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1.
M. L. Centeno B. Fernández I. Feito A. Rodríguez 《Journal of Plant Growth Regulation》1999,18(2):81-88
1-Naphthaleneacetic acid (NAA) and 6-benzyladenine (BA) were required for in vitro callus formation at the basal edge of
kiwifruit (Actinidia deliciosa [A. Chev] Liang and Ferguson, cv. Hayward) petioles. The uptake, metabolism, and concentration of NAA and indole-3-acetic
acid (IAA) content were examined in the explants during the callus initiation period. After 1, 6, 12, 24, 48, and 96 h of
culture in the presence of [H3]NAA, petioles were divided into apical, middle, and basal portions and analyzed. Except for a high IAA level measured at
12 h, IAA content decreased in tissues during a culture period of 96 h. NAA uptake was higher in petiolar edges than in the
middle portion, and NAA was rapidly conjugated with sugars and aspartic acid inside the tissues. The amide conjugation was
triggered in apical and basal portions from 12 h and in the middle part from 48 h, with α-naphthylacetylaspartic acid being
the major metabolite. Free-NAA concentration in cultured petioles achieved an equilibrium with the exogenously applied NAA
(0.27 μm) from 12 h, and it remained constant thereafter. The relationships between the role attributed to NAA and BA in the initiation
and the maintenance of disorganized growth of callus in kiwifruit cultures are discussed.
Received December 21, 1998; accepted July 20, 1999 相似文献
2.
L. Wijayanti S. Fujioka M. Kobayashi A. Sakurai 《Journal of Plant Growth Regulation》1997,16(2):115-119
The involvement of abscisic acid (ABA) and indole-3-acetic acid (IAA) in the regulation of flowering of Pharbitis nil was investigated through exogenous applications and analyses of endogenous levels. Both hormones inhibited the flowering
of P. nil when they were applied before or after a single 15-h dark treatment. The inhibitory effect of ABA and IAA was significant
when they were applied before the dark treatment, and the application to plumules was more effective than that to cotyledons.
In all applications, the inhibitory effect of IAA was stronger than that of ABA. Endogenous levels of ABA and IAA in the plumules
were compared between flower-inductive (15-h dark treatment) and noninductive (continuous light) light conditions. There was
no significant difference in the ABA level between light and dark conditions, whereas the level of IAA was decreased by the
dark treatment. These results suggest that biosynthesis and/or catabolism of IAA is affected by the light treatment and therefore
may be involved in the regulation of early flowering processes in the apex. The inhibitory effects of ABA and IAA were reversed
by an application of gibberellin A3, indicating that gibberellin A3 counteracts the flowering processes affected by ABA and IAA. Application of aminoethoxyvinylglycine restored the flowering
response inhibited by IAA, which suggests the possibility that the inhibitory effect of IAA is the result of enhanced ethylene
biosynthesis.
Received November 22, 1996; accepted February 17, 1997 相似文献
3.
B. Hossain N. Hirata Y. Nagatomo R. Akashi H. Takaki 《Journal of Plant Growth Regulation》1997,16(4):239-243
A high zinc concentration of 520 μm, approximately 100 times that used most often in standard plant tissue culture media, was found to be superior in liquid
callus cultures of japonica rice, increasing growth to 146% compared with standard N6 medium. At the same time, the internal
zinc concentration increased 40 times in fast growing cells; soluble protein doubled, and free amino acids decreased. Under
zinc-free conditions the cultures slowed in growth, and several free amino acids such as aspartic acid, glutamic acid, asparagine,
and glutamine accumulated. We suggest that zinc acts as a direct regulatory factor in inducing auxin activity, but not auxin
levels, making high internal zinc accumulation mandatory if high auxin concentrations are required as in rice callus cultures.
Received July 16, 1997; accepted September 22, 1997 相似文献
4.
H. R. Irving G. Dyson R. McConchie R. W. Parish C. A. Gehring 《Journal of Plant Growth Regulation》1999,18(2):93-100
The effects of jasmonic acid (JA) on elongation growth of coleoptile segments from etiolated maize (Zea mays L.) were investigated in the presence and absence of auxin. When supplied alone, at physiological concentrations (10−9, 10−8, and 10−5
m), JA (or methyl-JA) inhibited growth. JA at a similar range of concentrations also inhibited auxin-induced elongation growth.
To determine whether this effect on growth depended on endogenous abscisic acid (ABA), we grew maize coleoptiles in the presence
of norflurazon (an inhibitor of carotenoid biosynthesis) that results in reduced endogenous ABA levels. Growth of etiolated
coleoptile segments from these plants was inhibited by JA (or methyl-JA) in both the absence and presence of auxin. Previously,
we have observed a correlation between elongation growth and cytosolic pH (pHi), in which auxin lowers pHi, and growth inhibitors such as ABA raise pHi. We examined the effect of low concentrations of methyl-JA on pHi with dual emission dye, carboxy seminaphthorhodafluor-1, and confocal microscopy. To confirm these studies, we also used
in vivo 31P NMR spectrometry to ascertain the changes in pHi after addition of jasmonate to maize coleoptiles. Coleoptiles grown in either the absence or presence of norflurazon responded
to methyl-JA or JA by increases in pHi of approximately 0.2 pH unit. This response occurs over a period of 15–20 min and appears to be independent of endogenous
ABA. This alkalization induced by JA is likely to form a permissive environment for JA signal transduction pathway(s).
Received February 5, 1999; accepted August 25, 1999 相似文献
5.
M. J. Montague 《Journal of Plant Growth Regulation》1997,16(1):11-19
Segments can be cut from the peducular-1 internode of oat (Avena sativa L.) shoots so as to contain the graviresponsive, auxin-sensitive leaf sheath pulvinus, and the gibberellin-sensitive internodal
tissue. These two growth-capable tissues were used to study the effects and interactions of jasmonic acid (JA) and abscisic
acid (ABA) in regulating cell elongation. When supplied alone at physiologic concentrations (10−5, 10−4
m), JA promoted growth and cell wall synthesis in the internodal tissue, whereas by itself, ABA inhibited internodal elongation
and even inhibited JA-promoted growth. When gibberellic acid (GA3) was used to stimulate internodal elongation, JA and ABA caused similar levels of inhibition and, at certain concentrations,
were synergistic. Inhibition by ABA was initiated several hours earlier than inhibition by JA, and only the ABA effect could
be partially overcome by 10−3
m aminoethoxyvinylglycine. Both JA and ABA inhibited elongation of pulvinar tissue that was induced to grow by gravistimulus
or auxin, although here JA was more potent than ABA at equimolar concentrations. When 10−5
m fusicoccin was used as a general nonphysiologic growth stimulus, JA had no effect on the internode but inhibited the pulvinus,
whereas ABA had no effect on the pulvinus but inhibited the internode. These results provide strong physiologic evidence that
JA and ABA act by different mechanisms in the regulation of elongation, at least in this representative grass.
Received May 28, 1996; accepted November 7, 1996 相似文献
6.
The roles of auxin and cytokinin in cell cycle reactivation were studied during the first 48 h of culture of mesophyll protoplasts
of Nicotiana tabacum. Using hormone delay and withdrawal studies we found that auxin was required by 0–4 h of culture, whereas cytokinin was not
required until hour 10–12, which is 6–10 h before S phase. Cycloheximide blocks division, indicating that protein synthesis
is required. In an effort to detect a molecular response to either hormone, we examined the expression of the cell cycle marker,
cdc2. Cdc2 expression was detected by 12 h of culture, coincident with the timing of the cytokinin requirement and well before the entry
into S. However, cdc2 was partially induced by either auxin or cytokinin alone, suggesting that cdc2 expression is not the primary target of either hormone. Our hormone delay experiments suggest that there are separate signal
transduction pathways leading from auxin and from cytokinin to reactivation of the cell cycle and that these pathways converge
before S. The underlying mechanisms for these distinct pathways remain to be elucidated.
Received November 4, 1997; accepted October 7, 1998 相似文献
7.
Guerrero JR Garrido G Acosta M Sánchez-Bravo J 《Journal of Plant Growth Regulation》1999,18(4):183-190
3H-IAA transport in excised sections of carnation cuttings was studied by using two receiver systems for recovery of transported
radioactivity: agar blocks (A) and wells containing a buffer solution (B). When receivers were periodically renewed, transport
continued for up to 8 h and ceased before 24 h. If receivers were not renewed, IAA transport decreased drastically due to
immobilization in the base of the sections. TIBA was as effective as NPA in inhibiting the basipetal transport irrespective
of the application site (the basal or the apical side of sections). The polarity of IAA transport was determined by measuring
the polar ratio (basipetal/acropetal) and the inhibition caused by TIBA or NPA. The polar ratio varied with receiver, whereas
the inhibition by TIBA or NPA was similar. Distribution of immobilized radioactivity along the sections after a transport
period of 24 h showed that the application of TIBA to the apical side or NPA to the basal side of sections, increased the
radioactivity in zones further from the application site, which agrees with a basipetal and acropetal movement of TIBA and
NPA, respectively. The existence of a slow acropetal movement of the inhibitor was confirmed by using 3H-NPA. From the results obtained, a methodological approach is proposed to measure the variations in polar auxin transport.
This method was used to investigate whether the variations in rooting observed during the cold storage of cuttings might be
related to changes in polar auxin transport. As the storage period increased, a decrease in intensity and polarity of auxin
transport occurred, which was accompanied by a delay in the formation and growth of adventitious roots, confirming the involvement
of polar auxin transport in supplying the auxin for rooting.
Received April 19, 1999; accepted December 2, 1999 相似文献
8.
A Possible Role for Jasmonic Acid in Adaptation of Barley Seedlings to Salinity Stress 总被引:6,自引:0,他引:6
T. D. Tsonev G. N. Lazova Z. G. Stoinova L. P. Popova 《Journal of Plant Growth Regulation》1998,17(3):153-159
The changes caused by NaCl salinity and jasmonic acid (JA) treatment (8 days) on growth and photosynthesis of barley plants
(Hordeum vulgare L., var. Alfa) have been studied. Gas exchange measurements and analysis of enzyme activities were used to study the reactions
of photosynthesis to salinity and JA. Both 100 mm NaCl and 25 μm JA treatment led to a noticeable decrease in both the initial slope of the curves representing net photosynthetic rate vs
intercellular CO2 concentration and the maximal rate of photosynthesis. The calculated values of the intercellular CO2 concentration, CO2 compensation point, and maximal carboxylating efficiency of ribulose-1,5-bisphosphate carboxylase support the suggestion
that biochemical factors are involved in the response of photosynthesis to JA and salinity stress. The activities of phosphoenolpyruvate
carboxylase and carbonic anhydrase increased more than twofold. Pretreatment with JA for 4 days before salinization diminished
the inhibitory effect of high salt concentration on the growth and photosynthesis. The results are discussed in terms of a
possible role of JA in increasing salinity tolerance of the barley plants.
Received September 8, 1997; accepted May 19, 1998 相似文献
9.
Greenhouse and growth chamber experiments were conducted to determine the effect of soil moisture and temperature on the
phytotoxicity in wild oat of imazamethabenz or fenoxaprop tank-mixed with certain additives or MCPA. The surfactants Agral
90 at 0.5% and Enhance at 0.5% increased imazamethabenz phytotoxicity under both moist and drought conditions. These surfactants
had no significant effect on fenoxaprop phytotoxicity regardless of the soil moisture regimes. Fenoxaprop activity was increased
by ammonium sulfate [(NH4)2SO4] at 1% but only under well watered conditions. Wild oat control with imazamethabenz was also slightly enhanced in a well
watered regime by the addition of sodium bisulfate (NaHSO4) at 0.13%. At high temperature (30/20°C) and low temperature (10/5°C), the phytotoxicity of imazamethabenz was increased
when tank-mixed with Agral 90 at 0.25% or NaHSO4 at 0.13% compared with that when imazamethabenz was applied alone, if soil moisture was adequate. There was no such increase
under conditions of drought and high temperature. (NH4)2SO4 at 1% did not significantly affect imazamethabenz performance irrespective of temperature/soil moisture conditions. The phytotoxicity
to wild oat of imazamethabenz or fenoxaprop was not changed by tank-mixing with MCPA isooctyl ester at 300 g a.i./ha, regardless
of soil moisture levels. The reduced fenoxaprop phytotoxicity in wild oat due to moisture stress was not readily alleviated
by the inclusion of selected additives or MCPA in the tank mixture.
Received May 10, 1996; accepted January 10, 1997 相似文献
10.
Puhui Ji Yongji Jiang Xiwang Tang Thanh Hung Nguyen Pengcheng Gao 《Soil & Sediment Contamination》2015,24(8):909-916
In this study, a pot experiment using Solanum nigrum L. grown in cadmium-contaminated soil was conducted in a greenhouse. Indole-3-acetic acid (IAA) was applied at three different concentrations (1 mg L?1, 10 mg L?1, and 100 mg L?1) to examine the effects on phytoremediation efficiency. According to the experimental results, IAA increased the shoot biomass of S. nigrum significantly, by 124% at the highest concentration used, and increased the Cd concentration in the shoot of S. nigrum by 16%. The Cd extraction amount from a single plant was increased by up to 158%, demonstrating potential practical application for remediation practice. 相似文献
11.
Involvement of Abscisic Acid in Mesocotyl Growth in Etiolated Seedlings of a Foxtail Millet Dwarf Mutant 总被引:1,自引:0,他引:1
Etiolated seedlings of foxtail millet (Setaria italica Beauv.) dwarf mutant CH84113 were treated with various concentrations of abscisic acid (ABA), mefluidide, mannitol, or polyethylene
glycol (PEG) 6000. It was found that these chemicals, at suitable concentrations, could increase mesocotyl length significantly,
whereas these chemicals at higher concentrations had an inhibitory effect. Endogenous levels of ABA in mesocotyl were measured
by enzyme-linked immunosorbent assay. It was found that endogenous ABA increased progressively in a chemical (ABA, mefluidide,
mannitol, or PEG 6000) concentration-dependent manner, indicating that the effects of these chemicals on mesocotyl growth
may be mediated by increased endogenous ABA levels. On the other hand, S-3307, an inhibitor of the oxidative reactions in
gibberellin (GA) biosynthesis, inhibited the elongation of mesocotyl significantly. When ABA and GA3 were applied simultaneously, the effect on mesocotyl growth was additive. These results imply that ABA and GA may control
different processes in the regulation of mesocotyl growth.
Received October 27, 1997; accepted May 11, 1998 相似文献
12.
Simultaneous measurements of respiration, ethylene production, and abscisic acid (ABA) concentrations, as well as the growth
parameters length, fresh weight (FW), and dry weight (DW) of olive (Olea europaea L. cv. Konservolia) inflorescence were carried out at short intervals (3–7 days) during the period from bud burst until the
3rd week after full bloom (AFB), when young fruit reached 8 mm in length. The axis of inflorescence elongated remarkably during
the 3rd week after bud burst (ABB), massive bract shedding occurred during the 4th week ABB, full bloom (FB) was observed
7 weeks ABB, and massive floral organ abscission 1 week AFB. The results showed a continuous increase in inflorescence FW
and DW from bud burst until 4 days before FB. Respiration rate, ethylene production, and levels of ABA were relatively high
during the first 3 weeks ABB. After this period, respiration and ethylene followed a similar pattern of changes, inversely
to that of ABA concentration. An accumulation of inflorescence ABA 6 and 4 days before FB was associated with the minimum
values of respiration and ethylene production on the same dates. The sharp decrease in the ABA concentration during FB and
3 days later was followed by a high rise in ethylene and an increase in respiration rate, which both rose further 1 week AFB.
The results suggest a possible correlation of ABA with the early stage of floral abscission, whereas ethylene production seems
to be correlated with the terminal separatory activity in olive inflorescence abscission processes.
Received May 28, 1998; accepted November 17, 1998 相似文献
13.
Potential Role of Abscisic Acid in Cotton Fiber and Ovule Development 总被引:11,自引:0,他引:11
Fibers and ovules of a cotton cultivar (Gossypium hirsutum L. Trambak-108) were analyzed for growth and free abscisic acid (ABA) content by indirect enzyme immunoassay. An inverse
correlation between fiber elongation and ABA content was observed. In the seed, accumulation of ABA was observed during secondary
thickening and the maturation phase. The potential role of ABA in fiber and seed development is discussed.
Received June 25, 1997; accepted October 15, 1997 相似文献
14.
Effects of Auxin Transport Inhibitors on Gibberellins in Pea 总被引:5,自引:0,他引:5
J. J. Ross 《Journal of Plant Growth Regulation》1998,17(3):141-146
The effects of the auxin transport inhibitors 2,3,5-triiodobenzoic acid (TIBA), 9-hydroxyfluorene-9-carboxylic acid (HFCA),
and 1-N-naphthylphthalamic acid (NPA) on gibberellins (GAs) in the garden pea (Pisum sativum L.) were studied. Application of these compounds to elongating internodes of intact wild type plants reduced markedly the
endogenous level of the bioactive gibberellin A1 (GA1) below the application site. Indole-3-acetic acid (IAA) levels were also reduced, as was internode elongation. The auxin
transport inhibitors did not affect the level of endogenous GA1 above the application site markedly, nor that of GA1 precursors above or below it. When plants were treated with [13C,3H]GA20, TIBA reduced dramatically the level of [13C,3H]GA1 recovered below the TIBA application site. The internodes treated with auxin transport inhibitors appeared to be still in
the phase where endogenous GA1 affects elongation, as indicated by the strong response to applied GA1 by internodes of a GA1-deficient line at the same stage of expansion. On the basis of the present results it is suggested that caution be exercised
when attributing the developmental effects of auxin transport inhibitors to changes in IAA level alone.
Received April 13, 1998; accepted April 14, 1998 相似文献
15.
The effects of pot size, timing of the application of paclobutrazol (PTZ) and gibberellic acid (GA3), and the counteractive effect of these two compounds on growth and tuber yield of greenhouse-grown Norland and Russet Burbank
potatoes were investigated. Plants were grown either in 1.5-liter pots (15 cm deep) or 3.0-liter pots (18 cm deep) and received
a foliar application of either 1.5 mm PTZ or 9 × 10−3 mm GA3 at early or late stolon initiation. Some plants that had been foliar treated with 1.5 mm PTZ at early stolon initiation were foliar treated with 9 × 10−3 mm GA3 at late stolon initiation. PTZ reduced haulm length in both cultivars significantly, particularly when the treatment was
applied at early stolon initiation, but the late treatment reduced haulm length only when growing in 3.0-liter pots. Irrespective
of the timing of treatment, GA3 increased haulm length in Norland growing in both pot sizes, but the treatment increased haulm length in Russet Burbank only
when applied at late stolon initiation. GA3 applied after PTZ did not overcome the growth-inhibiting effect of the PTZ treatment. The PTZ treatment effectively increased
usable tuber number/plant (UTN) in Norland, but PTZ had no effect on UTN in Russet Burbank. PTZ reduced usable tuber weight/plant
(UTW) only in Norland growing in 1.5-liter pots. By contrast, GA3 increased UTN only when treated at late stolon initiation of 1.5-liter pot-grown Norland, whereas the same treatment was
effective when applied only at early stolon initiation for Russet Burbank. For Norland, the increase in UTN by early applied
PTZ was reduced by the subsequent application of GA3. The use of 3.0-liter pots for minituber production in both Norland and Russet Burbank appears to have no advantage over
growing in 1.5-liter pots, particularly when PTZ or GA3 is used to enhance tuberization.
Received May 30, 1997; accepted February 3, 1998 相似文献
16.
Controlled environmental experiments were carried out to determine the phytotoxicity of several graminicides on wild oat
(Avena futua L.) as influenced by combination of drought and temperature stress or drought and low relative humidity. Compared with unstressed
conditions (20/15°C plus adequate soil moisture), imazamethabenz phytotoxicity to wild oat was reduced significantly when
plants were exposed to a combination of drought and high temperature (30/20°C) stress. Imazamethabenz phytotoxicity was reduced
almost as much by high temperature stress alone as by a combined temperature and drought stress. When herbicides were applied
to wild oat plants subjected to drought alone or to drought plus high temperature, the observed reduction in phytotoxicity
from greatest to least was: fenoxaprop = diclofop > flamprop > imazamethabenz. Fenoxaprop performance was most inhibited by
the combination of drought plus high temperature, although drought alone and to a lesser degree, high temperature alone, inhibited
fenoxaprop action. High temperature had an adverse effect on the efficacy of fenoxaprop at lower application rates. Raising
fenoxaprop application rates to 400 g ha−1 overcame the inhibition caused by high temperature alone but only partially alleviated the effect of drought combined with
high temperature. When plants were grown under a low temperature regimen the imposition of drought stress had little effect
on imazamethabenz phytotoxicity but did reduce fenoxaprop phytotoxicity. At 25/15°C drought reduced the phytotoxicity of fenoxaprop
and diclofop greatly but had no significant impact on the performance of any of the herbicides examined, regardless of soil
moisture regimen.
Received April 14, 1997; accepted September 22, 1997 相似文献
17.
Z. Guoping 《Journal of Plant Growth Regulation》1997,16(1):21-25
Gibberellic acid3 (GA3) modification of some growth and physiologic effects of paclobutrazol (PP333) was studied by applying PP333 alone and in combination with GA3 at the tillering stage of wheat. Results showed that GA3 weakened the effect of PP333 on tillering and shortening the plant, increased the dry matter accumulation of different tillers, improved plant nitrogen
metabolism by favoring nitrogen translocation into tillers at late growth stage, and stimulated tiller development. All of
these reduced the difference in spike weight among tillers and the main stem. Compared with control, there were more spikes
per plant and fewer grain per spike in the PP333 treatment, but all yield components developed positively in the treatment consisting of the mixture of GA3 and PP333.
Received May 22, 1996; accepted November 14, 1996 相似文献
18.
The effect of N-2-(6-methyl-pyridyl)-aminomethylene bisphosphonic acid (M-pyr-AMBPA), a compound previously shown to exhibit herbicidal properties
on whole plants and to inhibit in vitro activity of the first enzyme in the shikimate pathway, 3-deoxy-d-arabino-heptulosonate-7-phosphate (DAHP) synthase, was investigated on Nicotiana plumbaginifolia suspension cultured cells and compared to that of the herbicide glyphosate. The addition of M-pyr-AMBPA from 10−4 to 10−3 M was found to cause a severe cell growth reduction. Kinetic analysis of partially purified DAHP synthase accounted for non-competitive
inhibition type with respect to both phospho-enol-pyruvate and erythrose-4-phosphate, with KI values of 0.43 and 0.62 mM, respectively. Amino acid pool measurements of cells grown in the presence of sublethal doses
of M-pyr-AMBPA pointed to an actual reduction of free aromatic amino acids, showing that DAHP synthase inhibition takes place
in vivo, and suggesting that the interference of this aminophosphonate with plant aromatic biosynthesis may account for a large part
of its phytotoxicity. However, exogenous supply of a mixture of phenylalanine, tyrosine and tryptophan failed to achieve full
reversal of cell growth inhibition, yet the occurrence of other target(s) cannot be ruled out.
Received November 24, 1998; accepted June 3, 1999 相似文献
19.
2-Aminoindan-2-phosphonic acid (AIP) retarded the growth of duckweed, Spirodela punctata, and increased its dry mass. The accumulation of starch was observed at all concentrations of AIP at 8 days after treatment.
The increase in starch was inversely proportional to the growth. The retarded growth of Spirodela by AIP was not limited only by excessive starch accumulation.
Received December 8, 1997; accepted June 2, 1998 相似文献
20.
Effect of Wild-Type and Mutant Plant Growth-Promoting Rhizobacteria on the Rooting of Mung Bean Cuttings 总被引:1,自引:0,他引:1
Mung bean cuttings were dipped in solutions of wild type and mutant forms of the plant growth-promoting rhizobacterium Pseudomonas putida GR12-2 and then incubated for several days until roots formed. The bacteria P. putida GR12-2 and P. putida GR12-2/aux1 mutant do not produce detectable levels of the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase, whereas P. putida GR12-2/acd36 is an ACC deaminase minus mutant. All bacteria produce the phytohormone indole-3-acetic acid (IAA), and P. putida GR12-2/aux1 overproduces it. Treatment of cuttings with the above-mentioned bacteria affected the rates of ethylene production in the
cuttings in a way that can be explained by the combined effects of the activity of ACC deaminase localized in the bacteria
and bacterial produced IAA. P. putida GR12-2 and P. putida GR12-2/acd36-treated cuttings had a significantly higher number of roots compared with cuttings rooted in water. In addition, the wild
type influenced the development of longer roots. P. putida GR12-2/aux1 stimulated the highest rates of ethylene production but did not influence the number of roots. These results are consistent
with the notion that ethylene is involved in the initiation and elongation of adventitious roots in mung bean cuttings.
Received October 21, 1998; accepted January 3, 1999 相似文献