Stimulation of Stem Growth in Vegetative Tillers of Poa Pratensis L. By Ethephon: Elongation of Nodes

Ethylene-Induced Chlorosis in the Pathogenesis of Bipolaris sorokiniana Leaf Spot of Poa pratensis

“…This observation suggests that ethylene functions late in pathogenesis of this host-pathogen interaction and that other physiological phenomena ofthe interaction may be necessary to predispose the infected tissue to ethylene damage. Predisposition of host tissue to ethylene damage is suspected because applications of Ethephon to healthy P. pratensis may cause several changes in growth, but it does not induce chlorosis (25,26 …”

Changes in Endogenous Gibberellins and the Metabolism of [3H]GA4 after Geostimulation in Shoots of the Oat Plant (Avena sativa)

“…When Avena shoots are geostimulated, one, and usually two node-pulvini respond by negative geotropic curvature over a period of 20 min to 48 h (6,7). This growth in the nodepulvinus which results in negative geotropic curvative can be enhanced by, and is very sensitive to, auxin application in A vena (13), and in Poa pratensis to Ethephon, and especially Ethephon plus GA3, but not to GA3 alone (25). In A vena, a festucoid grass, the leaf sheath pulvinus (termed node-pulvinus hereafter) is a significant source of GAs, as are elongating internodes and inflorescences (15).…”

Effects of ethephon on growth and morphology of perennial grasses

“…When gibberellin was applied simultaneously with ethephon, the response was similar to plants treated only with ethephon, that is, elongated internodes and a reduction in leaf blade length caused by decreased cell number. Therefore, gibberellin was ineffective in promoting leaf blade cell division (van Andel, 1973;Verkerke and van Andel, 1978). Perhaps ethephon also may moderate the concentration or activity of other phytohormones, such as cytokinin.…”

“…Similar responses to ethephon have been noted in some grass species. Much like in aquatic plants, ethephon promotes the formation of elongated internodes in Kentucky bluegrass (Poa pratensis L.) (Christians, 1985;Diesburg and Christians, 1989;Diesburg and Christians, 1993;Poovaiah and Leopold, 1973;van Andel, 1973; van Andel and Verkerke, 1978;Verkerke and van Andel, 1978). This response is curious given that Kentucky bluegrass plants generally produce a compact stack of nonelongated internodes.…”

“…In addition to increased internode elongation, ethephon also causes a significant reduction in Kentucky bluegrass leaf blade length (Christians, 1985;Diesburg and Christians, 1989;Diesburg and Christians, 1993;Poovaiah and Leopold, 1973;van Andel, 1973;van Andel and Verkerke, 1978;Verkerke and van Andel, 1978).…”