Nandani Shukla - Academia.edu (original) (raw)

Papers by Nandani Shukla

The glasshouse and laboratory experiments were conducted to evaluate the enzymatic activity of th... more The glasshouse and laboratory experiments were conducted to evaluate the enzymatic activity of the antioxident enzymes viz; Phenylalanine ammonia lyase (PAL), Catalase (CAT) and Peroxidase (PO) against X. axonopodis pv. citri for different treatments at, Department of Plant Pathology, College of Agriculture, G.B.P.U.A. &T., Pantnagar. Experiment was laid out in Completely Randomized Design (CRD) in glass house comprising ten treatment combinations replicated thrice, where the pretreatment of citrus plants with Pant bioagent 2, Pant bioagent 3, L-methionine, GABA and Salicylic acid induced the levels of plant defense and thus induced disease resistance against X. axonopodispv.citri. These compounds can be used as effective alternative compounds to copper bactericides for the management of citrus canker.

International journal of Bio-resource and Stress Management, 2015

Annals of Applied Biology, 2014

Green house study was aimed to investigate the effect of seed biopriming with drought tolerant is... more Green house study was aimed to investigate the effect of seed biopriming with drought tolerant isolates of Trichoderma harzianum, viz. Th 56, 69, 75, 82 and 89 on growth of wheat under drought stress and to explore the mechanism underlying plant water stress resilience in response to Trichoderma inoculation. Measurements of relative water content, osmotic potential, osmotic adjustment, leaf gas exchange, chlorophyll fluorescence and membrane stability index were performed. In addition, analysis of the phenolics, proline, lipid peroxidation and measurements of phenylalanine ammonia-lyase activity were carried out. Seed biopriming enhanced drought tolerance of wheat as drought induced changes like stomatal conductance, net photosynthesis and chlorophyll fluorescence were delayed. Drought stress from 4 to 13 days of withholding water induced an increase in the concentration of stress induced metabolites in leaves, while Trichoderma colonisation caused decrease in proline, malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2), and an increase in total phenolics. A common factor that negatively affects plants under drought stress conditions is accumulation of toxic reactive oxygen species (ROS), and we tested the hypothesis that seed biopriming reduced damages resulting from accumulation of ROS in stressed plants. The enhanced redox state of colonised plants could be explained by higher L-phenylalanine ammonia-lyase (PAL) activity in leaves after 13 days of drought stress in Trichoderma treated plants. Similar activity was induced in untreated plants in response to drought stress but to a lower extent in comparison to treated plants. Our results support the hypothesis that seed biopriming in wheat with drought tolerant T. harzianum strains increased root vigour besides performing the process of osmoregulation. It ameliorates drought stress by inducing physiological protection in plants against oxidative damage, due to enhanced capacity to scavenge ROS and increased level of PAL, a mechanism that is expected to augment tolerance to abiotic stresses.

Journal of Functional And Environmental Botany, 2015

Biocontrol or Biological Control can be defined as the use of natural organisms or genetically mo... more Biocontrol or Biological Control can be defined as the use of natural organisms or genetically modified genes or gene products, to reduce the effects of undesirable organisms to favour organisms useful to human, such as crops, trees, animals and beneficial microorganisms. This strategy of control is ecologically clean and compatible with different models of agriculture: organic, biological and integrated pest/pathogen management (IPM) programmes. The main antagonist used in disease control in agriculture is the fungus Trichoderma, a low cost biocontrol agent that can establish it in different pathosystems, has moderate effects on soil balance and does not harm beneficial organism that contribute towards pathogen's control. This biocontrol agent has no harmful effects on humans, wildlife and other beneficial organisms. Trichoderma spp. is safe and effective biocontrol agents in both natural and controlled environments that does not accumulate in the food chain and to which resistance has not been described. Trichoderma strains used as biocontrol agents can act by colonising the soil and/or parts of the plant, occupying a physical space and avoiding the multiplication of the pathogens or producing cell wall degrading enzymes against the pathogens or producing antibiotics that can kill the pathogens or promoting the plant development and inducing the defensive mechanisms of the plant. Antifungal formulations based on Trichoderma strains and proteins require, as in the case of chemical fungicides, a costly and sound registration process previous to their commercialisation. For this reason, many of these biological products are being offered to the farmers under the category of fertilisers and other commercial products that are not tightly regulated, and, hence, they do not offer sufficient guarantee of quality and sanitary control. This fraud must be prosecuted since most of these wrongly registered formulations have not got a Trichoderma inoculums ’, shelf life or other properties stated on their label.

Plant and Soil, 2011

Salt stress is one of the major abiotic stresses limiting crop growth and productivity. This work... more Salt stress is one of the major abiotic stresses limiting crop growth and productivity. This work investigated the potential of five ST isolates of Trichoderma harzianum (Th-13, Th-14, Th-19, Th-33 and Th-50) applied through seed biopriming in reducing the detrimental effects of salinity stress on wheat (Triticum aestivum L.). Growth, physiological and biochemical parameters were studied to characterize salt tolerance. One factor was treatments (T1, T2, T3, T4, T5 and T6) and second factor was four levels of salt stress viz., 0, 2, 4 and 6 dsm −1. In germination test, most of the isolates (Th-14, Th-19 and Th-13) were effective in improving germination percentage and reducing RPG during salinity stress. Seedlings raised from ST Trichoderma isolates had significantly higher root and shoot lengths, CC and MSI than control at all stress levels. The treatments Th-14, Th-19 and Th-13 showed lower accumulation of MDA content whereas proline content and phenolics were higher in treated plants under both nonsaline and saline conditions. Highest MDA content was observed in control at salt stress level of 6 dSm −1. It is concluded that seed biopriming with different salinity tolerant isolates of Trichoderma reduced severity of the effects of salinity though the amelioration was better in Th-14 under present experimental material and conditions.

A total of 22 Trichoderma isolates TCMS 2, 4, 5, 14b, 15, 16, 24, 32, 34, 36, 60, 62, 65 and 93, ... more A total of 22 Trichoderma isolates TCMS 2, 4, 5, 14b, 15, 16, 24, 32, 34, 36, 60, 62, 65 and 93, Th 1,3, 13, 14, 19 and 32, SBIT 32 and 76) were evaluated for their compatibility with dual combinations of copper hydroxide and chitosan (ChoF: liquid formulation) under in vitro conditions to check their maximum tolerance limit. The Trichoderma isolates were screened at graded (250+250, 500+500, 1000+1000 and 2000+2000 ppm) combinations of copper hydroxide and chitosan. At dual combination (250 ppm each), all the tested Trichoderma isolates showed cent per cent growth and thus found highly compatible. Only six isolates viz., TCMS-36, TCMS-60, TCMS-62, TCMS-65, SBIT-32 and SBIT-76 found compatible with exhibiting hundred per cent growth at 500 ppm (each) combination of copper hydroxide and chitosan. At 1000 ppm (each) combination only six isolates were found partially tolerant and none of the isolates was found completely tolerant. Maximum growth was observed in SBIT32 and TCMS-14b (3.6...

Journal of Plant Pathology, 2012

A greenhouse experiment was conducted to examine the effect of seed biopriming with five salinity... more A greenhouse experiment was conducted to examine the effect of seed biopriming with five salinity tolerant isolates of Trichoderma harzianum on the response of rice (Oryza sativa L.) to different salt stress levels. One factor was different Trichoderma treatments (Th-13, Th- 14, Th-19, Th-33 and Th-50) and the second factor was four levels of salt stress viz., 0, 70, 150 and 240 mM NaCl. Growth, physiological and biochemical parameters were determined to characterize salt tolerance. Salt stress adversely affected the studied parameters. However, the data revealed that Trichoderma treatments alleviated the stress condition and significantly increased length and fresh weight of shoot and root, number of leaves, leaf area, photosynthetic rate, chlorophyll fluorescence, chlorophyll content and soil plant analysis development (SPAD) value in comparison to control at all stress levels. Trichoderma treatments also resulted in the alleviation of oxidative damage, as indicated by the decreas...

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service... more This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Morphological and molecular characterization of Eimeria haematodi, coccidian parasite (Apicomplexa:Eimeriidae) in a rainbow lorikeet (Trichoglossus haematodus

Present field experiment was conducted to compare the efficacy of different copper compounds viz.... more Present field experiment was conducted to compare the efficacy of different copper compounds viz.; CuOH (Technical grade), CuOH (Kocide) and Copper sulphate pentahydrate (CuSO4.5H2O) in combination with chitosan (Cs661) and Trichoderma asperellum (Tri) to find out the most effective copper source in the combination for late blight disease management in tomato. Among the three copper compounds, CuOH (TG) was found to be the most effective copper source in the combination. Minimum disease severity (2.33%) was recorded in plots treated with CuOH (TG)+Cs661(Ac)+Tri whereas maximum disease severity was recorded in control plot (40%) after 95 DAT. In terms of other attributes such as yield, reduction in disease progress (A and r value), the most effective treatment was CuOH (TG)+Cs661(Ac)+Tri, which was at par with standard fungicide mancozeb and significantly higher as compared to control. The preliminary results suggest that the combination variants having CuOH as copper source could be...

Annals of Plant Protection Sciences

Journal of Applied and Natural Science

In vitro efficacy of twenty five Trichoderma isolates (twenty were TCMS series viz., TCMS 2, 4, 5... more In vitro efficacy of twenty five Trichoderma isolates (twenty were TCMS series viz., TCMS 2, 4, 5, 12, 14a, 14b, 15, 16, 24, 32, 34, 36, 43, 60, 62, 64, 65, 72, 85 and 93, and five Th series; Th 1, 3, 14, 19 and 32) were ascertained for their antagonistic activity against few major plant pathogenic oomycetes namely, Phytophthora infestans, P. parasitica and Pythium aphenidermatum using dual culture technique. P. infestans was isolated from infected potato leaves and Pythium aphenidermatum from infected brinjal. P. parasitica culture was collected from Central Potato Research Institute (CPRI), Simla. The present study was conducted at Biological Control Laboratory, Department of Plant Pathology, G.B. Pant University of Agriculture and Technology, Pantnagar. All the 25 Trichodrma isolates were found significantly effective against the test pathogens. TCMS-36 and TCMS-72 were found highly effective against P. aphinidermatum with 59.57 per cent inhibition of radial growth of the fungus....

International Journal of Current Microbiology and Applied Sciences

Journal of Applied and Natural Science

Mycotoxins are toxic secondary metabolic products of various fungi, mainly belonging to the gener... more Mycotoxins are toxic secondary metabolic products of various fungi, mainly belonging to the genera Fusarium (Trichothecenes, Zearalenone), Aspergillus (Aflatoxin) and Penicillium (Ochratoxin) and can be found in almost 25% of the world’s agricultural commodities. These compounds are toxic to humans, animals and plants and therefore, efforts should be made to avoid mycotoxin contamination in food and feed. It has been estimated that at least 300 of these fungal metabolites are potentially toxic to animals and humans. In India 50% losses of agricultural commodities are due to postharvest losses. A number of physical and chemical approaches have already been taken to reduce the effect of mycotoxins, but due to certain limitations of physical and chemical strategies prompted search for other solutions to the mycotoxin hazards. Thus, there is an increasing public pressure for a safer and eco-friendly alternative to control these organisms. Consequently, a new approach is applied for mana...

International Journal of Current Microbiology and Applied Sciences

World Population Prospects, 2011). Pests (which include invertebrates, pathogens and weeds) are e... more World Population Prospects, 2011). Pests (which include invertebrates, pathogens and weeds) are estimated to cause between 27% and 42% losses in production for major crops around the world, but this would rise to a staggering 48-83% without crop protection (Oerke, 2006). Therefore, in order to meet the growing food demand, about 15-20 times increase in the use of synthetic pesticides will be required (Oerke, 2006) but the excessive

Plant Physiology and Biochemistry, 2012

Rice is one of the most important food crops drastically affected by drought in lowland rice ecos... more Rice is one of the most important food crops drastically affected by drought in lowland rice ecosystems. In the present study, the impact of drought tolerant isolates of endophytic fungus Trichoderma harzianum on rice response to drought was investigated. Out of 43 Trichoderma isolates studied, only five isolates viz., Th 56, Th 69, Th 75, Th 82 and Th 89 were selected to be drought tolerant as these were able to colonize well on cow dung at low moisture content of 10-20 percent, though two isolates, Th 56 and Th 75, grew even at 5 percent moisture content. Trichoderma-colonized rice seedlings were slower to wilt in response to drought. Colonization delayed drought induced changes like stomatal conductance, net photosynthesis and leaf greenness. Drought conditions varying from 3 to 9 days of withholding water led to an increase in the concentration of many stress induced metabolites in rice leaves and decrease of MSI, while Trichoderma colonization caused a decrease in proline, MDA and H₂O₂ contents, and increase in phenolics concentration and MSI. Among test isolates, Th 56 induced maximum drought tolerance as treated plants recorded only 20-40 percent wilting even at 9 DDS. With or without exposure to drought, colonization by Trichoderma promoted seedling growth, with Th 56 giving the most consistent effect. The primary direct effect of Trichoderma colonization was promotion of root growth, regardless of water status, which caused delay in the drought responses of rice plants.

Plant physiology and biochemistry : PPB / Société française de physiologie végétale, 2012

Rice is one of the most important food crops drastically affected by drought in lowland rice ecos... more Rice is one of the most important food crops drastically affected by drought in lowland rice ecosystems. In the present study, the impact of drought tolerant isolates of endophytic fungus Trichoderma harzianum on rice response to drought was investigated. Out of 43 Trichoderma isolates studied, only five isolates viz., Th 56, Th 69, Th 75, Th 82 and Th 89 were selected to be drought tolerant as these were able to colonize well on cow dung at low moisture content of 10-20 percent, though two isolates, Th 56 and Th 75, grew even at 5 percent moisture content. Trichoderma-colonized rice seedlings were slower to wilt in response to drought. Colonization delayed drought induced changes like stomatal conductance, net photosynthesis and leaf greenness. Drought conditions varying from 3 to 9 days of withholding water led to an increase in the concentration of many stress induced metabolites in rice leaves and decrease of MSI, while Trichoderma colonization caused a decrease in proline, MDA ...

The glasshouse and laboratory experiments were conducted to evaluate the enzymatic activity of th... more The glasshouse and laboratory experiments were conducted to evaluate the enzymatic activity of the antioxident enzymes viz; Phenylalanine ammonia lyase (PAL), Catalase (CAT) and Peroxidase (PO) against X. axonopodis pv. citri for different treatments at, Department of Plant Pathology, College of Agriculture, G.B.P.U.A. &T., Pantnagar. Experiment was laid out in Completely Randomized Design (CRD) in glass house comprising ten treatment combinations replicated thrice, where the pretreatment of citrus plants with Pant bioagent 2, Pant bioagent 3, L-methionine, GABA and Salicylic acid induced the levels of plant defense and thus induced disease resistance against X. axonopodispv.citri. These compounds can be used as effective alternative compounds to copper bactericides for the management of citrus canker.

International journal of Bio-resource and Stress Management, 2015

Annals of Applied Biology, 2014

Green house study was aimed to investigate the effect of seed biopriming with drought tolerant is... more Green house study was aimed to investigate the effect of seed biopriming with drought tolerant isolates of Trichoderma harzianum, viz. Th 56, 69, 75, 82 and 89 on growth of wheat under drought stress and to explore the mechanism underlying plant water stress resilience in response to Trichoderma inoculation. Measurements of relative water content, osmotic potential, osmotic adjustment, leaf gas exchange, chlorophyll fluorescence and membrane stability index were performed. In addition, analysis of the phenolics, proline, lipid peroxidation and measurements of phenylalanine ammonia-lyase activity were carried out. Seed biopriming enhanced drought tolerance of wheat as drought induced changes like stomatal conductance, net photosynthesis and chlorophyll fluorescence were delayed. Drought stress from 4 to 13 days of withholding water induced an increase in the concentration of stress induced metabolites in leaves, while Trichoderma colonisation caused decrease in proline, malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2), and an increase in total phenolics. A common factor that negatively affects plants under drought stress conditions is accumulation of toxic reactive oxygen species (ROS), and we tested the hypothesis that seed biopriming reduced damages resulting from accumulation of ROS in stressed plants. The enhanced redox state of colonised plants could be explained by higher L-phenylalanine ammonia-lyase (PAL) activity in leaves after 13 days of drought stress in Trichoderma treated plants. Similar activity was induced in untreated plants in response to drought stress but to a lower extent in comparison to treated plants. Our results support the hypothesis that seed biopriming in wheat with drought tolerant T. harzianum strains increased root vigour besides performing the process of osmoregulation. It ameliorates drought stress by inducing physiological protection in plants against oxidative damage, due to enhanced capacity to scavenge ROS and increased level of PAL, a mechanism that is expected to augment tolerance to abiotic stresses.

Journal of Functional And Environmental Botany, 2015

Biocontrol or Biological Control can be defined as the use of natural organisms or genetically mo... more Biocontrol or Biological Control can be defined as the use of natural organisms or genetically modified genes or gene products, to reduce the effects of undesirable organisms to favour organisms useful to human, such as crops, trees, animals and beneficial microorganisms. This strategy of control is ecologically clean and compatible with different models of agriculture: organic, biological and integrated pest/pathogen management (IPM) programmes. The main antagonist used in disease control in agriculture is the fungus Trichoderma, a low cost biocontrol agent that can establish it in different pathosystems, has moderate effects on soil balance and does not harm beneficial organism that contribute towards pathogen's control. This biocontrol agent has no harmful effects on humans, wildlife and other beneficial organisms. Trichoderma spp. is safe and effective biocontrol agents in both natural and controlled environments that does not accumulate in the food chain and to which resistance has not been described. Trichoderma strains used as biocontrol agents can act by colonising the soil and/or parts of the plant, occupying a physical space and avoiding the multiplication of the pathogens or producing cell wall degrading enzymes against the pathogens or producing antibiotics that can kill the pathogens or promoting the plant development and inducing the defensive mechanisms of the plant. Antifungal formulations based on Trichoderma strains and proteins require, as in the case of chemical fungicides, a costly and sound registration process previous to their commercialisation. For this reason, many of these biological products are being offered to the farmers under the category of fertilisers and other commercial products that are not tightly regulated, and, hence, they do not offer sufficient guarantee of quality and sanitary control. This fraud must be prosecuted since most of these wrongly registered formulations have not got a Trichoderma inoculums ’, shelf life or other properties stated on their label.

Plant and Soil, 2011

Salt stress is one of the major abiotic stresses limiting crop growth and productivity. This work... more Salt stress is one of the major abiotic stresses limiting crop growth and productivity. This work investigated the potential of five ST isolates of Trichoderma harzianum (Th-13, Th-14, Th-19, Th-33 and Th-50) applied through seed biopriming in reducing the detrimental effects of salinity stress on wheat (Triticum aestivum L.). Growth, physiological and biochemical parameters were studied to characterize salt tolerance. One factor was treatments (T1, T2, T3, T4, T5 and T6) and second factor was four levels of salt stress viz., 0, 2, 4 and 6 dsm −1. In germination test, most of the isolates (Th-14, Th-19 and Th-13) were effective in improving germination percentage and reducing RPG during salinity stress. Seedlings raised from ST Trichoderma isolates had significantly higher root and shoot lengths, CC and MSI than control at all stress levels. The treatments Th-14, Th-19 and Th-13 showed lower accumulation of MDA content whereas proline content and phenolics were higher in treated plants under both nonsaline and saline conditions. Highest MDA content was observed in control at salt stress level of 6 dSm −1. It is concluded that seed biopriming with different salinity tolerant isolates of Trichoderma reduced severity of the effects of salinity though the amelioration was better in Th-14 under present experimental material and conditions.

A total of 22 Trichoderma isolates TCMS 2, 4, 5, 14b, 15, 16, 24, 32, 34, 36, 60, 62, 65 and 93, ... more A total of 22 Trichoderma isolates TCMS 2, 4, 5, 14b, 15, 16, 24, 32, 34, 36, 60, 62, 65 and 93, Th 1,3, 13, 14, 19 and 32, SBIT 32 and 76) were evaluated for their compatibility with dual combinations of copper hydroxide and chitosan (ChoF: liquid formulation) under in vitro conditions to check their maximum tolerance limit. The Trichoderma isolates were screened at graded (250+250, 500+500, 1000+1000 and 2000+2000 ppm) combinations of copper hydroxide and chitosan. At dual combination (250 ppm each), all the tested Trichoderma isolates showed cent per cent growth and thus found highly compatible. Only six isolates viz., TCMS-36, TCMS-60, TCMS-62, TCMS-65, SBIT-32 and SBIT-76 found compatible with exhibiting hundred per cent growth at 500 ppm (each) combination of copper hydroxide and chitosan. At 1000 ppm (each) combination only six isolates were found partially tolerant and none of the isolates was found completely tolerant. Maximum growth was observed in SBIT32 and TCMS-14b (3.6...

Journal of Plant Pathology, 2012

A greenhouse experiment was conducted to examine the effect of seed biopriming with five salinity... more A greenhouse experiment was conducted to examine the effect of seed biopriming with five salinity tolerant isolates of Trichoderma harzianum on the response of rice (Oryza sativa L.) to different salt stress levels. One factor was different Trichoderma treatments (Th-13, Th- 14, Th-19, Th-33 and Th-50) and the second factor was four levels of salt stress viz., 0, 70, 150 and 240 mM NaCl. Growth, physiological and biochemical parameters were determined to characterize salt tolerance. Salt stress adversely affected the studied parameters. However, the data revealed that Trichoderma treatments alleviated the stress condition and significantly increased length and fresh weight of shoot and root, number of leaves, leaf area, photosynthetic rate, chlorophyll fluorescence, chlorophyll content and soil plant analysis development (SPAD) value in comparison to control at all stress levels. Trichoderma treatments also resulted in the alleviation of oxidative damage, as indicated by the decreas...

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service... more This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Morphological and molecular characterization of Eimeria haematodi, coccidian parasite (Apicomplexa:Eimeriidae) in a rainbow lorikeet (Trichoglossus haematodus

Present field experiment was conducted to compare the efficacy of different copper compounds viz.... more Present field experiment was conducted to compare the efficacy of different copper compounds viz.; CuOH (Technical grade), CuOH (Kocide) and Copper sulphate pentahydrate (CuSO4.5H2O) in combination with chitosan (Cs661) and Trichoderma asperellum (Tri) to find out the most effective copper source in the combination for late blight disease management in tomato. Among the three copper compounds, CuOH (TG) was found to be the most effective copper source in the combination. Minimum disease severity (2.33%) was recorded in plots treated with CuOH (TG)+Cs661(Ac)+Tri whereas maximum disease severity was recorded in control plot (40%) after 95 DAT. In terms of other attributes such as yield, reduction in disease progress (A and r value), the most effective treatment was CuOH (TG)+Cs661(Ac)+Tri, which was at par with standard fungicide mancozeb and significantly higher as compared to control. The preliminary results suggest that the combination variants having CuOH as copper source could be...

Annals of Plant Protection Sciences

Journal of Applied and Natural Science

In vitro efficacy of twenty five Trichoderma isolates (twenty were TCMS series viz., TCMS 2, 4, 5... more In vitro efficacy of twenty five Trichoderma isolates (twenty were TCMS series viz., TCMS 2, 4, 5, 12, 14a, 14b, 15, 16, 24, 32, 34, 36, 43, 60, 62, 64, 65, 72, 85 and 93, and five Th series; Th 1, 3, 14, 19 and 32) were ascertained for their antagonistic activity against few major plant pathogenic oomycetes namely, Phytophthora infestans, P. parasitica and Pythium aphenidermatum using dual culture technique. P. infestans was isolated from infected potato leaves and Pythium aphenidermatum from infected brinjal. P. parasitica culture was collected from Central Potato Research Institute (CPRI), Simla. The present study was conducted at Biological Control Laboratory, Department of Plant Pathology, G.B. Pant University of Agriculture and Technology, Pantnagar. All the 25 Trichodrma isolates were found significantly effective against the test pathogens. TCMS-36 and TCMS-72 were found highly effective against P. aphinidermatum with 59.57 per cent inhibition of radial growth of the fungus....

International Journal of Current Microbiology and Applied Sciences

Journal of Applied and Natural Science

Mycotoxins are toxic secondary metabolic products of various fungi, mainly belonging to the gener... more Mycotoxins are toxic secondary metabolic products of various fungi, mainly belonging to the genera Fusarium (Trichothecenes, Zearalenone), Aspergillus (Aflatoxin) and Penicillium (Ochratoxin) and can be found in almost 25% of the world’s agricultural commodities. These compounds are toxic to humans, animals and plants and therefore, efforts should be made to avoid mycotoxin contamination in food and feed. It has been estimated that at least 300 of these fungal metabolites are potentially toxic to animals and humans. In India 50% losses of agricultural commodities are due to postharvest losses. A number of physical and chemical approaches have already been taken to reduce the effect of mycotoxins, but due to certain limitations of physical and chemical strategies prompted search for other solutions to the mycotoxin hazards. Thus, there is an increasing public pressure for a safer and eco-friendly alternative to control these organisms. Consequently, a new approach is applied for mana...

International Journal of Current Microbiology and Applied Sciences

World Population Prospects, 2011). Pests (which include invertebrates, pathogens and weeds) are e... more World Population Prospects, 2011). Pests (which include invertebrates, pathogens and weeds) are estimated to cause between 27% and 42% losses in production for major crops around the world, but this would rise to a staggering 48-83% without crop protection (Oerke, 2006). Therefore, in order to meet the growing food demand, about 15-20 times increase in the use of synthetic pesticides will be required (Oerke, 2006) but the excessive

Plant Physiology and Biochemistry, 2012

Rice is one of the most important food crops drastically affected by drought in lowland rice ecos... more Rice is one of the most important food crops drastically affected by drought in lowland rice ecosystems. In the present study, the impact of drought tolerant isolates of endophytic fungus Trichoderma harzianum on rice response to drought was investigated. Out of 43 Trichoderma isolates studied, only five isolates viz., Th 56, Th 69, Th 75, Th 82 and Th 89 were selected to be drought tolerant as these were able to colonize well on cow dung at low moisture content of 10-20 percent, though two isolates, Th 56 and Th 75, grew even at 5 percent moisture content. Trichoderma-colonized rice seedlings were slower to wilt in response to drought. Colonization delayed drought induced changes like stomatal conductance, net photosynthesis and leaf greenness. Drought conditions varying from 3 to 9 days of withholding water led to an increase in the concentration of many stress induced metabolites in rice leaves and decrease of MSI, while Trichoderma colonization caused a decrease in proline, MDA and H₂O₂ contents, and increase in phenolics concentration and MSI. Among test isolates, Th 56 induced maximum drought tolerance as treated plants recorded only 20-40 percent wilting even at 9 DDS. With or without exposure to drought, colonization by Trichoderma promoted seedling growth, with Th 56 giving the most consistent effect. The primary direct effect of Trichoderma colonization was promotion of root growth, regardless of water status, which caused delay in the drought responses of rice plants.

Plant physiology and biochemistry : PPB / Société française de physiologie végétale, 2012

Rice is one of the most important food crops drastically affected by drought in lowland rice ecos... more Rice is one of the most important food crops drastically affected by drought in lowland rice ecosystems. In the present study, the impact of drought tolerant isolates of endophytic fungus Trichoderma harzianum on rice response to drought was investigated. Out of 43 Trichoderma isolates studied, only five isolates viz., Th 56, Th 69, Th 75, Th 82 and Th 89 were selected to be drought tolerant as these were able to colonize well on cow dung at low moisture content of 10-20 percent, though two isolates, Th 56 and Th 75, grew even at 5 percent moisture content. Trichoderma-colonized rice seedlings were slower to wilt in response to drought. Colonization delayed drought induced changes like stomatal conductance, net photosynthesis and leaf greenness. Drought conditions varying from 3 to 9 days of withholding water led to an increase in the concentration of many stress induced metabolites in rice leaves and decrease of MSI, while Trichoderma colonization caused a decrease in proline, MDA ...