Nutrient Solution Culture Research Articles

Effects of Al and Mn, Alone and in Combination, on Growth and Nutrient Status of Red Pine Seedlings Hydroponically Grown in Nutrient Culture Solution

Effects of Al and Mn, Alone and in Combination, on Growth and Nutrient Status of Red Pine Seedlings Hydroponically Grown in Nutrient Culture Solution

Effect of Ca/Al molar ratio on the growth of Cryptomeria japonica, Chamaecyparis obtusa and Chamaecyparis pisifera grown in nutrient solution culture and their critical point

Effect of Ca/Al molar ratio on the growth of Cryptomeria japonica, Chamaecyparis obtusa and Chamaecyparis pisifera grown in nutrient solution culture and their critical point

Growth and nutrient uptake responses of ‘Seolhyang’ strawberry to various ratios of ammonium to nitrate nitrogen in nutrient solution culture using inert media

� concentration in the petiole sap, EC and pH of the root substrate were quadratic, with a coefficients of R 2 = 0.99***, 0.98***, and 0.73*.

Nickel supplementation effect on the growth, urease activity and urea and nitrate concentrations in lettuce supplied with different nitrogen sources

Effect of nickel (Ni) in the nutrient solution on yield, N metabolism, and nitrate content of leafy vegetables is poorly understood. The aim of this nutrient solution culture experiment was to investigate the effects of Ni supplementation on the nitrogen (N) metabolism and growth of lettuce ( Lactuca sativa L. cv. Baker) with either urea or nitrate as the N source. Nickel supplement at 0.04 μM reduced urea toxicity to the urea-fed plants. Addition of Ni to the nutrient solution significantly increased the leaves and root growth of the urea-fed lettuce plants while it increased the growth of lettuce plants fed with nitrate only at N level of 20 mM. At N level of 20 mM, the leaves fresh weight of the urea-fed plants promoted by Ni supplement was comparable with the nitrate-fed plants untreated with Ni. Nickel supplementation increased the leaf total N concentrations in the urea-fed plants, although the nitrate-fed plants accumulated greater N in their leaves compared with urea treated plants at without Ni treatment. Nickel addition decreased the concentrations of leaf urea-N in the urea-fed plants and NO 3-N in the nitrate-fed plants. Nickel addition enhanced urease activity in the leaves of urea-fed plants. The results indicated Ni supplementation enhances the growth of the urea-fed lettuce plants while it has role in decreasing leaf nitrate concentration and thus, improving the health quality of the nitrate-fed plants.

Effects of phosphorus concentration on adaptive mechanisms of high- and low-P efficiency soybean genotypes when grown in solution

Low availability of phosphorus (P) in soil is a major constraint for crop production in agricultural ecosystems. Therefore, it is very important to explain the adaptive mechanism of crops under low P conditions. The response of high- and low-P efficient soybean (Glycine max L.) genotypes to various external P level was carried out in nutrient solution culture. Results showed that Dongnong1031 (low P-efficient genotype) undergoes major changes in terms of dry mass, root length, root number and root surface, while these response of Hai 616 (high P-efficient genotype) was lower after five weeks of growth. The higher P level in solution, the smaller difference between the two genotypes in these parameters. The amount of H+ released by root of Dongnong1031 was lower than that of Hai 616, except when supplied with 50 μmol external P. There was a positive relationship between RPAE (relative phosphorus absorption efficiency) and P concentration in shoot and root material at all P levels, irrespective of soybean genotype. An exponential relationship was found between PUE (phosphorus utilization efficiency) and P concentrations in shoots and roots. These results suggested that an increase in measured root parameters coupled with H+ release by roots were key mechanisms for soybean genotypes with high-P efficiency to cope with low P conditions when grown in solution. In order to best select high soybean genotype with high-P efficiency one should pay attention to PUE combined with high RPAE.

Differential responses of sweetpotato peroxidases to heavy metals

Oxidative stress is one of the major causes of damage in plants exposed to different types of environmental stress, including heavy metals. Accumulation of heavy metals in plants can disrupt many cellular functions and plant growth. To assess the contribution of oxidative stress to heavy metal toxicity in plants, young sweetpotato plants ( Ipomoea batatas) were treated with increasing concentrations of Cd, Cu and Zn, and grown in half Murashige and Skoog nutrient solution culture. Plant growth was significantly inhibited and internal metal content was increased in a dose-dependent manner for each metal. The generation of H 2O 2 in leaves and fibrous roots correlated positively with metal dose. The specific activity of peroxidases (PODs) in fibrous roots was markedly enhanced by metal treatment, whereas in leaves, activity was low and only slightly affected by metal treatment. Analysis of 13 POD genes revealed differential expression of PODs in response to heavy metals. Several genes for acidic PODs ( swpa2, swpa3 and swpa4) and basic PODs ( swpb1, swpb3 and swpab4) were strongly expressed under all metal treatment conditions in leaves or fibrous roots. The expression of swpa1 was increased in leaves and fibrous roots by Cd and Cu treatment, whereas swpb5 expression was reduced by all metals in fibrous roots. These results indicate that increased H 2O 2 levels in response to heavy metal stress are closely linked to an improved antioxidant defense capability mediated by POD.

Comparative Analysis of Six Triticum turgidum L. Subspecies for Acid and Aluminum Tolerance

The aluminum (Al) tolerance of hexaploid wheat and rye has been extensively studied. However, the Al tolerance of tetraploid wheat (Triticum turgidum L.), the AABB genome donor of hexaploid wheat, has not been well characterized. To understand the Al tolerance of tetraploid wheat and identify potentially new sources of tolerance to acidic soils, 254 Triticum turgidum wheat lines, including six subspecies of T. turdigum ssp. dicoccoides, ssp. dicoccon, ssp. carthlicum, ssp. turgidum, ssp. durum, and ssp. polinicum, were screened for acid and Al tolerance by measuring the root regenerate lengths and the tolerance indices in acid nutrient culture solution containing Al. Significant differences were observed either among or within tetraploid wheat subspecies on the RRL (root regenerate lengths). The orders for average RRL among subspecies in pH 7.00, pH 4.50 and pH 4.50 + 50 μmol L −1 Al 3+ were carthlicum ≥ turgidum ≥durum≥ dicoccoides ≥ polinicum ≥ dicoccon, carthlicum ≥ turgidum ≥ durum ≥ polinicum≥ dicoccon ≥ dicoccoides and durum ≥ dicoccoides ≥ carthlicum ≥ turgidum ≥ polinicum ≥dicoccon, respectively. Significant difference was also observed on the root acid tolerance index (RTI1) and root Al tolerance index (RTI2) either among or within tetraploid wheat subspecies. Compared to RTI2, RTI1 varied in a wide range but with large value. The orders of the average RTI1 and RTI2 among subspecies were polinicum ≥ dicoccon ≥ carthlicum ≥ dicoccoides ≥ turgidum ≥ durum, and dicoccoides ≥ durum ≥ turgidum ≥ polinicum ≥ carthlicum ≥ dicoccon, respectively. Significant difference on acid and Al tolerance was existed either among or within subspecies. Some potentially tolerance germplasms different from those derived from hexaploid wheat, including 42 acid tolerance and 41 Al tolerance lines, were identified in 254 tetraploid wheat lines. They provide new sources for hexaploid wheat acid and Al tolerance improvement.

Effects of Exogenous Spermidine on Reactive Oxygen Levels and Antioxidative System of Tomato Seedling under Polyethlene Glycol Stress*

Two different drought-tolerant tomato cultivars were investigated under drought stress induced by 7.5% polyethylene glycol (PEG6000) in a nutrient solution culture system. The results showed that exogenous spermidine (Spd) (0.1 mmol L-1 ) treatment decreased O2-· production rate, and MDA and H2O2 contents, raised SOD, POD, CAT, APX and GR activities in the seedlings, and had no effect on MDHAR and DHAR activities. Spd treatment of ‘Huangguan’ seedlings with lower drought-resistance was more effective than that of ‘Maofen No. 802’ seedlings with stronger drought-resistance. It indicated that exogenous Spd treatment could to enhance the activities of some antioxidant enzymes and the contents of antioxidant substances, restrain embrane lipid peroxidation, reduce ROS levels and finally enhance the tolerance of tomato seedlings to drought environments. Fig 4, Ref 32

Hydrophilic interaction LC combined with electrospray MS for highly sensitive analysis of underivatized amino acids in rhizosphere research

Analysis of underivatized amino acids is challenging regarding the separation as well as the detection of these small polar analytes. Hydrophilic interaction LC using a 2.1x150 mm ZIC (ZIC, zwitterionic)-hydrophilic interaction LC from SeQuant as stationary phase with 1% v/v formic acid in water and ACN as eluents was combined with MS/MS in multiple reaction monitoring mode for the separation and the detection of 16 underivatized amino acids. Regression coefficients of eight or seven point calibrations varied from 0.9454 to 0.9993. Absolute LODs and LOQ (on column) were in the fmol range (0.1-12 and 0.4-41 fmol, respectively). A fast screening method of 19 min total runtime has been developed offering applicability to samples from rhizosphere studies--characterized by low analyte concentrations and complex matrices. A successful application to the analysis of tyrosine in samples from soil adsorption experiments is presented as well as an evaluated enrichment procedure for amino acids derived from plant culture in nutrient solution.

EFFECTS OF P DEFICIENCY ON PROTECTIVE ENZYME ACTIVITY AND MEMBRANE LIPID PEROXIDATION IN DIFFERENT TOMATO GENOTYPES

The protective enzyme activity and membrane lipid peroxidation in leaves at different P levels in nine tomato genotypes collected from the world were studied in nutrient solution culture. Phosphorus deficiency decreased leaf Chl contents. Compared with the control, there was a slight change of catalase activities in tomato seedlings under P deficiency, but superoxide dismutase activities, peroxidase activities and membrane-lipid peroxidation contents increased in phosphorus deficiency seedlings. There were differences in SOD activities, POD activities and MDA contents among tomato genotypes. The SOD activities under P deficiency stress in No. 4 and No. 54 increased more than that in No. 46, No. 2738 and No. 37 as compared with control seedlings. POD activities under P deficiency stress in No. 27, No. 37 and No. 46 increased more than that in No. 4, No. 25 and No. 2738. MDA contents under P deficiency stress in No. 2, No. 4 and No. 2738 increased more than that in No. 25, No. 27 and No. 37 as compared with control seedlings. These results indicated that the possible role of SOD activities, POD activities and MDA contents as anti-oxidant protector systems for tomato plants under phosphorus deficiency. Moreover, they suggest the possibility of using these enzyme activities as an additional screening criterion for detecting phosphorus efficiency in tomato genotypes.

Phytotoxicity and Accumulation of Lead in Australian Native Vegetation

Lead (Pb) is a wide spread contaminant in the terrestrial landscape. It is highly detrimental to plant and animal life and possesses no known biologic function. Yet there is a paucity of reliable information available on the response of Australian and other plant species to Pb exposure at phytotoxic doses. In this study, the response of three Australian native grass species and two tree species to Pb in nutrient solution culture was investigated. Plants were exposed to average Pb concentrations ranging from 0.020 to 15.2 microM. The plant species included Acacia decurrens, Austrodanthonia richardsonii, Bothriochloa macra, Eucalyptus camaldulensis, and Dichanthium sericeum. Few foliar symptoms were evident in any plant species, although some discolouration in young leaves of E. camaldulensis was evident from 1 microM, and B. macra showed pronounced reddening at the highest treatments. The most tolerant plant species studied based on solution EC(50, roots) (microM) results was B. macra (7.0 +/- 0.2), followed by A. decurrens (3.9 +/- 0.2), D. sericeum (2.9 +/- 0.3), E. camaldulensis (1.1 +/- 0.3), and A. richardsonii (0.4). A hazardous concentration value (HC(5)) (n = 9) for soil solution was estimated to be 0.16 microM. A. richardsonii was highly sensitive to Pb and possessed little ability to restrict Pb translocation to its shoots. B. macra was able to tolerate high root (3924 mg kg(-1)) and shoot (743.0 mg kg(-1)) Pb concentrations. A. decurrens excluded Pb from it shoots. The high tolerance of A. decurrens to Pb and limited translocation to shoots indicates it may be useful in revegetation of Pb-contaminated soils.

Growth and Chlorophyll Content of Canola Plants Supplied with Urea and Ammonium Nitrate in Response to Various Nickel Levels

Both the beneficial and the adverse effects of various nickel level supplements on growth and chlorophyll content of canola plants were evaluated while either urea or ammonium nitrate was supplied as the sole N source in the nutrient solutions. This study was arranged in completely randomized with three replications. Treatments included nutrient solution cultures containing urea and ammonium nitrate at the rate of 84 mg N L-1 separately as nitrogen sources with four nickel levels as NiSO4.6H2O at the rates of 0, 0.01, 0.05 and 0.1 mg Ni L-1. Plants were allowed to grow for 6 weeks then leaves chlorophyll content and shoots and roots fresh and dry weight were determined. Both plant growth and leaves chlorophyll content of the urea-fed plants increased significantly with the increase in nickel content up to 0.1 mg Ni L-1. However, root fresh and dry weight increased up to 0.01 mg Ni L-1 and started to decrease with further increase in solutions nickel content. Nickel did not affect these parameters with plants supplied with ammonium nitrate significantly. In these plants, the optimum nickel level for shoot growth and leaves chlorophyll content was 0.05 mg L-1 and for root fresh and dry weight was 0.01 mg Ni L-1. Further increase in Ni concentration reduced growth. As a whole, plants received urea plus nickel performed better than those received ammonium nitrate plus nickel.

Potassium Level and Physiological Response and Fruit Quality in Hydroponically Grown Tomato

Tomato (Lycopersicon esculentum Mill.) is a popular vegetable in many parts of the world. The role of potassium in plant metabolism, growth, and development and its significance in production of marketable fruit and on fruit flavor and visual appearance are known. It is not clear how hybrids and nonhybrids, which differ greatly in growth and yield, respond to potassium. The tomato cvs. Pant T-3 (nonhybrid) and Avinash-2 (hybrid) were treated with three levels of potassium at 200, 300, and 400 mg·L−1 in Hoagland nutrient solution culture. ‘Avinash-2’ produced more fruit than the nonhybrid cv. Pant T-3. Fruit production increased as potassium concentration increased in both cvs., but magnitude of yield was greater for the nonhybrid cultivar. The highest leaf chlorophyll content, photosynthetic rate, and potassium contents were in plants treated with 300 mg·L−1 K in both cultivars. There was significant improvement in protein, ascorbic acid, lycopene, total soluble solids, reducing sugar levels, and titratable acidity in fruit as K concentration increased up to 300 mg·L−1. The cv. Pant T-3 responded better to K concentration than did ‘Avinash-2’. Application of adequate potassium is necessary to improve yield and quality of tomato and K availability had a role in improving fruit production and quality of a nonhybrid tomato more so than in a hybrid tomato cultivar.

Nitrogen Fixation, Ureide, and Nitrate Accumulation Responses to Soybean Aphid Injury in Glycine max

ABSTRACT There is little information available about soybean aphid (Aphis glycines Matsumura) effects on the physiology and mineral nutrition of soybean (Glycine max [L.] merr.). Controlled-environment studies were conducted to measure soybean aphid infestation effects on dry weight, nitrogen (N) fixation, ureide-N, and nitrate-N concentration and accumulation. Plants grown in perlite using –N nutrient solution culture were infested at the 3rd trifoliolate (V3) stage and measured for N fixation, nodule characteristics, and ureide-N concentration at the full pod (R4) stage. When compared to uninfested control plants, aphid infestation reduced total nodule volume per plant by 34%, nodule leghemoglobin per plant by 31%, plant N fixation rate by 80% and shoot ureide-N concentration by 20%. Soil-grown plants were infested at the first trifoliolate (V1) stage and shoots were measured for dry weight, nitrate-N, and ureide-N at the full bloom (R2) stage. Infestation reduced shoot dry weight by 63%, increased nitrate-N concentration by 75%, but did not significantly affect ureide-N concentration. Because nutrient concentration is a single-point measurement that results from the integration of two dynamic processes, nutrient accumulation and dry matter production, we conclude that aphid-induced reductions in N fixation, coupled with decreased dry weight accumulation, caused shoot ureide-N concentration to remain unchanged in aphid-injured plants when compared to uninfested plants. Because nitrate-N concentration was greater in aphid-damaged shoot tissue, we further conclude that nitrate-N accumulation was less sensitive to aphid injury than dry weight accumulation.

Growth and Phosphorus Uptake of Three Riparian Grass Species

Riparian buffers can significantly reduce sediment‐bound P entering surface water, but control of dissolved P inputs is more challenging. Because plant roots remove P from soil solution, it follows that plant uptake can reduce dissolved P losses. We evaluated P uptake of smooth bromegrass (Bromus inermis Leyss.), reed canarygrass (Phalaris arundinacea L.), and switchgrass (Panicum virgatum L.) grown in a flowing nutrient solution culture system with P concentrations of 1 or 100 μmol L−1 Plants were destructively sampled at approximately 0, 26, 40, and 53 days after transplanting (DAT). In a separate, concurrent experiment, we simulated the effect of an inflow of runoff with low or high dissolved P by switching a subset of pots approximately 40 DAT. When grown in 1 μmol L−1 P solution, shoot dry matter (DM) yield increased in the order bromegrass < switchgrass < canarygrass. When grown in 100 μmol L−1 P solution, shoot DM yield increased in the order bromegrass = canarygrass < switchgrass. Shoot P content was correlated with shoot DM yield; however, switchgrass was the only species that had higher P content in plants grown in 100 μmol L−1 P solution than in 1 μmol L−1 P solution. When solution P concentration was abruptly increased or decreased, P uptake was affected more than plant growth. Shoot P concentration of canarygrass increased more than 3.5‐fold when the plants were switched from 1 μmol L−1 P solution to 100 μmol L−1 P solution. Shoot P concentration of switchgrass followed the same trend. The results of this solution‐culture experiment suggest that canarygrass and switchgrass would more effectively deplete dissolved P than would bromegrass.

Effects of Phosphorus Deficiency on Growth and Nitrogen Fixation of Soybean after Nodule Formation

Phosphorus had a key role in soybean growth, however, it is very different to separate the role in soybean growth from that in nodule function. The research was conducted to elucidate the effects of phosphorus deficiency on growth and nitrogen fixation after nodule formation in soybean. Soybean seedlings were cultivated in nutrient solution culture with normal phosphorus concentration (30 μmol L-1), which was shifted to 0 and 4 μmol L-1 after nodule formation resulting in phosphorus deficience for soybean plants. The results showed that phosphorus deficiency negatively influenced soybean plant growth at the ninth day of phosphorus deficiency treatment and nitrogen fixation at the beginning of the treatment. The nodule number increased by 11.8%, 15.4%, and 20.0%, respectively in 0, 4, and 30 μmol L?1 phosphorus treatments at the ninth day of treatment compared with that at the third day. Leghemoglobin concentration per gram of plant and per nodule biomass increased with phosphorus concentration increase. These suggested that phosphorus deficiency affected significantly nodule development and nitrogen fixation when soybean plants formed sufficient nodule.

Changes of photosynthetic activities of maize (Zea mays L.) seedlings in response to cadmium stress

Maize (Zea mays L.) seedlings were grown in nutrient solution culture containing 0, 5, and 20 μM cadmium (Cd) and the effects on various aspects of photosynthesis were investigated after 24, 48, 96 and 168 h of Cd treatments. Photosynthetic rate (P N) decreased after 48 h of 20 μM Cd and 96 h of 5μM Cd addition, respectively. Chl a and total Chl content in leaves declined under 48 h of Cd exposure. Chl b content decreased on extending the period of Cd exposure to 96 h. The maximum quantum efficiency and potential photosynthetic capacity of PSII, indicated by Fv/Fm and Fv/Fo, respectively, were depressed after 96 h onset of Cd exposure. After 48 h of 5μM Cd and 24 h of 20 μM Cd treatments, the activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco, EC 4.1.39) and phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31) in the leaves started to decrease, respectively. We found that the limitation of photosynthetic capacity in Cd stressed maize leaves was associated with Cd toxicity on the light and the dark stages. However, Cd stress initially reduced the activities of Rubisco and PEPC and subsequently affected the PSII electron transfer, suggesting that the Calvin cycle reactions in maize plants are the primary target of the Cd toxic effect rather than PSII.

Toxic effects of Cu 2+ on growth, nutrition, root morphology, and distribution of Cu in roots of Sabi grass

Sabi grass ( Urochloa mosambicensis (Hack.) Dandy) (a C4 species of Poaceae) is commonly used to revegetate disturbed sites in low-rainfall environments, but comparatively little is known regarding copper (Cu) toxicity in this species. A dilute nutrient solution culture experiment was conducted for 10 d to examine the effects of elevated Cu 2+ activities ({Cu 2+}) on the growth of Sabi grass. Growth was inhibited by high Cu in solution, with a 50% reduction in the relative fresh mass occurring at 1.0 μM {Cu 2+} for the roots and 1.2 μM {Cu 2+} for the shoots. In solutions containing 1.2–1.9 μM {Cu 2+}, many of the roots ruptured due to the tearing and separation of the rhizodermis and outer cortex from the underlying tissues. Transmission electron microscopy revealed that Cu-rich deposits were found to accumulate predominantly within vacuoles. Due to limited translocation of Cu from the roots to the shoots, phytotoxicity is likely to be more of a problem in remediation of Cu-toxic sites than is Cu toxicity of fauna consuming the above-ground biomass.

Aluminium tolerance and high phosphorus efficiency helps Stylosanthes better adapt to low-P acid soils

Stylosanthes spp. (stylo) is one of the most important pasture legumes used in a wide range of agricultural systems on acid soils, where aluminium (Al) toxicity and phosphorus (P) deficiency are two major limiting factors for plant growth. However, physiological mechanisms of stylo adaptation to acid soils are not understood. Twelve stylo genotypes were surveyed under field conditions, followed by sand and nutrient solution culture experiments to investigate possible physiological mechanisms of stylo adaptation to low-P acid soils. Stylo genotypes varied substantially in growth and P uptake in low P conditions in the field. Three genotypes contrasting in P efficiency were selected for experiments in nutrient solution and sand culture to examine their Al tolerance and ability to utilize different P sources, including Ca-P, K-P, Al-P, Fe-P and phytate-P. Among the three tested genotypes, the P-efficient genotype 'TPRC2001-1' had higher Al tolerance than the P-inefficient genotype 'Fine-stem' as indicated by relative tap root length and haematoxylin staining. The three genotypes differed in their ability to utilize different P sources. The P-efficient genotype, 'TPRC2001-1', had superior ability to utilize phytate-P. The findings suggest that possible physiological mechanisms of stylo adaptation to low-P acid soils might involve superior ability of plant roots to tolerate Al toxicity and to utilize organic P and Al-P.

Effects of Se on the uptake of essential elements in Pteris vittata L.

Selenium has been proven to be an antioxidant in plants at low dosages. To understand better the mechanisms of Se toxicity and benefit to plants, more investigations about effects of Se on the uptake of essential elements in plants would be desirable. In this study, hydroponic (nutrient solution culture) and pot (soil culture) experiments were simultaneously conducted to investigate the effects of Se on the uptake and distribution of essential elements in Pteris vittata. L (Chinese brake fern), an arsenic (As)-hyperaccumulator and a selenium (Se)-accumulator. Chinese brake fern took up much more Se in nutrient solution culture than in soil culture, with the highest Se content recorded as 1,573 mg kg(-1) in the roots, demonstrating remarkable tolerance to Se. In soil culture, Chinese brake fern also accumulated high content of Se, with the highest content measured as 81 mg kg(-1) and 233 mg kg(-1), in the fronds and roots, respectively. In soil culture, the addition of Se suppressed the uptake of most measured elements, including magnesium (Mg), potassium (K), phosphorus (P), iron (Fe), copper (Cu) and zinc (Zn). In nutrient solution culture, when the Se content in the tissues of Chinese brake fern was relatively low, the supplementation of Se suppressed the uptake of most essential elements; however, with the increase of Se content, stimulation effects of Se on the uptake of Ca, Mg, K were observed. An initial decrease followed by a rapid increase of Fe content in the fronds of Chinese brake fern was found with Se addition and tissue Se content increasing in nutrient solution culture, suggesting antagonistic and synergic roles of Se on these elements under low and high Se exposure, respectively. We suggest that Ca, Mg, K may be involved in the tolerance mechanism of Se, and that the regulation of Fe accumulation by Se in the fronds might be partially due to the dual effects of Se on Chinese brake fern.