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Phytopathogenic Mollicutes
The Pharma Innovation Journal, 2021
Arecanut (Areca catechu L.) is an important cash crop in the Eastern Ghats, Western Ghats, East a... more Arecanut (Areca catechu L.) is an important cash crop in the Eastern Ghats, Western Ghats, East and North Eastern regions of India. Karnataka is the leading producer of arecanut in India accounting for more than half of the area grown in the country. The farmers of Malnad, Coastal and Maidan areas are facing lot of difficulties in arecanut production as the crop is severely affected by various biotic and abiotic stresses which causes a drastic reduction in yield. In order to know the occurrence of various diseases an intensive roving survey was carried out during kharif and rabi 2018-19, 2019-20 and 2020-21 in arecanut growing taluks of Shivamogga district in Karnataka. The results revealed the prevelance of all most all the diseases in arecanut expect yellow leaf disease.
Different cow pea varieties viz., C-152, KBC-2, KBC-1, KM-5, IT-38956, TVX-944 and CP-17were test... more Different cow pea varieties viz., C-152, KBC-2, KBC-1, KM-5, IT-38956, TVX-944 and CP-17were tested for their susceptibility to Callosobruchus maculatus and C. analis at Department of Entomology. Agricultural College, Shimoga. Among them, CP-17 was comparatively less preferred host with lesser oviposition (81.33 eggs /100 g seeds), prolonged developmental period (34.67 days), least adult survival (84.67 %) and weight loss of grains (0.96%) followed by IT-38956 to C. maculatus. Similar trend in case of C. analis was observed with lesser oviposition (65.33 eggs / 100g seeds), prolonged developmental period (36.83 days), least adult survival (59.33%) and grain weight loss (0.90%) on CP-17 when compared with local variety. C-152 and local variety was recorded most preferred host for both the species.
Journal of Pharmacognosy and Phytochemistry, 2017
Onion (Allium cepa L.) is one of the oldest known and an important vegetable crop grown in India.... more Onion (Allium cepa L.) is one of the oldest known and an important vegetable crop grown in India. Productivity of onion is affected by many biotic and abiotic stresses. Among the biotic stresses diseases play an important role and among them, purple blotch caused by Alternaria porri is one of the most destructive disease. The study was conducted to check the efficacy of different fungicides and bio-agents under field condition. The results revealed that among the chemicals Difenconazole 25 EC (Score) @ 0.1 % was found effective in reducing the disease with a per cent disease reduction over control of (62.23) was onpar with (Tebuconazole + Trifloxystrobin) @ 0.05 % (60.51). Among the bio-agents tested Trichoderma harzianum was found effective with the per cent disease reduction over control of (54.47) followed by treatment with a combination of Trichoderma harzianum and Pseudomonas flouroscens (41.91).
The version presented here may differ from the published version. If citing, you are advised to c... more The version presented here may differ from the published version. If citing, you are advised to consult the published version for pagination, volume/issue and date of publication
Journal of Pharmacognosy and Phytochemistry, 2018
Xanthomonas campestris pv. arecae is an important and destructive pathogen causing bacterial leaf... more Xanthomonas campestris pv. arecae is an important and destructive pathogen causing bacterial leaf stripe in arecanut. Attempt were made to ascertain the variability in Xanthomonas campestris pv. arecae. The tests conducted to know the biochemical properties of the pathogen. Hence, pathogen was subjected to various biochemical tests, the results indicated that, ammonia production, starch hydrolysis, fluorescent test and gram staining showed negative reaction whereas, positive reaction were observed in catalase test, liquefaction of gelatin, KOH test, methyl red test and hydrogen sulphide production.
Scarlet miteRaoiella indicaHirst (Acari: Tenuipalpidae) is an important sucking pest on young are... more Scarlet miteRaoiella indicaHirst (Acari: Tenuipalpidae) is an important sucking pest on young arecanut palms during dry weather in areca growing tracts. The registered insecticides that pro vide adequate control of the pests need repeated application in higher doses which result in adverse effects on environment and health. In order to circumvent the problems, replacement of conventional insecticides with new powerful molecules at lower dose is necessary. Hence a replicated field experiment was conducted at five different locations for two consecutive years (2008 -09 and 2009-10). Two sprays each of the new molecules fenazaquin 10EC 1.5ml/l, diafenthiuran 50WP 1.2gm/l and propargite 57EC 0.5ml/ l were compared with wettable sulphur 80% WDG 2.5gm/l, dicofol 20EC 2.5ml/l, Azadirachtin1300 ppm 0.03% 3ml/l and untreated control. Pooled results showed that five days after spray, all the treatments recorded significantly less number of mites (pe r cm 2 leaf)as against control. Propargite ...
Black pepper (Piper nigrum L.), the king of spices is one of the most important spice crops culti... more Black pepper (Piper nigrum L.), the king of spices is one of the most important spice crops cultivated in India. The cultivation and production of black pepper is limited by many diseases of which foot rot caused by Phytophthora capsici is the most important and serious disease. All parts of the plant are susceptible and prone to the infection at any stage of the crop creating huge losses of around 25-30%. An attempt was made to study the effect of different culture media, fungicides and bio control agents on the growth of the pathogen in vitro.
Studies was carried out to investigate population dynamics and the impact of abiotic factors on p... more Studies was carried out to investigate population dynamics and the impact of abiotic factors on population dynamics of sucking insect pests of transgenic cotton viz., leafhopper (Amrasca biguttula biguttula Ishida), aphid (Aphis gossypii Glover), whitefly (Bemisia tabaci Gennadius) and thrips (Thrips tabaci Linnman), under unprotected condition. The results of the field study revealed that the sucking pest population was found throughout the year except in July and August months. The peak population of leafhopper, aphid, whitefly and thrips were 19.20, 45.07, 29.50 and 26.81 per three leaves during May second fortnight for leafhopper and aphid, April second fortnight for whitefly thrips, respectively. Simple correlation analysis revealed that maximum temperature showed significant positive effect on all the sucking pests. The minimum temperature showed negative effect on aphid population and non significant effect on leafhopper, whitefly and thrips population. The relative humidity ...
The native strains of entomopathogenic nematode (EPNs) were evaluated against arecanut white grub... more The native strains of entomopathogenic nematode (EPNs) were evaluated against arecanut white grub, Leucopholis lepidophora Blanchard during 2015 -17 at two locations viz., Koluru (Thirtahalli taluk) and Harakere (Shivamogga taluk) villages of Shivamogga district of Karnataka, India. Field trials were conducted under All India Coordinated Research Project (AICRP) on Palms to identify the suitable eco friendly management measures. The imposition of aqua formulation of EPN, Steinernema carpocapsae (CPCRI-SC1) @ 60 lakh IJs/palm during June July followed by combined application with insecticide imidacloprid 17.8 SL @ 0.0045% during September October was caused 96.6% and 92.5% reduction in grub population in farmers field at Koluru and Harakere village respectively over pretreatment grub population followed by EPN alone application of S. carpocapsae caused 74.3% and 79.1% and talc formulation of H. indica caused 54.8% and 51.7% reduction in grub population in the respective villages. The...
Fungicides applied for the management of plant diseases have a toxic effect on the biological con... more Fungicides applied for the management of plant diseases have a toxic effect on the biological control agents. For effective disease management, the activity of biological control agents should not be hampered by the application of fungicides. To find the compatibility of bioagents with the fungicides, we have evaluated the different fungicides against Trichoderma asperellum in vitro. Among contact fungicides, Trichoderma was compatible with copper hydroxide, copper oxychloride and mancozeb, and least compatible with captan. Whereas among systemic fungicides, metalaxyl was compatible at all the concentrations whereas tebuconazole, propiconazole and carbendazim were incompatible. Among combination fungicides, metalaxyl-M + mancozeb was found to be highly compatible whereas other combination fungicides tested were incompatible with Trichoderma.
International Journal of Current Microbiology and Applied Sciences
Phytopathogenic Mollicutes
The Pharma Innovation Journal, 2021
Arecanut (Areca catechu L.) is an important cash crop in the Eastern Ghats, Western Ghats, East a... more Arecanut (Areca catechu L.) is an important cash crop in the Eastern Ghats, Western Ghats, East and North Eastern regions of India. Karnataka is the leading producer of arecanut in India accounting for more than half of the area grown in the country. The farmers of Malnad, Coastal and Maidan areas are facing lot of difficulties in arecanut production as the crop is severely affected by various biotic and abiotic stresses which causes a drastic reduction in yield. In order to know the occurrence of various diseases an intensive roving survey was carried out during kharif and rabi 2018-19, 2019-20 and 2020-21 in arecanut growing taluks of Shivamogga district in Karnataka. The results revealed the prevelance of all most all the diseases in arecanut expect yellow leaf disease.
Different cow pea varieties viz., C-152, KBC-2, KBC-1, KM-5, IT-38956, TVX-944 and CP-17were test... more Different cow pea varieties viz., C-152, KBC-2, KBC-1, KM-5, IT-38956, TVX-944 and CP-17were tested for their susceptibility to Callosobruchus maculatus and C. analis at Department of Entomology. Agricultural College, Shimoga. Among them, CP-17 was comparatively less preferred host with lesser oviposition (81.33 eggs /100 g seeds), prolonged developmental period (34.67 days), least adult survival (84.67 %) and weight loss of grains (0.96%) followed by IT-38956 to C. maculatus. Similar trend in case of C. analis was observed with lesser oviposition (65.33 eggs / 100g seeds), prolonged developmental period (36.83 days), least adult survival (59.33%) and grain weight loss (0.90%) on CP-17 when compared with local variety. C-152 and local variety was recorded most preferred host for both the species.
Journal of Pharmacognosy and Phytochemistry, 2017
Onion (Allium cepa L.) is one of the oldest known and an important vegetable crop grown in India.... more Onion (Allium cepa L.) is one of the oldest known and an important vegetable crop grown in India. Productivity of onion is affected by many biotic and abiotic stresses. Among the biotic stresses diseases play an important role and among them, purple blotch caused by Alternaria porri is one of the most destructive disease. The study was conducted to check the efficacy of different fungicides and bio-agents under field condition. The results revealed that among the chemicals Difenconazole 25 EC (Score) @ 0.1 % was found effective in reducing the disease with a per cent disease reduction over control of (62.23) was onpar with (Tebuconazole + Trifloxystrobin) @ 0.05 % (60.51). Among the bio-agents tested Trichoderma harzianum was found effective with the per cent disease reduction over control of (54.47) followed by treatment with a combination of Trichoderma harzianum and Pseudomonas flouroscens (41.91).
The version presented here may differ from the published version. If citing, you are advised to c... more The version presented here may differ from the published version. If citing, you are advised to consult the published version for pagination, volume/issue and date of publication
Journal of Pharmacognosy and Phytochemistry, 2018
Xanthomonas campestris pv. arecae is an important and destructive pathogen causing bacterial leaf... more Xanthomonas campestris pv. arecae is an important and destructive pathogen causing bacterial leaf stripe in arecanut. Attempt were made to ascertain the variability in Xanthomonas campestris pv. arecae. The tests conducted to know the biochemical properties of the pathogen. Hence, pathogen was subjected to various biochemical tests, the results indicated that, ammonia production, starch hydrolysis, fluorescent test and gram staining showed negative reaction whereas, positive reaction were observed in catalase test, liquefaction of gelatin, KOH test, methyl red test and hydrogen sulphide production.
Scarlet miteRaoiella indicaHirst (Acari: Tenuipalpidae) is an important sucking pest on young are... more Scarlet miteRaoiella indicaHirst (Acari: Tenuipalpidae) is an important sucking pest on young arecanut palms during dry weather in areca growing tracts. The registered insecticides that pro vide adequate control of the pests need repeated application in higher doses which result in adverse effects on environment and health. In order to circumvent the problems, replacement of conventional insecticides with new powerful molecules at lower dose is necessary. Hence a replicated field experiment was conducted at five different locations for two consecutive years (2008 -09 and 2009-10). Two sprays each of the new molecules fenazaquin 10EC 1.5ml/l, diafenthiuran 50WP 1.2gm/l and propargite 57EC 0.5ml/ l were compared with wettable sulphur 80% WDG 2.5gm/l, dicofol 20EC 2.5ml/l, Azadirachtin1300 ppm 0.03% 3ml/l and untreated control. Pooled results showed that five days after spray, all the treatments recorded significantly less number of mites (pe r cm 2 leaf)as against control. Propargite ...
Black pepper (Piper nigrum L.), the king of spices is one of the most important spice crops culti... more Black pepper (Piper nigrum L.), the king of spices is one of the most important spice crops cultivated in India. The cultivation and production of black pepper is limited by many diseases of which foot rot caused by Phytophthora capsici is the most important and serious disease. All parts of the plant are susceptible and prone to the infection at any stage of the crop creating huge losses of around 25-30%. An attempt was made to study the effect of different culture media, fungicides and bio control agents on the growth of the pathogen in vitro.
Studies was carried out to investigate population dynamics and the impact of abiotic factors on p... more Studies was carried out to investigate population dynamics and the impact of abiotic factors on population dynamics of sucking insect pests of transgenic cotton viz., leafhopper (Amrasca biguttula biguttula Ishida), aphid (Aphis gossypii Glover), whitefly (Bemisia tabaci Gennadius) and thrips (Thrips tabaci Linnman), under unprotected condition. The results of the field study revealed that the sucking pest population was found throughout the year except in July and August months. The peak population of leafhopper, aphid, whitefly and thrips were 19.20, 45.07, 29.50 and 26.81 per three leaves during May second fortnight for leafhopper and aphid, April second fortnight for whitefly thrips, respectively. Simple correlation analysis revealed that maximum temperature showed significant positive effect on all the sucking pests. The minimum temperature showed negative effect on aphid population and non significant effect on leafhopper, whitefly and thrips population. The relative humidity ...
The native strains of entomopathogenic nematode (EPNs) were evaluated against arecanut white grub... more The native strains of entomopathogenic nematode (EPNs) were evaluated against arecanut white grub, Leucopholis lepidophora Blanchard during 2015 -17 at two locations viz., Koluru (Thirtahalli taluk) and Harakere (Shivamogga taluk) villages of Shivamogga district of Karnataka, India. Field trials were conducted under All India Coordinated Research Project (AICRP) on Palms to identify the suitable eco friendly management measures. The imposition of aqua formulation of EPN, Steinernema carpocapsae (CPCRI-SC1) @ 60 lakh IJs/palm during June July followed by combined application with insecticide imidacloprid 17.8 SL @ 0.0045% during September October was caused 96.6% and 92.5% reduction in grub population in farmers field at Koluru and Harakere village respectively over pretreatment grub population followed by EPN alone application of S. carpocapsae caused 74.3% and 79.1% and talc formulation of H. indica caused 54.8% and 51.7% reduction in grub population in the respective villages. The...
Fungicides applied for the management of plant diseases have a toxic effect on the biological con... more Fungicides applied for the management of plant diseases have a toxic effect on the biological control agents. For effective disease management, the activity of biological control agents should not be hampered by the application of fungicides. To find the compatibility of bioagents with the fungicides, we have evaluated the different fungicides against Trichoderma asperellum in vitro. Among contact fungicides, Trichoderma was compatible with copper hydroxide, copper oxychloride and mancozeb, and least compatible with captan. Whereas among systemic fungicides, metalaxyl was compatible at all the concentrations whereas tebuconazole, propiconazole and carbendazim were incompatible. Among combination fungicides, metalaxyl-M + mancozeb was found to be highly compatible whereas other combination fungicides tested were incompatible with Trichoderma.
International Journal of Current Microbiology and Applied Sciences