Crop Loss Estimation and Management of Earhead Caterpillar Helicoverpa armigera (Hubner) on Kharif Sorghum
| dc.contributor.advisor | Sekharappa | |
| dc.contributor.author | Kiran Gandhi B. | |
| dc.date.accessioned | 2016-11-10T16:28:08Z | |
| dc.date.available | 2016-11-10T16:28:08Z | |
| dc.date.issued | 2011 | |
| dc.description.abstract | Investigations on crop loss estimation, effect of different dates of sowing and management of sorghum earhead caterpillar, Helicoverpa armigera (Hubner) were undertaken at Main Agricultural Research Station, University of Agricultural Sciences, Dharwad during 2009-10 kharif season. Crop loss estimation studies under natural condition revealed that, CSH-14 recorded least number of larvae (0.33/earhead) and highest grain yield (44.1 q/ha). Whereas minimum per cent earhead damage (1.33%) was recorded on both CSH-14 and CSH-16 cultivars. Overall an extent of 17.42 per cent yield loss can be avoided when protection measures were taken. Under artificial condition as the number of larvae released per earhead increased simultaneously reflected in reduction of grain yield. Low grain yield per earhead was recorded when larvae were released at both stages i.e., flowering and milky stages as compared to larvae released once at each stage. Studies on effect of different dates of sowing indicated that in early date of sowing (12th June 2010) CSH -14 recorded minimum larval load (2 larvae/earhead) and earhead damage (11.33%) with highest grain yield of 39.81 q/ha. Whereas late sowing (24th July 2010) recorded 4.77 larvae/earhead and 43.00 per cent earhead damage with grain yield of 12.90 q/ha. The similar trend was exhibited in CSH-16 under early and late sowing. Among different insecticides tested spinosad 45 SC (0.1 ml/l), novaluran 10 EC (1 ml/l) and azadirachtin 5 per cent (5 ml/l) emerged as superior by recording 72.0, 66.0 and 63.0 per cent population reduction of H. armigera and produced a grain yield of 43.46, 42.23 and 41.16 q/ha, respectively. Maximum gross and net returns were recorded with two sprays of spinosad 45 SC with Rs. 35637.2 and Rs. 22140.2 per ha, respectively. | en_US |
| dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/84957 | |
| dc.publisher | UAS, Dharwad | en_US |
| dc.research.problem | Crop Loss Estimation and Management of Earhead Caterpillar Helicoverpa armigera (Hubner) on Kharif Sorghum | en_US |
| dc.sub | Agricultural Entomology | en_US |
| dc.subject | Agricultural Entomology | en_US |
| dc.theme | Crop Loss Estimation and Management of Earhead Caterpillar Helicoverpa armigera (Hubner) on Kharif Sorghum | en_US |
| dc.title | Crop Loss Estimation and Management of Earhead Caterpillar Helicoverpa armigera (Hubner) on Kharif Sorghum | en_US |
| dc.type | Thesis | en_US |