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1.
Mónica Calvo-Polanco Melanie D. Jones Janusz J. Zwiazek 《Acta Physiologiae Plantarum》2009,31(3):515-522
In the present study, we investigated the effects of pH treatments on NaCl tolerance in mycorrhizal and non-mycorrhizal American
elm. American elm (Ulmus americana) seedlings were inoculated with Hebeloma crustuliniforme, Laccaria bicolor or with both mycorrhizal fungi and subsequently subjected to different pH solutions (pH 3, 6 and 9) containing 0 mM (control)
and 60 mM NaCl for 4 weeks. Inoculation with the mycorrhizal fungi did not have a large effect on seedling dry weights when
the pH and NaCl treatments were considered independently. However, when the inoculated seedlings were treated with 60 mM NaCl
at pH 3 or 6, shoot to root ratios and root hydraulic conductivity were higher compared with non-inoculated plants, likely
reflecting changes in seedling water flow properties. At pH 6, transpiration rates were about twofold lower in non-inoculated
plants treated with NaCl compared with non-treated controls. For NaCl-treated H. crustuliniforme- and L. bicolor-inoculated plants, the greatest reduction of transpiration rates was at pH 9. Treatment with 60 mM NaCl reduced leaf chlorophyll
concentrations more in non-inoculated compared with inoculated plants, with the greatest, twofold, decrease occurring at pH
6. At pH 3, root Na concentrations were higher in inoculated than non-inoculated seedlings; however, there was no effect of
inoculation on root Na concentrations at pH 6 and 9. Contrary to the roots, the leaves of inoculated plants had lower Na concentrations
at pH 6 and 9, but not at pH 3. The results point to an interaction between ECM fungi and root zone pH for salt tolerance
of American elm. 相似文献
2.
Zuzana Vatehová Karin Kollárová Ivan Zelko Danica Richterová-Kučerová Marek Bujdoš Desana Lišková 《Biologia》2012,67(3):498-504
The objective of this study was to determine the effect of silicon (Si) and cadmium (Cd) on root and shoot growth and Cd uptake
in two hydroponically cultivated Brassica species (B. juncea (L.) Czern. cv. Vitasso and B. napus L. cv. Atlantic). Both species are potentially usable for phytoextraction. Inhibitory effects of Cd on root elongation were
diminished by the impact of Si. Primary roots elongation in the presence of Cd + Si compared with Cd was stronger and the
number of lateral roots was lower in B. juncea than in B. napus. Cd content per plant was higher in B. napus roots and shoots compared with B. juncea. Suberin lamellae were formed closer to the root apex in Cd + Si than in Cd treated plants and this effect was stronger in
B. napus than in B. juncea. Accelerated maturation of endodermis was associated with reduced Cd uptake. Cd decreased the content of chlorophylls and
carotenoids in both species, but Si addition positively influenced the content of photosynthetic pigments which was higher
in B. napus than in B. juncea. Si enhanced more substantially translocation of Cd into the shoot of B. napus than of B. juncea. Based on our results B. napus seems to be more suitable for Cd phytoextraction than B. juncea because these plants produce more biomass and accumulate
higher amount of Cd. The protective effect of Si on Cd treated Brassica plants could be attributed to more extensive development of suberin lamellae in endodermis. 相似文献
3.
Salinity adversely affects plant growth and development. Halotolerant plant-growth-promoting rhizobacteria (PGPR) alleviate
salt stress and help plants to maintain better growth. In the present study, six PGPR strains were analyzed for their involvement
in salt-stress tolerance in Arachis hypogaea. Different growth parameters, electrolyte leakage, water content, biochemical properties, and ion content were analyzed in
the PGPR-inoculated plants under 100 mM NaCl. Three bacterial strains, namely, Brachybacterium
saurashtrense (JG-06), Brevibacterium
casei (JG-08), and Haererohalobacter (JG-11), showed the best growth of A. hypogaea seedlings under salt stress. Plant length, shoot length, root length, shoot dry weight, root dry weight, and total biomass
were significantly higher in inoculated plants compared to uninoculated plants. The PGPR-inoculated plants were quite healthy
and hydrated, whereas the uninoculated plant leaves were desiccated in the presence of 100 mM NaCl. The percentage water content
(PWC) in the shoots and roots was also significantly higher in inoculated plants compared to uninoculated plants. Proline
content and soluble sugars were significantly low, whereas amino acids were higher than in uninoculated plants. The MDA content
was higher in uninoculated plants than in inoculated plants at 100 mM NaCl. The inoculated plants also had a higher K+/Na+ ratio and higher Ca2+, phosphorus, and nitrogen content. The auxin concentration was higher in both shoot and root explants in the inoculated plants.
Therefore, it could be predicted that all these parameters cumulatively improve plant growth under saline conditions in the
presence of PGPR. This study shows that PGPR play an important role in inducing salinity tolerance in plants and can be used
to grow salt-sensitive crops in saline areas. 相似文献
4.
The effects of NaCl stress on growth, water status, contents of protein, proline, malondialdehyde (MDA), various sugars and
photosynthetic pigments were investigated in seedlings of Salicornia persica and S. europaea grown in vitro. Seeds were germinated under NaCl (0, 100, 200, 300, 400, 500 and 600 mM) on Murashige and Skoog medium for 45 d. The shoot
growth of both species increased under low NaCl concentration (100 mM) and then decreased with increasing NaCl concentrations.
In contrast to S. persica, root length in S. europaea reduced steadily with an increase in salinity. Proline content in S. persica was higher than in S. europaea at most NaCl concentrations. Proline, reducing saccharide, oligosaccharide and soluble saccharide contents increased under
salinity in both species. In contrast, contents of proteins and polysaccharides reduced in both species under salt stress.
MDA content remained close to control at moderate NaCl concentrations (100 and 200 mM) and increased at higher salinities.
MDA content in S. europaea was significantly higher than S. persica at higher salinities. Salt treatments decreased K+ and P contents in seedlings of both species. Significant reduction in contents of chlorophylls and carotenoids due to NaCl
stress was also observed in seedlings of both species. Some differences appeared between S. persica and S. europaea concerning proteins profile. On the basis of the data obtained, S. persica is more salt-tolerant than S. europaea. 相似文献
5.
The study aimed to investigate the effects of an AM fungus (Glomus intraradices Schenck and Smith) on mineral acquisition in fenugreek (Trigonella foenum-graecum) plants under different levels of salinity. Mycorrhizal (M) and non-mycorrhizal (NM) fenugreek plants were subjected to four
levels of NaCl salinity (0, 50, 100, and 200 mM NaCl). Plant tissues were analyzed for different mineral nutrients. Leaf senescence
(chlorophyll concentration and membrane permeability) and lipid peroxidation were also assessed. Under salt stress, M plants
showed better growth, lower leaf senescence, and decreased lipid peroxidation as compared to NM plants. Salt stress adversely
affected root nodulation and uptake of NPK. This effect was attenuated in mycorrhizal plants. Presence of the AM fungus prevented
excess uptake of Na+ with increase in NaCl in the soil. It also imparted a regulatory effect on the translocation of Na+ ions to shoots thereby maintaining lower Na+ shoot:root ratios as compared to NM plants. Mycorrhizal colonization helped the host plant to overcome Na+-induced Ca2+ and K+ deficiencies. M plants maintained favorable K+:Na+, Ca2+:Na+, and Ca2+:Mg2+ ratios in their tissues. Concentrations of Cu, Fe, and Zn2+ decreased with increase in intensity of salinity stress. However, at each NaCl level, M plants had higher concentration of
Cu, Fe, Mn2+, and Zn2+ as compared to NM plants. M plants showed reduced electrolyte leakage in leaves as compared to NM plants. The study suggests
that AM fungi contribute to alleviation of salt stress by mitigation of NaCl-induced ionic imbalance thus maintaining a favorable
nutrient profile and integrity of the plasma membrane. 相似文献
6.
In vitro culture is an important aid for ex situ conservation of rare, endemic or threatened plants. In this work, we establish an efficient method for the seed germination,
seedling development, and axillary shoot propagation of Centaurea zeybekii Wagenitz. The seeds, collected from a wild population, were surface sterilised and cultured on various in vitro germination media. The effects of photoperiod and temperature on seed germination were also investigated. Germinations were
obtained after 6 weeks in culture and the radicle emergence was evaluated as a main indicator. A high frequency of germination
was obtained on distilled water supplemented with vitamines and 1 mg/L GA3. Although the seed germination frequencies were not affected by photoperiod, the highest germination frequency was obtained
at 24 ± 2°C. A high frequency of axillary shoot proliferation was produced on MS medium supplemented with 1 mg/L BA. Then,
the axillary shoots were separated and transferred to MS medium with or without plant growth regulators for rooting. Rhizogenezis
was promoted after 6 weeks only in MS and 1/2 MS media containing 0.5 mg/L IBA. The rooting process was very slow and the
percentage of shoot rooting was also very low (15%).
The present study not only enables reinforcement of wild plant populations using ex situ growth of individuals, but it also helps to large number of aseptic seedling to use it in clonaly micropropagation studies. 相似文献
7.
The effect of excessive Cd on the growth and metal uptake by leafy vegetables Brassica chinensis L. (cv. Wuyueman) and Brassica pekinensis (Lour.) Rupr. (cv. Qingyan 87-114) were studied in hydroponic solution culture. The Cd concentration higher than 10 μM significantly
decreased the root elongation and leaf chlorophyll contents of both plant species. The shoots of B. pekinensis had significantly higher concentrations of total and water-soluble Cd than B. chinensis. The roots of both species accumulated more Cd than the shoots in all the Cd treatments. Most of the Cd in the roots was
found in the cell walls. The shoot/root ratio of Cd concentrations in B. pekinensis was always greater than that in B. chinensis. But, the concentration and proportion of Cd in the cell walls in B. chinensis were higher than that in B. pekinensis. Cadmium treatments also increased the concentrations of total non-protein thiols (NPT) in the shoots of the both species.
A significant correlation was found between the concentrations of soluble Cd and NPT in plant shoots. 相似文献
8.
Elif Aylin Ozudogru Ergun Kaya Emrah Kirdok Saliha Issever-Ozturk 《In vitro cellular & developmental biology. Plant》2011,47(2):309-320
An efficient in vitro propagation protocol, applicable both to young and mature explants of two Thymus spp., results in genetically stable plantlets. In vitro-grown shoot tips of Thymus vulgaris L. were exposed to cytokinins (6-benzyladenine, kinetin, and thidiazuron) alone or in combination with auxins, gibberellic
acid (GA3) and/or silver nitrate in order to optimize in vitro shoot proliferation. Optimum shoot proliferation (97% regeneration rate, with 8.6 shoots produced per explant) was obtained
when semi-solid Murashige and Skoog (MS) medium was supplemented with 1 mg L−1 kinetin and 0.3 mg L−1 GA3. Rooting of the shoots was easily obtained on semi-solid MS medium that was either hormone-free or supplemented with auxins.
However, the best root apparatus (92.5% rooting rate, with 19 adventitious roots per shoot) developed on MS medium supplemented
with 0.05 mg L−1 2,4-dichlorophenoxyacetic acid. Genetic stability was confirmed in the in vitro-germinated mother plant as well as the shoots that underwent two, four, six, eight, or ten cycles of in vitro subculturing by random amplified polymorphic DNA (RAPD) analysis. When applied to the micropropagation of mature shoot tips
of T. longicaulis C. Presl subsp. longicaulis var. subisophyllus (Borbás) Jalas, the optimized in vitro propagation protocol resulted in a 97.5% shoot regeneration rate, with five shoots formed per explant, and 100% rooting.
Rooted plantlets of both species were transferred to 250-mL plastic pots and successfully acclimatized by gradually reducing
the relative humidity. 相似文献
9.
Yeonghoo Kim Joji Arihara Takuji Nakayama Norikazu Nakayama Shinji Shimada Kenji Usui 《Plant Growth Regulation》2004,44(1):87-92
Two gramineous species among wild plants, Echinochloa oryzicola Vasing and Setaria viridis (L.) Beauv., and Oryza sativa L. cv. Nipponbare were subjected to salt stress. The relative growth rate (RGR), Na content, photosynthetic rate, antioxidant enzymes activity (superoxide disumutase (SOD), catalase (CAT), ascorbate peroxidase (APx) and glutathione reductase (GR)), and malondialdehyde (MDA) content in leaves after NaCl treatment were studied. RGR significantly decreased in O. sativa more than in E. oryzicola and S. viridis. Comparatively salt-tolerant S. viridis showed higher growth rate, lower Na accumulation rate in leaves, higher photosynthetic rate, and induced more SOD, CAT, APx, and GR activity and lower increase of MDA content as compared to the salt-sensitive O. sativa. At the same time, the comparatively salt-tolerant E. oryzicola also showed higher growth rate, much lower Na accumulation and no observable increase of MDA content, even though the CAT and APx activities were not induced by salinity. These results suggested that the scavenging system induced by H2O2-mediated oxidative damage might, at least in part, play an important role in the mechanism of salt tolerance against cell toxicity of NaCl in some gramineous plants 相似文献
10.
Effect of salinity on Hyacinth bean, Lablab purpureus (HA-4 cultivar) was evaluated in 10-day old seedlings with 100–500 mM NaCl over 72 h of exposure. The stress reduced dry
and fresh weight, leaf surface area, root and shoot length, total chlorophyll, and RWC. Oxidative stress markers, H2O2, glutathione, TBARS, proline, ascorbic acid, total phenols, and total soluble sugar contents were significantly elevated.
Salinity enhanced antioxidant enzymes, POX, and GR activities and reduced that of CAT in concentration and time dependent
manner in leaves. Antioxidant enzymes in roots showed inverse relationship with concentration and time of exposure. Metabolic
enzyme β-amylase activity increased in both leaves and roots. Acid phosphatase decreased in leaves and elevated in roots.
Intensity of constitutive isozymes correlated with in vitro levels under stress, but the protein band patterns differed from
controls. Lablab showed reasonable tolerance up to 300 mM NaCl, but leaves and roots differed in their response. 相似文献
11.
Effects of exogenous salicylic acid (SA) on plant growth, contents of Na, K, Ca and Mg, activities of superoxide dismutase
(SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR)
and catalase (CAT), and contents of ascorbate and glutathione were investigated in tomato (Lycopersicon esculentum L.) plants treated with 100 mM NaCl. NaCl treatment significantly increased H2O2 content and lipid peroxidation indicated by accumulation of thiobarbituric acid reactive substances (TBARS). A foliar spray
of 1 mM SA significantly decreased lipid peroxidation caused by NaCl and improved the plant growth. This alleviation of NaCl
toxicity by SA was related to decreases in Na contents, increases in K and Mg contents in shoots and roots, and increases
in the activities of SOD, CAT, GPX and DHAR and the contents of ascorbate and glutathione. 相似文献
12.
Ni Chen Yan Liu Xin Liu Juan Chai Zhong Hu Guangqin Guo Heng Liu 《Plant Molecular Biology Reporter》2009,27(3):321-333
13.
Bei Wu Yun-He Li Jian-Yong Wu Qi-Zhu Chen Xia Huang Yun-Feng Chen Xue-Lin Huang 《Molecular biology reports》2011,38(5):3189-3194
14.
Mostafa Hojati Seyed Ali Mohammad Modarres-Sanavy Mojtaba Karimi Faezeh Ghanati 《Acta Physiologiae Plantarum》2011,33(1):105-112
An investigation was carried out to find out the extent of changes occurred in two safflower (Carthamus tinctorius L.) cultivars in response to water deficit stress. Two safflower cultivars namely IL.111 and Isfahan were used for the study.
Thirty days after sowing, plants were grown under soil moisture corresponding to 100, 85, 70 and 55% field capacity for next
30 days. Water deficit treatments significantly decreased the shoot length, shoot dry matter, root dry matter, relative growth
rate, leaf relative water content (LRWC) and leaf water potential (ΨW), whereas root length, root-to-shoot ratio, lipid peroxidation and antioxidant compounds such as ascorbic acid (AA), α-tocopherol
(α-Toc) and reduced glutathione (GSH) and superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), and peroxidase
(POX, EC 1.11.1.7) activities were increased. Water deficit stressed plants maintained higher levels of compounds and scavenging
enzymes. Significant differences were observed between cultivars and irrigation levels treatments. The cv. IL.111 could be
considered more tolerant to water stress than cv. Isfahan, registering greater biomass, LRWC and leaf water potential (ΨW), associated with high antioxidant activity. 相似文献
15.
Pratiksha Bhadauriya Radha Gupta Surendra Singh Prakash Singh Bisen 《World journal of microbiology & biotechnology》2008,24(1):139-141
n-Alkanes pattern in response to NaCl stress has been studied in the cyanobacterium Anabaena cylindrica. Saturated hydrocarbons were separated and identified by gas chromatography-mass spectrometry (GC-MS) using serially coupled
capillary column. Light chain n-alkanes in the range of C9–C17 (43%) and heavy chain n-alkanes in range of C17–C23 (34%) and C23–C31 (23%) were identified as the major components of total hydrocarbons in the NaCl adapted cells of A. cylindrica. In contrast, NaCl-untreated cells of A. cylindrica had dominance of only long chain n-alkanes in the range of C23–C31 comprising about 94% of its total n-alkanes. The persistence of high level (43%) of short chain n-alkanes (C9–C17) in NaCl adapted cells of A. cylindrica as compared to its negligible level (0.2%) in NaCl untreated counterpart clearly indicates that NaCl stress causes the A. cylindrica to shift towards the synthesis of short chain n-alkanes. 相似文献
16.
A. M. Vieitez E. Corredoira A. Ballester F. Muñoz J. Durán M. Ibarra 《Plant Cell, Tissue and Organ Culture》2009,98(2):135-145
North American oak species, with their characteristic strong episodic seasonal shoot growth, are highly problematic for clonal
micropropagation, resulting in the inability to achieve a stabilized shoot multiplication stage. The potential for initiating
and proliferating shoot cultures derived from Quercus alba, Q. bicolor and Q. rubra explants was investigated, and a micropropagation method for these species was developed. Branch segments from 6 to 7-year-old
trees were forced-flushed and the forced shoots were used as source of explants for culture initiation. A consistent shoot
multiplication stage was achieved, in 13 of the 15 genotypes established in vitro, although marked differences occurred in
explants from different genotypes/species. The control of efficient shoot multiplication involved the culture of decapitated
shoots in a stressful horizontal position on cytokinin-containing medium with a sequence of transfers within a 6-week subculture
cycle, which was beneficial to overcoming the episodic character of shoot growth. During each subculture cycle, the horizontally
placed explants were cultured on media containing 0.2 mg l−1 benzyladenine (BA) for 2 weeks with two successive transfers (2 weeks each) to fresh medium with 0.1 mg l−1 BA, giving a 6-week subculture cycle. The general appearance and vigor of Q. alba and Q. bicolor shoot cultures were improved by the inclusion of both 0.1 mg l−1 BA and 0.5 mg l−1 zeatin in the medium used for the second transfer within the 6-week subculture cycle. Addition of AgNO3 (3 mg l−1) to the shoot proliferation medium of Q. rubra had a significant positive effect on shoot development pattern by reducing deleterious symptoms, including shoot tip necrosis
and early senescence of leaves. The three species showed acceptable in vitro rooting rates by culturing microcuttings in medium
containing 25 mg l−1 indolebutyric acid for 48 h with subsequent transfer to auxin-free medium supplemented with 0.4% activated charcoal. Although
an initial 5-day dark period generally improved the rooting response, it was detrimental to the quality of regenerated plantlets.
However, activated charcoal stimulated not only the rooting frequencies, but it also enhanced plant quality, as evidenced
by root, shoot and leaf growth. 相似文献
17.
Ashish Kumar Srivastava Vinayak H. Lokhande Vikas Y. Patade Penna Suprasanna Rinaldi Sjahril Stanislaus Francis D’Souza 《Acta Physiologiae Plantarum》2010,32(6):1135-1144
The present study was aimed to evaluate the effect of different seed priming methods to enhance the sodium chloride (NaCl)
and polyethylene glycol-8000 (PEG-8000) stress tolerance in Indian mustard (Brassica juncea L.). Seeds subjected to different priming treatments such as water (hydro-priming), calcium chloride (CaCl2) (chemo-priming), and abscisic acid (ABA) (hormonal-priming) showed increased rate of germination as compared to non-primed
seeds. The primed and non-primed seeds were grown for 15 days and then the seedlings were independently subjected to iso-osmotic
salt (150 mM NaCl) or PEG-8000 (20%) stress. The different biochemical responses were studied 10 days after treatment. Under
NaCl and PEG stress, the dry weight and total chlorophyll content were higher in primed sets as compared to non-primed treatment
which was also evident by the phenotype of the seedlings. In general, the higher activities of superoxide dismutase and glutathione
reductase resulted in lower oxidative damage, in terms of malondialdehyde content, under NaCl and PEG stress in hydro-primed
set as compared to non-primed, ABA-, and CaCl2-primed treatments. Besides, the level of total phenolics and accumulation of osmolytes such as free proline, glycine betaine,
and total soluble sugars was also lower in hydro-primed set as compared to other primed and non-primed treatments. The study
thus suggests the use of hydro-priming as a simple and cost-effective strategy to alleviate the NaCl and PEG induced stress
in B. juncea. 相似文献
18.
In a glasshouse, Bemisia tabaci infestation largely reduced response of photosynthesis to irradiance and CO2 concentration of Mikania micrantha compared with the non-infested control (C) ones. The maximum irradiance-saturated photosynthetic rate (P
max) and saturation irradiance (SI) of the infested M. micrantha were only 21.3 % and 6.5 % of the C-plants, respectively. B. tabaci infestation led to the reduction of contents of chlorophyll and carotenoids in M. micrantha, which was accompanied with the decrease of actual photosystem 2 (PS2) efficiency (ΦPS2), efficiency of excitation energy capture by open PS2 reaction centres (Fv′/Fm′), electron transport rate (ETR), and photochemical quenching (qP). Moreover, superoxide dismutase and catalase activities significantly decreased while proline and glutathione contents significantly
increased in infested M. micrantha. Hence B. tabaci infestation not only induced direct damage of photosynthetic apparatus but also altered the antioxidant enzymes activities
in M. micrantha, which might as consequences accelerate senescence of this weed. 相似文献
19.
Filipendula ulmaria (L.) Maxim (meadowsweet) is a medicinal plant that is claimed to have several biological activities, including anti-tumor,
anti-carcinogenic, anti-oxidant, anti-coagulant, anti-ulcerogenic, anti-microbial, anti-arthritic, and immunomodulatory properties.
This report describes, for the first time, an efficient plant regeneration system for F. ulmaria via adventitious shoot development from leaf, petiole, and root explants cultured on Murashige and Skoog’s minimal organics
medium containing different concentrations of thidiazuron (TDZ), benzyladenine, and kinetin either alone or in combination
with different auxins. Relatively extensive/prolific shoot regeneration was observed in all three explant types with TDZ in
combination with indole-3-acetic acid (IAA). Gibberellic acid (GA3), TDZ, and IAA combinations were also tested. The best shoot proliferation was observed among root explants cultured on media
supplemented with 0.45 μM TDZ + 2.85 μM IAA + 1.44 μM GA3. Regenerated shoots were transferred to rooting media containing different concentrations of either IAA, indole-3-butyric
acid (IBA), naphthalene acetic acid, or 2,4-dichlorophenoxyacetic acid. Most shoots developed roots on medium with 2.46 μM
IBA. Rooted explants were transferred to vermiculite in Magenta containers for a 2-wk acclimatization period and then finally
to plastic pots containing potting soil. The plantlets in soil were kept in growth chambers for 2 wk before transferring to
greenhouse conditions. 相似文献
20.
AR Torres G Kaschuk GP Saridakis M Hungria 《World journal of microbiology & biotechnology》2012,28(4):1831-1835
Brazil has succeeded in sustaining production of soybean [Glycine max (L.) Merrill] by relying mainly on symbiotic N2 fixation, thanks to the selection and use in inoculants of very effective strains of Bradyrhizobium japonicum and Bradyrhizobium elkanii. It is desirable that rhizobial strains used in inoculants have stable genetic and physiological traits, but experience confirms
that rhizobial strains nodulating soybean often lose competitiveness in the field. In this study, soybean cultivar BR 16 was
single-inoculated with four B. japonicum strains (CIAT 88, CIAT 89, CIAT 104 and CIAT 105) under aseptic conditions. Forty colonies were isolated from nodules produced
by each strain. The progenitor strains, the isolates and four other commercially recommended strains were applied separately
to the same cultivar under controlled greenhouse conditions. We observed significant variability in nodulation, shoot dry
weight, shoot total N, nodule efficiency (total N mass over nodule mass) and BOX-PCR fingerprinting profiles between variant
and progenitor strains. Some variant strains resulted in significantly larger responses in terms of shoot total N, dry weight
and nodule efficiency, when compared to their progenitor strain. These results highlight the need for intermittent evaluation
of stock bacterial cultures to guarantee effective symbiosis after inoculation. Most importantly, it indicates that it is
possible to improve symbiotic effectiveness by screening rhizobial strains for higher N2 fixation capacity within the natural variability that can be found within each progenitor strain. 相似文献