DSpace Community: Department of Biology

BIOCONTROL AGAINST INSECT PESTS BY Bacillus thuringiensis ISOLATED FROM ORGANIC AGRICULTURAL FARM

Thu, 12 Oct 2023 00:00:00 GMT

Title: BIOCONTROL AGAINST INSECT PESTS BY Bacillus thuringiensis ISOLATED FROM ORGANIC AGRICULTURAL FARM Authors: Shahee, Chiniya Abstract: Insects are a significant factor in the destruction of agricultural crops. The management must be done in such a way that is free of potentially dangerous chemicals and that remains environmentally benign. Bacillus thuringiensis is a soil bacterium whose main characteristic is the development of parasporal crystalline inclusions that contain the crystal protein which possesses insecticidal effects. The study’s primary objective is to evaluate the insecticidal activity of Bt as a biocontrol agent against insects pests. A total of 60 soil samples were randomly taken from four organic farms in Dharan, Tarahara, Itahari and Jhumka, Nepal. The bacteria were isolated using sodium acetate selection method and were conventionally identified to determine whether the isolates were Bt. Four isolates namely SR1, SI7, ST9 and SJ11 displayed the characteristics of Bt which were bioassayed against two insect pests, Spodoptera frugiperda and Myzus persicae. Bioassay was carried out by preparing crystal/spore mixture (1mg/ml) and feeding it to the insects which were grown in the laboratory by placing them in the disposable plastic glass and directly dipping maize and bean leaves before being given to the appropriate insect. All the four isolates showed insecticidal activity against the insect pest and gave positive result with great potentiality to infect and manage S. frugiperda and M. persicae. The mean difference between treatment and control was statistically significant (p>0.05). The findings showed that the use of living organisms to control pests by implementing bioactive agents or microorganisms that are entomopathogenic to insect pests is an appealing course of action and a sustainable approach for crop protection because they degrade quickly, resulting in fewer exposures and primarily preventing pollution issues brought on by synthetic pesticides. Description: A Thesis Dissertation Submitted to Department of Microbiology Central Campus of Technology, Tribhuvan University, Dharan, Nepal, in Partial Fulfillment of the Requirements for the Award of Degree of Masters of Science in (Agriculture)

EFFECT OF DIFFERENT SUBSTRATES AND THEIR COMBINATION ON THE YEILD OF OYSTER MUSHROOM (PLEUROTUS OSTREATUS)

Sat, 29 Jul 2023 00:00:00 GMT

Title: EFFECT OF DIFFERENT SUBSTRATES AND THEIR COMBINATION ON THE YEILD OF OYSTER MUSHROOM (PLEUROTUS OSTREATUS) Authors: BAJAGAIN, PRAKASH Abstract: Of all the cultivated mushrooms that can grow all year round, Pleurotus has the species that is most developed commercially. They can use a variety of agricultural waste products to transform lignocellulose biomass into delicious, nutritious food. Using agricultural and agricultural waste as a substrate for cultivation of edible mushrooms is an effective and economical technology for turning these waste products into a food that is high in protein and a commercially valuable cash crop. Paddy straw, Wheat husk, and Maize cob were used as substrates in this study for the cultivation of Pleurotus ostreatus mushrooms. The data was analyzed on various aspects such as time required for colonization, time required for pinhead appearance, number of fruiting, and fresh weight of different treatments compared by One-way ANOVA using IBM SPSS Statistics version 29.0.1.0(171) and post hoc multiple comparison was done by Tukeys hsd at 5% level of significance to determine significance differences between the means of mushroom yields. Paddy straw (control) had the quickest colonization time (16.67days) compared to maize cob (20.33 days), but wheat husk (control) had the slowest (31.33 days). The shortest time for primordial formation was in Paddy straw (21.33 days), while the longest in Maize cob (29.67 days) and wheat husk (36.67 days) respectively. Paddy straw had the highest mean fruiting number (619.33), followed by wheat husk (196.67) and maize cob (66.33), respectively. Paddy straw (2519.5gm) was highest in three flushes than Wheat husk (775gm) and Maize cob (775gm) in two flushes. This study also proved that substrates such as wheat husk, maize cob, and paddy straw can be used to grow mushrooms. Description: A Dissertation Submitted to the Department of Microbiology, Central Campus of Technology, Tribhuvan University Dharan, T.U,Nepal In Partial Fulfillment of the Requirements for the Award of Degree of Master of Science in Microbiology (Agriculture)

MULTIDRUG RESISTANCE AND EXTENDED SPECTRUM β-LACTAMASE PRODUCING ESCHERICHIA COLI AND KLEBSIELLA PNEUMONIAE ISOLATES FROM URINE SAMPLES OF PATIENTS ATTENDING A HOSPITAL OF SUNSARI, NEPAL

Tue, 25 Apr 2023 00:00:00 GMT

Title: MULTIDRUG RESISTANCE AND EXTENDED SPECTRUM β-LACTAMASE PRODUCING ESCHERICHIA COLI AND KLEBSIELLA PNEUMONIAE ISOLATES FROM URINE SAMPLES OF PATIENTS ATTENDING A HOSPITAL OF SUNSARI, NEPAL Authors: Karki, Romi Abstract: Multi drug resistant Escherichia coli and Klebsiella pneumoniae expressing extended spectrum β-lactamase enzymes (ESBLs) has become a serious challenges to clinicians for the therapeutic management of clinical cases in urinary tract infection. The main objective of the study was focused to determine the dominance of MDR E.coli and Klebsiella pneumoniae and the evaluation of status of β-lactamase enzyme produced by them. The study was carried out in Apex Hospital, Itahari between June and November, 2019. A total of 350 midstream urine samples were processed among suspected cases of urinary tract infection. The bacteria were isolated by semi quantative culture technique and identified by conventional biochemical tests. The antimicrobial susceptibility testing was performed by modified Kirby Bauer disc diffusion method following Clinical and Laboratory Standards Institute guidelines and were tested for ESBL by combination disc method. The p value <0.05 was considered as statistically significant. A total of 85 samples showed significant bacteriuria with 62 E. coli and 23 Klebsiella pneumoniae. Among the isolates, 62.35% were found MDR strains. By combined disk test, 86.67% E. coli and 13.33% Klebsiella spp. were found ESBL producers. There is significant association between MDR and ESBL production as well as between age group of patients and ESBL producing organisms (P=0.01). Higher prevalence of ESBL producing E. coli and Klebsiella spp. was observed warranting prompt need of surveillance for effective management of such MDR strains. Imipenem, Meropenem and Nitrofurantoin seemed to be drug of choice for UTI. Amoxycillin should no longer considered as drugs for empirical treatment of clinically evident UTI, because of high resistance rates. There is an increasing need for periodic monitoring of drug susceptibility pattern to prevent the spread and development of antimicrobial resistant strains and ESBL producers. Description: A Dissertation Submitted to the Department of Microbiology Central Campus of Technology, Dharan (Constituent Campus of Tribhuvan University) In the Partial Fulfillment of the Requirements for the Award of the Degree of Master of Science in Microbiology (Medical)

INTESTINAL PARASITOSIS AMONG HUMAN IMMUNODEFICIENCY VIRUS AND TUBERCULOSIS INFECTED PATIENTS OF DHARAN, NEPAL

Thu, 01 Dec 2022 00:00:00 GMT

Title: INTESTINAL PARASITOSIS AMONG HUMAN IMMUNODEFICIENCY VIRUS AND TUBERCULOSIS INFECTED PATIENTS OF DHARAN, NEPAL Authors: Rai, Kishor Abstract: Intestinal parasites are those which must have an intestinal life- cycle stage and usually attach in small and large intestine and produces traumatic damage in the intestinal villi. Parasitic infections caused by protozoa and helminths are the most common infections worldwide. The prevalence of parasitic infections varies with the level of sanitation and is highly prevalent among the general population in Nepal<. The presence study was done to find out the prevalence of intestinal parasitosis among HIV and Tuberculosis (TB) patients of Dharan total of 53 sample (<15 years) from HIV seropositive and 28 samples (<20years) from TB patients were collected in a clean, dry and capped fitted container and subjected to macroscopic and microscopic examination for ova, cyst, adult parasites and or segments of parasites. Samples were fixed in 10% formalin-ether solution. Sedimentation technique along with modified acid fast (Zeihl-Neelsen) staining method was performed for opportunistic intestinal parasites in both patients. Multiparasitic infection was noted in the study. The overall prevalence of intestinal parasites was found to be 54(66.67%) among 81 patients (53 HIV patients and 28 TB patients). The parasitosis in male was higher 25(30.86%) than female 15(81.51%). The study preval 18.51% (G. lambia), 14.81% (E. histolytica), 14.81% (Cryptosporidium pavum), 7.40% (Isosporo beli), 4.93% (Microsporodium), 2.46% (Hookworm), 2.46% (Taenia spp.), 1.23% (Blastocystctis homini). In order to prevent this infection appropriate health education should be given to the patients concerning disease transmission, antiparasitic therapy, personal hygiene and safe drinking water. Description: A Desertion Submitted to the Department of Microbiology, Central Campus of Technology, Dharan, T.U, Nepal in Partial Fulfillment of the Requirements for the Award of the Degree of Master of Science in Microbiology (Public Health)