A preliminary study of 'Tidy Field Technology' to assess growth, development and weed control in direct-seeded rice

Direct-seeded rice (DSR) is an important method to achieve simplified and mechanized rice planting in economical manner. However, proper weed management is a major limiting factor in the development of DSR. 'Tidy field technology' (TFT) is a new non-transgenic herbicide-resistant (HR) cropping technology, which refers to 'herbicide-resistant crops combined with broad-spectrum herbicide', and has been widely confirmed to effectively suppress weed populations in agriculture. However, it is rarely applied in DSR production in China. Therefore, field experiments were conducted to determine the effects of TFT on rice growth and weed control in 2019 and 2020. In this study, two rice varieties, Huanghuazhan-HHZ (Vc) and herbicide-resistant HHZ (Vr) were adopted and practiced with broad-spectrum herbicide management (Hb) and conventional herbicide management (Hc). An equal amount of water was sprayed on Vc as a control (CK). Thus, there were five treatments: VrHb, VrHc, VcHb, VcHc and CK. The grain yields of VrHb was increased by 8.4% and 160.3% in 2019, and 16.0% and 226.6% in 2020 compared with VrHc and CK, respectively. Furthermore, there were no significant differences in grain yield between VrHb and VcHc, but the total economic benefit of VrHb was significantly higher than that of VcHc. In addition, the tiller number, leaf area index (LAI), and aboveground total dry weight (TDW) of VrHb were significantly higher than VrHc, VcHc and CK. In contrast, weed species and density under VrHb were significantly lower than those under VrHc, VcHc and CK. Overall, TFT (VrHb) could replace conventional weed management for DSR due to a better weed control effect and higher economic benefit with similar or even higher grain yield. However, it is necessary to explore the effects of TFT residue on soil physical and chemical properties, microorganisms and the growth of subsequent crops in the near future.