HERBICIDES in Asian rice - IRRI books - International Rice ...

Surveys of information recall and impact indicate that the remarkable reduction
of Echinochloa population was attributable to the following factors (Khor and Ramli
1990):
• General improvement in water management. More farmers (89.4%) were aware
of the irrigation schedule issued by MADA, and approximately 62.6% were
capable of adhering to the schedule. Before the campaign, only 63.9% of the
farmers were aware of the schedule and 49.8% could adhere to it (Fig. 5).
• Appropriate adoption of cultural practices. Post-campaign evaluation indicated
that more farmers (42.4%) dry-cultivated their land twice, as recommended,
compared with only 24.9% prior to the campaign. The number of farmers who
leveled their fields also increased remarkably, from 15 to 94%. The campaign
also created an awareness among the farmers of the importance of using pure
seeds. Approximately 31.9% of the farmers obtained their seeds from authorized
sources after the campaign, compared with 24.1 % before (Fig. 6).
• Appropriate herbicide application. Post-campaign data indicated an increase
in the use of propanil, from 4.8% of the farmers to 16.7%. Similar increased
use was observed for the propanil + molinate mixture, from 5.3 to 19.3%
(Fig. 7). Farmers’ knowledge about correct timing of herbicide application
increased from 11.1 to 40% for propanil, and from 30 to 63.6% for propanil +
molinate mixture. Knowledge of correct herbicide dosage increased from 9 to
45.4% for propanil and from 9 to 54.1 % for propanil + molinate.
On the whole, the systematically planned, multimedia strategic campaign was
successful in controlling Echinochloa species, the most serious weed problem in the
Muda area. Average rice yields increased 27%, from 3.1 t ha -1 in the first 1988 season
to 3.95 t ha -1 in the first 1989 season. Continuing implementation of the 1990-94
campaign has had remarkable results. Dry-seeded, first-season rice yields have in-
5. Water management in the Muda area before and
after IWM campaign (Khor and Ramli 1990).
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