Department Of Plant Pathology Research Articles

Bioconsortia: A Potential Ecofriendly Bio-Based Product to Enhance the Productivity of the Green Gram

The present investigations on the studies to see the effect of seed biopriming with bacterial consortia in green gram were conducted in a field experiment employing randomized block design with nine treatments and three replications during kharif season 2022-2023 at the Post Graduate Institute, research farm of the Department of Plant Pathology and Agricultural Microbiology, Mahatma Phule Krishi Vidyapeeth, Rahuri, Dist. Ahmednagar, Maharashtra. The result revealed that, among the treatment, T4 recorded the highest average plant height (65.66 cm) and average number of leaves (22.79 plant-1), average number of branches (5.23), average number of pods (30.93), average grain yield (9.18 q ha-1), average stalk yield (24.25 q ha-1) and 1000 seed weight i.e. test weight (33.78 g).

Effects of Bio-inoculation on the Growth of Cabbage as Well as the Disease Progression of Alternaria Leaf Spot

Cabbage is one of the common Cole crop which is widely grown throughout India. It is affected various disease including, Alternaria leaf spot, black rot, club root, downy mildew and powdery mildew. Alternaria leaf spot, caused by Alternaria species such as A. brassicae and A. brassicicola, has been documented on every continent and is a prevalent disease affecting cabbage. Among the various diseases impacting cabbage, it stands out as a major contributor to yield loss, averaging between 32-57%. An experiment Effects of bio-inoculation on the growth of cabbage seedlings, as well as the disease progression of Alternaria leaf spot under challenge inoculation was conducted at Department of Plant Pathology, Rama University, Kanpur during 2023. Result of the study revealed that. application of Trichoderma as a seed treatment led to higher root and shoot dry biomass (0.080 and 0.021 mg/ seedling respectively), higher % increase in root and shoot dry weight (61.25and 82.78%) was found in T1 (Seed treatment with trichoderma harzianum) whereas highest root: shoot ratio (0.222) was reported in treatment T2.

Isolation, Purification and Identification of Xanthomonas oryzae pv. oryzae

The present study was conducted during kharif (July-November, 2020) at the Department of plant pathology, N. M. College of Agriculture, Navsari Agricultural University, Navsari, Gujarat, India to isolate, purify and identify the pathogen responsible for rice bacterial blight. The pathogen was isolated from infected rice leaves and purified through streaking techniques, with its cultural and morphological characteristics utilized for identification. The analysis revealed that colonies grown on nutrient agar media exhibited traits consistent with Xanthomonas oryzae pv. oryzae, appearing raised, creamy yellow, smooth, entire and buttery as cultural characteristics and the bacterium as possessing a rod-shaped structure, gram-negative staining, encapsulation and non-spore formation as morphological characteristics. Furthermore, a pathogenicity test was conducted on the susceptible rice cultivar GR-11, cultivated in pots under controlled conditions within a net house was successfully satisfying Koch’s postulates. Rice (Oryza sativa L.) is one of the important cereal crop and a crucial dietary staple grown extensively in Gujarat, where it plays a significant role in ensuring food security and sustainability. However, rice bacterial blight remains a persistent threat, leading to substantial losses in both quantity and quality. To address this issue the investigation provided valuable insights into understanding the pathogen, thereby contributing to the development of cost-effective solutions for managing rice bacterial blight, which helps in increasing crop yield to the rice growing farmers of Gujarat.

Prevalence and Epidemiology of Apple Powdery Mildew in Northwest Himalayan Region of Himachal Pradesh

A survey was conducted to assess the incidence and severity of powdery mildew of apples during April to July of 2020 and 2021 at the different locations of Kinnaur district, Himachal Pradesh, India. Assessment scale of Hofer et al. (2019) with slight modification was used for cultivar screening. Apple seedlings were grown in the pots in the polyhouse of the Department of Plant Pathology in order to test the pathogenicity of Podosphaera leucotricha. Pathogenicity was confirmed through inoculation tests by gently pressing diseased leaves on young leaves of five asymptomatic, potted one-year-old Gale Gala seedlings of apple. Five non-inoculated plants were used for a control treatment. Overall, twenty different apple cultivars were screened against powdery mildew planted under field conditions at Krishi Vigyan Kendra Sharbo, Kinnaur, Himachal Pradesh, India. Out of these cultivars, five cultivars viz. Red Delicious, Royal Delicious, Red Velox, Auvil Early Fuji and Oregon Spur II, were found to be less susceptible to Podosphaera leucotricha, causing powdery mildew of apples, while Granny Smith, Golden Delicious, and Gale Gala were found extremely susceptible. Gala series of cultivars were found to be extremely susceptible to the pathogen. Incidence of the disease ranged from 25.42% to 53.80% and severity from 39.75% to 66.25%, respectively. According to the present study the disease initiated during the first week of May and peaked in the month of July in district Kinnaur. Temperatures between 18–24°C and RH between 50–65% were found to be favourable for the disease development. The conditions in the region were found to favourable for disease development and spread.

Effect of Antagonists and Botanicals Against Xanthomonas oryzae pv. oryzae In Vitro

The present study was conducted during kharif (July-November, 2020) at the Department of plant pathology, N. M. College of Agriculture, Navsari Agricultural University, Navsari, Gujarat (396 450), India to examine the efficacy of four recognized antagonists and a control against Xanthomonas oryzae pv. oryzae. By employing paper disc method the results indicated that Bacillus subtilis exhibited the highest radius of inhibition. Following this, Pseudomonas fluorescens, Trichoderma harzianum and Trichoderma viride were identified as the next most effective antagonists. In addition, ten different botanical extracts, including a control, were examined for their inhibitory impact on the bacterial growth of bacterial blight at a 5% concentration using the poisoned food technique. Among these extracts, garlic clove extract demonstrated the maximum inhibition radius against the pathogen, followed by tulsi leaf extract and neem leaf extract, attributed to potent toxic principles. Conversely, extracts from karanj, nilgiri, dhatura, jetropha and rhizomes of ginger, turmeric and onion bulb were found to be less effective against Xanthomonas oryzae pv. oryzae. The goal of this study provided valuable insights to determine the potential antagonists and botanicals against bacterial blight of rice in vitro with experimental design of Completely Randomized Design which offer a cost effective solution for the disease, in increasing crop yield to the rice growing farmers of Gujarat without disturbing ecosystem and without creating the problems of pollution.

In vitro Inhibition of Rhizoctonia solani Radial Growth by Native Mycoflora: Implications for Root Rot Disease in Chili

In the course of the study, native bioagents isolated from the rhizosphere of the chili crop were used to manage the soil-borne pathogens Rhizoctonia solani. The study was conducted in the laboratory of the Department of Plant Pathology and Nematology, RPCAU, Pusa, Bihar in the year 2020-23. The soil microflora (fungal and bacterial) was isolated from the rhizosphere of Chili and screened in vitro by evaluating their antagonistic potential against Rhizoctonia solani, and resultantly two fungal and two bacterial isolates were found most effective in inhibiting the mycelial growth of the pathogen over control. The maximum percent inhibition was recorded in the case of Trichoderma harzianum (71.98%) followed by Trichoderma viride (62.54%) and among the bacterial isolates maximum inhibition was recorded in the case of RB1 that inhibit (69.38%), followed by RB6 (66.42%). Overall, these findings suggest that the combination of Trichoderma and Bacteria could be an effective and sustainable method for reducing the radial growth of Rhizoctonia solani causing Root rot disease in chilli. Rhizoctonia solani was established as a causal organism of chili. The use of Bio-control agents is an eco-friendly approach and a good option to manage soil borne phyto-pathogens. These biological control agents either use the mechanism of antibiosis or mycoparasitism against the fungal pathogen. Evaluation of Trichoderma spp. and Bacterial isolates against Rhizoctonia solani showed that significantly reduced the mycelial growth of Rhizoctonia solani in vitro.

Influence of Different Culture Media on Growth and Sporulation of Colletotrichum capsici

Aim: To know the best culture media for growth and development of Colletotrichum capsici causing chilli anthracnose.
 Study Design: Twelve different culture media were selected and three replications were maintained.
 Place and Duration of Study: Department of Plant Pathology, University of Agricultural Sciences, Raichur, Karnatka, which was carried out in the year 2021-2023.
 Methodology: The laboratory study was conducted to know the best nutrient media for the growth and sporulation of the pathogen. The pathogen was isolated from infected chilli fruit using tissue isolation technique and pure culture was maintained. Twelve different nutrient media were selected and tested for the growth and sporulation of the pathogen in three replications.
 Results: Among twelve media tested, Red chilli dextrose agar have promoted the maximum growth of C. capsici (90.0 mm), which was followed by carrot dextrose agar and potato carrot agar (89.50 mm). Green chilli extract agar significantly promoted minimum growth of C. capsici (33.50 mm), which was followed by red chilli extract agar (48.00 mm) and Sarbouraud’s agar (48.50 mm). The cultural characters were varied among the media.
 Conclusion: Potato dextrose agar and carrot dextrose agar media were proved to be best media for growth and sporulation of Colletotrichum capsica.

Potential of Native Microflora of Banana, Chili and Garlic Intercropping System for Bio-control of Rhizoctonia solani Causing Root Rot of Chili

Root rot disease caused by Rhizoctonia solani is a serious problem in chili pepper production, leading to significant crop loss and reduced yield. The chemical control method for controlling this soil borne disease is not preferred due environmental concerns and harmful effect on beneficial soil microflora. Therefore, there is an increasing demand for safer and sustainable approaches. In the present investigation which was conducted in laboratory of the Department of Plant Pathology and Nematology, RPCAU, Pusa, Bihar during the year 2021-23, the microflora isolated from the rhizosphere of Banana+Chili+Garlic intercropping system were evaluated for their effectiveness against Rhizoctonia solani causing root rot in Chili. In course of study the isolates of Trichoderma and Bacillus significantly reduced the radial growth of Rhizoctonia solani. The maximum growth inhibition was recorded by the Trichoderma isolate - GITr5 causing 71.40 % inhibition of the pathogen growth. This was followed by CITr4 with 67.41% and BITr1 with 62.86 %inhibition of the pathogen. Among the bacterial isolates, The isolate CIRB1 was found to inhibit the target pathogen by 71.22% followed by BIRB8 causing 66.92% inhibition of the pathogen.

The Pathogenicity Test, Cultural and Morphological Characterization of Anthracnose (Colletotrichum lindemuthianum) of Green Gram (Vigna radiata L. Wilczek)

Aims: The objective of this study was to identify the appropriate anthracnose fungus of green gram using symptomatology, identification, pathogenicity test and characterization of samples.
 Study Design: Pathogenicity test, cultural and morphological characterization.
 Place and Duration of Study: The laboratory studies were conducted in the Department of Plant Pathology, N. M. College of Agriculture, Navsari Agricultural University, Navsari, Gujarat during rabi 2020-21.
 Methodology: The sample was collected and subjected to isolation, purification and identification of pathogen. Four different pathogenecity tests were conducted to verify the pathogen causing anthracnose of green gram. On the other hand, the cultural and morphological characteristics of pathogen were studied. 
 Results: The pathogenecity test confirmed that the pathogen as Colletotrichum lindemuthianum in all four tests. Spraying inoculum after needle pricking and carborandum powder producing 100% infection in inoculated plants while 96% in spraying spore suspension without any abrasion. The less per cent of infection was observed in seed inoculated plants. The cultural studies of C. lindemuthianium shown sub-aerial whitish-to-pink cottony growth and pinkish-to-brown pigmentation under the culture plate. The morphological study of C. lindemuthianium observed as single-celled, hyaline, cylindrical, and smooth with oil globules. The acervuli were blackish brown and measure 181.3 × 254.6 µm. The setae were visible through the conidial mass with 1-3 septations.
 Conclusion: A study on green gram anthracnose confirmed C. lindemuthianum as pathogen in all four pathogenicity test with needle pricking and carborandum powder producing 100% infection in inoculated plants while 96% in spraying spore suspension without any abrasion. Cultural studies revealed whitish-pink cottony growth and pinkish-brown pigmentation. C. lindemuthianium was morphologically observed as single-celled, hyaline, cylindrical, smooth, with oil globules, blackish brown acervuli, and visible setae through conidial mass with 1-3 septations. Therefore, these findings are important for identifying the anthracnose disease of green gram.

Effect of Different Culture Media on Growth and Establishment of Phomopsis vexans Inciting Fruit Rot of Brinjal (Solanum melongena L.)

The fruit rot caused by Phomopsis vexans (Sacc. & Syd.) Harter is a destructive disease of brinjal and is considered to be a major constraint for its production. The present study was carried out at the Centre of Excellence for Sanitary and Phytosanitary, Department of Plant Pathology, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut, for the evaluation of different culture media on growth and development of Phomopsis vexans. The study showed the maximum radial growth on OMA (90.00 mm), followed by PDA (88.20 mm) and Sabouraud Dextrose Agar (80.16 mm). The pycnidial densities were recorded as excellent on OMA and TFA, good on PDA, SDA, BFA, and MEA, and poor on YMA and CMA media with brown to black colour, while on RSA and WA they were absent. The colony colour were observed on several cultural media with circular and irregular shapes. The maximum pycnidial size was recorded on TFA (454.35×316.18 µm), followed by SDA (415.60× 296.26 µm) and BFA (324.72×368.84 µm), whereas the minimum was recorded on CMA (289.48×128.52 µm), followed by MEA (308.66×140.25 µm). The α-conidia were noticed to be sub-cylindrical and elliptical in shape and largest conidia observed on TMA (10.6×2.6µm), followed by BFA (9.8×2.6µm), and the smallest on RSA (6.1×1.6µm). The number of conidia was recorded highest on OMA (29.) medium and lowest on RSA (12.63). The β-conidia were not observed in this study. The number of guttullae were recorded 1-2 in all tested culture media except TFA and SDA, which had 2-3.

Performance of Clusterbean (Cyamopsis tetragonoloba L.) Varieties under Different Temperature and Relative Humidity Profiles

A study was performed at Department of Plant Pathology during year 2020, CCS Haryana Agricultural University to find the effect of different growing environments on temperature and humidity profile development, yield and its attributes in clusterbean crop. Three varieties of clusterbean varieties i.e. HG 365 (V1), HG 563 (V2) and HG 2-20 (V3) with each sown at three different dates of sowing i.e first (D1), third (D2) and fourth (D4) week of July in factorial randomized block design and replicated thrice. The diurnal range of temperature profiles at the emergence stage and flowering stage were higher in the crop sown in the first fortnight of July as compared to the second and third fortnights of July. Crops sown in the fourth week of July had a greater diurnal range of relative humidity profiles at the vegetative and pod formation stage while at flowering stage higher diurnal variation were present in first week of July sown crop. However, among different cultivars of clusterbean, no variation in temperature and humidity profile were observed. Significantly higher number of branches per plant, number of pods per plant, pod length, number of seeds per pod, harvesting index, grain and straw yield were found in D1 (first week of July) and V2 (HG 563) as compared to remaining dates of sowing and varieties, respectively.

Distribution of Mosaic Disease in Ridge Gourd (Luffa acutangula (L.) Roxb.), Characterization of Associated Virus and Screening for Virus Resistance

Aims: A survey was conducted in the ridge gourd growing areas of Kasaragod, Kannur and Kozhikkode district, India, to assess the prevalence of virus diseases. Molecular detection and characterization indicated the presence of mixed infection of Tomato leaf curl New Delhi virus (ToLCNDV) and Cucumber mosaic virus (CMV) in infected samples of ridge gourd collected from surveyed locations. Additionally, a screening of popular varieties/hybrids was undertaken to identify resistance sources against the Begomovirus in Ridge gourd.
 Study Design: CRD design for screening for resistance genotype.
 Place and Duration of Study: Department of Plant Pathology, College of Agriculture, Padannakkad. November 2022 - 2023.
 Methodology: Twenty-five ridge gourd plants were selected from a field and scored during survey. Major weeds and insects in and around the location were collected and identified. Screening for resistance was carried out in vitro by grafting infected scion on to healthy ridge gourd plants. Begomovirus infections were confirmed by polymerase chain reaction (PCR) using specific coat protein primers. Presence of CMV was detected using specific primers.
 Results: Disease incidence (DI) of surveyed locations ranged from 5.3-100 per cent and vulnerability index (VI) from 26.57-84.08. Kunjathur, Thalangady, and Hosabettu areas of Kasaragod district recorded the highest incidence (100%). The highest VI (84.08) was recorded in Thalangady (Kasaragod). Bemisia tabaci and Aphis gossypii were the associated insects and Synedrella sp., Ageratum conizoides and Alternanthera sp. were the associated weeds.
 Screening of varieties indicated moderately susceptible reactions of RG7 and RG10 after 60 days of grafting. PCR based molecular detection of ToLCNDV using coat protein specific primers yielded amplicons of approximately 575 bp. All the isolated sequences were found to be related to ToLCNDV on sequencing and blast analysis. Phylogenetic studies revealed that isolates from Thrikaripur, Mavichery, and Poolacode were closely related to each other. Cucumber mosaic virus, a RNA virus was also detected from isolated samples using specific primers of CMV with an amplicon size of 400 bp.
 Conclusion: The study revealed that the ridge gourd cultivated in areas of Kasaragod, Kannur and Kozhikode were infected with ToLCNDV and CMV; RG7 and RG10 were moderately susceptible among the varieties and hybrids screened. The presence of the begomovirus was detected in weeds indicating its role in perpetuation and spread of the virus disease in the field.

Improvement in Biocontrol Ability of Trichoderma Through Chemical Mutation and Gamma Irradiation for The Control of Soil Borne Pathogens

Biocontrol agent like Trichoderma viride was acclaimed as effective, eco-friendly and cheap, nullifying the ill effect of chemicals, These biocontrol agents are identified to act against on array of important soil borne plant pathogens viz.,Sclerotium rolfsii, Rhizoctonia bataticola and Fusarium oxysporum f. sp. ciceri etc.” Improvement in biocontrol ability of Trichoderma viride through mutation” was carried at Department of Plant Pathology, during 2019-2020. The antagonistic ability of a biocontrol agent was determined by its physiological state so that change in physiological or genetically conditions could alter the antagonism. Hence the genetic modification using mutagenesis offers the potential for producing improved bio-protection is likely to enhance their biocontrol capabilities against soil borne pathogen. Mutagenesis by chemical i.e. Ethyl Methyl Sulphonate (EMS) @ 100, 150, 200 and 250 µl/ml and time interval at 30, 45 and 60 minutes. The influence of gamma irradiation on improving production of antifungal metabolites and biological proficiency of the biocontrol agent against soil borne pathogen. Trichoderma viride were irradiated in different dose of gamma radiation (cobalt-60) @ 0, 20, 30, 40 and 50 k-rad. for induced mutation. Sixteen Trichoderma viride mutants were obtained after chemical mutagenesis and gamma irradiation and tested for their antagonistic activities in vitro. Morphological character of efficient mutants was tested up to six generation to check their stability. Among these, four stable mutants viz., TVME 2b, TVME 2c, TVME 3c and TVGM1 were proved as effective antagonists against Sclerotium rolfsii, Rhizoctonia bataticola and Fusarium oxysporum f.sp. ciceri basis of their maximum bioefficiency. Mutants TVME2b, TVME2c, TVME3c and TVGM1 exhibited the highest inhibition to mycelial growth of Sclerotium rolfsii with an inhibition percentage 64.76, 64.22, 63.08 and 62.93% respectively. Rhizoctonia bataticola was inhibited to the extent of 63.47, 60.87, 61.93 and 61.02% by relative mutants, while Fusarium oxysporum f. sp. ciceri was restricted and recorded 63.50, 62.88, 62.03 and 60.74% respectively. The highest chitinase enzyme units/mg of protein i.e. 0.64, 0.63, 0.63 and 0.62 was exerted in TVME2b, TVME2c, TVME3c and TVGM1 having respectively. However, TVME1c contains 0.37 enzyme units; it showed maximum ability against pathogens. hence present study proved that mutagenesis is the efficient tool for improving bioefficiency of Trichoderma viride, a biocontrol agent.

Prospecting of Bioagents and Screening of Varieties against Anthracnose of Green Gram

Aims: Anthracnose poses a significant threat to green gram cultivation in India. This study focused on evaluating various bioagents and cultivars efficacy in combating Collectotrichum lindemuthianum through in vitro bioassays and glasshouse investigations.
 Study Design: Dual culture technique and screening of varieties
 Place and Duration of Study: The laboratory studies were conducted in the Department of Plant Pathology, N. M. College of Agriculture, Navsari Agricultural University, Navsari, Gujarat, India during 2020–2021.
 Methodology: The dual culture method was employed to gauge the potency of biocontrol agents, while variety screening helped to identify resistant and susceptible green gram varieties against C. lindemuthianum.
 Results: In vitro assessments revealed that among the five biocontrol agents tested, Trichoderma virens (87.63%) and T. viride (85.41%) exhibited significant suppression of mycelial growth compared to the untreated control. However, in greenhouse pot culture experiments involving eight different genotypes, none were found to be immune to green gram anthracnose. Nevertheless, Pusa 1431, KM-2328, TARM-18, and GM 6 exhibited a resistant response against anthracnose, while BPMR-145 and Vaibhav proved susceptible to the disease.
 Conclusion: Biocontrol agents are cost-effective and safe for disease management, while integrating resistant varieties is a solid strategy. These high-yielding, environmentally safe, and economically viable methods benefit farmers. Recognizing resistant genotypes is crucial for breeding disease-resistant varieties, as they limit field spread and reduce conidia production of C. lindemuthianum causing green gram anthracnose.

Assessment of Rapeseed-Mustard Varieties for Resistance against White Rust (Albugo candida) Infection

The increasing prominence of rapeseed-mustard on the global stage as vital oilseed crop is attributed to its high yield, low moisture requirements, cost effective production, and adoptability to diverse farming condition indicating the potential for a forthcoming yellow revolution role in India's oilseed production, facing challenges from various factors affecting yield and seed quality. Notably, white rust stands out as a significant biotic stressor, causing substantial losses in both yield and seedily, 17–34% yield particularly in oil content. To address this, utilizing resistant varieties is the most cost-effective and environmentally friendly approach for disease management. However, the available resistant sources are limited. In a recent study during the Rabi seasons of 2021-22 and 2022-23, thirty rapeseed mustard genotypes were assessed under white rust prevalent conditions. Out of 30 genotypes tested, none were found to be free of white rust disease infection and none were classified as resistant. However,11genotypes were registered as as moderately resistance, while, 19 genotypes fell under the were in the susceptible category. Promisingly, some genotypes exhibited resistance to white rust, offering potential for developing superior cultivars to effectively manage the disease in regions where mustard cultivation is prevalent. Aims: The study aimed to evaluate 30 rapeseed-mustard genotypes during the Rabi sessions of 2021-22 and 2022-23, focusing on their resistance to white rust. The primary objective was to identified genotypes with potential resistant traits, contributing to the development of superior cultivars for effective white rust management in regions where rapeseed-mustard cultivation is prominent. Study Design: Randomized Block Design. Place and Duration of Study: Experimental field of the Department of Plant Pathology, College of Agriculture, BUAT, Banda session 2021-22 and 2022-23. Results and Conclusion: None of the tested genotypes were found to be entirely free from white rust infection, and none of these achieved under resistance. However, the study identified 11 genotypes as moderately resistance and 19 genotypes fell into the susceptible category. Despite the challenges posed by white rust, sum genotypes demonstrated resistance, offering promising potential for the development of advanced cultivars. This finding holds significant for regions where rapeseed-mustard cultivation faces the threat of white rust, providing the basis for future efforts enhancing crop resilience and productivity.

Evaluation of Antifungal Potential of Phytoextracts and Chemicals against Root Rot of Soybean caused by Rhizoctonia solani

Rhizoctonia solani is a soil-borne fungal pathogen that causes root rot diseases in various crops. The soybean crop is also susceptible to this pathogen, resulting in severe yield losses. Due to its soil-borne nature, controlling infestations with a single treatment is challenging. Therefore, the current study was designed to evaluate synthetic chemicals and phytoextracts as an integrated approach to manage soybean root rot caused by R. solani under laboratory and greenhouse conditions. Diseased samples were collected from the field area of the University of Agriculture, Faisalabad. The pathogen was isolated and identified as Rhizoctonia solani using available literature at the Phytopathology Laboratory, Department of Plant Pathology. Four fungicides (Tilt, Cabriotop, Amister top, and Champion) and phytoextracts (Garlic, Ginger, Turmeric, and Eucalyptus) were investigated at three different concentrations under in vitro conditions using the poisoned food technique. The findings revealed that significant inhibition of mycelial growth was observed with Tilt fungicide (4.5 mm) and Garlic extract (12.92 mm) at all concentrations. Subsequently, these two were further investigated under greenhouse conditions, both individually and in combination. Results indicated that the combination of Tilt + Garlic was highly effective against soybean root rot, with the lowest disease incidence of 4.52%, followed by the sole application of Tilt (13.35%) and Garlic (15.75%), respectively. Therefore, it was concluded that using more than one treatment in an integrated approach can be more effective in controlling soil-borne pathogens such as R. solani.

In-vitro Evaluation of Fungicides and Botanicals against Uromyces ciceris arietini Inciting Chickpea Rust Disease

Chickpea, commonly known as gram is one of the important pulse crops in India. The crop faces numerous disease attacks, resulting in losses to both quality and quantity. Among the diseases, rust caused by Uromyces ciceris arietinum, is a sporadic disease of chickpea. Considering the notoriority of disease A study was conducted at department of plant Pathology and Agril Microbiology, PGI MPKV, Rahuri during 2021-22 which aimed to assess the efficacy of fungicides against the pathogen causing rust disease under in vitro conditions. Among five fungicides, Tebuconazole 50% + Trifloxystrobin 25% w/w WG and Azoxystrobin 18.2% + Difenoconazole 11.4% w/w SC were found cent per cent effective against U. ciceris arietini, which completely inhibited uredospore germination at all three concentrations, viz. 50 ppm, 100 ppm, 500 ppm. However, Propiconazole 25% EC, Tebuconazole 25% EC and Hexaconazole 5% SC were found cent per cent effective against test pathogen only at 500 ppm. Among botanicals, Azadirachtin and Pongamia oil showed effective treatments to some extent. Maximum uredospore germination (63%) was recorded in control (Tap water).

Compatibility Analysis of Mushroom with different Botanicals in In vitro Condition

White button mushroom [Agaricus bisporus (Lange) Imbach] is the most popular cultivated edible mushroom, fetching high price and still dominating in Indian and International market. However, the limiting factor for its successful cultivation is the occurrence of competitor moulds. The present investigations were carried out in the laboratory Department of Plant Pathology, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj, Uttar Pradesh. In this experiment different botanical (seed extract) viz., Trachyspermum ammi (Ajwain), Foeniculum vulgare (Saunf), Anethum graveolens (Soa), Trigonella foenumgraecum (Methi) were evaluated to test their compatibility with Agaricus bisporus. The botanicals (seed extract) were evaluated in vitro through poison food technique at 10, 20 and 30% concentrations and 24, 48 & 72 hours of incubation. The maximum radial growth of Agaricus bisporus was observed in T0-Control (Agaricus bisporus) (16.45mm), (17.12 mm) and (17.22 mm) and minimum in T1 - Trachyspermum ammi (Ajwain) (1.46mm), (0.83mm) and (0.60mm) at 10, 20 and 30 percent concentration respectively. Maximum percentage of inhibition was observed in T1 - Trachyspermum ammi (Ajwain) (91.11%), (95.13%) and (96.50%) at 10, 20 and 30 percent concentration respectively.

Biological and Chemical Management Strategy to Control Brown Spot Disease in Rice Caused by Bipolaris oryzae

The main objective of this study was to assess the effectiveness of various fungicides in managing rice brown spot, a common fungal disease in India that can reduce crop yield and seed quality. During 2020-21 crop seasons, a research project was conducted in the experimental plot of the Department of Plant Pathology at the College of Agriculture in Rewa, Madhya Pradesh, India. Different treatments involving fungicide application at various rice growth stages were implemented. The results showed that all treatments involving fungicides significantly reduced the incidence of rice brown spot in-vitro condition and increased crop yield when compared to the control group. Among the fungicides, Difenoconazole 25% EC at a concentration of 200ppm proved to be highly effective in controlling the growth of the fungal mycelium. In in-vivo condition, the treatment involving T4, which includes seed treatment with the bio-control agent Trichoderma viride (10g/kg seeds), the application of Trichoderma viride (10g/l) at 15-20 days after transplanting, and the application of propiconazole (1g/l) at the booting exhibited the highest level of reduction in the incidence of brown spot disease, amounting to 13.6 per cent. The integrated management approach are very effective to control the brown spot disease in rice.

Effect of Different culture media, temperature and pH for growth of Rhizoctonia solani causing Sheath Blight Disease in Rice Mat Nursery

Over the last decade Sheath Blight of Rice as a major constant in rice mat nursery production has been identified globally and integrated disease resistance strategy for Sheath Blight of Rice has been primary focus in south east Asia particularly in the kharif and rabi rice growing areas like Bangladesh, Eastern India, Terai region of Nepal and Pakistan. Rhizoctonia solani (Kuhn.) is the causal agent of Sheath Blight Disease in Rice Mat Nursery. It is a soil inhabiting fungal pathogen which favors hot and humid temperature. Keeping in view the consequentiality of the disease due to transmute in climatic conditions, studies were conducted on the cultural and morphological diversity of the pathogen in different media, pH and temperature conditions. This research was conducted at Department of Plant Pathology in Uttar Banga Krishi Viswavidyalaya. The fungus Rhizoctonia solani gives highest mycelial growth on PDA (Potato dextrose Agar) media which is 60.78 mm and it is followed by Glucose peptone Agar media (55.33 mm) and V-8 juice Agar media (51.11 mm) whereas the lowest growth was observed in Czapek Dox Agar media (19.66 mm) followed by Oat meal Agar media (26.66 mm). In different pH, maximum mycelial growth was observed at pH 7 i.e., at neutral pH (62.33 mm) while they showed less growth in too acidic pH i.e., at 4 and at too high pH i.e., at pH 10. In different temperature, the highest mycelial growth was observed at 26⁰C (62.91 mm) to 28⁰C (62.05 mm) i.e., they prefer normal temperature for their growth.