are adnate to the walls of a hollow floral receptacle. In all cases observed so far, the floor of the locule appears not to be invested by carpellary tissue—it is interpreted here as representing free recoptacular tissue. In other words, the morphological bases of cactus carpels are not at the bottom of the locule, but above it, where the dorsal and ventral bundle systems diverge from the recurrent receptacular bundles. This interpretation, like the more complex one offered by Buxbaum, explains the commissural stigmas reported by Tiagi forOpuntiaandMammillaria.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1964.tb06677.x

出版商:Wiley    

年代:1964

数据来源: WILEY

摘要:

Apical organization and the ontogeny of leaves of the ‘Hawkeye’ variety of soybean plants were examined. The initial region of the shoot apex consisted of a corpus and a 2‐layered tunica. Cells of the inner tunica layer were responsible for the initiation and development of leaves and stipules which were not significantly affected by foliar applications of a 50 mg/liter aqueous solution of gibberellic acid (GA). Initiation of leaves and stipules was simultaneous, but the early growth of the latter was more rapid. At the sixth or seventh node, the growth of the leaf primordia surpassed that of the stipules. There was meristematic activity in the stipular primordia to about the fifth node after which growth continued by cell enlargement. Stipels were initiated in the subepidermal layer of cells of the fourth leaf primordium, and development was completed at the eighth or ninth node. Gibberellic acid did not affect the size or shape of the stipels. Chlorosis of leaves and a reduction in size of the leaflets was apparent in GA‐treated plants. Terminal leaflets of treated plants had a slightly thinner lamina, smaller cells in the palisade layer and a greater amount of intercellular space. Increased cell elongation caused an early elongation of the internodes of the treated plants. Reduction of cell diameter resulted in a reduction in diameter of stems in GA‐treated plants. In response to GA, more lignified xylem parenchyma was produced, and partial collapse of relatively thin‐walled vessel elements and tracheids occurred. The extension of axillary shoots of GA‐treated plants was delayed temporarily, but once their extension began, they quickly surpassed the growth of the axillary shoots of untreated plants. Cell elongation was a major factor in the rapid extension of axillary shoots of treated plants. Anthesis was delayed and the number of pods per plant reduced in treated plants grown in long days. Only axillary flowers developed on treated and untreated plants grown in long days; however, the shoot apex of treated and untreated plants became floral in short days. The transition from the vegetative to the reproductive phase was delayed in treated plants.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1964.tb06678.x

出版商:Wiley    

年代:1964

数据来源: WILEY

摘要:

The respiratory pattern of broccoli bud clusters treated with N6‐benzyladenine at harvest or at daily intervals thereafter was similar to that of at‐harvest‐treated broccoli. The treatment effect did not diminish with time but was conditioned by the degree of physiological degeneration of the tissue prior to treatment. Respiration quotients indicated that the rate of oxidative decarboxylation and phosphorylation was reduced in tissues treated with N6‐benzyladenine. Higher organic phosphorus content was observed in treated tissue, and 2,4‐dinitrophenol overcame the N6‐benzyladenine‐induced respiration inhibition. It is suggested that the mode of action of phytokinins on respiration and senescence inhibition was due to a conservation of adenosine triphosphate in treated tissue.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1964.tb06679.x

出版商:Wiley    

年代:1964

数据来源: WILEY

摘要:

The incidence of flavonoids and phenolic acids substantiates the reclassification of a number of diploid taxa formerly considered as varieties of the tetraploid species,L. corniculatus.Whereas leaves ofL. corniculatuscontained leucodelphinidin, quercetin, leucocyanidin, kaempferol,p‐coumaric acid and ferulic acid, those of the diploid species,L. alpinus, L. japonicus, L. kryloviiandL. schoelleri,lacked leucodelphinidin but contained sinapic acid which was rarely found in leaves ofL. corniculatus.The leaves ofL. filicauliscontained the same compounds as those of the aforementioned diploid species but lacked sinapic acid.Lotus tenuisandL. borbasiidiffered most fromL. corniculatusin that their leaves possessed only kaempferol and ferulic acid. The morphological polymorphism evident in plants ofL. corniculatuswas not reflected in the flavonoid and phenolic acid content of this species. The data obtained lend support for the hypothesis of an allotetraploid origin forL. corniculatus.The phenolic content of the leaves of interspecific hybrids between diploid species was a summation of the phenolic residues found in the parental species. The same is true of the plants of an F2population of a cross betweenL. japonicusandL. filicaulis.The results indicate that phenolic compounds in the leaves ofLotusare inherited in a dominant fashion and that they may be used as species characteristics in systematic studies.Lotus caucasicushas been determined to be a tetraploid species with 24 somatic chromosomes.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1964.tb06680.x

出版商:Wiley    

年代:1964

数据来源: WILEY

摘要:

Chromatography of fungal enzyme mixtures on cellulose phosphate columns using pH‐gradient clution was followed by analysis of the separated fractions for polygalacturonase, maceration of killed potato tuber slices, and, in some instances, for pectin transeliminase and cellulase. The peaks of maceration activity coincided with those of endo‐polygalacturonase and pectin transeliminase. The latter was confirmed by further separation on DEAE‐cellulose. Exo‐polygalacturonase appeared not to macerate, and no indication was obtained of maceration by several other polysaccharases known to be present, although they might be demonstrable in the absence of polygalacturonase. These results strongly suggest that the middle lamella of the cell walls of this tissue consist essentially of pectinate (partly esterified polygalacturonate).

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1964.tb06681.x

出版商:Wiley    

年代:1964

数据来源: WILEY

摘要:

Microscopic examination of apple leaves infected by biochemical mutants ofVenturia inaequalisshowed that all mutants had penetrated the cuticle and had established themselves in the characteristic subcuticular position without an additional source of their required substances from outside the host. Those mutants that were fully as pathogenic as the wild type developed in vivo comparably to it, but those that were nonpathogenic made very limited growth and, with the exception of 1 requiring choline, failed to develop sufficiently to sporulate. However, the nonpathogenic mutants, with the exception of 1 requiring adenine, grew and sporulated in vivo when their required substances were applied to the surface of the inoculated leaves.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1964.tb06682.x

出版商:Wiley    

年代:1964

数据来源: WILEY