Book of Extended summaries ISDA

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges &
Opportunities during 22-24, December 2022 at ICAR-CRIDA, Hyderabad
integration of cultural and chemical methods is required for effective management of weeds
especially sedges in wet DSR. Conservation agriculture is a machine, herbicide and
management driven agriculture with integrated weed management involving chemical and nonchemical
methods for its success in the long-run (Sharma et al., 2014). In addressing weed
control challenges, studies have shown that minimum and no-tillage reduce the weed
population and also provide other ecosystem services like sustainable land management,
environmental protection and climate change adaptation and mitigation (Sims et al., 2018).
Unless weed management is sustainably addressed in conservation agriculture, particularly in
the initial years, weed pressure, weed resistance and inherent crop yield losses may deter
farmers from adopting conservation practices. With this background, this study was conducted
to evaluate integrated weed management options for the effective management of weeds in
rice, especially sedges which have become difficult to control in DSR.
Methodology
The experiment was conducted at Rice Research Station, Moncompu, Kerala Agricultural
University, during the rabi 2021 -22 and kharif 2022, in split plot design with three main plots
and five sub plots. The main plots were different land preparation practices viz., zero tillage
followed by stale seed bed technique (SSB) and herbicide application to destroy the germinated
weeds, tillage followed by SSB technique and herbicide application to destroy the germinated
weeds, and tillage followed by SSB technique and destroying the germinated weeds again by
tillage (repeated tillage). In the sub plots, various herbicides were evaluated for its effectiveness
under different tillage conditions, viz., pre-emergence application of Pyrazosulfuron @ 0.02 kg
ai/ha followed by post-emergence application of Penoxulam + Cyhalofop butyl @ 0.135 kg
ai/ha, post-emergence application of Fenoxaprop ethyl @ 0.06 kg ai/ha followed by
Metsulfuron methyl + Chlorimuron ethyl @ 0.004 kg ai/ha, post-emergence application of
Fenoxaprop ethyl @ 0.06 kg ai/ha followed by 2,4-D @ 1.00 kg ai/ha, two hand weedings and
weedy check. The most popular rice variety of the region, Uma (MO 16) was used in the
experiment. Observations on plant height, plant population, tiller count, total dry matter
production, weed count and weed dry weight was recorded at 15, 30, 60, 80 and 110 DAS of
the crop. Grain and straw yield were also recorded at harvest.
Results
The results revealed that at 15 DAS, main plots, where land preparation was done by zero
tillage followed by SSB with application of broad-spectrum herbicide to destroy the germinated
weeds had significantly lower weed population followed by plots where land preparation was
done by tillage followed by SSB with application of broad-spectrum herbicide. Significantly
higher weed population was noticed in the treatment with tillage followed by SSB technique
and destroying the germinated weeds by tillage (repeated tillage). At 30 DAS, plots where land
363 | Page Managing genetic resources for enhanced stress tolerance