# Sustainable Weed Management: The Effects of Applying Pre- and Post-Emergence Herbicides to Medicago ruthenica

## TL;DR

This study finds effective herbicides to control weeds in Medicago ruthenica, improving crop safety and sustainability in arid regions.

## Contribution

The study introduces viable pre- and post-emergence herbicide strategies for Medicago ruthenica, previously unexplored.

## Key findings

- Imazethapyr and flumetsulam are effective pre-emergence herbicides with no harm to the crop or soil microbes.
- Imazethapyr + haloxyfop-P and 2,4-DB + haloxyfop-P are effective post-emergence herbicides for weed control.
- These herbicides control weeds like A. retroflexus and grasses while maintaining crop safety and yield.

## Abstract

Medicago ruthenica is a forage legume crop that is widely used as fodder and for ecological restoration in arid and semi-arid areas in Northcentral Asia. During the seedling stage, weeds challenge the growth and development of M. ruthenica, especially in fields sown for seed production. However, strategies to effectively control weeds in crops of M. ruthenica using herbicides have not been investigated. We evaluate the efficacy of different herbicides that control pre- and post-emergence of weeds in M. ruthenica. The results indicated that the most effective pre-emergence herbicides, imazethapyr (1530 mL ha−1) and flumetsulam (120 mL ha−1), resulted in crop safety and soil microbial community equivalent to a weed-free check. The most effective post-emergence herbicides are imazethapyr + haloxyfop-P (1800 + 600 mL ha−1) and 2,4-DB + haloxyfop-P (2250 + 600 mL ha−1). These herbicide treatments demonstrate effective control of most weeds (A. retroflexus, C. album, and grasses) while ensuring crop safety. Application of these herbicides to control weeds in M. ruthenica prior to or after their emergence represents a viable strategy for their control and also improve agricultural viability and crop yield and quality. Our research contributes to sustainable agriculture and ecological restoration in arid regions.