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1.
Thirty-day-old plants of mustard (Brassica juncea L.) were sprayed with 10−10, 10−8, or 10−6 M aqueous solution of 28-homobrassinolide (HBR). The HBR-treated plants were healthier than those treated with water and
yielded more. Maximum increase over control was found in 60-d-old, 10−8 M-HBR-treated plants in fresh and dry mass per plant, carbonic anhydrase (CA, E.C. 4.2.1.1) activity, and net photosynthetic
rate (P
N), at harvest in number of pods per plant and seed yield per plant (the respective values were 25, 30, 34, 69, 24, and 29
%). A further increase in the concentration of HBR (10−6 M) did not make any additional impact on the growth and yield. Increased CA activity and P
N were correlated with growth and seed yield.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
2.
Soaking seeds of Lens culinaris with 28-homobrassinolide increased nitrate reductase activity and grain yield in the field in India 总被引:1,自引:0,他引:1
Surface‐sterilised seeds of Lens culinaris cv. Pusa‐6 were soaked in 0 M, 10?6 M, 10?8 M or 10?10 M aqueous solutions of 28‐homobrassinolide (HBR) for 4 h, 8 h or 12 h and planted in the field in a sandy loam soil. Plants were sampled 60, 90 and 120 days after sowing (DAS). Soaking with HBR decreased root length and nodule number per plant but increased nitrate reductase activity (E.C.1.6.6.1). Soaking with HBR also increased grain yield at the final harvest 140 DAS. The greatest increase was obtained with an HBR concentration of 10?8 M. 相似文献
3.
The plants of mung bean (Vigna radiata L. Wilczek) were raised from the seeds soaked in water (control), IAA or 4-C-IAA (10−6, 10−8 or 10−10 M) for 8 or 12 h. The plants were allowed to grow in a net house and were sampled at 30 and 45 days after sowing (DAS). Both
IAA and 4-Cl-IAA significantly affected the growth (length, fresh and dry mass of roots and shoots), the number of nodules,
their fresh and dry mass and the activity of nitrogenase. However, the contents of nitrogen and carbohydrate exhibited a decrease
in response to both the auxins. 4-Cl-IAA, at a concentration of 10−8 M, generated the best response. Moreover, 4-Cl-IAA at other two concentrations (10−6 and 10−10 M) was much more active than any of the IAA concentration used. 相似文献
4.
《Environmental and Experimental Botany》2007,59(2):217-223
The response of chickpea (Cicer arietinum L.) cv. KPG-59 to pre-sowing seed treatment with 28-homobrassinolide (HBR) and/or sodium chloride (NaCl) was investigated. The seeds imbibed in aqueous solution of 10−10 or 10−8 M of HBR for 8 h, resulted in an increase in the values for most of the characteristics of shoot and root at 90-day stage and seed yield, at harvest. The plants resulting from the seeds soaked in HBR (10−8 M) possessed 23% and 31% higher leaf nitrate reductase (E.C. 1.6.6.1) and carbonic anhydrase (E.C. 4.2.2.1) activities, 34% more dry mass, 30% higher nodule number, 31% and 18% more nodule fresh and dry mass, compared with water soaked, control. Leghaemoglobin content and nitrogenase activity (E.C. 1.7.99.2) were 28% and 30% higher while nodule nitrogen and carbohydrate contents decreased by 5% and 6%, compared with the control. Moreover, seed yield increased by 26% over the control, at harvest. The values for all the above characteristics declined significantly, in the plants raised from the seeds soaked in NaCl. However, this ill effect was overcome, if NaCl treatment was given before or after HBR treatment. 相似文献
5.
H. Zhang M. J. Wang L. Y. Hu S. H. Wang K. D. Hu L. J. Bao J. P. Luo 《Russian Journal of Plant Physiology》2010,57(4):532-539
Effects of NaHS, H2S donor, on germination and antioxidant metabolism in wheat (Triticum aestivum L.) seeds under osmotic stress were investigated. With the enhancement of osmotic stress, which was mimicked by PEG-6000,
the seed germination dropped gradually. NaHS treatment could promote wheat seed germination against osmotic stress in a dose-dependent
manner; while Na+ and other sulfur-containing components, such as S2−, SO42−, SO32−, HSO4− and HSO3−, were not able to improve seed germination as NaHS did, confirming H2S or HS− derived from NaHS contribute to the protective roles. Further experiments showed that NaHS treatment combined with PEG enhanced
the activities of amylase and esterase in comparison to PEG treatment alone. Alternatively, NaHS treatment significantly reduced
malondialdehyde and hydrogen peroxide accumulation in seeds. Significant enhancement of catalase and ascorbate peroxidase
activities and decrease in lipoxygenase activity were observed in NaHS treated seeds, while peroxidase and superoxide dismutase
activities were not affected as compared with the control. Furthermore, the H2S donor treatment could retain higher levels of endogenous H2S in wheat seeds under osmotic stress. These data indicated that H2S played a protective role in wheat seed against osmotic stress. 相似文献
6.
Filtrates from crushed Moringa oleifera seeds were tested for their effects on growth and Photosystem II efficiency of the common bloom-forming cyanobacterium Microcystis aeruginosa. M. aeruginosa populations exhibited good growth in controls and treatments with 4- and 8-mg crushed Moringa seeds per liter, having similar growth rates of 0.50 (±0.01) per day. In exposures of 20- to 160-mg crushed Moringa seeds L−1, growth rates were negative and on average −0.23 (±0.05) .day−1. Presumably, in the higher doses of 20- to 160-mg crushed seeds per liter, the cyanobacteria died, which was supported by
a rapid drop in the Photosystem II efficiency (ΦPSII), while the ΦPSII was high and unaffected in 0, 4, and 8 mg L−1. High-density populations of M. aeruginosa (chlorophyll-a concentrations of ∼270 μg L−1) were reduced to very low levels within 2 weeks of exposure to ≥80-mg crushed seeds per liter. At the highest dosage of 160 mg L−1, the ΦPSII dropped to zero rapidly and remained nil during the course of the experiment (14 days). Hence, under laboratory conditions,
a complete wipeout of the bloom could be achieved. This is the first study that yielded evidence for cyanobactericidal activity
of filtrate from crushed Moringa seeds, suggesting that Moringa seed extracts might have a potential as an effect-oriented measure lessening cyanobacterial nuisance. 相似文献
7.
Unimbibed Amaranthus caudatus seeds were found to contain stachyose, raffinose, verbascose, sucrose, galactinol, myo-inositol, glucose and fructose, while no galactose, maltose and maltotriose was detected. During imbibition, seed concentrations
of verbascose, stachyose, raffinose, galactinol, myo-inositol (temporary) and fructose (transient) were observed to decrease; concentrations of galactose and maltose remained
fairly constant, while those of sucrose, glucose and maltotriose increased, the increase in sucrose concentration was only
temporary. Effects of gibberellin A3 (GA3) at 3 × 10−4 M and ethephon at 3 × 10−4 M alone or in the presence of methyl jasmonate (Me-JA) at 10−3 M on concentrations of soluble sugars during germination of A. caudatus seeds were examined. Me-JA was found to inhibit seed germination and fresh weight of the seeds, but did not affect sucrose,
myo-inositol, galactose and maltose concentrations during imbibition for up to 20 h. The exogenously applied GA3 was observed to enhance germination, stachyose breakdown and glucose concentration after 20 h of incubation. Ethephon stimulated
seed germination as well as utilisation of stachyose, galactinol (both after 14 and 20 h) and raffinose (after 14 h of incubation).
Although the stimulatory effect of either GA3 or ethephon on seed germination was blocked by Me-JA; these stimulators increased mobilisation of raffinose and stachyose,
but only ethephon enhanced both glucose and fructose after 14 and/or 20 h of incubation in the presence of Me-JA. The maltose
concentration was increased by both GA3 and ethephon alone and in the presence of Me-JA. Of the growth regulators studied, ethephon alone and/or in combination with
Me-JA significantly increased the concentrations of glucose, fructose, galactose, maltose and maltotriose. The differences
in sugar metabolism appear to be linked to ethylene or GA3 applied simultaneously with Me-JA. 相似文献
8.
Mónica M. Storni María Cristina Zaccaro Ana Capano Ana María Stella Gloria Zulpa 《World journal of microbiology & biotechnology》2007,23(6):833-836
Summary Metal ions are both essential and potentially toxic. The aim of this work was to demonstrate that diazotrophic cyanobacterium
Tolypothrix tenuis N° 54 can tolerate toxic concentrations of Ni2+ in order to use the biomass in biofilters or as biofertilizer. For this purpose, growth, pigment and protein contents and
catalase activity of T. tenuis growing in increasing concentrations of Ni2+ ranging from 10−10 to 10−4 M were assesed. The strain did not grow at Ni2+ concentration of 10−4 M, but at lower concentrations there were no significant differences with the control; it was tolerant at 10−10 and 10−8 M. Nickel concentration of 10−6 M is toxic for this cyanobacterial strain, because dry weight decreased by 30%; allophycocyanin and phycoerythrin decreased
by 92% and 98%, respectively and protein content increased by 42%. Chlorophyll a concentration was more than double the control value in 10−10 and 10−8 M, but in 10−6 M it decreased by 19%. Catalase (E.C. 1.11.1.6) activity doubled the control value in the lowest nickel concentration whereas
in 10−8 M there was no significant difference with the control and in 10−6, it decreased by 78%. The living biomass of this strain could be used as a step in the bioremediation process in waters contaminated
with concentrations of nickel lower than 10−6 M and eventually as a biofertilizer. 相似文献
9.
Nobuhiko Ohga 《Ecological Research》1992,7(3):341-353
Herbaceous lomas in the Peruvian coastal desert, of South America establish in spring, and its habitat is limited to the southern
or southwestern slopes along the coast that are affected by thick fog. The time of appearance, the duration and the thickness
of the fog vary greatly from year to year, so the lomas can grow only in habitats with enough water to, sustain seed germination
and plant growth. This paper studies the species composition and density of the buried seed population, of the herbaceous
lomas of Loma Ancon in order to clarify the mechanisms of the lomas' establishment. The mean number of species with viable
seeds was about, 12 spp. m−2 and that of dead seeds was about 22 spp. m−2. The dominant species wereSolanum tuberiferum, S. pinnatifidum andNolana humifusa, both in viable and dead seeds. Viable seed density was about 5000–8000 seeds m−2, which is comparable with the seed densities of other herbaceous communities. Dead seed density was about 15000–27000 seeds
m−2, or nearly three times the viable seed density, because the rate of decomposition was slow in the extremely dry conditions.
The net increase of viable seeds by seed production was estimated at about 5000 seeds m−2 in 1980, and the increase in the number of dead seeds was 2200 seeds m−2. 相似文献
10.
Soetikno S. Sastroutomo 《Journal of plant research》1980,93(4):265-273
Effects of environmental conditions and growth regulators on release from dormoncy of axillary turions inHydrilla verticillata were investigated.
Coll treatment at 2 C for 33 days produced the most complete release from dormancy. One week of 2 C treatment was sufficient
for the germination; however, longer cold periods produced more rapid growth in shoot or root lengths as well as a shorter
lag time for germination.
Dormancy in turions could be broken by a photoperiod of 16 hr but not by on of 8 or 12 hr, nor by continuous lighting. When
a cold treatment was applied turions grew out in response to all of the photoperiodic conditions.
Red and far-red irradiation during the incubation after a cold treatment promoted gremination; blue and green light markedly
inhibited the germination.
At 10−4 and 10−5 M, gibberellic acid broke dormancy of non-cold treated turions, but was toxic at 10−4 M to the development after germination. Gibberellic acid promoted growth of cold treated turions even at 10−6 M. Indoleacetic acid at 10−4, 10−5 and 10−6 M induced outgrowth of both non-cold treated and cold treated turions. Apparently normal growth and development was observed
in a high concentration of indoleacetic acid. 相似文献
11.
Julio C. Davila Chandrasekara G. Reddy Patrick J. Davis Daniel Acosta 《In vitro cellular & developmental biology. Plant》1990,26(5):515-524
Summary The present study was undertaken to assess and compare the toxic effects of papaverine hydrochloride and its metabolites.
Primary cell cultures of rat hepatocytes were treated with papavarine (papaver), 3′-O-desmethyl (3′-OH), 4′-O-desmethyl (4′-OH),
and 6-O-desmethyl (6-OH) papaverine at 1×10−5, 1×10−4, and 1×10−3
M for 4,8, 12, and 24-h periods. Cell injury was determined by: a) cell viability using the trypan blue exclusion test; b)
cytosolic enzyme leakage of lactate dehydrogenase and aspartate aminotransferase; c) morphologic alterations; and d) lactate:
pyruvate (L:P) ratios. Cell cultures showed concentration-and time-dependent responses. For example, a decrease in cell viability
and an increase in enzyme leakage were observed after cell treatment with 1×10−4 and 1×10−3
M papaver for 8 h; 1×10−3
M 6-OH papaverine for 8 h and 1×10−4
M for 24 h; and 1×10−3
M 4′-OH papaverine for 24 h (P<0.05). Furthermore, changes in morphology correlated to cell viability and enzyme release in those cultures treated with
papaver, 4′-OH and 6-OH papaverine. Some of these changes included size deformation, cell detachment from the dishes, and
cell necrosis. On the other hand, an increase in L:P ratios (P<0.05) was detected with papaver as early as 8 h with 1×10−4 and 1×10−3
M and 12 h with 1×10−5
M; 6-OH showed an increase, in L:P ratios at 8 h with 1×10−3
M and 12 h with 1×10−4
M; these changes were evident with 4′-OH at 12 h with 1×10−3
M. In contrast, cells treated with 3′-OH papaverine did not show significant damage with any time period and concentration
used in this study. The results of this study indicate that papaverine-derived metabolites are less cytotoxic than its parent
compound, papaver. The toxicity was ranked as follows: papaver>6-OH>4′-OH>−3′-OH.
This work was supported in part by grant ES04200-02 from the National Institute of Environmental Health Sciences, Bethesda,
MD.
Presented in part at the fall ASPET meeting in Salt Lake City, August, 1989. Daniel Acosta is a Burroughs Wellcome Scholar
in Toxicology. 相似文献
12.
Dumlupinar R Genisel M Erdal S Korkut T Taspinar MS Taskin M 《Biological trace element research》2011,143(3):1740-1745
The present study was performed to determine the changes in inorganic element content in barley leaves of mammalian sex hormones
(MSH). Barley leaves were sprayed with 10−4, 10−6, 10−9, 10−12, 10−15 M concentrations of progesterone, β-estradiol, and androsterone at 7th day after sowing. The plants were harvested at the
end of 18 days after treatment with MSH solutions. The inorganic element concentrations were determined using wavelength dispersive
X-ray fluorescence spectroscopy technique. Although the all MSH concentrations significantly (p < 0.05) increased the concentrations of calcium, magnesium, phosphorus, sulfur, copper, manganese, aluminum, zinc, iron,
potassium, and chlorine, it decreased those of sodium concentration in barley leaves. The maximum changes in the element concentrations
were obtained at 10−9 M for plant leaves treated with progesterone, 10−6 M for plant leaves treated with β-estradiol and androsterone. The present study elucidated that MSH significantly (p < 0.05) affected the inorganic element concentrations in barley leaves. 相似文献
13.
The thickening that appeared on maize roots under the influence of 6-benzylaminopurine and α-naphthylacetic acid (concentration
10−5, 10−6, 10−7 and 10−8 M) were analysed. The changes in length and width of maize roots at the edge of elongation zone after 24,48 and 72 h of treatment
were studied. The growth in length of cells at the edge of elongation zone stopped abruptly but the growth in width slowly
continued. So, the growth of cells in length and width under the influence of growth regulators was not simultaneous. They
had distinct time limits. 相似文献
14.
Jana Honnerová Olga Rothová Dana Holá Marie Kočová Ladislav Kohout Miroslav Kvasnica 《Journal of Plant Growth Regulation》2010,29(4):500-505
The effect of various concentrations of exogenously applied 24-epibrassinolide (E) and 2α,3α,17β-trihydroxy-5α-androstan-6-one
(A) on the activities of Photosystem 1 and the Hill reaction, the contents of photosynthetic pigments, and the growth of plants
was examined in young maize (Zea mays L.) plants subjected to long-term chilling stress or grown in normal-temperature conditions. Neither the activity of Photosystem
1 nor the Hill reaction activity of plants was in any way affected by the treatment with brassinosteroids (BRs), which suggests
that the photosynthetic complexes of thylakoid membranes are not the primary site of the influence of BRs on photosynthesis.
An extremely low (10−14 M) concentration of A applied to the nonstressed plants significantly increased the length of their 4th to the 7th leaves
and their height, as well as the contents of chlorophylls a and b and total carotenoids. However, under chilling conditions, this positive effect was significant for the chlorophyll content
only and higher concentrations of BRs (10−12, 10−10, 10−8 M) usually had no effect at all. 相似文献
15.
The critically endangered and perennial alpine endemic angiosperms, namely, Aquilegia nivalis, Lagotis cashmeriana and Meconopsis latifolia inhabit such habitats in the Kashmir Himalaya that are characterised by short growing season and heavy snow cover for about
3–4 months during winter season. The seeds of these species under natural conditions experience a long period of pre-chilling
during winter prior to their germination in following spring season. Taking cue from such a requirement, present study investigated
the effect of chilling and exogenous application of growth hormones, NO3
− and NH4
+ on total percent germination of otherwise deep-dormant seeds of these species, under alternate light/dark and continuous
dark light regimes. Prolonged pre-chilling followed by treatment of seeds with different doses of GA3 had a pronounced stimulatory effect on the total germination percentage in all the three species. In fact, highest germination
percentage in A. nivalis was recorded only when pre-chilled seeds were treated with 1.5 mM GA3 under alternate light/dark conditions. Likewise, germination of pre-chilled seeds of L. cashmeriana with ruptured seed coats was improved when treated with various concentrations of GA3. Seed germination in M. latifolia was also favourably influenced by treatment of pre-chilled seeds with GA3 or nitrogen applied either as NO3
− or as NH4
+ under alternate light/dark conditions. Treatment of seeds with kinetin (6-furfuryl-aminopurine) had no significant influence
on germination percentage in any of the three species. Thus, prolonged chilling of seeds followed by their treatment with
GA3 under alternate light/dark conditions are the requirements necessary for seed germination in these species. 相似文献
16.
Buckwheat (Fagopyrum esculentum Moench. cv Jianxi) is highly resistant to Al stress and is known to be an Al-accumulator. Pot experiments were carried out
in a greenhouse to investigate the accumulation of Al in leaves and seeds of buckwheat. Plants were grown for 12 weeks in
a strong acid soil amended with or without CaCO3 at a rate of 1 g kg−1 soil. Old leaves accumulated as much as 10 g kg−1 Al of dry weight when the plants were grown in the acid soil, while the Al concentrations in leaves immediately adjacent
to seeds, seed coats, and embryos were, on average, 4516, 41.2 and 7.7 mg kg−1, respectively. The Al concentration significantly decreased in leaves when the plants were grown in the limed soil, and the
Al concentrations in leaves immediately adjacent to seeds, seed coats, and embryos were, on average, 1586, 21.3 and 3.1 mg kg−1, respectively. These results show that seeds accumulate much less Al than buckwheat leaves. The underlying mechanisms are
discussed.
Section Editor: H. Lambers 相似文献
17.
The present piece of work highlights the comparative effects of two active forms of brassinosteroids (BRs), 28-homobrassinolide
(HBL) and 24-epibrassinolide (EBL), on growth parameters, carbonic anhydrase activity and photosynthetic parameters in Lycopersicon esculentum (cv. K-21) sampled at 45 (24 h after spray) and 60 days after sowing, under natural conditions. Out of the two active forms
of BR, EBL proved better than HBL in improving the above parameters, when applied as foliar spray. Of the three concentrations
(10−6 M, 10−8 M or 10−10 M) of HBL and EBL, 10−8M proved best in both cases. 相似文献
18.
Tomoki Kai Kazumi Nimura Hajime Yasui Hiroyuki Mizuta 《Journal of applied phycology》2006,18(1):95-101
Young sporophytes of Laminaria japonica Areshoug were cultured in six indole-acetic acid (IAA) concentrations (0, 10−8, 10−7, 10−6, 10−5, 10−4 M) to examine the effect of auxin on growth. The effects of auxin on sorus formation were also examined by using discs taken from the adult sporophyte. The auxin contents and IAA oxidase activities in the thallus and sorus parts of the sporophyte were determined with the blade and sporophyll of other Laminariales plants, Undaria pinnatifida (Harvey) Suringar and Alaria crassifolia Kjellman. The young sporophytes of L. japonica showed highest elongation rate in 10−5 M IAA. In contrast, the sorus formation on the discs cultured in 10−5 M IAA was markedly delayed in comparison with other concentrations, indicating that sorus formation was suppressed by IAA. Free and conjugated auxin contents were lower in the reproductive parts than in the vegetative parts. In three Laminariales sporophytes, IAA oxidase activity was about 3–9 times higher in the reproductive parts than in the vegetative parts. Taken together these results suggest that the growth and reproduction of Laminariales sporophytes are regulated by internal auxin levels. Elucidating the regulation mechanism is likely to provide information that is important for the management of plant production and the assessment of the physiological status of plants in the field. 相似文献
19.
Mi-Young Oh Sang Beum Lee Deuk-Hee Jin Yong-Ki Hong Hyung-Joo Jin 《Journal of applied phycology》2010,22(4):453-458
We determined the structure of two compounds, namely, 5,8,11,14,17-eicosapentaenoic acid (EPA) and di-n-octylphthalate (DnOP), which have algicidal activity against the toxic dinoflagellate, Cochlodinium polykrikoides. The polyunsaturated fatty acid EPA and the anthropogenic DnOP were isolated from the MeOH extract of the red alga Corallina pilulifera. We also found that a commercial EPA has algicidal activity identical to that of the EPA purified from C. pilulifera. At low inoculum (5.0 × 102 cells mL−1), the highest algicidal activity of a commercial EPA exhibited approximately 92.6% algicidal activity after 1 h and 96.8%
after 6 h treatment at 6 μg mL−1, respectively. At high inoculum (1.0 × 104 cells mL−1), the strongest algicidal activity of EPA showed 69.5% after 1 h and 75.5% algicidal activity after 6 h treatment at 6 μg
mL−1, respectively. However, EPA did not show algicidal activity against several microalgae used in aquaculture such as Pavlova lutheri, Tetraselmis suecica, Isochrysis galbana, and Nannochloris oculata for 6 h treatment at 6 μg mL−1. The algicidal activity of the five red tide strains to EPA (3 μg mL−1) showed about 86.6%, 86.6%, and 67.3% algicidal activity against Skeletonema costatum, Chaetoceros curvisetus, and C. polykrikoides after 1 h treatment at low inoculum (5.0 × 102 cells mL−1), respectively, but not against Prorocentrum minimum and Scrippsiella trochoidea. We concluded that EPA might be useful as a controlling agent of harmful algal blooms. 相似文献
20.
An experiment was conducted under controlled conditions, in which grains of wheat (Triticum aestivum L. cv. Raj-3077) were soaked in 0, 1, 3 and 5 μM aqueous solutions of 28-homobrassinolide (HBR) for 4, 8 and 12 hours. The
seedlings raised from the grains pre-treated with HBR possessed significantly higher leaf number, fresh and dry weight·plant−1, nitrate reductase (NR,E.C. 1.6.6.1) and carbonic anhydrase (CA, E.C. 4.2.1.1) activities on 25 and 35 days, after sowing.
The soaking of the grains in 3 μM concentration for 8 or 12 hours produced the most vigorous seedlings. 相似文献