Biostimulator Enhancement of Kentucky Bluegrass Sod

Abstract

<jats:p>This study was conducted to determine if foliar-applied biostimulators could enhance harvestability and transplanting of Kentucky <jats:italic>bluegrass (Poa pratensis</jats:italic> L.) sod. The systemic triazole fungicides propiconazole at 42 mg·m<jats:sup>-2</jats:sup> and triadimefon at 150 mg·m-<jats:sup>2</jats:sup> enhanced post-transplant rooting and sod strength of bluegrass. Propiconazole had the best sod enhancement effect, increasing sod tensile strength 23% and increasing transplant root lift strength 64% across three experiments. The synthetic cytokinin benzyladenine (BA) at 6 mg·m<jats:sup>-2</jats:sup> and seaweed extract (SWE, a freeze-dried extract of the seaweed <jats:italic>Ascophyllum nodosum)</jats:italic> at 0.3 ml product/m <jats:sup>2</jats:sup> had little effect. The response to triadimefon was intermediate. Foliar applications of chelated Fe phosphate citrate at 112 mg·m<jats:sup>-2</jats:sup> did not enhance sod strength or rooting of Kentucky bluegrass when applied either alone or in combination with the biostimulator materials. Chemical names used: l-(2-(2,4 -dichlorophenyl)-4-propyl-l,3-dioxo1an-2-ylmethyl)-lH-l,2,4-triazole(propiconazole);1-(4-chlorophenoxy)-3,3-dimethyl-lH-(l,2,4-triazo1-l-yl)-butanone (triadimefon);6-benzylaminopurine (BA, benzyladenine).</jats:p>

Plant Growth Regulators Can Enhance the Recovery of Kentucky Bluegrass Sod from Heat Injury

“…A piece of sod (0.3 by 0.3 m) was cut from the center of the roll and a 0.3‐ by 0.3‐m sheet of expanded metal was inserted under this piece of sod for subsequent rooting determination. The metal rooting sheet has uniformly distributed diamond‐shaped openings (3.8 cm long by 1.6 cm wide at middle) for roots to grow past (Goatley and Schmidt, 1991; Schmidt et al, 1986). There was a distance of 30 cm between each piece of sod.…”

“…Three weeks after transplanting, turfgrass injury was rated based on a visual scale of 1 to 9, with 9 indicating the most injury. Six weeks after transplanting, transplant rooting was determined by measuring the energy required to vertically lift the expanded sheet of metal through which the sod roots had grown (Goatley and Schmidt, 1991; King and Beard, 1969). Briefly, hooks were attached to the corners of the steel squares and the amount of force required to lift the roots free from the soil was recorded with a 100‐kg hand‐held push/pull scale.…”

“…Selected PGRs have been used to enhance turfgrass growth and tolerance to environmental stresses, including UV radiation and high temperature (Schmidt and Zhang, 2001). Goatley and Schmidt (1991) reported application of benzyladenine and PPC increased rooting of KBG sod as much as 23%. Heckman et al (2001) noted that trinexapac‐ethyl reduced the internal temperature of KBG sod stacks after 48 h of storage.…”

“…Transplant rooting is an important parameter for survival and successful establishment of sod (Giese et al, 1997; Goatley and Schmidt, 1991). Selected PGRs have been used to enhance turfgrass growth and tolerance to environmental stresses, including UV radiation and high temperature (Schmidt and Zhang, 2001).…”

“…These materials have been shown to enhance PE and root and shoot growth of KBG and creeping bentgrass ( Agrostis palustris Huds. ; Goatley and Schmidt, 1990, 1991; Zhang and Schmidt, 2000a). However, there are few studies concerning the influence of these PGRs on PE and transplant sod survival and rooting.…”