Management Of Root Rot Disease Research Articles

Ganoderma lucidum: Insights on host range, diagnosis, and management strategies.

Forest ecosystems play an important role in upholding life on our planet. However, the onslaught of fungal pathogens like Ganoderma lucidum, poses a threat by decimating numerous tree species. G. lucidum identified as a root pathogen, causing root rot in numerous tree species of horticulture and forestry importance. The fungus initiates infection through basidiospores, which germinate and penetrate within roots and start to degrade lignocellulosic components of plant cells. Early-stage detection of G. lucidum, is challenging, while in advance stages, the wood undergoes softening and a loss of tensile strength, rendering the disease incurable. Hence, effective management of G. lucidum necessitates a pivotal role of disease diagnostic techniques, which are currently underutilized or inadequately accessible. Subsequent implementation of suitable control measures becomes imperative to thwart disease occurrence and mitigate its impact in early stages, thus preserving the vitality of forest ecosystems. This study provides comprehensive overview of G. lucidum, covering taxonomy, pathogenicity, disease cycle, diagnosis and effective control measures, which will be helpful in formulating effective diagnostic techniques for early management of root rot disease.

Glucanase Gene of Trichoderma; New Strategy for the Management of Root Rot Disease in Chili

Glucanase Gene of Trichoderma; New Strategy for the Management of Root Rot Disease in Chili

Characterization of endophytic yeast and its suppressive effect on root rotting fungi of tomato under neem cake soil amendment

BackgroundThe exposure of crops to a variety of fungal and bacterial pathogens leads to huge economic losses. Different strategies are being adapted to control these diseases among which the application of chemicals fungicide is common. However, these chemicals are posing a serious threat to the environment. For biological management of root rot disease of tomato and better fruit quality, studies were conducted on the possible use of endophytic yeast as a biocontrol agent.ResultsEndophytic yeasts were isolated from healthy plants and identified. Identification of selected isolates was confirmed on the basis of 18S rDNA gene sequencing. They were evaluated for suppressive effect on root rotting fungi in vitro and also in vivo on tomato plants, used alone or under neem cake soil amendment. Seventy-six isolates of yeasts were evaluated against root rotting fungi Fusarium oxysporum, F. solani, Rhizoctonia solani and Macrophomina phaseolina using dual culture plate assay. Seventy-five isolates were found to suppress radial growth of F. oxysporum, F. solani and M. phaseolina by producing zones of inhibition or lysing the fungal hyphae. However, none of the isolates was found to inhibit R. solani in vitro. Most of the isolates also caused nematicidal activity at varying degree against Meloidogyne javanica. All test isolates produced indole acetic acid in vitro and solubilized phosphorus. In pots and field plot experiments, test isolates of yeasts were able to suppress root rotting fungi on tomato in natural soil and soil amended with neem cake with enhancement of growth of tomato plants. Yeasts were also found to ameliorate the plant resistance through enhancing polyphenolic contents, salicylic acid and antioxidant activity.ConclusionsEndophytic yeasts were found effective against root rot disease of tomato and could be used as a potential biocontrol agent for the management of soil-borne diseases of tomatoes.

Field evaluation of Rot-fix for management of root rot disease of mulberry (Morus sp.)

Mulberry is cultivated throughout India as a host plant of silkworm (Bombyx mori L.) reared for commercial production of silk. The quality of silk produced depends largely on the quality of leaf fed to silkworm. Various mulberry diseases limit quality and quantity of silk production affecting the economic return to the farmers. Among these, root rot caused by a group of fungi is a severe threat for mulberry leaf production, especially in southern states of India due to large scale mortality and enormous crop loss. Though many fungi are isolated from the infected root, Fusarium solani is the one frequently found associated with the disease. Chemical control with fungicides is not advisable due the environmental concern and toxicity to the soil and silkworm. Thus, recently a broad spectrum environment friendly formulation viz., Rotfix has been developed by the Central Sericultural Research & Training Institute, Mysore and recommended after limited on-farm and field trials. However its efficiency has not been evaluated at the farmers’ level in large scale. The present study has been conducted to evaluate the effect of Rot-fix in large scale in four southern states of India. The Rot-fix has been applied to the infected plants and their recovery has been studied. There was a high recovery (86.76-91.96%) of the infected plants after application of Rot-fix. Though the leaf yield was significantly (P<0.01) lower (2.48%) in the recovered plants in first crop, by the second crop the plants were recovered completely and started giving yield the statistically on par with untreated healthy plants. The study therefore recommends the use of Rot-fix in large scale for control of root rot disease of mulberry.

Impact of chitosan seed treatment of fenugreek for management of root rot disease caused by Fusarium solani under in vitro and in vivo conditions.

The use of chitosan as an alternative for fungicides has received more attention worldwide. Hence, this study aimed to evaluate in vitro and in vivo antifungal activity of chitosan against Fusarium solani causing root rot in fenugreek. Chitosan treatments ranged from 0.1 to 2gL-1 were tested against F. solani on to potato dextrose agar and in potato dextrose broth. The results revealed that increase in concentrations of chitosan significantly reduced growth, dried biomass, sporulation and spore germination of F. solani. The hyphal swellings and distortion of F. solani mycelia were induced by chitosan. Fenugreek seeds treated with chitosan at 2 gL-1 and 0.5 gL-1 showed reduced F. solani infection and increased seed germination, respectively. In pot and field studies, fenugreek seeds treated with chitosan at 2.0 gL-1 greatly reduced root rot disease severity and also enhanced yield parameters. The activity of defence enzymes, such as chitinase, β-1, 3-glucanase and total phenol were increased in chitosan treated in fenugreek plants. This increased activity offered protection to fenugreek plants against F. solani to a greater extent. The results showed that chitosan could be used as inducer of defense response and has the potential of controlling fenugreek root rot disease.

Endophytic fungi associated with soybean plants and their antagonistic activity against Rhizoctonia solani

BackgroundFungal endophytes produce many secondary metabolites that can reduce root rot diseases. Soybean is a particularly important crop worldwide. Endophytic fungi can be isolated, identified, and incorporated into sustainable agriculture for the biological control of many diseases.ResultsThe aim of this study was to isolate some endophytic fungi for controlling the most important diseases of soybean plants and to study the mechanisms underlying this biocontrol regarding the suppression of pathogens. Ten endophytic fungi were isolated from soybean plants. Among them, the 3 fungi isolates that exhibited a high percentage of antagonistic activity against Rhizoctonia solani, the causal pathogen of root rot disease of soybean plants, were identified as Trichoderma longibrachiatum S12, T. asperellum S11, and T. atroviride PHYTAT7. The 3 fungi isolates had the ability to produce pectinase and chitinase and to solubilize phosphors. Moreover, they produced siderophores and indole acetic acid (IAA), which have a strong effect on the growth of the plants. The 3 isolates reduced disease severity by 64, 60, and 55%, respectively than the infected control.ConclusionThe results suggest that certain endophytic fungi associated with soybean plants have potential for the management of root rot diseases in soybean. Moreover, these isolates can be considered as having a growth-promoting effect in soybean plants.

Bio management of root rot in Coleus forskohlii caused by Macrophomina phaseolina

Coleus forskohlii is an important medicinal plant native to India, which contains forskolin as an active ingredient in their roots. The crop has a great potential in future due to the expected increase in demand for forskolin which is widely used in glaucoma, cardiac problems, eczema, asthma, and hypertension and in the treatment of cancers. However, the crop has not become very popular among farmers because of its susceptibility to many diseases of which root- rot/wilt is the most important, causing serious losses to crop and affecting the tuber yield. Root rot/wilt is the major disease of C. forskohlii causing heavy losses (>50%) in south India. Biological control of the root rot diseases would be the only sustainable and potential control strategy to combat with the disease. Hence, the present study was conducted to find out effective bio agents for the management of root rot disease in coleus. The results revealed that basal soil application of Bacillus subtilis (Bbv 57) @ 2.5 kg/ha+ dipping root cuttings in 0.2% (Bbv 57) + soil application of Bbv 57) @ 2.5 kg/ha at 90 days after planting followed by treatment T1 with basal soil application of (SA) of B. subtilis (Bs1) @ 2.5 kg/ha + dipping cuttings in 0.2% B. subtilis (Bs1) + soil application of B. subtilis (Bs1) @ 2.5kg/ha was significantly superior in reducing the root rot incidence and in increasing the tuber root yield.

Molecular phylogeny, identification and pathogenicity of Rhizopus oryzae associated with root rot of mulberry in India.

Root rot caused by a group of fungi is a serious disease in mulberry. This study aims to identify and characterize Rhizopus oryzae and other fungal species associated with root rot of mulberry in India. Rotted root samples were collected from the mulberry gardens from four states of Southern India. The majority of the isolates identified were R. oryzae, and others were saprophytic fungi, less abundant to occasional. Two methods of inoculations were tested to confirm the pathogenicity of the selected isolates and R. oryzae was found to be pathogenic on susceptible mulberry genotypes RC2 and SRDC-1. Multi gene phylogenetic analyses using the internal transcribed spacer region (ITS), actin (ACT) and translation elongation factor 1-α (TEF), identified the isolates as R. oryzae. Additionally, Ovatospora brasiliensis, Amesia nigricolor, Gongronella butleri, Myrmecridium schulzeri, Scedosporium boydii, Graphium euwallacea, Clonostachys rosea andTalaromyces spp. were also identified. This study revealed the existence of eleven species of fungi including the first report of R. oryzae and the occurrence of weak pathogens or saprophytes that are associated with the root rot of mulberry in India. This is the first report of R. oryzae causing Rhizopus rot of mulberry in India. Moreover, the occurrence of saprophytes associated with root rot of mulberry was identified. Further studies should focus more on the ability of these species to generate secondary metabolites and extracellular lytic enzymes as they are beneficial for the management of root rot disease.

Evaluation of bioagents and chemicals for the management of root rot disease of bell pepper

Bell pepper (Capsicum annuum L. var. grossum Sendt.) a member of Solanaceae family, commonly known as “Sweet pepper ” or “Capsicum ” or “Shimla mirch ” has attained a status of high value crop among vegetables in India because of its delicacy and pleasant flavor besides being rich in fatty acids, flavanoids, volatile oil and carotene. Out of total six bioagent tested under in vitro condition, Trichoderma harzianum (SMA-5) and Trichoderma sp. (AF2) were observed as potential bioagents which inhibited the mycelial growth upto 84.7 per cent. Studies on different methods of application of bioagent revealed that drenching was effective in controlling disease (61.1%). In vitro evaluation of fungicides revealed that out of seven fungicides tested, Ridomil MZ and Moximate @ 100 μg/ml were highly fungitoxic as compare to other fungicides. Under pot experiments, Ridomil MZ and Moximate @ 0.25 per cent were found highly effective in managing root rot disease upto 64.7 and 59.0 per cent, respectively. Integrated application of Trichoderma sp. (PF2) with Ridomil MZ (1.75g/l) was found most effective in the management of Phytophthora root rot of bell pepper under polyhouse conditions.

Integrated strategies for the management of root rot disease of medicinal coleus (Coleus forskohlii Briq.) incited by Macrophomina phaseolina (Tassi.) Goid

Medicinal coleus (Coleus forskohlii) is a member of mint family Lamiaceae. The crop is affected by many diseases. Among them, the most challenging disease is dry root rot which is caused by Macrophomina phaseolina. The growing use of chemical fertilizers has been witnessing the grave consequence of global economic imbalance as well as environmental pollution. In this context of increased awareness, biocontrol agents and organic amendments can play a significant role in the future agro-economic scenario, as a partial substitute to chemical fertilizers. A survey was conducted in different coleus growing areas of Tamil Nadu and the pathogen associated with root rot infected plants was isolated and identified as M. phaseolina (Tassi.) Goid. Among the different native fungal and bacterial antagonists evaluated, Trichoderma viride (Tv-Ve1), Pseudomonas fluorescens (Pf-K3), Bacillus subtilis (Bs-K3) effectively inhibited the mycelial growth of M. phaseolina under in vitro conditions. Among the different oil cake extracts tested, neem cake (10%) and mahua cake (10%) effectively reduced the mycelial growth of M. phaseolina. The effective antagonists screened under in vitro conditions were further tested in pot culture experiments during the year 2014-15. The results of the pot culture experiment showed that soil application of T. viride (Tv-Ve1) at 5 g pot(-1) recorded the minimum disease incidence followed by T. viride (Tv-Si7) at 5 g pot(-1). The most effective antagonist and oil cake extracts screened both in laboratory and pot culture experiment, were further tested against the root rot disease under artificially inoculated condition. The results revealed that soil application of T. viride Tv-Ve1 (5 g pot(-1)) plus neem cake (20 g pot(-1)) recorded the lowest disease incidence (5.09%) which indicated 93.53% disease reduction over control. It can be concluded from the studies that biocontrol agents and organic amendments have potential to inhibit M. phaseolina when supplied as an organic amendment, thereby, supporting sustainable agriculture.

Integrated disease management of root rot (Macrophomina phaseolina) in Gloriosa superba

Root rot disease caused by Macrophomina phaseolina is a destructive disease in Gloriosa superba. The effect of organic amendments, fungicides and biocontrol agents in the management of root rot disease of G. superba was evaluated under field conditions. From the results, it was found that the combination treatment of soil application of Trichoderma viride (2.5 kg ha(-1)) along with mahua cake (150 kg ha(-1)), dipping the tubers in Pseudomonas fluorescens 0.2% followed by spraying tebuconazole + trifloxystrobin 0.1% twice on 30 and 60 days after planting was effective in managing the root rot disease and increasing the seed yield. The plant growth and yield parameters viz., plant height, number of flowers plant(-1), number of pods plant(-1) and number of seeds pod(-1) were the maximum in the combination treatment of soil application of T. viride (2.5 kg ha(-1)) along with mahua cake (150 kg ha(-1)), dipping the tubers in P. fluorescens 0.2% followed by spraying tebuconazole + trifloxystrobin 0.1% twice on 30 and 60 days after planting.

Management of root rot disease in French beans (Phaseolus vulgaris) by using microbial consortium

Management of root rot disease in French beans (Phaseolus vulgaris) by using microbial consortium

Management of root rot diseases of eight wheat varieties using resistance and biological control agents techniques

Management of root rot diseases of eight wheat varieties using resistance and biological control agents techniques

Evaluation of the biocontrol efficacy of a Serratia marcescens strain indigenous to tea rhizosphere for the management of root rot disease in tea.

The aim of the present study is to evaluate plant growth promoting and biocontrol efficacy of a Serratia marcescens strain ETR17 isolated from tea rhizosphere for the effective management of root rot disease in tea. Isolated bacterial culture ETR17 showed significant level of in vitro antagonism against nine different foliar and root pathogens of tea. The phenotypic and molecular characterization of ETR17 revealed the identity of the bacterium as Serratia marcescens. The bacterium was found to produce several hydrolytic enzymes like chitinase, protease, lipase, cellulase and plant growth promoting metabolites like IAA and siderophore. Scanning electron microscopic studies on the interaction zone between pathogen and antagonistic bacterial isolate revealed severe deformities in the fungal mycelia. Spectral analyses (LC-ESI-MS, UV-VIS spectrophotometry and HPLC) and TLC indicated the presence of the antibiotics pyrrolnitrin and prodigiosin in the extracellular bacterial culture extracts. Biofilm formation by ETR17 on polystyrene surface was also observed. In vivo application of talc-based formulations prepared with the isolate ETR17 in tea plantlets under green house conditions revealed effective reduction of root-rot disease as well as plant growth promotion to a considerable extent. Viability studies with the ETR17 talc formulation showed the survivability of the isolate up to six months at room temperature. The sustenance of ETR17 (concentration of 8-9x108 cfu g-1) in the soil after the application of talc formulation was recorded by ELISA. Safety studies revealed that ETR17 did not produce hemolysin as observed in pathogenic Serratia strains. The biocontrol strain reported in this study can be used for field application in order to minimize the use of chemical fungicides for disease control in tea gardens.

Management of Root Rot Diseases of Cool Season Food Legumes Crops in Ethiopia

Particularly in Ethiopia legumes grown in 2014/15 covered 12.41% (1,558,442.04 hectares) of the grain crop area and 9.88% (about 26,718,430.40 quintals) of the grain production was drawn from the same crops. Legumes, which occupy approximately 13 percent of cultivated land and account for approximately 10 percent of the agricultural value addition, are critical to smallholder livelihoods in Ethiopia. The major constraints to the production of these crops are diseases, insect pest attack, poor agronomic practices and lack of improved cultivars and crop protection technologies. Root rot diseases are a major limiting factor in legume production. The diseases depress seedling germination and cause post emergence damping off, resulting in poor crop stand and low yields. Several root rot casing pathogen such as Rhizoctonia bataticola, Rhizoctonia solani and Fusarium solani on chickpea, Rhizoctonia bataticola and Rhizoctonia solani on lentil and Rhizoctonia bataticola, Rhizoctonia solani and Fusarium solani on faba bean have been reported in Ethiopia. They can cause yield loss up to 45% and 50% in faba bean and chickpea if properly not manage. Based on this information review was made to review some available root rot management methods of legume crops and to make some suggestions on the methods which are not practice yet. Several chemicals, cultural practice and bio-gent used to control this disease. Among bio-agent mostly used to control this disease are Trichoderma viride and Bacillus megaterium take a great share. In the future particularly in our country full exploitation of the potential of biological control of this disease has to be done. In general techniques which are based on the molecular techniques like marker assisted selection to deploy resistance has to be applied in the processes of creating resistant variety development.

Integrated Management of Root Rot Disease of Papaya (Carica papaya L.) caused by Fusarium solani

Present study the most effective fungicides, plant extract, organic cake and bio-agent were evaluated in different combinations under field conditions for the management of papaya root rot disease. It was observed that there was 81.5% disease incidence in control while the lowest disease incidence (29.60%) was recorded in treatment (T ) (Comprising disease free seedling + mustard 13 cake (10%)+ wild garlic (10%) + dipping of seedlings in thiophanate methyl (0.1%) 30 min.+ soil drenching with thiophanate methyl (0.1%) solution three times (1st at time of transplanting, second at 3rd MAT and third at 5th month after transplanting)+ Soil application of Trichoderma viride @ 50g/plant three times (i.e. 1st at time of transplanting, second at 3rd MAT and third at 5th MAT)+ soil application of Pseudomonas florescence @ 50g/plant three times (i.e. 1st at time of transplanting, second at 3rd MAT and third at 5th MAT). This was followed by treatment T (37.0%), T (40.7%) and T 6 9 5 (44.4%). The effect of different treatments on yield was also studied and the highest fruit yield (1064.67 kg/plot) was obtained from the treatment T followed by treatment T (848.67 kg/plot) and 13 9 T (810.00 kg/plot) over the control T (209.00 kg/plot).

Evaluation of Penicillium sp. Eu0013 for management of Root rot disease of Okra

Evaluation of Penicillium sp. Eu0013 for management of Root rot disease of Okra

Efficacy of Water Extracts of Some Mangrove Plants for Eco-friendly Management of Root Rot Disease of Groundnut

Root rot of groundnut caused by Macrophomina phaseolina causes significant losses in groundnut growing areas of Tamil Nadu. Hence, the present study was conducted to assess the prevalence and incidence of dry root rot of groundnut in different district of Tamil Nadu, India during 2013-14, assess the cultural characters and pathogenic variability among the isolates of M. phaseolina and to test the antifungal activity of water extracts from mangrove plants against pathogen. The results revealed that the maximum root rot incidence was observed (30.33%) in Sivapuri village of (I3) Cuddalore district. The disease incidence was more in, VRI2 variety and incidence was found to be more in sandy loam soils. Regarding the cultural characteristics revealed that the isolates I2 and I3 significantly recorded the maximum (90 mm) mycelial growth of M. phaseolina and the isolate I3 was found to be more virulent when compared to other isolates tested. Water extracts of nine mangrove plant species were screened against the root rot pathogen, M. phaseolina. Of these, Salicornia brachiata (21.33 mm), Rhizophora apiculata (23.00 mm) and Suaeda maritima (26.33 mm) were found to be highly effective against the test pathogen

English

  Among seventy isolates, antagonistic twenty one representing biovars of Pseudomonas fluorescens (biovars I, II, III, and V) were collected from the rhizosphere of okra, chilli, ground nut, brinjal, cabbage and tomato from different agro-ecological regions of West Bengal and were subjected to evaluate for their antifungal activity under in vitro condition against Rhizoctonia solani, the most important soil-borne plant pathogen two isolates, PF-8 and PF-7 effectively inhibited the mycelial growth of Rhizoctonia solani (72.05 and 68.25%, respectively) in dual culture method. The vigour index of okra was also recorded maximum for the isolate PF-8 (2415.7) followed by PF-7 (2063.25). Mechanisms of fungal inhibition were elucidated by tracing secondary-metabolite production of the rhizobacterial isolates. Most of the isolates expressed a specific mechanism of antagonism, as represented by production of pigments, Siderophores, cyanide (HCN), Indole Acetic acid (IAA) and Salicylic Acid (SA) production, and Phosphate solubilization. Rhizobacterial isolate PF-8 was found to be effective as seed and soil treatment for management of root rot disease of okra. The antagonistic nature of fluorescent pseudomonads against fungal pathogens can be assigned to design a potential candidate for development of agriculture sector to be used in biological control of soil borne plant pathogens.   Key words: Fluroscent pseudomonads, secondary metabolites, Rhizoctonia solani, okra root rot.

Management of root rot disease of groundnut (Arachis hypogeae L.) by plant extracts

A field experiment was conducted during 2009 to 2010 crop season in district Chakwal to evaluate the efficiency of aqueous extracts of five plant species, namely Allium cepa L. (onion), Allium sativum L. (garlic), Boerhaavia diffusa auct. Plur., Calotropis procera (Aiton) W.T. Aiton., Cannabis sativa L., and two fungicide antracol and ridomil and both fungicides in mixture form, to manage the root rot disease of groundnut (Arachis hypogeae L.) caused by a fungal pathogen Fusarium solani (Mart) Sacc. Fusarium inoculation showed 98% disease incidence with 22% mortality. Recommended dose of the chemical fungicides antracol and ridomil significantly reduced the disease incidence to 17 and 18%, respectively and mortality to 10% each separately. Fungicides in mixture form reduced the disease and mortality to 10 and 7%, respectively. Plant extract treatments exhibited variable effects on the incidence of the disease and mortality of plants. In general, all the test plant extracts managed the root rot disease to varying degrees. Aqueous bulb extracts of A. sativum andA. cepa and the leaf extract of C. procera showed better disease management potential than that of the recommended doses of antracol and ridomil. Fusarium inoculation significantly declined plant growth. In general, antracol and ridomil, as well as aqueous extracts, enhanced plant growth to variable degrees as compared to the Fusarium control. Key words: Root rot, Fusarium solani, groundnut, plant extracts.