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Dr. Rajendra Prasad Central Agricultural University, Pusa

In the imperial Gazetteer of India 1878, Pusa was recorded as a government estate of about 1350 acres in Darbhanba. It was acquired by East India Company for running a stud farm to supply better breed of horses mainly for the army. Frequent incidence of glanders disease (swelling of glands), mostly affecting the valuable imported bloodstock made the civil veterinary department to shift the entire stock out of Pusa. A British tobacco concern Beg Sutherland & co. got the estate on lease but it also left in 1897 abandoning the government estate of Pusa. Lord Mayo, The Viceroy and Governor General, had been repeatedly trying to get through his proposal for setting up a directorate general of Agriculture that would take care of the soil and its productivity, formulate newer techniques of cultivation, improve the quality of seeds and livestock and also arrange for imparting agricultural education. The government of India had invited a British expert. Dr. J. A. Voelcker who had submitted as report on the development of Indian agriculture. As a follow-up action, three experts in different fields were appointed for the first time during 1885 to 1895 namely, agricultural chemist (Dr. J. W. Leafer), cryptogamic botanist (Dr. R. A. Butler) and entomologist (Dr. H. Maxwell Lefroy) with headquarters at Dehradun (U.P.) in the forest Research Institute complex. Surprisingly, until now Pusa, which was destined to become the centre of agricultural revolution in the country, was lying as before an abandoned government estate. In 1898. Lord Curzon took over as the viceroy. A widely traveled person and an administrator, he salvaged out the earlier proposal and got London’s approval for the appointment of the inspector General of Agriculture to which the first incumbent Mr. J. Mollison (Dy. Director of Agriculture, Bombay) joined in 1901 with headquarters at Nagpur The then government of Bengal had mooted in 1902 a proposal to the centre for setting up a model cattle farm for improving the dilapidated condition of the livestock at Pusa estate where plenty of land, water and feed would be available, and with Mr. Mollison’s support this was accepted in principle. Around Pusa, there were many British planters and also an indigo research centre Dalsing Sarai (near Pusa). Mr. Mollison’s visits to this mini British kingdom and his strong recommendations. In favour of Pusa as the most ideal place for the Bengal government project obviously caught the attention for the viceroy.

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2013 - 201926
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Subject: Plant Pathology × End date: 2019 × Start date: 2013 ×
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    ThesisItemOpen Access
    Studies on variability and management of Fusarium oxysporum f.sp. cubense isolates causing Panama wilt of banana
    (Dr. Rajendra Prasad Central Agricultural University, Pusa, Samastipur, 2019) Shukla, Daya Nand; Singh, S.K.
    Banana (Musa spp.) is one of the most important fruit crops grown in tropical and sub-tropical region throughout the world. Panama wilt incited by Fusarium oxysporum f.sp. cubense TR4 strain B2 was first time identified in Dwarf Cavendish group of banana cultivar by sending culture to Agharkar Research Institute, Pune. Panama wilt of banana incited by TR4 was found only in Koshi belt, whereas Race 1 and Race 2 of Fusarium oxysporum f.sp. cubense were present in Vaishali belt and this belt was found free from TR4 strain B2 during course of investigation. Inoculum mixed with sterilize soil @ 5% w/w (T5) was found most effective among all the tested inoculation techniques. The cv. FHIA-17 (AAAA) showed some level of tolerance to Fusarium oxysporum f.sp. cubense TR 4 strain B2under sick plot condition during 2017-18 and 2018-19. Fourteen different fungicide and novel chemicals were tested in vitro as well as in vivo conditions. Native (Tebuconazole 50% + Trifloxystrobin 25%) was found to exhibit 100% inhibition in vitro, whereas in pot conditions 86.2% inhibition of Fusarium oxysporum f.sp. cubense TR 4 strain B2 in cultivar Alpan (AAB) was observed. Aqueous extract of Garlic creeper (Adenocalymma alliaceum) was found superior among all the tested botanical extracts, while among bio-agents, Trichoderma viride (Native) was found most effective against the Fusarium oxysporum f.sp. cubense TR 4 strain B2. For integrated management of Panama wilt of banana incited by Fusarium oxysporum f.sp. cubense TR4 strain B2, the maximum inhibition of percent wilt index (93.1%) and percent vascular wilt index (93.4%) were observed in T12 (dipping roots of TC planting materials in Nativo (tebuconazole 50%+trifloxystrobin 25%) (0.2%) for 45 minutes followed by soil drenching with help of Nativo (tebuconazole 50%+trifloxystrobin 25%) (0.2%)@150 ml/pit +Garlic creeper (10%)@ 100 ml/pit and soil application of 50g BCA (Trichoderma viride(107)+Trichoderma harzianum(107)in1:1ratio) at 2nd 4th and 6th and 0, 3rd, 5th and 7th month after planting respectively . The next best treatment was T11 (dipping roots of TC planting materials in Nativo (tebuconazole 50%+trifloxystrobin 25%) (0.2%) for 45 minutes followed by soil drenching with Nativo (tebuconazole 50%+trifloxystrobin 25%) (0.2%)@150 ml/pit +soil application of 50 g BCA (Trichoderma viride (107)+Trichoderma harzianum(107)in1:1ratio) at 2nd 4th and 6th and 0, 3rd, 5th and 7th month after planting with more than 90% inhibition of wilt index and vascular wilt index .However difference between T11 and T12 was non- significant .
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    ThesisItemOpen Access
    Studies on spot blotch of wheat caused by Bipolaris Sorokiniana (SACC.) Shoem
    (DRPCAU, Pusa, Samastipur, 2018) Kumar, Paritosh; Rai, R. C.
    Studies on spot blotch of wheat (Triticum aestivum L.) was carried out to ascertain the status of spot blotch disease of wheat in Bihar, to find out the variability of pathogen in Bihar and to find out a suitable culture media for growth and sporulation of the pathogen. Attempts were also made to estimate the yield losses; and to manage the disease by agronomical manipulations and through fungicides and botanicals. Bipolaris sorokiniana was mainly responsible for causing spot blotch of wheat in Bihar. The disease appeared 5 to 8 weeks after wheat sowing and the symptoms advanced after heading and spreaded very fast. The dark brown necrotic spots (boat shaped) occured on the leaves, crowns and stems with or without yellow halo around these. Lesions on the leaves in the start were few mm in size and extended as elongated dark brown spots and later on coalesced resulting into blight. In severe cases, at flowering stage 60 to 80 per cent leaf areas was turned into necrotic lesions. Intensity of spotting increased with the increase in the age of plants and reached maximum between boot to maturity stage of the crop. Minute spots were also observed on leaf sheaths, nodes, internodes and the glumes. The conidiophores of Bipolaris sorokiniana were light olivaceous brown in colour and emerged both singly or in a group of 2 to 6 from stomatal opening or directly through the epidermal cells of the host, bearing conidia on well defined geniculations and measured 81 to 193 μm long (average 155.20 μm), 6 to 8 μm wide (average 6.70 μm) having 2 to 9 septa (average 6.40). Conidia were formed singly at the tip of conidiophores and were dark olivaceous brown in colour, straight to slightly curved, widest at or near the middle, tapering towards both the abruptly rounded ends and measured 39 to 112 μm long (average 73.90 μm), 13 to 21 μm wide (average 16.70 μm) having 2 to 6 septa (average 3.70). Six groups of B. sorokiniana could be differentiated on the basis of colony colour, colony characteristics and colony diameter establishing the variability in Bipolaris sorokiniana. Remarkable variation in length, width, number of septa in spore and shape of spore were present. Oat meal agar medium and oat meal medium were best suited medium for radial growth and biomass production of Bipolaris sorokiniana, respectively. However, potato dextrose agar was best suited for sporulation of Bipolaris sorokiniana. Yield loss due to spot blotch varied between 7 to 30 per cent and loss in 1000-grain weight between 3 to 23 per cent, depending upon the levels of disease. Delayed sowing favoured incidence of spot blotch irrespective of nitrogen level and more disease developed at higher nitrogen level in all the three date of sowing. Higher levels of nitrogen at all the three date of sowing increased yield and 1000-grain weight and with delay in sowing, yield and 1000-grain weight decreased significantly at all the three nitrogen level. Propiconazole, Hexaconazole and Difenaconazole + Propiconazole at 250 ppm completely inhibited the mycelial growth of B. sorokiniana. Carbendazim and Copper oxychloride also produced cent per cent inhibition but at 500 and 1000 ppm, respectively. Mancozeb could not produce complete inhibition even at 1000 ppm. Spot blotch of wheat could be effectively and economically controlled by two foliar sprays of either Propiconazole or Hexaconazole @ 0.1 per cent at fifteen days interval but on the basis of cost- benefit ratio Hexaconazole had an edge over Propiconazole. Among botanicals eucalyptus leaf extract was highly effective in inhibiting the growth of B. sorokiniana. Garlic clove extract was second best plant extract in inhibiting the growth of B. sorokiniana. All the six plant extracts (garlic clove, eucalyptus leaf, neem leaf, onion bulb, ginger rhizome and black cumin) could significantly reduce PDI when compared with untreated check. Two sprays of garlic clove and eucalyptus leaf extracts @ five per cent were equally effective in reducing disease to 50 per cent and increasing grain yield. Two spray of Propiconazole (0.1 %) at 15 days interval under timely sown condition was best in controlling spot blotch of wheat with significant increase in yield over unsprayed crop. With the delayed sowing (26th December) there was significant decrease in disease control with significantly less yield. Hexaconazole was equally effective and on the basis of cost- benefit ratio, had an edge over Propiconazole.
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    ThesisItemOpen Access
    Epidemiology on alternaria blight of oilseed Brassica
    (DRPCAU, Pusa, Samastipur, 2019) Kuldeep; Choudhary, C. S.
    Oilseed brassica is an important Cruciferae group of crops grown under the wide range of Agro-climatic conditions in India. Among the fungal diseases, Alternaria blight incited by Alternaria brassicicola (Schw) Wilt., considered to be a major disease earlier, is now becoming increasingly destructive and widely damaging in recent years. It is the most ubiquitous, omnivorous and destructive plant pathogen distributed worldwide. Survey conducted at different locations showed its prevalence in Bihar with variable magnitude of incidence ranging from 27.0 to 46.0 per cent. Symptoms appeared on the lower leaves of the plants. The initial symptoms appeared on the lower leaves started as minute brown to blackish lesions which multiply rapidly and later spread to the upper leaves and formed the concentric rings like target board and a zone of yellow halo around the lesions which is very prominent. Isolation of the pathogen was made on PDA medium and identified as Alternaria brassicicola (Schw) Wilt. It produces septate mycelium. The conidiophores are olivaceous, septate, branched, measuring 32-45 μm in length and 6-8 μm in width. Conidia was dark, cylindrical to oblong, muriform without beak measuring 41-54 μm in length and 8-20 μm in width with 5-8 transverse and 0-4 longitudinal septa. Conidia were solitary straight dark, cylindrical to oblong, muriform / ellipsoidal tapering towards end with small beak. The pathogenic behaviour of the fungus was also confirmed after test. Potato dextrose agar (PDA) medium were found most supportive for the growth and dry mycelial weight among both solid as well as liquid media. The temperature range of 20-25⁰C and pH range of 6.0 to 6.5 was most suitable for the growth and dry mycelial weight. Out of thirty-five entries evaluated, no any entries were found resistant and moderately resistant. This might be due to the reason that Dholi centre is hotspot of this disease. The crop sown on October 15, recorded lowest percent disease severity (PDS) of 45.92 per cent in cultivar Varuna and 64.44 per cent in cultivar 66-197-3. Crop sown on October 29, i.e. normal dates of sowing, favoured quick disease development and recorded highest disease intensity 57.03 and 80.74 in cultivar Varuna and 66-197-3, respectively. The 1000 seed weight of cultivar Varuna varied from 3.0 g to 4.0 g and 2.43 g to 3.20 g in cultivar 66-197-3 amongst the different dates of sowing. The cultivar 66-197-3 had smaller seeds than Varuna. Highest seed yield of Varuna (1440 kg/ha) and 66-197-3 (856.67 kg/ha) was recorded when crop was sown timely on 29th October. The temperature from 9.28 to 26.510C and relative humidity 84.19 to 99.61% during above mentioned seasons apparently favoured disease development. The combined effect of different weather variables favoured the disease development causing upto 81 per cent variation in the disease severity of cultivar Varuna and upto 84 per cent variation in cultivar 66-197-3. Both the cultivar, Varuna and 66-197-3 recorded higher disease severity after 50 to 60 DAS and which increased with higher degree at 70 DAS. Plant age had the relationship with development of Alternaria blight severity on leaves, and 50 to 70 days old plant were most susceptible. The cv. 66-197-3 had highest A-value i.e. 807.37 on 100 DAS as compared to the cv. Varuna where the value was 525.87 on 100 DAS in Oct. 29 sown crop. The r-value were varied from 0.190 to 0.230 in cv. Varuna and 0.209 to 0.230 in cv. 66-197-3.
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    ThesisItemOpen Access
    Eco friendly management of mungbean yellow mosaic disease in mungbean
    (DRPCAU, Pusa, Samastipur, 2019) Mishra, Abhay Kumar; Sahni, Sangita
    Mungbean yellow mosaic virus (MYMV) disease is one of the most destructive diseases of mungbean transmitted through whitefly. To combat this disease till now, the thrust was given mainly on chemicals and development of resistant varieties. However, the commercially offered genotypes are only partially resistant. Therefore, the hunt for newer sources of disease resistance needs to be intensified. There is increasing public concern over the level of pesticide residues in food. This concern has encouraged researchers to look for alternative solutions to synthetic pesticides. The use of botanical pesticides is one such method which utilizes various plant products to achieve and ensure good crop health and has become really important in to-days agriculture. India has a rich source of plants that could be harnessed as botanical pesticides. According to Arurveda, the efficacy of plant drugs is increased many folds by extracting in cow urine in place of aqueous extraction. Keeping these facts in view present studies were carried out to find out eco-friendly management of mungbean yellow mosaic disease in mungbean. In the present investigation, a total of 50 genotypes were evaluated along with the susceptible check local mung against the mungbean yellow mosaic virus (MYMV) under natural field conditions in Kharif, 2018. Out of total 50 genotypes, none of the genotypes were found to be free from the disease, only four genotypes namely ML 2459, SML 1828, MH 1344, & SKNM 1504 showed resistant reaction, sixteen genotypes were found to exhibit moderately resistant reaction, fifteen genotypes showed moderately susceptible reaction and fourteen genotypes were found highly susceptible genotype.All together 20 SSR markers were used successfully to detect genetic variation in mungbean genotypes. The SSR marker analysis and disease resistance phenotypes were well correlated. These results clearly indicated that a considerably greater extent of genetic variability exists among different mungbean genotypes and could be used for hybridization programme for developing MYMV resistance. Therefore this study could be quite beneficial for plant breeders and plant pathologist for further utilization and improvement of the mungbean genotypes against MYMV. The results revealed that the cow urine extracts of botanicals found to be best in controlling the MYMV as well as seed yield followed by cow urine extract of Ekka leaves.The highest ICBR (1:7.95) was also recorded in cow urine extract of datura leaves followed by cow urine extract of ekka leaves (1:7.06) and also cow urine extract of datura leaves recorded highest net return (14302.80/ha) followed by cow urine extract of ekka leaves (12702.00/ha) and noticeably, both the treatments had higher net return over chemical check (12265.20/ha). Four resistant genotypes viz., ML 2459, SML 1828, MH 1344, & SKNM 1504 could possibly be utilized as donors to develop MYMV resistant lines by introgressing in agriculturally important but MYMV susceptible genotypes. Consequently, in the near future, the improved varieties may surfeit the sustainable agriculture production in the biotic stress prone areas. The results also showed that three spray of cow urine extract of datura leaves and Ekka leaves effectively manage MYMV disease and give high net return could be effectively exploited for the management of MYMV in mungbean but more studies are required on their integration (resistant genotypes and botanical pesticides) as a component of IDM (Integrated disease management) for reducing dependency on insecticides.
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    ThesisItemOpen Access
    Characterization and management of bacterial wilt of potato
    (DRPCAU, Pusa, Samastipur, 2019) Kumari, Ritu; Ranjan, Rajesh Kumar
    Potato (Solanum tuberosum L.) is one of the important food crops after wheat, maize and rice around the world. ). Bacterial wilt or brown rot, caused by Ralstonia solanacearum, considered as destructive disease of potato crops. It has an extensive host range of ~ 450 crop species across 54 families. In the present research work the bacterial wilt infected potato plant were collected from different location of Samastipur districts of Bihar. 20 strains of R. solanacearum were isolated and identified on the basis of different biochemical characteristics. The strains of R. solanacearum showed fluidal, irregular and creamy white with pink at the centre on TZC medium. The strains of R. solanacearum showed positive result for pathogenicity test and brown rot symptoms in potato tubers. The results of biochemical studies showed that, all the 20 isolates were gram-negative, rod shaped and positive for potassium hydroxide test, oxidase test, catalase test, nitrate reduction test, production of hydrogen sulphide and citrate utilization test but they showed negative reaction for indole test. Race characterization showed that strains of R. solanacearum, causing bacterial wilt disease in potato, belong to race 3 and isolate obtained from wilted tomato plant belonged to race 1. The result of biovar demonstrated that the strain of R. solanacearum collected from different location of Samastipur districts of Bihar belong to bv2 (80%) & bv2T (20%) and tomato isolates belong to bv3. A total of 32 isolates of rhizobacteria were selected on the basis of fluorescent production and evaluated against R. solanacearum in which 22 isolates were found to be effective. Inhibition zone was ranging from 10.33 mm to 31.16 mm, KSP-2 isolates produced highest inhibition zones (31.16 mm). Eleven aqueous and ethanol extracts of botanicals were studied in vitro against R. solanacearum. In both aqueous extract and ethanolic, garlic extract (Allium sativum) at 100% concentration found to be most effective and showed an inhibition zone of about 30.21 mm and 29.77mm respectively. After screening, four aqueous extracts of botanicals (garlic, guava, marigold and turmeric) and four ethanol extracts of botanicals (garlic, guava, marigold and papaya) which showed inhibition zone ≥ 15mm was evaluated against R. solanacearum at1%, 5%, 10% and 15% concentration. Among them garlic showed superiority over all the botanicals extract at all the levels of concentration. Tulsi did not show antimicrobial property in aqueous extracts of botanicals whereas in ethanolic extracts it showed antibacterial property by producing inhibition zone of 14.10 mm. Six antibacterial chemicals (3 antibiotics & 3 bactericides) were evaluated against R. solanacearum. Among the antibiotics Chloramphenicol showed highest antibacterial activity at 100ppm and 250ppm (15.96 and 19.60 mm inhibition zone respectively) whereas at 500ppm Streptocycline produced highest inhibition zone (28.03 mm). Among the bactericides Azoxystrobin showed highest antibacterial activity at all the three concentrations (0.1%, 0.2 % and 0.3 %) produced inhibition zone 10.10mm, 11mm and 12.26 mm respectively.
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    ThesisItemOpen Access
    Novel approach for the management of Tomato fusarium wilt
    (DRPCAU, Pusa, Samastipur, 2019) Maurya, Shivam; Rai, Dinesh
    Tomato (Solanum lycopersicon Mill.) is one of the most popular and important commercial vegetable crop grown all over the world. India ranks second in the area as well as in production of Tomato. In Bihar, tomato is cultivated throughout the year. In Bihar, the area under tomato is 46,000 ha with total production of 7.36 lakh tonnes, with a productivity 16 tonnes/ha. The low productivity is due to use of traditional varieties, diseases and pests. Tomato crop is attacked by several pathogens such as fungi, bacteria and nematodes that significantly affect its growth and yield. Among the fungal diseases, Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici is an economically important and destructive disease of tomato crop. Hence the investigation on “Novel approaches for the management of tomato Fusarium wilt” was undertaken during the course of study as the traditional fungicides had their residues on tomato fruit and harmful to human health. Tomato plants showing typical wilt symptoms were collected from farmer‟s field of Tajpur Village in Muzaffarpur district. The pathogen was isolated in pure form on potato dextrose agar and its pathogenicity was proved. Ten isolates of Trichoderma spp. were isolated from rhizospheric soils of different crops at different location of Muzaffarpur and Samastipur districts of Bihar. These isolates of Trichoderma spp. varied significantly in most of the morphological characters. In vitro evaluation all the Trichoderma isolates showed inhibitory effect on growth of the Fusarium oxysporum f. sp. lycopersici and were effective in controlling the growth of pathogen. The Trichoderma harzianum isolates Th-8 was found to be the most effective in inhibiting the growth of pathogen 64.61%). Among the tested different plant extract, at 10 per cent concentration Garlic extract was found significantly superior in inhibiting the mycelial growth (86.07%), followed by Neem (53.32%), Bramhi (38.8%) and Yam bean seed extract (33.94%). As the concentration of plant extracts increased, the inhibition of test fungus decreases except in Garlic. In vitro compatibility of four fungicides used against F. oxysporum f. sp. lycopersici were tested with effective antagonist Trichoderma harzianum (Th-8 isolate) at the same concentrations by using poisoned food technique. Metalaxyl was found to be best compatible with Trichoderma harzianum (Th-8 isolate), since the per cent inhibition of Trichoderma (Th-8 isolate) was only 6.68 per cent at 1000 ppm concentration. In growth promotion study, Seed bio primed with Trichoderma harzianum (Th8) obtained higher seedling height (12.10cm), fresh shoot weight (10.38g), dry shoot weight (1.20 g), fresh root weight (1.43g) and dry root weight (0.31 g) and was at par with University strain. The efficacy of effective antagonist, chitosan and plant extracts alone or with combination tested in pot against tomato. Among 11 treatments imposed in pot experiment, treatment T10 (Seedling treatment with Carbendazim @ 0.1%) was found to be superior as it recorded least per cent disease index 32.39 per cent. Among the eco-friendly treatments, treatment T4 (Seedling treatment with Trichoderma asperellum @ 5g/lit + Chitosan @ 0.1% followed by its foliar spray) in which 44.66 per cent PDI recorded and was at par with T5 (Seedling treatment with Th-8 @ 5g/lit + Chitosan @0.1% followed by its foliar spray) in which 49.37 per cent PDI observed.
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    ThesisItemOpen Access
    Studies on leaf blotch disease of turmeric (Curcuma longa L.)
    (DRPCAU, Pusa, Samastipur, 2019) kumar, Mukul; Mishra, A. K.
    Turmeric (Curcuma longa L.) known as golden spice as well as “spice of life” has emerged as low volume high value crop. Among various diseases attacking turmeric, leaf blotch disease caused by Taphrina maculans Butler is one of the most serious disease. Turmeric yield losses due to this disease have been recorded upto 37.6-52.9 per cent. Considering the seriousness of this disease, present investigation was carried out on various aspects viz., survey, germplasm screening and evaluation of botanicals, fungicides and resistance inducing chemical against leaf blotch disease of turmeric at T. C. A., Dholi, Muzaffarpur (Dr. Rajendra Prasad central Agricultural University, Pusa, Samastipur, Bihar) during 2018-19. The fungus isolated from the diseased turmeric leaf was confirmed as Taphrina maculans by observing and comparing blastospore measurement with previous reports. Survey results indicated that leaf blotch was observed in all the villages of Samastipur and Muzaffarpur district. Muzaffarpur district was found more prone to leaf blotch disease compared to Samastipur district. There was an increase in the disease incidence during September to November. Among 16 turmeric germplasm screened against the leaf blotch disease, three and eight germplasm showed Resistant and Moderately Resistant reaction respectively. Neem (6% aqueous extract) followed by brahmi (6% aqueous extract) were found most effective plant extract under in-vitro conditions against T. maculans. Under disease management, rhizome treatment alongwith three foliar spray of Tricyclazole 75 WP (0.1%) at fortnightly interval starting from appearance of disease incidence resulted lowest PDI (26.67) and highest rhizome yield (37.85 t ha-1) consequently with 49.99 per cent disease reduction and 55.75 per cent yield increase over control was recorded. Maximum incremental cost benefit ratio (1:16.34) was exhibited by the same treatment.
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    ThesisItemOpen Access
    Integrated disease management of Chickpea Fusarium wilt
    (Dr. Rajendra Prasad Central Agricultural University, Pusa, Samastipur, 2018) Kumar, Sanjeev; Sahni, Sangita
    Chickpea (Cicer arietinum) is one of the world’s major legume crops and suffers substantial damage from wilt disease incited by Fusarium oxysporum f. sp. ciceri (Padwick) with yield loss over 60 per cent. Itis an important soil borne plant pathogen and is difficult to manage by application of chemical. Moreover, the chemical control is costly and leads to residual effect. In the present study, an integrated approach using host plant resistance and integration of three components i.e., cultural (vermicompost amendment), chemical (ZnSO4 and Salicylic acid) and biological (seed bacterization with Pseudomonas spp.) were contemplatedto manage this disease more effectively. A total 55 chickpea genotypes were screened against Fusarium wilt, only one genotype was found to be resistant, however, twelve were found to be moderately resistance (10.1-20 per cent), nineteen were moderately susceptible (20.1-30 per cent), and nineteen genotypes were showed susceptible reaction for wilt disease and recorded more than 30 % wilt incidence and four genotypes showed highly susceptible reaction exhibited more than 50% wilt incidence. The pathogen associated with wilt of chickpea was isolated from the infected plant samples and identified as Fusarium oxysporum f. sp. ciceris based on standard mycological keys. A total of nine pseudomonad isolates were screened for their antagonistic activities against F. oxysporum f.sp. ciceri. All nine isolates exhibited the ammonification property, produced HCN (Cyanide) and IAA (Indole acetic acid) and positive for phosphorus solubilization, except PGPR-Pl, this found to be negative for HCN production. Among the nine isolates, pseudomonad isolates PGPR-WS were best in exhibiting multiple PGPR traits like ammonification, HCN production, IAA production (26.08 mgl-1), and phosphate solubilization (306.51 mgl-1) as well as best in antagonistic activity against F. oxysporum f.sp. ciceri, showed 75.00 % inhibition of growth of mycelia over control and caused total lysis of mycelia in advanced stages of antagonism. Thus screening and identification of novel bioagent PGPR-WS with multifarious activities vividly reflects its potential to suppress F. oxysporum f.sp. ciceriand suggest usefulness of this super bioinoculant as component of IDM of F. oxysporum f.sp. ciceri Among the three control methods, viz., vermicompost amendment, foliar spray with non-conventional chemicals and seed bacterization with PGPR-WS, when used singly, seed bacterization with PGPR-WS was found to be the most effective one among all against F. oxysporum f.sp. ciceri. It is also evident that the biocontrol efficiency against wilt pathogen could be improved by proper combination of vermicompost amendment as well as non-conventional chemicals, as they possess different modes of action against F. oxysporum f.sp. ciceri. Our findings indicated that the high antagonistic activity of PGPR-WS permitted the combination of chemical (non-conventional chemicals like Salicylic acid andZnSO4) and cultural (vermicompost amendment) measures, leading to improved control of the wilt pathogen of chickpea. The combination of all the three control methods was more effective than the lone treatment of the non-conventional chemicals, PGPR-WS, and vermicompost amendment. However, combined application of 15 % vermicompost and seed bacterization with PGPR-WS along with pre-inoculation foliar spray of salicylic acid showed complete protection against F. oxysporum f.sp. ciceri. Among the chemicals tested, Salicylic acid (40 ppm) was usually the most effective one in reducing wilt incidence of chickpea, compared to ZnSO4 (50ppm).
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    ThesisItemOpen Access
    Studies of Grain Discolouration on Rice
    (Dr. Rajendra Prasad Central Agricultural University, Pusa, Samastipur, 2018) Shekhar, Varsha; Rai, Bimla
    Rice (Oryza sativa L.) is one of the most important crop of the world both in terms of areas (433.8 mha) and production (481.54mt) (USDA, 2016). One out of the three people depends on rice for more than half of their daily diet. Rice is the most important staple food in Asia. More than 90% of the world’s rice is grown and consumed in Asia, where 60% of the world’s population lives. Rice accounts for between 35-60 percent of the caloric intake of three billion Asians. Grain discoloration of rice is a complex disease which deteriorates quality of grains. In the present investigation fungi, associated with discoloration of grains were identified as Fusariumsp., Aspergillus sp., Trichoderma sp.,Helminthosporium sp., Rhizhopussp., Curvulariasp. and Altenariasp. In the present study, per cent grain discolouration varied from 36.75 to 69.00. The maximum discolored grain (69 %) was recorded in Rajshree followed by BPT-5204 (57.00%) and RAU-1-16-48 (48 %). The least discolouration was observed in Boro-3 (36.75 %) variety. Detection of mycoflora was done by blotter method, agar plate method and paper towel method. Rajendra Bhagawati recorded (58%) incidence of grain discoloration while Prabhat registered minimum seed infection (30 %) in paper towel method. Santosh and Satyam recorded (83%) and (30%) of seed mycoflora in blotter paper method. In agar plate method Turanta and Gautamrecorded seed mycoflora maximum (60 %) and minimum (21%) respectively. The most wide spread seed mycoflora were Fusariumsp., Helminthosporiumsp.&Aspergillussp. found associated with almost all varieties. Sprint (Carbendazim + Mancozeb) was found highly effective (100 %) against all pathogenic seed mycoflora in-vitro. Effective seed Treatment with neem oil and Trichoderma was also effective.