Weed management is an arduous undertaking in crop production. Integrated weed management, inclusive of the application of bioherbicides, is an emerging weed control strategy toward sustainable agriculture. In general, bioherbicides are derived either from plants containing phytotoxic allelochemicals or certain disease-carrying microbes that can suppress weed populations. While bioherbicides have exhibited great promise in deterring weed seed germination and growth, only a few in vitro studies have been conducted on the physiological responses they evoke in weeds. This review discusses bioherbicide products that are currently available on the market, bioherbicide impact on weed physiology, and potential factors influencing bioherbicide efficacy. A new promising bioherbicide product is introduced at the end of this paper. When absorbed, phytotoxic plant extracts or metabolites disrupt cell membrane integrity and important biochemical processes in weeds. The phytotoxic impact on weed growth is reflected in low levels of root cell division, nutrient absorption, and growth hormone and pigment synthesis, as well as in the development of reactive oxygen species (ROS), stress-related hormones, and abnormal antioxidant activity. The inconsistency of bioherbicide efficacy is a primary factor restricting their widespread use, which is influenced by factors such as bioactive compound content, weed control spectrum, formulation, and application method.

Plant-based bioherbicides could be an effective alternative to current chemical herbicides for sustainable agriculture. Therefore, this research evaluated the weed control efficacy and crop-weed selectivity of the new plant-derived bioherbicide WeedLock compared to commercial herbicides in glasshouse and field conditions. In the glasshouse, the herbicides applied were WeedLock (672.75, 1345.50, 2691.00 L ha⁻¹), glyphosate isopropyl-amine, and glufosinate-ammonium (1, 2, 4 L ha⁻¹), over the untreated (control) on six weeds and four crops. In the field trial, typical weeds were allowed to grow at a uniform density across plots (2.5 × 2.5 m), and WeedLock (1345.50, 2691.00 L ha⁻¹), glyphosate isopropyl-amine, and glufosinate-ammonium (2, 4 L ha⁻¹) were applied along with untreated plot (control). A randomized complete block design was set with four replications for glasshouse and field experiments. WeedLock at 1345.50 L ha⁻¹ showed efficacy similar to glyphosate isopropyl-amine and glufosinate-ammonium at 2 L ha⁻¹ for Ageratum conyzoides L. in the glasshouse. Applied herbicides killed all tested crops except Zea mays L. at 1345.50 L ha⁻¹ (WeedLock). WeedLock showed more than 50% efficacy at 35 days after spray, while 65% was produced by glyphosate isopropyl-amine and glufosinate-ammonium compared to the untreated plot (control). WeedLock has excellent potential to control weeds in both glasshouse and field conditions and showed a non-selective character.