MPhil Thesis
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Item Effects of Agro Chemicals on Live Fishes(University of Rajshahi, 1995-06) Yasmin, Khaleda; Hossain, M. AltafThe effect of three organophosphorous insecticides, namely, diazinon 60 E.C., nogos 100 E.C. and dimecron 100 SCW on H. fossilis and three species of live A. testudineus, C. batrachus, were studied. The insecticides were in the form of emulsifiable concentrates. In bioassays the or toxicity tests, fishes were exposed to a series of concentrations of chemicals at the laboratory temperature. The dosages were 1.0, 2.25, 3.2, 5.6 and 10.0 ppm. Histopathological effects of these three insecticides on the same species were observed. The dosages were 2.25, 3.50, 5.0. 10.0 and 20.0 ppm respectively. The histopathology of the organs of normal fishes were done to compare them with those of the experimental ones. These insecticides induced certain cellular changes in different organs such as liver intestine, ovary etc. on these fishes. From the bioassay tests and histopathological studies, it was observed that diazinon was most toxic, nogos was moderately toxic and dimecron was least toxic to these fishes among the three insecticides.Item Studies on The Optimum Population Density of Carps Fry In Nursery Ponds(1990) Afroze., Shelina; Hossain, M. AltafThe present work is on the optimum population density of three major carps fry viz. Labeo rohita,Catla catla and Cirrhina rigal in nursery ponds and tanks. A comperative study has been carried out on the growth rate of the fish fry on an exact time after releasing them in different nursery ponds and tanks at different ratios. Chapter I: Growth effeC!-l.-2rative study on Ehic.2..= chemical factor and morphometric relati,£!:!sh1J22!ith different density. The total length/standard length and total length/ body depth relationships hae been calculated in the linear regression equation for the three species of carp fry reared in tanks and ponds for initial and final measurements. It may be observed that SL and ED always depend upon TL ofthe species and positively correlated and the values were significant in all the cases. ------Item Morpho-Histology of Gut and Microbiological Study on Gut Content of Earthworms of Rajshahi University Campus(University of Rajshahi, 2009) Haque, Md. Fazlul; Saha, Ananda KumarEarthworm plays an important role on economy and society of Bangladesh which is based on agriculture. A fertile and productive soil is the fundamental resource for sustainable Agriculture. Earthworm can play a variety of important roles in fertility and productivity of soil by providing shelter to the beneficial microbes in their gut and by activating soil microbial activity through the excretion and casting. Many microorganisms in the soil remain in the dormant stage, awaiting suitable habitat for the vigorous multiplication. Earthworm gut is suitable habitat for many microorganisms, but not for all. Many microorganisms may be digested in gut. Therefore, present investigation was done to find out the morpho-histological and microbiological variation in gut of different earthworm species. Then, investigation was done to ascertain the correlation between morpho-histological variation and microbial variation of gut of different earthworm species. Rajshahi University campus was the study area of the present research work. Three types of habituates i.e., shady land, crop land and drainage of residential hall were selected for study from September, 2004 to August, 2005. The fortnightly sampling dates were fixed on 14th day for first sampling and 28th day for 2nd sampling each month. Quadrate sampling and Hand sorting methods were used to collect earthworm. Collected earthworms were identified with an identification key. Data on weather were collected from Regional Weather Office of Rajshahi. For morphological study, earthworms were dissected and cleaned to separate the gut. Permanent slides of gizzard, stomach and intestine of the gut were prepared and then observed by advanced biological microscope for histological study. Bacterial load of gut of earthworm was studied by serial dilution method and spread plate technique on nutrient agar plate. Finally, pure culture of bacteria isolated from the different parts of gut of earthworms were tested for Gram character, morphology, motility, catalase and oxidase reactions, citrate utilization and coagulase test. The isolates were then identified with Bergey's manual of systematic bacteriology. Six species of earthworm i.e., Metaphire posthuma, Eutyphoeus orientalist, Eutyphoeus Nicholson, Eutyphoeus incommodious, Lampito Mauritia and Drawida lime/la were identified from three studied habitats. Earthworm diversity was present in the studied habitats. The number of earthworms also varied with month. In most cases, higher number of earthworms was recorded on July, August and September. On the other hand, lower number of earthworms was recorded from November to April. Morphological study of gut of earthworm revealed that number, length and position of different parts of gut of all studied earthworm species were not same. Result of histological study showed that same layers of muscle and cuticle were presence in gut of all studied species of earthworm, but some species ways variation were found in the width of the different layers of the gut. Result of bacterial load study showed that bacterial load of gut varies with part of the gut, species of earthworm and season or month of the year. But species ways variation of bacterial load was not statistically significant. Analysis of correlation indicates that bacterial load of one part gut is correlated with that of other parts of gut and also with the components of weather. The highest bacterial load of gizzard was recorded in D. lime/la on September while the lowest load was recorded in E. Nicholson on January. Bacterial load of stomach of E. oriental it was higher than that of the other species from January to May, but that of E. Nicholson was higher than that of the other species from June to December. Bacterial load of stomach of D. lime/la was lower than that of the other species from December to July. But miscellaneous result was found on lower bacterial load from August to November. The highest bacterial load of intestine was recorded in E. Nicholson on September while the lowest load was recorded in E. incommodious on December. Five genera of bacteria were identified from six species of earthworm. These were Bacillus, Pseudomonas, Klebsiella, Streptococcus and Acinetobacter. No remarkable variation of bacterial fauna was found in studied species of earthworm. In other ward, these five types of bacteria were found in all studied species of earthworm. It can be concluded that there is morpho-histological variation in gut of different earthworm species. But morphological variation was more prominent than the histological variation of gut of earthworm. One other hand, insignificant species ways variation of bacterial load and uniform types of gut bacteria reveal that there is no species-specific bacterial profile for gut of different earthworm. Therefore, form the data of this study it is not possible to establish a method for identification of an earthworm species depending on their bacterial profile of gut.Item An Estimate of Cytoplasmic Incompatibility and its Use in the Control of a Storage Pest, Tribolium castaneum (Herbst)(University of Rajshahi, 2000) Hoque, Kazi Md. Faisal; Islam, M. SaifulUsing purebred and hybrid crosses involving four indigenous (viz. CHI, DHA, KHU and RAJ) and four exotic (viz. BLA, CTC, FSS and KAN) strains of the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera:Tenebrionidae), cytoplasmic incompatibility (Cl) relationships between the strains have been established. An analysis of the observed incompatibility, where the percentage of egg-hatch data was considered as· an index, demonstrate that of 52 crosses, 34 (65.38%) were compatible, 12 (23.08%) were partially incompatible and 6 ( 11.54%) were incompatible. The results suggest that two of the indigettous strains viz. KHU and RAJ and three of the exotic strains viz. CTC, FSS and KAN might be infected with RMO (rickettsia-like microorganisms). Backcross data, on the other hand, indicate th:at the two indigenous (KHU and RAJ) and one exotic (BLA) strains clre perhaps uninfected. Effect of tetracycline treatment in the food medium and its consequence on the expression of Cl in T. castaneum demonstrate that when males reared on untreated· food are mated with the females reared on a similar medium, all the infected strains show compatibility. But when untreated males are paired with females reared on tetracycline-treated food, all the crosses exhibit incompatibility. Alternatively, when males reared on treated medium are crossed to females reared either on untreated or treated medium, all the cross-matings become compatible. This indicated that the tetracycline treatment might have 'cured' the infected males from the RMO, if any. Apparently fecundity of the experimental insects was not affected by the tetracycline treatment.Item Biology and Ecology of Predaceous Coccinellids with Special Reference to their Incidence In Response to Aphid Population and Temperature(University of Rajshahi, 1984) Rahman, A.S.M.Shafiqur; Quayum, M.A.The biology of an insect is an important factor to be studied tor obtaining a knowledge on the nature and extent of damage to a particular crop. Thus, the biology of predaceous coccinellids have been undertaken for investigation with a view to finding out of its economic importance as well as to comparing their efficiency with other predaceous insects. Our knowled on the biology of these predaceous insects is very scanty in our country. However, Hagen (1962) and Hodek (1967) studied the biology of some predaceous coccinellids in California and Czechoslovakia respectively. Savoiskaya (1974) studied the biology and morphology of coccinellid beetles and gave an estimated economic value in the process of biological control of insect pests. Islam and Nasiruddin (1978) studied· the life-histories of Q. repanda and Q. septempunctata. in Bangladesh. Abraham il - (1976) studied thelbiology of c. arcuata, a predator of the rice pest, Nilaparvata lugens in India. Besides those some biological works have been conducted on Q. undecimpunctata aegyptiaca Reiche. ( Kamal, 1951; Ibrahim, 1955), on A• bipunctata L. (Nielson and Curri, 1960; Butler and Dickerson, 1972 ) , on Diloponis inconspicuus Pope (Brettell,1964)