Abstract

Barnyard grass is acknowledged as the most troublesome weed in rice fields in West Java province of Indonesia due to development of resistance to certain chemical control measures. Therefore, this study was conducted during 2020 at the greenhouse of Faculty of Agriculture, Universitas Padjadjaran, Indonesia aimed to confirm and classify the presence of herbicide-resistant of Echinochloa crus-galli toward metsulfuron-methyl and penoxsulam. The resistance level test of E. crus-galli was performed using the Whole Plant Pot Test method laid out under Split Plot Design with 3 replications. The main plot comprised of metsulfuron-methyl herbicide: 0, 1, 2, 4, 8, 16 and 32 g a.i./ha, whereas for the dose of penoxsulam herbicide was 0, 2.5, 5, 10, 20, 40 and 80 g a.i./ha. The subplot was the origin of weed: exposed and not exposed to herbicides. The results showed that E. crus-galli from East Karawang was included in to low level of resistance to metsulfuron-methyl with a resistance ratio of 5.88. This study has affirmed resistance to metsulfuron-methyl in E. crus-galli for the first time. In contrast, no resistance was observed in E. crus-galli samples to penoxsulam.