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Genomics and Applied Biology 2015, Vol. 6, No. 3, 1-14
http://gab.biopublisher.ca
6
control efficiency followed by two hand weeding with
87 per cent WCE and one weeding followed by
earthing up treatment with maximum (93%) WCE at
45 DAS indicating suppression of first flush of weeds
successfully in maize.
Kolage
et al
. (2004) reported that among the
herbicides, pre-emergence spraying of atrazine at 1.0
kg ha
-1
reduced the weed intensity substantially and
recorded lower weed index and maximum weed control
efficiency as compared to other herbicides used in maize.
Rao
et al
. (2009) investigated that pre-emergence
application of atrazine 1.5 kg ha
-1
followed by hand
weeding at 30 DAS recorded lower weed dry weight
at 60 DAS and harvest in maize.
Oxyfluorfen
Singh (1988) reported that oxyfluorfen at 0.20 kg per ha
as pre-emergence reduced the weed population by 85
per cent over weedy check and increase in herbicide
dose caused burning effect on emerging sprouts in
potato. Singh
et al
. (1990) concluded that
per-emergence application of oxyfluorfen at 0.25 kg
ha
-1
gave maximum yield and higher weed control
efficiency in onion. Singh
et al
. (1992) reported the
maximum bulb yield and higher weed control
efficiency with oxyfluorfen @ 0.25 kg ha
-1
when
applied 3 days before transplanting in onion. Porwal
(1995) suggested that pre-emergence application of
oxyflourfen (1.0 kg ha
-1
), oxadiazon (1.0 kg ha
-1
) and
pendimethalin (1.25 kg ha
-1
) supplemented with one
hand weeding at 40 days after sowing showed 90
per cent weed control efficiency and reduced dry
weed biomass to as low as 49.0-50.4 q ha
-1
in garlic.
Yadav
et al
. (2000) reported that pre emergence
application of oxyfluorfen at 0.15 kg ha
-1
recorded
higher net income over other treatments in soybean.
Kolhe (2001) indicated that dry matter of weeds was
significantly reduced due to application of
pendimethalin, metalachlor, oxyfluorfen either alone
or in combination with hand weeding at 35 DAP
compared to weedy check in onion.
According to Ranpise and Patil (2001), pre-emergence
application of oxyfluorfen at 0.40 kg ha
-1
produced
maximum yield (242 q ha
-1
) followed by oxyfluorfen
at 0.20 kg ha
-1
(233 q ha
-1
) as compared to all other
treatments in onion. The lower yield was under
control plot (50 q ha
-1
) due to maximum weed
intensity.
Pre-emergence application of oxyfluorfen at 0.125 kg
ha
-1
and pendimethalin at 0.5 kg ha
-1
can be applied for
better weed control and higher seedling production in
onion as reported by (Sharma
et al
.
,
2009). Ratnam
et
al
. (2012) recorded that pre-emergence application of
oxyfluorfen @ 0.25 kg ha
-1
followed by
post-emergence application of quizalofop ethyl @
0.05 kg ha
-1
followed by weeding at 60 and 90 DAP
recorded higher fresh rhizome yield in turmeric.
According to Sathya Priya
et al
. (2013), pre-emergence
application of oxyfluorfen (23.5per cent EC) at 200 g
ha
-1
recorded lesser weed density and dry weight in
onion.
Oxadiargyl
Mirza Hasanuzzaman
et al
. (2009) reported that
pre-emergence application of oxadiargyl at 190 ml
ha
-1
+ 1 hand weeding at 25 DAT recorded lesser weed
density, dry weight and higher weed control efficiency
and grain yield in rice. Pre-emergence application of
oxadiargyl at 75 g ha
-1
fb bispyribac-sodium 30 g ha
-1
at 20 DAT was at par with HW twice at 20 and 40 DAT
in achieving higher grain yield in transplanted rice
(Deepthi Kiran and Subramanyam, 2010).
According to Naseeruddin
et al
. (2014),
pre-emergence application of oxadiargyl 75 g ha
-1
followed by post-emergence application of
azimsulfuron 30 g ha
-1
resulted in broad spectrum
weed control coupled with the highest grain yield
drum seeded rice (5.75 t ha
-1
).
Post - Emergence Herbicides
Pre-emergence or pre plant incorporated herbicides
have a narrow spectrum of weed control. Further if
farmers skip the application of these herbicides due to
one (or) the other reason, there is a need of alternative
post-emergence herbicides for managing weeds. Post
emergence herbicides have broad spectrum of activity.
Metsulfuron methyl
Karmakar
et al
. (1994) reported that toxic effects of this
herbicide on dicots
viz
.
,
Digera arvensis, Euphorbia
