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ThesisItem Open Access Early detection and management of white rust disease (Albugo candida) in rapeseed mustard(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Gairola, Kalpana; Tewari, A.K.Among various diseases reported to occur on rapeseed mustard, white rust caused by Albugo candida is considered as one of the most important disease due to its destructive nature, wide distribution and grain yield losses of 17-34 per cent. The present investigation was carried out with the objectives of: early detection of A. candida, the cause of white rust disease; evaluation of rapeseed-mustard genotypes in field and in glasshouse (at cotyledonary and true leaf stage) and evaluation of some new fungicides for the effective management of the disease. The early detection of A. candida was done by PCR-based assay and light microscopy. In PCR based assay the primers ITS1 (3’-GAGGGACTTTTGGGTAATCA-5’) and Short ITS JV34 (3’- CGCCATTTAGAGGAAGGTGA-5’) and JV37 (3’-GTCAAGCAAAACAT-5’) were used to amplify the ITS region of A. candida and Alternaria brassicae. PCR amplification of A. candida from inoculated symptomatic and asymptomatic leaves yielded PCR products of 1200 bp and 600 bp of ITS1 and Short ITS primers, respectively whereas no bands were amplified in A.brassicae. This confirmed the presence of A. candida in asymptomatic inoculated leaves at early stage i.e. 1, 2, 3, 4, 5 and 6 DAI. In light microscopy the presence of pathogen structures were observed from inoculated symptomatic and asymptomatic inoculated leaves. This presence of pathogen structure viz. mycelium and sporangia was observed in asymptomatic leaves at early stage at 6,7,8 and 9 days after inoculation and from symptomatic leaves at 10 and 11 days after inoculation where as no fungal structure in healthy mustard leaves after staining with 1 percent cotton blue in lacto phenol and 0.4% trypan blue. A large number of rapeseed-mustard materials collected from different sources evaluated in field and in glasshouse (at cotyledonary and true leaf stage) revealed that for the confirmation of resistant sources against white rust disease it is very essential to evaluate Brassica materials first in field and then in glasshouse at both the stages i.e. at cotyledonary and true leaf stage under high disease pressure because some Brassica materials escaped from the disease in field but found susceptible in glasshouse at both the stages (EC-399299) or only at true leaf stage ( Katili local, E. sativus, Basanti and Banarasi rai, PWR-14-8, PWR-14-9, PWR-14-10, PWR-14-11, RMT-1-10-1, IC 597942 and IC265495). Among various fungicides Metalaxyl 8% + Mancozeb 64% (Ridomil MZ @ 0.25%) and a biological origin Azoxystrobin (Amistar 25 EC @ 0.1%) were found highly effective in inhibiting sporangial germination in-vitro and were found highly effective in controlling white rust disease (no occurrence of disease) in glasshouse and field in increasing grain yield and test weight followed by Propiconazole, Tebuconazole+Trifloxystrobin, Trifloxystrobin, Kresosim methyl (each at 0.1%). Garlic bulb extracts (2%) was also found effective in managing the disease even better than some old recommended fungicidesThesisItem Open Access Studies on management of Peronospora pisi Syd. the incitant of downy mildew of pea (Pisum sativum L.)(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Pandey, Puja; Kushwaha, K.P.S.ThesisItem Open Access Comparative study of tomato diseases under different growing conditions(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Rautela, Pankaj; Singh, R.P.ThesisItem Open Access Potential of Brassica juncea as biofumigant for the management of damping off in tomato(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Modak, Sourav Kumar; Sharma, RoopaliImposition of ban on the use of methyl bromide by Montreal Protocol (1992) due to its ozone depletion property and increased worldwide concern for the use of ecologically safe, environment friendly methods protecting crops from the plant pathogens has led to the systematic research into alternative strategies for the management of soil borne pests and diseases. Among different alternatives of chemical control methods, biofumigation has gained huge interest. Biofumigation is the practice of growing and incorporating selected Brassica green manure crops which contain biologically active compounds for use in the management of soil borne pests and diseases in various agricultural and horticultural crops. Biofumigation also offers the opportunity to improve soil health through the addition of organic matter and readily available nutrients, which collectively help to achieve sustainable or improved crop production outcomes. In the present investigation an attempt was made to evaluate the potential of Brassica juncea varieties as biofumigant for the management of damping off disease in tomato. Biocidal volatiles released from B. juncea tissue (100 mg powder/plate) degradation of three B. juncea varieties significantly reduced the mycelial growth of Pythium aphanidermatum and other soil borne plant pathogens viz., Rhizoctonia solani, Fusarium oxysporum, Sclerotinia sclerotiorum and Sclerotium rolfsii. Kranti variety was found to be most toxic as it resulted into maximum per cent growth inhibition of all the pathogens over control (P. aphanidermatum; 81.05%, R. solani; 90.41%, F. oxysporum; 92.08%, S. sclerotiorum; 91.66% and S. rolfsii; 92.88%). Incidence of pre and postemergence damping off was found minimum in the treatment Kranti+PBAT-3 in both glasshouse (4.47% pre-emergence and 6.98% post-emergence damping off) and field conditions (11.67% pre-emergence and 5.47% post-emergence damping off). The combination of biofumigation with biocontrol agents also resulted in the increase in the plant growth parameters. The treatment Kranti+PBAT-3 significantly increased germination per cent of tomato i.e. 95.53 per cent in glasshouse and 88.33 per cent in field. The same treatment also resulted in the significant increase in the fresh weight and dry weight of tomato plants. Maximum plant vigour index was also attained in the treatment Kranti+PBAT-3 in glasshouse (4466.03) as well as in field (4034.03). Sinigrin content was found to be maximim in Kranti (21.17 µM/g).ThesisItem Open Access Potential of Raphanus sativus as biofumigant for the management of damping off in tomato(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Negi, Manjari; Sharma, RoopaliThesisItem Open Access Preliminaire studies on thermophilic actinomycetes in relation to the mushrooms and their green mould(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Dhobal, Prerna; Mishra, S.K.ThesisItem Open Access Characterization of elite lines of bread wheat for rust (stripe and leaf) and powdery mildew resistance(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-06) Shivani; Vishunavat, KarunaThesisItem Open Access Pathogenicity and nematicidal activity of plant extracts against root knot nematode, Meloidogyne javanica (Treub, 1885) chitwood, 1949 on moong bean , (Vigna radiata L.) Wilczek(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-06) Joshi, Vijay; Satya KumarThesisItem Open Access Elucidating the role of Trichoderma in the triple combination ‘Copper-Chitosan-Trichoderma’ for the management of late blight disease of potato (Solanum tuberosum L.)(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-06) Bhardwaj, Nitish Rattan; Kumar, J.A ‘triple combination’ comprising of low dose of fungicide (CuOH), biocontrol agent (Trichoderma) and plant defence activator compound (chitosan) developed at Biocontrol laboratory, G.B.P.U.A.&T., Pantnagar and field tested over years was found very effective in the management of late blight of potato. In the present study, the ‘triple combination’ was further investigated by testing its different variants in two geographically different conditions and it was found that the ‘triple combination’ in its various forms was found very effective in managing late blight in both hills as well as plains. Its use led to reduction of disease severity, increased plant growth and increased yield that was at par with the standard recommended fungicides, viz., mancozeb, CuOH used for late blight management. Present study also revealed that spraying of the novel combination at proper concentration (CuOH 500 ppm+CS651 500 ppm+ Tri. (1%)), proper time (5 sprays at 35,45,55,65 and 75 DAS) with proper volume of water (1000 L/ha in 1st spray, 1083 L/ha in 2nd spray, 1166 L/ha in 3rd spray, 1333 L/ha in 4th spray and 1416 L/ha in 5th spray) resulted into significant gains in terms of disease severity reduction, plant growth promotion and tuber yield. Results of in-vitro studies conducted to find out interaction of CuOH-tolerant Trichoderma asperellum strains and chitosan showed that PCR amplification with the primers designed specifically to detect chitosanolytic genes viz., N-acetyl-β-D-glucosaminidase (NAG), hexosaminodase (HEXO) and chitinase (CHIT) resulted in expected bands of ~200bp, ~80bp and ~1450bp in case of NAG, HEXO and CHIT genes, respectively in both CuOH-tolerant Trichoderma asperellum strains TCMS-36 and SBIT-32, which indicated presence of chitosanolytic genes in the two strains. Expression profiling of the chisanolytic genes through real time-PCR revealed that chitosan incorporation into the media led to upregulation of different chitosanolytic genes. In TCMS-36, maximum expression of NAG (6.71±1.20) and HEXO (9.53±0.51) genes was observed at chitosan concentration of 500 ppm, while in case of SBIT32, maximum expression of NAG (2.82±1.45) and HEXO (4.84±1.09) was observed at 125 ppm chitosan concentration. However, in case of CHIT gene, both TCMS-36 and SBIT-32 showed maximum expression (3.29±0.91, 4.32±0.72 respectively) at 125 ppm chitosan concentration. Expression profiling of chitosanolytic genes at protein level through SDS-PAGE revealed the presence of typical band of approximate 93 KDa when these strains were grown in PDB media amended with chitosan (125ppm & 500ppm) and the band was absent when both Trichoderma strains were grown in absence of chitosan, indicating that the production of chitosanase enzyme was substrate specific and that the enzyme corresponded to an exo-type chitosanase (exo-β-Dglucosaminidase). Results of Gas chromatography-mass spectrometry revealed that in addition to efficient chitosanolytic enzymatic battery, these CuOH-tolerant Trichoderma strains also possessed important secondary metabolites such as 1,2-Benzenedicarboxylic acid, 2H-Pyran-2-one, Tri- methylsilyl palmitate, phenolic isomers, etc. that reportedly have antimicrobial and plant growth promotion activity. It is postulated that the CuOH-tolerant Trichoderma asperellum strains used in the triple combination interact with chitosan in a synergistic manner using its chitosanolytic machinery to breakdown chitosan into smaller oligomers that have antimicrobial, plant growth promoting and defence inducing activity. This aspect need to be further addressed in order to understand the mechanism of action of the triple combination in the management of late blight of potato.