Application of selected biological control agents in conjunction with tolclofos-methyl for the control of damping-off caused by Rhizoctonia solani

Evaluation of five inner carriers and Bacillus subtilis formulation to control banded leaf and sheath blight (Rhizoctonia solani Kuhn). One alternative control method against plant pathogens is the use of antagonistic microorganisms, such as Bacillus subtilis. The use of the antagonistic bacteria on corn especially in Indonesia is still lack. The objective of this research was to evaluate some inner carrier and to make formulated antagonistic B. subtilis to be used as biological control agents on corn diseases. This research consists of laboratory and greenhouse activities. The laboratory activities consist of B. subtilis biomass production, formulation of B. subtilis, and evaluation of five types of inner carrier. In the greenhouse, testing the formulation B. subtilis with talc as an inner carrier, which is compared with the treatment solution of B. subtilis, nordox, metalaxyl fungicides. The data collected in this study were percentage of germination, damping off due to pathogen R. solani, plant height, plant fresh weight, and percentages of R. solani incidence on 14 DAP. The results showed that talc powder and corn flour were the best inner carrier to be used in sorage formulation of antagonistic Bacillus. Formulated Bacillus subtilis TM4 showed no negative affect on seed germination and able to suppress the development of R. solani in greenhouse.

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Application of plant extracts and Trichoderma harzianum for the management of tomato seedling damping-off caused by Rhizoctonia solani

South African Journal of Science ◽

10.17159/sajs.2020/7860 ◽

2020 ◽

Vol 116 (11/12) ◽

Author(s):

Mapula T.P. Hlokwe ◽

Mapotso Kena ◽

David N. Mamphiswana

Keyword(s):

Biological Control ◽

Rhizoctonia Solani ◽

Plant Extracts ◽

Trichoderma Harzianum ◽

Moringa Oleifera ◽

Plant Diseases ◽

Yield Reduction ◽

Biotic Factors ◽

Damping Off ◽

Tomato Seedling

Seedling production under smallholder farming systems can be negatively affected by both abiotic and biotic factors. Seedling damping-off caused by Rhizoctonia solani is one of the major biotic factors which causes significant yield reduction. Management is mainly based on the application of synthetic fungicides and cultural practices. However, both methods have limitations which result in their inefficiency. Several studies have reported on the use of plant extracts and biological control to manage plant diseases. The aim of this study was to formulate an effective and practical approach to manage tomato seedling dampingoff using extracts of Monsonia burkeana and Moringa oleifera and a biological control agent Trichoderma harzianum. The efficacy of both extracts was investigated under laboratory conditions to determine the most suppressive concentration to R. solani growth. Methanolic extracts from both plants significantly suppressed pathogen growth at different concentrations. M. burkeana significantly reduced R. solani growth at 8 g/mL (71%) relative to control whilst Moringa oleifera extract reduced pathogen growth by 60% at a concentration of 6 g/mL. The highest suppressive concentrations were further evaluated under greenhouse conditions to test their efficacy on seedling damping-off. In damping-off treatments, both plant extracts and T. harzianum also significantly reduced (p=0.5) pre- and post-emergence dampingoff incidence. M. burkeana recorded the highest suppression at 78%, followed by M. oleifera at 64%. Trichoderma harzianum reduced incidence of damping-off by 60% and this was higher than both plant extract treatments.

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Efficacy of Chemical and Biological Agents to Suppress Fusarium and Pythium Damping-Off of Container-Grown Douglas-fir Seedlings

Plant Health Progress ◽

10.1094/php-2008-0317-02-rs ◽

2008 ◽

Vol 9 (1) ◽

pp. 20 ◽

Cited By ~ 4

Author(s):

Robert G. Linderman ◽

E. Anne Davis ◽

Charles J. Masters

Keyword(s):

Biological Control ◽

Douglas Fir ◽

Biological Agents ◽

Biological Control Agents ◽

Damping Off ◽

Pythium Irregulare ◽

Plant Soil ◽

Container Nurseries ◽

Steam Pasteurization ◽

Conifer Seedling

Douglas-fir seedlings are susceptible to Fusarium or Pythium damping-off that currently is controlled by pre-plant soil fumigation in bareroot nurseries and steam pasteurization or chemical drenches of soilless media in container nurseries. However, because few chemical or biological agents are registered for use on conifer seedlings, we tested several on greenhouse-grown seedlings and found that over-seed applications of Cleary's 3336, Strike, Compass, Compass + Strike, Cygnus, Endura, Medallion, Medallion + Strike, Thiram, and Enzone effectively suppressed pre-emergence damping-off by Fusarium oxysporum, but only Cleary's 3336WP and Medallion + Strike also reduced post-emergence damping-off. Compass, Medallion, and Thiram reduced post-emergence damping-off, but not to a statistically significant level. Pre-emergence damping-off by Pythium irregulare was reduced only by Ranman, but post-emergence damping-off was reduced by Thiram, Hurricane, Ranman, and Subdue MAXX. Over-seed drenches of biological control agents Companion, Kodiak, Subtilex, Taegro, Primastop, SoilGard, Actinovate, Mycostop, RootShield, and Green-Releaf were ineffective in suppressing either Fusarium or Pythium diseases, and combining several agents with chemicals did not improve efficacy. These results provide data in support of registration of some of the effective chemicals, but no biological control agents, for the control of conifer seedling damping-off. Accepted for publication 14 January 2008. Published 17 March 2008.

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Control of damping-off and root rot diseases of Acacia tree using some biological control agents and plant extracts

Research on Crops ◽

10.31830/2348-7542.2020.027 ◽

2020 ◽

Vol 21 (1) ◽

Keyword(s):

Biological Control ◽

Plant Extracts ◽

Root Rot ◽

Biological Control Agents ◽

Damping Off ◽

Acacia Tree

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Mechanism of seedling protection induced by a hypovirulent isolate of Rhizoctonia solani

Canadian Journal of Botany ◽

10.1139/b89-270 ◽

1989 ◽

Vol 67 (7) ◽

pp. 2135-2141 ◽

Cited By ~ 23

Author(s):

B. Sneh ◽

M. Ichielevich-Auster ◽

Z. Plaut

Keyword(s):

Biological Control ◽

Cell Wall ◽

Plant Growth ◽

Rhizoctonia Solani ◽

Growth Response ◽

Damping Off ◽

Produce Cell ◽

Protected Plants ◽

Hypovirulent Strain ◽

Seedling Protection

Among several hypovirulent isolates of Rhizoctonia spp. tested, one isolate (No. 521) provided significantly higher protection (76–94%) to radish and cotton seedlings against infection by virulent isoltes of Rhizoctonia spp. and also induced a higher increased plant growth response than the others. The hypovirulent strain did not compete for root exudates. The protected plants were not induced to produce new polyphenols, melanins, more lignins, or phytoalexins. Also they did not produce inhibitors of pectinases or cellulases released by the pathogen, nor did they produce cell wall lytic-type enzymes, such as chitinase and β-(1,3) glucanase. Ca2+ content was significantly higher in seedlings colonized by the hypovirulent isolate. The hypovirulent isolate densely colonized the surface of roots and hypocotyls, and removal of its hyphae nullified the protection provided by this isolate. Key words: Rhizoctonia solani, damping-off, hypovirulent isolate, biological control.

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