Indaziflam Effect on Bermudagrass (Cynodon dactylon L. Pers.) Shoot Growth and Root Initiation as Influenced by Soil Texture and Organic Matter

Abstract

Indaziflam is an alkylazine herbicide used for preemergence control of annual weeds in warm‐season turfgrass. Growth chamber studies were conducted to determine the effect of indaziflam rate on bermudagrass (Cynodon dactylon L. Pers.) shoot and root initiation as influenced by soil texture and organic matter (OM). Bermudagrass plants propagated from stolons were planted in five different growing media, including pure sand (100% sand), sand (92% sand, 6% clay) with or without OM (2%), and loamy sand (82% sand, 12% clay) with or without OM (2%). Indaziflam at rates of 48 or 16 g ha−1 followed by drenches of 2.5 cm of water were applied to the bermudagrass plants after maximal root length reached 30 cm. Bermudagrass growing in pure sand, regardless of indaziflam rate, showed the most injury, with root and shoot biomass reduced to <10 and <32%, respectively, compared with the nonherbicide‐treated control 38 d after treatment (DAT). Increase in clay content and addition of OM at 16 g ha−1 indaziflam significantly improved root biomass to ≥40% at 38 DAT. Despite inhibitions to root growth, aboveground tissues of plants growing in sand and loamy sand with OM showed minimal or no changes in turf color and coverage at 16 g ha−1 indaziflam. Results of this study indicate that small amounts of clay and OM in sandy soil aid in reducing bermudagrass phytotoxicity risk of 16 g ha−1 indaziflam.

Effect of Indaziflam Application and Soil Manipulations on Pecan Evapotranspiration and Gas Exchange Parameters

“…This small difference could partially explain the absence of phytotoxicity effects in young pecan trees exposed even to an application rate two times greater than the recommended application field rate of indaziflam. Schneider et al (2015) reported increased sorption of indaziflam with increasing organic matter content after evaluating the phytotoxicity of indaziflam on bermudagrass.…”

Native seeds incorporated into activated carbon pods applied concurrently with indaziflam: a new strategy for restoring annual‐invaded communities?

“…Additionally, field experiments evaluating long‐term survival of seedlings established within HPPs are crucial. Soil organic matter content, soil volumetric water content, soil texture, indaziflam application rate, and rooting depth of plants all affect the amount of injury caused by indaziflam to postgerminative establishment of grass species (Gomez de Barreda et al ; Jones et al ; Schneider et al ; Jeffries & Gannon ). The long‐term effects of HPPs have not been studied and it is unknown if they will limit indaziflam injury beyond early seedling growth.…”

Effect of Organic Matter on the Behavior and Control Effectiveness of Herbicides in Soil

“…The factors affecting the sorption processes determine the other routes to be taken by the herbicides in the soil. The bioavailability for weed absorption can be altered with the addition of OM in the soil, and there may be a reduction in the risk of phytotoxicity of the herbicide (Szmigielski et al, 2009;Gannon et al, 2014;Schneider et al, 2015). For acidic, polar, and low pK a herbicides, this influence of OM on the behavior of the product in the environment may be lower, since they have low affinity of sorption with the SOM (Stevenson, 1972).…”