Efficacy
evaluation of selected herbicides on weed control and productivity evaluation
of Bt cotton in Punjab
Kulvir Singh* and
Pankaj Rathore
Punjab
Agricultural University, Regional Research Station, Faridkot-151 203, India
*Corresponding
Author?s E-mail: kulvir@pau.edu
|
Publication
Data
Paper received:
05 February 2014
Revised received:
07 July 2014
Accepted:
28 August 2014
|
Abstract
Field
experiments were conducted during Kharif 2012 and 2013 to evaluate the
efficacy of different herbicides for weed management in cotton. Highest seed
cotton yield (3537.3 kg ha-1) was recorded in weed free plots
followed by pendimethalin @1.0kg a.i ha-1 as
Pre.em.+quizalofopethyl @50g a.i ha-1 post-em at 2-4 weed leaf
stage + one hoeing (3318.9 kg ha-1) owing to improved number of
bolls per plant and boll weight. Statistically least yield was recorded under
weedy check (1435.4 kg ha-1). Application of pyrithiobac sodium
could not express any visible toxic effect on crop indicating its selectivity
for cotton, although none of the tested new chemicals i.e.,
pyrithiobac sodium@ 62.5g a.i ha-1 and quizalofopethyl @50g a.i ha-1
when applied alone could not outperform the existing recommended chemicals
for weed management. Yield losses to the extent of 6.2-59.4% were recorded
due to weed competition. Weed control efficiency (WCE) was highest under weed
free check (86.8%) followed by pendimethalin @1.0kg a.i ha-1 as
Pre. em.+quizalofopethyl @50g a.i ha-1, at 2-4 weed leaf stage +
one hoeing (73.7%) , whereas minimum values were for weedy check (24.7%).
Though net returns (`94660 ha-1) were highest for weed free check but higher
B:C ratio (2:11) was observed for pendimethalin @1.0kg a.i ha-1 as
Pre em.+quizalofopethyl @50g a.i ha-1 post-em at 2-4 weed leaf
stage+one hoeing . Therefore, for reasons such as labor shortage besides their
timely availability, using? these herbicides in combination with cultural
practices could be the practical solution for economically efficient and
effective weed management. ?
Key
words
Herbicide,
Seed cotton yield, Sympods, Weed control efficiency
|
Copyright
? 2015 Triveni Enterprises. All rights reserved. No part of the Journal can
be reproduced in any form without prior permission. Responsibility regarding
the authenticity of the data, and the acceptability of the conclusions
enforced or derived, rest completely with the author(s).
|