Use of Prohexadione Calcium on Grass Species Development

ABSTRACT: This study has aimed to evaluate the effect of prohexadione-calcium as a plant growth regulator on growth and quality of Japanese lawn grass, Broadleaf carpet grass and Bermudagrass. The treatments and doses of the prohexadione-calcium tested with two three reapplications were 27.5, 55.0, 110.0, 165.0 and 165.0 g a.i. ha-1, and a control without application of a growth regulator. Visual injury evaluations were performed using a scale of scores and plant height and chipping dry matter were determined. We have evaluated the total thickness of the sod grass, root length and dry matter of this material at the end of the experimental period. The study was arranged in a completely randomized design with four replications. The results were submitted to analysis of variance by F-test and the averages of the treatments were compared by t test at 5% probability. The prohexadione-calcium plant growth regulator was visually selective and reduced shoot growth of the three species of grass and can thus be used in the management of lawns in gardens and sports areas. As for the production of sod grass, the prohexadione-calcium can be recommended for Japanese lawn grass and Broadleaf sod grass, especially doses 165.0+165.0 and 55.0+55.0+55.0 respectively, because they have provided a better quality sod grass. For Bermudagrass, the effect of the treatments was harmful for the quality of sod grass and is not recommended for production purposes.

摘要：本研究旨在评估调环酸钙（prohexadione-calcium）作为植物生长调节剂（plant growth regulator）对日本结缕草、宽叶地毯草及狗牙根的生长与品质的影响。试验设置采用两次、三次喷施方式的调环酸钙处理，施用量分别为27.5、55.0、110.0、165.0及165.0 g有效成分/公顷，同时设置不施用生长调节剂的空白对照组。试验采用评分法开展外观受害程度评价，并测定植株株高与剪草干物质量；于试验结束时测定草皮总厚度、根系长度及根系干物质量。本试验采用完全随机设计（completely randomized design），设置4次重复。试验数据采用F检验（F-test）进行方差分析，并在5%显著水平下通过t检验（t-test）对处理组均值进行比较。结果表明，调环酸钙植物生长调节剂具有选择性，可抑制3种供试草坪草的地上部生长，因此可应用于园林及运动场地的草坪管理。就草皮生产而言，调环酸钙可推荐用于日本结缕草与宽叶地毯草，分别以165.0+165.0 g有效成分/公顷的两次喷施剂量与55.0+55.0+55.0 g有效成分/公顷的三次喷施剂量为佳，该处理可获得品质更优的草皮。而对于狗牙根，各处理对其草皮品质均存在不利影响，因此不推荐用于其草皮生产。