摘要:

AbstractABA and gibberellin‐like substances were extracted from roots, shoots, and leaves of most dwarfing M9, semi‐dwarfing MM 106, and least dwarfing MM111 apple rootstock plants. Among tissues, the roots contained the largest and the shoots the smallest amounts of all the phytohormones studied. Plants of M9 contained the highest and MM111 the lowest ABA‐like substances in all tissues tested. Gibberellin4+7‐like compounds were at the highest levels in the roots of MM111 and lowest in the roots of M9, whereas GA3‐like substance was in the reverse order. All three gibberellin‐like compounds were highest in the shoots and leaves of MM111 and lowest in the respective tissues of M9 clone. Role of these phytohormones in the dwarfing mechanism i

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1977.tb04062.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractYoung shoot tips of species and hybrids from thePrunussectioneucerasuscontain catechin, epicatechin and flavolans (oligomeric flavans including biflavans).Prunus aviumshoot segments, 2 mm in length, were excised from the elongating zone of growing shoots and culturedin vitroon a liquid Murashige and Skoog medium containing indolyl‐3‐acetic acid and benzyl adenine. Supplementation of the same medium with (+)‐catechin and epicatechin resulted in apparent promotion of callus growth. This effect was greater under long day conditions than under continuous

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1977.tb04063.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractTryptophan synthase in Phycomyces blakesleeanus. Part II: Activity of tryptophan synthase in Phycomyces blakesleeanus depending on the light and the content of zinc ions in the culture mediumFive‐day‐old cultures ofPhycomyces blakesleeanusshow notice‐able differences in the phenotype, depending on the culture conditions (permanent light, permanent dark, zinc deficiency, zinc sufficiency) and related to the distribution of tryptophan synthase activity between mycelium and sporangiophores. Permanent light and the presence of zinc ions in the medium during culturing have an antagonistic influence on the tryptophan synthase. The activity of the enzyme is being reduced in the sporangiophores and increased in the mycelium by the influence of light, while zinc ions in the culture medium increase the activity in the sporangiophores at simultaneous reduction in the mycelium.The importance of tryptophan synthase and tryptophan for the development of the fungus in relation to the metabolism of indole acetic acid is disc

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1977.tb04064.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractFatty acid methyl esters ofPolytrichum communespore triglyceride and mono‐ and diglycosyl diglyceride fractions were analysed by glass capillary column gas chromatography provided with a precolumn system. The composition of the fatty acids in the lipid fractions differed only quantitatively: the diglycosyl diglyceride fraction was characterized by a high content of C 18: 3ω3 (67.7%), and the triglyceride and monoglycosyl diglyceride fractions by about 35%. The monoglycosyl diglyceride fraction contained a high proportion of C 14: 0 (18.4%). In all fractions the content of polyunsaturated C 20 acids was low, ranging from trace amounts to 4.

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1977.tb04065.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractRibonuclease has been extracted from buds of bird‐cherry (Prunus padusL.) by a three‐step method. In step 1 ribonuclease was extracted from the homogenized tissue at pH6. In step 2 the tissue residue from (1) was extracted at pH7. In step 3 the tissue residue from (2) was extracted with a buffer of pH8.5 and containing 0.7MKCl. The ribonuclease from step 1 and 2 is named soluble and that from step 3 bound ribonuclease. The activity of the soluble ribonuclease was very low in October and increased slowly until March. When the buds sprouted in April the activity of this fraction rose rapidly. The activity of the bound ribonuclease was rather high in October and increased continuously from autumn to spring. RNA accumulated slowly between autumn and spring. The change in activity of the two ribonuclease fractions is discussed in relation to developm

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1977.tb04066.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractCellular Multiplication and Lipid Synthesis during in vitro Culture of Taphrina insititiae and Taphrina pruni, Parasites of Prunus domestica.TwoTaphrinaspecies were grown on “yeast extract/glucose” and harvested at regular intervals. Their growth was estimated by dry mycelial weight and cell nitrogen. Lipids were recovered and measured by weighing. Phospholipids, which form the major portion of polar lipids, were measured by phosphorus assay.Lipidic and nitrogenous products were studied with regard to the evolution of the cultures during the phase of active growth. The cells accumulated fats, but during the phase of autolysis, fat content decreased. Production of nitrogenous components was maximal during the autolytic phase. Phospholipids varied as nitrogenous and inversely to neutral lipids. There was apparently an antagonism between nitrogen assimilation and synthesis of neutral lipids. Different functions of neutral and polar lipids may be involved, so that the former act as a reserve material and the latter represent an essential structural cell constituent.Fatty acids were analysed by gas liquid chromatography at various culture periods. Fatty acids from polar as well as those from neutral lipids exhibited great variations with regard to culture evolution. The ratio insaturated/saturated fatty acids is greater in polar lipids than in neutral lipids. These variations are discussed with regard to their consequences for the function of cell membra

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1977.tb04067.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractSeveral structural changes in cotton (Gossypium hirsutumL.) leaves attendant on development under conditions of water deficit were examined. Cell size was less and cell wall thickness greater in the leaves of stressed plants than in leaves of well‐watered plants. A short review of the literature suggested that the lesser cell size is a fairly general observation and that it may contribute to plant resistance to moisture stress.A simple model is developed to investigate the influence of the reduction of cell size on cellular water relations. The predictions which can be drawn from simulations with this model are that smaller cells should maintain turgor to lower values of water potential than larger cells. Rather large changes in cell water relations are predicted for small changes in cell size. These effects are related principally to the changing proportion of cell water which resides in the cell wall and is external to the plasmalemma and the osmotic adjustment system. This prediction is in agreement with several observerations on the behavior of stress‐hardened plants and supports the hypothesis that plants or tissues with the smaller cell size will be more tolerant of low water potent

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1977.tb04068.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractResponses of sevenPhaseolusgenotypes to the four auxins picloram, 2,4‐D, NAA and 1AA, in tissue cultures, were examined. Callus growth was promoted by picloram and the range of effective concentrations for most genotypes was broad. The auxin 2,4‐D also enhanced callus growth, but the range of optimal concentrations was markedly narrower than that of picloram. NAA when supplied at relatively high concentrations gave good growth. IAA was ineffective in supporting callus growth. The differences in 2,4‐D concentrations required for optimal growth and the differential responses to low concentrations (0.04–1.25 μM) of picloram between several genotypes tested were large. These genotypic variations in auxin responses were repeatable and may thus reflect genetic dif

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1977.tb04069.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractThe rooting activity of water extracts of cuttings of chestnut (Castanea sativaMill.) and willow (Salix viminalisL.) was studied throughout the year by the bean rooting test. The chestnut extract nullified the rooting activity of 10−5MIAA, but on the whole it did not modify the rooting pattern of the bean cuttings. The willow extract increased rooting and showed a rhythm in the content of endogenous growth substances. IAA was found at the time when the extract showed the strongest rooting activity. The extract from willow contained two synergistic root‐promoting fractions with theRf's of 0.0–0.2 and 0.6–0.8 in isopropanol: ammonia: water. The latter one promoted rooting without added IAA. In this fraction a high amount of catechol was detected. No clear correlation was found between the ability to induce roots and the total phenol content in the two

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1977.tb04070.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY

摘要:

AbstractDemonstration of a regulatory effect of exogenous proline on the glycolate cycle inNicotiana tabacumcv. Xanthi n.c.An exogenous proline supply in the light provokes an increase in free glycine concentration in apical tissues or leaf disks of vegetativeNicotiana tabacumcv. Xanthi n.c. The same phenomenon does not occur in the equivalent tissues of tobacco plants after floral induction, these being naturally rich in proline. Under different environmental conditions (light, dark, varying concentrations of CO2and O2), the exogenous proline appears to modify one or more reactions of the glycolate pathway.

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1977.tb04071.x

出版商:Blackwell Publishing Ltd    

年代:1977

数据来源: WILEY