摘要:

AbstractThe influence Na, K, Rb or Cs may have when accompanying one of these elements applied foliarly to bean plants has bean studied under controlled environmental conditions. No competition was found in the speed of initial penetration from the outer leaf surface to the protoplasts of epidermal cells between any two of the cations considered separately. The magnitude of penetration of Na, Rb or Cs. Retention in the treated area showed competition among the elements, Na being held more strongly when accompanied by Cs, Rb or K in that order. Presence of another cation influenced retention differently. Transport of Na was faster than of either K, Rb or Cs when applied together. K and Rb were transported simultaneously at equal rates, and either more than Cs. Total quantities transported were influenced differently by the various cations present and in turn determined the total quantities taken up by the plants.

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1970.tb06484.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractAn intracellular, inducible β‐galactosidase [EC 3.2.1.23] was partially purified fromVerticillium albo‐atrum. The activity was associated with a particle of about one million molecular weight and required polyhydroxyl compounds for stabilization and activation. It was inhibited by various sulfhydryl inhibitors and EDTA. The latter inhibition could be overcome by adding Mn2+to reaction mixtures. The β‐ galactoside (ONPG) activity toward lactose (apparent Km= 0.08M) ando‐nitrophenyl‐β‐D‐galactoside (ONPG) (apparent Km= 2×10‐23M) purified in parallel. Lactose competitively inhibited the degradation of ONPG with a Kiof 0.1M. When activated by glycerol, the enzyme produced not only glucose and galactose from lactose, but also other unidentified products, perhaps by

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1970.tb06485.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractPlants of a pure line variety, G 24, ofCicer arietinumL. were grown in sand culture. After an initial dose of a complete nutrient solution, a nitrogen free nutrient solution was supplied to the sand at intervals and a standard rhizobial culture was added twice. The plants were treated with two concentrations of ascorbic acid (20 mg/l and 100 mg/l) through the rooting medium. At suitable intervals two pots from each treatment were sampled. Observations were made regarding the earliest initiation of nodulation, the number, weight and colour of nodules and the nitrogen content of different plant organs under various treatments.Ascorbic acid (AA) treatments considerably enhanced nodule initiation. AA was found to increase the number and the fresh and dry weights of nodules tremendously and maximally under both concentrations used. The nodules were, on the whole, more pink under AA treatments and their greening was considerably delayed thus increasing their functional span. The nitrogen content of AA‐treated plants was over 2.5 times that in the control. This increase in nitrogen content fully reflected itself in growth by an increase in the weight of all plant organs. Treatment with 20 mg/l AA stands out prominently above all others in this respect. Pod formation started earlier and the pod and seed weights were also much higher in the AA treatments than in the control. Treatment with 20 mg/l AA was on the whole more promotive than that with 100 mg/l.The enhancement in the nodulation and the functional efficiency of nodules by AA treatments has been attributed to the capacity of AA to increase the loci and rates of cell division by promoting nucleic acid and protein synthesis and its action as a powerful electron donor. The results show that nodulation is yet another phenomenon wherein AA plays the role of an important hormon

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1970.tb06486.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractSeed germination was totally inhibited by high (0.1N) concentrations of potassium or ammonium salts. Partial inhibition of germination occurred with low (<0.01N) concentrations of ammonium salts, but low concentrations of potassium salts did not affect germination. Except with extreme salt or ammonium injury, the inhibition of germination was at least partially reversible. Respiration of germinating seeds was inhibited by both species of salts. Seedling development was severely impaired by ammonium salts, but not by potassium salts.

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1970.tb06487.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractUptake of micronutrient zinc by intact leaves, enzymically isolated leaf cells, leaf disks, excised roots, and stem‐callus tissue of two field bean cultivars 'Saginaw’ and ‘Sanilac’) was studied using radio‐isotope tracer technique. Radio‐phosphorus absorption by these tissues was also followed under comparable experimental conditions. A rapid absorption of the micronutrient and strong dependency on external zinc concentration and pH were revealed. Absorption of zinc was not inhibited by respiratory inhibitors (dinitrophenol, azide, cyanide, and amytal), and was not light or temperature dependent. Q10values for zinc uptake ranged between 1 and 1.2. Uptake of phosphate, on the other hand, was temperature and light dependent and drastically reduced by the presence of metabolic inhibitors.Differences in responses to respiratory inhibitors, temperature, pH, light and darkness, and kinetic data, strongly suggest that zinc uptake in bean tissues occurs primarily by a passive mechanism, involving possibly a physical or physiochemical binding of the micronutrient ions to the cell wall and free space components, and a passive diffusion into the interior

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1970.tb06488.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractPyrocatechol (PC), 10‐2M, was applied to the foliage of mature plants of sugar beet (Beta vulgarisL.). Its effect on the activity of nitrate reductase, transaminase, invertase, phosphatases, sucrose synthetase, sucrose phosphate synthetase, and UDPG‐pyrophosphorylase were determined 7, 14, and 21 days after treatment. Significant reductions in the activity of nitrate reductase, transaminase, invertase, and phosphatases (including phenyl phosphatase, glucose‐1‐, glucose‐6‐, fructose‐6‐phosphatase, and adenosine triphosphatase) in the treated plants occurred. On the other hand, activities of the enzymes of sucrose biosynthesis, uridine, diphosphate glucose pyrophosphorylase (UDPG‐pyrophosphorylase), sucrose synthetase, and sucrose phosphate synthetase were significantly stimulated by the application of pyrocatechol. The results suggest that the growth inhibition following the application of PC to sugar beet plants may stem in part from an amino acid stress resulting from a PC‐induced decrement in nitrate reductase and transaminase activity. Its application also creates an enzymatic condition favorable for sucrose biosy

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1970.tb06489.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractA significant depression of callus growth resulted from low concentrations of abscisic acid (ABA) added to the medium recommended by Linsmaier and Skoog. Low concentrations also decreased the chlorogenic acid and lignin content of the callus, and generally decreased amounts of scopolin and scopoletin in the tissue. Gibberellic acid (GA3) stimulated callus growth in a low concentration (0.1 mg/1) and inhibited growth at a high concentration (10.0 mg/1). Both levels of GA3increased scopoletin accumulation in tobacco callus. A high concentration of GA3increased the accumulation of scopolin and chlorogenic acids, whereas a low concentration decreased the amounts of these two phenolic compounds. In comparison with the control, lignin synthesis was stimulated by a low GA3concentration, but a high GA3concentration did not have a significant effect. Both low and high concentrations of GA3overcame ABA inhibition of growth and lignin synthesis, and partially reversed ABA inhibition of scopoletin production. However, GA3did not reverse the inhibitory effect of ABA on scopolin production. The low concentration of GA3overcame the inhibition of chlorogenic acid production resulting from a 0.01 mg/1 concentration of ABA, but this was the only reversal of chlorogenic acid inhibition resulting from addition of GA3to the medium.

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1970.tb06490.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractThe regulative systems of auxins, gibberellin‐like substances and their inhibitors in citrus fruit were studied. Masking caused by a high content of inhibitors was eliminated by using a refined method of solvent partition. Considerable amounts of auxins and gibberellin‐like substances were detected in all stages of fruit development. The auxin system of the citrus fruit is highly complex and consists of various elements which undergo dynamic changes throughout the growth period. The identity of the auxins was studied using IAA‐2‐14C, and 88% of the radioactivity specifically migrated into the etheric pH 6.0 fraction. Although the prominent zones of promotion do not coincide with IAA, it can be concluded that the auxin promoters are probably not the “citrus auxin”. Abscisic acid‐like inhibitors were found to accumulate in the external layers of the fruit, increasing in content as

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1970.tb06491.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractWe have studied the action of different zinc concentrations (10, 50 and 100 mg/l) on the germination ofThlaspiseeds and on the seedlings obtained from them when grown on water containing the same zinc concentrations.It appears that the 10 mg/l zinc concentration enhances slightly the percentage germination and that the 50 mg/l concentration is the optimum one for the growth of the seedlings. Therefore it seems that the normal growth of a plant growing on a “calamine soil” demands a given quantity of zinc, the optimum being in the neighbourhood of 50 m

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1970.tb06492.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

AbstractIon transport and ion selectivity in bean hypocotyl slices were investigated. The transport mechanism is practically independent of temperature and in short term experiments appears to be non‐metabolic.Selectivity may be attributed either to specific adsorption sites or to the properties of the diffusion barrier. The fact that with a physical transport mechanism selectivity is observed only under physiological temperature conditions hints that a flexible barrier (plasmalemma?) rather than fixed adsorption sites should be regarded as governing the proces

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1970.tb06493.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY