INTEGRATED WEED MANAGEMENT IN GROUNDNUT BASED INTERCROPPING SYSTEM- A REVIEW

Minimizing the crop-weed competition particularly at early stage of groundnut usually encounters
with diverse weed flora, the yield could improved upon by about 20-30%. Reduction of pod yield
owing to competition with weed depends on the duration of the crop weed competition in general
and the stages of crop growth in particular. The yield losses are more pronounced in rain fed crop.
When the groundnut fields are kept weed free for a period of at least first 6 weeks there is no
significant reduction in pod yield. On the other hand, when groundnut competes with weeds at 4 -
8 weeks the reduction in pod yield is substantial. Effectiveness of weed control is largely dependent
on the weed species prevalent, its life cycle and method of propagation. Since mechanical / cultural
method alone does not ensure weed free condition, the use of herbicides in combination with
cultural methods should be adopted. In areas where agricultural labourer is scarce and costly, herbicides
may be used as pre and post emergence application to control weeds. Several studies have shown
that the productivity of groundnut is reduced considerably when weed competition occurs during
the early stage of the crop. Several workers have reported different critical periods ranging from 30
to 60 DAS revealed that critical period of weed competition was between 2 to 8 weeks after sowing.
In general, weed competition in groundnut is more severe for the first 6 weeks from sowing. Several methods have been employed to check the growth of weeds and to improve the crop stand and productivity. From the traditional method of hand weeding and hoeing, modernized methods of
weed management is the need of the day through the introduction of herbicides to meet labor
shortage to effect early weed control and reduce the cost of weeding. However, no single method
has been found to be quite effective in reducing the weed intensity and hence an integrated approachis essential. The integrated method of weed control is found to be more suitable for the managementof a broad spectrum of weeds.