Impact of flowering duration in linseed (Linum usitatissimum L.) resistance to the bud flies (Dasyneura lini Barnes) in Central Uttar Pradesh

A field experiment conducted for screened 288 elite gen pool of linseed against bud fly infestation at Kanpur, India during rabi 2011-12 and 2012-13. The flowering duration showed significant positive relationship (r=0.9278 and 0.9368) with bud infestation. The maximum flowering duration 32.80 and 31.44 days was recorded on variety A-44 with highest bud infestation of 62.29 and 69.99 percent during respective years against variety C-C-1-2 which had a shortest flowering duration of 8.80 and 12.94 days with the minimum 16.38 and 14.30 percent bud fly infestation. Categorization on the basis of flowering duration and damage caused by the bud fly, were found, flowering duration range (11.80- 18.30) and (12.94-21.44), number of entries 11 and 8 were resistant, (0-10 %), flowering duration range (11.80-20.80) and (11.44-25.94), number of entries, 164 and 146 moderately resistant, (10 to 25%), flowering duration range (12.80-30.80) and (11.44- 28.94), number of entries 98 and 116 moderately susceptible, (25 to 50%), flowering duration range (24.80-33.30) and (21.94-32.44), number of entries 15 and 18 susceptible, (50 to 75%), none of the varieties found highly susceptible (more than 75%) to be bud fly attack during 2011-12 and 2012-13, respectively. The variety having longer flowering duration was severely infested by bud fly as compared to those with shorter flowering duration.