Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract Full Text

Population dynamics of major insect pests of linseed (Linum usitatisimum Linn.) and assessment of seed yield losses caused by them.

Abstract

The maximum incidence of leaf miner was recorded in 3rd standard week of February under both protected and non-protected treatments during both years. However, protected treatment resulted significantly lower incidence of leaf miner as compared to non-protected treatment at all stages during both years. Variety 'ND:-2002' in 2005-06 and 'Garima' in 2006-07 recorded the lowest incidence of leaf miner, however, maximum incidence was recorded with variety 'Neelum' during both years. A period from 3rd standard week to 9th standard week was found to be the most favourable period for higher incidence of linseed budfly under both protected and non-protected treatment during both years. Variety 'Garima' recorded the minimum incidence of budfly during both years. However, maximum incidence of budfly was recorded in variety 'Neelum' during both years. The incidence of semilooper was started from 4th standard week and reached to a maximum level in 8th standard week (0.444 and 0.478) in protected and (1.111 and 1.011) in non-protected treatment in respective years. The incidence of gram pod borer started from 6th standard week and reached maximum at 9th standard week during both years. Protected treatment resulted in significantly the lowest incidence of gram pod borer as compared to non-protected treatment during both years. Protection of insect-pests infestation by Endosulphan 35EC @ 0.07% was found effective under different genotypes of linseed. The per cent increase in grain yield by protected treatment was 24.18 in 2005-06 and 27.86 in 2006-07 as compared to non-protected treatment. The variety 'Neelum' resulted in maximum grain yield of 18.70 q/ha followed by 'NDL 2003-4 (18.60 q/ha), 'NDL 2002 (18.30 q/ha), 'Garima' (14.10 q/ha), 'Janki' (13.20 q/ha) and 'Padmini' (9.30 q/ha) under protected treatment, and variety 'NDL 2003-4' (12.90 q/ha) followed by 'NDL 2002' (11.60 q/ha) 'Garima' (11.50 q/ha), 'Janki' (11.50 q/ha), 'Neelum' (11.30 q/ha) and 'Padmini' (8.70 q/ha) under non-protected treatment. On the basis of mean of protected and non-protected treatment, the varieties followed the order as 'NDL-2003-4' > 'NDL 2002' > 'Neelum' > 'Garima' > 'Janki' and 'Padmini'.