摘要:

AbstractThe aleurone grains of the peanut (Arachis hypogaea) have been fractionated into the globoidal and nongloboidal components by homogenization in 0.5Msucrose solution and differential centrifugation. The major components of the globoids are: protein, 35.1%; magnesium, 2.5%; potassium, 2.0%; myoinositol, 7.0%; total phosphorus, 7.4%; oxalic acid, 3.5%; and moisture, 8.6%. Small amounts of calcium (0.5%) and manganese (0.03%) are also present. Of the total phosphorus about 97% is present as organic phosphorus of which phytic acid (myoinositol hexaphosphoric acid) constitutes the major portion with only 0.1% orthophosphate and traces of lower phosphates of myoinositol. The globoidal fraction accounts for about 50% of the total magnesium, manganese, phytic acid, oxalic acid, and for 13% of the potassium and 80% of the calcium present in the aleurone grains. The remainder of these components are present in the matrix of the aleurone grain. There seems to be a cation deficit in the globoids and a cation excess in the aleurone grains and soluble fraction. The nature of the missing cation in the globoid and the missing anion in the aleurone grain or in the soluble fraction was not determined, but thought to be protein.

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1975.tb03754.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractIt has been shown that addition of phosphate to phosphate deficient yeast gives rise to an immediate increase in the rate of Na+uptake and an immediate decrease in the rate of Rb+uptake. In addition, phosphate uptake is enhanced specifically by Na ions presumably by a process with a very high affinity for phosphate with aKmof about 2 × 10−6Mat pH 7.2, whereas theKmfor phosphate uptake of the Na+independent process amounts to 1.3 × 10

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1975.tb03755.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractChanges in photosynthesis and transpiration of a potted birch seedling were simultaneously followed in the field using two infrared gas analyzers. Wet and dry temperature measurements alone explained 81% of the variation in the transpiration rate when the plant was not suffering from water deficit. During drought and the period after the water balance had been restored, net photosynthesis decreased more distinctly than transpiration. This result was in accordance with our previous results on the after‐effects of water deficit on photosynthesis, and it was also interpreted as evidence for at least partly separate control mechanisms for photosynthesis and transpiratio

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1975.tb03756.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractSeedling growth, protein, soluble amino nitrogen, and proteolytic activity of serido beans (Vigna sinensis) were studied during the first 6 days of germination. Cotyledon dry weight decreased constantly with germination time, reaching at the 6th day 27% of the weight it had at day 0. Embryo‐axis dry weight increased during the same period, amounting to 79% of the total weight of the seedling at the 6th day of germination. Cotyledon proteins increased slightly during the 1st day of germination and then decreased until the end of the experimental period. Cotyledonary soluble amino nitrogen stayed constant for the 1st day of germination, increased up to the 3rd day, and then fell steadily until the 5th day. Embryo‐axis soluble amino nitrogen followed the same pattern as the embryo‐axis proteins, that is, a slight increase during the first 3 days, a pronounced increase from the 3rd to the 5th, and a leveling off from this day on. Proteolytic activity was studied at pH 3.5 and pH 6.0. Both proteases increased in activity during the first 3 days of germination, at which point they reached their maximum activities. From this day on their activities fell continuously, reaching on the 6th day values slightly higher than those of day 0. These observations appear to indicate that contrary to pea cotyledon proteases, serido bean protesaes are intimately associated with reserve protein degrad

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1975.tb03757.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractBoth dark and red light germination of lettuce seeds (cv. “Maikönig”) as well as their root and hypocotol elongation were inhibited when the seeds were sown in petri dishes together with a few seeds ofHeracleum laciniatumHorn. This inhibition was not significantly counteracted by the presence of gibberellic acid (GA3) or/and 6‐benzylaminopurine (BA). However, a large proportion of the lettuce seeds germinated abnormally (only cotyledons emerged) when treated with BA in the presence of Heracleum seeds. GA3had alone no significant effect on abnormal germination, but it counteracted the effect of BA to some extent.The inhibitory effect of Heracleum seeds gradually disappeared during a moist incubation period of one to seven days in darkness at 25°C.When lettuce seeds were pre‐incubated together with Heracleum seeds for one to five days the remaining, non‐germinated lettuce seeds had lost their ability for subsequent germination in darkness in distilled water. This induced dark dormancy was to a great extent broken by red light, but not by GA3or/and BA.H. laciniatum seeds inhibited the germination ofSalix pentandraseeds and to some extent also the germination of radish but had no effect on the germinatio

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1975.tb03758.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractAn experiment was carried out to study the effect of reduced growth on the photosynthetic rate of leaves in cotton (Gossypium hirsutum). It was planned to reduce growth by the continuous removal of axillary buds.The results show that debudding did not reduce the growth of plants but only altered the distribution pattern of assimilates. The shoot weight of the control and debudded plants was not significantly different. However, debudding prevented reproductive development in the debudded plants. Comparison of the photosynthetic rates of the control and debudded plants indicate that reproductive development did not affect the photosynthesis of young fully expanded leaves but slightly increased the rate of decline in photosynthesis during their ageing.

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1975.tb03759.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractThe effect of indol‐3yl‐acetic acid on root formation, accumulation of 80% ethanol‐soluble sugars and basipetal transport of14C‐labelled assimilates has been investigated inPhaseolus vulgaris(cv. Canadian Wonder) hypocotyl cuttings. The removal of leaves reduced root formation in the hypocotyl, while excision of the apical bud was less detrimental. The expression of the IAA effect in inducing more roots was dependent on the area of leaves, and was found to be better when all leaves were present. Sugars accumulated slowly at the base of cuttings during a four‐day period after excision, and IAA greatly enhanced this accumulation. By comparing sugar content at the base of green and starved cuttings it was established that IAA greatly increased it concurrently with root formation.IAA applied in solution to the hypocotyl greatly enhanced the basipetal transport of14C‐labelled assimilates and their accumulation at the hypocotyl during a 24‐h period. The IAA‐induced accumulation was found to be connected with a greater mobilization of labelled assimilates from upper parts of the cutting. Experiments involving pretreatment with IAA and transport in cuttings already possessing root primordia, suggest a dual effect of IAA: (I) a direct effect on transport, and (2) an increase in the root‐“sink”. It is concluded that both may be operating in inducing basipetal accumulation of labelled assimilates. It is suggested that one of the roles of IAA in promoting rooting of cuttings is to increase sugar availability at the s

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1975.tb03760.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractAxenic crown gall tumor callus (fromVinca roseaL.) which is known to synthesize its own auxin is able to convert exogenous14C‐indole or tryptamine to indoleacetic acid [5.4 and 10 × 10−6μmol × h−1× (g fr wt)−1respectively], but little or no3H‐tryptophan is converted [less than 6.4 × 10−8×μmol

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1975.tb03761.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractLipid peroxidation and decrease in chlorophyll‐aand chlorophyll‐bcontent inScenedesmuscells was followed in the course of time. Addition of diquat to the algae in the light causes lipid peroxidation and a decrease in chlorophyll content. This decrease is mainly due to chlorophyll‐a, the concentration of chlorophyll‐bremains more or less constant during the experiment. In the presence of N′‐(3,4‐dichlorophenyl)‐NN‐dimethylurea (DCMU), of cysteine, or during nitrogen‐flushing of the algal suspension, the lipid peroxidation caused by diquat is strongly suppressed. The decrease in chlorophyll‐acontent caused by diquat is somewhat smaller in the presence of DCMU or during nitrogen‐flushing than with diquat alone, but is not influenced by cysteine. The chemical antioxidant butylated hydroxytoluene does not affect lipid peroxidation and chlorophyll destr

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1975.tb03762.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractThe respiratory rate increased in two phases during early stages of callus formation in carrot (Daucus carota)‐root phloem slices culturedin vitro, showing separate peaks at about 24 and 96 h of culture. In the first phase (within 24 h of culture), the activities of phosphoglucose isomerase, phosphofructokinase and succinate dehydrogenase did not increase, but active syntheses of RNA and protein, indicated by experiments with incorporation of [14C]‐uracil and ‐leucine, resulted in an active turnover of ATP, to which the first increase in the respiratory rate may be attributable. On the other hand, the activity of phosphoribosylpyrophosphate synthetase, an enzyme related to nucleic acid synthesis, increased in the first 24 h of culture. In the second phase (24–96 h of culture), the activities of the respiratory enzymes investigated increased. This increase was repressed by cycloheximide, indicatingde novosyntheses of the respiratory enzymes during this time, which may result in an enlargement of the respiratory capacity, to which the second increase in respiration may be mainly attributable. In the first phase, exogenous supplied 2,4‐dichlorophenoxyacetic acid had little or no effect on the respiratory rate and the activities of the respiratory enzymes, but it enhanced synthesis of RNA and the activity of phosphoribosylpyrophosphate synthetase. In the second phase, it increased all the activities of enzymes investigated as well as the respiratory rate and RNA

ISSN:0031-9317    

DOI:10.1111/j.1399-3054.1975.tb03763.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY