scholarly journals Iron Deficiency Induced Changes in Iron Reductase Activity in Papaya Roots

2002 ◽  
Vol 127 (2) ◽  
pp. 184-187 ◽  
Author(s):  
Thomas E. Marler ◽  
Ruben dela Cruz ◽  
Andrea L. Blas
Keyword(s):  
Glycine Max ◽  
Iron Deficiency ◽  
Carica Papaya ◽  
Reductase Activity ◽  
Fe Deficiency ◽  
Root Tip ◽  
Root Tips ◽  
Soybean Line ◽  
Induced Changes ◽  
Iron Reductase

Four papaya (Carica papaya L.) cultivars were cultured aeroponically or in perlite to determine the magnitude, timing, and root locality of Fe reductase induced by Fe deficiency. Five soybean [Glycine max (L.) Merrill] lines with a known range of Fe-deficiency chlorosis scores were cultured in perlite for comparison. Speed of inducement of Fe reductase activity was determined in plants cultured without Fe for 0 to 17 days. Location of Fe reductase activity was determined by sectioning roots from the tip to 60 to 70 mm proximal to the root tip from plants cultured without Fe for 16 to 19 days. The Fe reductase system was induced in all papaya cultivars after 7 to 11 days without Fe, and activity increased through 17 days. Iron reductase activity in all papaya cultivars was comparable to the most tolerant soybean line. The zone of highest activity was the apical 10 mm of roots. These results indicate that papaya roots are highly efficient in induced Fe reductase activity. The highest activity in root tips underscores the importance of maintaining a healthy, continually growing root system with numerous growing points when culturing papaya in alkaline substrates.

scholarly journals Iron Deficiency Induced Changes in Chlorophyll and Ferric Reductase Activity Asian Pear Rootstocks (Pyrus spp.) with Hydroponics

2005 ◽  
Vol 43 (3) ◽  
pp. 173-180
Author(s):  
Chunhui MA ◽  
Kenji TANABE ◽  
Akihiro ITAI ◽  
Yuanwen TENG ◽  
Jong-Pil CHUN
Keyword(s):  
Iron Deficiency ◽  
Reductase Activity ◽  
Ferric Reductase ◽  
Asian Pear ◽  
Induced Changes

scholarly journals Ayçiçeği Genotiplerinin Demir Noksanlığına Karşı Tolerans Düzeylerinin Belirlenmesi

2017 ◽  
Vol 5 (11) ◽  
pp. 1323
Author(s):  
Ayfer Alkan Torun ◽  
Halil Erdem ◽  
Mustafa Bülent Torun
Keyword(s):  
Iron Deficiency ◽  
Dry Matter ◽  
Ph Value ◽  
Reductase Activity ◽  
Chlorophyll Concentration ◽  
Fe Deficiency ◽  
Dry Matter Yield ◽  
Nutritional Disorder ◽  
Spad Value ◽  
Yield And Quality

Iron deficiency (Fe) is an important nutritional disorder of plants and humans worldwide including Turkey. Sunflower is known as a Fe sensitive crop and its deficiency leads to severe yield and quality losses. In this study, the sensitivity of different sunflower genotypes to Fe deficiency was determined. For this purpose, sunflower genotypes TR-6149-SA, TR-3080 and 6480 were grown either without Fe (0 µmol) or with Fe (100 µmol) hydroponically. At the end of experiment symptom grade, SPAD value, chlorophyll concentration, shoot dry matter yield, Fe-reductase activity, shoot Fe concentration and pH value of growth medium were measured. It was found out that Fe uptake and Fe reductase activity were the most important factors determining the Fe-deficiency tolerance of a genotype. In the deficiency of Fe conditions, the activity of Fe reductase enzyme in the roots was found higher in the genotype of TR-3080 compared to the other genotypes. The results revealed that the genotypic responses to the different Fe concentrations applied are significantly different and Fe reductase enzyme activity may play an important role in amelioration of iron deficiency.

scholarly journals Responses of tomato (Solanum lycopersicum L.) plants to iron deficiency in the root zone

2019 ◽  
Vol 31 (1) ◽  
pp. 223-234
Author(s):  
María Rocío Jiménez ◽  
Laura Casanova ◽  
Teresa Saavedra ◽  
Florinda Gama ◽  
María Paz Suárez ◽  
...  
Keyword(s):  
Iron Deficiency ◽  
Chlorophyll Content ◽  
Solanum Lycopersicum ◽  
Root Zone ◽  
Reductase Activity ◽  
Chlorophyll Concentration ◽  
Root Tip ◽  
Tomato Plants ◽  
Young Leaves ◽  
Root Swelling

AbstractIron deficiency induces a yellowing in the aerial part of plants, known as iron chlorosis, and reduces the growth, yield, and quality of the fruits. Understanding plant response to iron deficiency is essential for agronomic management. This study decoded the temporal response of tomato plants (Solanum lycopersicum L.) to iron deficiency by quantifying different vegetative parameters. Subapical root swelling in the first 2.0 mm and several shoot and root growth parameters were measured in plants grown in a nutrient solution with and without Fe, on different dates designated as days after transplantation (DAT). Correlations between the total chlorophyll concentration in young leaves and 22 morphological and physiological parameters were also calculated. The plants grown in the absence of Fe had a higher number of secondary roots at 3 DAT, compared to control plants. On the same date, subapical root swelling was also observed, particularly at 1.5 and 2.0 mm from the root tip. Those plants also had a lower chlorophyll content in young leaves and a higher ferric-chelate reductase activity (FCR; EC 1.16.1.17) in the roots. At 9 DAT, the overall vegetative performance (plant height, fresh weight of stems and leaves) was negatively affected. At the end of the experiment (14 DAT), significant correlations were found between chlorophyll and the studied parameters. In conclusion, tomato plants experienced a cascade of responses to Fe deficiency throughout nine days: firstly, root lateralization increased; later, root swelling was observed, and a decrease in leaf chlorophyll content was registered associated with an increase in root FCR. At the end, the biomass of tomato plants decreased.

Effects of Cd and Pb in sugar beet plants grown in nutrient solution: induced Fe deficiency and growth inhibition

2002 ◽  
Vol 29 (12) ◽  
pp. 1453 ◽  
Author(s):  
Ajmi Larbi ◽  
Fermín Morales ◽  
Anunciación Abadía ◽  
Yolanda Gogorcena ◽  
Juan J. Lucena ◽  
...  
Keyword(s):  
Sugar Beet ◽  
Reductase Activity ◽  
Chemical Species ◽  
Dry Mass ◽  
Fe Deficiency ◽  
Nutrient Concentrations ◽  
Chloride Salt ◽  
Root Tips ◽  
Chl A ◽  
Fresh And Dry Mass

Effects of Cd and Pb toxicity were investigated in sugar beet (Beta vulgaris L.) grown in hydroponics under growth-chamber-controlled conditions. Chemical speciation calculations were used to estimate the chemical species in equilibrium. Cd, used as chloride salt or chelated to EDTA, decreased fresh and dry mass of both root and shoot, and increased root / shoot ratios. Plants developed few brownish roots with short laterals. Cd decreased N, P, Mg, K, Mn, Cu and Zn uptake, and facilitated Ca uptake. Leaves of plants treated with 10 or 50 μM Cd–EDTA and 10 μM CdCl2 developed symptoms of Fe deficiency. These symptoms included decreased leaf chlorophyll (Chl) and carotenoid concentrations, increased carotenoid / Chl and Chl a/b ratios, de-epoxidation of violaxanthin cycle pigments, and decreased photosynthetic rates and PSII efficiency. Plants treated with 50 μM CdCl2, however, had decreased growth but did not show marked leaf Fe-deficiency symptoms. All Cd treatments increased Fe(III)-chelate reductase activity in root tips, although Fe concentrations in shoots were similar to those found in control plants. Pb chelated with EDTA induced visual symptoms only at concentrations of 2 mM. Leaves of Pb-treated plants remained green and their edges were rolled inwards. Pb increased root fresh and dry mass with no changes in shoot mass, therefore increasing the root / shoot ratio. Changes in plant nutrient concentrations with Pb were only minor, although leaf Cu levels approached critical deficiency levels. No symptoms of Fe deficiency were apparent in leaves. Root tips of Pb-treated plants, however, had increased Fe(III)-chelate reductase activities.

EFFECT OF IRON DEFICIENCY STRESS ON IRON-REDUCTASE ACTIVITY AT PLASMALEMMA OF APPLE ROOT CELLS

2002 ◽  
Vol 25 (11) ◽  
pp. 2535-2544
Author(s):  
Zhen Hai Han ◽  
Jing-Tao Zhu ◽  
Qian Wang ◽  
Xue-Feng Xu
Keyword(s):  
Iron Deficiency ◽  
Reductase Activity ◽  
Root Cells ◽  
Iron Reductase

Immunogold localization of calmodulin in root caps of the maize Cultivar Merit

1990 ◽  
Vol 48 (3) ◽  
pp. 674-675
Author(s):  
P.T. Nguyen ◽  
C. Uphoff ◽  
C.L. Stinemetz
Keyword(s):  
Calcium Binding ◽  
Calcium Transport ◽  
Primary Role ◽  
Immunogold Localization ◽  
Root Tips ◽  
Electrical Currents ◽  
Considerable Evidence ◽  
Maize Cultivar ◽  
Gravity Response ◽  
Induced Changes

Considerable evidence suggest that the calcium-binding protein calmodulin (CaM) may mediate calcium action and/or transport important in the gravity response of plants. Calmodulin is present in both shoots and roots and is capable of regulating calcium transport in plant vesicles. In roots calmodulin is concentrated in the tip, the gravisensing region of the root; and is reported to be closely associated with amyloplasts, organelles suggested to play a primary role in gravi-perception. Inhibitors of CaM such as chlorpromazine, calmidazolium, and compound 48/80 interfere with the gravitropic response of both snoots and roots. The magnitude of the inhibition corresponded well with the extent to which the drug binds to endogenous CaM. Compound 48/80 and calmidazolium block gravi-induced changes in electrical currents across root tips, a phenomenon thought to be associated with the sensing of the gravity stimulus.In this study, we have investigated the subcellular distribution of CaM in graviresponsive and non-graviresponsive root caps of the maize cultivar Merit.

COPPER AND ZINC INDUCED CHANGES IN SOYBEAN (Glycine max (L.) Merr.)

1970 ◽  
pp. 09
Author(s):  
K. SANKAR GANESH ◽  
P. SUNDARAMOORTHY
Keyword(s):  
Heavy Metals ◽  
Glycine Max ◽  
Aquatic Environment ◽  
Morphological Traits ◽  
Industrial Activities ◽  
Copper And Zinc ◽  
Glycine Max L ◽  
Zinc Concentrations ◽  
Induced Changes

Heavy metals are one of the most important pollutants released to the aquatic environment by the various industrial activities. The use of these wastewater for irrigation results accumulation of heavy metals in soil and plants. So, the present investigation deals with the various concentrations (0, 5, 10, 25, 50, 100, 200 and 300 mg/l) of copper and zinc on germination studies of soybean. The different concentrations of copper and zinc were used for germination studies. The seedlings were allowed to grow upto seven days. The studied morphological traits increased at 5 mg/l concentration and these parameters are gradually decreased with the increase of copper and zinc concentrations.

Histochemical Examination of Invertase Activities in the Growing Tip of the Plant Root

2017 ◽  
Vol 10 (1) ◽  
pp. 35-45
Author(s):  
N.F. Lunkova ◽  
N.A. Burmistrova ◽  
M.S. Krasavina
Keyword(s):  
Plant Root ◽  
Invertase Activity ◽  
Root Tip ◽  
Elongation Zone ◽  
Root Tips ◽  
Phloem Unloading ◽  
Meristem Cell ◽  
Transition To Elongation ◽  
Different Tissues

Background:A growing part of the root is one of the most active sinks for sucrose coming from source leaves through the phloem. In the root, sucrose is unloaded from conducting bundles and is distributed among the surrounding cells. To be involved in the metabolism, sucrose should disintegrate into hexoses by means of degrading enzymes.Aims:The aim of this research was to explore the possibility of the involvement of one such enzymes, invertase, in phloem unloading as well as distribution of its activity in the functionally different tissues of the plant root tips.Method:To estimate the enzyme activities in root tissues, we applied two techniques: the histochemical method using nitro blue tetrazolium. The localization of phloem unloading was studied with carboxyfluorescein, a fluorescent marker for symplastic transport.Results:Invertase activity was not detected in the apical part of the meristem. It appeared only between the basal part of this zone and the beginning of the elongation zone. There is the root phloem unloading in that area. Invertase activity increased with increasing the distance from the root tip and reached the highest values in the region of cell transition to elongation and in the elongation zone. The activities of the enzyme varied in different tissues of the same zone and sometimes in the neighboring cells of the same tissue. Biochemical determination of invertase activity was made in the maize root segments coincident to the zones of meristem, cell elongation and differentiation. The results of both methods of determination of invertase activity were in agreement.Conclusion:It was concluded that phloem unloading correlated with invertase activity, possibly because of the activation of invertase by unloaded sucrose. Invertase is one of the factors involved in the processes preparing the cells for their transition to elongation because the concentration of osmotically active hexoses increases after cleavage of sucrose, that stimulates water entry into the cells, which is necessary for elongation growth.

scholarly journals Effect of earthworms on mycorrhization, root morphology and biomass of silver fir seedlings inoculated with black summer truffle (Tuber aestivum Vittad.)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tina Unuk Nahberger ◽  
Gian Maria Niccolò Benucci ◽  
Hojka Kraigher ◽  
Tine Grebenc
Keyword(s):  
Root System ◽  
Root Biomass ◽  
Fine Root ◽  
Abies Alba ◽  
Fine Root Biomass ◽  
Root Tip ◽  
Silver Fir ◽  
Tuber Aestivum ◽  
Root Tips ◽  
Root Parameters

AbstractSpecies of the genus Tuber have gained a lot of attention in recent decades due to their aromatic hypogenous fruitbodies, which can bring high prices on the market. The tendency in truffle production is to infect oak, hazel, beech, etc. in greenhouse conditions. We aimed to show whether silver fir (Abies alba Mill.) can be an appropriate host partner for commercial mycorrhization with truffles, and how earthworms in the inoculation substrate would affect the mycorrhization dynamics. Silver fir seedlings inoculated with Tuber. aestivum were analyzed for root system parameters and mycorrhization, how earthworms affect the bare root system, and if mycorrhization parameters change when earthworms are added to the inoculation substrate. Seedlings were analyzed 6 and 12 months after spore inoculation. Mycorrhization with or without earthworms revealed contrasting effects on fine root biomass and morphology of silver fir seedlings. Only a few of the assessed fine root parameters showed statistically significant response, namely higher fine root biomass and fine root tip density in inoculated seedlings without earthworms 6 months after inoculation, lower fine root tip density when earthworms were added, the specific root tip density increased in inoculated seedlings without earthworms 12 months after inoculation, and general negative effect of earthworm on branching density. Silver fir was confirmed as a suitable host partner for commercial mycorrhization with truffles, with 6% and 35% mycorrhization 6 months after inoculation and between 36% and 55% mycorrhization 12 months after inoculation. The effect of earthworms on mycorrhization of silver fir with Tuber aestivum was positive only after 6 months of mycorrhization, while this effect disappeared and turned insignificantly negative after 12 months due to the secondary effect of grazing on ectomycorrhizal root tips.

scholarly journals Molecular Identification of Ectomycorrhizal Mycelium in Soil Horizons

2003 ◽  
Vol 69 (1) ◽  
pp. 327-333 ◽  
Author(s):  
Renske Landeweert ◽  
Paula Leeflang ◽  
Thom W. Kuyper ◽  
Ellis Hoffland ◽  
Anna Rosling ◽  
...  
Keyword(s):  
Molecular Identification ◽  
Sequence Similarity ◽  
Mineral Soil ◽  
Molecular Techniques ◽  
Root Tip ◽  
Root Tips ◽  
Soil Horizons ◽  
Novel Approach ◽  
Total Dna ◽  
Identification Techniques

ABSTRACT Molecular identification techniques based on total DNA extraction provide a unique tool for identification of mycelium in soil. Using molecular identification techniques, the ectomycorrhizal (EM) fungal community under coniferous vegetation was analyzed. Soil samples were taken at different depths from four horizons of a podzol profile. A basidiomycete-specific primer pair (ITS1F-ITS4B) was used to amplify fungal internal transcribed spacer (ITS) sequences from total DNA extracts of the soil horizons. Amplified basidiomycete DNA was cloned and sequenced, and a selection of the obtained clones was analyzed phylogenetically. Based on sequence similarity, the fungal clone sequences were sorted into 25 different fungal groups, or operational taxonomic units (OTUs). Out of 25 basidiomycete OTUs, 7 OTUs showed high nucleotide homology (≥99%) with known EM fungal sequences and 16 were found exclusively in the mineral soil. The taxonomic positions of six OTUs remained unclear. OTU sequences were compared to sequences from morphotyped EM root tips collected from the same sites. Of the 25 OTUs, 10 OTUs had ≥98% sequence similarity with these EM root tip sequences. The present study demonstrates the use of molecular techniques to identify EM hyphae in various soil types. This approach differs from the conventional method of EM root tip identification and provides a novel approach to examine EM fungal communities in soil.

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