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ThesisItem Open Access PURIFICATION OF CELLULASE AND HEMICELLULASE PRODUCED FROM POTENTIAL MICROBAIL ISOLATES(DR. YASHWNAT SINGH PARMAR UNIVERSITY OF HORTICULTURE AND FORESTRY NAUNI SOLAN, 2012) DOLMA, SONAM; SHARMA, NIVEDIAThesisItem Open Access STUDIES ON PRODUCTION OF ANTIMICROBIAL ACTIVITIES OF BACILLUS SPECIES(DR. YASHWNAT SINGH PARMAR UNIVERSITY OF HORTICULTURE AND FORESTRY NAUNI SOLAN, 2010) THAKURM NAVDEEP; SHRIKOT, C.KThesisItem Open Access ISOLATION AND SCREENING OF POTENTIAL MICROORGANISMS FROM TRADITIONAL FERMENTED FOODS AND TO STUDY THEIR PROBIOTIC ATTRIBUTES(UHF,NAUNI, 2014) SHARMA, RANJANA; SHARMA, NIVEDITAABSTRACT The present investigation was carried out to isolate potential microorganisms from different traditional fermented food sources, their screening, characterization on biochemical as well as molecular level and further more to explore their probiotic potential. Total 22 probiotic isolates were isolated from different food sources of Himachal Pradesh. Most of bacterial isolates were found to be gram positive, catalase negative whereas yeast isolates were found to be coccus in shape and were preli minary screened on the basis of antagonism. Among all, 8 isolates viz. A4, L1, L2, M1, S6, A3, I and Y2 were finally screened and were identified as Lactobacillus sp., Pediococcus acidilactici, Lactobacillus plantarum, Lactobacillus sp., Lactobacillussp., Bacillus licheniformis, Candida sp. and Saccharomyces cerevisiae respectively by 16S and 5.8S ITS rRNA gene technique. These screened probiotic isolates were further evaluated for their probiotic potential viz. acidity tolerance, bile tolerance, antibiotic susceptibility, autoaggregation capacit y, hydrophobicity, bacteriocinogenicity, compatibility and cumulative probiotic potential. All the eight screened probiotic isolates were found to be highly acidity tolerant strains as they showed survival of75.4 to 99.7% at pH 1.0 for 30 to 90 min and were found to be highly sensitive towards all the antibiotics tested, proving them safe for use. These eight screened probiotic isolates showed good autoaggregation capacity i.e. greater that 40% after 5 h and showed strong hydrophobicity towards xylene with hydrophobicity greater than 40%. These screened probiotic isolates showed broad and strong inhibitory spectrum against both gram-positiveand gram-negative pathogenic microorganisms and their growth phase depicted maximum production of inhibitory metabolites in between the late exponential phase and in the beginning of the stationary phase. Screened probiotic isolates supernatant was found to be sensitive to both proteolytic and amylolytic enzymes as decrease in the zone of inhibition was found. Thus, proving that the supernatant must contain proteins or carbohy drate moieties which help in the inhibitory action of these screened probiotic isolates. The entire screened eight isolates were highly qualified the cumulative probiotic score and are being used to prepare probiotic formulated functional foods viz. soy yogurt and fermented ketchup and are successfully accepted in their sensory evaluation. Hence, this study affirms the use of Lactobacillus sp. A4, P. acidilacticiL1, L. plantarumL2, Lactobacillussp. M1, Lactobacillus sp. S6, B. cereus A3, Candida sp. I and Saccharomyces cerevisiaeY2 in the development of new pharmaceutical and functional foods to impart to betterment of the health of public as these eight strains isolated in the present study have been proved safe as well as highly effective probiotics.ThesisItem Open Access CHARACTERIZATION OF PLANT GROWTH PROMOTING RHIZOBACTERIA AND EVALUATION OF THEIR BIOCONTROL POTENTIAL AGAINST TOMATO BACTERIAL WILT(UHF,NAUNI, 2014) SEHGAL, RUTIKA; SHIRKOT, C.K.ABSTRACT Bacteria that colonize plant roots and promote plant growth are referred to as plant growth-promoting rhizobacteria (PGPR). PGPR are highly diverse and in this study we focus on rhizobacteria as biocontrol agents. Their effects can occur via local antagonism to soilborne pathogens or by induction of systemic resistance against pathogens throughout the entire plant. Several substances produced by antagonistic rhizobacteria have been related to pathogen control and indirect promotion of growth in many plants, such as siderophores, lytic enzymes and antibiotics. Induced systemic resistance (ISR) in plants resembles pathogeninduced systemic acquired resistance (SAR) under conditions where the inducing bacteria and the challenging pathogen remain spatially separated. There is a considerable experimental support for the idea that PGPR may be used as biocontrol agent and biofertilizers to increase the yield of tomato crop with concomitant decrease in the chemical fertilizers and pesticides. Therefore, the aim of this study is to screen the antagonistic plant growth promoting rhizobacteria for biocontrol of tomato bacterial wilt with multifarious plant growth promoting traits. The antagonistic bacterial strains were characterized for antagonistic activity along with multifarious plant growth promoting activities like P solubilisation, IAA production, siderophore synthesis, lytic enzyme activity, and ability to fix atmospheric nitrogen under in vitro conditions. Five antagonistic bacterial isolates were tested for biocontrol potential under net house conditions. Isolate CT7A showed maximum reduction of disease incidence. Increase in plant biomass was also observed with the isolate. The isolate was identified as Bacillus subtilis by 16S rDNA sequencing. Therefore, CT7A strain had considerable biocontrol potential as well as growth promotion ability and therefore it could be used as a biocontrol agent against bacterial wilt of tomato.ThesisItem Open Access CHARACTERIZATION OF PLANT GROWTH PROMOTING RHIZOBACTERIA ASSOCIATED WITH MAIZE (Zea maysL.) UNDER LOW HILL CONDITIONS OF HIMACHAL PRADESH(UHF,NAUNI, 2014) DHIMAN, MEENAKSHI; KAUSHAL, RAJESHABSTRACT Plant growth promoting rhizobacteria (PGPR) are used as inoculants for improving the growth and yield of agricultural crops. PGPR are also low cost eco-friendly inoculants for detoxification and bioremediation of soil. The present investigation was carried out during the Kharif seasons of 2013-14 with the objectives to develop a potential bio-inoculum/ bio control agent for maize crop growing in low hill conditions of Himachal Pradesh. The rhizospheric and root samples of maize (Zea mays L.) plants were collected from Hamirpur (31.63˚ N to 76.51˚ E), Bilaspur (31.33˚ N to 76.75˚ E) and Una (31.47˚ N to 76.27˚ E) districts of Himachal Pradesh to isolate an effective inoculums of PGPR with multiple plant growth promoting traits (P-solubilization, N-fixation, IAA, Siderophore, HCN production and antagonism against soil borne pathogens). Five isolates (B1N1, J2, J4, 3M and R6) possesses maximum plant growth promoting traits were selected. On the basis of its morphological, physiological and biochemical characteristics these five isolates were tentatively identified as Bacillus sp. Seed bacterized with isolate B1N1 showed significant increase in germination, leaf number, shoot length,shoot biomass, root length, root biomass over uninoculated control. The seed inoculated withB1N1 registered significant increase in NPK uptake by 78.22, 74.63, 80.77 per cent, respectively over uninoculated control. These two (B1N1 and J2) potential isolates was also identified by 16S rRNA gene sequencing as Bacillus subtilis. Biofertization and bioprotactant potential of selected bacterial isolates paved the way of their use at commercial level to supplement chemical inputs (Fertilizer and fungicide) for enhance production.ThesisItem Open Access COMPARATIVE STUDY OF Pseudomonas aeruginosa, Pseudomonas fluorescens ANDPseudomonas putida ON THE GROWTH OF APPLE IN REPLANT SITE(UHF,NAUNI, 2014) SHARMA, PARUL; KAUR, MOHINDERABSTRACT In the present study, isolation and characterization of fluorescent Pseudomonas sp. from normal and replant site of was done. The twelve Pseudomonasisolates were screened out for various plant growth promoting activities like siderophore, phosphate solubilization, antifungal activity, plant growth regulators (auxins, cytokinins and gibberellins), lytic enzymes and production of HCN and ammonia. On the basis of PGPR activities, two isolates (L and M) were genotypically characterized by 16S rRNA gene sequencing. L showed 95% homology with Pseudomonas putida with accession number (KF751235) and M showed 95% homology with Pseudomonas fluorescenswith accession number (KF751236). These two strains along with another Pseudomonas aeruginosa C strain exploited for the management of replant problem of apple in replant site at Maggota and Sharontha (Shimla). Four different antifungal metabolites were extracted with ethyl acetate were tentatively identified on thin layer chromatography (TLC) at Rf values 0.6, 0.62, 0.82 and 0.8. Antifungal activities of Pseudomonas sp. help in suppression of plant pathogenic fungus in soil and these may be the reasons of better establishment of apple rootstocks treated with fluorescent Pseudomonas strains. These two L, M and one Pseudomonas aeruginosaC strains used in different liquid formulations to treat apple root stocks before plantation in replant site of orchards at Maggota and Sharontha individually and their consortia for treatment of apple rootstocks before planting. The performance of apple plants was much better in terms of root colonization capacity, plant establishment and increase in plant growth in terms of plant height, number of nodes, chlorophyll content of leaves and NPK of rhizosphere soil over their respective control after fifteen months of plantation. These strains can be further exploited for management of replant problem of apple after conducting few more field trials in replant sites and can have great importance in the field of horticulture.ThesisItem Open Access STUDIES ON THE EFFECT OF INOCULATED Pseudomonas STRAINS ON PLANT GROWTH PROMOTING POTENTIAL OF RHIZOSPHERIC SOIL OF APPLE(UHF,NAUNI, 2016) POOJA, DEVI; KAUR, MOHINDERABSTRACT Apple replant disease has plagued apple growers for many years and is now found in most fruit growing regions world-wide. The use of plant growth promoting rhizobacteria (PGPR) for the benefits of agriculture and horticulture is gaining worldwide importance and viewed as a novel and potential tool for providing substantial benefits to the horticulture. In the present study, isolation and characterization of fluorescent Pseudomonas sp. from replanted site of apple orchard (Shimla HP) was done. The eleven Pseudomonas isolates and four already isolated Pseudomonas strains L, M, C and G were screened out for various plant growth promoting activities like siderophore, phosphate solubilization, antifungal activity, plant growth regulators (auxins, cytokinins and gibberellins), lytic enzymes and production of HCN and ammonia. On the basis of PGPR activities, two isolates (ArSh-3 and ArSh-4) were genotypically characterized by 16S rRNA gene sequencing. Already isolated Pseudomonas strains L, M, C and G used in different liquid formulations of individual and consortium fluorescent Pseudomonas to treat apple plants in replanted site of orchards at Sharontha and Siao. The performance of apple plants was much better in terms of root colonization capacity, plant establishment and increase in plant growth in terms of plant height, number of nodes, chlorophyll content of leaves, plant growth promoting activities and NPK of rhizosphere soil over their respective control after twelve months of treatment. These strains can be further exploited for management of replant problem of apple after conducting few more field trials in replanted sites and can have great importance in the field of horticulture.ThesisItem Open Access BIODEGRADATION OF PINE NEEDLES (Pinus roxburghii) WITH MIXED CULTURE UNDER SOLID STATE FERMENTATION(2010) TANDON, DIVYA; SHARMA, NIVEDITAABSTRACT The growing populations, rapid increase in industrialization, moderinization of agricultural, house hold practices as well as transportation have tremendous impact on our environment and this also increased the demand for energy especially for liquid fuel. Various pretreatments of acid and alkali were given to pine needles in order to enhance the rate of biodegradation, among all the pretreatments, NaOH+H2O2 were found to be the best pretreatment. Bioconversion of pine needles into fermentable sugars by employing potential cellulolytic and xylanolytic fungal cultures may be proven as a major step in this direction.Three fungal culture were used for biodegradation and identified as F. oxysporum, P. notatum and A. niger. Sets of three designs were used for biodegradation i.e. single culture, culture consortium and sequential culture for biodegradation of pine needles. Among the three sets, single culture (A.niger) showed maximum biodegradation in terms of enzyme activity, biodegradation index and percent hydrolysis. Biodegradation was apparently increased when tap water was replaced with modified BSM. The enhanced biodegradation of pine needles can be utilized further for bioconversion studies, which is prerequisite for any lignocellulosic waste utilizing biotech industry.ThesisItem Open Access STUDIES ON ANTIFUNGAL ACTIVITIES PRODUCED BY PLANT BENEFICIAL PSEUDOMONAS SPECIES S(2010) RATHORE, ROHIT; KAUR, MOHINDERAbstract Under the present study the aim was to isolate and identify and select native plant beneficial fluorescent Pseudomonas sp. producing antifungal activity from apple and pear growing in normal and replant sites of Chamba district. They all were also screened out for the production of other direct and indirect plant growth promoting activities viz; siderophores, HCN, Ammonia, P-solubilizing, lytic enzymes, in vitro and plant growth regulators viz; auxins, gibberellins, and cytokinins, so as to select potential strains to be further developed and used as inoculants for management of replant problem of apple and pear. Almost all the ten isolates of Pseudomonas sp. showing antifungal activity against Fusarium oxysporum (27.5 to 48.2% growth inhibition), Dematophora sp.(38.4 to 56.9%) and Pythium sp. (33.3 to 53.3%), except two isolates, (AR-4-Cha and AN-2-Cha) did not show inhibitory activity against Pythium sp. All isolates showed production of siderophores (16-20 mm, diameter of yellow zone) and 21.42 to 47.61% siderophore unit), P-solubilizing activity (15 to 23 mm diameter of yellow zone and (27 to 87 μg\ml available orthophosphate) HCN and ammonia (++ to +++++), lytic enzymes proteases (15-21 mm dia of clear zone) and plant growth regulators ie auxins (7-30 μg\ml), gibberellins (21-60 μg\ml) and cytokinins (80-150 μg\ml). Ethyl acetate extracted antifungal metabolites from acidic supernatant of all the isolates of fluorescent Pseudomonas sp. showed inhibition of growth of mycelia of Fusarium oxysporum (46.5 to 55.1%), Dematophora sp. (44.6 to 56.9%) and Pythium sp. (40.0 to 48.3%) on malt extract agar. All the exttact also showed siderophore activity on and in CAS agar and broth in the range of 15 to 22 mm dia. of yellow\orange zone and 8.47 to 28.81%SU. Thin layer chromatographic analysis of extracted antifungal metabolites showed Rf value in the range of 0.68 to 0.76 and development of orange spot after spraying with P-anisaldehyde reagent. Also UV-Visible spectrum of all extract showed maximum absorbance at 270nm. According to literature it was concluded that all the extracted antifungal metabolites may belongs to group of broad spectrum antibiotic i.e. 2,4-diacetylphloroglucinol, which is effective in controlling the soil borne root diseases of plants.