﻿144 
  

  

  PEOCECDINGS 
  OF 
  THE 
  FOrRTII 
  ExVTOi[OLOGICAL 
  MEETING 
  

  

  to 
  three 
  weeks 
  later. 
  At 
  these 
  two 
  occasions 
  if 
  all 
  affected 
  plants 
  with 
  

   dead-hearts 
  are 
  uprooted 
  and 
  burnt 
  and 
  wherever 
  it 
  is 
  found 
  that 
  in 
  

   doing 
  so 
  the 
  rows 
  become 
  very 
  gappy 
  then, 
  the 
  shoots 
  with 
  dead-heart 
  

   are 
  cut 
  back 
  to 
  the 
  ground 
  level 
  and 
  allowing 
  the 
  side 
  shoots 
  to 
  grow 
  

   up, 
  the 
  pest 
  is 
  very 
  easily 
  controlled 
  at 
  a 
  very 
  low 
  extra 
  cost 
  and 
  its 
  

   further 
  spread 
  is 
  too 
  much 
  checked. 
  During 
  the 
  last 
  monsoon 
  this 
  

   was 
  being 
  practised 
  at 
  Surat 
  Government 
  Farm. 
  At 
  that 
  time 
  the 
  

   percentage 
  of 
  attack 
  varied 
  from 
  1 
  per 
  cent, 
  to 
  14 
  per 
  cent, 
  in 
  the 
  crop 
  

   and 
  no 
  further 
  treatment 
  was 
  given 
  to 
  the 
  crop 
  thereafter 
  for 
  this 
  kind 
  

   of 
  borer. 
  In 
  the 
  year 
  1913, 
  about 
  17 
  acres 
  of 
  ji'.ar 
  were 
  similarly 
  

   treated 
  and 
  the 
  cost 
  of 
  such 
  a 
  treatment 
  came 
  to 
  about 
  0-3-9 
  per 
  acre. 
  

   In 
  the 
  year 
  1912, 
  the 
  attack 
  of 
  Chilo 
  borers 
  was 
  very 
  severe 
  and 
  the 
  

   removal 
  of 
  affected 
  plants 
  with 
  dead-hearts 
  was 
  not 
  rigidly 
  followed 
  

   in 
  the 
  beginning. 
  So 
  the 
  pest 
  ranged 
  from 
  20 
  per 
  cent, 
  to 
  60 
  per 
  cent. 
  

   in 
  some 
  plots, 
  on 
  account 
  of 
  which 
  several 
  plots 
  were 
  grubbed 
  up 
  and 
  

   resown. 
  A 
  plot 
  of 
  three 
  acres 
  in 
  which 
  the 
  plants 
  were 
  attacked 
  to 
  

   an 
  extent 
  of 
  60 
  per 
  cent, 
  was 
  given 
  the 
  following 
  treatment 
  : 
  

  

  All 
  affected 
  shoots 
  with 
  dead-hearts 
  were 
  cut 
  back 
  to 
  the 
  ground 
  

   level. 
  In 
  spite 
  of 
  that 
  the 
  caterpillars 
  in 
  a 
  good 
  many 
  cases 
  were 
  found 
  

   ^ 
  in 
  the 
  portion 
  of 
  the 
  stump 
  remaining 
  in 
  the 
  ground 
  which 
  were 
  also 
  

   being 
  picked 
  and 
  killed 
  by 
  means 
  of 
  a 
  needle 
  or 
  thorn. 
  The 
  cost 
  of 
  

   such 
  a 
  treatment 
  came 
  to 
  about 
  Rs. 
  1-2-0 
  per 
  acre. 
  Later 
  on 
  the 
  

   treated 
  crop 
  gave 
  out 
  very 
  vigorous 
  healthy 
  shoots 
  and 
  in 
  comparison 
  

   with 
  the 
  resown 
  and 
  untreated 
  plots, 
  it 
  yielded 
  more 
  in 
  seed, 
  kadbi 
  

   and 
  chaff, 
  which 
  will 
  be 
  seen 
  from 
  the 
  figures 
  given 
  below 
  : 
  — 
  

  

  From 
  this 
  it 
  leads 
  us 
  to 
  conclude 
  that 
  though 
  timely 
  treatment 
  

   of 
  the 
  removal 
  of 
  affected 
  plants 
  at 
  the 
  time 
  of 
  thinning 
  was 
  not 
  prac- 
  

   tised, 
  however, 
  it 
  yielded 
  more 
  in 
  comparison 
  with 
  other 
  resown 
  and 
  

   untreated 
  plots 
  by 
  cutting 
  back 
  the 
  affected 
  shoots 
  with 
  dead-hearts 
  

   later 
  on. 
  

  

  2. 
  Tachinid 
  fly 
  parasites 
  also 
  play 
  a 
  very 
  important 
  part 
  in 
  con- 
  

   trolling 
  this 
  borer. 
  In 
  the 
  beginning 
  of 
  the 
  monsoon 
  these 
  flies 
  are 
  

  

  