scholarly journals Influence of Substrates in the Development of Bean and in Pathogenicity of Rhizoctonia solani JG Kühn

Agronomy ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 707
Author(s):  
Sara Mayo-Prieto ◽  
Álvaro Rodríguez-González ◽  
Alicia Lorenzana ◽  
Santiago Gutiérrez ◽  
Pedro A. Casquero
Keyword(s):  
Rhizoctonia Solani ◽  
Root System ◽  
Disease Severity ◽  
Trichoderma Harzianum ◽  
Aerial Part ◽  
Biocontrol Agent ◽  
Dry Weight ◽  
Optimal Growth ◽  
Germination Percentage ◽  
Economic Losses

The number of plants produced in horticultural substrates has increased over the last decade. These substrates are to have some physicochemical and phytosanitary characteristics that allow for optimal growth. Rhizoctonia solani JG Kühn is one of the root and hypocotyl diseases that frequently develops in seedbeds causing severe economic losses worldwide. The aim of this work was to evaluate the substrates and additives used in bean plantlets and the R. solani disease severity. The use of vermiculite or peat did not affect bean germination percentage, but peat promoted the development of the aerial part and vermiculite improved the growth of the root system. R. solani reduced bean germination percentage and bean growth in both peat and vermiculite. The presence of additives (bentonite and/or cornmeal) in the substrates (vermiculite or peat) reduced bean germination and development, favouring the severity of R. solani. However, the addition of cornmeal improves bean dry weight of the aerial part. So, whenever it is necessary to add additives to the substrates to improve the installation and development of a biocontrol agent, such as Trichoderma harzianum, the mix of peat and cornmeal would improve the development of both bean and biocontrol agent.

scholarly journals Is it necessary to soak rice grains to prepare Rhizoctonia solani AG-4 inoculum?

2007 ◽  
Vol 32 (6) ◽  
pp. 501-503 ◽  
Author(s):  
Trazilbo J. Paula Júnior ◽  
Rogério F. Vieira ◽  
Waldir C. Jesus Junior ◽  
Bernhard Hau ◽  
Hudson Teixeira
Keyword(s):  
Rhizoctonia Solani ◽  
Common Bean ◽  
Plant Height ◽  
Disease Severity ◽  
Root Rot ◽  
Dry Weight ◽  
Rice Grains ◽  
Emergence Curve ◽  
Plant Emergence

A study was conducted to evaluate the effects on the development of root rot on common bean, cv. 'Dufrix' after treatment with four volumes of water (0, 30%, 60%, and 90%, v/w) added to rice grains previously immersed in water for 24 hours before autoclaving and colonization of grains by Rhizoctoniasolani AG-4. Colonized rice grains and non-infested rice grains were mixed in pots with sterilized soil and sand (2:1), where beans were sown. Based on results of area under plant emergence curve, plant height, plant dry weight, and disease severity, we conclude that inoculum is more effective in causing disease when no water is added to the rice grains before autoclaving.

Effect of propagule size on the in vitro production of polygalacturonase and cellulase by Rhizoctonia solani

1974 ◽  
Vol 20 (12) ◽  
pp. 1713-1721 ◽  
Author(s):  
N. Lisker ◽  
J. Katan ◽  
Y. Henis
Keyword(s):  
Rhizoctonia Solani ◽  
Hydrolytic Enzymes ◽  
Cellulase Activity ◽  
Dry Weight ◽  
Germination Percentage ◽  
In Vitro Production ◽  
Potato Dextrose Broth ◽  
Propagule Size ◽  
Bean Hypocotyl

The physiological behavior of large (250–500 microns (μ)) infective and small (50–150 μ) non-infective mycelial fragments (propagules) of Rhizoctonia solani was compared. Liquid Czapek's medium containing sodium polypectate (NaPP) as the sole carbon source was inoculated with equal amounts (on a dry weight basis) of each kind of propagule. At NaPP concentrations of 0.005%–0.25% large propagules produced more polygalacturonase (PG) after a shorter period of incubation than small ones, whereas no differences in PG activity were observed at 1% NaPP. Differences in PG activity between large and small propagules were also observed in a medium consisting of 1:50 dilution of potato extract, but not in richer media such as potato dextrose broth and bean hypocotyl medium. These differences did not depend on pH of the medium or dry weight of the mycelium. Germination percentage of the large propagules and length of their emerging hyphae were greater than those of the small ones in media containing 0.005%–0.25% NaPP. Extracellular cellulase activity in Czapek's medium containing 0.25% carboxymethyl cellulose was also higher and appeared earlier in large propagules as compared with small ones. Viscometric and colorimetric methods for detecting PG and cellulase activities produced similar results. It is suggested that the capacity of the large propagules to produce hydrolytic enzymes at low nutrient levels may be important for their parasitic activity.

scholarly journals 872 PB 226 ENHANCED ROOT AND SHOOT GROWTH OF CHRYSANTHEMUM CUTTINGS PROPAGATED IN MEDIA INOCULATED WITH TRICHODERMA HARZIANUM

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 558f-558
Author(s):  
Amy J. MacKenzie ◽  
Terri W. Starman ◽  
Mark T. Windham
Keyword(s):  
Trichoderma Harzianum ◽  
Shoot Growth ◽  
Biocontrol Agent ◽  
Dry Weight ◽  
Shoot Length ◽  
Fresh Weight ◽  
White Marble ◽  
Shoot Fresh Weight ◽  
Root And Shoot Growth ◽  
Kg Medium

Trichoderma harzianum is a well-documented biocontrol agent that has been shown to enhance rooting of chrysanthemum `White Marble'. The objective of this research was to determine if T. harzianum would enhance rooting of hard-to-root chrysanthemum cuttings. Two hard-to-root cultivars (`Dark Bronze Charm' and `Golden Bounty') and two easy-to-root cultivars (`Davis' and `White Marble') were propagated in a 1:1 peat-perlite medium amended with T. harzianum at a rate of 0, 5, or 25g/kg medium. Measurements were taken 7, 14, and 21 days after insertion of the cuttings into the medium. Interactions occurred between rate of amendment and day of measurement for some variables measured. However, overall there was increased root fresh and dry weight of all cultivars when T. harzionum rates were 5 or 25 g/kg medium. Increased root fresh and dry weight occurred on days 14 and 21 for most cultivars. Root fresh and dry weight increased with increasing rate of amendment on day 14 but there was no difference between the 5 and 25 g/kg rates on day 21. Shoot fresh weight was increased with 5 or 25 g/kg each measurement day for all cultivar except `White Marble' and shoot length was increased with 25g/kg for all cultivars.

Salinity Tolerance of Black Gram Cultivars During Germination and Early Seedling Growth

2018 ◽  
Vol 51 (3) ◽  
pp. 51-68 ◽  
Author(s):  
M.K. Hasan ◽  
M.S. Islam ◽  
M.R. Islam ◽  
H.N. Ismaan ◽  
A. El Sabagh
Keyword(s):  
Salt Stress ◽  
Salinity Tolerance ◽  
Seedling Growth ◽  
Negative Impact ◽  
Germination Rate ◽  
Dry Weight ◽  
Germination Percentage ◽  
Shoot Length ◽  
Sand Culture ◽  
Black Gram

Abstract A laboratory experiment regarding germination and seedling growth test was conducted with three black gram genotypes tested under three salinity levels (0, 75 and 150 mM), for 10 days, in sand culture within small plastic pot, to investigate the germination and seedling growth characteristics. Different germination traits of all black gram genotypes, like germination percentage (GP), germination rate (GR), coefficient of velocity of germination (CVG) greatly reduced, as well as mean germination time (MGT) increased with increasing salt stress. At high salt stress, BARI Mash-3 provided the highest GP reduction (28.58%), while the lowest was recorded (15.79% to control) in BARI Mash-1. Salinity have the negative impact on shoot and root lengths, fresh and dry weights. The highest (50.32% to control) and lowest reduction (36.39%) of shoot length were recorded in BARI Mash-2 and BARI Mash-1, respectively, under 150 mM NaCl saline conditions. There were significant reduction of root lengths, root fresh and dry weight, shoot length, shoot fresh and dry weight in all genotypes under saline condition. The genotypes were arranged as BARI Mash-1 > BARI Mash-3 > BARI Mash-2, with respect to salinity tolerance.

Effect of the endophytic plant growth promoting Enterobacter ludwigii EB4B on tomato growth

2020 ◽  
Vol 13 (2) ◽  
pp. 54-65 ◽  
Author(s):  
M.E.A. Bendaha ◽  
H.A. Belaouni
Keyword(s):  
Root Length ◽  
Biocontrol Agent ◽  
Growth Promotion ◽  
Dry Weight ◽  
Antagonistic Activity ◽  
Rrna Gene ◽  
Plant Growth Promoting ◽  
Enterobacter Ludwigii ◽  
Tomato Growth

SummaryThis study aims to develop a biocontrol agent against Fusarium oxysporum f.sp. radicis-lycopersici (FORL) in tomato. For this, a set of 23 bacterial endophytic isolates has been screened for their ability to inhibit in vitro the growth of FORL using the dual plate assay. Three isolates with the most sound antagonistic activity to FORL have been qualitatively screened for siderophore production, phosphates solubilization and indolic acetic acid (IAA) synthesis as growth promotion traits. Antagonistic values of the three candidates against FORL were respectively: 51.51 % (EB4B), 51.18 % (EB22K) and 41.40 % (EB2A). Based on 16S rRNA gene sequence analysis, the isolates EB4B and EB22K were closely related to Enterobacter ludwigii EN-119, while the strain EB2A has been assigned to Leclercia adecarboxylata NBRC 102595. The promotion of tomato growth has been assessed in vitro using the strains EB2A, EB4B and EB22K in presence of the phytopathogen FORL. The treatments with the selected isolates increased significantly the root length and dry weight. Best results were observed in isolate EB4B in terms of growth promotion in the absence of FORL, improving 326.60 % of the root length and 142.70 % of plant dry weight if compared with untreated controls. In the presence of FORL, the strain EB4B improved both root length (180.81 %) and plant dry weight (202.15 %). These results encourage further characterization of the observed beneficial effect of Enterobacter sp. EB4B for a possible use as biofertilizer and biocontrol agent against FORL.

scholarly journals GERMINATION AND VIGOUR IN SEEDS OF THE COWPEA IN RESPONSE TO SALT AND HEAT STRESS

2019 ◽  
Vol 32 (1) ◽  
pp. 143-151 ◽  
Author(s):  
Luma Rayane de Lima Nunes ◽  
Paloma Rayane Pinheiro ◽  
Charles Lobo Pinheiro ◽  
Kelly Andressa Peres Lima ◽  
Alek Sandro Dutra
Keyword(s):  
Salt Stress ◽  
Heat Stress ◽  
High Temperature ◽  
Low Temperature ◽  
Vigna Unguiculata ◽  
Salt Concentration ◽  
Dry Weight ◽  
Germination Percentage ◽  
Different Types ◽  
Different Temperatures

ABSTRACT Salinity is prejudicial to plant development, causing different types of damage to species, or even between genotypes of the same species, with the effects being aggravated when combined with other types of stress, such as heat stress. The aim of this study was to evaluate the tolerance of cowpea genotypes (Vigna unguiculata L. Walp.) to salt stress at different temperatures. Seeds of the Pujante, Epace 10 and Marataoã genotypes were placed on paper rolls (Germitest®) moistened with different salt concentrations of 0.0 (control), 1.5, 3.0, 4.5 and 6.0 dS m-1, and placed in a germination chamber (BOD) at temperatures of 20, 25, 30 and 35°C. The experiment was conducted in a completely randomised design, in a 3 × 4 × 5 scheme of subdivided plots, with four replications per treatment. The variables under analysis were germination percentage, first germination count, shoot and root length, and total seedling dry weight. At temperatures of 30 and 35°C, increases in the salt concentration were more damaging to germination in the Epace 10 and Pujante genotypes, while for the Marataoã genotype, damage occurred at the temperature of 20°C. At 25°C, germination and vigour in the genotypes were higher, with the Pujante genotype proving to be more tolerant to salt stress, whereas Epace 10 and Marataoã were more tolerant to high temperatures. Germination in the cowpea genotypes was more sensitive to salt stress when subjected to heat stress caused by the low temperature of 20°C or high temperature of 35°C.

Mineral nutrition, dinitrogen fixation, and growth of Alnuscrispa and Alnusglutinosa

1985 ◽  
Vol 15 (5) ◽  
pp. 855-861 ◽  
Author(s):  
G. Prégent ◽  
C. Camiré
Keyword(s):  
Mineral Nutrition ◽  
Dry Weight ◽  
Optimal Growth ◽  
Maximum Growth ◽  
Dinitrogen Fixation ◽  
Weight Basis ◽  
Critical Levels ◽  
N Status

Invitro cultures of Alnuscrispa (Ait.) Pursh and Alnusglutinosa (L.) Gaertn. were used to estimate critical foliage levels of selected nutrients for optimal growth and dinitrogen (N2) fixation. For A. crispa to obtain 90% of maximum growth and N2 fixation, foliar levels of 0.12% P, 0.13% Mg, <0.31% K, and <0.04% Ca on a dry weight basis were needed. For A. glutinosa, the critical levels were 0.138% P, 0.10% Mg, 0.29% Ca, and ~0.20% K. From all the deficiencies observed, P had the more pronounced effects on N status of both species.

scholarly journals Genome-wide association analysis unveils novel QTLs for seminal root system architecture traits in Ethiopian durum wheat

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Admas Alemu ◽  
Tileye Feyissa ◽  
Marco Maccaferri ◽  
Giuseppe Sciara ◽  
Roberto Tuberosa ◽  
...  
Keyword(s):  
Durum Wheat ◽  
Root System ◽  
System Architecture ◽  
Root Length ◽  
Dry Weight ◽  
Root System Architecture ◽  
High Density ◽  
Soil Conditions ◽  
Root Dry Weight ◽  
Seminal Roots

Abstract Background Genetic improvement of root system architecture is essential to improve water and nutrient use efficiency of crops or to boost their productivity under stress or non-optimal soil conditions. One hundred ninety-two Ethiopian durum wheat accessions comprising 167 historical landraces and 25 modern cultivars were assembled for GWAS analysis to identify QTLs for root system architecture (RSA) traits and genotyped with a high-density 90 K wheat SNP array by Illumina. Results Using a non-roll, paper-based root phenotyping platform, a total of 2880 seedlings and 14,947 seminal roots were measured at the three-leaf stage to collect data for total root length (TRL), total root number (TRN), root growth angle (RGA), average root length (ARL), bulk root dry weight (RDW), individual root dry weight (IRW), bulk shoot dry weight (SDW), presence of six seminal roots per seedling (RT6) and root shoot ratio (RSR). Analysis of variance revealed highly significant differences between accessions for all RSA traits. Four major (− log10P ≥ 4) and 34 nominal (− log10P ≥ 3) QTLs were identified and grouped in 16 RSA QTL clusters across chromosomes. A higher number of significant RSA QTL were identified on chromosome 4B particularly for root vigor traits (root length, number and/or weight). Conclusions After projecting the identified QTLs on to a high-density tetraploid consensus map along with previously reported RSA QTL in both durum and bread wheat, fourteen nominal QTLs were found to be novel and could potentially be used to tailor RSA in elite lines. The major RGA QTLs on chromosome 6AL detected in the current study and reported in previous studies is a good candidate for cloning the causative underlining sequence and identifying the beneficial haplotypes able to positively affect yield under water- or nutrient-limited conditions.

scholarly journals Assessing the storage potential of Australian rainforest seeds: a decision-making key to aid rapid conservation

2021 ◽  
Author(s):  
K. D. Sommerville ◽  
G. Errington ◽  
Z-J. Newby ◽  
G. S. Liyanage ◽  
C. A. Offord
Keyword(s):  
Decision Making ◽  
Logistic Regression ◽  
Dry Weight ◽  
Germination Percentage ◽  
Fleshy Fruit ◽  
Seed Moisture Content ◽  
Fresh Seed ◽  
Desiccation Sensitivity ◽  
Seed Moisture ◽  
Seed Characteristics

AbstractSeed banking of rainforest species is hindered by lack of knowledge as to which species are tolerant of desiccation and freezing. We assessed 313 Australian rainforest species for seed banking suitability by comparing the germination percentage of fresh seeds to seeds dried at 15% RH and seeds stored at −20 °C after drying. We then compared desiccation responses to environmental, habit, fruit and seed characteristics to identify the most useful predictors of desiccation sensitivity. Of 162 species with ≥ 50% initial germination, 22% were sensitive to desiccation, 64% were tolerant and 10% were partially tolerant; the responses of 4% were uncertain. Of 107 desiccation tolerant species tested for response to freezing, 24% were freezing sensitive or short-lived in storage at −20 °C. Median values for fresh seed moisture content (SMC), oven dry weight (DW) and the likelihood of desiccation sensitivity (PD-S) were significantly greater for desiccation sensitive than desiccation tolerant seeds. Ninety-four to 97% of seeds with SMC < 29%, DW < 20 mg or PD-S < 0.01 were desiccation tolerant. Ordinal logistic regression of desiccation response against environmental, habit, fruit and seed characteristics indicated that the likelihood of desiccation sensitivity was significantly increased by a tree habit, fleshy fruit, increasing fresh SMC and increasing PD-S. The responses observed in this study were combined with earlier studies to develop a simple decision key to aid prediction of desiccation responses in untested rainforest species.

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