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ThesisItem Open Access Morpho-molecular Characterization and Cross Infection Pattern in Brown Spot Pathogen Infecting Rice (Oryza sativa) and Echinochloa spp.(Barnyard grass)(SKUAST Kashmir, 2023) Tawkeer-un-Nisa; Asha NabiRice (Oryza sativa L.) is the staple food for half of the world’s population. Rice is among the three most important grain crops in the world, and it has a major contribution to fulfil the food needs across the globe. It is cultivated almost in all parts of the world, including USA, Japan, China, India, Indonesia etc. Rice production is greatly influenced by various biotic and abiotic stresses. Among biotic stresses, diseases such as bacterial leaf blight, rice blast, sheath rot, sheath blight and brown spot are the major contributors that lead to yield reduction (Kindo and Tiwari, 2015). Brown spot is historically an important disease of rice. This disease is also found to be associated with a weed, Echinochloa spp. The current study was undertaken to characterize the pathogen isolates from rice and Echinocholoa spp. on morpho-molecular basis, and to study their cross infection pattern. Twenty four brown spot pathogen isolates (twelve from each rice and Echinochloa) were sampled from three rice growing districts (Baramulla, Kulgam and Pulwama) of Kashmir. Variability in colony characteristics and radial growth was observed among the pathogen isolates. Maximum radial growth was observed in isolate BO1 (77mm) and the minimum in isolate BO10 (29.66mm).Among Echinochloa isolates, maximum radial growth was observed in isolate H4 (65.83mm) and the minimum in isolate H2 (47.83mm). The isolates also showed difference in conidial characteristics. Maximum conidial dimensions were observed in isolate BO1 (88.14 x 16.32µm) and the minimum in isolate BO9 (23.19 x 8.73µm). Conidia were light brown to dark brown in colour, shape was straight /curved to slightly curved, and 1-12 septate. Similarly, among the pathogen isolates from Echinochloa, maximum conidial dimensions were observed in isolate H2 (100.25 x 14.09µm) and the minimum in isolate H8 (41.31 x 11.12µm).Conidia were light brown to dark brown in colour, straight /curved to slightly curved, 2-10 septate. Based on ITS sequencing, majority of the isolates were identified as Bipolaris oryzae. Isolate BO9 was identified as Curvularia spicifera, isolate H2 as Exserohilum monoceras, isolate H8 and H9 as Bipolaris victoriae. All the isolates that were selected for cross infection studies showed positive cross infection, however rice isolates were more pathogenic to rice than Echinochloa crus-galli and vice versa. Exserohilum monoceras (isolate H2) was found highly pathogenic on Echinochloa crus-galli, produced only few spots on rice which makes it a potential mycoherbicide for the Echinochloa species. However, more in depth studies are needed in this aspect.ThesisItem Open Access Studies on Foliar Fungal Diseases of Sunflower (Helianthus annuus L) under Kashmir Conditions(SKUAST Kashmir, 2023) Shazia Farooq; Rather, Tariq RasoolFoliar fungal diseases of sunflower i.e. Alternaria leaf blight, Curvularia leaf spot and powdery mildew have been viewed as a possible biotic stress responsible for decreasing yield potential of this crop over the years. This necessitated basic investigations in the host-pathogen interactions vis-à-vis etiology, epidemiology and yield loss assessment. Alternaria helianthi, Curvularia lunata and Erysiphe cichoracearum, as supported by symptomatology, morphology and pathogenicity tests were identified as the causal pathogens of these disease of sunflower in Kashmir, respectively. Alternaria leaf blight disease symptoms on the lamina of the leaves comprised of small scattered brown spots which turn dark brown with yellow halo of 3-5mm in diameter. Mycelium was septate olivaceous green in colour smooth and branched shape. Conidia were septate with 3-8 transverse and 1-2 longitudinal septa light brown in colour. Curvularia leaf blight appeared as small reddish brown spots which became round brown with yellow halo. Mycelium was septate, olive brown in colour, branched and septate. Conidia were black to dark brown in colour with conidiophores septate black to dark brown in colour. The molecular identification using the ITS primers confirmed the identity of the Curvularia lunata showing a similarity of 98.00 per cent with reference sequences. To our knowledge, this is the first report of Curvularia blight on sunflower caused by Curvularia lunata in Jammu and Kashmir and in the country. The sequences of the Curvularia lunata was registered in NCBI Gen Bank under the accession numbers ON668436 & ON668437. The powdery mildew appeared as whitish powdery spots on upper surface of leaves. The severely infected leaves became yellow and dried up. Hyphae were septate and hyaline in colour. The conidia were single celled, hyaline in colour, cylindrical to ovoid in shape whereas conidiophores were straight, unbranched in shape, hyaline in color and septate. The correlation analysis revealed a positive and significant influence of relative humidity and rainfall on Alternaria leaf blight and Curvularia leaf spot whereas it was positive and non significant for powdery mildew . Studies on the requirements of leaf wetness and temperature levels for infection of Alternaria helianthi revealed a minimum leaf wetness of 4 hours and incubation period varying from 2-3 days at 25oC .This hints at the possibility of managing these diseases by altering sowing date such that most or some of the early growth stages enjoy rain free period The data on apparent infection rate(r) revealed that the early growth stage i.e.40 to 47 days after sowing were found to be highly vulnerable to Alternaria leaf blight. The disease progress curve had clearly indicated that the diseases developed very slowly at early crop growth stages and the rate of development increased with increase in age of the crop .This can help in deciding the sowing date and preparing a timely schedule for a fungicidal spray for their effective control of foliar diseases.. The assessment of yield loss in sunflower due to foliar diseases revealed that three sprays of mancozeb 63WP +carbendazim 12% @ 0.25% at 10 days interval starting from 30 days is optimum chemical control of foliar diseases of sunflower under Kashmir conditions and for realizing the maximum seed yield production. The yield losses can be much more under disease favouring weather, hence it should be considered a significant limiting factor in sunflower production. Suitable management strategies need to be evaluated for successful establishment of this potential oilseed crop in Kashmir.ThesisItem Open Access Status and Integrated Disease Management of Fusarium Wilt of China Aster [Callistephus chinensis (L.) Nees](SKUAST Kashmir, 2023) Malik, Sameer Ahmad; Wani, Tanveer AhmadChina aster [Callistephus chinensis (L.) Nees] belongs to the family Asteraceae and is native to China. It is one of the important annual flower crops grown in most parts of the world. It is a hardy annual commercial flower crop grown for loose as well as cut flower purpose. Fusarium wilt is the most important economical disease of China aster. The present investigation entitled “Status and Integrated Disease Management of Fusarium Wilt of China Aster [Callistephus chinensis (L.) Nees]” was carried out at Division of Plant Pathology, FoA, Wadura, during 2021. An extensive survey conducted in three districts of Kashmir valley viz., Srinagar, Baramulla and Anantnag revealed that disease was prevalent in all the three districts with overall mean disease incidence of 33.74 per cent. Symptomatological studies revealed that yellowing of lower leaves started after 21 days of inoculation and wilting and drying up of the whole plant on the 36th day. Cultural characters of isolated pathogen on PDA showed greyish to pinkish colony colour, fluffy texture on upper side and dark violet to pinkish colour on underside of colony. The morphological characters recorded revealed that, mycelium was septate, chlamydospores were globose to subglobose, macroconidia were long sickle shaped with three to eight septa while microconidia were short cylindrical with zero to one septa. Based on symptomatology and morpho-cultural characters, the isolated pathogen was identified as Fusarium oxysporum. Pathogenicity test was proved by Koch’s postulates. Non-systemic fungicides, systemic fungicides and bio-agents were evaluated in vitro. Amongst non-systemic fungicides, mancozeb 75 WP was found to be the most effective against Fusarium oxysporum with mean mycelial growth inhibition of 92.46 per cent followed by captan 50 WP (86.01%) and chlorothalonil 75 WP (60.71%), whereas minimum inhibition was observed in copper oxychloride 50 WP (52.88%). Among systemic fungicides, maximum mean mycelial growth inhibition of 93.49 per cent was observed in carbendazim 50 WP followed by thiophenate methyl 75 WP (91.86 %) and difenoconazole 25 EC (86.02%), whereas least inhibition was observed in kresoxim-methyl 44.3 per cent SC (72.99%). Among bio-agents, maximum mean mycelial inhibition of 78.45 per cent was observed in Trichoderma viride followed by Trichoderma harzianum (73.17%) and Pseudomonas fluorescence (23.17%), whereas least mycelial inhibition was observed in Bacillus subtilis (21.34%). Integrated disease management study revealed that vermicompost @ 100g/pot + Trichoderma viride @ 25 ml cell suspension (2.1 107 cfu/ml)/pot as soil amendment and carbendazim 50 WP as seed treatment and seedling dip was observed to show significantly the least disease incidence of 4.45 per cent, maximum average number of flowers per plant, maximum average flower diameter and maximum average leaf area of 11.47, 7.36 cm and15.56 cm2, respectively followed by VAM @ 50g/pot as soil amendment + carbendazim 50 WP as seed and seedling dip, with the disease incidence of 8.89 per cent, average number of flowers per plant, average flower diameter and average leaf area of 10.93, 6.76 cm and 14.43 cm2, respectively in contrast to control which showed significantly maximum disease incidence of 88.89 per cent, minimum average number of flowers per plant (1.33), minimum average flower diameter (3.66 cm) and minimum average leaf area (9.24 cm2). The study showed fungicides and bio-agents along with soil amendments can effectively be used for managing the Fusarium wilt of China aster.ThesisItem Open Access Substrate Evaluation for Spawn Production and Cultivation of Golden Oyster Mushroom (Pleurotus citrinopileatus S.)(SKUAST Kashmir, 2023) Naziya Batool; Shaheen Kausar JanThe studies to evaluate different substrates for spawn production and commercial cultivation of Golden Oyster Mushroom Pleurotus citrinopileatus were held at Wadura during the year 2021. Seven commonly available substrates namely, barley grains, maize grains, Oat grains, bajra grains, broad beans grain, almond shells and wheat grains (check) were used to evaluate for their suitability in the production of spawn (Pleurotus citrinopileatus). Results showed that maize grains and barley grains were evidence as more efficient substrates with regards to spawn run and spawn texture. The spawn run in maize grains, barley grains and bajra grains was completed in 10.2, 10.8 and 11.4 days, respectively as compared 12.8 days in wheat grains (check). The spawn colour and textures on different substrate showed slight variation, while the spawn colour ranged from ‘brownish-white’ in walnut shells and almond chips, ‘light brown’ in broad beans to ‘white’ in all other cereal grains substrates, Spawn texture ranged from ‘cottony’ to ‘fluffy’ texture was observed. All substrates were found suitable for spawn preparation of Pleurotus citrinopileatus. Eight different substrates namely, Paddy straw, oats straw, maize husk, common bean straw, apple leaf litter, poplar leaf litter, almond hull and apple pomace were evaluated for cultivation of Pleurotus citrinopileatus. All substrate were varied significantly regarding yield, cost benefit ratio and biological efficiency. Paddy straw was found most efficient substrate producing the highest yield (411.8g) followed by almond hull (330.4g). While lowest yield (126.2g) was recorded in apple pomace. The highest biological efficiency (82.36 %) and substrate to yield ratio (1:2.29) was recorded with paddy straw followed by almond hull where biological efficiency and substrates to yield ratio was (66.08%) and (1:1.96), respectively. The lowest biological efficiency (25.24%) and substrate to yield ratio (1:0.08), was recorded with apple pomace.ThesisItem Open Access Studies on the Wilt Complex Disease of Pigeon pea (Cajanus cajan (L.) Millsp)(SKUAST Kashmir, 2023) Heemu Majeed; Baby SummunaFusarium wilt caused by Fusarium oxysporum f. sp. udum is the most devastating disease in pigeon pea. The typical symptoms of the disease appear in plants as gradual or sudden withering and drying of green plant parts exactly as if they were suffering from drought, even though there may be plenty of water in the soil. The present investigation entitled as “Studies on the wilt complex disease of pigeon pea (Cajanus cajan (L.) Millsp)” was carrried out to identify the resistant genotypes against Fusarium wilt and in vitro evaluation of different fungal bioagents isolated from different host crops for management of disease under invitro conditions using pot culture method. In present investigation, Fusarium oxysporum f. sp. udum was found an associated pathogen with wilt disease of pigeon pea. To identify resistant genotypes against Fusarium wilt, a set of 25 genotypes of pigeon pea was screened under epiphytotic condition at FoA Wadura during Kharif, 2022. The disease incidence of 25 pigeon pea genotypes was recorded at two stages viz., seedling and reproductive stage. Under epiphytotic conditions, 4 genotypes were resistant , 12 genotypes were moderately resistant , 2 genotypes were tolerant ,7 genotypes were moderately susceptible at seedling stage. Where as, at reproductive stage 4 genotypes were resistant , 5 genotypes were tolerant , 9 genotypes were moderately susceptible , 7 genotypes were susceptible. At seedling stage, majority of the genotypes were resistant where as, at reproductive stage majority of the genotypes appeared to be susceptible. In vitro evaluation of biocontrol agents revealed that all the fungal biocontrol agents tested in in vitro significantly inhibited the growth of F. oxysporum f. sp. udum, over untreated control but among them ten were found most efficient viz., Penicillium digitatum (27.80mm) followed by Trichoderma atroviridae (28.20mm), Penicillium digitatum (28.70mm), Penicillium polonicum (29.63mm),Trichoderma harzianum (29.77mm), Trichoderma afroharzianum (29.80mm), Penicillium digitatum(29.87mm), Trichoderma harzianum (29.90mm), Trichoderma longibrachiatum (30.23mm), Trichoderma viridae (30.27mm) and caused highest inhibition of the test pathogen. Significantly the maximum pecent inhibition i.e. (69.11 %) was recorded in case of Penicillium digitatum followed by Trichoderma atroviridae (68.67 %) and so on. In in vitro management of the disease in pot culture experiment under greenhouse condition,out of ten bioagents Penicillium digitatum and Trichoderma atroviridae were found most effective antagonists and recorded least wilt incidence i.e., (20.67%) & (28.33%) as against 100 per cent wilt in untreated control, significantly highest wilt reduction was recorded with the application of Pencillium digitatum (79.33%), followed by Trichoderma atroviridae (71.67%).ThesisItem Open Access Studies on Seed Mycoflora of Wheat (Triticum Aestivum L.) and Their Integrated Management(SKUAST Kashmir, 2023) Gajendra Manohariya; Ali AnwarThe present investigation entitled studies on seed mycoflora of Wheat (Triticum Aestivum.) and their integrated management was conducted during 2021-2022. A total of fifteen wheat varieties, NHIVT-303, NHIVT-304, NHIVT-312, NHIVT-315, NHIVT-309, NHIVT-311, NHIVT-306, NHIVT-308, NHIVT-310, NHIVT-301, NHIVT-305, NHIVT-313, SHALIMAR-1 and 2, Wadura. Were collected from seed stores. The seeds were graded on this basis of intensity of discoloration in to four different grades. Among all stored varieties, NHIVT-306 with highest per cent discolouration intensity of 26.00 per cent grades, while as Shalimar-1 possessed lowest per cent discolouration intensity of 05.00 per cent and highest Detection and identification of different fungal pathogens associated with wheat seeds was done by blotter method and agar plate method. A total of five were identified viz. aspergillus sp., Alternaria sp. Rhizopus. fusarium sp.and Trichoderma sp. in both methods. In case of blotter method, NHIVT-315, Wadura showed the highest incidence of seed mycoflora (44%), while NHIVT-306, NHIVT-313 was found to have least incidence of seed mycoflora (16%). Among all fungal pathogens per cent frequency of fusarium sp. was highest (11.04%), while Trichoderma sp. was seen in lowest frequency (08.73%). In case of agar plate method, NHIVT-303 showed the highest incidence of seed mycoflora (96%). While NHIVT-315 was found to have least incidence of seed mycoflora (20%). Among all fungal pathogens per cent frequency of Alternaria sp. highest (09.96%), while as aspergillus sp. was seen in lowest frequency (08.60%). Effect of plant diffusates of Garlic (Allium sativum) on mycelial growth of pathogenic fungi were observed and the measurement of different fungus has been taken on garlic. All five fungus were present on plates. aspergillus sp., Alternaria sp Rhizopus fusarium sp.and Trichoderma sp. Effect of plant diffusates of Stinging nettle (Urtica dioica) on mycelial growth of pathogenic fungi were also seen and the measure of different five fungi was done in micrometer. aspergillus sp., Alternaria sp., fusarium sp..ThesisItem Open Access Epidemiology and Identification of Sources of Resistance against Yellow Rust of Wheat in Kashmir(SKUAST Kashmir, 2023) Bushra Yaqub; Dar, Waseem AliStripe rust, caused by Puccinia striiformis f.sp. tritici, is a potential threat to wheat crop productivity among all the rust diseases. It is a devastating wheat disease that occurs throughout the growing season in wheat areas with cool and moist weather conditions. The present study was conducted on set of fifty-one (51) wheat germplasm lines for screening against yellow rust and to assess the influence of weather parameters like temperature, precipitation, relative humidity and windspeed on yellow rust development. The experimental material included three yellow rust susceptible checks viz., PBW752, PBW343 and HD2733. The wheat germplasm lines were evaluated during Rabi, 2020-2021 and 2021-2022 under augmented block design. The artificial disease epidemic was created in the field following repeated sprays of yellow rust inoculum till appearance of maximum susceptibility on susceptible checks. The germplasm lines were scored following modified Cobb scale. Parameters used as criteria to identify slow rusting included final rust severity (FRS), area under disease progress curve (AUDPC), coefficient of infection (CI) and apparent infection rate (r-value). Among these parameters, FRS, CI and AUDPC were found to be reliable to assess slow rusting in the genotypes whereas apparent infection rate appeared to give unreliable estimations of slow rusting in the current study. The results further revealed that genotypes IC111672, IC111687, IC111691, IC111703, IC111921, IC111939, IC128416, IC128685 and IC111787 had low disease severities (<30%), lower AUDPC values (<30% of the highly susceptible cultivar) and CI values (<20) and as such there rate of disease progress was slow. During both the cropping seasons eight genotypes viz., IC111672, IC111687, IC111691, IC111703, IC111921, IC111939, IC128416 and IC128685 were resistant, one genotype IC111787 was moderately resistant, twenty-seven genotypes, PBW752, IC104538, IC111738, IC111867, PBW343, IC111959, IC11252, IC118721, IC128168, IC128187, HD2733, IC128512, IC128620, IC128640, IC128650, IC111947, IC128409, IC128411, IC128438, IC128654, IC111822, IC111839, IC111914, IC111693, IC111879, IC111968 and IC11177 were moderately susceptible, eight genotypes, IC111717, IC111723, IC111745, IC113725, IC116276, IC128339, IC128666 and ICI38379 were susceptible and 7 genotypes IC113737, IC118722, IC128177, IC128211, IC128215, IC128283 and IC128388 were found highly susceptible to yellow rust. Correlation coefficients indicated that maximum and minimum temperature, morning and evening relative humidity, rainfall and wind speed showed significant relationship with yellow rust severity. Significant R2 value was observed when weather parameters were involved to develop a regression model for stripe rust forewarning. Ninety-eight per cent variability in disease severity due to weather parameters, i.e., maximum and minimum temperature, morning and evening relative humidity, rainfall and wind speed was indicated by R2 value. Slow rusting genotypes, IC111672, IC111687, IC111691, IC111703, IC111921, IC111939, IC128416, IC128685 and IC111787 identified from the study could further be tested for their genetic investigations and their suitability for deployment over space and time. Regression equation can be used for forewarning of disease severity and can be used for timely and effective management of disease so as to reduce the yield losses caused by this particular disease.ThesisItem Open Access Development and Validation of SSR Markers for Marssonina juglandis (Lib.) Magnus Causing Anthracnose of Walnut (Juglans regia L.)(SKUAST Kashmir, 2023) Aswathy Sanjeev; Shah, Mehraj-Ul-DinThe current investigation entitled “Development and Validation of SSR Markers for Marssonina juglandis (Lib.) Magnus Causing Anthracnose of Walnut (Juglans regia L.)” was carried out in Plant Virology and Molecular Pathology (PVMP) Laboratory of Division of Plant Pathology, Faculty of Horticulture, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir, Shalimar, Srinagar. Twenty-five (25) isolates of Marssonina juglandis were obtained from the infected walnut (Juglans regia L.) samples collected from the walnut orchard of SKUAST-K, Shalimar, Srinagar during the year 2022-2023. The symptoms of anthracnose disease initiated simultaneously on current year leaves and twigs and also on fruits during the fruit-set. Symptoms on leaves, twigs and fruits appeared as dark brown to black colored spots, more or less circular, slightly sunken usually bordered by a yellow ring followed by merging of spots at later stages leading to large dead area followed by defoliation. Isolation of the pathogen from the infected samples was attempted by tissue bit and spore transfer methods, where spore transfer method was found to be better than tissue bit method. The morpho-cultural characters of the pathogen on PDA medium at 22±1℃ revealed the circular whitish fungal colony with glabrous aerial mycelial tuft, the development of characteristic concentric zones, well defined lobate margins and radial furrows on further growth of the colony along with black coloured, discoid acervuli in and around the concentric rings. Microscopic observations revealed that the pathogen produced smooth, compact, branched, septate and hyaline hyphae. Conidia were crescent shaped, hyaline with single septation. Pathogenicity test of the pathogen isolates on walnut leaves following detached leaf technique showed an incubation period of 4 to 7 days at 22±1℃. The molecular identification/ confirmation of the pathogen was done using PCR based ITS-1 and ITS-4 markers and the consensus sequence was compared with the available sequences of Marssonina juglandis in NCBI database. The sequence showed maximum similarity (more than 98%) with Gnomonea liptostyla which is the perfect stage of M. juglandis thus confirming the identity of the pathogen as Marssonina juglandis (Lib.) Magnus. The whole genome of the pathogen M. juglandis was used to develop 6884 SSR markers spread on different scaffolds. Validation of SSR markers under in-silico condition was carried out using e-PCR that resulted in 1474 expected polymorphic primers. Among them, 30 SSR’s were randomly selected, custom synthesized and standardized on randomly selected five pathogen isolates under in-situ PCR conditions. The results revealed that, only 17 SSRs could show successful amplification which were further used for amplification of all the 25 Marssonina juglandis isolates collected from different walnut trees. Polymorphic information content (PIC) values ranged between 0.07-0.37, number of polymorphic alleles also varied from 02 to 05. Data analysis using Structure 2.3 software revealed three populations of the pathogen isolates. Colour bar chart also showed the relationship among the 25 M. juglandis isolates dividing them into 3 clusters. Phylogenetic analysis (dendrogram) also revealed that the 25 M. juglandis isolates were divided into three clusters as Cluster-I, Cluster-II and Cluster-III accommodating 9, 7 and 9 isolates respectively, thereby indicating a high level of polymorphism within the pathogen isolates. PCR based detection protocol for the disease diagnosis at early stage of infection using SSR markers MJSSR10 and MJSSR23 were developed for the identification of anthracnose disease of walnut under field conditions for the first time.ThesisItem Open Access Residue Dynamics of Flusilazole and Tebuconazole on Chilli (Capsicum annuum L.) in Kashmir(SKUAST Kashmir, 2022) Kumar, Vinod; Wani, Ashraf AlamThe use of pesticides in large quantities and remarkable biological persistence in environment cause their widespread presence in all elements of food chain, which particularly involves water, vegetation and fish etc. Human beings being at the top of food chain, are exposed to hazardous effects of pesticides from every corner. Contaminated diet even with traces of these harmful chemicals is a chronic unavoidable source of exposure. Besides health benefits, the chillies can also have adversative effects on health if they hold pesticides over the MRLs and are hazardous for consumption. The priority is to detect the pesticide residues in the food in order to avoid the possible risks to human health. It was, therefore thought appropriate to undertake the study on the determination of fungicide residues in chilli and to study the dissipation behaviour of the two fungicides in chilli. The present investigation was, therefore, carried out to study “Residue Dynamics of Flusilazole and Tebuconazole on Chilli (Capsicum annuum L.) in Kashmir” in 2020 at Research Centre for Residue and Quality Analysis (RCRQA), Directorate of Research, SKUAST-K. Flusilazole 40 EC at recommended dosage (0.02%) and double the recommended dosage (0.04%) and tebuconazole 29.5EC at recommended dosage (0.05%) and double the recommended dosage (0.10%) were applied on chilli variety KL-1 (Kashmir long-1) in the field of Division of Plant Pathology, SKUAST-K Shalimar campus. The sampling period for chilli fruit comprised 0, 1, 3, 5, 7, 10, 15, 20, 25 and 30 after application. Flusilazole and Tebuconazole was analyzed by Gas Chromatography and Mass Spectroscopy (GC-MS). The linearity was achieved, with determination coefficients (R2) of 0.998 and 0.9974 for flusilazole and tebuconazole respectively. Mean percent recovery of flusilazole and tebuconazole when fortified at concentrations viz., 0.1, 0.2 and 0.5 mg kg-1 and 0.1, 0.2, and 0.5 mg kg-1 respectively, was found to be 88.26 percent for flusilazole and 87.70 percent for tebuconazole. The studies on dissipation of pesticides in chilli fruit revealed that flusilazole at recommended dose (0.02%) left an initial deposit of 1.713 ±0.004 ppm which dissipated by 99.35 per cent in 15 days and was non-detectable beyond this period. The half-life period (T½) and waiting period (Ttol.) of 1.55 days and 15.19 days were recorded. Flusilazole at double the recommended dose (0.04%) left an initial deposit of 2.634±0.004 ppm which dissipated by 99.46 percent in 25 days and was non-detectable beyond this period. The half-life period (T½) and waiting period (Ttol.) of 3.01 days and 19.83 days were recorded. Tebuconazole at recommended dose (0.05%) left an initial deposit of 1.909±0.004 ppm which dissipated by 88.26 percent in 15 days and was non-detectable beyond this period. The half-life period (T½) and waiting period (Ttol.) of 3.37 days and 4.07 days were recorded. Tebuconazole at double the recommended dose (0.10%) left an initial deposit of 2.666±0.020 ppm which dissipated by 90.05 per cent in 30 days and was non-detectable beyond this period. The half-life period (T½) and waiting period (Ttol.) of 7.76 days and 8.13 days were recorded.
