Department of Agricultural Engineering, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil.
Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America.
PLoS One. 2018 Oct 26;13(10):e0206378. doi: 10.1371/journal.pone.0206378. eCollection 2018.
This study aimed to evaluate 1) the influence of gibberellic acid (GA3) in the development of Tifton 85 bermudagrass grown in constructed wetland systems (CWs) and 2) the plant's capacity to remove nutrients and sodium from synthetic municipal wastewater (SMW). The experiment was carried out in Viçosa, Minas Gerais, Brazil, and consisted of foliar applications of GA3 set in randomized blocks design, with four replicates and 6 treatments as following: NC (control with plants); 0 μM GA3; N1: 5 μM GA3; N2: 25 μM GA3; N3: 50 and N4: 100 μM GA3 per CWs, NC* (control with no plants): 0 μM GA3. The study was conducted over two crop cycles in the spring 2016. The parameters used to evaluate the performance of the Tifton 85 bermudagrass were its plant height, productivity, chlorophyll measurement, number of internodes, nutrients and Na removals. Chemical analyses of the effluents were conducted. In response to the application of GA3, the increase in height of Tifton 85 bermudagrass in the first crop cycle was higher than the increase in height in the second crop cycle. The decrease in plant growth in response to GA3 in the second crop cycle may be linked to the age of the plant tissue and climatic conditions. The greater growth of the plants cultivated in the CWs allows a more efficient removal of pollutants, using simple management and low cost. The results suggest that applying 50 μM of GA3 to the development of Tifton 85 bermudagrass provides higher dry matter yield and removal of nitrogen, phosphorus, and sodium for the first crop cycle in CWs. However, in the second crop cycle, the application of GA3 had no effect on dry matter production and nutrient removal by Tifton 85 bermudagrass in CWs.
本研究旨在评估 1）赤霉素（GA3）对生长在人工湿地系统（CWs）中的堤丰 85 百慕大草的发育的影响，以及 2）该植物从合成城市废水中去除营养物和钠的能力。该实验在巴西米纳斯吉拉斯州维索萨进行，采用随机区组设计进行叶面喷施 GA3，设 4 个重复和 6 个处理，如下：NC（对照，有植物）；0 μM GA3；N1：5 μM GA3；N2：25 μM GA3；N3：50 和 N4：100 μM GA3/每个 CWs，NC*（对照，无植物）：0 μM GA3。该研究在 2016 年春季进行了两个作物周期。用于评估堤丰 85 百慕大草性能的参数包括其株高、生产力、叶绿素测量、节间数、养分和 Na 去除率。对废水进行了化学分析。对 GA3 的应用做出响应，堤丰 85 百慕大草在第一个作物周期中的高度增加高于第二个作物周期中的高度增加。在第二个作物周期中，植物对 GA3 的生长反应下降可能与植物组织的年龄和气候条件有关。在 CWs 中种植的植物生长得更大，从而可以更有效地去除污染物，采用简单的管理和低成本。结果表明，在 CWs 中应用 50 μM 的 GA3 可促进堤丰 85 百慕大草的发育，在第一个作物周期中提供更高的干物质产量和氮、磷和钠的去除率。然而，在第二个作物周期中，GA3 的应用对 CWs 中堤丰 85 百慕大草的干物质生产和养分去除没有影响。
