Herbicide sequence

Phalaris minor

Post-emergence

Wheat

Littleseed canary grass (Phalaris minor) is the ubiquitous and pernicious grass weed of wheat in rice-wheat cropping system in north-western Indo- Gangetic plains of India. A field experiment was conducted during Rabi 2014-15 and 2015-16 in a farmers field infested with P. minor having history of poor control with acetyl-CoA-carboxylase inhibitors in village Nangla, district Fatehabad, Haryana, India with an objective to compare pre-emergence only, post-emergence only and pre-emergence followed by post-emergence herbicide treatments for control of P. minor in wheat. The sequential application of pre-emergence pendimethalin 1.5 kg/ha fb post-emergence pinoxaden + metsulfuron 64 g/ha and pre-emergence pendimethalin 1.5 kg/ha fb post-emergence mesosulfuron + iodosulfuron 14.4 g/ha provided 88-93% control of P. minor compared to alone pre- and post-emergence herbicide treatments. Grain yield of wheat increased significantly by 69-78% with pre-emergence pendimethalin 1.5 kg/ha fb post-emergence pinoxaden + metsulfuron 64 g/ha or pre-emergence pendimethalin 1.5 kg/ha fb post-emergence mesosulfuron + iodosulfuron 14.4      g/ha due to significant increase in yield attributes. Alone pre- or post-emergence herbicides provided ineffective control of P. minor (44-66%) and recorded lower grain yield. It was concluded that herbicide sequences having both pre- and post-emergence herbicides would be better option as compared to their alone applications in order to manage resistant populations of P. minor in wheat.