Loading...
![Thumbnail Image](assets/images/Collection.png)
Theses
Browse
41 results
Search Results
ThesisItem Open Access Impact of physico-chemical properties and microbial dynamics of casing on sporophore development and yield of Calocybe indica P&C(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2009-06) Pandey, Vandana; Mishra, K.K.White milky mushroom (Calocybe indica), is an edible mushroom having white sporophore, large sized fruiting body and delicious flavor. The ability of this mushroom to grow at temperature of about 30-350C, accompanied by its excellent shelf –life makes it highly attractive market venture among the growers. Milky mushroom cultivation involves a number of operations. Once the spawn run is complete, the crop enters into reproductive phase leading to production of fruiting bodies. Even after the colonization of substrate, fructification will not take place unless the colonized substrate is covered with casing layer. Several practical aspects pertaining to casing have also been determined. However, the exact nature of stimulus /stimuli created and imparted leading to sporophore development are not well understood. Investigations carried out all over the world have revealed that the presence and activities of microbial component in the casing layer, is one of the contributing factors. The question, whether the casing micro-flora have a direct effect on the vegetative growth within the casing layer or act indirectly by producing fruiting stimulus or other intrinsic or extrinsic factors, is not clear. Keeping in view the vast potential of microbial dynamics that too in relation to physico-chemical properties of casing, the objectives of present study were undertaken. The spawn of Calocybe indica was prepared on wheat grains using standard methodology. After spawn run, bags were cased with FYM+SC+SS (2:1:1) at different thickness to see the effect of thickness on yield. Different casing mixtures viz. FYM, FYM+SC (1:2), FYM+SC (2:1), SC, SC and FYM+SC+SS (2:1:1) were sterilized, with 4% formalin, autoclaved at 10, 15 and 20 psi and untreated was kept as check, to evaluate their effect on sporophore development and yield of Calocybe indica. These casing mixtures were collected at different time intervals and evaluated for the physico-chemical properties and casing microflora. Out of six casing thickness, 2.5 cm thickness resulted in significantly higher biological efficiency of Calocybe indica (39.4%). However, casing mixture FYM+SC+SS (2:1:1) gave significantly higher yield (368.06g/kg dry substrate). All the casing mixtures treated with 4% formalin resulted in significantly higher yield over other treatment. Among all the casing mixtures, bacterial populations were found to be maximum followed by pseudomonas and fungi and their pattern in different casing mixtures varied. In general, the microbial population increased upto 30 days of casing and thereafter it decreased. The casing mixture FYM+SC+SS (2:1:1) producing maximum yield was having pH 6.31, EC 196.07 deci-simen-1, 2.74% nitrogen, 0.62% phosphorus and 0.60% potassium. The physico-chemical properties (pH, EC, N, P and K) of different casing mixtures showed decline pattern with the advancement of the crop cycle. .ThesisItem Open Access Studies on post harvest diseases of mango: etiology and biological control(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2007-07) Gupta, Sonal; Singh, U.S.India is the largest producer of mangoes and accounts for more than half of the world's production but it ranks third in mango export. Constraints like suitability of few varieties, short storage life, post-harvest pests and diseases etc. restrict the expansion of exports from India. Management of post harvest diseases has been mainly achieved by use of chemicals but due to public's growing health concern and limitation of use of chemicals for export purposes, we have been forced to look for alternative and safe measures for their control. The present work tries to identify the common post harvest diseases, their incidence, severity, varietal susceptibility, management with bioagents, in vitro antagonism studies and effect of bioagents on TSS and TA of fruits. Stem end rot, anthracnose, Rhizopus rot and black mold rot were the four commonly observed diseases. Gulab Khas, Alphonso and Bombay Yellow showed more susceptibility to post harvest while Dushehri, Lucknow Scrfeda and Malihabadi Safeda were relatively less susceptible. Significant in vitro inhibition of Rhizopus species was achieved by Trichoderma spp. and Pseudomonas fluorescens. Yet successful management of these diseases with post harvest fruit dips in bioagent suspensions could not be achieved when fruits were stored at ambient conditions. Langra fruits subjected to high R.H (95%, 30°C) for 12h just after dipping in suspension of biocontrol agents and then stored between 30-35°C, experienced significant reduction in post harvest rotting. In the same treatment significant difference in TSS values was recorded, maximum for P. fluorescens PBAP-28 and minimum for T harzianum PBAT-43. Thus it can be concluded that efficacy of bioagents can be increased under controlled conditions and probably their pre harvest spray will be more effective in managing post harvest diseases as compared to post harvest dips as it can allow their early colonization. In case of post-harvest dip in suspension of Trichoderma and Pseudomonas, storing of the treated fruits for 12 hours at high moisture might help biocontrol agents to multiply and colonize the fruit surface. This will enhance the efficacy of bioagents against post harvest rotting of mangoes. U.ThesisItem Open Access Screening of chemicals, botanicals and bioagents against Fusarium oxysporum, the cause of seed rot of soybean(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2007-07) Mehta, Priyanka; Vishunavat, KarunaSoybean (Glycine max (L.) Merrill), a native of eastern Asia or China is an important pulse crop causing anthracnose, purple stain disease of soybean is one of the cause of lowered seed quality. Assessment of seed quality losses due to purple stain disease, detection of pathogen using different incubation methods, seed transmission and effects of different seed treatments with chemicals, botanicals and bioagents were studied. F. oxysporum was repeatedly isolated from purple stained seeds when subjected to different incubation methods. Czapek‟s Dox Agar medium yielded highest incidence of F. oxysporum followed by blotter method. The germination per cent and vigour index was decreased in infected seeds. These fungi resulted in more abnormal seedlings and seed rot. Germinating seedlings showed chlorosis on cotyledonary leaves followed by necrosis. Bavistin showed good germination per cent, more normal seedling and high vigour index at 500 ppm concentration. Amongst the botanicals, garlic extract reduced the fungal infection and decreased seed rot. However, these botanicals were significantly inferior to all chemical treatment used for seed treatment.ThesisItem Open Access Cultural studies and efficacy of fungicides and botanicals against Colletotrichum gloeosporioides Penz. the causal organism of guava anthracnose(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2007-06) Yadav, Manoj Kumar; Pradeep KumarGuava anthracnose caused by C. gloeosporioides is one of the most important disease of guava. Tarai and Bhabhar region of Uttrakhand and other parts of India. The disease appears on leaves, twigs and fruits and causes sever damage to the fruits during transportation and storage. Keeping in view the seriousness of the disease the present investigation was under taken on cultural character of the test pathogen evaluation of fungicides, botanicals and bio-agent against C. gloeosporioides in- vitro. The pathogen was able to grow in a wide range of synthetic, semi synthetic and natural medium, temperature and pH. Richard‘s medium supported best growth of test pathogen at a temperature of 250C and pH 6.5, respectively. Among the six fungicides evaluated against C. gloeosporioides, Topsin-M, Thiabendazole and Tilt @ 10ppm completely inhibited the growth. In-vitro efficacy of botanicals against the test pathogen, cold water extract of garlic @ 10 per cent was found most effective for complete growth inhibition followed by onion. Amongst the fungal bio-agent tested, Trichoderma viride was found effective inhibiting the growth (42.37per cent) while the bacterial antagonist, Pseudomonas fluorescens was found highly effective as it completely over lapped the growth of test pathogen by 6th day of incubation. The use of botanicals and bio-agent were found cheaper and would be environmentally safer alternative to the fungicides against guava anthracnose and they can explored commercially in Integrated Pest Management stetragy.ThesisItem Open Access Studies on karnal bunt of wheat with particular reference to its management by botanicals and bioagents(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2006-06) Rawat, Laxmi; Singh, K.P.Wheat (Trticum aestivum L.) is one of the primer food crop of the world. It is an important rabi cereal crop of family Poaceae. Wheat is vulnerable to numerous diseases at various growth stages in the field as well as during storage. Among them, the Karnal bunt caused by Neovossia indica (Mitra) Mundkur also referred as ‘New bunt’ or ‘Partial bunt’ was first reported from Karnal, India by Mitra in 1931. The disease affects both the quality and quantity of wheat grains. Wheat lots having 3.0 per cent infected grains are unacceptable for human consumption. The management of the disease is still a challenge to the scientists due to its complex disease-cycle and lack of information about the epidemiology of the disease. Thus, keeping this view and in order to understand the pathogen and disease better, the present investigations were undertaken to evaluate the cultural characters of N. indica insolate UP 262, effect of different pH on teliospore germination, radial growth and sporulation of N. indica, effect of plant extracts on teliospore germination of N. indica and antagonistic effects of soil mocro-organisms against N. indica. A field experment was also conducted during rabi crop season , 2005-06 at Crop Research Centre, G.B. Pant University of Agriculture & Technology, Pantnagar to study the effect of fungicides, botanicals, bioagents and their integration against Karnal bunt of wheat for its management and their effect on yield components by using susceptible wheat cultivar UP 262. The results revealed that out of three media tested, potato dextrose agar medium was found best for growth and sporulation of N. indica isolate. In broth media, glucose yeast extract agar medium supported fairly good growth but least sporulation, whereas potato dextrose broth supported higher sporulation of the isolate. pH 5.5 was found optimum for teliospore germination. No teliospore germination was found below pH 4 or above pH 12. Optimum pH for growth and sporulation was found to be pH 6.0. pH 5.0 gave minimum radial growth and pH 4.0 gave minimum sporulation of N. indica isolate. Botanicals (Neem, Ginger) completely inhibited the teliospore germination of N. indica isolate in standard extract (SE) and 1:10 dilution of SE. Bioagents (T. harzianum, Aspergillus spp, Bacillus spp) inhibited the growth of the test fungus. T. harzianum did not allow N. indica to produce secondary sporida. Hyphac of N. indica interacting with .T. harzianum and Aspergillus spp. showed high vacuolation. Bacillus spp. inhibited the growth of N. indica when it came in contact with it and an inhibition zone was formed between the two. Hyphae of the test fungus showed abnormality as they got shriveled and curved. Seed treatment with Tilt 25 EC @ 1 ml/ kg seed and Castor @ 5 mll/ kg seed produced 938.00 and 935.33 gm plot yield which exhibited 16.52 and 16.08 per cent yield increase over check respectively. Castor @ 5 ml/ kg seed produced maximum no. of grains and weight of grains per ear. T. harzianum @ 4 g/ kg seed + Tilt 25 EC @ 1 ml/ kg seed produced higher length of ear heads followed by Eucalyptus globulus @ 5 ml/ kg seed.ThesisItem Open Access Studies on cultural, biochemical characterization and production technology of Lentinula edodes (Berk.) Pegler(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2006-06) Puri, Smita; Dwivedi, R.R.Lentinula edodes (Berk.) Pegler also known as Shiitake, is a white rot wood decay fungus, that produces flavourful brown sporocarps with medicinal properties. According to a Chinese folkfare, this mushroom is a “elixir of life”, capable of generating stamina, curing colds, improving circulation, lowering blood pressure and prevent premature aging. Many biologically active substances, in particular polysaccharides (Lentinan and lps) have been isolated from L. edodes and a number of products prepared from it, are sold throughout the world as dietary supplements. Many countries have developed production technology of this mushroom but detailed accounts are not available in literature. Therefore, present investigations were undertaken to cultivate, to know its cultural characters along with the biochemical makeup of different strains. The cultural characters of two strains were studied for their radial growth on different media, pH and at different temperatures. Different substrates were used to study the yield performance and biological efficiency of strains. The biochemical makeup of both the strains were studied by estimating total soluble sugars, reducing sugars and non- reducing sugars. The findings indicate that the strains vary extensively in their cultural, morphological and biochemical characteristics along with yielding abilities. Potato dextrose agar medium, temperature 25°C and acidic pH 5.0 were best suited to L. edodes strains. Among the substrates evaluated, wheat straw supplemented with 10 per cent wheat bran gave the maximum yield (80.4 g) and biological efficiency (45.9%) in case of strain L1. The total soluble sugars, reducing sugars and non-reducing sugars contents do not vary significantly in the strains. Total soluble sugars, reducing sugars and non-reducing sugars content are found to be 22.38, 0.03 and 22.35 per cent, respectively, in the fruiting bodies.ThesisItem Open Access Studies on pod and collar rot of soybean caused by Fusarium semitectum (Berk. and Rav.)(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2005-07) Om Prakash; Pradeep KumarPod and collar rot of soybean caused by F. semitectum is one of the most important disease of soybean. The present investigation was undertaken to study the cultural characters of the pathogen, pathogenicity and efficacy of fungicides and bio-agent against the test pathogen in-vitro. Depressed, water soaked, cream coloured lesions were observed on cotyledons and hypoctyles. Later on, these lesions turned dark brown to black. Cultures appear peach coloured from below. Hyphae were septate, macroconidia abundant, microconidia rare. Chlamydospores globose, formed singly or in chains. Among the media tested, Corn meal agar supported best growth and sporulation of the pathogen at 25± 1°C. The pathogen was able to grow at different temperature levels viz., 15 to 40°C optimum being at 25°C. The pathogen was able to grow in a wide range of pH between pH 4.0 to pH 9.0. Poor fungal growth was observed at pH 4.0 and pH 9.0, optimum pH being at 6.5. Culture filtrate of the fungus reduced root length, shoot length and germination percent. Carbendazim was found most effective in inhibiting the radial growth of the pathogen at 40 and 50 ppm followed by Topsin-M while Vitavax was found least effective in checking the growth. Trichoderma harzianum inhibited the growth of F. semitactum by 50 per cent after 6th day and later on, overlapped. Diurnal light fluctuation of 12-12 hours found best for growth and sporulation of pathogen.ThesisItem Open Access Effect of conventional and non-conventional seed treatments on storability of wheat seeds(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2005-06) Chawla, Shilpi; Vishunavat, K.Wheat, Triticum aestivum L. is widely cultivated cereal crop and in terms of production also it is leading among all the food crops in the world. India inspite of being the second largest producer of wheat, deterioration of wheat seeds or grain quality is one of the major constraints for losses by fungi and other pests during storage. In the present investigation Alternaria alternata, Chaetomium globosum, Curvularia lunata, Fusarium moniliforme and Helminthosporium sativum were detected from untreated and pretreated seeds of wheat using Standard Blotter and Agar Plate method. These fungi were found to decrease the percent emergence of normal seedlings and increase the percent emergence of abnormal seedlings and seed rot in wheat seeds during storage from May 2004 to October 2004. Seed treatment with physical heat, chemical fungicides, bioagents and botanicals were given to manage these seed borne fungi during storage. All the treatments were found to be effective and gave significantly higher percent emergence of normal seedlings as compared to check in vivo. However, thiram gave highest percent emergence (83.17 %) of normal seedlings followed by captan (80.3 %) and pinus oil (78.5 %) as compared to check (68.5 %). Under glasshouse conditions, thiram gave highest percent emergence (85 %) of normal seedlings followed by captan (82 %) and pinus oil (79 %) as compared to check (68 %). However, all the treatments used for study were found to be significantly superior over check. Percent inhibition of radial growth of all the five fungi were significantly higher in thiram followed by captan, pinus oil, mustard oil + turmeric powder and Trichoderma harzianum @ 500 ppm as compared to check in vitro. However, all the treatments were significantly superior over check at all the three concentrations. Thiram followed by captan when evaluated under different experiments proved to be the best among conventional seed treatments. However, pinus oil, mustard oil + turmeric powder, solar heat treatment and Trichoderma harzianum were also proved to be the effective treatments among non-conventional seed treatments.ThesisItem Open Access Studies on Colletotrichum falcatum Went., causal agent of red rot of sugarcane with special reference to variability and host resistance(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2005-05) Khulbe, Anjani; Saxena, S.C.Red rot of sugarcane caused by Colletotrichum falcatum Went. is a serious and wide spread disease of sugarcane. Investigations were undertaken to study the variability among the different isolates of fungus causing red-rot of sugarcane.. Observations were recorded in various laboratory and field trials for studying the variability and host resistance against pathogen. The symptoms were observed a withered top, shriveled, wrinkled and reddening of pith with characteristic bands of clean white areas. mid rib of leave is also affected by the fungus, red patches with ash colour develop on the mid rib. Based on the study of the symptoms, the infected plants in the experimental crop area were easily identified and diagnosed having varied degree of infection and severity. Eight different isolates were taken from different sugarcane growing areas to study the growth pattern of the pathogen, Colletotrichum falcatum on different media, different pH, temperature and light conditions. The difference among the eight isolates of C. falcatum was studied in respect of growth and colony characters on oat meal agar. All the isolates showed septate mycelium and conidia were falcate, non-septate and hyaline. Chlamydospores were also formed in most of the isolates. Among the different isolates (K1, K2, K3, K4, 08, 09, B1 and P1) K1 showed fastest growth rate while isolate B1 was slowest. Studying the growth rate in different media Oat meal agar medium was found to be the best for all the isolates. The growth rate of all the isolates was favoured by neutral pH (pH 7) and temperature around 300C in oat meal agar medium. Exposure to different period of light showed no significant difference on the growth rate of the fungus. Of the fifty-six sugarcane genotypes, fifty-one were found to be resistant, four moderately resistant and one showed moderately susceptible reaction in the ratoon crop. in the direct planted sugarcane genotype evaluation trial fifty were found to be resistant, five moderately resistant and one moderately susceptible.