Browsing by Author "Mohan, K.S."

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    Baculovirus disease in Oryctes rhinoceros population in Kerala
    (2007-02-08) Mohan, K.S.; Jayapal, S.P.; Pillai, G.B.
    A baculovirus disease was found in Oryctes rhinoceros beetles in Kerala. The symptoms conformed to those reported from South East Asia and the South Pacific Islands. The disease was diagnosed and confirmed by visual symptoms of midgut, smear of midgut contents, immuno-osmophoresis, bioassay in grubs and beetles and electron microscopy of midgut sections of the beetle. The smear test and immuno-osmophoresis were found to be ideal diagnostic methods for routine screening. The bacilliform baculovirus particles measured 215-260x77-108 nm.
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    Biological Control of Pests of Coconut
    (2000) Pillai, G.B.; Antony, J.; Mohan, K.S.; Mariamma Daniel; Devasahayam, S.; Sathiamma, B.; Dangar, T.K.; Ramachandran, C.P.; Abraham, V.A.; Bhat, S.K.; Sreekumar, K.R.; Sukumaran, A.S.; Chandrika Mohan; Murali Gopal; Sosamma, V.K.; Gulsar Banu, J.
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    Biological suppression of coconut rhinoceros beetle Oryctes rhinoceros (L.) in Minicoy, Lakshadweep by Oryctes baculovirus - impact on pest population and damage
    (2007-02-08) Mohan, K.S.; Jayapal, S.P.; Pillai, G.B.
    The population of Oryctes rhinoceros (L.), one of the key pests of coconut palm, has been substantially reduced in Minicoy Island, Lakshadweep, through the use of a virus disease of the pest. O. rhinoceros beetles were infected with Oryctes baculovirusLD50 dose/ml, of inoculum) and released into the pest population in Minicoy Island in April, 1983. The virus was previously isolated from field-collected, diseased O. rhinoceros beetles from Kayangulam in Alleppey District, Kerala.- Pre-release observations at Minicoy in April, 1983 revealed high incidence of pest damage to coconut and the absence of the viral disease in the pest population. Post-release observations recorded after two years revealed spread of the virus disease to the subsequent generations of beetles and larvae in breeding sites. The resultant epizootic in the pest population drastically reduced the larval population in breeding sites, leading to a substantial reduction in the damage to coconut palms in experimental plots.
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    Diagnosis of baculovirus infection in coconut rhinoceros beetles by examination of excreta
    (2007-02-08) Mohan, K.S.; Jayapal, S.P.; Pillai, G.B.
    Oryctes rhinoceros beetles, when infected with Oryctes baculovirus, excreted gut epithelial cells having hypertrophied nuclei, between the third and ninth day post-inoculation. Detection of such abnormal nuclei in the excreta was used as a method of diagnosis of baculovirus infection in field-collected beetles, needed alive for various experiments. This method eliminates the need for sacrificing the beetles for mid-gut examination, a routine method of diagnosis.
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    Diagnosis of baculovirus infection in coconut rhinoceros beetles by examination of excreta
    (1986) Mohan, K.S.; Jayapal, S.P.; Pillai, G.B.
    Oryctes rhinoceros beetles, when infected with Oryctes baculovirus, excreted gut epithelial cells having hypertrophied nuclei, between the third and ninth day post-inoculation. Detection of such abnormal nuclei in the excreta was used as a method of diagnosis of baculovirus infection in field-collected beetles, needed alive for various experiments. This method eliminates the need for sacrificing the beetles for mid-gut examination, a routine method of diagnosis.
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    Response of Oryctes Rhinoceros Larvae to Infection by Oryctes Baculovirus.
    (1985) Mohan, K.S.; Jayapal, S.P.; Pillai, G.B.
    Three larval instars of Oryctes rhinoceros (L.) were infected with Oryctes baculovirus through contaminated feed. The primary external pathological symptom was translucency of the thorax. Internally, the midgut contained turbid fluid with flakes of sloughed-off epithelial tissue. Baculovirus infection in larvae could be diagnosed in Giemsa stained scrappings of the midgut epithelium, two days after inoculation, whereas bioassay test could detect infection on the third day. Median lethal dose (LD50) and weight of infected tissue containing one LD50 dose for all the three instars were computed. The second instar was the least susceptible to virus infection. The order of susceptibility among the instars was 1>III>II. Translucency was found to appear 3-4 days prior to death. Lethal infection period ranged from eleven to sixteen days. The thermal inactivation point of the virus in tissue suspension was at 56C.
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